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1.
J Org Chem ; 89(12): 8334-8341, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38860473

RESUMEN

Here, a Cu2(OH)2CO3-catalyzed hydroboration reaction of 1,1-disubstituted α,ß-unsaturated compounds has been developed. The reaction was carried out using water as a solvent at room temperature except for N-monosubstituted α,ß-unsaturated amides. This method is applicable to diverse 1,1-disubstituted α,ß-unsaturated ketones, esters, and amides, showing excellent reactivity (up to 98% yield). Gram-scale experiments and functional group transformations further demonstrated the practicality of this method.

2.
Int J Biol Macromol ; 268(Pt 1): 131205, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38643922

RESUMEN

A series of new kind green cellulose-supported bimetallic TiO2/Cu2O (Cell@TiO2/Cu2O) catalytic materials were obtained by in-situ reduction method employing cellulose as the carrier. The effects of metal percentage composition on the morphology and construction of the catalytic materials were systematically investigated. The Cell@TiO2/Cu2O were characterized by FT-IR, TG, XPS, SEM, TEM, EDS, and the element content was obtained by elemental analysis. Then, the achieved catalytic materials were applied to the chiral borylation reaction of α,ß-unsaturated compounds, including nitrile compounds, esters, and α,ß-unsaturated ketones. Remarkably, this approach provides an efficient strategy to gain an important class of chiral organic boron compounds with target chiral products in high yields as well as enantioselectivities. Besides, the Cell@TiO2/Cu2O could be easily recycled and effectively reused. This work constructed bimetallic TiO2/Cu2O on cellulose as a newly catalyst to obtain chiral boron compounds in aqueous phase.


Asunto(s)
Celulosa , Cobre , Titanio , Titanio/química , Cobre/química , Celulosa/química , Catálisis , Agua/química , Compuestos de Boro/química
3.
Molecules ; 28(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37513482

RESUMEN

A chitosan/poly(vinyl alcohol)-stabilized copper nanoparticle (CP@Cu NPs) was used as a heterogeneous catalyst for the borylation of α, ß-unsaturated ketones, MBH alcohols, and MBH esters in mild conditions. This catalyst not only demonstrated remarkable efficiency in synthesizing organoboron compounds but also still maintained excellent reactivity and stability even after seven recycled uses of the catalyst. This methodology provides a gentle and efficient approach to synthesize the organoboron compounds by efficiently constructing carbon-boron bonds.

4.
J Genet ; 1022023.
Artículo en Inglés | MEDLINE | ID: mdl-36722223

RESUMEN

The objective of the study was to perform the prenatal diagnosis of two foetuses with 22q11.2 duplication for 2.5 Mb after noninvasive prenatal testing (NIPT), and to explore the prenatal diagnosis and genetic characteristics of these foetuses. After amniocentesis, each foetus was diagnosed through karyotype analysis and single-nucleotide polymorphism array (SNP-array), and copy number variation using shotgun sequencing (CNV-seq) was carried out on each mother's peripheral blood for comparative analysis. Both pregnant woman 1 and pregnant woman 2 had foetal amniotic fluid chromosomal karyotypes of 46, XN. The SNP-array result for foetus 1 was arr[hg19] 22q11.21(18,648,856-21,800,471) x3; namely, 22q11.2 had a 3.1 Mb repeat, and the SNP-array result of foetus 2 was arr[hg19]22q11.2(18,648,855-21,464,764) x3; there was a 2.4 Mb repeat of 22q11.2. The CNV-Seq result of the peripheral blood of pregnant woman 1 was seq[hg19]22q11.2(18,953,139-21,449,967) x3; namely, in this mother's 22q11.2 region, there was ~2.5 Mb of duplicate fragment that was pathogenic to CNV. We confirmed that case 1 was inherited from the mother by CNV-seq. In both cases, however, there were key region deletions, including 41 OMIM genes such as CLTCL1, HIRA and TBX1. Both SNP-array and CNV-seq can effectively diagnose 22q11.2 duplication syndrome and clarify its fracture site and involved genes, which may facilitate understanding of the genotype and phenotype correlations.


Asunto(s)
Variaciones en el Número de Copia de ADN , Síndrome de DiGeorge , Femenino , Humanos , Embarazo , Síndrome de DiGeorge/diagnóstico , Síndrome de DiGeorge/genética , Genotipo , Diagnóstico Prenatal
5.
Molecules ; 27(22)2022 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-36432064

RESUMEN

Here, we describe the preparation of copper nanoparticles that are stabilized on a chitosan composite film (CP@Cu). This material could catalyze the 1,6-hydroboration reactions of p-quinone methides with B2pin2 as a boron source under mild conditions. This reaction exhibited very good functional group compatibility, and the organoboron compounds that were formed could easily be converted into corresponding hydroxyl products with good to excellent yields. This newly developed methodology provides an efficient and sequential pathway for the synthesis of gem-disubstituted methanols.


Asunto(s)
Quitosano , Indolquinonas , Nanopartículas , Cobre
6.
Macromol Rapid Commun ; 43(20): e2200403, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35926148

RESUMEN

The morphology transition from primary to hierarchical adsorption-type microporous domains of amphiphilic block copolymer (BCP) honeycomb-structured films is demonstrated by a facile swollen based breath figure (BF) method. The characteristic parameters of poly(4-vinylpyridine)-block-polystyrene (P4VP-b-PS) hierarchical micro- and submicroporous films can be controlled by changing the length of segments or subsequent swelling conditions. A plausible mechanism is demonstrated in this research. A typical amphiphilic BCP with very low volume content of hydrophilic blocks (fP4VP ≤ 0.050) can efficiently stabilize water droplets and inherently assist in the formation of morphology transition. This BCP film can be used for Cr(VI) removal from wastewater, which additionally has enormous potential application in the field of novel optical devices, soft lithography, size-selective separation, etc.

7.
Mol Med Rep ; 22(4): 2665-2672, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32945384

RESUMEN

Oxidative stress induces the formation of oxidized low­density lipoprotein (ox­LDL), which accelerates the development of atherosclerosis and the rupture of atherosclerotic plaques by promoting lipid accumulation and inhibiting autophagy in vascular cells. Lipophagy is known to be involved in maintaining the balance of neutral lipid metabolism; however, the phenomenon of lipophagy deficiency in ox­LDL­treated endothelial cells (ECs) remains to be elucidated. It has been demonstrated that lipid accumulation caused by ox­LDL inhibits autophagy, which promotes apoptosis in ECs. The aim of the present study was to investigate the association between decreased autophagy and lipid accumulation in ECs treated with ox­LDL. Electron microscopy demonstrated that the formation of autolipophagosomes was decreased in ox­LDL­treated human umbilical vein ECs compared with that in the LDL­treated group and was accompanied by a decrease in the autophagy­associated proteins via western blotting analysis. Using laser focal colocalization detection, decreased lipid processing was observed in the lysosomes of ox­LDL­treated ECs, which indicated that lipophagy may be attenuated and subsequently result in lipid accumulation in ox­LDL­treated ECs.


Asunto(s)
Autofagia/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/citología , Lipoproteínas LDL/efectos adversos , Línea Celular , Supervivencia Celular , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Metabolismo de los Lípidos , Microscopía Electrónica , Estrés Oxidativo/efectos de los fármacos
8.
J Membr Biol ; 253(2): 101-108, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32140737

RESUMEN

As a member of the kinesin-3 family, kinesin family member 16B (KIF16B) has a characteristic PhoX homology (PX) domain that binds to membranes containing phosphatidylinositol-3-phosphate (PI(3)P) and moves along microtubule filaments to the plus end via a process regulated by coiled coils in the stalk region in various cell types. The physiological function of KIF16B supports the transport of intracellular cargo and the formation of endosomal tubules. Ras-related protein (Rab) coordinates many steps of membrane transport and are involved in the regulation of KIF16B-mediated vesicle trafficking. Data obtained from clinical research suggest that KIF16B has a potential effect on the disease processes in intellectual disability, abnormal lipid metabolism, and tumor brain metastasis. In this review, we summarize recent advances in the structural and physiological characteristics of KIF16B as well as diseases associated with KIF16B disorders, and speculating its role as a potential adaptor for intracellular cholesterol trafficking.


Asunto(s)
Cinesinas/química , Cinesinas/metabolismo , Microtúbulos/metabolismo , Dominios y Motivos de Interacción de Proteínas , Animales , Proteínas Portadoras/metabolismo , Membrana Celular/metabolismo , Susceptibilidad a Enfermedades , Humanos , Espacio Intracelular/metabolismo , Unión Proteica , Transporte de Proteínas , Relación Estructura-Actividad
9.
Med Hypotheses ; 136: 109524, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31862687

RESUMEN

Human health is threatened by obesity which causes the increasing incidence of various diseases, especially stroke. Ischemic stroke (IS) is mostly caused by the rupture of arterial plaque, whose instability is positively associated with matrix metalloproteinases (MMPs) that degrades extracellular matrix components. Studies have shown that matrix metalloproteinase-12 (MMP-12) may be involved in the pathogenesis of IS. Because of the higher incidence of stroke in obese patients than that in normal weight people, it is urgent for obesity to forecast stroke early. Considering high levels MMP-12 in obesity, we put forward that MMP-12 may be a potential biomarker for IS in obese patients.


Asunto(s)
Isquemia Encefálica/diagnóstico , Accidente Cerebrovascular Isquémico/diagnóstico , Metaloproteinasa 12 de la Matriz/metabolismo , Obesidad/fisiopatología , Animales , Apoptosis , Biomarcadores/metabolismo , Isquemia Encefálica/complicaciones , Humanos , Incidencia , Inflamación , Accidente Cerebrovascular Isquémico/complicaciones , Longevidad , Obesidad/complicaciones , Trombina/metabolismo
10.
Nanotechnology ; 30(36): 364003, 2019 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-31100750

RESUMEN

All-solid-state Li-O2 batteries are receiving intense interest because of the substitution of solid electrolytes for toxic and flammable liquid electrolytes. However, new issues are arising in the aspect of the electrolyte cathode interface. On the one hand, in a traditional sandwiched battery structure, the reaction sites of the cathode are restricted to the finite planar electrode-electrolyte interface, resulting in limited performance of all-solid-state Li-O2 batteries. On the other hand, integrating the electrolyte with the cathode to achieve good interfacial contact often requires complex sintering processes. Herein, this work reports a solid electrolyte cathode assembly (SECA) which consists of a dense Li1.5Al0.5Ge1.5P3O12 (LAGP) layer and a carbon coated porous LAGP layer fabricated by facilely one-step sintering. As a result, Li-O2 batteries adopting the SECA showed a relatively high discharge capacity of 0.48 mAh cm-2 at 5 µA cm-2. Besides, the batteries could sustain six full cycles with a restricted capacity of 0.08 mAh cm-2 at 10 µA cm-2. It was found that the high capacity can be attributed to the high surface area of porous cathode structure.

11.
Nanomaterials (Basel) ; 8(5)2018 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-29757981

RESUMEN

We describe here the preparation of copper nanoparticles stabilized on a chitosan/poly (vinyl alcohol) composite film. This material could catalyze the borylation of α,ß-unsaturated acceptors in aqueous media under mild conditions. The corresponding organoboron compounds as well as their converted ß-hydroxyl products were all obtained in good to excellent yields. It is noteworthy that this catalyst of copper nanoparticles can be easily recycled eight times and remained catalytically reactive. This newly developed methodology provides an efficient and sustainable pathway for the synthesis of organoboron compounds and application of copper nanoparticles.

12.
Polymers (Basel) ; 10(4)2018 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-30966420

RESUMEN

The first example of an environmentally-benign chitosan supported copper catalyzed conjugate silylation of α,ß-unsaturated acceptors was accomplished in water under mild conditions. This protocol provides an efficient pathway to achieve an important class of ß-silyl carbonyl compounds and the desired products were obtained in good to excellent yields. Gram-scale synthesis and easy transformation of obtained ß-silyl products were also been demonstrated. Remarkably, this chitosan supported copper catalyst can be easily recycled and reused six times without any significant decrease of catalytic activity. The advantages of this newly developed method include operational simplicity, good functional group tolerance, scale-up ability, ready availability, and easy recyclability of catalyst.

13.
Chem Commun (Camb) ; 52(38): 6371-4, 2016 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-26996326

RESUMEN

We report herein a single component Ir photoredox catalyst which is capable of catalyzing the hydrotrifluoromethylation of terminal alkenes and Michael acceptors with sodium triflinate (Langlois reagent) in methanol under irradiation at room temperature. Various synthetically useful functional groups, including ester, amide, ether, aldehyde, sulfone, ketone and aryl boronate, are well tolerated in this reaction.

14.
Int J Biol Macromol ; 83: 442-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26454108

RESUMEN

Lead-induced oxidative stress was generated in mice under lead exposure, and the antioxidant activity of chitosan (CS) and its water-soluble derivatives was compared in vivo. The results indicated that there was significant difference (P<0.05) for the biochemical variables of lead-treated groups. After lead exposure, the contents of reduced glutathione (GSH) and total thiols (T-SH) in blood and tissues decreased, and the contents of protein oxidation, oxidized glutathione (GSSG), malondialdehyde (MDA) and reactive oxygen species (ROS) increased compared with the control group. Administration of CS and its derivatives made for the removal of lead from blood and tissues, especially for hydroxypropyl chitosan (HPCS) and quaternary ammonium salt of chitosan (HACC). And the changed biochemical variables showed recovery with different degrees, which indicated that CS and its derivatives were helpful for alleviating lead-induced oxidation damage in vivo. But the antioxidant activity for different CS was different, followed by HPCS>HACC>carboxymethyl chitosan (CMCS)>CS, which was in close with the introduction of different substituent groups. In particular, for the dietary of HPCS, there was significant recovery for the changed biochemical variables (P<0.05) in mice after lead exposure, except GSSG in kidney and MDA in brain.


Asunto(s)
Quitosano/química , Quitosano/farmacología , Plomo/toxicidad , Estrés Oxidativo/efectos de los fármacos , Agua/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Peso Corporal/efectos de los fármacos , Contaminantes Ambientales/sangre , Contaminantes Ambientales/metabolismo , Contaminantes Ambientales/toxicidad , Femenino , Glutatión/sangre , Plomo/sangre , Plomo/metabolismo , Ratones , Tamaño de los Órganos/efectos de los fármacos , Especificidad de Órganos , Solubilidad , Compuestos de Sulfhidrilo/sangre
15.
ACS Appl Mater Interfaces ; 7(31): 17307-10, 2015 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-26177186

RESUMEN

The all-solid-state Li-air battery has been fabricated, which is constructed by a lithium foil anode, a NASICON-type solid state electrolyte Li1+xAlyGe2-y(PO4)3 (LAGP) and single-walled carbon nanotubes (SWCNTs)/LAGP nanoparticles composite as air electrode. Its electrochemical performance was investigated in air atmosphere. Particularly, this battery exhibited a larger capacity about 2800 mAh g(-1) for the first cycle, while comparatively the battery with multiwalled carbon nanotubes (MWCNTs)/LAGP as cathode had a capacity of only about 1700 mAh g(-1). Also, the battery with SWCNTs/LAGP showed improved cycling performance with a reversible capacity of 1000 mAh g(-1) at a current density of 200 mA g(-1). Our result demonstrated that the all-solid-state Li-air battery with SWCNTs/LAGP as cathode catalyst has a considerable potential for practical application.

16.
Solid State Nucl Magn Reson ; 66-67: 29-32, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25616847

RESUMEN

Paramagnetic relaxation enhancement solid-state NMR (PRE ssNMR) technique was used to investigate catalytic reaction over zeolite HY. After introducing paramagnetic Cu(II) ions into the zeolite, the enhancement of longitudinal relaxation rates of nearby nuclei, i.e.(29)Si of the framework and (13)C of the absorbents, was measured. It was demonstrated that the PRE ssNMR technique facilitated the fast acquisition of NMR signals to monitor the heterogeneous catalytic reaction (such as acetone to hydrocarbon) using natural abundance reactants.

17.
Chem Commun (Camb) ; 48(55): 6936-8, 2012 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-22673709

RESUMEN

Solid-state NMR and DFT calculation studies certified the presence of an intermolecular solvent effect for molecules confined in microporous zeolite, leading to a notable increase in Brønsted acidity of the solid acid catalyst.

18.
Angew Chem Int Ed Engl ; 51(16): 3850-3, 2012 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-22389151

RESUMEN

Two ways: a Zn-modified ZSM-5 zeolite catalyst was developed for the reaction of methane with carbon monoxide to directly produce acetic acid under mild conditions (573-623 K), and two different intermediate-dependent reaction pathways were unambiguously identified for acetic acid formation by in situ solid-state NMR spectroscopy.

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