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Biopolymer films have drawn growing demand for their application in the point of care domain owing to their biocompatibility, eco-friendly, and eligibility for in vivo analyses. However, their poor conductivity restricts their sensitivity in diagnostics. For high-quality electrochemical biosensor monitoring, two vital factors to be greatly paid attention are the effective merge of amplification modifiers with transducing surface and the superior linking across the recognition interface. Here, we introduce an enzyme-free electrochemical biosensor based on electrosynthesized biocompatible WO3/poly glutamic acid nano-biocomposites to address the hardships specific to the analysis of circulating proteins clinical samples. In addition to its green synthesis route, the poor tendency of both components of the prepared nano-biocomposite to amine groups makes it excellent working in untreated biological samples with high contents of proteins. Several electrochemical and morphological investigations (SEM, EDX, and dot mapping) were fulfilled to gain a reliable and trustful standpoint of the framework. By using this nanobiosensor, the concentration of HER-2 was detectable as low as 1 fg mL−1 with a wide linear response between 1 ng mL−1 and 1 fg mL−1. Meanwhile, the protocol depicted ideal specificity, stability, and reproducibility for the detection of HER-2 protein in untreated serum samples of breast cancer patients. [ABSTRACT FROM AUTHOR]

Abstract Background Nipple pain and damage in breastfeeding mothers are common causes of premature breastfeeding cessation. Peppermint water is popularly used for the prevention of nipple cracks in the North West of Iran. The aim of this study was to determine the effectiveness of peppermint water in the prevention of nipple cracks during breastfeeding in comparison with the application of expressed breast milk (EBM). Methods One hundred and ninety-six primiparous breastfeeding women who gave birth between February and May 2005 in a teaching hospital in Tabriz, Iran, were randomized to receive either peppermint water or EBM. Each woman was followed for up to three visits or telephone calls within 14 days and then by telephone call at week six postpartum. Results Women who were randomized to receive peppermint water were less likely to experience nipple and areola cracks (9%) compared to women using EBM (27%; p < 0.01). Women who used the peppermint water on a daily basis were less likely to have a cracked nipple than women who did not use peppermint water (relative risk 3.6, 95%CI: 2.9, 4.3). Nipple pain in the peppermint water group was lower than the expressed breast milk group (OR 5.6, 95% CI: 2.2, 14.6; p < 0.005). Conclusion This study suggests that peppermint water is effective in the prevention of nipple pain and damage. Further studies are needed to assess the usefulness of peppermint water in conjunction with correct breastfeeding techniques. Trial registration number: NCT00456404

Introduction: Beta-Boswellic acid (BBA) is a pentacyclic terpene which has been obtained from frankincense and its beneficial effects on neurodegenerative disorders such as Alzheimer's disease (AD) have been addressed. Methods: In the present study, thermodynamic and kinetic aspects of BBA interaction with Tau protein as one of the important proteins involved in AD in the absence and presence of glucose has been investigated using surface plasmon resonance (SPR) method. Tau protein was immobilized onto the carboxy methyl dextran chip and its binding interactions with BBA were studied at physiological pH at various temperatures. Glucose interference with these interactions was also investigated. Results: Results showed that BBA forms a stable complex with Tau (KD=8.45×10-7 M) at 298 K. Molecular modeling analysis showed a hydrophobic interaction between BBA and HVPGGG segment of R2 and R4 repeated domains of Tau. Conclusion: The binding affinity increased by temperature enhancement, while it decreased significantly in the presence of glucose. Both association and dissociation of the BBA-Tau complex were accompanied with an entropic activation barrier; however, positive enthalpy and entropy changes revealed that hydrophobic bonding is the main force involved in the interaction. [ABSTRACT FROM AUTHOR]

A novel series of 2‐(4‐alkoxybenzylidine)‐2,3‐dihydro‐5,6‐dimethoxy‐1H‐inden‐1‐one derivatives were designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBuChE) enzymes. The in vitro studies showed that some of these molecules exhibited a significant ability to inhibit AChE and BuChE. Among them, 2‐[4‐[2‐(piperidine‐1‐yl)ethoxy]benzylidine]‐2,3‐dihydro‐5,6‐dimethoxy‐1H‐inden‐1‐one exhibited the most potent inhibitory activity with IC50 values of 0.3 and 7.4 μM for AChE and BuChE, respectively. This compound was found to be less toxic than donepezil. [ABSTRACT FROM AUTHOR]

Introduction: The detection of micrometer-sized particles like cells is limited by surface plasmon resonance (SPR) biosensors because of having a depth of evanescent wave <500 nm. In this study, for the first time, we exhibited the use of streptavidin-functionalized gold nanorods (GNRs) as intensification labels for detection of cell surface markers in SPR-based biosensors. Methods: The GNRs (ʎ max: 735 nm) were modified with streptavidin using EDC/NHS coupling method and human umbilical vein endothelial cells (HUVECs) were selected as the cell model for detecting VE-cadherin on cell surface using real-time SPR device in the 785 nm wavelength of the laser source. Results: The investigations revealed that the plasmonic field extension produced from the gold layer and GNRs resulted in multiple enhancement of SPR signals when the wavelength of laser source in SPR instrument was matched with the wavelength of maximum absorbance in GNRs. Moreover, the results showed that the growth of ΔRU value in specific and non-specific bindings for various cell number injections were produced with increasing the cell number. Conclusion: The results displayed that cell detection can be performed in real-time form without any need to a time-consuming process used in conventional methods like immunocytochemistry, flow cytometry, and western blotting. [ABSTRACT FROM AUTHOR]

Introduction : Dopamine is one of the key neurotransmitters (NTs) in nature, which plays a crucial role in the mammalian central nervous system (CNS). Its selective determination in the biological fluids is an essential need in the field of biomedicine studies. Methods : In this work, an amperometric sensor was developed using Nafion-coated cadmium pentacyanonitrosylferrate (CdPCNF) modified glassy carbon (GC) electrode (Nafion|CdPCNF|GC electrode) as an electrocatalyst to detect dopamine (DA) in human serum samples. To develop this sensor, the surface of bare GC electrode was coated with the film of CdPCNF through an electropolymerization method and then the modified electrode was coated with Nafion to minimize interferences, especially those arising from the presence of anionic compounds. The electrocatalytic behavior of the modified electrodes was studied using the cyclic voltammetry and amperometry, and then the ability of the sensor for the determination of DA in synthetic and biological samples was investigated. Results : The modified electrode was showed a significant electrocatalytic activity for the oxidation of DA at pH 7.4. The limit of detection (LOD) was 0.7 µM and also no interference effects arose from ascorbic acid (AA), uric acid (UA) or the other biological NTs was observed in the DA detection using the modified Nafion|CdPCNF|GC electrode. Conclusion : In comparison with the bare electrode, the Nafion|CdPCNF|GC electrode could determine DA in the biological samples with adequate sensitivity and selectivity. Therefore, we propose that the modified electrode is utilizable as an amperometric DA sensor for the biological sample analysis. [ABSTRACT FROM AUTHOR]

A great body of evidence unveiled the existence of different stem cell types in various tissues with efficient capability for self-renewal and differentiation. Characterization and enumeration of a specific stem cell population seem difficult because these cells consist of a small percentage of cells within different milieu. As such, due to lack of accuracy provided by convenient methods, biosensing techniques are at the center of attention to improve stem cells characterization with high rate of sensitivity and specificity. In line with this statement, bio-sensing, as a sensitive analytical method, opens novel avenues in biological aspects. Physicochemical signals produced by the interaction of analyte-ligands could be applicable for a wide range of scientific fields such as chemical, biochemical, pharmaceutical and immunological purposes. Noninvasive and label free monitoring methods without need to stain, fix, lyse, or fluorescent-tags are desirable in basic stem cell technology and therapeutic applications of cells. We, here, highlighted basic concepts and terms associated with label free biosensor technology for measuring cell entity, evaluating cell surface marker, and peculiarly in the field of stem cell biology. Furthermore, different aspects and methodologies concerning with bio-sensing techniques, including photonic-based detection systems like Surface Plasmon Resonance (SPR) assays, Impedance-based method , Quartz Crystal Microbalance (QCM) and paper based detection of lateral flow biosensor (LFB) were discussed. [ABSTRACT FROM AUTHOR]