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1.
Theriogenology ; 218: 137-141, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38325150

RESUMEN

The present experiments are aimed to examine the effect of copper nanoparticles supported on charcoal (CuNPs/C), growth factor betacellulin (BTC) and their interrelationships in the control of ovarian cell functions. Porcine ovarian granulosa cells were cultured in the presence of CuNPs/C (0, 1, 10 or 100 ng/ml), BTC (100 ng/ml) and the combination of both, CuNPs/C + BTC. Markers of cell proliferation (BrDU incorporation), of the S-phase (PCNA) and G-phase (cyclin B1) of the cell cycle, markers of extrinsic (nuclear DNA fragmentation) and cytoplasmic/mitochondrial apoptosis (bax and caspase 3), and the release of progesterone and estradiol were assessed by BrDU test, TUNEL, quantitative immunocytochemistry and ELISA. Both CuNPs/C and BTC, when added alone, increased the expression of all the markers of cell proliferation, reduced the expression of all apoptosis markers and stimulated progesterone and estradiol release. Moreover, BTC was able to promote the CuNPs/C action on the accumulation of PCNA, cyclin B1, bax and estradiol output. These observations demonstrate the stimulatory action of both CuNPs/C and BTC on ovarian cell functions, as well as the ability of BTC to promote the action of CuNPs/C on ovarian cell functions.


Asunto(s)
Nanopartículas , Progesterona , Femenino , Porcinos , Animales , Ciclina B1/metabolismo , Progesterona/farmacología , Carbón Orgánico/metabolismo , Carbón Orgánico/farmacología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Betacelulina/metabolismo , Betacelulina/farmacología , Bromodesoxiuridina/metabolismo , Bromodesoxiuridina/farmacología , Células de la Granulosa , Estradiol/farmacología , Proliferación Celular , Apoptosis , Células Cultivadas , Factor I del Crecimiento Similar a la Insulina/metabolismo
2.
Molecules ; 27(22)2022 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-36431891

RESUMEN

One way to exploit CO2 is to use it as a feedstock for the production of cyclic carbonates via its reaction with organic epoxides. As far as we know, there is still no heterogeneous catalyst that accelerates the reaction in a selective, efficient and industrially usable way. Cobalt and zinc-based zeolitic imidazole frameworks (ZIFs) have been explored as heterogeneous catalysts for this reaction. In particular, we have prepared ZIF-8 and ZIF-67 catalysts, which have been modified by partial replacement of 2-methylimidazole by 1,2,4-triazole, in order to introduce uncoordinated nitrogen groups with the metal. The catalysts have shown very good catalytic performance, within the best of the heterogeneous catalysts tested in the cycloaddition of CO2 with epichlorohydrin. The catalytic activity is due ultimately to defects on the outer surface of the crystal, and varies in the order of ZIF-67-m > ZIF-67 > ZiF-8-m = ZIF-8. Notably, reactions take place under mild reaction conditions and without the use of co-catalysts.

3.
Photochem Photobiol Sci ; 21(8): 1473-1479, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35583722

RESUMEN

Selective semi-oxidation of tetrahydroisoquinoline (THIQ) leads to a valuable dihydroisoquinoline (DHIQ) derivative via singlet oxygen photooxidation process. Typical photosensitisers (i.e., Ru complexes) can activate the reaction even under heterogeneous conditions that facilitate catalyst separation and reusability. In contrast to DHIQ, THIQ acts as an efficient singlet oxygen quencher driving the reaction selectivity. The reaction can also be facilitated by semiconductor catalysts such as MoCo@GW, a glass wool-based catalyst that is easy to separate and reuse and compatible with flow photochemistry. Its role is to mediate the formation of isoquinoline (IQ) and thus an in situ-generated singlet oxygen catalyst. Laser flash photolysis with NIR detection provides proof of the singlet oxygen mechanism proposed and rate constants for the key steps that mediate the oxidation.


Asunto(s)
Oxígeno Singlete , Tetrahidroisoquinolinas , Cinética , Oxidación-Reducción , Oxígeno , Fotoquímica , Oxígeno Singlete/química
4.
Nanomaterials (Basel) ; 10(9)2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32957511

RESUMEN

The application of nanoparticles has experienced a vertiginous growth, but their interaction with food and medicinal plants in organisms, especially in the control of reproduction, remains unresolved. We examined the influence of copper nanoparticles supported on titania (CuNPs/TiO2), plant extracts (buckwheat (Fagopyrum esculentum) and vitex (Vitex agnus-castus)), phytochemicals (rutin and apigenin), and their combination with CuNPs/TiO2 on ovarian cell functions, using cultured porcine ovarian granulosa cells. Cell viability, proliferation (PCNA accumulation), apoptosis (accumulation of bax), and hormones release (progesterone, testosterone, and 17ß-estradiol) were analyzed by the Trypan blue test, quantitative immunocytochemistry, and ELISA, respectively. CuNPs/TiO2 increased cell viability, proliferation, apoptosis, and testosterone but not progesterone release, and reduced the 17ß-estradiol output. Plant extracts and components have similar stimulatory action on ovarian cell functions as CuNPs/TiO2, but abated the majority of the CuNPs/TiO2 effects. This study concludes that (1) CuNPs/TiO2 can directly stimulate ovarian cell functions, promoting ovarian cell proliferation, apoptosis, turnover, viability, and steroid hormones release; (2) the plants buckwheat and vitex, as well as rutin and apigenin, can promote some of these ovarian functions too; and (3) these plant additives mitigate the CuNPs/TiO2's activity, something that must be considered when applied together.

5.
Nanotoxicology ; 14(5): 683-695, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32189538

RESUMEN

The aim of this survey is to explore the possible effects of unsupported and supported copper nanoparticles (CuNPs) of different morphologies on basic ovarian cell functions. For this purpose, we have compared the activity of unsupported spherical, triangular, and hexagonal CuNPs, as well as of spherical CuNPs supported on titania, zeolite Y and activated charcoal (0, 1, 10, or 100 ng/mL) on cultured porcine ovarian granulosa cells. Cell viability, proliferation (accumulation of proliferating cell nuclear antigen, PCNA), apoptosis (accumulation of Bcl-2-associated X protein, bax) and release of steroid hormones progesterone, testosterone, and 17ß-estradiol have been analyzed by the Trypan blue test, quantitative immunocytochemistry, and ELISA, respectively. Cell viability decreased after treatment with hexagonal CuNPs, whilst all the other CuNPs increased it. Unsupported spherical and hexagonal CuNPs, and spherical CuNPs/titania reduced PCNA accumulation; in contrast, an increase was noted for unsupported triangular CuNPs and CuNPs/zeolite Y. Bax accumulation was not affected by hexagonal CuNPs, whereas CuNPs/zeolite Y promoted it and all the other CuNPs depleted it. The release of all steroid hormones was inhibited by CuNPs/titanium dioxide and stimulated by CuNPs/charcoal, whilst CuNPs/zeolite Y promoted the testosterone and 17ß-estradiol output, but not that of progesterone. These results demonstrate the direct, mainly stimulatory, impact of CuNPs on basic ovarian cell functions. The character of the CuNPs' action depends on their shape and support. Therefore, CuNPs with appropriate chemical modification could be potentially useful for the control of reproductive processes and treatment of reproductive disorders.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Cobre/química , Cobre/toxicidad , Hormonas Gonadales/metabolismo , Células de la Granulosa/efectos de los fármacos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Carbón Orgánico/química , Relación Dosis-Respuesta a Droga , Femenino , Células de la Granulosa/metabolismo , Células de la Granulosa/fisiología , Ovario/metabolismo , Ovario/patología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Propiedades de Superficie , Porcinos , Titanio/química , Zeolitas/química
6.
Chemistry ; 24(71): 18857-18862, 2018 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-30325078

RESUMEN

Lately, the cross-dehydrogenative coupling of tetrahydroisoquinolines and nitroalkanes has become a widely studied reaction in organic chemistry; the corresponding ß-nitroamines are generally formed irrespective of the catalysis and activation mode utilized. A quite distinct behavior was observed when the reaction was catalyzed by copper nanoparticles supported on titania, leading to the formation of 5,6-dihydroindolo[2,1-a]isoquinolines with high selectivity and good yields. A meticulous reaction mechanism is proposed, based on experimentation, and discussed along with a key chemical modification of these compounds. Apparently, the catalyst effectiveness resides in its nanostructured character, outperforming the activity of the commercial copper catalysts.

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