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1.
Sensors (Basel) ; 23(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37430625

RESUMEN

The demand for deep learning frameworks capable of running in edge computing environments is rapidly increasing due to the exponential growth of data volume and the need for real-time processing. However, edge computing environments often have limited resources, necessitating the distribution of deep learning models. Distributing deep learning models can be challenging as it requires specifying the resource type for each process and ensuring that the models are lightweight without performance degradation. To address this issue, we propose the Microservice Deep-learning Edge Detection (MDED) framework, designed for easy deployment and distributed processing in edge computing environments. The MDED framework leverages Docker-based containers and Kubernetes orchestration to obtain a pedestrian-detection deep learning model with a speed of up to 19 FPS, satisfying the semi-real-time condition. The framework employs an ensemble of high-level feature-specific networks (HFN) and low-level feature-specific networks (LFN) trained on the MOT17Det dataset, achieving an accuracy improvement of up to AP50 and AP0.18 on MOT20Det data.

2.
Anal Chem ; 94(2): 1441-1446, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34949084

RESUMEN

The determination of the enantiomeric excess and absolute configuration of chiral compounds is indispensable in synthetic, pharmaceutical, and biological chemistry. In this article, we describe an efficient 19F nuclear magnetic resonance (NMR)-based analytical protocol for determining the enantiomeric excess and absolute configuration of in situ fluorine-labeled amines and alcohols. 2-Fluorobenzoylation was used to convert analytes to fluorinated amides or esters. The resulting F-labeled analytes were mixed with a cationic cobalt(III) complex, [Co]BArF, resulting in clean baseline peak separations of analyte enantiomers in 19F{1H} NMR spectra. The measured ΔδRS signs were unambiguously used to correlate the absolute configurations of amines, amino alcohols, and alcohols. Moreover, the structure-dependent 19F{1H} NMR signals enabled absolute configuration determination by analyzing the relative chemical shifts of enantiopure analyte samples with [Co]BArF and ent-[Co]BArF.


Asunto(s)
Alcoholes , Aminas , Alcoholes/química , Aminas/química , Flúor , Espectroscopía de Resonancia Magnética/métodos , Estereoisomerismo
3.
Nat Methods ; 13(1): 87-93, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26524239

RESUMEN

The diverse progenitors that give rise to the human neocortex have been difficult to characterize because progenitors, particularly radial glia (RG), are rare and are defined by a combination of intracellular markers, position and morphology. To circumvent these problems, we developed Fixed and Recovered Intact Single-cell RNA (FRISCR), a method for profiling the transcriptomes of individual fixed, stained and sorted cells. Using FRISCR, we profiled primary human RG that constitute only 1% of the midgestation cortex and classified them as ventricular zone-enriched RG (vRG) that express ANXA1 and CRYAB, and outer subventricular zone-localized RG (oRG) that express HOPX. Our study identified vRG and oRG markers and molecular profiles, an essential step for understanding human neocortical progenitor development. FRISCR allows targeted single-cell profiling of any tissues that lack live-cell markers.


Asunto(s)
Encéfalo/citología , Neuroglía/citología , Transcriptoma , Humanos , Análisis de la Célula Individual
4.
J Org Chem ; 83(23): 14300-14306, 2018 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-30398053

RESUMEN

The favorable effect of 2-hydroxyphenyl groups for ketimine formation with benzophenone was demonstrated by combining computational and experimental studies. Although direct imine formation between benzophenone and primary amines is challenging, 2-hydroxybenzophenone or 2,2'-dihydroxybenzophenone was readily used for ketimine formation with various primary alkyl amines and anilines. Measured activation parameters and calculated energy profiles indicated that the 2-hydroxyphenyl group can lower both activation barriers and equilibrium energies by establishing intramolecular and intermolecular hydrogen-bonding interactions.

5.
J Sep Sci ; 36(14): 2306-14, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23686964

RESUMEN

A simple, robust, and rapid LC-MS/MS method has been developed and validated for the simultaneous quantitation of clopidogrel and its active metabolite (AM) in human plasma. Tris(2-carboxyethyl)phosphine (TCEP) was used as a reducing agent to detect the AM as a disulfide-bonded complex with plasma proteins. Mixtures of TCEP and human plasma were deproteinized with acetonitrile containing 10 ng/mL of clopidogrel-d4 as an internal standard (IS). The mixtures were separated on a C18 RP column with an isocratic mobile phase consisting of 0.1% formic acid in acetonitrile and water (90:10, v/v) at a flow rate of 0.3 mL/min. Detection and quantification were performed using ESI-MS. The detector was operated in selected reaction-monitoring mode at m/z 322.0→211.9 for clopidogrel, m/z 356.1→155.2 for the AM, and m/z 326.0→216.0 for the IS. The linear dynamic range for clopidogrel and its AM were 0.05-20 and 0.5-200 ng/mL, respectively, with correlation coefficients (r) greater than 0.9976. Precision, both intra- and interday, was less than 8.26% with an accuracy of 87.6-106%. The validated method was successfully applied to simultaneously analyze clinical samples for clopidogrel and its AM.


Asunto(s)
Cromatografía Liquida/métodos , Compuestos de Sulfhidrilo/sangre , Espectrometría de Masas en Tándem/métodos , Ticlopidina/análogos & derivados , Clopidogrel , Humanos , Oxidación-Reducción , Fosfinas/química , Compuestos de Sulfhidrilo/metabolismo , Ticlopidina/sangre , Ticlopidina/metabolismo
6.
Org Lett ; 25(12): 2036-2040, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36926952

RESUMEN

Determining the chirality of phosphoric acids can be a challenging task. In this study, we present a novel approach for the chiral recognition of phosphates using cationic octahedral cobalt complexes. By utilizing 31P NMR spectroscopy, we are able to accurately measure the enantiopurities of chiral phosphoric acids after forming ion pairs with the cobalt complexes. We have successfully applied this method to a variety of chiral phosphoric acids derived from BINOL, H8-BINOL, SPINOL, VAPOL, and VANOL compounds, as well as ATP, and were able to efficiently resolve them in 31P{1H} NMR spectra. Furthermore, we were able to achieve an optical resolution of a phosphoric acid with an enantiomeric excess of greater than 99%.

7.
Nat Commun ; 13(1): 5427, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36109497

RESUMEN

Neurons born in the embryo can undergo a protracted period of maturation lasting well into postnatal life. How gene expression changes are regulated during maturation and whether they can be recapitulated in cultured neurons remains poorly understood. Here, we show that mouse motor neurons exhibit pervasive changes in gene expression and accessibility of associated regulatory regions from embryonic till juvenile age. While motifs of selector transcription factors, ISL1 and LHX3, are enriched in nascent regulatory regions, motifs of NFI factors, activity-dependent factors, and hormone receptors become more prominent in maturation-dependent enhancers. Notably, stem cell-derived motor neurons recapitulate ~40% of the maturation expression program in vitro, with neural activity playing only a modest role as a late-stage modulator. Thus, the genetic maturation program consists of a core hardwired subprogram that is correctly executed in vitro and an extrinsically-controlled subprogram that is dependent on the in vivo context of the maturing organism.


Asunto(s)
Neuronas Motoras , Neurogénesis , Animales , Hormonas/metabolismo , Proteínas con Homeodominio LIM/genética , Proteínas con Homeodominio LIM/metabolismo , Ratones , Neuronas Motoras/metabolismo , Neurogénesis/genética , Factores de Transcripción/metabolismo , Transcripción Genética
8.
Neuron ; 110(1): 70-85.e6, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34727520

RESUMEN

Proper assembly and function of the nervous system requires the generation of a uniquely diverse population of neurons expressing a cell-type-specific combination of effector genes that collectively define neuronal morphology, connectivity, and function. How countless partially overlapping but cell-type-specific patterns of gene expression are controlled at the genomic level remains poorly understood. Here we show that neuronal genes are associated with highly complex gene regulatory systems composed of independent cell-type- and cell-stage-specific regulatory elements that reside in expanded non-coding genomic domains. Mapping enhancer-promoter interactions revealed that motor neuron enhancers are broadly distributed across the large chromatin domains. This distributed regulatory architecture is not a unique property of motor neurons but is employed throughout the nervous system. The number of regulatory elements increased dramatically during the transition from invertebrates to vertebrates, suggesting that acquisition of new enhancers might be a fundamental process underlying the evolutionary increase in cellular complexity.


Asunto(s)
Elementos de Facilitación Genéticos , Vertebrados , Animales , Cromatina/genética , Cromatina/metabolismo , Elementos de Facilitación Genéticos/genética , Genómica , Neuronas Motoras/metabolismo , Vertebrados/genética
9.
Org Lett ; 23(20): 7829-7833, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34559535

RESUMEN

Herein, efficient chiral recognition of phosphine oxides with octahedral indium complexes was demonstrated. Direct chiral analysis of in situ-prepared phosphine oxides formed using phosphines and hydrogen peroxide was conducted effectively via 31P nuclear magnetic resonance spectroscopy. Sufficient peak resolution of chiral phosphines was obtained consistently, thereby enabling the reliable determination of absolute chirality. Rational 1:1 binding models based on experiments and density functional theory calculations have been proposed.

10.
Org Lett ; 22(11): 4185-4189, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32396379

RESUMEN

We report a newly prepared cationic cobalt(III) complex as a general and efficient chiral solvating agent that discriminates carbonyl compounds including esters, amides, ketones, and aldehydes. This cobalt(III) complex was further utilized to directly analyze both the conversion and the enantiomeric excess at once in the asymmetric fluorination.

11.
Org Lett ; 22(20): 7804-7808, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-32910666

RESUMEN

We have demonstrated the efficient chiral analysis of fluorine-containing compounds by 19F NMR spectroscopy. The highly sensitive fluorine nucleus allowed chiral analysis of complex mixtures and even asymmetric reaction mixtures of multisubstrates. A single 19F NMR experiment was sufficient to determine the enantiomeric excesses and yields of the five products simultaneously.

12.
iScience ; 19: 425-435, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31421597

RESUMEN

In situ, direct 1H NMR chiral analysis by using chiral solvating agents is a convenient and efficient analytical technique. Here we developed a Ga-based chiral anionic metal complex for 1H NMR chiral analysis of alcohols. Utilizing the optimal pKa value, the Ga complex was able to differentiate 1H NMR signals of each (R)- and (S)-enantiomer of alcohols, measured at room temperature. This direct 1H NMR chiral analysis of alcohols was used to rapidly determine enantiomeric excess and conversion in a kinetic resolution and an asymmetric synthesis.

13.
Chem Commun (Camb) ; 54(50): 6804-6807, 2018 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-29546905

RESUMEN

A chiral aluminum solvating agent (CASA) was demonstrated to be a general and efficient reagent for 1H NMR chiral analysis of alcohols. The sodium salt of the CASA (CASA-Na) showed a complete baseline peak separation of the hydroxyl group for various chiral alcohols including primary, secondary, and tertiary alcohols with alkyl and aryl substituents in CD3CN. Due to the weak intermolecular interaction, 1H NMR measurement at low temperature (-40 to 10 °C) was required.

14.
Elife ; 62017 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-28296635

RESUMEN

The complexity of gene regulatory networks that lead multipotent cells to acquire different cell fates makes a quantitative understanding of differentiation challenging. Using a statistical framework to analyze single-cell transcriptomics data, we infer the gene expression dynamics of early mouse embryonic stem (mES) cell differentiation, uncovering discrete transitions across nine cell states. We validate the predicted transitions across discrete states using flow cytometry. Moreover, using live-cell microscopy, we show that individual cells undergo abrupt transitions from a naïve to primed pluripotent state. Using the inferred discrete cell states to build a probabilistic model for the underlying gene regulatory network, we further predict and experimentally verify that these states have unique response to perturbations, thus defining them functionally. Our study provides a framework to infer the dynamics of differentiation from single cell transcriptomics data and to build predictive models of the gene regulatory networks that drive the sequence of cell fate decisions during development.


Asunto(s)
Diferenciación Celular , Células Madre Embrionarias/fisiología , Animales , Citometría de Flujo , Perfilación de la Expresión Génica , Ratones , Análisis de la Célula Individual
15.
J Pharm Biomed Anal ; 55(5): 1083-8, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21466936

RESUMEN

A sensitive liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed for a novel dipeptidyl peptidase IV agonist (DDP-IV) agonist, KR-66223, in rat plasma. It involves liquid-liquid extraction (LLE) followed by HPLC separation and electrospray ionization tandem mass spectrometry. KR-66223 and imipramine (IS) was separated on Gemini-NX C18 column with mixture of acetonitrile-ammonium formate (10mM) (90:10, v/v) as mobile phase. The ion transitions monitored were m/z 553.2→206.2 for KR-66223, m/z 281.3→86.1 for imipramine in multiple reaction monitoring (MRM) mode. The linear ranges of the assay were 0.003-10µg/ml with a correlation coefficient (R(2)) greater than 0.99 and the lower limit of quantification was 3ng/ml. The average recovery was 78.9% and 87.1% from rat plasma for KR-66223 and imipramine, respectively. The coefficients of variation of intra- and inter-assay were 3.9-14.4% and the relative error was 0.8-11.5%. The method was validated and successfully applied to the pharmacokinetic study of KR-66223 in rat.


Asunto(s)
Aminobutiratos/sangre , Cromatografía Liquida/métodos , Dipeptidil Peptidasa 4/agonistas , Espectrometría de Masas en Tándem/métodos , Tiazolidinas/química , Acetonitrilos/química , Aminobutiratos/química , Animales , Área Bajo la Curva , Proteínas Sanguíneas/química , Calibración , Formiatos/química , Imipramina/química , Masculino , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Tiazolidinas/sangre , Valina/análogos & derivados
16.
PLoS One ; 6(3): e18168, 2011 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-21464945

RESUMEN

Increasing evidence that decreased bone density and increased rates of bone fracture are associated with abnormal metabolic states such as hyperglycemia and insulin resistance indicates that diabetes is a risk factor for osteoporosis. In this study, we observed that TallyHo/JngJ (TH) mice, a polygenic model of type II diabetes, spontaneously developed bone deformities with osteoporotic features. Female and male TH mice significantly gained more body weight than control C57BL/6 mice upon aging. Interestingly, bone density was considerably decreased in male TH mice, which displayed hyperglycemia. The osteoblast-specific bone forming markers osteocalcin and osteoprotegerin were decreased in TH mice, whereas osteoclast-driven bone resorption markers such as IL-6 and RANKL were significantly elevated in the bone marrow and blood of TH mice. In addition, RANKL expression was prominently increased in CD4+ T cells of TH mice upon T cell receptor stimulation, which was in accordance with enhanced IL-17 production. IL-17 production in CD4+ T cells was directly promoted by treatment with leptin while IFN-γ production was not. Moreover, blockade of IFN-γ further increased RANKL expression and IL-17 production in TH-CD4+ T cells. In addition, the osteoporotic phenotype of TH mice was improved by treatment with alendronate. These results strongly indicate that increased leptin in TH mice may act in conjunction with IL-6 to preferentially stimulate IL-17 production in CD4+ T cells and induce RANKL-mediated osteoclastogenesis. Accordingly, we propose that TH mice could constitute a beneficial model for osteoporosis.


Asunto(s)
Resorción Ósea/metabolismo , Linfocitos T CD4-Positivos/metabolismo , Interleucina-17/biosíntesis , Ligando RANK/metabolismo , Alendronato/farmacología , Animales , Biomarcadores/metabolismo , Densidad Ósea/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Médula Ósea/metabolismo , Resorción Ósea/sangre , Resorción Ósea/fisiopatología , Linfocitos T CD4-Positivos/efectos de los fármacos , Femenino , Interferón gamma/sangre , Interleucina-6/sangre , Leptina/sangre , Leptina/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Osteoblastos/efectos de los fármacos , Osteoblastos/metabolismo , Osteoblastos/patología , Osteocalcina/sangre , Osteogénesis/efectos de los fármacos , Testosterona/farmacología
17.
Science ; 327(5963): 348-51, 2010 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-20075256

RESUMEN

A major obstacle for the discovery of psychoactive drugs is the inability to predict how small molecules will alter complex behaviors. We report the development and application of a high-throughput, quantitative screen for drugs that alter the behavior of larval zebrafish. We found that the multidimensional nature of observed phenotypes enabled the hierarchical clustering of molecules according to shared behaviors. Behavioral profiling revealed conserved functions of psychotropic molecules and predicted the mechanisms of action of poorly characterized compounds. In addition, behavioral profiling implicated new factors such as ether-a-go-go-related gene (ERG) potassium channels and immunomodulators in the control of rest and locomotor activity. These results demonstrate the power of high-throughput behavioral profiling in zebrafish to discover and characterize psychotropic drugs and to dissect the pharmacology of complex behaviors.


Asunto(s)
Conducta Animal/efectos de los fármacos , Descubrimiento de Drogas/métodos , Ensayos Analíticos de Alto Rendimiento , Actividad Motora/efectos de los fármacos , Psicotrópicos/farmacología , Vigilia/efectos de los fármacos , Pez Cebra/fisiología , Algoritmos , Animales , Antiinflamatorios/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/metabolismo , Análisis por Conglomerados , Citocinas/metabolismo , Canales de Potasio Éter-A-Go-Go/antagonistas & inhibidores , Canales de Potasio Éter-A-Go-Go/fisiología , Larva/efectos de los fármacos , Larva/fisiología , Bloqueadores de los Canales de Potasio/farmacología , Descanso , Transducción de Señal , Sueño/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas , Pez Cebra/crecimiento & desarrollo , Proteínas de Pez Cebra/metabolismo
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