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1.
Mol Cell Biochem ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38376663

RESUMO

Atherosclerosis (AS) is a pivotal pathological basis of cardiovascular and cerebrovascular diseases, and circular RNAs (circRNAs) has been disclosed to exert a vital part in the progression of AS. However, the functions of circ_0004872 in the progression of AS is indistinct. In this context, we aimed to elucidate the role of circ_0004872 and the potential mechanism in AS. The level of circ_0004872, miR-424-5p and fibroblast growth factor receptor substrate 2 (FRS2) was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was monitored by Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine (EDU) assays. The invasion and migration capabilities of VSMCs were tested by transwell assays and wound-healing assay, respectively. Western blot was adopted to check the protein levels of CyclinD1, Vimentin and FRS2. Dual-luciferase reporter and RNA immunoprecipitation assay were executed to manifest the interaction between miR-424-5p and circ_0004872 or FRS2. The level of circ_0004872 was increased in the serum samples of AS patients and ox-LDL-exposed VSMCs. Ox-LDL exposure triggered cell proliferation, invasion and migration ability of VSMCs. depletion of circ_0004872 partly weakened ox-LDL-mediated effects in VSMCs. Mechanistically, circ_0004872 functioned as a sponge of miR-424-5p, and miR-424-5p inhibition partly alleviated circ_0004872 deficiency-mediated influences in VSMCs. Additionally, miR-424-5p interacted with FRS2, and miR-424-5p constrained dysfunction in ox-LDL-stimulated VSMCs via reducing FRS2 level. Notably, circ_0004872 functioned as a sponge of miR-424-5p to elevate FRS2 expression. Circ_0004872 accelerated ox-LDL-induced damage via mediating miR-424-5p/FRS2 axis.

2.
J Org Chem ; 89(8): 5434-5441, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38581391

RESUMO

A mild method for the C-H/S-H coupling of pyrazol-5-amines and thiophenols was developed via electrochemistry, giving diverse amino pyrazole thioether derivatives in 37-98% yields. This electrochemical reaction is sustainable and an atom-efficient approach with good functional group tolerance and scalability by avoiding metal and external chemical oxidants.

3.
J Org Chem ; 89(9): 6395-6404, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38621116

RESUMO

We developed an electrochemical approach for benzylic C(sp3)-H imidation by virtue of the in situ generated oxygen-centered radicals (OCRs). The electrochemical imidation provides a complementary approach to giving distinct imide products compared with previous acyloxylation products. This protocol exhibits good site selectivity and broad substrate generality. Moreover, the utility of the OCR-mediated protocol was extended to the electrochemical oxidation of silane, and its robustness was also highlighted by the imidation of complex substrates, which would otherwise be inaccessible for previous approaches. A plausible reaction mechanism was proposed to rationalize the experimental observations.

4.
J Org Chem ; 89(9): 6106-6116, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38632856

RESUMO

An electrochemical oxidative cross-coupling strategy for the synthesis of N-sulfenylsulfoximines from sulfoximines and thiols was accomplished, giving diverse N-sulfenylsulfoximines in moderate to good yields. Moreover, this strategy can be extended to construct the N-P bond of N-phosphinylated sulfoximines. With electrons as reagents, the oxidative dehydrogenation cross-coupling reaction proceeds smoothly in the absence of traditional redox reagents.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38904634

RESUMO

Objective: This study aims to analyze the application effect of IMB (Information-Motivation-Behavioral skills) model rehabilitation nursing, which focuses on enhancing patient knowledge, motivation, and skills for disease management in patients with diabetes and end-stage renal disease receiving maintenance hemodialysis and its impact on the patient's nutritional status. Methods: Eighty-four patients with diabetes and end-stage renal disease undergoing maintenance hemodialysis were selected as study subjects at our hospital. All patients met the inclusion criteria and were divided into two groups based on the nursing interventions received. The control group (n=42) received routine rehabilitation nursing intervention, while the observation group (n=42) received IMB-guided rehabilitation nursing intervention. The effects of nursing intervention, psychological conditions, nutritional status, and quality of life were evaluated using standardized measurement tools. Psychological conditions were assessed using the Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS). Nutritional status was evaluated through measurements of albumin (ALB), body composition analysis (BBC), hemoglobin (Hb), triceps skinfold thickness (TSF), arm circumference (A.C.), and arm muscle circumference (AMC). Quality of life was assessed using the SF-36 Health Survey. Comparative analysis was conducted to examine the differences between the two groups in terms of the aforementioned outcomes. Results: The results of the study revealed compelling data showcasing the effectiveness of the nursing intervention. Notably, after the nursing intervention, ALB (albumin) levels in the observation group increased by 12%, indicating a significant improvement in nutritional status. This increase signifies enhanced protein synthesis and improved overall metabolic functioning among the patients. Additionally, the SF-36 scores, reflecting the quality of life, demonstrated a substantial improvement of 15 points in the observation group following the nursing intervention. This improvement indicates a significant enhancement in various aspects of health-related quality of life, such as physical functioning, mental health, social functioning, and overall well-being. Furthermore, the total nursing effective rate in the observation group was an impressive 97.62%, surpassing the 80.95% rate in the control group. This statistically significant difference (P < .05) emphasizes the superior outcomes achieved through the nursing intervention in the observation group. Moreover, when comparing psychological conditions, the SAS scores in the observation group after the nursing intervention were significantly lower than those in the control group by 8 points (P < .05). Similarly, the SDS scores in the observation group showed a significant decrease of 10 points compared to the control group (P < .05). These findings indicate a substantial reduction in anxiety and depression levels among patients in the observation group. Conclusion: The findings of this study have significant implications for patient care and highlight potential areas for future research. The results suggest that integrating IMB-guided approaches into hemodialysis care protocols could significantly enhance patient well-being. The notable improvements in nutritional status, as indicated by the increase in ALB levels, and the substantial enhancement in quality of life, as reflected by the improvement in SF-36 scores, underscore the effectiveness of the nursing intervention. These findings have important implications for clinical practice, emphasizing the need for broader implementation of IMB-guided approaches in diverse clinical settings. By incorporating these interventions into routine hemodialysis care, healthcare providers can potentially improve patient outcomes and enhance their overall quality of life. Furthermore, these results also highlight potential areas for future research. Additional studies could explore the long-term effects of the nursing intervention on patient health outcomes, sustainability of the improvements observed, and the cost-effectiveness of implementing IMB-guided approaches in hemodialysis settings. Moreover, investigating the feasibility and efficacy of these interventions in different patient populations could further expand our understanding and inform tailored approaches for specific subgroups.

6.
Chem Biodivers ; 21(4): e202301899, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38345198

RESUMO

This study presents the fabrication of a novel porous composite of graphene oxide-montmorillonite (GO-MMT) through the modification of montmorillonite using the freeze-drying method for the purpose of Pb removal. The characterization of the GO-MMT composite was conducted using scanning electron microscopy, Fourier transform infrared spectrometry, and X-ray diffraction. The results from batch adsorption experiments revealed that the GO-MMT composite exhibited a superior capacity for Pb removal compared to MMT. Furthermore, a single factor experiment confirmed that the dosage of the GO-MMT composite or GO, pH, temperature, and reaction time all significantly influenced the adsorption of Pb by the GO-MMT composite, MMT, or GO. This superiority can be attributed to the presence of oxygen-containing functional groups, the site-blocking effect, and the ion exchange mechanism exhibited by the GO-MMT composite.


Assuntos
Grafite , Poluentes Químicos da Água , Bentonita/química , Chumbo , Adsorção , Grafite/química , Poluentes Químicos da Água/química
7.
J Org Chem ; 88(17): 12502-12518, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37579226

RESUMO

A copper-catalyzed aerobic oxidative/decarboxylative phosphorylation of aryl acrylic acids with P(III)-nucleophiles via the Michaelis-Arbuzov rearrangement for the synthesis of ß-ketophosphine oxides, ß-ketophosphinates, and ß-ketophosphonates is reported. The present reaction could be conducted effectively without the use of a ligand and a base. Various kinds of aryl acrylic acids and P(III)-nucleophiles are tolerated in the transformation, generating the desired ß-keto-organophosphorus compounds as a valuable class of phosphorus-containing intermediates with good to excellent yields. In addition, the possible mechanism and kinetic studies for the reaction have been explored by step-by-step control experiments and competitive experiments, and the results proved that this transformation may follow second-order chemical kinetics as well as involve a radical process.

8.
J Org Chem ; 88(23): 16196-16215, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37955519

RESUMO

A simple and efficient method for the ruthenium-catalyzed 1,6-hydroalkylation of para-quinone methides (p-QMs) with ketones via the in situ activation of C(sp3)-H bonds has been disclosed. Without the need for preactivation of the substrates and oxidant, a broad range of p-QMs and ketones are well tolerated, producing the expected 1,6-hydroalkylation products with moderate to good yields. Step-by-step control experiments and DFT calculation were conducted systematically to gain insights for the plausible reaction mechanism. This finding may have potential application in the selective diarylmethylation of ketones at the α-C position in organic synthesis.

9.
Chem Rev ; 121(14): 9039-9112, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32786423

RESUMO

Catalytic transformations involving metal carbenes are considered one of the most important aspects of homogeneous transition metal catalysis. Recently, gold-catalyzed generation of gold carbenes from readily available alkynes represents a significant advance in metal carbene chemistry. This Review summarizes the advances in the gold-catalyzed nitrene-transfer reactions of alkynes with nitrogen-transfer reagents, such as azides, nitrogen ylides, isoxazoles, and anthranils, and gold-catalyzed carbene-transfer reactions, involving oxygen atom-transfer reactions of alkynes with nitro compounds, nitrones, sulfoxides, and pyridine N-oxides, through the presumable α-imino gold carbene and α-oxo gold carbene intermediates, respectively. Gold-catalyzed processes are reviewed by highlighting their product diversity, selectivity, and applicability, and the mechanistic rationale is presented where possible.

10.
Sensors (Basel) ; 23(14)2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37514796

RESUMO

The development and utilization of urban underground space is an important way to solve the "great urban disease". As one of the most important types of urban underground foundations, utility tunnels have become increasingly popular in municipal construction. The investigation of utility tunnels is a general task and three-dimensional laser scanning technology has played a significant role in surveying and data acquisition. However, three-dimensional laser scanning technology suffers from noise and occlusion in narrow congested utility tunnel spaces, and the acquired point clouds are imperfect; hence, errors and redundancies are introduced in the extracted geometric elements. The topology of reconstructed BIM objects cannot be ensured. Therefore, in this study, a hierarchical segmentation method for point clouds and a topology reconstruction method for building information model (BIM) objects in utility tunnels are proposed. The point cloud is segmented into facades, planes, and pipelines hierarchically. An improved mean-shift algorithm is proposed to extract wall line features and a local symmetry-based medial axis extraction algorithm is proposed to extract pipelines from point clouds. A topology reconstruction method that searches for the neighbor information of wall and pipeline centerlines and establishes collinear, perpendicular, and intersecting situations is used to reconstruct a topologically consistent 3D model of a utility tunnel. An experiment on the Guangzhou's Nansha District dataset successfully reconstructed 24 BIM wall objects and 12 pipelines within the utility tunnel, verifying the efficiency of the method.

11.
Angew Chem Int Ed Engl ; 62(8): e202215616, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36573021

RESUMO

Herein, an I2 -catalyzed unprecedented cycloisomerization of ynamides is developed, furnishing various functionalized bis(indole) derivatives in generally good to excellent yields with wide substrate scope and excellent atom-economy. This protocol not only represents the first molecular-iodine-catalyzed tandem complex alkyne cycloisomerizations, but also constitutes the first chemoselective cycloisomerization of tryptamine-ynamides involving distinctively different C(sp3 )-C(sp3 ) bond cleavage and rearrangement. Moreover, chiral tetrahydropyridine frameworks containing two stereocenters are obtained with moderate to excellent diastereoselectivities and excellent enantioselectivities. Meanwhile, cycloisomerization and aromatization of ynamides produce pyrrolyl indoles with high efficiency enabled by I2 . Additionally, control experiments and theoretical calculations reveal that this reaction probably undergoes a tandem 5-exo-dig cyclization/rearrangement process.

12.
J Am Chem Soc ; 144(15): 6981-6991, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35394289

RESUMO

Significant advances have been achieved for the construction of chiral skeletons containing 1,2,3-triazoles via transition-metal-catalyzed asymmetric azide-alkyne cycloaddition; however, most of them have been limited to terminal alkynes in the synthesis of central chirality via desymmetrization and dynamic/dynamic kinetic resolution. Enantioselective transition-metal-catalyzed azide-internal-alkyne cycloaddition is extremely limited. Moreover, the construction of a challenging five-membered (hetero)biaryl axially chiral molecule via transition-metal-catalyzed asymmetric azide-internal-alkyne cycloaddition is still underexplored. Herein, we first report an atroposelective and atom-economical synthesis of axially chiral 1,4,5-trisubstituted 1,2,3-triazoles, directly acting as core chiral units of challenging five-membered atropisomers, via the enantioselective Rh-catalyzed azide-alkyne cycloaddition (E-RhAAC) of internal alkynes and azides. The reaction demonstrates excellent functional group tolerance, forging a variety of C-C axially chiral 1,2,3-triazoles under mild conditions with moderate to excellent yields (up to 99% yield) and generally high to excellent enantioselectivities (up to 99% ee) along with specific regiocontrol. The origin of regio- and enantioselectivity control is disclosed by density functional theory (DFT) calculations, providing new guidance for the facile construction of axially chiral compounds.


Assuntos
Azidas , Ródio , Alcinos , Catálise , Reação de Cicloadição , Estereoisomerismo , Triazóis
13.
J Org Chem ; 87(14): 9242-9249, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35795996

RESUMO

A facile method for the synthesis of bis-pyrazolo[3,4-b:4',3'-e]pyridines from easily available aromatic aldehydes and pyrazol-5-amines was developed via electrochemistry. The reaction proceeded smoothly under metal and external chemical oxidant-free conditions, giving a variety of bis-pyrazolo[3,4-b:4',3'-e]pyridines in moderate yields.

14.
Nanotechnology ; 34(10)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36562516

RESUMO

Transparent conductive films with high stability were prepared by embedding silver nanowires in colorless polyimide and adding a protective layer of exfoliated graphene. The films exhibit great light transmission and conductivity with a sheet resistance of 22 Ω sq-1at transmittance of 83%. Due to its special embedded structure, the conductive layer can withstand several peeling experiments without falling off. In addition, the most outstanding advantage is the ultra-high stability of the films, including high mechanical robustness, strong chemical corrosion resistance and high operating voltage capacity. The organic light-emitting diode devices prepared based on this transparent conductive electrode exhibit comparable efficiency to indium tin oxide (ITO) based devices, withC.E.max= 2.78 cd A-1,P-1.E.max= 1.89 lm W-1,EQEmax= 0.89%. Moreover, the efficiencies were even higher than that of ITO devices when the operating voltage of the device exceeds 5 V. The above performances show that the transparent conductive electrode based on this structure has high potential for application in organic electronic devices.

15.
J Org Chem ; 86(22): 16008-16015, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34260858

RESUMO

A facile and direct electrocatalytic C-C bond cleavage/functionalization reaction of isatins was developed. With isatins as the amino-attached C1 sources, a variety of aminobenzoates, and aminobenzamides were synthesized in moderate to good yields under mild conditions.


Assuntos
Isatina , ortoaminobenzoatos
16.
BMC Pulm Med ; 21(1): 277, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34454450

RESUMO

BACKGROUND: LncRNA DLGAP1-AS2 plays an oncogenic role in glioma, while its role in other cancers is unknown. This study aimed to study the role of DLGAP1-AS2 in non-small cell lung cancer (NSCLC). METHODS: Expression of DLGAP1-AS2 in NSCLC and paired non-tumor tissues from 64 NSCLC patients and the prognostic value of DLGAP1-AS2 for NSCLC were analyzed by performing a 5-year follow-up study. The interaction between DLGAP1-AS2 and miR-503 was confirmed by dual luciferase reporter assay, and their relationship was explored in NSCLC cells transfected with DLGAP1-AS2 expression vector or miR-503 mimic. The roles of DLGAP1-AS2 and miR-503 in regulating cyclin D1 expression were analyzed by RT-qPCR and Western blot. Cell proliferation was analyzed by CCK-8 assay. RESULTS: DLGAP1-AS2 was upregulated in NSCLC and predicted poor survival. Interaction between DLGAP1-AS2 and miR-503 was confirmed by dual luciferase activity assay. Overexpression experiments showed that DLGAP1-AS2 and miR-503 overexpression failed to significantly affect the expression of each other. Interestingly, DLGAP1-AS2 overexpression upregulated cyclin D1, a target of miR-503, increased cell proliferation and reduced the effects of miR-503 overexpression on cyclin D1 expression and cell proliferation. CONCLUSIONS: DLGAP1-AS2 may regulate miR-503/cyclin D1 to promote cell proliferation in NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Ciclina D1/metabolismo , Neoplasias Pulmonares/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/genética , Proteínas Associadas SAP90-PSD95/metabolismo , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Ciclina D1/genética , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , Proteínas Associadas SAP90-PSD95/genética
17.
Chem Soc Rev ; 49(24): 8897-8909, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33135691

RESUMO

Over the past two decades, the development and application of ynamide chemistry have received more and more attention. Ynamides have proven to be versatile reagents for organic synthesis, and have been widely applied to the rapid assembly of a diverse range of structurally complex N-containing molecules, especially the valuable N-heterocycles. In comparison with the well-established transition metal-catalyzed reactions of ynamides, metal-free ynamide transformations have relatively seldom been exploited. Recently, Brønsted acid-mediated reactions of ynamides represent significant advances in ynamide chemistry. This review summarizes the latest trends and developments of Brønsted acid-mediated reactions of ynamides, including cycloaddition, cyclization, intramolecular alkoxylation-initiated rearrangement, oxygen atom transfer reactions and hydro-heteroatom addition reactions.

18.
Nano Lett ; 20(11): 8267-8272, 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33135901

RESUMO

We report a new method to determine the orientation of individual nitrogen-vacancy (NV) centers in a bulk diamond and use them to realize a calibration-free vector magnetometer with nanoscale resolution. Optical vortex beam is used for optical excitation and scanning the NV center in a [111]-oriented diamond. The scanning fluorescence patterns of NV center with different orientations are completely different. Thus, the orientation information on each NV center in the lattice can be known directly without any calibration process. Further, we use three differently oriented NV centers to form a magnetometer and reconstruct the complete vector information on the magnetic field based on the optically detected magnetic resonance(ODMR) technique. Compared with previous schemes to realize vector magnetometry using an NV center, our method is much more efficient and is easily applied in other NV-based quantum sensing applications.

19.
Mol Ecol ; 29(19): 3762-3776, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32812678

RESUMO

Marine planktonic bacteria and archaea commonly exhibit pronounced seasonal succession in community composition. But the existence of seasonality in their assembly processes and between-domain differences in underlying mechanism are largely unassessed. Using a high-coverage sampling strategy (including single sample for each station during four cruises in different seasons), 16S rRNA gene sequencing, and null models, we investigated seasonal patterns in the processes governing spatial turnover of bacteria and archaea in surface coastal waters across a sampling grid over ~300 km in the East China Sea. We found that archaea only bloomed in prokaryotic communities during autumn and winter cruises. Seasonality mostly overwhelmed spatial variability in the compositions of both domains. Bacterial and archaeal communities were dominantly governed by deterministic and stochastic assembly processes, respectively, in autumn cruise, probably due to the differences in niche breadths (bacteria < archaea) and relative abundance (bacteria > archaea). Stochasticity dominated assembly mechanisms of both domains but was driven by distinct processes in winter cruise. Determinism-dominated assembly mechanisms of bacteria rebounded in spring and summer cruises, reflecting seasonal variability in bacterial community assembly. This could be attributed to seasonal changes in bacterial niche breadths and habitat heterogeneity across the study area. There were seasonal changes in environmental factors mediating the determinism-stochasticity balance of bacterial community assembly, holding a probability of the existence of unmeasured mediators. Our results suggest contrasting assembly mechanisms of bacteria and archaea in terms of determinism-vs.-stochasticity pattern and its seasonality, highlighting the importance of seasonal perspective on microbial community assembly in marine ecosystems.


Assuntos
Archaea , Bactérias , Archaea/genética , Bactérias/genética , China , Filogenia , RNA Ribossômico 16S/genética , Estações do Ano
20.
J Org Chem ; 85(20): 13029-13036, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-32954735

RESUMO

An intramolecular decarboxylative coupling reaction for the construction of 2-(1,3,4-oxadiazol-2-yl)aniline derivatives was developed from readily available isatins and hydrazides by virtue of electrochemistry. In this reaction, isatins were employed as amino-attached C1 sources, providing a variety of 2-(1,3,4-oxadiazol-2-yl)aniline derivatives with moderate to good yields.

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