Cubicle Refusal in Norwegian Dairy Herds

In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal), a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7–118). More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0–55%). Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R² = 0.05), while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51).     

Behavioural acclimation to cameras and observers in coral reef fishes

Observer presence can bias behavioural studies of animals in both the wild and the laboratory. Despite existing evidence for significant observer effects across several taxa, little is known about the minimum periods of acclimation that should precede behavioural observations. To date, most studies either do not report any acclimation periods or include a non‐specific period without empirically quantifying its appropriateness. Here, we conducted in situ behavioural observations of two species of demersal coral reef fishes using cameras and/or observers to examine the biases associated with either approach. For both treatments, we generated 25 min time series of a number of vigilance‐associated behaviours (i.e., distance from shelter and mate, time out of shelter, swimming activity) and estimated the point of acclimation using changepoint analysis. In the camera trials, acclimation in both species appeared to occur between 2 and 7 min for different behaviours. When an observer was present, however, no apparent acclimation occurred until the observer left the area. Overall, our findings demonstrate that (i) behavioural studies of wild fishes conducted by an observer may be biased due to permanent observer effects, and (ii) when using video equipment, a species‐ and behaviour‐specific acclimation period should precede behavioural scoring.     

Autoantibody systems in rheumatoid arthritis: specificity, sensitivity and diagnostic value

The diagnosis of rheumatoid arthritis (RA) is primarily based on clinical symptoms, so it is often difficult to diagnose RA in very early stages of the disease. A disease-specific autoantibody that could be used as a serological marker would therefore be very useful. Most autoimmune diseases are characterized by a polyclonal B-cell response targeting multiple autoantigens. These immune responses are often not specific for a single disease. In this review, the most important autoantibody/autoantigen systems associated with RA are described and their utility as a diagnostic and prognostic tool, including their specificity, sensitivity and practical application, is discussed. We conclude that, at present, the antibody response directed to citrullinated antigens has the most valuable diagnostic and prognostic potential for RA.     

Bestimmung von deoxynivalenol mittels LC - MS/MS (Tandem Massenspektrometrie)

A sensitive and selective method using high-performance liquid chromatography in combination with atmospheric pressure chemical ionization tandem mass spetrometry (LC-APCI-MS/MS) has been developed for the determination of Deoxynivalenol (DON) in trace levels. The extract was purified with a MultiSep? column followed by the Vicam? DON immunoaffinity column. Quantification is based on an external standard method using positive Multiple Reaction Monitoring (MRM). The limit of detection was 5 μg/kg with a signal to noise ratio of 3:1.     

Rate and topography of peptidoglycan synthesis during cell division in Escherichia coli: concept of a leading edge.

The rate at which the peptidoglycan of Escherichia coli is synthesized during the division cycle was studied with two methods. One method involved synchronization of E. coli MC4100 lysA cultures by centrifugal elutriation and subsequent pulse-labeling of the synchronously growing cultures with [meso-3H]diaminopimelic acid ([3H]Dap). The second method was autoradiography of cells pulse-labeled with [3H]Dap. It was found that the peptidoglycan is synthesized at a more or less exponentially increasing rate during the division cycle with a slight acceleration in this rate as the cells start to constrict. Apparently, polar cap formation requires synthesis of extra surface components, presumably to accommodate for a change in the surface-to-volume ratio. Furthermore, it was found that the pool size of Dap was constant during the division cycle. Close analysis of the topography of [3H]Dap incorporation at the constriction site revealed that constriction proceeded by synthesis of peptidoglycan at the leading edge of the invaginating cell envelope. During constriction, no reallocation of incorporation occurred, i.e., the incorporation at the leading edge remained high throughout the process of constriction. Impairment of penicillin-binding protein 3 by mutation or by the specific beta-lactam antibiotic furazlocillin did not affect [3H]Dap incorporation during initiation of constriction. However, the incorporation at the constriction site was inhibited in later stages of the constriction process. It is concluded that during division at least two peptidoglycan-synthesizing systems are operating sequentially.     

Blocking of the fibrinolytic antiactivator by substituted benzoates

The effects of substituted benzoates on the inhibition of the urokinase-activation of profibrinolysin by the fibrinolytic antiactivator in plasma were investigated. It was found that substituted benzoates block the inhibition of urokinase by plasma fibrinolytic antiactivators. The urokinase which is bound by the antiactivator appears to be released and hence is available to activate profibrinolysin to fibrinolysin. The nitrobenzoates were the most effective of all compounds tested.     

RESPIRATION AND PROTEIN SYNTHESIS IN ESCHERICHIA COLI MEMBRANE-ENVELOPE FRAGMENTS : IV. Chemical and Cytological Characterization and Biosynthetic Capabilities of Fragments Obtained by Mild Procedures

Membrane-envelope fragments have been isolated from Escherichia coli by comparatively mild techniques. The use of DNAase, RNAase, detergents, sonication, lysozyme, and ethylenediaminetetraacetate were avoided in the belief that rather delicate, but metabolically important, associations may exist between the plasma membrane and various cytoplasmic components. The membrane-envelope fragments have been characterized in terms of their content of major chemical components as well as their electron microscope appearance. Fractions containing membrane-envelope fragments were found to possess appreciable DNA- and protein-synthesizing activities. The fragments were rich in membrane content as determined by reduced nicotinamide adenine dinucleotide (NADH) oxidase activity and deficient in soluble components as measured by NADH dehydrogenase activity. The particulate fraction obtained between 20,000 g and 105,000 g and usually considered a ribosomal fraction was rich in membrane content and had a relatively high capacity for DNA synthesis. Envelope fragments sedimenting at 20,000 g attained very high levels of incorporation of amino acids into protein.     

Fracture Faces in the Cell Envelope of Escherichia coli

Freeze-fracturing of Escherichia coli cells in the presence of 30% (v/v) glycerol resulted in a double cleavage of the cell envelope exposing two convex and two concave fracture faces ([Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text]) with characteristic patterns. Complementary replicas revealed the relationship of the fracture faces to their corresponding fracture planes. The inner fracture plane splits the plasma membrane at one particular level. Apparently the outer fracture plane was located in the outer part of the wall, as it was separated by a layer ([Formula: see text]) from the fractured profile (CW1) presumably corresponding to the murein layer. The outer fracture plane did alternate toward the cell periphery, exposing complementary smooth areas ([Formula: see text] and [Formula: see text]). When cells were freeze-fractured in the absence of glycerol, the outer cell surface appeared as an etching face rather than a fracture face. A schematic representation of the relative location of the different fracture faces in the E. coli cell envelope is given.     

Fermentation of glutamate by Selenomonas acidaminophila sp. nov.

From an anaerobic digester a novel type of strictly anaerobic, Gram-negative, non-sporeforming mesophilic bacterium was isolated. The cells were curved rods, motile by means of lateral flagella and contained b- and c-type cytochromes. The G+C content of the DNA was 48.0±1.0 mol%. The isolate was able to ferment only glutamate, aspartate, lactate and pyruvate. Organic fermentation products were acetate, propionate and succinate. Propionate was probably formed via a reductive succinate pathway. Strain DKglu16 is described as the type strain of a new species, Selenomonas acidaminophila sp. nov., in the family Bacteroidaceae.Abbreviations atm atmosphere - Pa Pascal - SSC standard saline citrate - G+C guanine+cytosine - _max maximum specific growth rate