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1.
Nano Lett ; 22(3): 1190-1197, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35043640

RESUMEN

Construction of lateral junctions is essential to generate one-dimensional (1D) confined potentials that can effectively trap quasiparticles. A series of remarkable electronic phases in one dimension, such as Wigner crystallization, are expected to be realized in such junctions. Here, we demonstrate that we can precisely tune the 1D-confined potential with an in situ manipulation technique, thus providing a dynamic way to modify the correlated electronic states at the junctions. We confirm the existence of 1D-confined potential at the homojunction of two single-layer 1T-NbSe2 islands. Such potential is structurally sensitive and shows a nonmonotonic function of their interspacing. Moreover, there is a change of electronic properties from the correlated insulator to the generalized 1D Wigner crystallization while the confinement becomes strong. Our findings not only establish the capability to fabricate structures with dynamically tunable properties, but also pave the way toward more exotic correlated systems in low dimensions.

2.
J Prosthet Dent ; 2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36610845

RESUMEN

STATEMENT OF PROBLEM: According to the concept of implant-protected occlusion, light occlusion and late contact could prevent implants from occlusal overload. However, clinical data demonstrating how light occlusion differs from normal occlusion are lacking. PURPOSE: The purpose of this prospective clinical study was to characterize the occlusal variation of single posterior implant-supported crowns with or without light occlusion. MATERIAL AND METHODS: Participants with a single missing posterior maxillary or mandibular molar who were to receive implant-supported zirconia ceramic crowns were enrolled. The participants were divided into a light occlusion group, in which a 12-µm articulating film could be removed from the implant-supported crown and opposing natural teeth under the intercuspal position, and a normal occlusion group, in which the articulating film could not be removed. All participants underwent occlusal examinations using the T-scan III system, answered a satisfaction questionnaire using a visual analog scale (VAS), and received regular follow-ups. The participants were evaluated at 0.5, 3, 6, and 12 months after implant-supported crown delivery. The relative occlusal force of the implant-supported crowns, mesial teeth, control teeth (corresponding natural tooth on the dentition contralateral to each implant), and the occlusal contact time of implant-supported crowns were recorded. Moreover, the asymmetry index of the occlusal force and the VAS score were calculated. Two independent-sample tests were used to compare the 2 groups. The Wilcoxon rank sum and Mann‒Whitney tests were used to compare nonnormally distributed data (α=.001). RESULTS: Fifty study participants with a mean ±standard deviation age of 36.97 ±7.34 years (23 men and 27 women aged 20 to 50 years) were followed for 0.5 to 12 months. No obvious complications of overloading were observed in either group. The mean ±standard deviation of the relative occlusal force of implant-supported crowns in the light occlusion group (from 4.91 ±3.52% to 10.34 ±4.35%) was always lower than that in the normal occlusion group (from 10.45 ±4.32% to 18.15 ±4.80%), while the mean ±standard deviation of the occlusal contact time in the light occlusion group (from 0.38 ±0.26 seconds to 0.10 ±0.07 seconds) was significantly later than that in the normal occlusion group (from 0.12 ±0.08 seconds to 0.04 ±0.02 seconds) (P<.001). The value of the asymmetry index of occlusal force remained within the normal range (10%). The VAS score in the normal occlusion group was significantly higher than that in the light occlusion group (P<.001). CONCLUSIONS: Providing light occlusion to reduce occlusal force and delay the contact time was not stable over time. The relative occlusal force and occlusal contact time showed a similar development trend in both groups, and no obvious signs of occlusal overloading were observed in this study. Long-term follow-up is necessary for implant-supported prostheses because of the continuous increase in occlusal force.

3.
Chemistry ; 27(47): 12215-12223, 2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34060672

RESUMEN

While the integration of supramolecular principles in catalysis attracts increasing attention, a direct comparative assessment of the resulting systems catalysts to work out distinct characteristics is often difficult. Herein is reported how the broad responsiveness of ether cyclizations to diverse inputs promises to fill this gap. Cyclizations in the confined, π-basic and Brønsted acidic interior of supramolecular capsules, for instance, are found to excel with speed (exceeding general Brønsted acid and hydrogen-bonding catalysts by far) and selective violations of the Baldwin rules (as extreme as the so far unique pnictogen-bonding catalysts). The complementary cyclization on π-acidic aromatic surfaces remains unique with regard to autocatalysis, which is shown to be chemo- and diastereoselective with regard to product-like co-catalysts but, so far, not enantioselective.


Asunto(s)
Éter , Catálisis , Ciclización , Enlace de Hidrógeno
4.
Arch Microbiol ; 204(1): 53, 2021 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-34936048

RESUMEN

A Gram-positive strain APA H-16(1)T was isolated from a saline-alkali soil sample collected from Heilongjiang Province, China. Cells were rod shaped, non-motile, endospore forming, and aerobic. Growth occurred at 10-45 °C (optimum, 35 °C), pH 7.0-10.5 (optimum, pH 9.5), and could tolerate NaCl up to 15.0% (w/v). Strain showed low 16S rRNA gene sequence similarities with Alteribacter natronophilus (97.8%), Alteribacter aurantiacus (97.7%), and Alteribacter populi (97.1%). The cell wall peptidoglycan was meso-diaminopimelic acid. The predominant menaquinone was MK-7. The polar lipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, unidentified aminophospholipids, unidentified phospholipid, and unidentified lipid. The major fatty acids were anteiso-C15:0, and iso-C15:0. The genomic G + C content was 45.1%. The average nucleotide identity and digital DNA-DNA hybridization values between strain APA H-16(1)T and the most closely related species were below the cut-off level (95-96%; 70%) for species delineation. Based on phenotypic, phylogenetic, chemotaxonomic, and genome comparison, strain APA H-16(1)T represents a novel species of the genus Alteribacter, for which the name Alteribacter salitolerans sp. nov. is proposed. The type strain is APA H-16(1)T (= KCTC 43228T = CICC 25092T).


Asunto(s)
Microbiología del Suelo , Suelo , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos , Fosfolípidos , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
5.
Arch Microbiol ; 203(3): 959-966, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33104820

RESUMEN

An alkaliphilic actinobacterial strain, designated Hz 6-5T, was isolated from saline-alkaline soil from Songnen Plain in north-eastern China. The isolate formed light yellow-colored colonies and its cells were Gram-staining positive, non-motile, and non-spore-forming short rods. The strain was aerobic with optimal growth at 33 °C, pH 9.0, and in the presence of 0.5% (w/v) NaCl or 3% (w/v) KCl. It was catalase-positive and oxidase-negative. The isolate had highest 16S rRNA gene sequence similarities to the type strains of the species Nesternkonia natronophila M8T (98.2%), N. salmonea GY074T (98.1%), and N. sphaerica GY239T (97.4%), and the isolate formed a subclade with the type strains of these species in the neighbor-joining tree based on the 16S rRNA gene sequences. The phylogenetic tree based on the phylogenomic analysis also showed the same results. The DNA‒DNA relatedness (DDH) values of isolate Hz 6-5T with N. natronophila M8T, N. halophila DSM 16378T, and N. halobia CGMCC 1.2323T were 21.2%, 36.5%, and 32.0%, respectively. The characteristic diamino acid of strain Hz 6-5T was found to be lysine. The respiratory quinones were MK-9, MK-8, MK-7(H4), MK-7(H2) and MK-7 and the major cellular fatty acids (> 10%) were anteiso-C15:0, anteiso-C17:0 and iso-C16:0. The polar lipids detected for strain Hz 6-5T were diphosphatidylglycerol, phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, an unidentified glycolipid, and two unidentified phospholipids. The DNA G + C content of isolate Hz 6-5T was 60.8%. Based on the results of phylogenetic analysis supported by morphological, physiological, chemotaxonomic, and other differentiating phenotypic evidence, strain Hz 6-5T is considered to represent a novel species of the genus Nesterenkonia, for which the name Nesterenkonia haasae sp. nov. is proposed. The type strain is Hz 6-5T (=CPCC 205100T=NBRC 113521T).


Asunto(s)
Micrococcaceae/clasificación , Filogenia , Microbiología del Suelo , Composición de Base , China , Ácidos Grasos/análisis , Glucolípidos/análisis , Micrococcaceae/genética , Micrococcaceae/aislamiento & purificación , Peptidoglicano/química , Fosfolípidos/análisis , ARN Ribosómico 16S/genética , Especificidad de la Especie
6.
Appl Opt ; 60(5): 1164-1170, 2021 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-33690546

RESUMEN

A broadband three-dimensional (3D) mode (de) multiplexer [(De)MUX] is proposed based on the subwavelength grating (SWG) for 3D photonic integrated circuits (PICs). The proposed 3D mode (De)MUX consists of three SWG waveguides on two vertical layers. The coupling strength and operating bandwidth can be increased benefitting from both the subwavelength structure and offset between bus and access SWGs. The proposed 3D mode (De)MUX is optimized based on the 3D full-vectorial finite difference time domain method. The 1-dB bandwidths of the optimized device are over >300, 107, and 128 nm for demultiplexing TE0, TE1, and TE2 modes, respectively. The coupling lengths are only 5.0 and 1.75 µm for demultiplexing the TE1 and TE2 modes, respectively. The insertion losses are 0.12, 0.27, and 0.29 dB, respectively. The proposed 3D mode (De)MUX is also fabrication tolerant.

7.
Biomacromolecules ; 21(9): 3512-3522, 2020 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-32687330

RESUMEN

An efficient process for the synthesis of degradable hydrogels containing octa-betaine ester polyhedral oligomeric silsesquioxane (POSS) through efficient thiol-ene and Menschutkin click reactions was developed. The hydrogels exhibited a yield strength of 0.36 MPa and a compressive modulus of 4.38 MPa and displayed excellent flexibility as well as torsion resistance. Antibacterial efficacy of hydrogels (and degradation products) was evaluated using Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive). Efficacy was found to increase with the concentration of cetyl chloroacetate (CCA) in the hydrogel network, reaching 93% and 99% for Escherichia coli and Staphylococcus aureus, respectively. Degradation of hydrogels was observed in weak alkali conditions (pH = 8) and at physiological conditions (pH = 7.4). The degradation time of the hydrogels could be finely tuned by variation of the CCA content in the hydrogel and environmental stimulus. The tunable degradation behavior under physiological conditions combined with high antibacterial efficacy could render the presented materials interesting for tissue engineering applications.


Asunto(s)
Betaína , Hidrogeles , Antibacterianos/farmacología , Química Clic , Ésteres
8.
Angew Chem Int Ed Engl ; 59(35): 15093-15097, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32181559

RESUMEN

Anion-π catalysis functions by stabilizing anionic transition states on aromatic π surfaces, thus providing a new approach to molecular transformation. The delocalized nature of anion-π interactions suggests that they serve best in stabilizing long-distance charge displacements. Aiming therefore for an anionic cascade reaction that is as charismatic as the steroid cyclization is for conventional cation-π biocatalysis, reported here is the anion-π-catalyzed epoxide-opening ether cyclizations of oligomers. Only on π-acidic aromatic surfaces having a positive quadrupole moment, such as hexafluorobenzene to naphthalenediimides, do these polyether cascade cyclizations proceed with exceptionally high autocatalysis (rate enhancements kauto /kcat >104 m-1 ). This distinctive characteristic adds complexity to reaction mechanisms (Goldilocks-type substrate concentration dependence, entropy-centered substrate destabilization) and opens intriguing perspectives for future developments.

9.
J Am Chem Soc ; 140(51): 17867-17871, 2018 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-30543410

RESUMEN

Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion-π interactions account for function. Rate enhancements maximize at 270 for anion-π catalysis on fullerenes and at 5100 M-1 for autocatalysis. The occurrence of anion-π autocatalysis is confirmed with increasing initial rates in the presence of additional product. Computational studies on autocatalysis reveal transition state and product forming a hydrogen-bonded noncovalent macrocycle, like holding their hands and dancing on the active π surface, with epoxide opening and nucleophile being activated by anion-π interactions and hydrogen bonds to the product, respectively.

10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1670-3, 2016 Jun.
Artículo en Zh | MEDLINE | ID: mdl-30052369

RESUMEN

Scanning Electron Microscope-Energy Dispersive X-ray spectroscopy (SEM-EDX) was applied to analyze the chemical and structural properties of biochars produced under different temperatures. Results showed that average carbon content (SEM C aver.) and maximum carbon content (SEM C max.) of miscanthus (MS) biochar increased as temperature increasing. There were significant and positive relationships between SEM C max., SEM C aver. and highest treatment temperature (HTT) (r were 0.76 and 0.86). SEM C max., SEM C aver. and dry combustion total carbon content had significant and positive relationships (r were 0.83 and 0.91), SEM C max. which was better than SEM C aver. So the carbon content of MS biochar which had good correlationship with temperature analyzed by SEM-EDX, SEM C max. could be used for composition analysis of biochar, scanning results could analyze structural properties of biochar effectively. This method is rapid, simple and stable. It also could analyze structure and composition of biochar simultaneously. It is a promising method that would be useful to study the structure and composition of biochar and other materials.

11.
Angew Chem Int Ed Engl ; 54(1): 241-4, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25382688

RESUMEN

A highly enantioselective Mannich reaction of silyl ketene imines with isatin-derived ketimines has been realized by using a chiral N,N'-dioxide/Zn(II) catalyst. A variety of ß-amino nitriles containing congested vicinal tetrasubstituted stereocenters were obtained with excellent outcomes (up to 98 % yield, >19:1 d.r. and 99 % ee). Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction.


Asunto(s)
Etilenos/química , Iminas/síntesis química , Cetonas/química , Nitrilos/síntesis química , Zinc/química , Aminación , Catálisis , Iminas/química , Nitrilos/química , Estereoisomerismo
12.
Angew Chem Int Ed Engl ; 54(5): 1608-11, 2015 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-25488490

RESUMEN

A catalytic asymmetric intramolecular homologation of simple ketones with α-diazoesters was firstly accomplished with a chiral N,N'-dioxide-Sc(OTf)3 complex. This method provides an efficient access to chiral cyclic α-aryl/alkyl ß-ketoesters containing an all-carbon quaternary stereocenter. Under mild conditions, a variety of aryl- and alkyl-substituted ketone groups reacted with α-diazoester groups smoothly through an intramolecular addition/rearrangement process, producing the ß-ketoesters in high yield and enantiomeric excess.

13.
Compr Psychiatry ; 55(8): 1785-90, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25200194

RESUMEN

BACKGROUND: The reason why it is difficult to identify susceptibility genes attributed to bipolar disorder (BPD) is the phenotypic heterogeneity. The use of endophenotypes has been advocated as one possible strategy to discovery cause variants of BPD. METHODS: A total of 164 patients with BPD and 164 matched controls were employed in the present research. Fifty-two single nucleotide polymorphisms (SNPs) within the genes in serotonin pathway were selected for genotyping using the GoldenGate genotyping assay. All participants completed three neurocognitive tests including the tower of Hanoi (TOH), the Wisconsin card sorting test (WCST) and Trail making tests (TMTA and TMTB-M). RESULTS: Patients with BPD demonstrated a wide range of deficits in mental activities of attention and speed of information processing, and executive function. Significant interactions between rs2760347 in 5HTR2A gene and diagnosis were found for the executive time of TOH, with ß=11.82 and P=0.002 (adjusted P=0.03 after Bonferroni correction). CONCLUSIONS: Cognitive impairments existing in BPD may be particularly notable in certain domains of attention and executive function, and 5HTR2A gene may be involved in modulating executive function of BP-I patients.


Asunto(s)
Atención/fisiología , Trastorno Bipolar/genética , Trastorno Bipolar/fisiopatología , Función Ejecutiva/fisiología , Serotonina/genética , Adulto , Endofenotipos , Femenino , Genotipo , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Transducción de Señal/genética
14.
J Colloid Interface Sci ; 673: 874-882, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38908286

RESUMEN

The quest for efficient hydrogen production highlights the need for cost-effective and high-performance catalysts to enhance the electrochemical water-splitting process. A significant challenge in developing self-supporting catalysts lies in the high cost and complex modification of traditional substrates. In this study, we developed catalysts featuring superaerophobic microstructures engineered on microspherical nickel-coated Chinese rice paper (Ni-RP), chosen for its affordability and exceptional ductility. These catalysts, due to their microspherical morphology and textured surface, exhibited significant superaerophobic properties, substantially reducing bubble adhesion. The nickel oxy-hydroxide (NiOxHy) and phosphorus-doped nickel (PNi) catalysts on Ni-RP demonstrated effective roles in oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), achieving overpotentials of 250 mV at 20 mA cm-2 and 87 mV at -10 mA cm-2 in 1 M KOH, respectively. Moreover, a custom water-splitting cell using PNi/Ni-RP and NiOxHy/Ni-RP electrodes reached an impressive average voltage of 1.55 V at 10 mA cm-2, with stable performance over 100 h in 1 M KOH. Our findings present a cost-effective, sustainable, and easily modifiable substrate that utilizes superaerophobic structures to create efficient and durable catalysts for water splitting. This work serves as a compelling example of designing high-performance self-supporting catalysts for electrocatalytic applications.

15.
Bioresour Technol ; 394: 130273, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38160851

RESUMEN

Four kinds of Fe/N co-doped porous hydrochar were prepared by one/two-step N-doping schemes using microwave/traditional pyrolysis methods for removing Cr(VI) from aqueous phase. Heterocyclic-N was introduced through CO(NH2)2-based hydrothermal carbonization process, which could adjust the electronic structure of the hydrochar framework. Furthermore, Fe0 and Fe3O4 were embedded into hydrochar via carbothermal reduction reaction using FeCl3 as the precursor, which improved the reducibility and magnetism of the material. The modified hydrochar exhibited pH-dependency and rapid kinetic equilibrium, and the maximal adsorption amount of magnetic porous hydrochar obtained by microwave-assisted one-step N-doping (MP1HCMW) reached 274.34 mg/g. Meanwhile, the modified hydrochar had a high tolerance to multiple co-existing ions and the removal efficiency maintained above 73.91 % during five regeneration cycles. Additionally, MP1HCMW efficiently removed Cr(VI) via pore filling, electrostatic attraction, ion exchange, reduction, complexation, and precipitation. Summarily, Fe/N co-doped porous hydrochar was a feasible adsorbent with outstanding remediation potential for Cr(VI)-contaminated water.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Adsorción , Porosidad , Contaminantes Químicos del Agua/química , Concentración de Iones de Hidrógeno , Cromo/química , Cinética , Fenómenos Magnéticos
16.
ACS Nano ; 18(18): 11933-11940, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38663413

RESUMEN

In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.

17.
Nat Commun ; 14(1): 7708, 2023 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-38001072

RESUMEN

Seawater electrolysis is a viable method for producing hydrogen on a large scale and low-cost. However, the catalyst activity during the seawater splitting process will dramatically degrade as salt concentrations increasing. Herein, CoP is discovered that could reject chloride ions far from catalyst in electrolyte based on molecular dynamic simulation. Thus, a binder-free electrode is designed and constructed by in-situ growth of homogeneous CoP on rGO nanosheets wrapped around the surface of Ti fiber felt for seawater splitting. As expected, the as-obtained CoP/rGO@Ti electrode exhibits good catalytic activity and stability in alkaline electrolyte. Especially, benefitting from the highly effective repulsive Cl- intrinsic characteristic of CoP, the catalyst maintains good catalytic performance with saturated salt concentration, and the overpotential increasing is less than 28 mV at 10 mA cm-2 from 0 M to saturated NaCl in electrolyte. Furthermore, the catalyst for seawater splitting performs superior corrosion-resistance with a low solubility of 0.04%. This work sheds fresh light into the development of efficient HER catalysts for salinity tolerance hydrogen evolution.

18.
ACS Nano ; 17(5): 4387-4395, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36802507

RESUMEN

Ullmann-like on-surface synthesis is one of the most appropriate approaches for the bottom-up fabrication of covalent organic nanostructures and many successes have been achieved. The Ullmann reaction requires the oxidative addition of a catalyst (a metal atom in most cases): the metal atom will insert into a carbon-halogen bond, forming organometallic intermediates, which are then reductively eliminated and form C-C covalent bonds. As a result, traditional Ullmann coupling involves reactions of multiple steps, making it difficult to control the final product. Moreover, forming the organometallic intermediates will potentially poison the metal surface catalytic reactivity. In the study, we used the 2D hBN, an atomically thin sp2-hybridized sheet with a large band gap, to protect the Rh(111) metal surface. It is an ideal 2D platform to decouple the molecular precursor from the Rh(111) surface while maintaining the reactivity of Rh(111). We realize an Ullmann-like coupling of a planar biphenylene-based molecule, i.e., 1,8-dibromobiphenylene (BPBr2), on an hBN/Rh(111) surface with an ultrahigh selectivity of the biphenylene dimer product, containing 4-, 6-, and 8-membered rings. The reaction mechanism, including electron wave penetration and the template effect of the hBN, is elucidated by combining low-temperature scanning tunneling microscopy and density functional theory calculations. Our findings are expected to play an essential role regarding the high-yield fabrication of functional nanostructures for future information devices.

19.
Angew Chem Int Ed Engl ; 51(34): 8644-7, 2012 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-22821752

RESUMEN

Asymmetric expansion: A catalytic asymmetric ring-expansion reaction of the title compounds occurs in the presence of a Sc(OTf)(3) catalyst bearing an N,N'-dioxide-based ligand. Highly functionalized 2-quinolone derivatives containing a chiral C4-quaternary stereocenter were obtained in high yields and high levels of selectivity under mild reaction conditions (see scheme; Tf=trifluoromethanesulfonyl).


Asunto(s)
Compuestos Azo/química , Ésteres/química , Isatina/química , Quinolinas/síntesis química , Catálisis , Estructura Molecular , Quinolinas/química , Escandio/química , Estereoisomerismo
20.
Front Cardiovasc Med ; 9: 835244, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35387435

RESUMEN

Diabetic cardiomyopathy (DCM) is a primary cause of death in diabetic patients; however, its molecular mechanism is not yet clear, and there is no uniform standard for diagnosis. The aim of this study is to discover the pathogenesis and potential therapeutic targets of DCM through screening and analysis of differentially expressed genes (DEGs) in heart ventricles of DCM, and to testify the role of key hub genes in DCM-induced myocardial dysfunction. Datasets GSE4745 and GSE6880 were downloaded from the GEO database. The difference analysis, visual analysis, cluster analysis and enrichment analysis were performed by using R language, python scripts and bioinformatics software followed by the construction of protein-protein interaction (PPI) network to obtain hub genes. The DCM models were established by streptozocin (STZ) injection to the male mice. The cardiac function and the expressions of hub genes were examined by using echocardiography and real-time quantitative poly-merase chain reaction (RT-qPCR), followed by multiple statistical analyses. Bioinformatic results indicate that mitochondrial dysfunction, disturbed lipid metabolism and decreased collagen synthesis are the main causes of the DCM development. In particular, the hub gene Cyp1a1 that encodes Cytochrome P450 1A1 (CYP4501A1) enzyme has the highest connectivity in the interaction network, and is associated with mitochondrial homeostasis and energy metabolism. It plays a critical role in the oxidation of endogenous or exogenous substrates. Our RT-qPCR results confirmed that ventricular Cyp1a1 mRNA level was nearly 12-fold upregulated in DCM model compared to normal control, which was correlated with abnormal cardiac function in diabetic individuals. CYP4501A1 protein expression in mitochondria was also increased in diabetic hearts. However, we found no significant changes in collagen expressions in cardiac ventricles of mice with DCM. This study provided compact data support for understanding the pathogenesis of DCM. CYP4501A1 might be considered as a potential candidate targeting for DCM therapy. Follow-up animal and clinical verifications need to be further explored.

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