A novel non-enzymatic glucose sensor based on melamine supported CuO nanoflakes modified electrode

In the present work, we describe a simple electrochemical synthesis of CuO nanoflakes (CuO-NFs) using Cu-melamine complex. The as-prepared CuO nanoflakes was characterized by different physicochemical methods such as high-resolution scanning electron microscopy, elemental analysis and elemental mapping. The effect of different potential cycling towards the morphology of CuO-NFs was studied and discussed. Furthermore, CuO-NFs modified electrode was used as an electrocatalyst for oxidation of glucose in 0.1 M NaOH, and the observed electrochemical oxidation current of glucose was higher than CuNPs modified electrode. Amperometric i-t method was used for the determination of glucose using CuO-NFs modified electrode. Under optimal conditions, the amperometric i-t response of the sensor was linear over the glucose concentrations ranging from 1.0 µM to 1.445 mM with the detection limit of 0.35 µM. In addition, the selectivity of the sensor was tested in the presence of different potentially interfering compounds. The practicality of the sensor was also evaluated in human serum samples and shows acceptable recovery of glucos

Voltammetric determination of catechol based on a glassy carbon electrode modified with a composite consisting of graphene oxide and polymelamine

The authors describe an voltammetric catechol (CC) assay based on the use of a glassy carbon electrode (GCE) modified with a composite consisting of graphene oxide and polymelamine (GO/PM). The modified GCE was characterized by field emission scanning electron microscopy, elemental analysis, Raman spectroscopy and FTIR. Cyclic voltammetry reveals a well-defined response to CC, with an oxidation peak current that is distinctly enhanced compared to electrodes modified with GO or PM only. The combined synergetic activity of GO and PM in the composite also results in a lower oxidation potential. Differential pulse voltammetry (DPV) shows a response that is linear in the 0.03 to 138 μM CC concentration range. The detection limit is 8 nM, and the sensitivity is 0.537 μA⋅μM−1 ⋅cm−2 . The sensor is selective for CC even in the presence of potentially interfering compounds including hydroquinone, resorcinol and dopamine. The modified GCE is highly reproducible, stable, sensitive, and shows an excellent practicability for detection of CC in water samples

Author's personal copy A novel hybrid feature selection via Symmetrical Uncertainty ranking based local memetic search algorithm

a b s t r a c t A novel correlation based memetic framework (MA-C) which is a combination of genetic algorithm (GA) and local search (LS) using correlation based filter ranking is proposed in this paper. The local filter method used here fine-tunes the population of GA solutions by adding or deleting features based on Symmetrical Uncertainty (SU) measure. The focus here is on filter methods that are able to assess the goodness or ranking of the individual features. Empirical study of MA-C on several commonly used datasets from the large-scale Gene expression datasets indicates that it outperforms recent existing methods in the literature in terms of classification accuracy, selected feature size and efficiency. Further, we also investigate the balance between local and genetic search to maximize the search quality and efficiency of MA-C

An Improved Correlation-Based Algorithm with Discretization for Attribute Reduction in Data Clustering

Attribute reduction aims to reduce the dimensionality of large scale data without losing useful information and is an important topic of knowledge discovery, data clustering, and classification. In this paper, we aim to solve the current problem that a continuous attribute in a clustering or classification algorithm must be made discrete. We propose a new algorithm of data reduction based on a correlation model with data discretization. It deals with selection of continuous attributes from a very large set of attributes. The proposed algorithm is an extended version of the Fast Correlation-based filter algorithm and is named FCBF+. The FCBF+ algorithm performs the discretization of continuous attributes in an efficient manner. Then it selects the relevant attributes from a very large set of attributes. Performance evaluation is done on clustering accuracy for all the features, and a reduced set of features is obtained using FCBF+. It is found that the proposed FCBF+ algorithm improves the clustering accuracy of various clustering algorithms

Distinct gene expression profiles underlie morphological and etiological differences in pediatric cataracts

Purpose: Pediatric cataract is a major cause of preventable childhood blindness worldwide. Although genetic mutations or infections have been described in patients, the mechanistic basis of human cataract development remains poorly understood. Therefore, gene expression of structural, developmental, profibrotic, and transcription factors in phenotypically and etiologically distinct forms of pediatric cataracts were evaluated. Methods: This cross-sectional study included 89 pediatric cataract subjects subtyped into 1) prenatal infectious (cytomegalovirus, rubella, and combined cytomegalovirus with rubella infection), 2) prenatal non-infectious, 3) posterior capsular anomalies, 4) postnatal, 5) traumatic, and 6) secondary, and compared to clear, non-cataractous material of eyes with the subluxated lenses. Expression of lens structure-related genes (Aqp-0, HspA4/Hsp70, CrygC), transcription factors (Tdrd7, FoxE3, Maf, Pitx 3) and profibrotic genes (Tgfβ, Bmp7, αSmA, vimentin) in surgically extracted cataract lens material were studied and correlated clinically. Results: In cataract material, the lens-related gene expression profiles were uniquely associated with phenotype/etiology of different cataracts. Postnatal cataracts showed a significantly altered FoxE3 expression. Low levels of Tdrd7 expression correlated with posterior subcapsular opacity, whereas CrygC correlated significantly with anterior capsular ruptures. The expression of Aqp0 and Maf was elevated in infectious cataracts, particularly in CMV infections, compared to other cataract subtypes. Tgfβ showed significantly low expression in various cataract subtypes, whereas vimentin had elevated gene expression in infectious and prenatal cataracts. Conclusion: A significant association between lens gene expression patterns in phenotypically and etiologically distinct subtypes of pediatric cataracts suggests regulatory mechanisms in cataractogenesis. The data reveal that cataract formation and presentation is a consequence of altered expression of a complex network of genes

Integrated Analysis of Cancer Tissue and Vitreous Humor from Retinoblastoma Eyes Reveals Unique Tumor-Specific Metabolic and Cellular Pathways in Advanced and Non-Advanced Tumors

Retinoblastoma (Rb) is a pediatric intraocular malignancy that is proposed to originate from maturing cone cell precursors in the developing retina. The molecular mechanisms underlying the biological and clinical behaviors are important to understand in order to improve the management of advanced-stage tumors. While the genetic causes of Rb are known, an integrated understanding of the gene expression and metabolic processes in tumors of human eyes is deficient. By integrating transcriptomic profiling from tumor tissues and metabolomics from tumorous eye vitreous humor samples (with healthy, age-matched pediatric retinae and vitreous samples as controls), we uncover unique functional associations between genes and metabolites. We found distinct gene expression patterns between clinically advanced and non-advanced Rb. Global metabolomic analysis of the vitreous humor of the same Rb eyes revealed distinctly altered metabolites, indicating how tumor metabolism has diverged from healthy pediatric retina. Several key enzymes that are related to cellular energy production, such as hexokinase 1, were found to be reduced in a manner corresponding to altered metabolites; notably, a reduction in pyruvate levels. Similarly, E2F2 was the most significantly elevated E2F family member in our cohort that is part of the cell cycle regulatory circuit. Ectopic expression of the wild-type RB1 gene in the Rb-null Y79 and WERI-Rb1 cells rescued hexokinase 1 expression, while E2F2 levels were repressed. In an additional set of Rb tumor samples and pediatric healthy controls, we further validated differences in the expression of HK1 and E2F2. Through an integrated omics analysis of the transcriptomics and metabolomics of Rb, we uncovered a significantly altered tumor-specific metabolic circuit that reduces its dependence on glycolytic pathways and is governed by Rb1 and HK1