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1.
Nanotechnology ; 35(16)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38154139

RESUMO

Preparing Cd3As2, which is a three-dimensional (3D) Dirac semimetal in certain crystal orientation, on Si is highly desirable as such a sample may well be fully compatible with existing Si CMOS technology. However, there is a dearth of such a study regarding Cd3As2films grown on Si showing the chiral anomaly. Here,for the first time, we report the novel preparation and fabrication technique of a Cd3As2(112) film on a Si (111) substrate with a ZnTe (111) buffer layer which explicitly shows the chiral anomaly with a nontrivial Berry's phase ofπ. Despite the Hall carrier density (n3D≈9.42×1017cm-3) of our Cd3As2film, which is almost beyond the limit for the portents of a 3D Dirac semimetal to emerge, we observe large linear magnetoresistance in a perpendicular magnetic field and negative magnetoresistance in a parallel magnetic field. These results clearly demonstrate the chiral magnetic effect and 3D Dirac semimetallic behavior in our silicon-based Cd3As2film. Our tailoring growth of Cd3As2on a conventional substrate such as Si keeps the sample quality, while also achieving a low carrier concentration.

2.
Oncologist ; 25(1): e16-e23, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31371522

RESUMO

BACKGROUND: The clinicopathological features and prognosis of breast cancer in Asia are different from those in the Western countries. Tumor-infiltrating immune cells can influence the outcome of patients with breast cancer, but they have not been systemically evaluated in Asian patients with breast cancer. METHODS: We compared the immune score, composition, and prognostic impact of infiltrating immune cells between Asian and Western patients with breast cancer by analyzing gene expression profiles from eight Gene Expression Omnibus data sets and The Cancer Genome Atlas data set. The Estimation of Stromal and Immune Cells in Malignant Tumours Using Expression Data (ESTIMATE) and Cell Type Identification by Estimating Relative Subsets of Known RNA Transcripts (CIBERSORT) algorithms were used to determine the immune score and composition of tumor-infiltrating immune cells, respectively. FINDINGS: This study included 462 Asian patients and 2,186 Western patients. Tumors of Asian patients had significantly higher immune score, particularly in the luminal B and HER2-enriched subtypes. High immune score was associated with favorable prognosis in both Asian and Western patients, and Asian race with a high ESTIMATE immune score provided additional power to predict longer disease-free survival. Activated CD4 T cells and M2 macrophages were the most strongly associated with survival in both Asian and Western patients. INTERPRETATION: Our study highlights the difference in tumor immune microenvironments between Asian and Western patients. The higher ESTIMATE immune score, which represents more abundant tumor-infiltrating immune cells, in tumors of Asian patients partly explains their favorable prognosis. IMPLICATIONS FOR PRACTICE: The tumor microenvironment serves as an interface that affects the human body's reaction to cancer cells. Evidence has revealed that tumor-infiltrating immune cells were associated with patient prognosis. This study demonstrated the disparity of tumor microenvironments and their prognostic impact between Asian and Western patients with breast cancer. The differences in immune score partially explained the racial survival differences noted in recent studies. Integrated analysis of tumor cells, tumor microenvironment, and racial effect may significantly improve recurrence risk prediction for patients with stage I-III breast cancer. Because the effect of tumor microenvironment varies across different populations, a model of interaction between immune score and race/ethnicity is recommended in accessing the risk of patients with cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Microambiente Tumoral/imunologia , Povo Asiático , Neoplasias da Mama/patologia , Feminino , Disparidades em Assistência à Saúde , Humanos , Prognóstico
3.
Org Biomol Chem ; 18(5): 988-998, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31942895

RESUMO

An efficient one-pot two-step sequential reaction for the synthesis of biologically active 3-hydroxyisoindolin-1-one derivatives from 2-iodobenzamide derivatives and various substituted benzyl cyanides in the presence of CuCl and cesium carbonate in DMSO is reported. Furthermore, 3-hydroxyisoindolinone derivatives possessing bromo substituents were obtained from 2-iodobenzamide and 2-bromobenzyl cyanide substrates in two steps. Benzyl cyanide has been successfully used for the first time as a benzoyl synthon for the synthesis of 3-hydroxyisoindolin-1-ones. Interestingly, the mechanism of formation of 3-hydroxyisoindolin-1-ones is a novel pathway that involves carbon degradation followed by ring contraction.

4.
J Org Chem ; 84(6): 3036-3044, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30359006

RESUMO

An efficient method for the synthesis of polysubstituted cyclopentene and cyclopenta[ b]carbazole derivatives through the iodine-promoted electrocyclization of substituted indoles and 4-arylidene-3,6-diarylhex-2-en-5-ynal derivatives is reported. Polysubstituted cyclopentene derivatives were produced through 4π electrocyclization reactions with indole, 7-methylindole, and 5-bromoindole as coupling partners, whereas cyclopenta[ b]carbazole derivatives were produced via 6π electrocyclization in the case of methoxy (-OMe)-substituted indoles. The methods reported herein diastereo- and regioselectively proceed under straightforward and mild conditions.

5.
J Org Chem ; 83(17): 10241-10247, 2018 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-29999313

RESUMO

The copper-catalyzed reaction of aryl aldehydes with 2-iodobenzylcyanides afforded 2-aryl-3-cyanobenzofurans in isolated yields of up to 74% in a cascade manner, which involves Knoevenagel condensation, aryl hydroxylation, oxa-Michael addition, and aromatization reactions. Conversely, 2-halo benzaldehydes as reacting partners with 2-iodobenzylcyanide regioselectively furnished dibenzo[ b,f]oxepine-10-carbonitrile derivatives up to 85% isolated yields via tandem Knoevenagel condensation, aryl hydroxylation, and Ullmann coupling reactions.

6.
J Org Chem ; 82(4): 1961-1968, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28177250

RESUMO

A concise route for the synthesis of indenoisoquinoline derivatives from 2-iodobenzamide and 1,3-indanedione derivatives in the presence of copper(II) chloride and cesium carbonate in acetonitrile solvent is reported. A wide variety of 2-iodobenzamide derivatives and indandiones could be used to synthesize indenoisoquinoline derivatives and other fused indenoisoquinoline in moderate to good yields. This methodology was adapted for the one-step synthesis of a series of clinically active topoisomerase I inhibitors such as NSC 314622, LMP-400, LMP-776.


Assuntos
Cobre/química , Indenos/síntese química , Isoquinolinas/síntese química , Catálise , Cristalografia por Raios X , Indenos/química , Isoquinolinas/química , Modelos Moleculares , Estrutura Molecular
7.
J Org Chem ; 82(14): 7280-7286, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28696696

RESUMO

An efficient approach for the synthesis of benzo-fused pyridoindolone derivatives via a one-pot copper catalyzed tandem reaction of 2-iodobenzamides with 2-iodobenzylcyanides has been developed. Using this protocol, benzo-fused pyridoindolone derivatives are obtained in high yields in a relatively short period of time under mild reaction conditions. To the best of our knowledge, this is the first approach where one can synthesize free indole N-H benzo-fused pyridoindolones. Also, both indole and pyridone cores are constructed during the course of the reaction. The methodology shows good functional group tolerance and allows synthesis of thiophene-fused pyridoindolones and fused indolobenzonaphthyridone derivatives.

9.
Ecotoxicol Environ Saf ; 124: 37-41, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26454073

RESUMO

Diarrheagenic Escherichia coli (DEC) are the most common agents of diarrhea. Waterborne DEC could pose a potential health risk to human through agricultural, household, recreational, and industrial use. There are few published reports on the detection of DEC and its seasonal distribution in aquatic environments. The presence of DEC in different types of aquatic environments was investigated in this study. Water samples were collected from major rivers, water reservoirs, and recreational hot springs throughout Taiwan. Moreover, an intensive water sampling plan was carried out along Puzih River. The detection of DEC target genes was used to determine the presence of enterotoxigenic E. coli (ETEC), enteropathogenic E. coli (EPEC), and Shiga toxin-producing E. coli (STEC). Among the 383 water samples analyzed, DEC was found in 122 (31.8%) samples. The detection rate varied by genotype, raging from 3.6% for STEC to 17.2% for EPEC. The DEC detection rate was higher from river waters than reservoirs and hot springs. In addition, DEC was detected at a higher rate in spring and summer. The presence of EPEC was significantly associated with total coliform levels among hot spring samples. Moreover, the presence of ETEC in river water samples was associated with heterotrophic plate counts. Water with EPEC differed significantly in pH from Puzih River samples. These results suggest that seasonal characteristics may affect the presence of DEC in different aquatic environments, and water quality indicators may be indicative of the presence of DEC.


Assuntos
Escherichia coli Enteropatogênica/isolamento & purificação , Escherichia coli Enterotoxigênica/isolamento & purificação , Fontes Termais/microbiologia , Rios/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Abastecimento de Água , Diarreia , Infecções por Escherichia coli , Humanos , Estações do Ano , Taiwan
10.
Molecules ; 20(12): 22499-519, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26694335

RESUMO

An easy and efficient procedure for the synthesis of 4-indolylquinoline derivatives is described. This process involves two steps, the first of which is the Michael addition of indole to nitrochalcones promoted by sulfamic acid under solvent free conditions and the second step is a reductive cyclization of the indolylnitrochalcone intermediates to 4-indolylquinoline derivatives by Fe/HCl in ethanol. In both steps, the reactions are clean and the yields of products are high.


Assuntos
Chalconas/química , Cloretos/química , Compostos Férricos/química , Ácido Clorídrico/química , Indóis/síntese química , Quinolinas/síntese química , Ciclização , Oxirredução , Ácidos Sulfônicos/química
11.
Molecules ; 20(6): 10910-27, 2015 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-26076111

RESUMO

An efficient and straight forward procedure for the syntheses of bicyclic isoxazole/isoxazoline derivatives from the corresponding dimethyl-2-(2-nitro-1-aryl/alkyl)-2-(prop-2-yn-1yl)malonates or dimethyl 2-allyl-2-(2-nitro-1-aryl/alkyl ethyl)malonate is described. High yields and simple operations are important features of this methodology.


Assuntos
Reação de Cicloadição , Isoxazóis/síntese química , Óxido Nítrico/química
12.
J Org Chem ; 79(4): 1842-9, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24460519

RESUMO

An efficient FeCl3 catalyzed protocol for the synthesis of amino functionalized indolylnitroalkanes from easily available precursor indolylnitroalkenes and substituted amines has been developed. Regioselective C-alkylation in the presence of free amino substituted arenes occurred. The scope of this methodology shows good functional group tolerance, and further, this protocol was used to prepare indolylquinoline derivatives.


Assuntos
Aminas/química , Cloretos/química , Compostos Férricos/química , Indóis/química , Nitrocompostos/química , Alquilação , Catálise
13.
Org Biomol Chem ; 12(41): 8247-56, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25203199

RESUMO

The molecular iodine-promoted reaction of 2-(2-phenylethynyl)-Morita-Baylis-Hillman adducts is reported. In the presence of I2, naphthyl ketone derivatives are produced, whereas in the presence of I2/K3PO4, iodo-substituted isochromene derivatives are produced.


Assuntos
Alcinos/química , Hidrocarbonetos Iodados/síntese química , Iodo/química , Cetonas/síntese química , Cristalografia por Raios X , Hidrocarbonetos Iodados/química , Cetonas/química , Modelos Moleculares , Estrutura Molecular
14.
Sci Rep ; 14(1): 15176, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956114

RESUMO

Assessing programmed death ligand 1 (PD-L1) expression through immunohistochemistry (IHC) is the golden standard in predicting immunotherapy response of non-small cell lung cancer (NSCLC). However, observation of heterogeneous PD-L1 distribution in tumor space is a challenge using IHC only. Meanwhile, immunofluorescence (IF) could support both planar and three-dimensional (3D) histological analyses by combining tissue optical clearing with confocal microscopy. We optimized clinical tissue preparation for the IF assay focusing on staining, imaging, and post-processing to achieve quality identical to traditional IHC assay. To overcome limited dynamic range of the fluorescence microscope's detection system, we incorporated a high dynamic range (HDR) algorithm to restore the post imaging IF expression pattern and further 3D IF images. Following HDR processing, a noticeable improvement in the accuracy of diagnosis (85.7%) was achieved using IF images by pathologists. Moreover, 3D IF images revealed a 25% change in tumor proportion score for PD-L1 expression at various depths within tumors. We have established an optimal and reproducible process for PD-L1 IF images in NSCLC, yielding high quality data comparable to traditional IHC assays. The ability to discern accurate spatial PD-L1 distribution through 3D pathology analysis could provide more precise evaluation and prediction for immunotherapy targeting advanced NSCLC.


Assuntos
Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas , Imunofluorescência , Imageamento Tridimensional , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Antígeno B7-H1/metabolismo , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/diagnóstico , Imageamento Tridimensional/métodos , Imunofluorescência/métodos , Imuno-Histoquímica/métodos , Microscopia Confocal/métodos , Biomarcadores Tumorais/metabolismo
15.
J Org Chem ; 78(17): 8872-9, 2013 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-23944682

RESUMO

A protocol for the N-bromosuccinimide (NBS)- and trichloroisocyanuric acid (TCCA)-mediated synthesis of novel 2-halomethylene-3-oxoketoximes via one-pot halogenation/oxidation of isoxazoline N-oxide derivatives is described here. The keto functionality of 3-ketoximes was selectively reduced by lithiumaluminum hydride to synthesize an unprecedented type of Baylis-Hillman oxime, which underwent N-O coupling to produce new isoxazoline N-oxide derivative.


Assuntos
Benzofenonas/síntese química , Halogênios/química , Isoxazóis/química , Óxidos/química , Oximas/síntese química , Benzofenonas/química , Cristalografia por Raios X , Íons/química , Modelos Moleculares , Estrutura Molecular , Oximas/química
16.
J Org Chem ; 77(19): 8451-64, 2012 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-22967265

RESUMO

A simple and easy route to the synthesis of a variety of structurally diverse indolylquinolines, indolylacridines, and indolylcyclopenta[b]quinoline derivatives via the reductive cyclization of C-alkylated indole derivatives, derived from acyclic as well as cyclic Baylis-Hillman adducts with indoles, is described. An unusual in situ [1,3]-sigmatropic rearrangement of the indole nucleus was observed during the reductive cyclicization of α-regioselective B-H adducts containing indoles to produce indolylacridines and indolylcyclopenta[b]quinoline derivatives.


Assuntos
Acridinas/síntese química , Indóis/síntese química , Quinolinas/síntese química , Acridinas/química , Alquilação , Ciclização , Indóis/química , Estrutura Molecular , Quinolinas/química
17.
J Org Chem ; 77(15): 6495-504, 2012 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-22809001

RESUMO

The unusual alcohol mediated formation of 4-oxo-2-aryl-4H-chromene-3-carboxylate (flavone-3-carboxylate) derivatives from 4-hydroxycoumarins and ß-nitroalkenes in an alcoholic medium is described. The transformation occurs via the in situ formation of a Michael adduct, followed by the alkoxide ion mediated rearrangement of the intermediate. The effect of the different alcohol and nonalcohol media on the reaction was investigated.


Assuntos
4-Hidroxicumarinas/química , Álcoois/química , Benzopiranos/síntese química , Benzopiranos/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
18.
J Org Chem ; 77(11): 5022-9, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22512674

RESUMO

A facile and rapid synthesis of isocoumarin derivatives using a copper-catalyzed tandem C-C/C-O coupling strategy from readily available substrates is described. The reactions of a wide range of 2-iodo-N-phenyl benzamides and acyclic diketones as starting materials were investigated.

19.
Molecules ; 17(5): 5081-94, 2012 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-22555297

RESUMO

A convenient one-pot preparation of 2-methyl-3-(phenylthiomethyl)quinolines from Morita-Baylis-Hillman adducts via conjugate addition of thiols followed by reductive cyclization with Fe/AcOH was developed. The 2-methyl-3-(phenylthiomethyl)quinolines were transformed into 2-methyl-3-(phenylsulfonylmethyl)quinolines via m-CPBA-mediated oxidation.


Assuntos
Quinolinas/síntese química , Compostos de Sulfidrila/química , Sulfonas/química , Ácido Acético/química , Ciclização , Ferro/química , Estrutura Molecular , Oxirredução , Estereoisomerismo
20.
Molecules ; 17(11): 13662-72, 2012 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-23169264

RESUMO

Upon treatment with phenyl dichlorophosphate (PhOP=OCl(2)) in acetonitrile at ambient temperature, a variety of ketoximes underwent a Beckmann rearrangement in an effective manner to afford the corresponding amides in moderate to high yields.


Assuntos
Compostos Organofosforados/química , Oximas/química , Acetonitrilas/química , Acetofenonas/química , Amidas/síntese química , Modelos Químicos , Solventes/química , Temperatura
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