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Summary Background Dog dander is an important cause of respiratory allergy but its content of allergenic components is still incompletely known. While Can f 1, 2, 3 and 5 have been studied in detail, only fragmentary information is available on the lipocalin Can f 4. Objective To purify, clone and characterize dog dander allergen Can f 4. Methods Can f 4 was purified from dog dander extract by size exclusion, ion exchange and reverse phase chromatography. A cDNA encoding Can f 4 was cloned and used to produce recombinant Can f 4 in Escherichia coli. A 23 kDa protein from cow dander, displaying cross-reactivity with Can f 4, was purified and identified by amino acid sequencing and mass spectrometry. IgE antibody binding to dog and cow dander extract and to individual dog allergens among 37 dog allergic subjects and 44 pollen allergic controls was studied using ImmunoCAP. Results A dog genome segment containing the Can f 4 gene was bioinformatically identified and enabled the cloning of Can f 4 cDNA. Recombinant Can f 4 displayed close immunological and biochemical similarity to purified natural Can f 4 and bound IgE antibodies from 13/37 (35%) sera of dog allergic subjects. Can f 4 reactive sera showed IgE binding to a 23 kDa protein present in cow dander extract, related to a family of odorant-binding proteins. The dog and cow proteins shared 37% sequence identity and their cross-reactivity was demonstrated by IgE inhibition experiments. Conclusion Recombinant Can f 4 brings the panel of available dog allergens closer to completion and will be important in component-resolved diagnostics in allergy to animal epithelial allergens. Cite this as: L. Mattsson, T. Lundgren, P. Olsson, M. Sundberg and J. Lidholm, Clinical & Experimental Allergy, 2010 (40) 1276–1287.

After a primary traumatic injury, spinal cord tissue undergoes a series of pathobiological changes, including compromised blood-spinal cord barrier (BSCB) integrity. These vascular changes occur over both time and space. In an experimental model of spinal cord injury (SCI), longitudinal dynamic contrast-enhanced MRI (DCE-MRI) studies were performed up to 56 days after SCI to quantify spatial and temporal changes in the BSCB permeability in tissue that did not show any visible enhancement on the post-contrast MRI (non-enhancing tissue). DCE-MRI data were analyzed using a two-compartment pharmacokinetic model. These studies demonstrate gradual restoration of BSCB with post-SCI time. However, on the basis of DCE-MRI, and confirmed by immunohistochemistry, the BSCB remained compromised even at 56 days after SCI. In addition, open-field locomotion was evaluated using the 21-point Basso-Beattie-Bresnahan scale. A significant correlation between decreased BSCB permeability and improved locomotor recovery was observed.

The defects in the zinc selenide crystals with zinc blende structure grown from the melt by the Bridgman method under argon pressure are examined by electron microscopy. The microscopical observations are performed using high voltage, high resolution, and conventional microscopes. Results of investigations of twins, stacking faults, dislocations, precipitates, and pores in ZnSe crystals are presented and discussed. Mittels Elektronenmikroskopie werden die Defekte in Zinkselenidkristallen mit Zinkbleudestruktur, die mit der Bridgmanmethode unter Argondruck aus der Schmelze gezogen werden, untersucht. Die mikroskopischen Beobachtungen werden mittels Hochspannungs-, Hochauflosungsund konventioneller Mikroskopie durchgefuhrt. Ergebnisse von Untersuchungen an Zwillingen, Stapelfehlern, Versetzungen, Prazipitaten und Poren in ZnSe-Kristallen werden mitgeteilt und diskutiert.

High resolution proton decoupled 13C and 31P n.m.r. spectra of bis(diphenylphosphino)acetylene in (CD3)2SO and CDCl3 are analysed as ABX spectra to give the relative chemical shifts of the 13C and 31P nuclei as well as the spin–spin coupling constants 3J(PP) and nJ(PC). The differences in 31P shieldings are due to secondary 13C isotope effects which have been observed to be negligible over more than two bonds.

The reduction of oxygen on rotating disk glassy carbon electrodes was studied in 0.1M HCl. Reproducible single waves with constant limiting currents over a potential range of 0.5V were obtained after the samples were electrochemically treated: anodic polarization at 2.0V vs. SCE and subsequent cathodic reduction. The number of electrons transferred in the oxygen reduction reaction was calculated to be 2.3. The surface of the glassy carbon was examined by XPS at different stages of the electrochemical treatment. After the anodic treatment, the ratio of oxidized carbon vs. graphitic carbon was higher than 1. The predominant oxygen species were carbonyl groups. Following reduction, the surface had an oxidized vs. graphitic carbon ratio below 0.5 with the oxygen distributed between phenolic and carboxylic groups. The role of the chloride ion in the formation of the carbonyl groups is discussed.