Nanostructured copper particles-incorporated Nafion-modified electrode for oxygen reduction

The electrocatalytic activity of nanostructured copper particles (represented as Cunano) incorporated Nafion (Nf) film-coated glassy carbon (GC) electrode (GC/Nf/Cunano) towards oxygen reduction was investigated in oxygenated 0.1 M phosphate buffer (pH 7.2). The electrodeposited Cunano in Nf film was characterized by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). The electrocatalytic activity of Cunano at the modified electrode towards oxygen reduction was studied using cyclic voltammetry technique. The molecular oxygen reduction at the GC/Nf/Cunano-modified electrode started at a more positive potential than at a bare GC electrode. A possible reaction mechanism was proposed in which oxygen reduction may proceed through two-step two-electron processes at the GC/Nf/Cunano electrode. The GC/Nf/Cunano electrode shows higher stability for oxy gen reduction in neutral solution and the electrode may find applications in fuel cells

A Study on Nosocomial Infection in Intensive Medical Care Unit-incidence, pattern and etiology

BAKGROUND : Nosocomial infection is defined as an infection which develops 48 hours after admission to hospital and which was not incubating at the time of admission. The nosocomial infection results in increase in hospital stay time, increased morbidity and mortality. The aim of this study was to find the incidence, Etiology of nosocomial infection in intensive medical care unit in Tirunelveli Medical College Hospital. It was conducted in 200 patients from September 2012 to August 2013. METHODS : All patients admitted in IMCU in Tirunelveli Medical college Hospital and stayed in the IMCU for more than 48 hours were included in the study. Data was included in a proforma and analysed using Epidemiological Information Package 2010 developed by Centre for disease control, Atlanta. RESULTS : During the study period out of 200 patients 16 patients developed Nosocomial infection. So the incidence of Nosocomial infection was 8%. The most common Nosocomial infection was urinary tract infection (5.5%) followed by respiratory infection in 2% and blood stream infection in 0.5%.The most common organism causing Nosocomial infection was Klebsiella (5%), E.Coli (2%) and pseudomonas (1%). CONCLUSION : Patients admitted in IMCU are at more risk for developing nosocomial infection than in general wards. In our study Urinary tract infection was the commonest followed by respiratory and blood stream infection. Gram negative organisms were the most common cause in this study

Electrochemical and in situ spectroelectrochemical studies of gold nanoparticles immobilized Nafion matrix modified electrode

Electrochemical and in situ spectroelectrochemical behaviours of phenosafranine (PS+) were studied at the gold nanoparticles (AuNps) immobilized Nafion (Nf) film coated glassy carbon (GC) and indium tin oxide (ITO) electrodes. Cyclic voltammetric studies showed that the PS+ molecules strongly interact with the AuNps immobilized in the Nf matrix through the electrostatic interaction. The presence of AuNps in the Nf film improved the electrochemical characteristics of the incorporated dye molecules. The emission spectra of Nf-AuNps-PS+ films showed that the incorporated PS+ was quenched by AuNps and it could be explained based on the electronic interaction between the AuNps and PS+ molecules. The in situ spectroelectrochemical study showed an improved electrochemical characteristic of the incorporated PS+ molecules at the ITO/Nf-AuNps electrode when compared to the ITO/Nf electrode

Proton coupled electron transfer reaction of phenols with excited state ruthenium(II) - polypyridyl complexes

The reaction of phenols with the excited state, *[Ru(bpy)3]2+ (E0 = 0.76V) and *[Ru(H2dcbpy)3]2+, (dcbpy = 4,4'-dicarboxy-2,2'-bipyridine) (E0 = 1.55 V vs. SCE) complexes in CH3CN has been studied by luminescence quenching technique and the quenching is dynamic. The formation of phenoxyl radical as a transient is confirmed by its characteristic absorption at 400 nm. The kq value is highly sensitive to the change of pH of the medium and ΔG0 of the reaction. Based on the treatment of kq data in terms of energetics of the reaction and pH of the medium, proton coupled electron transfer (PCET) mechanism has been proposed for the reaction

A novel and disposable amperometric hydrazine sensor based on polydimethyldiallylamine stabilized copper(II)hexacyanoferrate nanocubes modified screen-printed carbon electrode

© 2017 The Authors. A cubic shaped copper(II)hexacyanoferrate was prepared by wet chemical method by mixing an equimolar concentration of CuCl 2 with K 3 [Fe(CN) 6 ] 2 in the presence of poly(diallyldimethylammonium chloride) (PDDA). The X-ray diffraction, field emission scanning electron microscopy, elementa l analysis, Fourier transform infrared spectroscopy and thermal gravimetric analysis were used to confirm the formation of PDDA stabilized copper(II)hexacyanoferrate nanocubes (PDDA@copper(II)hexacyanoferrate nanocubes). The electrocatalytic behavior of the PDDA@copper(II)hexacyanoferrate nanocubes modified screenprinted carbon electrode (SPCE) towards electrochemical oxidation of hydrazine was studied by cyclic voltammetry (CV). The CV results revealed that PDDA@copper(II)hexacyanoferrate nanocubes modified SPCE exhibits an enhanced electrocatalytic activity and lower oxidation potential towards hydrazine than bare SPCE. Under optimized conditions, amperometric i-t method was used for the determination hydrazine, and PDDA@copper(II)hexacyanoferrate nanocubes modified SPCE can able to detect hydrazine in the linear concentration ranges from 0.03 to 533.6 μM with a detection limit of 10 nM. The PDDA@copper(II)hexacyanoferrate nanocubes modified SPCE is highly selective in the presence of potentially active interfering compounds including high concentration of ascorbic acid. In addition, the developed hydrazine sensor shows acceptable practicality with excellent long-term stability towards the detection of hydrazine

A robust nitrobenzene electrochemical sensor based on chitin hydrogel entrapped graphite composite

© 2017 An amperometric nitrobenzene (NB) sensor has been developed based on a glassy carbon electrode (GCE) modified with the composite of chitin hydrogel stabilized graphite (GR-CHI) composite. The physicochemical characterization confirmed the formation of GR-CHI composite and was formed by the strong interaction between GR and CHI. Furthermore, GR-CHI composite modified GCE was used to study the electrochemical reduction behavior of NB by cyclic voltammetry (CV) and compared with GR and CHI modified GCEs. The CV results confirmed that GR-CHI composite modified electrode has high catalytic ability and lower reduction potential toward NB than other modified electrodes due to the combined unique properties of exfoliated GR and CHI. The GR-CHI composite modified electrode can be able to detect the NB in the linear response range from 0.1 to 594.6 µM with the lower detection limit of 37 nM by amperometric i–t method. The selectivity of the sensor is evaluated in the presence of nitroaromatic, biologically active and dihydroxybenzene compounds. The sensor shows appropriate practicality and good repeatability toward detection of NB in lab water samples

Histone citrullination represses miRNA expression resulting in increased oncogene mRNAs in somatolactotrope cells.

Peptidylarginine deiminase (PAD) enzymes convert histone arginine residues into citrulline to modulate chromatin organization and gene expression. Although PADs are expressed in anterior pituitary gland cells, their functional role and expression in pituitary adenomas is unknown. To begin to address these questions, we first examined normal human pituitaries and pituitary adenomas and found that PAD2, PAD4 and citrullinated histones are highest in prolactinomas and somatoprolactinomas. In the somatoprolactinoma-derived GH3 cell line, PADs citrullinate histone H3, which is attenuated by a pan-PAD inhibitor. RNA-sequencing and ChIP studies show that the expression of microRNAs let-7c-2, miR-23b and miR-29c is suppressed by histone citrullination. Our studies demonstrate that these miRNAs directly target the mRNA of the oncogenes HMGA, IGF-1 and N-MYC, which are highly implicated in human prolactinoma/somatoprolactinoma pathogenesis. Our results are the first to define a direct role for PAD catalyzed histone citrullination in miRNA expression, which may underlie the etiology of prolactinoma and somatoprolactinoma tumors through regulation of oncogene expression

Effectiveness of pharmacogenomic tests including CYP2D6 and CYP2C19 genomic variants for guiding the treatment of depressive disorders: Systematic review and meta-analysis of randomized controlled trials

Major depressive disorders are prevalent conditions with limited treatment response and remission. Pharmacogenomics tests including CYP2D6 and CYP2C19 genomic variants provide the most reliable actionable approach to guide choice and dosing of antidepressants in major depression to improve outcome. We carried out a meta-analysis and meta-regression analyses of randomised controlled trials evaluating pharmacogenomic tests with CYP2D6 and CYP2C19 polymorphisms in major depression. A systematic review was conducted according to PRISMA and Cochrane guidelines to search several electronic databases. Logarithmically transformed odds ratios (OR) and confidence intervals (CI) for improvement, response and remission were calculated. A random-effects meta-analysis and meta-regression analyses were subsequently carried out. Twelve randomised controlled trials were included. Pharmacogenomic tests in the treatment of depression were more effective than treatment as usual for improvement (OR:1.63, CI: 1.19-2.24), response (OR: 1.46; CI: 1.16-1.85) and remission (OR: 1.85; CI: 1.23-2.76) with no evidence of publication bias. Remission was less favourable in recent studies. The results are promising but cautious use of pharmacogenomics in major depression is advisable. PROSPERO registration ID: CRD42021261143

Flower-like strontium molybdate anchored on 3D N-rich reduced graphene oxide aerogel composite: An efficient catalyst for the detection of lethal pollutant nitrobenzene in water samples

Nitrobenzene (NB) is a carcinogenic water pollutant that can have dangerous effects on humans, animals, and the environment even in trace amounts. It can persist in contaminated sites and leach into the adjacent aquatic environment. Therefore, the detection of trace amounts of NB is of great interest. To address this challenge, we have fabricated strontium molybdate microflowers (SrMoO4, SMO MFs) grown on nitrogen-rich, porous three-dimensional (3D) reduced graphene oxide aerogels (SMO/N-rGO) for sensitive detection of NB in water samples. The 3D N-rGO and SMO/N-rGO composites were prepared by simple hydrothermal and precipitation methods. The fabricated SMO/N-rGO composites exhibited a porous and 3D structure with a strong synergistic effect between the SMO MFs and the N-rich porous rGO sheets with open voids that facilitate the diffusion of NB. The electrochemical detection of NB at the SMO/N-rGO modified electrode was significantly enhanced. Using amperometry (i-t), the modified SMO/N-rGO sensor was shown to have two linear response ranges in the sensing of NB, with the lower linear concentration range from 7.1 nM to 1.0 mM and the higher linear concentration range varying from 1.1 mM to 2.5 mM. In addition, the limit of detection (LOD) was calculated to be 2.1 nM using the amperometric (i-t) technique. Common nitro derivatives, biomolecules, and cations often found in water systems had no influence on the detection of NB. At the same time, a good recovery of 96.1–99.6% was obtained for real-time monitoring analysis in tap and lake water samples. In this work, new electrochemical sensors for monitoring various pollutants are developed based on anchoring conductive metal oxide electrocatalysts on porous 3D carbon aerogels

Hybrid assembly with long and short reads improves discovery of gene family expansions

BACKGROUND: Long-read and short-read sequencing technologies offer competing advantages for eukaryotic genome sequencing projects. Combinations of both may be appropriate for surveys of within-species genomic variation. METHODS: We developed a hybrid assembly pipeline called "Alpaca" that can operate on 20X long-read coverage plus about 50X short-insert and 50X long-insert short-read coverage. To preclude collapse of tandem repeats, Alpaca relies on base-call-corrected long reads for contig formation. RESULTS: Compared to two other assembly protocols, Alpaca demonstrated the most reference agreement and repeat capture on the rice genome. On three accessions of the model legume Medicago truncatula, Alpaca generated the most agreement to a conspecific reference and predicted tandemly repeated genes absent from the other assemblies. CONCLUSION: Our results suggest Alpaca is a useful tool for investigating structural and copy number variation within de novo assemblies of sampled populations