scholarly journals SEEDING to enable sensitive electrochemical detection of biomarkers in undiluted biological samples

2021 ◽  
Author(s):  
Jonathan Sabaté del Río ◽  
Hyun-Kyung Woo ◽  
Juhee Park ◽  
Hong Koo Ha ◽  
Jae-Ryong Kim ◽  
...  
Keyword(s):  
Small Molecules ◽  
Biological Fluids ◽  
Critical Role ◽  
Direct Analysis ◽  
Porous Surfaces ◽  
Plasma And Urine Samples ◽  
Overall Performance ◽  
Detection Of Biomarkers ◽  
Diffusion Profiles ◽  
Surfactant Assisted

Abstract The interface between an electrode and a liquid plays a critical role in the overall performance of electrochemical biosensors. Surface morphology and roughness affect key parameters, such as the active area, diffusion profiles, and apparent electron transfer kinetics, whereas porosity may hinder the diffusion of fouling proteins. However, there is no simple and rapid method compatible with photolithographic electrodes to generate both nanostructured and porous surfaces. Herein, we demonstrate the interplay between the preferential etching of chloride and surfactant-assisted anisotropic gold reduction to create homogeneous, nanostructured, and nanoporous substrates on photolithographic gold electrodes within a minute and without using templates. We coined this process, SEEDING, that is, Surfactant-based Electrochemical Etch-Deposit Interplay for Nanostructure/Nanopore Growth. SEEDING on electrodes enhanced the sensitivity and anti-biofouling capabilities, enabling direct analysis of small molecules, proteins, and cancer-derived extracellular vesicles in complex biological fluids such as undiluted plasma and urine samples.

Salivary mir-27b Expression in Oral Lichen Planus Patients: A Series of Cases and a Narrative Review of Literature

2020 ◽  
Vol 19 (31) ◽  
pp. 2816-2823 ◽  
Author(s):  
Dario Di Stasio ◽  
Laura Mosca ◽  
Alberta Lucchese ◽  
Donatella Delle Cave ◽  
Hiromichi Kawasaki ◽  
...  
Keyword(s):  
Lichen Planus ◽  
Oral Lichen Planus ◽  
Inflammatory Diseases ◽  
Biological Fluids ◽  
Critical Role ◽  
Invasive Procedure ◽  
Control Group ◽  
Study Group ◽  
Immune Functions ◽  
Oral Lichen

Background: microRNAs play a critical role in auto-immunity, cell proliferation, differentiation and cell death. miRNAs are present in all biological fluids, and their expression is essential in maintaining regular immune functions and preventing autoimmunity, whereas miRNA dysregulation may be associated with the pathogenesis of autoimmune and inflammatory diseases. Oral lichen planus (OLP) is an inflammatory disease mediated by cytotoxic T cells attack against epithelial cells. The present study aims to perform a specific microRNA expression profile through the analysis of saliva in this disease. Methods: The study group was formed by five patients (mean age 62.8±1.98 years; 3 females/2 males) affected by oral lichen planus and control group by five healthy subjects (mean age 59.8 years±2.3; 3 females/ 2 males); using a low-density microarray analysis, we recorded a total of 98 differentially expressed miRNAs in the saliva of patients with oral lichen planus compared to the control group. The validation was performed for miR-27b with qRT-PCR in all saliva samples of oral lichen planus group. Results: 89 miRNAs were up-regulated and nine down-regulated. In details, levels of miR-21, miR- 125b, miR-203 and miR15b were increased (p<0.001) in study group while levels of miR-27b were about 3.0-fold decreased compared to controls (p<0.001) of miR-27b expression in OLP saliva. QRTPCR validation confirmed the down regulation of miR-27b in all saliva samples. Conclusions: Collecting saliva samples is a non-invasive procedure and is well accepted by all patients. microRNAs can be readily isolated and identified and can represent useful biomarkers of OLP.

scholarly journals STEM-20. A CANCER STEM CELL-SELECTIVE APOPTOSIS-INDUCING SMALL MOLECULE FOR THE TREATMENT OF GBM

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii200-ii200
Author(s):  
Stephen Skirboll ◽  
Natasha Lucki ◽  
Genaro Villa ◽  
Naja Vergani ◽  
Michael Bollong ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cancer Stem Cells ◽  
Small Molecules ◽  
Small Molecule ◽  
Large Scale ◽  
Critical Role ◽  
Tumor Formation ◽  
Cell Type ◽  
Caspase 1 ◽  
Activation Assay

Abstract INTRODUCTION Glioblastoma multiforme (GBM) is the most aggressive form of primary brain cancer. A subpopulation of multipotent cells termed GBM cancer stem cells (CSCs) play a critical role in tumor initiation and maintenance, drug resistance, and recurrence following surgery. New therapeutic strategies for the treatment of GBM have recently focused on targeting CSCs. Here we have used an unbiased large-scale screening approach to identify drug-like small molecules that induce apoptosis in GBM CSCs in a cell type-selective manner. METHODS A luciferase-based survival assay of patient-derived GBM CSC lines was established to perform a large-scale screen of ∼one million drug-like small molecules with the goal of identifying novel compounds that are selectively toxic to chemoresistant GBM CSCs. Compounds found to kill GBM CSC lines as compared to control cell types were further characterized. A caspase activation assay was used to evaluate the mechanism of induced cell death. A xenograft animal model using patient-derived GBM CSCs was employed to test the leading candidate for suppression of in vivo tumor formation. RESULTS We identified a small molecule, termed RIPGBM, from the cell-based chemical screen that induces apoptosis in primary patient-derived GBM CSC cultures. The cell type-dependent selectivity of RIPGBM appears to arise at least in part from redox-dependent formation of a proapoptotic derivative, termed cRIPGBM, in GBM CSCs. cRIPGBM induces caspase 1-dependent apoptosis by binding to receptor-interacting protein kinase 2 (RIPK2) and acting as a molecular switch, which reduces the formation of a prosurvival RIPK2/TAK1 complex and increases the formation of a proapoptotic RIPK2/caspase 1 complex. In an intracranial GBM xenograft mouse model, RIPGBM was found to significantly suppress tumor formation. CONCLUSIONS Our chemical genetics-based approach has identified a small molecule drug candidate and a potential drug target that selectively targets cancer stem cells and provides an approach for the treatment of GBMs.

Magnetic separation as a new method for the extraction of small molecules from biological fluids of humans

2011 ◽  
Vol 66 (9) ◽  
pp. 807-814 ◽  
Author(s):  
I. I. Sukhanova ◽  
M. A. Dikunets ◽  
E. D. Viryus ◽  
G. M. Rodchenkov
Keyword(s):  
Small Molecules ◽  
Magnetic Separation ◽  
Biological Fluids ◽  
New Method

scholarly journals Numerical study of flow patterns and heat transfer in mini twisted oval tubes

2015 ◽  
Vol 26 (12) ◽  
pp. 1550140 ◽  
Author(s):  
Amin Ebrahimi ◽  
Ehsan Roohi
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Performance ◽  
Numerical Study ◽  
Critical Role ◽  
Reynolds Numbers ◽  
Flow Patterns ◽  
Working Fluid ◽  
Transfer Performance ◽  
Temperature Dependent ◽  
Overall Performance

Flow patterns and heat transfer inside mini twisted oval tubes (TOTs) heated by constant-temperature walls are numerically investigated. Different configurations of tubes are simulated using water as the working fluid with temperature-dependent thermo-physical properties at Reynolds numbers ranging between 500 and 1100. After validating the numerical method with the published correlations and available experimental results, the performance of TOTs is compared to a smooth circular tube. The overall performance of TOTs is evaluated by investigating the thermal-hydraulic performance and the results are analyzed in terms of the field synergy principle and entropy generation. Enhanced heat transfer performance for TOTs is observed at the expense of a higher pressure drop. Additionally, the secondary flow generated by the tube-wall twist is concluded to play a critical role in the augmentation of convective heat transfer, and consequently, better heat transfer performance. It is also observed that the improvement of synergy between velocity and temperature gradient and lower irreversibility cause heat transfer enhancement for TOTs.

scholarly journals Spectrofluorometric determination of nicardipine, nifedipine and isradipine in pharmaceutical preparations and biological fluids

2008 ◽  
Vol 6 (2) ◽  
pp. 222-228 ◽  
Author(s):  
Sheikha Al-Ghannam ◽  
Abeer Al-Olyan
Keyword(s):  
Fluorescence Intensity ◽  
Reaction Pathway ◽  
Biological Fluids ◽  
Sodium Dodecyl ◽  
Pharmaceutical Preparations ◽  
Reduction Reaction ◽  
Factors Affecting ◽  
Plasma And Urine Samples

AbstractA simple and highly sensitive spectrofluorometric method was developed for the determination of some 1,4-dihydropyridine compounds namely, nicardipine, nifedipine and isradipine in pharmaceutical preparations and biological fluids. The method is based on the reduction of nicardipine, nifedipine and isradipine with Zn/HCl and measuring the fluorescence intensity obtained (λem/λex) at 460/364, 450/393 and 446/360 nm, respectively. The factors affecting the development of the fluorophore and its stability were studied and optimized. The effect of some surfactants such as β-cyclodextrin (βCD), carboxymethylcelullose (CMC), sodium dodecyl sulphate (SDS) and triton X-100, on the fluorescence intensity was studied. The fluorescence intensity-concentration plots of nicardipine, nifedipine and isradipine were rectilinear over the ranges 0.4–6.0, 0.2–4.0 and 0.1–9.0 μg ml−1 with detection limits of 0.0028, 0.017 and 0.016 μg ml−1, respectively. The proposed method was successfully applied to commercial tablets containing the compounds; the percentage recovery agreed well with those obtained using the official methods. The method was further extended to the in vitro determination of the compounds in spiked human plasma and urine samples. A proposal of the reduction reaction pathway was postulated.

An Empirical Analysis of FII Movement and Currency Value in India

2015 ◽  
pp. 207-217
Author(s):  
Saurabh Sen ◽  
Ruchi L. Sen
Keyword(s):  
Exchange Rate ◽  
Exchange Rates ◽  
Critical Role ◽  
Institutional Investment ◽  
Currency Futures ◽  
Overall Performance ◽  
Foreign Institutional Investors ◽  
Us Dollar ◽  
The Impact ◽  
The Relationship

India opened its stock market to foreign investors in September 1992 and has received portfolio investment from foreigners in the form of foreign institutional investment in equities and other markets including derivatives. It has emerged as one of the most influential groups to play a critical role in the overall performance of the Indian economy. The liberalization of FII flows into the Indian capital market since 1993 has had a significant impact on the economy. With increased volatility in exchange rate and to mitigate the risk arising out of excess volatility, currency futures were introduced in India in 2008, which is considered a second important structural change. This chapter examines the impact of the Foreign Institutional Investors (FIIs) on the exchange rate and analyzes the relationship between FII and Indian Rupee-US Dollar exchange rates.

scholarly journals Sensitive Analysis of Idarubicin in Human Urine and Plasma by Liquid Chromatography with Fluorescence Detection: An Application in Drug Monitoring

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5799
Author(s):  
Olga Maliszewska ◽  
Natalia Treder ◽  
IIona Olędzka ◽  
Piotr Kowalski ◽  
Natalia Miękus ◽  
...  
Keyword(s):  
Liquid Chromatography ◽  
Human Plasma ◽  
Fluorescence Detection ◽  
Limit Of Detection ◽  
Solid Phase ◽  
Biological Fluids ◽  
Internal Standard ◽  
Urine Samples ◽  
Human Plasma And Urine ◽  
Plasma And Urine Samples

A new approach for the sensitive, robust and rapid determination of idarubicin (IDA) in human plasma and urine samples based on liquid chromatography with fluorescence detection (LC-FL) was developed. Satisfactory chromatographic separation of the analyte after solid-phase extraction (SPE) was performed on a Discovery HS C18 analytical column using a mixture of acetonitrile and 0.1% formic acid in water as the mobile phase in isocratic mode. IDA and daunorubicin hydrochloride used as an internal standard (I.S.) were monitored at the excitation and emission wavelengths of 487 and 547 nm, respectively. The method was validated according to the FDA and ICH guidelines. The linearity was confirmed in the range of 0.1–50 ng/mL and 0.25–200 ng/mL, while the limit of detection (LOD) was 0.05 and 0.125 ng/mL in plasma and urine samples, respectively. The developed LC-FL method was successfully applied for drug determinations in human plasma and urine after oral administration of IDA at a dose of 10 mg to a patient with highly advanced alveolar rhabdomyosarcoma (RMA). Moreover, the potential exposure to IDA present in both fluids for healthcare workers and the caregivers of patients has been evaluated. The present LC-FL method can be a useful tool in pharmacokinetic and clinical investigations, in the monitoring of chemotherapy containing IDA, as well as for sensitive and reliable IDA quantitation in biological fluids.

Computational design, synthesis and utilization of a magnetic molecularly imprinted polymer on graphene oxide nanosheets for highly selective extraction and determination of buprenorphine in biological fluids and tablets

2018 ◽  
Vol 10 (43) ◽  
pp. 5214-5226 ◽  
Author(s):  
Farideh Ganjavi ◽  
Mehdi Ansari ◽  
Maryam Kazemipour ◽  
Leila Zeidabadinejad
Keyword(s):  
Biological Fluids ◽  
Computational Design ◽  
Selective Extraction ◽  
Graphene Oxide Nanosheets ◽  
Imprinted Polymer ◽  
Design Synthesis ◽  
Molecularly Imprinted ◽  
Plasma And Urine Samples ◽  
Computational Design Synthesis

A magnetic MIP for the selective extraction of buprenorphine (BUP) from real plasma and urine samples and tablets based on computational design as a novel procedure has been developed.

scholarly journals Optimization of Industrial Centrifugal Compressors: Part 6A — Studies in Component Performance — Eight Design Cases From 1972 to 1982

1986 ◽  
Author(s):  
David Japikse ◽  
Colin Osborne
Keyword(s):  
Product Development ◽  
Design Optimization ◽  
Rough Surfaces ◽  
Critical Role ◽  
Centrifugal Compressors ◽  
Test Procedures ◽  
Overall Performance ◽  
Leading Edges

The design optimization procedures, used over a period of ten years for a series of compressor designs, are reviewed. Overall performance and test procedures are detailed in Part 6A. The results of detailed interstage measurements are presented and discussed in Part 6B. The critical role of the laboratory in successful product development is illustrated (6B). Manufacturing procedures (castings vs. machining, thick leading edges, rough surfaces, etc.) are shown to significantly influence performance.

Sign in / Sign up

Export Citation Format

Share Document