Label-Free Protein Glycosylation Analysis Using NanoMonitor-An Ultrasensitive Electrochemical Biosensor.

Glycans (oligosaccharide chains attached to glycoproteins) are a promising class of biomarkers, found in body fluids such as serum, saliva, urine, etc., that can be used for the diagnosis of disease conditions. Subtle changes in glycans resulting from altered glycosylation machinery have been reported during various diseases, including carcinogenesis.

Development and In Vitro Evaluation of Vitamin E-Enriched Nanoemulsion Vehicles Loaded with Genistein for Chemoprevention Against UVB-Induced Skin Damage.

There is a great need for effective protection against cutaneous pathologies arising from chronic exposure to harmful solar UVB radiations. A promising pharmaceutical strategy to improve the efficacy of chemotherapeutic/preventative natural compounds (e.g.

Nanochannel-based electrochemical sensor for the detection of pharmaceutical contaminants in water.

Effective real-time monitoring is the key to understanding and tackling the issue of pharmaceutical contamination of water. This research demonstrates the utility of an alumina nanochannel-based electrochemical sensor platform for the detection of ibuprofen in water derived from various sources. Our results indicate that the sensor is highly sensitive with a limit of detection at 0.

Factors affecting severity of tinnitus - a follow-up study of tinnitus subjects at an Ear Nose Throat clinic in Sweden.

Objective: The aim of the present study was to examine whether perceived tinnitus severity changes over time, and if so what factors contribute to this change.

Design: A modified Swedish version of tinnitus severity questionnaire (MS-TSQ) was used to examine changes in tinnitus severity over a period of time.

Study Sample: The MS-TSQ questionnaire was completed by 455 subjects visiting an Ear, Nose and Throat (ENT) clinic in Sweden as part of baseline assessment (Sb).

Label-free measuring and mapping of binding kinetics of membrane proteins in single living cells.

Membrane proteins mediate a variety of cellular responses to extracellular signals. Although membrane proteins are studied intensively for their values as disease biomarkers and therapeutic targets, in situ investigation of the binding kinetics of membrane proteins with their ligands has been a challenge. Traditional approaches isolate membrane proteins and then study them ex situ, which does not reflect accurately their native structures and functions.

NanoProbeArrays for the analysis of ultra-low-volume protein samples using piezoelectric liquid dispensing technology.

Antibody microarrays are gaining popularity as a high-throughput technology to investigate the proteome. However, protein extracts from most body fluid or biopsy samples are available in very small volumes and are often unsuitable for large-scale antibody microarray studies. To demonstrate the potential for protein analysis with as little as a few nanoliters of sample, we have developed a new technology called NanoProbeArrays based on piezoelectric liquid dispensing for non-contact printing and probing of antibody arrays.

Single cells and intracellular processes studied by a plasmonic-based electrochemical impedance microscopy.

Electrochemical impedance spectroscopy is a crucial tool for the detection and study of various biological substances, from DNA and proteins to viruses and bacteria. It does not require any labelling species, and methods based on it have been developed to study cellular processes (such as cell spreading, adhesion, invasion, toxicology and mobility). However, data have so far lacked spatial information, which is essential for investigating heterogeneous processes and imaging high-throughput microarrays.

Efficacy of TRAIL treatment against HPV16 infected cervical cancer cells undergoing senescence following siRNA knockdown of E6/E7 genes.

In this study we investigated E6 and E7 oncogenes from the Human Papilloma Virus as targets for siRNA knockdown in order to boost the efficacy of the anti-cancer drug 'tumor necrosis factor-related apoptosis inducing ligand' (TRAIL). SiHa cells were treated with TRAIL following transfection with E6/E7 siRNA and the expression of death receptors DR4 and DR5, cell viability, apoptosis, senescence and cell cycle analysis were undertaken using flow cytometry, MTT viability assay and cellular β-galactosidase activity assays. E6/E7 siRNA resulted in significant upregulation of death receptors DR4 and DR5 but did not result in an enhanced sensitivity to TRAIL.

NanoMonitor: a miniature electronic biosensor for glycan biomarker detection.

Aim: The goal of our research is to develop an ultrasensitive diagnostic platform called 'NanoMonitor' to enable rapid label-free analysis of a highly promising class of biomarkers called glycans (oligosaccharide chains attached to proteins) with high sensitivity and selectivity. The glycosylation of fetuin - a serum protein - and extracts from a human pancreatic cancer line was analyzed to demonstrate the capabilities of the NanoMonitor.

Material & Methods: The NanoMonitor device consists of a silicon chip with an array of gold electrodes forming multiple sensor sites and works on the principle of electrochemical impedance spectroscopy.

Are small GTPases signal hubs in sugar-mediated induction of fructan biosynthesis?

External sugar initiates biosynthesis of the reserve carbohydrate fructan, but the molecular processes mediating this response remain obscure. Previously it was shown that a phosphatase and a general kinase inhibitor hamper fructan accumulation. We use various phosphorylation inhibitors both in barley and in Arabidopsis and show that the expression of fructan biosynthetic genes is dependent on PP2A and different kinases such as Tyr-kinases and PI3-kinases.

Piezoelectric printing and probing of Lectin NanoProbeArrays for glycosylation analysis.

Glycans have great potential as disease biomarkers and therapeutic targets. However, the major challenge for glycan biomarker identification from clinical samples is the low abundance of key glycosylated proteins. To demonstrate the potential for glycan analysis with nanoliter amounts of glycoprotein, we have developed a new technology (Lectin NanoProbeArray) based on piezoelectric liquid dispensing for non-contact printing and probing of a lectin array.

O-glycosylation of protein subpopulations in alcohol-extracted rice proteins.

Mucin-type O-glycosylation has been well characterized in mammalian systems but not in plants. In this study, the purified alcohol-soluble, non-reduced protein (prolamin) fraction from rice seed was investigated for the occurrence of O-linked oligosaccharides. As storage prolamins are unlikely to be O-glycosylated, any O-glycosylation found was likely to belong to co-extracted proteins, whether because of association with the protein body or solubility.

Sucrose regulated expression of a Ca2+-dependent protein kinase (TaCDPK1) gene in excised leaves of wheat.

Sucrose (Suc) can influence the expression of a large number of genes and thereby regulates many metabolic and developmental processes. However, the Suc sensing and the components of the ensuing signaling transduction pathway leading to the regulation of gene expression are not fully understood. We have shown that protein kinases and phosphatases are involved in the Suc induced expression of fructosyltransferase (FT) genes and fructan accumulation by an hexokinase independent pathway in wheat (Triticum aestivum).

Calcium is essential for fructan synthesis induction mediated by sucrose in wheat.

The role of Ca(2+) in the induction of enzymes involved in fructan synthesis (FSS) mediated by sucrose was studied in wheat (Triticum aestivum). Increase of FSS enzyme activity and induction of the expression of their coding genes by sucrose were inhibited in leaf blades treated with chelating agents (EDTA, EGTA and BAPTA). Ca(2+) channel blockers (lanthanum chloride and ruthenium red) also inhibited the FSS response to sucrose, suggesting the participation of Ca(2+) from both extra- and intra- cellular stores.

Purification, cloning and functional characterization of a fructan 6-exohydrolase from wheat (Triticum aestivum L.).

Fructans, beta2-1 and/or beta2-6 linked polymers of fructose, are produced by fructosyltransferases (FTs) from sucrose. They are important storage carbohydrates in many plants. Fructan reserves, widely distributed in plants, are believed to be mobilized via fructan exohydrolases (FEHs).

Knowledge-based framework for hypothesis formation in biochemical networks.

Motivation: The current knowledge about biochemical networks is largely incomplete. Thus biologists constantly need to revise or extend existing knowledge. The revision and/or extension are first formulated as theoretical hypotheses, then verified experimentally.

Ectopic expression of the mycorrhiza-specific chitinase gene Mtchit 3-3 in Medicago truncatula root-organ cultures stimulates spore germination of glomalean fungi.

Expression of Mtchit 3-3, a class III chitinase gene, is specifically induced by arbuscular mycorrhizal (AM) fungi in roots of the model legume Medicago truncatula and its transcripts accumulate in cells containing arbuscules. Agrobacterium rhizogenes-transformed roots and root-organ cultures of M. truncatula were used to study effects of Mtchit 3-3 on AM fungi.

Distinct regulation of sucrose: sucrose-1-fructosyltransferase (1-SST) and sucrose: fructan-6-fructosyltransferase (6-SFT), the key enzymes of fructan synthesis in barley leaves: 1-SST as the pacemaker.

•  Previously we have cloned sucrose: fructan-6-fructosyltransferase (6-SFT) from barley (Hordeum vulgare) and proposed that synthesis of fructans in grasses depends on the concerted action of two main enzymes: sucrose: sucrose-1-fructosyltransferase (1-SST), as in other fructan producing plants, and 6-SFT, found only in grasses. •  Here we report the cloning of barley 1-SST, verifying the activity of the encoded protein by expression in Pichia pastoris. As expected, the barley 1-SST is homologous to invertases and fructosyltransferases, and in particular to barley 6-SFT.