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1.
Opt Lett ; 45(8): 2335-2338, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32287227

RESUMO

Terahertz (THz) sensing of molecular fingerprint enables wide applications in biomedicine and security detection. Conventional detection approaches face big barriers in trace analysis of analyte due to the difficulties of enhancing the broadband molecular absorption. In order to achieve strong broadband wave-matter interaction for the analyte, we propose a method based on THz wave angular scanning on a dielectric metagrating. In virtue of the guided-mode resonance, one can strengthen the local electric field in various trace-amount analytes by tuning the polarization and incident angle, which leads to significant enhancement on the broadband signal of molecular fingerprint. The study paves the way for more applications of THz trace-amount detection.


Assuntos
Análise Espectral/métodos , Absorção Fisico-Química , Impedância Elétrica , Lactose/química
2.
J Pharmacol Exp Ther ; 352(2): 305-14, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25467132

RESUMO

Liver X Receptors (LXRs) α and ß are nuclear hormone receptors that regulate multiple genes involved in reverse cholesterol transport (RCT) and are potential drug targets for atherosclerosis. However, full pan agonists also activate lipogenic genes, resulting in elevated plasma and hepatic lipids. We report the pharmacology of BMS-779788 [2-(2-(1-(2-chlorophenyl)-1-methylethyl)-1-(3'-(methylsulfonyl)-4-biphenylyl)-1H-imidazol-4-yl)-2-propanol], a potent partial LXR agonist with LXRß selectivity, which has an improved therapeutic window in the cynomolgus monkey compared with a full pan agonist. BMS-779788 induced LXR target genes in blood in vivo with an EC50 = 610 nM, a value similar to its in vitro blood gene induction potency. BMS-779788 was 29- and 12-fold less potent than the full agonist T0901317 in elevating plasma triglyceride and LDL cholesterol, respectively, with similar results for plasma cholesteryl ester transfer protein and apolipoprotein B. However, ABCA1 and ABCG1 mRNA inductions in blood, which are critical for RCT, were comparable. Increased liver triglyceride was observed after 7-day treatment with BMS-779788 at the highest dose tested and was nearly identical to the dose response for plasma triglyceride, consistent with the central role of liver LXR in these lipogenic effects. Dose-dependent increases in biliary cholesterol and decreases in phospholipid and bile acid occurred in BMS-779788-treated animals, similar to LXR agonist effects reported in mouse. In summary, BMS-779788, a partial LXRß selective agonist, has decreased lipogenic potential compared with a full pan agonist in cynomolgus monkeys, with similar potency in the induction of genes known to stimulate RCT. This provides support in nonhuman primates for improving LXR agonist therapeutic windows by limiting LXRα activity.


Assuntos
Anticolesterolemiantes/farmacologia , Imidazóis/farmacologia , Fígado/efeitos dos fármacos , Receptores Nucleares Órfãos/agonistas , Sulfonas/farmacologia , Transportadores de Cassetes de Ligação de ATP/sangue , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/sangue , Relação Dose-Resposta a Droga , Agonismo Parcial de Drogas , Imidazóis/administração & dosagem , Imidazóis/sangue , Lipídeos/sangue , Lipogênese/efeitos dos fármacos , Fígado/metabolismo , Receptores X do Fígado , Macaca fascicularis , Masculino , Sulfonas/administração & dosagem , Sulfonas/sangue , Triglicerídeos/metabolismo
3.
Bioorg Med Chem Lett ; 25(2): 372-7, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25435151

RESUMO

A series of biaryl pyrazole and imidazole Liver X Receptor (LXR) partial agonists has been synthesized displaying LXRß selectivity. The LXRß selective partial agonist 18 was identified with potent induction of ATP binding transporters ABCA1 and ABCG1 in human whole blood (EC50=1.2µM, 55% efficacy). In mice 18 displayed peripheral induction of ABCA1 at 3 and 10mpk doses with no significant elevation of plasma or hepatic triglycerides at these doses, showing an improved profile compared to a full pan-agonist.


Assuntos
Transportador 1 de Cassete de Ligação de ATP/sangue , Imidazóis/farmacologia , Fígado/efeitos dos fármacos , Receptores Nucleares Órfãos/agonistas , Pirazóis/farmacologia , Sulfonas/farmacologia , Animais , Agonismo Parcial de Drogas , Humanos , Imidazóis/química , Imidazóis/farmacocinética , Fígado/metabolismo , Receptores X do Fígado , Camundongos , Modelos Moleculares , Estrutura Molecular , Plasma/química , Pirazóis/química , Pirazóis/farmacocinética , Relação Estrutura-Atividade , Sulfonas/química , Sulfonas/farmacocinética , Distribuição Tecidual , Triglicerídeos/metabolismo
4.
J Obstet Gynaecol Res ; 41(9): 1418-25, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26098684

RESUMO

AIM: Evaluation of tubal status is critical in the diagnostic work-up of infertile women. The purpose of this study was to explore the diagnostic efficacy of three-dimensional hysterosalpingo-contrast sonography (3-D HyCoSy) for tubal occlusion. METHODS: MedLine, Embase, Cochrane Library, ScienceDirect, CNKI, Chinese VIP Database, Chinese Wanfang Database and Chinese Biomedicine Database were searched for relevant trials published from June 1994 to August 2013. Meta-DiSc (version 1.4) was used for the meta-analysis. Diagnostic accuracy was determined by pooled estimates of sensitivity and specificity, as well as area under the curve (AUC) and the pooled diagnostic accuracy (Q*) derived from a summary receiver operating characteristic analysis. The heterogeneity test was done using the Cochran Q statistic and the I(2) statistic. Significant difference was defined as P < 0.10 (Q-statistic) or I(2) > 50% (I(2) -statistic) and a random effect model was used to pool data, otherwise the fixed effects model was used. RESULTS: A total of 11 studies (1037 Fallopian tubes) were included in this meta-analysis. The pooled estimates for diagnostic efficacy of 3-D HyCoSy had a sensitivity of 0.92 (95%CI: 0.89-0.94) and specificity of 0.95 (95%CI: 0.93-0.96). AUC and Q* were 0.976 and 0.929, respectively, but there was significant heterogeneity in sensitivity across the included studies. CONCLUSIONS: 3-D HyCoSy had good diagnostic performance in the detection of tubal occlusion.


Assuntos
Doenças das Tubas Uterinas/diagnóstico por imagem , Tubas Uterinas/diagnóstico por imagem , Histerossalpingografia , Infertilidade Feminina/diagnóstico por imagem , Ultrassonografia , Meios de Contraste , Feminino , Humanos , Sensibilidade e Especificidade
5.
ACS Nano ; 17(4): 3383-3393, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36630157

RESUMO

Plasmonic metasurfaces (PMs) functionalized with the monoclonal antibody (mAb) are promising biophotonic sensors for biomolecular interaction analysis and convenient immunoassay of various biomarkers, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants. Previous PM biosensing suffers from the slow affinity detection rate and lack of sufficient immunoassay studies on various SARS-CoV-2 variants. Here, we develop a high-efficiency affinity testing method based on label-free PM sensors with mAbs and demonstrate their binding characteristics to 12 spike receptor binding domain (RBD) variants of SARS-CoV-2. In addition to the research of plasmonic near-field influence on surface biomolecule sensing, we provide a comprehensive report about the Langmuir binding equilibrium of molecular kinetics between 12 SARS-CoV-2 RBD variants and mAb-functionalized PMs, which plays a crucial role in label-free immunosensing. A high-affinity mAb can be combined with the highly sensitive propagating plasmonic mode to boost the detection of SARS-CoV-2 variants. Owing to a better understanding of molecular dynamics on PMs, we develop an ultrasensitive biosensor of the SARS-CoV-2 Omicron variant. The experiments show great distinguishment of P < 0.0001 from respiratory diseases induced by other viruses, and the limit of detection is 2 orders smaller than the commercial colloidal gold immunoassay. Our study shows the label-free biosensing by low-cost wafer-scale PMs, which will provide essential information on biomolecular interaction and facilitate high-precision point-of-care testing for emerging SARS-CoV-2 variants in the future.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2/genética , Anticorpos Monoclonais , Imunoensaio
6.
Biosens Bioelectron ; 235: 115380, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37207584

RESUMO

Prostate-specific antigen (PSA) test is widely used to diagnose early prostate cancer (PCa). Its low sensitivity, especially in the gray zone, usually incurs overtreatment or missed diagnosis. As an emerging tumor marker, exosomes have attracted great interest in non-invasive diagnosis of PCa. However, the quick direct detection of exosomes in serum is still a big challenge for convenient screening of early PCa due to their high-degree heterogeneity and complexity. Here we develop the label-free biosensors based on wafer-scale plasmonic metasurfaces, and establish a flexible spectral methodology of exosomes profiling, which facilitates their identification and quantification in serum. We combine the metasurfaces functionalized by anti-PSA and anti-CD63, respectively, and build a portable immunoassay system to detect serum PSA and exosomes simultaneously within 20 min. Our scheme can discriminate early PCa from benign prostatic hyperplasia with a diagnostic sensitivity of 92.3%, which is much higher that of 58.3% for conventional PSA tests. The receiver operating characteristic analysis in clinical trials demonstrates significant PCa distinguishing capability with an area under the curve up to 99.4%. Our work provides a rapid and powerful approach for precise diagnosis of early PCa, and will inspire more exosomes metasensing studies for other early cancer screening.


Assuntos
Técnicas Biossensoriais , Exossomos , Hiperplasia Prostática , Neoplasias da Próstata , Masculino , Humanos , Antígeno Prostático Específico , Exossomos/patologia
7.
Biosens Bioelectron ; 203: 114038, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121450

RESUMO

Plasmonic metasurface biosensors have great potential on label-free high-throughput clinical detection of human tumor markers. In the past decades, nanopillar and nanohole metasurfaces have become the common choices for plasmonic biosensing, because they typically enable universal simple large-area nanopatterns via a low-cost reproducible fabrication manner. The two kinds of metasurfaces have the complementary shapes and are used to be assumed as the same type of two-dimensional plasmonic nanograting for biosensing. Up to date, there is still a lack of comparison study on their biosensing performance, which is critical to guide their better applications on tumor marker detection. In this study, we compare the bulk/surface refractive index and sensitivity of plasmonic nanopillar (PNP) and plasmonic nanohole (PNH) metasurfaces in order to evaluate their biosensing capabilities. The sensing physics about their space near-field utilization is systematically revealed. The PNH metasurface demonstrates a higher biomolecule sensitivity versus the complementary PNP metasurface, and its limit of detection for bovine serum albumin reaches ∼0.078 ng/mL, which implies a greater potential of detecting cancer biomarkers. We further adopt the PNH metasurfaces for immunoassay of three typical tumor markers by testing clinical human serum samples. The results imply that the immunodetection of alpha-fetoprotein has the most optimal sensing efficiency with the lowest detection concentration (<5 IU/mL), which is much lower than its clinical diagnosis threshold of ∼16.5 IU/mL for medical examination. Our work has not only illuminated the distinct biosensing properties of complementary metasurfaces, but also provided a promising way to boost plasmonic biosensing for point-of-care testing.


Assuntos
Técnicas Biossensoriais , Biomarcadores Tumorais , Técnicas Biossensoriais/métodos , Humanos , Refratometria , Soroalbumina Bovina
8.
Clin Chim Acta ; 510: 599-604, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798513

RESUMO

BACKGROUND: Fetal central nervous system abnormalities often associated with infant death or severe disability. The etiology in fetuses with CNS abnormalities who have normal karyotypes and copy number variants (CNVs) remains unclear, which increases the difficulty in following management and the assessment of prognosis. METHOD: 11 unrelated fetuses with CNS abnormalities and their parents were enrolled. Genomic DNA was obtained and then trios-medical exome sequencing (trios-MES) including 4000 genes (fetuses and their parents) was performed after both karyotyping and chromosome microarray showed negative results. RESULTS: Pathogenic and likely pathogenic variants were identified in five of 11 cases (5/11, 45.5%), including five novel mutations and two recurrent mutations in ISPD, L1CAM, and GRIN2B genes. Most cases (4/5, 80%) carried one or two recessive mutations, indicating a high recurrent risk. CONCLUSION: Exome sequencing should be considered for fetuses with CNS abnormalities following negative results of karyotyping and chromosome array. Trios-MES as one of exome sequencing is a potential method for the diagnosis of these fetuses.


Assuntos
Exoma , Malformações do Sistema Nervoso , Variações do Número de Cópias de DNA/genética , Exoma/genética , Feminino , Feto , Humanos , Cariotipagem , Gravidez , Diagnóstico Pré-Natal , Sequenciamento do Exoma
9.
Eur J Obstet Gynecol Reprod Biol ; 251: 119-124, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32502767

RESUMO

OBJECTIVE: To evaluate the clinical application of medical exome sequencing (MES) for prenatal diagnosis of genetic diseases related to fetal structural anomalies detected by prenatal ultrasound examination. STUDY DESIGN: A total of 105 fetuses with structural anomalies were negative results in both Quantitative fluorescent polymerase chain reaction (QF-PCR) and chromosomal microarray analysis (CMA). Then trio-based MES was further used for identifying the potential monogenic diseases in these fetuses. Coding regions and known pathogenic non-coding regions of over 4000 disease-related genes were interrogated, and variants were classified following the guidelines of American College of Medical Genetics (ACMG). RESULTS: The 105 fetuses with structural anomalies were categorized into 12 phenotypic groups. A definitive diagnosis was achieved in 19% (20/105) of the cases, with the identification of 21 pathogenic or likely pathogenic variants in 14 genes. The proportion of patients with diagnostic genetic variants varied between the phenotypic groups, with the highest diagnostic yield in the cardiovascular abnormalities (44%), followed by the skeletal and limb abnormalities (38%) and brain structural abnormalities (25%). In addition, 12 fetuses were detected variants of unknown significance (VOUS), while the relevance of phenotypes and variants would further evaluated. CONCLUSION: MES can identify the underlying genetic cause in fetal structural anomalies. It can further assist the management of pregnancy and genetic counseling. It was demonstrated the importance of translating prenatal MES into clinical practice.


Assuntos
Exoma , Ultrassonografia Pré-Natal , Feminino , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Diagnóstico Pré-Natal , Sequenciamento do Exoma
10.
Taiwan J Obstet Gynecol ; 59(3): 451-455, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32416898

RESUMO

OBJECTIVE: The L1 cell adhesion molecule (L1CAM) gene, encodes the L1 cell adhesion molecule, is involved in the central nervous system development. Its mutations result in L1 syndrome which is associated with brain malformation and nervous developmental delay. CASE REPORT: We presented three fetuses with hydrocephalus and agenesis of the corpus callosum detected by ultrasound, followed by medical exome sequencing (MES) test with L1CAM mutations: two known missense mutation c.551G > A (p. R184Q) and c.1354G > A (p. G452R), and a novel frameshift mutation c.1322delG which causes the early termination of translation (p. G441Afs∗72). By utilizing multiple computational analysis, all the variants were scored to be likely pathogenic. CONCLUSION: Combined use of ultrasound and MES to identify the molecular etiology of fetal anomalies may contribute to expanding our knowledge of the clinical phenotype of L1 syndrome observed in the south Chinese population.


Assuntos
Sequenciamento do Exoma , Exoma/genética , Feto/anormalidades , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Deficiência Intelectual/diagnóstico , Molécula L1 de Adesão de Célula Nervosa/genética , Paraplegia Espástica Hereditária/diagnóstico , Adulto , Agenesia do Corpo Caloso/diagnóstico , Agenesia do Corpo Caloso/embriologia , Agenesia do Corpo Caloso/genética , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/embriologia , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Hidrocefalia/diagnóstico , Hidrocefalia/embriologia , Hidrocefalia/genética , Deficiência Intelectual/embriologia , Deficiência Intelectual/genética , Mutação , Fenótipo , Gravidez , Paraplegia Espástica Hereditária/embriologia , Paraplegia Espástica Hereditária/genética , Ultrassonografia Pré-Natal
11.
Nanoscale ; 11(19): 9749-9755, 2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31066432

RESUMO

The burgeoning research of graphene and other 2D materials enables many unprecedented metamaterials and metadevices for applications on nanophotonics. The design of on-demand graphene-based metamaterials often calls for the solution of a complex inverse problem within a small sampling space, which highly depends on the rich experiences from researchers of nanophotonics. Conventional optimization algorithms could be used for this inverse design, but they converge to local optimal solutions and take significant computational costs with increased nanostructure parameters. Here, we establish a deep learning method based on an adaptive batch-normalized neural network, aiming to implement smart and rapid inverse design for graphene-based metamaterials with on-demand optical responses. This method allows a quick converging speed with high precision and low computational consumption. As typical complex proof-of-concept examples, the optical metamaterials consisting of graphene/dielectric alternating multilayers are chosen to demonstrate the validity of our design paradigm. Our method demonstrates a high prediction accuracy of over 95% after very few training epochs. A universal programming package is developed to achieve the design goals of graphene-based metamaterials with low absorption and near unity absorption, respectively. Our work may find important design applications in the field of nanoscale photonics based on graphene and other 2D materials.

12.
ACS Med Chem Lett ; 7(12): 1207-1212, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27994765

RESUMO

Introducing a uniquely substituted phenyl sulfone into a series of biphenyl imidazole liver X receptor (LXR) agonists afforded a dramatic potency improvement for induction of ATP binding cassette transporters, ABCA1 and ABCG1, in human whole blood. The agonist series demonstrated robust LXRß activity (>70%) with low partial LXRα agonist activity (<25%) in cell assays, providing a window between desired blood cell ABCG1 gene induction in cynomolgus monkeys and modest elevation of plasma triglycerides for agonist 15. The addition of polarity to the phenyl sulfone also reduced binding to the plasma protein, human α-1-acid glycoprotein. Agonist 15 was selected for clinical development based on the favorable combination of in vitro properties, excellent pharmacokinetic parameters, and a favorable lipid profile.

13.
J Org Chem ; 69(2): 327-34, 2004 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-14725443

RESUMO

A class of zinc reagents (RXZnCH(2)Y) generated with an appropriate organozinc is very effective for the cyclopropanation of olefins. The reactivity and selectivity of these reagents can be regulated by tuning the electronic and steric nature of the RX group on Zn. A reasonable level of enantioselectivity was obtained for the cyclopropanation of unfunctionalized olefins when a chiral (iodomethyl)zinc species was used, providing a valuable approach for the asymmetric cyclopropanation of unfunctionalized olefins.

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