Nanoplasmonic NO Sensor with a Sub-10 Parts per Billion Limit of Detection in Urban Air.

Urban air pollution is a critical health problem in cities all around the world. Therefore, spatially highly resolved real-time monitoring of airborne pollutants, in general, and of nitrogen dioxide, NO, in particular, is of utmost importance. However, highly accurate but fixed and bulky measurement stations or satellites are used for this purpose to date.

Scalable Electronic Ratchet with Over 10% Rectification Efficiency.

Electronic ratchets use a periodic potential with broken inversion symmetry to rectify undirected (electromagnetic, EM) forces and can in principle be a complement to conventional diode-based designs. Unfortunately, ratchet devices reported to date have low or undetermined power conversion efficiencies, hampering applicability. Combining experiments and numerical modeling, field-effect transistor-based ratchets are investigated in which the driving signal is coupled into the accumulation layer via interdigitated finger electrodes that are capacitively coupled to the field effect transistor channel region.

Interaction Forces on Polyampholytic Hydrogel Gradient Surfaces.

Rational design and informed development of nontoxic antifouling coatings requires a thorough understanding of the interactions between surfaces and fouling species. With more complex antifouling materials, such as composites or zwitterionic polymers, there follows also a need for better characterization of the materials as such. To further the understanding of the antifouling properties of charge-balanced polymers, we explore the properties of layered polyelectrolytes and their interactions with charged surfaces.

Swallowing Dysfunction in Adult Patients with Chiari I Malformation.

 Swallowing difficulties have been reported in patients with Chiari I malformation (CMI) with a prevalence of 4 to 47%, but existing evidence is based only on case reports. We aimed to prospectively study swallowing function in adult patients with CMI before and 3 months after surgical decompression.  We included all adult patients diagnosed with CMI from September 2015 to October 2017 who underwent a planned surgery at Sahlgrenska University Hospital, Sweden.

Added Value of pH Multichannel Intraluminal Impedance in Adults Operated for Esophageal Atresia.

Background: Gastroesophageal reflux (GER) and dysphagia are common following repaired esophageal atresia (EA). The risk of esophagitis and Barrett esophagus is increased compared with the general population. As yet, the causes are not fully explained.

pH-control of the protein resistance of thin hydrogel gradient films.

We report on the preparation and characterization of thin polyampholytic hydrogel gradient films permitting pH-controlled protein resistance via the regulation of surface charges. The hydrogel gradients are composed of cationic poly(2-aminoethyl methacrylate hydrochloride) (PAEMA), and anionic poly(2-carboxyethyl acrylate) (PCEA) layers, which are fabricated by self-initiated photografting and photopolymerization (SIPGP). Using a two-step UV exposure procedure, a polymer thickness gradient of one component is formed on top of a uniform layer of the oppositely charged polymer.

Resonance-mode electrochemical impedance measurements of silicon dioxide supported lipid bilayer formation and ion channel mediated charge transport.

A single-chip electrochemical method based on impedance measurements in resonance mode has been employed to study lipid monolayer and bilayer formation on hydrophobic alkanethiolate and SiO(2) substrates, respectively. The processes were monitored by temporally resolving changes in interfacial capacitance and resistance, revealing information about the rate of formation, coverage, and defect density (quality) of the layers at saturation. The resonance-based impedance measurements were shown to reveal significant differences in the layer formation process of bilayers made from (i) positively charged lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-ethylphosphocholine (POEPC), (ii) neutral lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) on SiO(2), and (iii) monolayers made from POEPC on hydrophobic alkanethiolate substrates.

Real-time quantification of microscale bioadhesion events in situ using imaging surface plasmon resonance (iSPR).

From macro- to nanoscales, adhesion phenomena are all-pervasive in nature yet remain poorly understood. In recent years, studies of biological adhesion mechanisms, terrestrial and marine, have provided inspiration for "biomimetic" adhesion strategies and important insights for the development of fouling-resistant materials. Although the focus of most contemporary bioadhesion research is on large organisms such as marine mussels, insects and geckos, adhesion events on the micro/nanoscale are critical to our understanding of important underlying mechanisms.

Novel application of imaging surface plasmon resonance for in situ studies of the surface exploration of marine organisms.

The surface interactions of exploring cyprids of the barnacle Semibalanus balanoides were studied in situ using imaging surface plasmon resonance. It was demonstrated how the deposition of a proteinaceous adhesive could be followed in real time as the cyprids explored and temporarily attached to a surface. Furthermore, the amount of protein left on the surface when the cyprids moved on could be quantified.

DNA chips with conjugated polyelectrolytes in resonance energy transfer mode.

We show how to use well-defined conjugated polyelectrolytes (CPEs) combined with surface energy patterning to fabricate DNA chips utilizing fluorescence signal amplification. Cholesterol-modified DNA strands in complex with a CPE are adsorbed to a surface energy pattern, formed by printing with soft elastomer stamps. Hybridization of the surface bound DNA strands with a short complementary strand from solution is monitored using both fluorescence microscopy and imaging surface plasmon resonance.

Lateral control of protein adsorption on charged polymer gradients.

This work describes the fabrication, characterization, and protein adsorption behavior of charged polymer gradients. The thin gradient films were fabricated by a two-step technique using UV-initiated free-radical polymerization in a reactor with a moving shutter. A homogeneous layer of cationic poly(2-aminoethyl methacrylate hydrochloride) was first formed, followed by a layer of oppositely charged poly(2-carboxyethyl acrylate) with a continuously increasing thickness.

A multiple-ligand approach to extending the dynamic range of analyte quantification in protein microarrays.

This work describes a concept for extending the dynamic range of quantification in an affinity biosensor assay by using a set of ligands with different affinities toward a common analyte. Three synthetic, biotinylated polypeptides capable of binding a model protein analyte with different affinities (10(-9) M < or = K(d) < or = 10(-7) M) were immobilized in a microarray format on a gold slide covered with an oligo(ethylene glycol)-containing alkane thiolate self-assembled monolayer. A five-element affinity array, comprising single-peptide spots as well as spots where peptides were immobilized in mixtures, was realized by means of piezodispensation.

Potential and current density distributions at electrodes intended for bipolar patterning.

This paper deals with the use of reaction gradients on bipolar electrodes for the patterning of electrode surfaces.More specifically, the potential and current density distributions in two setups containing bipolar electrodes were investigated to optimize and design specific gradient geometries. Comparisons with simulations based on simple conductivity models showed a good qualitative agreement, demonstrating that these models could be used to predict bipolar behavior in more complex setups.

Gradient hydrogel matrix for microarray and biosensor applications: an imaging SPR study.

A biosensor matrix based on UV-initiated graft copolymerized poly(ethylene glycol) methacrylate and 2-hydroxyethyl methacrylate has been studied using imaging surface plasmon resonance (iSPR). By using a photo mask and a programmable shutter to vary the exposure time laterally, a gradient of matrix spots with physical thicknesses ranging from a few to tens of nanometers was generated. To maximize the dynamic range, imaging SPR was employed in wavelength interrogation mode.

Photografted poly(ethylene glycol) matrix for affinity interaction studies.

A poly(ethylene glycol) (PEG)-based matrix for studies of affinity interactions is developed and demonstrated. The PEG matrix, less than 0.1 microm thick, is graft copolymerized onto a cycloolefin polymer from a mixture of PEG methacrylates using a free radical reaction initiated by UV light at 254 nm.

Glucocorticoids increase C/EBPbeta activity in the lung epithelium via phosphorylation.

Glucocorticoids are widely prescribed anti-inflammatory drugs used for the treatment of many inflammatory lung disorders. However, much still remains unknown about their molecular mechanisms of action. We have previously shown that glucocorticoid-induced transcription in the lung epithelial cell line NCI-H441 is mediated via C/EBP sites in the promoters of target genes, and is likely to involve the transcription factors C/EBPbeta and C/EBPdelta.

Decreased serum levels of clara cell secretory protein (CC16) are associated with bronchiolitis obliterans and may permit early diagnosis in patients after allogeneic stem-cell transplantation.

Background: Bronchiolitis obliterans (BO) is a common complication and is associated with high mortality after allogeneic stem-cell transplantation (SCT). Early diagnosis of BO may improve outcome. Low levels of Clara cell secretory protein (CC16) have previously been associated with BO in lung transplant recipients.

Decreased CCAAT/enhancer binding protein transcription factor activity in chronic bronchitis and COPD.

Background: CCAAT/enhancer binding proteins (C/EBPs) are key regulators of cell differentiation and linked processes such as proliferation, apoptosis, and gene expression in several organs. C/EBPs are also central for inflammatory responses and infectious defenses, but so far little is known of their role in lung diseases. Chronic bronchitis (CB) and COPD are common smoking-associated lung diseases involving the airway epithelium.

Characterization and expression of the gene encoding membralin, an evolutionary conserved protein expressed in the central nervous system.

We have identified a novel gene that encodes an evolutionary conserved protein that we name membralin since it contains multiple transmembrane regions. The human gene C19orf6 localizes to chromosome 19p13.3.

Decreased serum and bronchoalveolar lavage levels of Clara cell secretory protein (CC16) is associated with bronchiolitis obliterans syndrome and airway neutrophilia in lung transplant recipients.

Background: The major hinderance for long-term survival after lung transplantation is chronic rejection in the form of bronchiolitis obliterans syndrome (BOS). BOS is a fibrosing process in the small airways causing irreversible airway obstruction. BOS is associated with increased oxidative burden and activation of inflammatory and growth-stimulating mediators.