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1.
J Comput Chem ; 45(14): 1087-1097, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243618

RESUMO

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

2.
J Org Chem ; 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38963688

RESUMO

We report herein an expedient method for the regioselective synthesis of indoles from o-haloanilines and α-ketol-derived N-tosylhydrazones. This two-step, modular synthesis of N-H indoles can be carried out conveniently without purification of intermediates.

3.
J Org Chem ; 89(9): 6230-6237, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38629386

RESUMO

A concise synthesis of pareitropone by oxidative cyclization of a phenolic nitronate is delineated. The use of TMSOTf as an additive to promote the facile formation of a strained norcaradiene intermediate provides convenient access to highly condensed multicyclic tropones in high yields. This synthesis is modular, efficient, and scalable, highlighting the synthetic utility of radical anion coupling reactions in annulation reactions. This work is discussed in the context of total syntheses of the tropoloisoquinoline alkaloids. Also included are the preparation of several congeners and a brief description of their biological activities.


Assuntos
Antineoplásicos , Humanos , Estrutura Molecular , Ciclização , Linhagem Celular Tumoral , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Oxirredução
4.
Org Biomol Chem ; 22(12): 2451-2455, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38419463

RESUMO

An efficient synthesis of sulfone structures through selenonium salts and sodium sulfinates was developed. Under the irradiation of a blue LED lamp, the two substrates generate aryl and sulfonyl radicals through the activation of the intermediate electron donor acceptor (EDA) complex, thereby synthesizing aromatic, heteroaromatic and aliphatic sulfones in medium to good yields. The advantages of this strategy are metal-free, mild conditions and the leaving group is recycled to construct new selenonium salts.

5.
Phys Chem Chem Phys ; 26(4): 2986-2994, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38163990

RESUMO

Rare earth elements have high chemical reactivity, and doping them into semiconductor clusters can induce novel physicochemical properties. The study of the physicochemical mechanisms of interactions between rare earth and tin atoms will enhance our understanding of rare earth functional materials from a microscopic perspective. Hence, the structure, electronic characteristics, stability, and aromaticity of endohedral cages MSn16- (M = Sc, Y, La) have been investigated using a combination of the hybrid PBE0 functional, stochastic kicking, and artificial bee colony global search technology. By comparing the simulated results with experimental photoelectron spectra, it is determined that the most stable structure of these clusters is the Frank-Kasper polyhedron. The doping of atoms has a minimal influence on density of states of the pure tin system, except for causing a widening of the energy gap. Various methods such as ab initio molecular dynamics simulations, the spherical jellium model, adaptive natural density partitioning, localized orbital locator, and electron density difference are employed to analyze the stability of these clusters. The aromaticity of the clusters is examined using iso-chemical shielding surfaces and the gauge-including magnetically induced currents. This study demonstrates that the stability and aromaticity of a tin cage can be systematically adjusted through doping.

6.
J Phys Chem A ; 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38973649

RESUMO

In this study, we employ density functional theory along with the artificial bee colony algorithm for cluster global optimization to explore the low-lying structures of TeBnq (n = 3-16, q = 0, -1). The primary focus is on reporting the structural properties of these clusters. The results reveal a consistent doping pattern of the tellurium atom onto the in-plane edges of planar or quasi-planar boron clusters in the most energetically stable isomers. Additionally, we simulate the photoelectron spectra of the cluster anions. Through relative stability analysis, we identify three clusters with magic numbers -TeB7-, TeB10, and TeB12. The aromaticity of these clusters is elucidated using adaptive natural density partitioning (AdNDP) and magnetic properties analysis. Notably, TeB7- exhibits a perfect σ-π doubly aromatic structure, while TeB12 demonstrates strong island aromaticity. These findings significantly contribute to our understanding of the structural and electronic properties of these clusters.

7.
FASEB J ; 36(11): e22602, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36250925

RESUMO

Chronic inflammation is one of the definite factors leading to the occurrence and development of tumors, including prostate cancer (PCa). The androgen receptor (AR) pathway is essential for PCa tumorigenesis and inflammatory response. However, little is known about the AR-regulated NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome pathway in human PCa. In this study, we explored the expression of inflammatory cytokine and AR in high-grade PCa and observed that NLRP3 inflammasome-associated genes were upregulated in high-grade PCa compared with that in low-grade PCa and benign prostatic hyperplasia and were associated with AR expression. In addition, we identified circAR-3-a circRNA derived from the AR gene-which is involved in the AR-regulated inflammatory response and cell proliferation by activating the NLRP3 inflammatory pathway. While circAR-3 overexpression promoted cell proliferation and the inflammatory response, its depletion induced opposite effects. Mechanistically, we noted that circAR-3 mediated the acetylation modification of NLRP3 by KAT2B and then promoted NLRP3 inflammasome complex subcellular distribution and assembly. Disturbing NLRP3 acetylation or blocking inflammasome assembly with an inhibitor suppressed the progression of PCa xenograft tumors. Our findings provide the first evidence that targeting NLRP3 acetylation or inflammasome assembly may be effective in inhibiting PCa progression.


Assuntos
Neoplasias da Próstata , Receptores Androgênicos , Acetilação , Citocinas/metabolismo , Humanos , Inflamassomos/genética , Inflamassomos/metabolismo , Masculino , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Neoplasias da Próstata/metabolismo , RNA Circular , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
8.
PLoS Biol ; 18(8): e3000808, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32817651

RESUMO

Although dysregulation of mitochondrial dynamics has been linked to cellular senescence, which contributes to advanced age-related disorders, it is unclear how Krüppel-like factor 5 (Klf5), an essential transcriptional factor of cardiovascular remodeling, mediates the link between mitochondrial dynamics and vascular smooth muscle cell (VSMC) senescence. Here, we show that Klf5 down-regulation in VSMCs is correlated with rupture of abdominal aortic aneurysm (AAA), an age-related vascular disease. Mice lacking Klf5 in VSMCs exacerbate vascular senescence and progression of angiotensin II (Ang II)-induced AAA by facilitating reactive oxygen species (ROS) formation. Klf5 knockdown enhances, while Klf5 overexpression suppresses mitochondrial fission. Mechanistically, Klf5 activates eukaryotic translation initiation factor 5a (eIF5a) transcription through binding to the promoter of eIF5a, which in turn preserves mitochondrial integrity by interacting with mitofusin 1 (Mfn1). Accordingly, decreased expression of eIF5a elicited by Klf5 down-regulation leads to mitochondrial fission and excessive ROS production. Inhibition of mitochondrial fission decreases ROS production and VSMC senescence. Our studies provide a potential therapeutic target for age-related vascular disorders.


Assuntos
Aneurisma da Aorta Abdominal/genética , Células Endoteliais/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Mitocôndrias/metabolismo , Fatores de Iniciação de Peptídeos/genética , Proteínas de Ligação a RNA/genética , Idoso , Angiotensina II/genética , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Aorta/diagnóstico por imagem , Aorta/metabolismo , Aorta/patologia , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/metabolismo , Aneurisma da Aorta Abdominal/patologia , Senescência Celular/efeitos dos fármacos , Ecocardiografia , Células Endoteliais/patologia , Feminino , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/deficiência , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Fatores de Iniciação de Peptídeos/deficiência , Cultura Primária de Células , Regiões Promotoras Genéticas , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Fator de Iniciação de Tradução Eucariótico 5A
9.
Langmuir ; 39(37): 13296-13302, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37661457

RESUMO

Double emulsions are of great importance for both science and engineering. However, the production of multicore double-emulsion droplets is challenging and normally requires sophisticated microfluidic devices, which limits their availability to broader communities. Here, we propose a simple, precise, and scalable batch method for producing double emulsions with monodispersed multicores at milliliter per minute rates, using the most common means in laboratory, temperature. By rapidly cooling liquid crystal emulsions, the introduced temperature gradient around the emulsion droplets leads to the injection of monodispersed guest droplets to form double-emulsion droplets. The number of injected water droplets can be precisely controlled by adjusting the thermally induced mechanical force through the temperature difference and the cooling rate. In contrast to conventional microfluidic fabrication, this method processes all emulsion droplets simultaneously in a noncontact and in situ manner. Therefore, it has great flexibility, allows multiple processing of double emulsions of arbitrary shape, has good capacity for mass production, and offers excellent compatibility with technologies such as microfluidics. Finally, we demonstrate that temperature changes can also be used to release the inner droplets from the double emulsion. The proposed method offers a reversible tool for processing double emulsions with minimal cost and expertise and is applicable to droplet-based microsystems in materials science, photonics, sensors, pharmaceuticals, and biotechnology.

10.
J Org Chem ; 88(14): 10164-10170, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37410990

RESUMO

A convenient method for the synthesis of indoles has been developed by the sequential orchestration of the cross-coupling reaction of o-haloaniline and PIFA oxidation of the resulting 2-alkenylanilines. A highlight of this two-step indole synthesis is a modular strategy which is applicable to both acyclic and cyclic starting materials. Particularly noteworthy is the regiochemistry that is complementary to the Fischer indole synthesis and related variants. Direct preparation of N-H indoles with no N-protecting group is also advantageous.

11.
Aging Male ; 26(1): 2220399, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37312581

RESUMO

Some evidence have suggested that various nutrients and inflammatory factors might influence the lower urinary tract function. However, the correlation between diet and urinary flow rate (UFR) is not clear. Our study aimed to evaluate the association between the dietary inflammatory index (DII) and UFR. We performed a cross-sectional analysis using data from the National Health and Nutrition Examination Survey (NHANES) database from 2009-2016. The dependent and independent variables were UFR and DII score, respectively. Dietary information was collected by 24-hour dietary recall interviews method, and DII scores were computed based on it. Tertiles group was divided according to DII scores. The study included 17,114 participants for whom data on DII and UFR were available, with a mean age of 35.68 ± 20.96 years. Participants with higher DII score presented lower UFR levels (ß= -0.05; 95% CI: [-0.06-0.04]). In addition, the risk of UFR decline elevated significantly gradual across DII score tertiles (p for trend <0.001). Our findings revealed that increased intake of pro-inflammatory diet, as a higher DII score, is correlated with decreased UFR. These results might be useful for the public health system to provide primary prevention recommendations for lower urinary tract voiding problem, but further high-quality prospective research is needed.


Assuntos
Dieta , Humanos , Inquéritos Nutricionais , Estudos Transversais , Estudos Prospectivos , Bases de Dados Factuais
12.
Org Biomol Chem ; 21(30): 6192-6196, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37466287

RESUMO

A visible-light-mediated protocol to prepare 1,2-diamines has been successfully explored based on the photoredox/Brønsted acid co-catalyzed α-amino alkylations of imines with tertiary amines. Both ketimines and aldimines are applicable to this transformation. Various 1,2-diamines with different functional groups were produced in moderate to excellent yields. Moreover, this approach could be performed on a gram scale, showing its practicality.

13.
J Med Internet Res ; 25: e41882, 2023 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-36951921

RESUMO

BACKGROUND: Vaccine hesitancy has been deemed one of the top 10 threats to global health. Antivaccine information on social media is a major barrier to addressing vaccine hesitancy. Understanding how vaccine proponents and opponents interact with each other on social media may help address vaccine hesitancy. OBJECTIVE: We aimed to examine conversations between vaccine proponents and opponents on Reddit to understand whether homophily in web-based conversations impedes opinion exchange, whether people are able to accommodate their languages to each other in web-based conversations, and whether engaging with opposing viewpoints stimulates higher levels of analytical thinking. METHODS: We analyzed large-scale conversational text data about human vaccines on Reddit from 2016 to 2018. Using deep neural network language models and computer-assisted conversational analyses, we obtained each Redditor's stance on vaccines, each post's stance on vaccines, each Redditor's language coordination score, and each post or comment's analytical thinking score. We then performed chi-square tests, 2-tailed t tests, and multilevel modeling to test 3 questions of interest. RESULTS: The results show that both provaccine and antivaccine Redditors are more likely to selectively respond to Redditors who indicate similar views on vaccines (P<.001). When Redditors interact with others who hold opposing views on vaccines, both provaccine and antivaccine Redditors accommodate their language to out-group members (provaccine Redditors: P=.044; antivaccine Redditors: P=.047) and show no difference in analytical thinking compared with interacting with congruent views (P=.63), suggesting that Redditors do not engage in motivated reasoning. Antivaccine Redditors, on average, showed higher analytical thinking in their posts and comments than provaccine Redditors (P<.001). CONCLUSIONS: This study shows that although vaccine proponents and opponents selectively communicate with their in-group members on Reddit, they accommodate their language and do not engage in motivated reasoning when communicating with out-group members. These findings may have implications for the design of provaccine campaigns on social media.


Assuntos
Mídias Sociais , Vacinas , Humanos , Idioma , Redes Neurais de Computação , Computadores
14.
Sensors (Basel) ; 23(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37177536

RESUMO

Structural health monitoring is currently a crucial measure for the analysis of structural safety. As a structural asset management approach, it can provide a cost-effective measure and has been used successfully in a variety of structures. In recent years, the development of fiber optic sensing technology and vision sensing technology has led to further advances in structural health monitoring. This paper focuses on the basic principles, recent advances, and current status of applications of these two sensing technologies. It provides the reader with a broad review of the literature. It introduces the advantages, limitations, and future directions of these two sensing technologies. In addition, the main contribution of this paper is that the integration of fiber optic sensing technology and vision sensing technology is discussed. This paper demonstrates the feasibility and application potential of this integration by citing numerous examples. The conclusions show that this new integrated sensing technology can effectively utilize the advantages of both fields.

15.
Molecules ; 28(13)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37446733

RESUMO

The growth behavior, stability, electronic and magnetic properties of the Gd2Sin- (n = 3-12) clusters are reported, which are investigated using density functional theory calculations combined with the Saunders 'Kick' and the Artificial Bee Colony algorithm. The lowest-lying structures of Gd2Sin- (n = 3-12) are all exohedral structures with two Gd atoms face-capping the Sin frameworks. Results show that the pentagonal bipyramid (PB) shape is the basic framework for the nascent growth process of the present clusters, and forming the PB structure begins with n = 5. The Gd2Si5- is the potential magic cluster due to significantly higher average binding energies and second order difference energies, which can also be further verified by localized orbital locator and adaptive natural density partitioning methods. Moreover, the localized f-electron can be observed by natural atomic orbital analysis, implying that these electrons are not affected by the pure silicon atoms and scarcely participate in bonding. Hence, the implantation of these elements into a silicon substrate could present a potential alternative strategy for designing and synthesizing rare earth magnetic silicon-based materials.


Assuntos
Algoritmos , Silício , Proliferação de Células , Ciclo Celular , Elétrons
16.
Opt Express ; 30(15): 26018-26026, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236800

RESUMO

Processing of mesoscale structures of soft matter and liquid is of great importance in both science and engineering. In this work, we introduce the concept of laser-assisted micromachining to this field and inject a certain number of microdroplets into a preselected location on the surface of a liquid crystal drop through laser irradiation. The impact of laser energy on the triggered injection is discussed. The sequentially injected microdroplets are spontaneously captured by the defect ring in the host drop and transported along this defect track as micro-cargos. By precisely manipulating the laser beam, the tailored injection of droplets is achieved, and the injected droplets self-assemble into one necklace ring within the host drop. The result provides a bottom-up approach for the in-situ and three-dimensional microfabrication of droplet structure of soft matter using a laser beam, which may be applicable in the development of optical and photonic devices.

17.
World J Urol ; 40(2): 545-552, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34716773

RESUMO

PURPOSE: It has been reported that polycyclic aromatic hydrocarbons (PAHs) exposure was associated with the increasing risk of various diseases. Utilizing the data from the general population of the U.S., we tried to assess the association between PAHs exposure and KS. METHODS: The dataset was extracted from National Health and Nutrition Examination Survey (NHANES) 2007-2016. The hydroxylated metabolites of polycyclic aromatic hydrocarbons (OH-PAHs) were detected as representative of urinary PAHs. Ranking-based PAHs score was used to evaluate the total PAHs exposure burden. Multivariable logistic regression analyses were performed to assess the association between PAHs exposure and KS after adjusting a series of confounding factors. RESULTS: 8975 eligible participants were included. In multivariable logistic regression analyses, after adjusting confounding variables, 2-hydroxynaphthalene (OR 1.38, 1.16-1.65; p = 0.038) and 9-hydroxyfluorene (OR 1.39, 1.06-1.84, p = 0.019) were still observed to have significant positive correlations with the prevalence of KS, respectively. The incidence of KS increased significantly with the increase of total PAHs burden (p for trend = 0.011). Significant interaction effects were observed in the subgroup of gender (p for interaction < 0.05). Among female participants, PAHs exposure was more significantly correlated with KS. Higher 2-hydroxynaphthalene (OR 1.94, 1.39-2.70; p < 0.001), 1-hydroxyphenanthrene (OR 1.57, 1.07-2.30; p = 0.022) and 2-hydroxyphenanthrene (OR 1.85, 1.11-3.06; p = 0.018) were significantly associated with the increased incidence of KS in women. CONCLUSIONS: There is a significant association between a high level of PAHs exposure and increased prevalence of KS. In particular, in the female population, the relationship between PAHs exposure and KS is especially significant.


Assuntos
Cálculos Renais , Hidrocarbonetos Policíclicos Aromáticos , Biomarcadores , Feminino , Humanos , Inquéritos Nutricionais , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Prevalência
18.
Soft Matter ; 18(35): 6638-6644, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36004571

RESUMO

Vertical nanostructures have been found to induce the deformation of the nuclear envelope during cell adhesion. However, there has been a lack of quantitative analysis of the influence of nanostructures morphology on the degree of nuclear deformation. Here, a theoretical model was proposed to investigate the mechanism of nuclear deformation by analyzing the mechanical force balance. Based on the established model, we analyzed the effects of the morphology of the nanopillar array on nuclear deformation and gave the quantitative relationship of the deformation depth of the nucleus with the pitch and radius of nanopillars. Our theoretical results seem to show broad agreements with experimental observations, which implies that the work can provide useful guidance to the design of nanostructures for biomedical applications.


Assuntos
Nanoestruturas , Adesão Celular , Núcleo Celular , Nanoestruturas/química
19.
Org Biomol Chem ; 20(21): 4427-4430, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35587033

RESUMO

A novel photo-induced C-H arylation of (hetero)arenes has been developed. Aryl selenonium salts as an aryl source led to the arylation of aromatic (hetero)cyclic compounds via C-Se bond activation under blue LED irradiation. The method simply utilizes the safe and clean energy source and yields a range of site-selective biphenyl or bi-heterocyclic products in medium to good yields. Furthermore, the borylation and Sonogashira coupling of aryl selenonium salts proceed in good yields as well. From the results, it is shown that selenonium salts are more reactive than sulfonium salts.


Assuntos
Luz , Sais , Catálise
20.
Brain Topogr ; 35(4): 525-535, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35006499

RESUMO

To study the associations between RDH12 gene mutations, fundus types, and clinical manifestations. In total, 46 patients with inherited eye diseases caused by RDH12 gene mutations were included in this study. High-throughput chip capture sequencing, Sanger sequencing, and gene panel detection were used to determine that RDH12 was the pathogenic gene. All patients underwent the following detailed ophthalmic examinations: visual acuity, visual field, intraocular pressure, fundus photography, electroretinography, and optical coherence tomography (OCT). Statistical analysis was used to evaluate the clinical phenotype. A total of 32 mutations were identified in 46 patients. The most common mutations were c.437T > A, c.184C > T, and c.524C > T; the corresponding amino acid changes were p.Val146Asp, p.Arg62Ter, and p.Ser175Leu. Of the 46 patients, retinitis pigmentosa (RP) was found in 31 (68.9%); leber congenital amaurosis (LVA) was found in 11 (24.4%); early onset of severe retinal dystrophy (EOSRD) was found in one (2.2%); cone rod dystrophy (CORD) was found in one (2.2%); and Stargardt disease was found in one (2.2%). There was a significant difference in best-corrected visual acuity among patients based on fundus type (p = 0.0124). Linear trend analysis showed that best-corrected visual acuity gradually decreased as the fundus type increased in severity. In addition, there was a significant difference in the incidence of night blindness among patients with different fundus types (p = 0.0429): types I and IV fundi were associated with the highest incidences of night blindness. RDH12 gene mutation can cause serious inherited retinal diseases, which primarily include RP and LCA. Combined with clinical symptoms and fundus types, the progression of the disease can be characterized and used to guide genetic diagnosis and gene therapy.


Assuntos
Oftalmopatias Hereditárias , Cegueira Noturna , Retinose Pigmentar , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Oftalmopatias Hereditárias/diagnóstico , Oftalmopatias Hereditárias/genética , Humanos , Mutação/genética , Cegueira Noturna/diagnóstico por imagem , Cegueira Noturna/genética , Distrofias Retinianas , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética
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