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1.
J Am Chem Soc ; 146(23): 16148-16160, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38820566

RESUMO

Functional assembly of nonlinear optical (NLO) motifs with a large optical anisotropy is vital to the development of advanced NLO and birefringent materials. In this work, we highlight that, in addition to heteroatomic NLO motifs, homoatomic anionic clusters formed by aggregated anions (S, Se, Te) exhibit diverse chain-, ring-, and cage-like chemical structures as well as one-, two-, and three-dimensional motif alignments. The rich structural chemistry enables homoatomic polychalcogenides (HAPCs) to exhibit asymmetric structural features and anisotropic optical properties, with great potential for NLO and birefringent performance. Focusing on totally 55 binary HAPCs A2Qn (n = 2, 3, 4, 5; A = Na, K, Rb, Cs; Q = S, Se, Te) and their ternary analogues, we employ the state-of-the-art first-principles approach to systematically investigate the modulation evolution of their NLO and birefringent properties. Remarkably, Rb2Te3 and Na2TeSe2 exhibit rarely colossal birefringence (>1.0@10 µm) and NLO effects (>20 × AgGaS2), much larger than conventional NLO chalcogenides. Na2Te3 presents the largest birefringence to date (∼3.48@1, 2.72@2, 2.34@10 µm), indicating the unique structural superiority of HAPC in terms of ultra-large birefringence. By mining the intrinsic mechanism, the HAPC anionic groups are identified as novel mid-infrared NLO "material genes", furnishing unique NLO and birefringent performance for the design of novel optoelectronic materials.

2.
J Org Chem ; 78(2): 455-65, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23214918

RESUMO

The enantioselective total syntheses of the potent immunosuppressant FR901483 (1) and its 8-epimer (47) have been accomplished. Our approach features the use of building block 6 as the chiron, the application of the one-pot amide reductive bis-alkylation method to construct the chiral aza-quaternary center (dr = 9:1), regio- and diastereoselective intramolecular aldol reaction to build the bridged ring, and RCM to form the 3-pyrrolin-2-one ring.


Assuntos
Compostos Aza/química , Imunossupressores/química , Imunossupressores/síntese química , Compostos Organofosforados/química , Compostos Organofosforados/síntese química , Alquilação , Espectroscopia de Ressonância Magnética , Estereoisomerismo
3.
Zhongguo Zhong Yao Za Zhi ; 38(8): 1247-50, 2013 Apr.
Artigo em Zh | MEDLINE | ID: mdl-23944044

RESUMO

To study clinical efficacy of Zhennaoning capsules in treating cases with cerebral arteriosclerosis, and analyze its economic benefits. Totally 254 cases with cerebral arteriosclerosis were randomly divided into two groups according to their doctor-consulting sequence: the test group (n = 128) that was administered with Zhennaoning capsules, and the control group (n = 126) that was administered with Yangxueqingnao granules. A double-blind parallel-controlled study was conducted for four weeks, in order to observe the clinical efficacy and adverse effects of the two groups, and evaluate their pharmacoeconomics. Additionally, the clinical efficacy and safety of Zhennaoning capsules in treating cerebral arteriosclerosis, as well as its pharmacoeconomics were also discussed. This study showed that Zhennaoning capsules had a better efficacy than its control drug Yangxueqingnao granules in relieving traditional Chinese medicinal syndromes (according to traditional Chinese medicinal syndrome coring, efficacy and cure rate), suggesting a statistical significance (P < 0.01). Despite statistical significance showed from the differences in the remaining indexes and the occurrence rate of adverse effects, the test group displayed a lower cost effectives than the control group (P < 0.01). Zhennaoning capsules have a better clinical efficacy in treating cases with cerebral arteriosclerosis than Yangxueqingnao granules, demonstrating safe clinical application and better economic advantages.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Arteriosclerose Intracraniana/tratamento farmacológico , Arteriosclerose Intracraniana/economia , Fitoterapia , Idoso , Cápsulas , Estudos de Casos e Controles , Análise Custo-Benefício , Método Duplo-Cego , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
4.
Anal Chem ; 82(23): 9925-31, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21033676

RESUMO

We have developed a novel multiplexed bead-based mesofluidic system (MBMS) based on the specific recognition events on the surface of a series of microbeads (diameter 250 µm) arranged in polydimethylsiloxane (PDMS) microchannels (diameter 300 µm) with the predetermined order and assembled an apparatus implementing automatically the high-throughput bead-based assay and further demonstrated its feasibility and flexibility of gene diagnosis and genotyping, such as ß-thalassemia mutation detection and HLA-DQA genotyping. The apparatus, consisting of bead-based mesofluidic PDMS chip, liquid-processing module, and fluorescence detection module, can integrate the procedure of automated-sampling, hybridization reactions, washing, and in situ fluorescence detection. The results revealed that MBMS is fast, has high sensitivity, and can be automated to carry out parallel and multiplexed genotyping and has the potential to open up new routes to flexible, high-throughput approaches for bioanalysis.


Assuntos
Antígenos HLA-DQ/genética , Hibridização in Situ Fluorescente/métodos , Talassemia beta/genética , Dimetilpolisiloxanos/química , Genótipo , Cadeias alfa de HLA-DQ , Ensaios de Triagem em Larga Escala , Hibridização de Ácido Nucleico/métodos , Mutação Puntual
5.
Anal Biochem ; 401(1): 47-52, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20159005

RESUMO

Gold nanoparticles can be exploited to facilitate a highly sensitive and selective metal ion detection based on fluorescence anisotropy assay with metal ion-dependent DNA-cleaving DNAzyme. This assay allows rapid and accurate determination of metal ions in aqueous medium at room temperature. The method has been demonstrated for determination of Cu(2+) and Pb(2+) ions. The detection sensitivity can be significantly improved to 1 nM by using a "nanoparticle enhancement" approach. Moreover, the assay was also tested in 384-well plates for high-throughput routine determination of toxic metal ions in environmental samples. The method showed distinct advantages over conventional methods in terms of its potential sensitivity, specificity, and ability for rapid response.


Assuntos
DNA Catalítico/química , Poluentes Ambientais/química , Polarização de Fluorescência/métodos , Ouro/química , Nanopartículas Metálicas/química , Metais/química , Poluentes Ambientais/análise , Metais/análise , Temperatura
6.
World J Gastroenterol ; 25(28): 3775-3786, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31391772

RESUMO

BACKGROUND: Pancreatic cancer is a deadly malignancy with aggressive properties. MicroRNAs (miRNAs) participate in the pathogenesis of a variety of diseases and molecular processes by targeting functional mRNAs. Nevertheless, the regulatory role of miRNAs in signaling pathways involved in pancreatic cancer remains largely unknown. AIM: To explore the molecular regulation involved in pancreatic cancer and potential mechanisms of miR-205. METHODS: Microarray analysis was performed to investigate the expression profile of miRNAs in pancreatic cancer. Expression of miR-205 was validated by qRT-PCR. Target prediction and functional enrichment analysis were employed to seek potential target genes of miR-205 and potential functions of these genes. The target binding of miR-205 and adenomatous polyposis coli (APC) was validated by luciferase reporter assay. APC protein expression in pancreatic cancer was validated by qRT-PCR and Western blot. Proliferation was evaluated by MTT and colony formation assays. RESULTS: A large number of miRNAs with altered expression were identified in pancreatic cancer. MiR-205 was significantly up-regulated. APC was found to be a validated target of miR-205 and down-regulated in pancreatic cancer. Proliferation experiments showed that miR-205 could promote cell proliferation in pancreatic cancer by targeting APC. CONCLUSION: The above findings suggested that miR-205 mediated APC regulation contributes to pancreatic cancer development, which could be considered as a novel prognostic biomarker for clinical care.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células/genética , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Cultura Primária de Células , Prognóstico , Células Tumorais Cultivadas , Regulação para Cima
7.
Ther Adv Med Oncol ; 9(12): 741-754, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29449895

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is the most aggressive and deadly primary brain cancer that arises from astrocytes and classified as grade IV. Recently, exosomes have been reported as an essential mediator in diverse cancer carcinogenesis and metastasis. However, their role in GBM is still unclear. In this study, we aimed to investigate whether blood exosomes can be potential clinical diagnostic markers for GBM. METHODS: We used a xenograft orthotopic mouse model to detect the differentially expressed genes in the brain and blood exosomes of original/recurrent GBM. RESULTS: We found that recurrent GBM had stronger growth capacity and lethality than original GBM in the mouse model. A gene microarray of original tumors and blood exosomes from GBM orthotopic xenografts results showed that DNM3, p65 and CD117 expressions increased, whereas PTEN and p53 expressions decreased in both original tumors and blood exosomes. In the recurrent GBM tumor model, DNM3 and p65 showed increased expressions, whereas ST14 and p53 showed decreased expressions in tumor and blood exosomes of the recurrent GBM mouse model. CONCLUSION: In summary, we found that DNM3, p65 and p53 had a similar trend in brain and blood exosomes both for original and recurrent GBM, and could serve as potential clinical diagnostic markers for GBM.

8.
Org Lett ; 14(18): 4834-7, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22937903

RESUMO

A formal enantioselective total synthesis of the potent immunosuppressant FR901483 (1) has been accomplished. Our approach features the use of chiron 6 as the starting material, the application of the one-pot amide reductive bisalkylation method to construct the chiral aza-quaternary center (dr = 9:1), regio- and diastereoselective intramolecular aldol reaction to build the bridged ring, and ring closing metathesis to form the 3-pyrrolin-2-one ring.


Assuntos
Imunossupressores/síntese química , Compostos Organofosforados/síntese química , Aldeídos/química , Imunossupressores/química , Imunossupressores/farmacologia , Estrutura Molecular , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Estereoisomerismo
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