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1.
J Org Chem ; 89(11): 7609-7617, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38787532

RESUMO

Activation and cleavage of C-C double bonds are long-standing challenges in synthetic chemistry. Herein, we report an unprecedented azide-mediated C-C double bond fragmentation of gem-difluoroalkenes under mild and metal-free conditions, enabling the efficient synthesis of structurally diverse aromatic nitriles in moderate to good yields. This protocol is also amenable to the cyanation of gem-dichloro and dibromo alkenes. This reaction features simple operation and good functional group compatibility and can be implemented at a gram scale.

2.
Org Lett ; 26(20): 4168-4172, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38727243

RESUMO

By using cyclic (vinyl triflate)iodonium salts, a novel triple Suzuki-Miyaura reaction was accomplished for the synthesis of polyaromatic ethylene derivatives in the presence of palladium catalysts. The reaction exhibits extensive compatibility with a wide range of readily available arylboronic acids, giving triaryl-substituted ethylenes in good yields.

3.
Beilstein J Org Chem ; 20: 841-851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655558

RESUMO

Cyclic annulation involving diaryliodonium salts is an efficient tool for the construction of two or more chemical bonds in a one-pot process. Ortho-functionalized diaryliodonium salts have showcased distinct reactivity in the exploration of benzocyclization or arylocyclization. With this strategy of ortho-ester-substituted diaryliodonium salts, herein, we utilized a copper catalyst to activate the C-I bond of diaryliodonium salts in the generation of aryl radicals, thus resulting in an annulation reaction with naphthols and substituted phenols. This approach yielded a diverse array of 3,4-benzocoumarin derivatives bearing various substituents.

4.
Phytother Res ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38666435

RESUMO

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/ß-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

5.
World J Cardiol ; 16(2): 92-97, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38456070

RESUMO

BACKGROUND: Spontaneous coronary artery rupture (SCAR) is a rare and life-threatening complication after lung cancer surgery. We present a case of SCAR following left upper lobectomy, successfully managed through emergency thoracotomy and coronary artery ligation. CASE SUMMARY: A 61-year-old male patient underwent left upper lobectomy and mediastinal lymph node dissection for lung cancer. The surgery was performed using single-port video-assisted thoracoscopic surgery, and there were no observed complications during the procedure. However, 19 h after surgery, the patient experienced chest discomfort and subsequently developed severe symptoms, including nausea, vomiting, and a drop in blood pressure. Urgent measures were taken, leading to the diagnosis of SCAR. The patient underwent emergency thoracotomy and coronary artery ligation, successfully stopping the bleeding and stabilizing the condition. Despite postoperative complications, the patient made a successful recovery and was discharged from the hospital. CONCLUSION: SCAR is a rare but life-threatening complication following lung cancer surgery. Immediate thoracotomy has been shown to be a life-saving measure, while stenting is not the preferred initial approach.

6.
Org Biomol Chem ; 22(3): 486-490, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38111368

RESUMO

In contrast to the previously reported intramolecular aryl migration, we present the selective sulfenylation of ortho-trifluoromethanesulfonate (OTf) substituted diaryliodonium salts with thiols. As such, diarylsulfides bearing vicinal OTf groups were synthesized in good yields. The unique reactivity of the vicinal OTf group and the sulfur atom in arylsulfides offers further transformations.

7.
J Org Chem ; 88(18): 13089-13101, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37661693

RESUMO

In this study, we present an efficient site-selective O-arylation method applicable to a broad range of complex arenes involving intramolecular aryl rearrangement. The reaction was facilitated by diaryliodonium salts bearing vicinal trifluoromethanesulfonate (OTf) groups. The procedure was initiated with selective C-H bond activation of arenes, which were then converted into diaryl ethers through nucleophilic aromatic substitution (SNAr). This synthetic method successfully affords complex diaryl ether derivatives, showcasing its practicality for the diversification of functionalized arenes and pharmaceutical agents.

8.
Chem Biol Drug Des ; 102(4): 749-762, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37341065

RESUMO

The study aimed to assess the role of hsa-miR-503-5p in cisplatin resistance and angiogenesis in LUAD and its underlying mechanisms. Hsa-miR-503-5p expression in LUAD and the target gene downstream of hsa-miR-503-5p was predicted by bioinformatics analysis. Binding relationship between the two genes was verified by dual-luciferase reporter assay. qRT-PCR was conducted for detecting gene expression in cells, CCK-8 for IC50 value, angiogenesis assay for human umbilical vein endothelial cell (HUVEC) angiogenic ability, flow cytometry for apoptosis ability, transwell assay for migration ability, and western blot for detecting the protein expression of vascular endothelial growth factor receptor 1 (VEGFR1), VEGFR2, and CTD small phosphatase like (CTDSPL). The results showed that hsa-miR-503-5p showed high expression, while its target gene CTDSPL presented decreased expression in LUAD. Hsa-miR-503-5p also had high expression in cisplatin-resistant LUAD cells. Knockdown of hsa-miR-503-5p resensitized LUAD cells to cisplatin, inhibited angiogenesis of drug-resistant cells, and reduced the protein expression of VEGFR1, VEGFR2, and EMT-related targets in cisplatin-resistant LUAD cells, but promoted the apoptosis ability. Hsa-miR-503-5p bound to CTDSPL gene and promoted cisplatin resistance and malignant progression of LUAD cells by negatively regulating CTDSPL. Our results revealed that hsa-miR-503-5p and CTDSPL may be novel targets for overcoming cisplatin resistance in LUAD.


Assuntos
Adenocarcinoma de Pulmão , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares , MicroRNAs , Humanos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Linhagem Celular Tumoral , Proliferação de Células , Cisplatino/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MicroRNAs/genética , Fator A de Crescimento do Endotélio Vascular , Resistencia a Medicamentos Antineoplásicos/genética
9.
Sci Rep ; 13(1): 9932, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337051

RESUMO

Free-falling cubic Test Masses (TMs) are a key component of the interferometer used for low-frequency gravitational wave (GW) detection in space. However, exposure to energetic particles in the environment can lead to electrostatic charging of the TM, resulting in additional electrostatic and Lorentz forces that can impact GW detection sensitivity. To evaluate this effect, the high-energy proton data set of the Geostationary Operational Environmental Satellite (GOES) program was used to analyze TM charging due to Solar Proton Events (SPEs) in the 24th solar cycle. Using the Geant4 Monte Carlo toolkit, the TM charging process is simulated in a space environment for SPEs falling into three ranges of proton flux: (1) greater than 10 pfu and less than 100 pfu, (2) greater than 100 pfu and less than 1000 pfu, and (3) greater than 1000 pfu. It is found that SPEs charging can reach the threshold within 535 s to 18.6 h, considering a reasonable discharge threshold of LISA and Taiji. We demonstrate that while there is a somewhat linear correlation between the net charging rate of the TM and the integrated flux of [Formula: see text] 10 MeV SPEs, there are many cases in which the integrated flux is significantly different from the charging rate. Therefore, we investigate the difference between the integral flux and the charging rate of SPEs using the charging efficiency assessment method. Our results indicate that the energy spectrum structure of SPEs is the most important factor influencing the charging rate. Lastly, we evaluate the charging probability of SPEs in the 24th solar cycle and find that the frequency and charging risk of SPEs are highest in the 3rd, 4th, 5th, 6th, and 7th years, which can serve as a reference for future GW detection spacecraft.

10.
Chem Rec ; 23(10): e202300138, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37249418

RESUMO

Our research interest focusing on synthetic methodology with diaryliodonium salts, is summarized in this account. Besides employing a dual activation strategy of C-I and ortho C-H bonds, we have introduced vicinal functional groups at ortho-positions of diaryliodonium salts, in which their unique reactivities have been explored in various processes, including arylation, diarylation, cascade annulation, benzocyclization, arylocyclization, and intramolecular aryl migration. The variety of mechanisms of these reactions that involves either transition metals, especially palladium in organometallic catalysis, or transition-metal free conditions, were discussed in the context.

11.
Angew Chem Int Ed Engl ; 62(28): e202304897, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37195599

RESUMO

The Truce-Smiles rearrangement is an intramolecular SN Ar reaction, enabling the formation of a new arene carbon-carbon bond with sufficiently strong carbon-centered nucleophile. Reported here are ortho-tosylmethylene functionalized diaryliodonium salts, which can undergo an unprecedented Truce-Smiles rearrangement in ionic liquids, resulting in sulfonyl-substituted ortho-iodo diarylmethanes as a powerful class of building blocks in chemical synthesis. The protocol features aryliodo moiety as a hyper nucleofuge, facilitating the formation of Meisenheimer complex within the migratory system.

12.
Poult Sci ; 102(6): 102646, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37031585

RESUMO

Adipose tissue (AT) is considered as a regional immune organ and plays an important role in the anti-infection immune response. However, the function and mechanism of chicken AT in response to secondary immune response remain poorly understood. Here, we used mRNA and microRNA (miRNA) sequencing technology to survey the transcriptomic landscape of chicken abdominal adipose tissue (AAT) during the first and second immunization with Newcastle disease virus (NDV) vaccine, and carried out bioinformatics analysis, such as Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment analysis, protein-protein interaction (PPI) analysis, and miRNA-mRNA integrated analysis. The results indicated that chicken AAT actively responded to the secondary immune response. DNA replication and cytoskeleton regulation as the regulatory functions of immune activation changed significantly, and weakened lipid metabolism was an effective strategy for the secondary immunity. Mechanically, the regulatory network between the differentially expressed miRNAs (DEMs) and their targeted differentially expressed genes (DEGs), such as miR-206/miR-499-5p-nuclear receptor subfamily 4 group A member 3 (NR4A3)/methylsterol monooxygenase 1 (MSMO1) pathway, was one of the potential key mechanisms by which AAT responded to the secondary immune response. In conclusion, regional immunity of chicken AT responds to secondary immunity by promoting immune activation and weakening lipid metabolism, and this study can instruct future research on antiviral strategy.


Assuntos
MicroRNAs , Doença de Newcastle , Vacinas , Animais , Galinhas/genética , Doença de Newcastle/prevenção & controle , Metabolismo dos Lipídeos , MicroRNAs/genética , MicroRNAs/metabolismo , Perfilação da Expressão Gênica/métodos , Perfilação da Expressão Gênica/veterinária , RNA Mensageiro/genética
13.
Vet Microbiol ; 281: 109746, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37075663

RESUMO

At present, stress-induced immunosuppression is still a hidden threat that leads to immunization failure and outbreaks of poultry diseases, and causes huge economic losses to the modern poultry industry. However, the molecular mechanisms of stress-induced immunosuppression affecting viral vaccine immunity are still poorly understood. Here, we identified circAKIRIN2 as a conserved circular transcript in chicken, and explored its expression patterns in different immune states by quantitative real-time PCR (qRT-PCR), then conducted bioinformatics analysis. The results showed that circAKIRIN2 actively participated in the process of stress-induced immunosuppression affecting the immune response to infectious bursal disease virus (IBDV) vaccine. The key time points for circAKIRIN2 involving in the process were 2 day post immunization (dpi), 5 dpi, and 28 dpi, especially at the acquired immune stage. The important tissues that responded to the process included the heart, liver, and lung, all of which changed significantly. In addition, circAKIRIN2 as a competing endogenous RNA (ceRNA) sponging zinc finger and BTB domain containing 20 (ZBTB20) was a potential molecular mechanism for regulating immune functions in the process. In conclusion, circAKIRIN2 is a key regulatory factor for stress-induced immunosuppression affecting the IBDV vaccine immune response, and this study can provide a new perspective for exploring the molecular regulatory mechanisms of stress-induced immunosuppression affecting immune response.


Assuntos
Infecções por Birnaviridae , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Vacinas Virais , Animais , Galinhas , Vírus da Doença Infecciosa da Bursa/genética , RNA Circular , Terapia de Imunossupressão/veterinária , Imunidade , Infecções por Birnaviridae/prevenção & controle , Infecções por Birnaviridae/veterinária
14.
PeerJ ; 11: e14529, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36874964

RESUMO

MiR-155 and CTLA-4 are important factors involved in the regulation of immune function. However, there is no report about their involvement in function regulation of stress-induced immunosuppression affecting immune response. In this study, the chicken model of stress-induced immunosuppression affecting immune response (simulation with dexamethasone and immunization with Newcastle disease virus (NDV) attenuated vaccine) was established, then the expression characteristics of miR-155 and CTLA-4 gene were analyzed at several key time points during the processes of stress-induced immunosuppression affecting NDV vaccine immune response at serum and tissue levels. The results showed that miR-155 and CTLA-4 were the key factors involved in stress-induced immunosuppression and NDV immune response, whose functions involved in the regulation of immune function were different in different tissues and time points, and 2 day post immunization (dpi), 5dpi and 21dpi were the possible key regulatory time points. CTLA-4, the target gene of miR-155, had significant game regulation relationships between them in various tissues, such as bursa of Fabricius, thymus and liver, indicating that miR-155-CTLA-4 pathway was one of the main mechanisms of their involvement in the regulations of stress-induced immunosuppression affecting NDV immune response. This study can lay the foundation for in-depth exploration of miR-155-CTLA-4 pathway involved in the regulation of immune function.


Assuntos
Galinhas , MicroRNAs , Animais , Vírus da Doença de Newcastle , Antígeno CTLA-4 , Terapia de Imunossupressão , Vacinas Atenuadas , Imunidade
15.
Small ; 19(1): e2204537, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366937

RESUMO

Carbon nanotube (CNT) field-effect transistors (FETs) have been considered ideal building blocks for radiation-hard integrated circuits (ICs), the demand for which is exponentially growing, especially in outer space exploration and the nuclear industry. Many studies on the radiation tolerance of CNT-based electronics have focused on the total ionizing dose (TID) effect, while few works have considered the single event effects (SEEs) and displacement damage (DD) effect, which are more difficult to measure but may be more important in practical applications. Measurements of the SEEs and DD effect of CNT FETs and ICs are first executed and then presented a comprehensive radiation effect analysis of CNT electronics. The CNT ICs without special irradiation reinforcement technology exhibit a comprehensive radiation tolerance, including a 1 × 104 MeVcm2 mg-1 level of the laser-equivalent threshold linear energy transfer (LET) for SEEs, 2.8 × 1013 MeV g-1 for DD and 2 Mrad (Si) for TID, which are at least four times higher than those in conventional radiation-hardened ICs. The ultrahigh intrinsic comprehensive radiation tolerance will promote the applications of CNT ICs in high-energy solar and cosmic radiation environments.


Assuntos
Nanotubos de Carbono , Transistores Eletrônicos , Tolerância a Radiação
16.
Org Biomol Chem ; 20(44): 8628-8632, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36314988

RESUMO

We herein report an efficient regioselective cascade of arylation and cyclization of arylcarboxylic acids via Pd(II)-activation of both C-I and vicinal C-NO2 bonds of ortho-nitro-substituted diaryliodonium salts.


Assuntos
Sais , Ciclização , Sais/química , Catálise
17.
Front Chem ; 10: 1008332, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36176892

RESUMO

A novel single-atom catalyst of Fe adsorbed on χ3-borophene has been proposed as a potential catalyst for CO oxidation reaction (COOR). Quantitative pictures have been provided of both the stability of Fe@χ3-borophene and various kinetic reaction pathways using first-principles calculations. Strong adsorption energy of -3.19 eV and large diffusion potential of 3.51 eV indicates that Fe@χ3-borophene is highly stable. By exploring reaction mechanisms for COOR, both Eley-Ridel (E-R) and trimolecule E-R (TER) were identified as possible reaction paths. Low reaction barriers with 0.49 eV of E-R and 0.57 eV of TER suggest that Fe@χ3-borophene is a very promising catalyst for COOR. Charge transfer between the χ3-borophene and CO, O2 and CO2 gas molecules plays a key role in lowering the energy barrier during the reactions. Our results propose that Fe@χ3-borophene can be a good candidate of single-atom catalyst for COOR with both high stability and catalytic activity.

18.
Animals (Basel) ; 12(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36139236

RESUMO

Studies have shown that circulating microRNAs (miRNAs) are important players in the immune response and stress-induced immunosuppression. However, the function and mechanism of stress-induced immunosuppression affecting the immune response to the Newcastle disease virus (NDV) vaccine remain largely unknown. This study analyzed the changes of 15 NDV-related circulating miRNAs at different immune stages by qRT-PCR, aiming to explore the key timepoints, potential biomarkers, and mechanisms for the functional regulation of candidate circulating miRNAs under immunosuppressed conditions. The results showed that stress-induced immunosuppression induced differential expressions of the candidate circulating miRNAs, especially at 2 days post immunization (dpi), 14 dpi, and 28 dpi. In addition, stress-induced immunosuppression significantly affected the immune response to NDV vaccine, which was manifested by significant changes in candidate circulating miRNAs at 2 dpi, 5 dpi, and 21 dpi. The featured expressions of candidate circulating miRNAs indicated their potential application as biomarkers in immunity and immunosuppression. Bioinformatics analysis revealed that the candidate circulating miRNAs possibly regulated immune function through key targeted genes, such as Mg2+/Mn2+-dependent 1A (PPM1A) and Nemo-like kinase (NLK), in the MAPK signaling pathway. This study provides a theoretical reference for studying the function and mechanism of circulating miRNAs in immune regulation.

20.
Vet Microbiol ; 273: 109546, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35994844

RESUMO

Stress-induced immunosuppression is one of the most common hazards in poultry intensive production, which often leads to vaccination failure and severe economic losses. At present, there is no report about the function and mechanism of circulating miRNA on stress-induced immunosuppression affecting immune response. In this study, the changes of circulating miR-20a-5p under stress-induced immunosuppressive condition were analyzed by qRT-PCR, and the key time points, tissues and mechanisms for functional regulation of miR-20a-5p in the process of stress-induced immunosuppression affecting avian influenza virus (AIV) vaccine immune response were identified. The results showed that stress-induced immunosuppression down-regulated miR-20a-5p and further affected AIV vaccine immune response, in which 5 day post immunization (dpi) was a key time point, and the heart, lung, and proventriculus were the important tissues. The game relationship analysis between miR-20a-5p and its target nuclear receptor subfamily 4 group A member 3 (NR4A3) gene showed that "miR-20a-5p/NR4A3" pathway was the potential key mechanism of this process, especially for heart and lung. This study provides insights into the molecular mechanisms of stress-induced immunosuppression affecting immune response.


Assuntos
Vacinas contra Influenza , Influenza Aviária , MicroRNAs , Animais , Galinhas/genética , Imunidade , Terapia de Imunossupressão/veterinária , Influenza Aviária/prevenção & controle , MicroRNAs/genética , MicroRNAs/metabolismo
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