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2.
RSC Adv ; 14(6): 3731, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38268548

RESUMEN

[This corrects the article DOI: 10.1039/D1RA01258D.].

3.
Viruses ; 16(1)2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38257773

RESUMEN

Rice stripe disease caused by the rice stripe virus (RSV), which infects many Poaceae species in nature, is one of the most devastating plant viruses in rice that causes enormous losses in production. Ailanthone is one of the typical C20 quassinoids synthesized by the secondary metabolism of Ailanthus altissima, which has been proven to be a biologically active natural product with promising prospects and great potential for use as a lead structure for pesticide development. Based on the achievement of the systemic infection and replication of RSV in Nicotiana benthamiana plants and rice protoplasts, the antiviral properties of Ailanthone were investigated by determining its effects on viral-coding RNA gene expression using reverse transcription polymerase chain reaction, and Western blot analysis. Ailanthone exhibited a dose-dependent inhibitory effect on RSV NSvc3 expression in the assay in both virus-infected tobacco plants and rice protoplasts. Further efforts revealed a potent inhibitory effect of Ailanthone on the expression of seven RSV protein-encoding genes, among which NS3, NSvc3, NS4, and NSvc4 are the most affected genes. These facts promoted an extended and greater depth of understanding of the antiviral nature of Ailanthone against plant viruses, in addition to the limited knowledge of its anti-tobacco mosaic virus properties. Moreover, the leaf disc method introduced and developed in the study for the detection of the antiviral activity of Ailanthone facilitates an available and convenient screening method for anti-RSV natural products or synthetic chemicals.


Asunto(s)
Ailanthus , Productos Biológicos , Cuassinas , Tenuivirus , Tenuivirus/genética , Nicotiana , Antivirales/farmacología
4.
Cladistics ; 38(1): 59-82, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35049080

RESUMEN

A new troodontid (LH PV39) recovered from the Upper Cretaceous Wulansuhai Formation, Inner Mongolia, China, is described, highlighting the dorsoventrally compressed sacral centra. The completely fused neurocentral junctions indicate that LH PV39 had reached adulthood at the time of death, but its size is nevertheless 20% smaller than that of the sympatric Philovenator, demonstrating that it is the second small-bodied troodontid recovered from the Wulansuhai Formation. Phylogenetic analyses scoring LH PV39 using different strategies and performed with different algorithms unambiguously recovered it as a troodontid. While the parsimony-based analysis scoring LH PV39 as an independent OTU with all of its available characteristics included recovered it as a basal troodontid, the Bayesian analysis suggests a closer relationship of LH PV39 to Almas and an unnamed troodontid from Ukhaa Tolgod, Mongolia (MPC-D100/1126+D100/3500). Body size analysis confirmed a single trend of gigantism throughout the evolution of troodontids, and suggests that the Late Cretaceous troodontids evolved in two directions: (i) several size-independent characteristics evolved while retaining the small sizes that are typical of the Early Cretaceous relatives, resulting in the Late Cretaceous small-bodied troodontids; and (ii) size-dependent characteristics (e.g., the elongation of the rostrum) evolved accompanying the size increase, resulting in large-bodied derived troodontids. The mosaic features of the Late Cretaceous small-bodied troodontids place them intermediate between their Early Cretaceous basal relatives and the Late Cretaceous large-bodied taxa in a well-resolved phylogeny, which is crucial for understanding the size and morphological evolution of troodontids.


Asunto(s)
Dinosaurios , Animales , Teorema de Bayes , Tamaño Corporal , China , Dinosaurios/anatomía & histología , Filogenia
5.
Org Lett ; 23(21): 8477-8481, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34661414

RESUMEN

Reported herein is a regioselective difluoromethane sulfonylation or triflylation of resorufin derivatives, which allows easy access to 2-difluoromethane sulfonylated or triflylated resorufin derivatives in good yields. The installation of a difluoromethane sulfonyl group significantly increases the solubility of the chromophore and expands its Stokes shift. A difluoromethane sulfonylated resorufin-based fluorogenic probe proved to be able to image enzyme activity in live cells with a stronger fluorescence signal compared with its resorufin counterpart.

6.
RSC Adv ; 11(43): 26791-26799, 2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-35479982

RESUMEN

Silver/silver halide supported on ordered mesoporous ceria particles (Ag/AgCl/CeO2) were rapidly prepared by microwave-assisted soft template method, deposition precipitation method and photoreduction method, using cerium nitrate and silver nitrate as raw materials and block copolymer F127 as a template. The morphology, structure and chemical composition of the catalyst were characterized by XRD, SEM, EDS, TEM, N2 adsorption-desorption and UV-Vis Drs. Catalytic wet peroxide system assisted with visible light photocatalysis (photo-CWPO) was conducted to investigate the performance of organics degradation by Ag/AgCl/CeO2 as a catalyst in acrylonitrile wastewater. The results showed that the Ag/AgCl/CeO2 prepared has an ordered mesoporous structure, Ag and AgCl are formed on the surface of CeO2, with a specific surface area of 302.6-336.2 m2 g-1 and the average pore size is 8.04-8.90 nm. There is a strong absorption in the visible region and a band gap of 2.9 eV. The Ag/AgCl/CeO2 catalyst has higher catalytic performance in the photo-CWPO system than in the CWPO system alone. Ag loading, catalyst and H2O2 dosage, and pH value can affect the COD removal. When the concentration of COD in acrylonitrile wastewater was 500 mg L-1, the amount of catalyst was 200 mg, the amount of H2O2 (30%) was 8 mL, and the reaction time was 60 min, the COD removal reached 90%.

7.
RSC Adv ; 11(26): 15959-15968, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35481213

RESUMEN

Ordered mesoporous Ag/CeO2 catalysts have been successfully synthesized by a microwave assisted soft template method. The morphology, structure and chemical composition of the catalyst were characterized by XRD, N2 adsorption-desorption, SEM, EDS, TEM and XPS. The study of catalytic performance and reaction kinetics of organic matter degradation in acrylonitrile wastewater was performed in a catalytic wet peroxide (CWPO) system. The degradation pathways of organic matter in acrylonitrile wastewater were elucidated by temporal evolution of intermediates and final products detected by GC/MS analysis along with a continuous flow experiment study. The results show that the Ag/CeO2 has an ordered mesoporous structure, the specific surface area is 91.4-118.2 m2 g-1 and the average pore size is 12.63-16.86 nm. 0.4-Ag/CeO2 showed the best catalytic performance, the COD removal rate reached 94.6%, which was 30% higher than that of CeO2. The degradation is in accordance with the second-order reaction kinetics of the Arrhenius empirical model and Langmuir-Hinshelwood kinetic model. However the latter fits better, and the linear correlation coefficient R 2 is more than 0.98, which describes the adsorption catalytic mechanism of Ag/CeO2. According to the analysis by GC/MS, the organic compounds in acrylonitrile wastewater oxidized into intermediate compounds and other small compounds, then are further oxidized into carbon dioxide and water. The catalytic activity of Ag/CeO2 was the result of the combination of Lewis acid-base position of CeO2 and redox cycle of Ce3+/Ce4+.

8.
Molecules ; 25(23)2020 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-33276431

RESUMEN

Phytochemistry investigations on Ailanthus altissima (Mill.) Swingle, a Simaroubaceae plant that is recognized as a traditional herbal medicine, have afforded various natural products, among which C20 quassinoid is the most attractive for their significant and diverse pharmacological and biological activities. Our continuous study has led to the isolation of two novel quassinoid glycosides, named chuglycosides J and K, together with fourteen known lignans from the samara of A. altissima. The new structures were elucidated based on comprehensive spectra data analysis. All of the compounds were evaluated for their anti-tobacco mosaic virus activity, among which chuglycosides J and K exhibited inhibitory effects against the virus multiplication with half maximal inhibitory concentration (IC50) values of 56.21 ± 1.86 and 137.74 ± 3.57 µM, respectively.


Asunto(s)
Ailanthus/química , Antivirales/farmacología , Glicósidos/farmacología , Nicotiana/efectos de los fármacos , Extractos Vegetales/farmacología , Cuassinas/química , Virus del Mosaico del Tabaco/efectos de los fármacos , Lignanos/farmacología , Corteza de la Planta/química , Nicotiana/virología
9.
Bioorg Med Chem ; 28(4): 115301, 2020 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-31953129

RESUMEN

A new non-cytotoxic [(+)-17ß-hydroxystrebloside (1)] and two known cytotoxic [(+)-3'-de-O-methylkamaloside (2) and (+)-strebloside (3)] cardiac glycosides were isolated and identified from the combined flowers, leaves, and twigs of Streblus asper collected in Vietnam, with the absolute configuration of 1 established from analysis of its ECD and NMR spectroscopic data and confirmed by computational ECD calculations. A new 14,21-epoxycardanolide (3a) was synthesized from 3 that was treated with base. A preliminary structure-activity relationship study indicated that the C-14 hydroxy group and the C-17 lactone unit and the established conformation are important for the mediation of the cytotoxicity of 3. Molecular docking profiles showed that the cytotoxic 3 and its non-cytotoxic analogue 1 bind differentially to Na+/K+-ATPase. Compound 3 docks deeply in the Na+/K+-ATPase pocket with a sole pose, and its C-10 formyl and C-5, C-14, and C-4' hydroxy groups may form hydrogen bonds with the side-chains of Glu111, Glu117, Thr797, and Arg880 of Na+/K+-ATPase, respectively. However, 1 fits the cation binding sites with at least three different poses, which all depotentiate the binding between 1 and Na+/K+-ATPase. Thus, 3 was found to inhibit Na+/K+-ATPase, but 1 did not. In addition, the cytotoxic and Na+/K+-ATPase inhibitory 3 did not affect glucose uptake in human lung cancer cells, against which it showed potent activity, indicating that this cardiac glycoside mediates its cytotoxicity by targeting Na+/K+-ATPase but not by interacting with glucose transporters.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Glicósidos Cardíacos/farmacología , Inhibidores Enzimáticos/farmacología , Moraceae/química , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Glicósidos Cardíacos/química , Glicósidos Cardíacos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Flores/química , Humanos , Conformación Molecular , Simulación del Acoplamiento Molecular , Hojas de la Planta/química , Tallos de la Planta/química , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Relación Estructura-Actividad
10.
Chem Commun (Camb) ; 55(99): 15000-15003, 2019 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-31777880

RESUMEN

Reported herein is a novel p-quinone methide-based self-immobilizing fluorogenic probe for the visualization of ß-galactosidase activities in live cells. This easily prepared imaging reagent massively increases the fluorescence intensity and covalently links to the activation site with high efficiency upon enzymatic trigger.


Asunto(s)
Colorantes Fluorescentes/metabolismo , Indolquinonas/metabolismo , beta-Galactosidasa/metabolismo , Células HEK293 , Células HeLa , Humanos , Metilación , Espectrometría de Fluorescencia
11.
Nat Prod Res ; 33(1): 101-107, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29430943

RESUMEN

A new phenolic derivative, 4-hydroxyphenol-1-O-[6-O-(E)-feruloyl-ß-d-glucopyranosyl]-(1→6)-ß-d-glucopyranoside (1), and a new terpenylated coumarin, named altissimacoumarin H (2) were identified from the fruit of Ailanthus altissima (Mill.) Swingle (Simaroubaceae), together with ten known compounds (3-12), including two coumarins and eight phenylpropanoids. Their structures were determined on the basis of chemical method and spectroscopic data. Antiviral effect against Tobacco mosaic virus (TMV) of all the compounds obtained were evaluated using leaf-disc method.


Asunto(s)
Ailanthus/química , Antivirales/farmacología , Cumarinas/aislamiento & purificación , Frutas/química , Antivirales/aislamiento & purificación , Cumarinas/química , Fenoles/análisis , Fenoles/aislamiento & purificación , Hojas de la Planta/virología , Virus del Mosaico del Tabaco/efectos de los fármacos
12.
Curr Biol ; 28(17): 2853-2860.e3, 2018 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-30146153

RESUMEN

Highly specialized animals are often difficult to place phylogenetically. The Late Cretaceous members of Alvarezsauria represent such an example, having been posited as members of various theropod lineages, including birds [1-11]. A 70-million-year ghost lineage exists between them and the Late Jurassic putative alvarezsaurian Haplocheirus [12], which preserves so few derived features that its membership in Alvarezsauria has recently been questioned [13]. If Haplocheirus is indeed an alvarezsaurian, then the 70-million-year gap between Haplocheirus and other alvarezsaurians represents the longest temporal hiatus within the fossil record of any theropod subgroup [14]. Here we report two new alvarezsaurians from the Early Cretaceous of Western China that document successive, transitional stages in alvarezsaurian evolution. They provide further support for Haplocheirus as an alvarezsaurian and for alvarezsaurians as basal maniraptorans. Furthermore, they suggest that the early biogeographic history of the Alvarezsauria involved dispersals from Asia to other continents. The new specimens are temporally, morphologically, and functionally intermediate between Haplocheirus and other known alvarezsaurians and provide a striking example of the evolutionary transition from a typical theropod forelimb configuration (i.e., the relatively long arm and three-digit grasping hand of typical tetanuran form in early-branching alvarezsaurians) to a highly specialized one (i.e., the highly modified and shortened arm and one-digit digging hand of Late Cretaceous parvicursorines such as Linhenykus [1, 15]). Comprehensive analyses incorporating data from these new finds show that the specialized alvarezsaurian forelimb morphology evolved slowly and in a mosaic fashion during the Cretaceous.


Asunto(s)
Evolución Biológica , Dinosaurios/anatomía & histología , Fósiles , Animales
13.
J Agric Food Chem ; 66(28): 7347-7357, 2018 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-29953225

RESUMEN

Quassinoids are bitter constituents characteristic of the family Simaroubaceae. A total of 18 C20 quassinoids, including nine new quassinoid glycosides, named chuglycosides A-I (1-6 and 8-10), were identified from the samara of Ailanthus altissima (Mill.) Swingle. All of the quassinoids showed potent anti-tobacco mosaic virus (TMV) activity. A preliminary structure-anti-TMV activity relationship of quassinoids was discussed. The effects of three quassinoids, including chaparrinone (12), glaucarubinone (15), and ailanthone (16), on the accumulation of TMV coat protein (CP) were studied by western blot analysis. Ailanthone (16) was further investigated for its influence on TMV spread in the Nicotiana benthamiana plant.


Asunto(s)
Ailanthus/química , Antivirales/farmacología , Extractos Vegetales/farmacología , Cuassinas/farmacología , Virus del Mosaico del Tabaco/efectos de los fármacos , Antivirales/química , Antivirales/aislamiento & purificación , Enfermedades de las Plantas/virología , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Cuassinas/química , Cuassinas/aislamiento & purificación , Relación Estructura-Actividad , Nicotiana/virología , Virus del Mosaico del Tabaco/fisiología
14.
Sci Bull (Beijing) ; 63(9): 556-563, 2018 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-36658842

RESUMEN

A presumably mostly quadrupedal ankylopollexian iguanodontian, Bayannurosaurus perfectus gen. et sp. nov., is reported here, and is represented by an excellently well-preserved skeleton from the Lower Cretaceous Bayingebi Formation of Inner Mongolia, China. The diagnosis of the taxon includes several autapomorphies, notably a dorsally directed, strap-like posterodorsal process of the jugal and a horizontally oriented preacetabular process of the ilium. The nearly complete caudal series retains eight posterior-most caudals with procoelous, trapezoidal centra in dorsal view, and the last three caudals are fully fused. The discovery of B. perfectus opens a critical new window on the early evolution and intercontinental dispersal of Iguanodontia. The skeleton displays a transitional morphology between non-hadrosauriform ankylopollexians and Hadrosauriformes. A phylogenetic analysis indicates that Bayannurosaurus is positioned higher on the tree than Hypselospinus, but below Ouranosaurus just outside of Hadrosauriformes. The tree topology of Iguanodontia with temporal and spatial constraints reveals a possible biogeographic scenario supported by the statistical dispersal-vicariance analysis: around the J/K boundary, non-hadrosauriform ankylopollexians experienced multiple dispersal events from Europe to Asia, accompanying the coeval fall of the global sea level.

15.
Molecules ; 22(12)2017 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-29207525

RESUMEN

Four novel compounds-two phenylpropionamides, one piperidine, and one phenolic derivatives-were isolated and identified from the fruit of a medicinal plant, Ailanthus altissima (Mill.) Swingle (Simaroubaceae), together with one known phenylpropionamide, 13 known phenols, and 10 flavonoids. The structures of the new compounds were elucidated as 2-hydroxy-N-[(2-O-ß-d-glucopyranosyl)phenyl]propionamide (1), 2-hydroxy-N-[(2-O-ß-d-glucopyranosyl-(1→6)-ß-d-glucopyranosyl)phenyl]propionamide (2), 2ß-carboxyl-piperidine-4ß-acetic acid methyl ester (4), and 4-hydroxyphenyl-1-O-[6-(hydrogen-3-hydroxy-3-methylpentanedioate)]-ß-d-glucopyranoside (5) based on spectroscopic analysis. All the isolated compounds were evaluated for their inhibitory activity against Tobacco mosaic virus (TMV) using the leaf-disc method. Among the compounds isolated, arbutin (6), ß-d-glucopyranosyl-(1→6)-arbutin (7), 4-methoxyphenylacetic acid (10), and corilagin (18) showed moderate inhibition against TMV with IC50 values of 0.49, 0.51, 0.27, and 0.45 mM, respectively.


Asunto(s)
Ailanthus/química , Amidas/química , Frutas/química , Fenoles/química , Piperidinas/química , Extractos Vegetales/química , Flavonoides/química
16.
Molecules ; 22(12)2017 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-29186928

RESUMEN

The fermentation and isolation of metabolites produced by an endophytic fungus, which was identified as Phomopsis sp. FJBR-11, based on phylogenetic analysis, led to the identification of six compounds, including dothiorelones A-C, and H, and cytosporones C and U. Among these compounds, cytosporone U exhibited potent inhibitory activity against Tobacco mosaic virus (TMV). Moreover, the crude and a purified exopolysaccharide were proved to possess strong inhibitory effects against the virus infection.


Asunto(s)
Antivirales/farmacología , Ascomicetos/metabolismo , Polisacáridos Bacterianos/farmacología , Virus del Mosaico del Tabaco/efectos de los fármacos , Antivirales/aislamiento & purificación , Antivirales/metabolismo , Ascomicetos/química , Descubrimiento de Drogas , Fermentación , Humanos , Filogenia , Polisacáridos Bacterianos/aislamiento & purificación , Polisacáridos Bacterianos/metabolismo , Metabolismo Secundario , Relación Estructura-Actividad
17.
Sci Rep ; 7(1): 16247, 2017 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-29176627

RESUMEN

The Oviraptorosauria are a group of theropod dinosaurs that diverged from the typical carnivorous theropod diet. It includes two main lineages - Caenagnathidae and Oviraptoridae - that display a number of differences in mandibular morphology, but little is known about their functional consequences, hampering our understanding of oviraptorosaurian dietary evolution. This study presents the first in-depth description of the giant toothless mandible of Gigantoraptor, the only well-preserved stemward caenagnathid mandible. This mandible shows the greatest relative beak depth among caenagnathids, which is an adaptation seen in some modern birds for processing harder seeds. The presence of a lingual triturating shelf in caenagnathids more crownward than Gigantoraptor suggests a possible increased specialization towards shearing along this lineage. Like other oviraptorosaurs, the possession of a dorsally convex articular glenoid in Gigantoraptor indicates that propalinal jaw movement was probably an important mechanism for food processing, as in Sphenodon and dicynodonts. Oviraptorid mandibles were more suited for producing powerful bites (e.g. crushing-related) compared to caenagnathids: oviraptorids generally possess a deeper, more downturned beak, a taller coronoid process prominence and a larger medial mandibular fossa. This disparity in caenagnathid and oviraptorid mandible morphology potentially suggests specialization towards two different feeding styles - shearing and crushing-related mechanisms respectively.


Asunto(s)
Evolución Biológica , Dinosaurios/anatomía & histología , Mandíbula/anatomía & histología , Animales , Fósiles/anatomía & histología
18.
Molecules ; 22(9)2017 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-28926959

RESUMEN

A new Erythrina alkaloid glycoside, named erythraline-11ß-O-glucopyranoside, was isolated from the seeds of Erythrina crista-galli L., together with five known Erythrina alkaloids and an indole alkaloid. The structure of the new alkaloid glycoside was elucidated by spectroscopic methods, and all of the compounds were evaluated for their antiviral activity against tobacco mosaic virus.


Asunto(s)
Alcaloides/química , Antivirales/química , Erythrina/química , Glicósidos/química , Extractos Vegetales/química , Alcaloides/aislamiento & purificación , Antivirales/aislamiento & purificación , Cromatografía Liquida/métodos , Glicósidos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/aislamiento & purificación , Semillas/química , Relación Estructura-Actividad , Virus del Mosaico del Tabaco/efectos de los fármacos
19.
J Thorac Dis ; 9(3): E202-E209, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28449504

RESUMEN

Pheochromocytomas are catecholamine-producing neuroendocrine tumors that usually occur in the adrenal medulla or sympathetic paraganglia. Anterior mediastinum involvement with pheochromocytoma is rare and may not present with typical symptoms. Its clinical manifestation may be unclear and a high index of suspicion is required for accurate diagnosis. We report a rare case of pheochromocytoma of the anterior mediastinum in a 51-year-old female. A painful hard mass on the sternum was the only clinical manifestation. Imageological examination indicated that there might be a malignant mass on the anterior mediastinum and thoracic wall. The patient accepted surgical curettage and thoracic wall reconstruction. Based on pathological results and WHO definition, the final diagnosis was malignant pheochromocytoma. After six months follow-up, the patient had no recurrence or any symptom. Malignant pheochromocytoma in the anterior mediastinum invading the sternum is rare. A local painful mass may be the only clinical manifestation without special laboratory results. Surgery remains as the first choice for these patients. For this rare case, 3D reconstruction by special software may be a good method to realize individualized treatment. The final decision of the diagnosis should be based on pathological results, past medical history and WHO definition. Long-term follow-up is necessary, while other suspicious lesions should also be given sufficient attention.

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