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Risk assessment of false-positive quantitative real-time PCR results in food, due to detection of DNA originating from dead cells

Real-time PCR technology is increasingly used for detection and quantification of pathogens in food samples. A main disadvantage of nucleic acid detection is the inability to distinguish between signals originating from viable cells and DNA released from dead cells. In order to gain knowledge concerning risks of false-positive results due to detection of DNA originating from dead cells, quantitati

Rapid production of cellulase-free xylanases by solventogenic Clostridia from rumen

Xylanases without contaminating cellulases are produced by a wide variety of aerobic bacteria and fungi but anaerobic organisms producing such enzymes are rare. Clostridial species viz., Clostridium beijerinckii LU-1, C. acetobutylicum LU-1, C. butyricum and C. bifermentans LU-1 isolated from rumen produced xylanase (E.C. 3.2.1.8) of 1.5-4.2 U/ml on oat spelt xylan as sole carbon source. Cellulose

Stent Thrombosis in Sweden A Report From the Swedish Coronary Angiography and Angioplasty Registry

Background-The objective was to evaluate the role of risk factors and stent type for stent thrombosis (ST) using a large real world registry. Methods and Results-We evaluated all consecutive coronary stent implantations in Sweden from May 1, 2005, to June 30, 2007. All cases of ST, documented in the Swedish coronary angiography and angioplasty registry until September 21, 2008, were analyzed. ST w

Islet amyloid polypeptide inhibits glucagon release and exerts a dual action on insulin release from isolated islets.

We have studied the influence of a wide concentration range of islet amyloid polypeptide (IAPP) on both glucagon and insulin release stimulated by various types of secretagogues. In an islet incubation medium devoid of glucose, the rate of glucagon release being high, we observed a marked suppressive action by low concentrations of IAPP, 10−10 and 10−8 M, on glucagon release. Similarly, glucagon r

Low-cost evaluation of the exchange Fock matrix from Cholesky and density fitting representations of the electron repulsion integrals

The authors propose a new algorithm, "local K" (LK), for fast evaluation of the exchange Fock matrix in case the Cholesky decomposition of the electron repulsion integrals is used. The novelty lies in the fact that rigorous upper bounds to the contribution from each occupied orbital to the exchange Fock matrix are employed. By formulating these inequalities in terms of localized orbitals, the scal

Identification of the probable inhibitory reactive sites of the cysteine proteinase inhibitors human cystatin C and chicken cystatin

When an excess of human cystatin C or chicken cystatin was mixed with papain, an enzyme-inhibitor complex was formed immediately. The residual free cystatin was then progressively converted to a form with different electrophoretic mobility and chromatographic properties. The modified cystatins were isolated and sequenced, showing that there had been cleavage of a single peptide bond in each molecu

TGF beta receptor II gene deletion in leucocytes prevents cerebral vasculitis in bacterial meningitis

In bacterial meningitis, chemokines lead to recruitment of polymorphonuclear leucocytes (PMN) into the CNS. At the site of infection in the subarachnoid space, PMN release reactive oxygen species, reactive nitrogen intermediates (RNI) and interleukin-1 beta (IL-1 beta). Although these immune factors assist in clearance of bacteria, they also result in neuronal injury associated with meningitis. Tr

Expansion of signal pathways in the ectomycorrhizal fungus Laccaria bicolor- evolution of nucleotide sequences and expression patterns in families of protein kinases and RAS small GTPases.

* The ectomycorrhizal fungus Laccaria bicolor has the largest genome of all fungi yet sequenced. The large genome size is partly a result of an expansion of gene family sizes. Among the largest gene families are protein kinases and RAS small guanosine triphosphatases (GTPases), which are key components of signal transduction pathways. * Comparative genomics and phylogenetic analyses were used to e

Sex-specific associative learning cues and inclusive fitness benefits in the Seychelles warbler

In cooperative, breeding vertebrates, indirect fitness benefits would be maximized by subordinates that accurately assess their relatedness to group offspring and preferentially help more closely related kin. In the Seychelles warbler (Acrocephalus sechellensis), we found a positive relationship between subordinate-nestling kinship (determined using microsatellite marker genotypes) and provisionin

The successional change of hollow oaks affects their suitability for an inhabiting beetle, Osmoderma eremita

We assessed the presence/absence and population size of a threatened beetle, Osmoderma eremita, inhabiting hollow oaks (Quercus robur). Population sizes varied widely between trees (10% of the hollow trees hosted two thirds of the individuals), and increased with the volume of wood mould (= loose material of dead wood) and the height of the entrances. Population density (number of adult beetles pe

Calculation of bound and resonant donor states of GaAs in a magnetic field

The effect of a magnetic field on the energy spectrum of a hydrogenic impurity is investigated using a basis expansion technique. Several excited impurity states, of which some are resonant, are found. Lifetimes are calculated and, by including an electric field, we are able to explain forbidden but experimentally observed optical transitions. (C) 2004 Elsevier Ltd. All rights reserved.

Ammonium and methylamine transport by the ectomycorrhizal fungus Paxillus involutus and ectomycorrhizas

Using [C-14]methylamine as an analogue of ammonium, the kinetics and the energetics of NH: transport were studied in the ectomycorrhizal fungus, Paxillus involutus (Batsch) Fr. The apparent half-saturation constant (K-m) and the maximum uptake rate (V-max) for the carrier-mediated transport derived from the Eadie-Hofstee transformation were 180 mu M and 380 nmol (mg dry wt)(-1) min(-1,) respective

Foraging and mate-finding in the silver Y moth, Autographa gamma (Lepidoptera : Noctuidae) under the risk of predation

Animal foraging and reproductive behaviour is influenced by other simultaneous demands such as predator avoidance. The trade-offs between these demands may depend on sex or mating experience. This study demonstrates that the olfactory-mediated foraging and mate-seeking behaviours in the silver Y moths, Autographa gamma, are affected by auditory cues mimicking their bat predators. Both males and fe

The effect of silver ions and chlorine on the survival of Staphylococcus aureus and Bacillus cereus in dishwater

This paper investigates the effect of chlorine and silver ion solutions on the survival of Bacillus cereus (vegetative phase) and Staphylococcus aureus in batch cultures, representing dishwater. Dishwater contains organic matter and bacteria and bacterial activities are partly reduced by high pH (11-12) and temperature (55-65 degrees C) in professional and domestic dishwashers. in manual dishwashi

A general theory of environmental noise in ecological food webs.

ABSTRACT We examine the effects of environmental noise on populations that are parts of simple two-species food webs. We assume that the species are strongly interacting and that one or the other population is affected by the noise signal. Further assuming that a stable equilibrium with positive population densities exists, we are able to perform a complete frequency analysis of the system. If onl