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1.
Molecules ; 28(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36677588

RESUMO

Favipiravir (FAV) has become a promising antiviral agent for the treatment of COVID-19. Herein, a green, fast, high-sample-throughput, non-instrumental, and affordable analytical method is proposed based on surfactant-assisted dispersive liquid-liquid microextraction (SA-DLLME) combined with thin-layer chromatography-digital image colourimetry (TLC-DIC) for determining favipiravir in biological and pharmaceutical samples. Triton X-100 and dichloromethane (DCM) were used as the disperser and extraction solvents, respectively. The extract obtained after DLLME procedure was spotted on a TLC plate and allowed to develop with a mobile phase of chloroform:methanol (8:2, v/v). The developed plate was photographed using a smartphone under UV irradiation at 254 nm. The quantification of FAV was performed by analysing the digital images' spots with open-source ImageJ software. Multivariate optimisation using Plackett-Burman design (PBD) and central composite design (CCD) was performed for the screening and optimisation of significant factors. Under the optimised conditions, the method was found to be linear, ranging from 5 to 100 µg/spot, with a correlation coefficient (R2) ranging from 0.991 to 0.994. The limit of detection (LOD) and limit of quantification (LOQ) were in the ranges of 1.2-1.5 µg/spot and 3.96-4.29 µg/spot, respectively. The developed approach was successfully applied for the determination of FAV in biological (i.e., human urine and plasma) and pharmaceutical samples. The results obtained using the proposed methodology were compared to those obtained using HPLC-UV analysis and found to be in close agreement with one another. Additionally, the green character of the developed method with previously reported protocols was evaluated using the ComplexGAPI, AGREE, and Eco-Scale greenness assessment tools. The proposed method is green in nature and does not require any sophisticated high-end analytical instruments, and it can therefore be routinely applied for the analysis of FAV in various resource-limited laboratories during the COVID-19 pandemic.


Assuntos
COVID-19 , Microextração em Fase Líquida , Surfactantes Pulmonares , Humanos , Tensoativos , Colorimetria , Cromatografia em Camada Fina , Microextração em Fase Líquida/métodos , Smartphone , Pandemias , Solventes , Cromatografia Líquida de Alta Pressão , Lipoproteínas , Preparações Farmacêuticas , Limite de Detecção
2.
Molecules ; 27(21)2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36364020

RESUMO

Fabric phase sorptive extraction (FPSE) has become a popular sorptive-based microextraction technique for the rapid analysis of a wide variety of analytes in complex matrices. The present study describes a simple and green analytical protocol based on in-matrix methyl chloroformate (MCF) derivatization of non-steroidal anti-inflammatory (NSAID) drugs in urine samples followed by FPSE and gas chromatography-mass spectrometry (GC-MS) analysis. Use of MCF as derivatizing reagent saves substantial amounts of time, reagent and energy, and can be directly performed in aqueous samples without any sample pre-treatment. The derivatized analytes were extracted using sol−gel Carbowax 20M coated FPSE membrane and eluted in 0.5 mL of MeOH for GC-MS analysis. A chemometric design of experiment-based approach was utilized comprising a Placket−Burman design (PBD) and central composite design (CCD) for screening and optimization of significant variables of derivatization and FPSE protocol, respectively. Under optimized conditions, the proposed FPSE-GC-MS method exhibited good linearity in the range of 0.1−10 µg mL−1 with coefficients of determination (R2) in the range of 0.998−0.999. The intra-day and inter-day precisions for the proposed method were lower than <7% and <10%, respectively. The developed method has been successfully applied to the determination of NSAIDs in urine samples of patients under their medication. Finally, the green character of the proposed method was evaluated using ComplexGAPI tool. The proposed method will pave the way for simper analysis of polar drugs by FPSE-GC-MS.


Assuntos
Anti-Inflamatórios não Esteroides , Poluentes Químicos da Água , Humanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Anti-Inflamatórios não Esteroides/análise , Poluentes Químicos da Água/análise , Água/química
3.
Anal Bioanal Chem ; 412(17): 4101-4112, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32306070

RESUMO

Here, different monoclonal antibodies (mAb1, mAb2 and mAb3) of Ebola virus were screened in a real-time and label-free manner using surface plasmon resonance (SPR) to select an appropriate antibody for biosensor applications against a biological warfare agent. For this purpose, a gold SPR chip was modified with 4-mercaptobenzoic acid (4-MBA), and modification was confirmed by FTIR-ATR and EIS. The 4-MBA-modified gold SPR chip was used for immobilization of the recombinant nucleoprotein of Ebola (EBOV-rNP), and the interactions of mAb1, mAb2 and mAb3 were then investigated to determine the best mAb based on the affinity constant (KD), expressed as equilibrium dissociation constant. KD values of 809 nM, 350 pM and 52 pM were found for the interaction of mAb1, mAb2 and mAb3 of Ebola with the immobilized EBOV-rNP, respectively, thus reflecting the high affinity of mAb3. This was confirmed by ELISA results. The thermodynamic parameters (ΔG, ΔH and ΔS) for the interaction between mAb3 and EBOV-rNP were also determined, which revealed that the interaction was spontaneous, endothermic and driven by entropy. The SPR limit of detection of EBOV-rNP with mAb3 was 0.5 pg ml-1, showing mAb3 to be the best high-affinity antibody in our study. This study has opened up new possibilities for SPR screening of different monoclonal antibodies of BWA through the convergence of materials science and optical techniques.


Assuntos
Ebolavirus/isolamento & purificação , Doença pelo Vírus Ebola/virologia , Ressonância de Plasmônio de Superfície/métodos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Afinidade de Anticorpos , Benzoatos/química , Ebolavirus/imunologia , Doença pelo Vírus Ebola/diagnóstico , Humanos , Compostos de Sulfidrila/química , Termodinâmica
5.
JAMA ; 331(9): 727-728, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315157

RESUMO

This Viewpoint discusses the ABIM's continuing efforts to innovate and streamline maintenance of certification, including the recently launched Longitudinal Knowledge Assessment (LKA), to better accommodate physicians' schedules and desires for flexibility.


Assuntos
Certificação , Competência Clínica , Médicos , Humanos , Certificação/métodos , Certificação/normas , Certificação/tendências , Competência Clínica/normas , Educação Médica Continuada/normas , Médicos/normas , Estados Unidos
6.
BMC Bioinformatics ; 19(Suppl 18): 491, 2018 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-30577736

RESUMO

BACKGROUND: Current multi-petaflop supercomputers are powerful systems, but present challenges when faced with problems requiring large machine learning workflows. Complex algorithms running at system scale, often with different patterns that require disparate software packages and complex data flows cause difficulties in assembling and managing large experiments on these machines. RESULTS: This paper presents a workflow system that makes progress on scaling machine learning ensembles, specifically in this first release, ensembles of deep neural networks that address problems in cancer research across the atomistic, molecular and population scales. The initial release of the application framework that we call CANDLE/Supervisor addresses the problem of hyper-parameter exploration of deep neural networks. CONCLUSIONS: Initial results demonstrating CANDLE on DOE systems at ORNL, ANL and NERSC (Titan, Theta and Cori, respectively) demonstrate both scaling and multi-platform execution.


Assuntos
Detecção Precoce de Câncer/métodos , Aprendizado de Máquina/tendências , Neoplasias/diagnóstico , Humanos , Neoplasias/patologia , Redes Neurais de Computação , Fluxo de Trabalho
7.
Mikrochim Acta ; 185(2): 89, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29594390

RESUMO

This review (with 210 references) summarizes recent developments in the design of voltammetric chemical sensors and biosensors based on the use of carbon nanomaterials (CNMs). It is divided into subsections starting with an introduction into the field and a description of its current state. This is followed by a large section on various types of voltammetric sensors and biosensors using CNMs with subsections on sensors based on the use of carbon nanotubes, graphene, graphene oxides, graphene nanoribbons, fullerenes, ionic liquid composites with CNMs, carbon nanohorns, diamond nanoparticles, carbon dots, carbon nanofibers and mesoporous carbon. The third section gives conclusion and an outlook. Tables are presented on the application of such sensors to voltammetric detection of neurotransmitters, metabolites, dietary minerals, proteins, heavy metals, gaseous molecules, pharmaceuticals, environmental pollutants, food, beverages, cosmetics, commercial goods and drugs of abuse. The authors also describe advanced approaches for the fabrication of robust functional carbon nano(bio)sensors for voltammetric quantification of multiple targets. Graphical Abstract Featuring execellent electrical, catalytic and surface properies, CNMs have gained enormous attention for designing voltammetric sensors and biosensors. Functionalized CNM-modified electrode interfaces have demonstrated their prominent role in biological, environmental, pharmaceutical, chemical, food and industrial analysis.

9.
PLoS Genet ; 10(2): e1004201, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24586211

RESUMO

Plasma cholesterol lowering (PCL) slows and sometimes prevents progression of atherosclerosis and may even lead to regression. Little is known about how molecular processes in the atherosclerotic arterial wall respond to PCL and modify responses to atherosclerosis regression. We studied atherosclerosis regression and global gene expression responses to PCL (≥80%) and to atherosclerosis regression itself in early, mature, and advanced lesions. In atherosclerotic aortic wall from Ldlr(-/-)Apob (100/100) Mttp (flox/flox)Mx1-Cre mice, atherosclerosis regressed after PCL regardless of lesion stage. However, near-complete regression was observed only in mice with early lesions; mice with mature and advanced lesions were left with regression-resistant, relatively unstable plaque remnants. Atherosclerosis genes responding to PCL before regression, unlike those responding to the regression itself, were enriched in inherited risk for coronary artery disease and myocardial infarction, indicating causality. Inference of transcription factor (TF) regulatory networks of these PCL-responsive gene sets revealed largely different networks in early, mature, and advanced lesions. In early lesions, PPARG was identified as a specific master regulator of the PCL-responsive atherosclerosis TF-regulatory network, whereas in mature and advanced lesions, the specific master regulators were MLL5 and SRSF10/XRN2, respectively. In a THP-1 foam cell model of atherosclerosis regression, siRNA targeting of these master regulators activated the time-point-specific TF-regulatory networks and altered the accumulation of cholesterol esters. We conclude that PCL leads to complete atherosclerosis regression only in mice with early lesions. Identified master regulators and related PCL-responsive TF-regulatory networks will be interesting targets to enhance PCL-mediated regression of mature and advanced atherosclerotic lesions.


Assuntos
Aorta/metabolismo , Aterosclerose/sangue , Colesterol/sangue , Receptores de LDL/genética , Animais , Aorta/efeitos dos fármacos , Apolipoproteínas B/genética , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/biossíntese , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Camundongos , Camundongos Transgênicos , Proteínas Nucleares/biossíntese , Ribonucleoproteínas/biossíntese , Fatores de Processamento de Serina-Arginina
11.
Phys Rev Lett ; 116(15): 151103, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127952

RESUMO

Scalar-tensor theories of gravity can lead to modifications of the gravitational force inside astrophysical objects. We exhibit that compact stars such as white dwarfs provide a unique setup to test beyond Horndeski theories of G^{3} type. We obtain stringent and independent constraints on the parameter ϒ characterizing the deviations from Newtonian gravity using the mass-radius relation, the Chandrasekhar mass limit, and the maximal rotational frequency of white dwarfs. We find that white dwarfs impose stronger constraints on ϒ than red and brown dwarfs.

14.
Arterioscler Thromb Vasc Biol ; 34(9): 2068-77, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24925974

RESUMO

OBJECTIVE: Using a multi-tissue, genome-wide gene expression approach, we recently identified a gene module linked to the extent of human atherosclerosis. This atherosclerosis module was enriched with inherited risk for coronary and carotid artery disease (CAD) and overlapped with genes in the transendothelial migration of leukocyte (TEML) pathway. Among the atherosclerosis module genes, the transcription cofactor Lim domain binding 2 (LDB2) was the most connected in a CAD vascular wall regulatory gene network. Here, we used human genomics and atherosclerosis-prone mice to evaluate the possible role of LDB2 in TEML and atherosclerosis. APPROACH AND RESULTS: mRNA profiles generated from blood macrophages in patients with CAD were used to infer transcription factor regulatory gene networks; Ldlr(-/-)Apob(100/100) mice were used to study the effects of Ldb2 deficiency on TEML activity and atherogenesis. LDB2 was the most connected gene in a transcription factor regulatory network inferred from TEML and atherosclerosis module genes in CAD macrophages. In Ldlr(-/-)Apob(100/100) mice, loss of Ldb2 increased atherosclerotic lesion size ≈2-fold and decreased plaque stability. The exacerbated atherosclerosis was caused by increased TEML activity, as demonstrated in air-pouch and retinal vasculature models in vivo, by ex vivo perfusion of primary leukocytes, and by leukocyte migration in vitro. In THP1 cells, migration was increased by overexpression and decreased by small interfering RNA inhibition of LDB2. A functional LDB2 variant (rs10939673) was associated with the risk and extent of CAD across several cohorts. CONCLUSIONS: As a key driver of the TEML pathway in CAD macrophages, LDB2 is a novel candidate to target CAD by inhibiting the overall activity of TEML.


Assuntos
Aterosclerose/fisiopatologia , Doenças das Artérias Carótidas/patologia , Quimiotaxia de Leucócito/fisiologia , Doença da Artéria Coronariana/patologia , Proteínas com Domínio LIM/fisiologia , Fatores de Transcrição/fisiologia , Migração Transendotelial e Transepitelial/fisiologia , Animais , Apolipoproteína B-100/genética , Doenças das Artérias Carótidas/genética , Linhagem Celular Tumoral , Quimiocina CCL2/farmacologia , Doença da Artéria Coronariana/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Proteínas com Domínio LIM/deficiência , Proteínas com Domínio LIM/genética , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , RNA Mensageiro/biossíntese , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Migração Transendotelial e Transepitelial/genética
19.
Helicobacter ; 19(5): 349-55, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24826984

RESUMO

BACKGROUND: Lymphocytic gastritis (LG), characterized by marked intra-epithelial lymphocytosis in the gastric mucosa, has been frequently associated with both celiac disease (CD) and H. pylori gastritis. The aim of this study was to review and correlate the morphology of LG with the presence of CD and H. pylori. MATERIALS AND METHODS: Gastric biopsies diagnosed with LG from 1/1/2006 to 8/1/2013 at our institution and corresponding small bowel biopsies, when available, were reviewed for verification of the diagnosis and to assess for the presence of H. pylori and CD. Immunohistochemical (IHC) staining for H. pylori was performed on all gastric biopsies. Demographic, clinical, and laboratory data were obtained from the medical record. RESULTS: Fifty-four of the 56 cases that met inclusion criteria demonstrated significant intra-epithelial lymphocytosis as the predominant histologic abnormality; however, none were associated with H. pylori infection by IHC staining. Two cases that also showed a prominent intra-epithelial and lamina propria neutrophilic infiltrate were both positive for H. pylori and were excluded from further study. Of the 36 small bowel biopsies available, 19 (53%) showed changes in CD. CONCLUSIONS: LG is not a distinct clinicopathologic entity, but a morphologic pattern of gastric injury that can be secondary to a variety of underlying etiologies. When restricted to cases with lymphocytosis alone, LG is strongly associated with CD and not with active H. pylori infection. However, cases that also show significant neutrophilic infiltrate should be regarded as "active chronic gastritis" and are often associated with H. pylori infection. A morphologic diagnosis of LG should prompt clinical and serologic workup to exclude underlying CD.


Assuntos
Doença Celíaca/complicações , Mucosa Gástrica/patologia , Gastrite/etiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/fisiologia , Linfocitose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Doença Celíaca/patologia , Feminino , Gastrite/complicações , Gastrite/patologia , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Humanos , Linfocitose/complicações , Linfocitose/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
20.
BMC Ophthalmol ; 14: 152, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25434291

RESUMO

BACKGROUND: Diabetes mellitus is rapidly increasing in the Indian population. The purpose of this study was to identify changes in the retinal vasculature of diabetic people, ahead of visual impairments. Grayscale Fractal Dimension (FD) analysis of retinal images was performed on people with type 2 diabetes from an Indian population. METHODS: A cross-sectional study comprising 189 Optic Disc (OD) centred retinal images of healthy and diabetic individuals aged 14 to 73 years was conducted. Grayscale Box Counting FD of these retinal photographs was measured without manual supervision. Statistical analysis was conducted to determine the difference in the FD between diabetic and healthy (non-diabetic) people. RESULTS: The results show that grayscale FD values for diabetic cases are higher compared to controls, irrespective of the gender. It was also observed that FD was higher for male compared with females. CONCLUSIONS: There is difference in the grayscale fractal dimension of retinal vasculature of diabetic patients and healthy subjects, even when there is no reported retinopathy.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Retinopatia Diabética/fisiopatologia , Fractais , Vasos Retinianos/patologia , Adolescente , Adulto , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Estudos Transversais , Retinopatia Diabética/diagnóstico , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Fotografação/métodos , Medição de Risco , Adulto Jovem
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