Phenological shifts assist colonisation of a novel environment in a range‐expanding raptor

In a rapidly changing world understanding the capacity of populations to adapt to novel environments is increasingly urgent. Timing of breeding can be a highly flexible trait and adjustments in this trait can potentially buffer populations from climate change and facilitate the colonisation of new environments. Recent range‐expansions into novel climatic regimes provide a valuable opportunity to investigate the implications of plasticity in timing of breeding for population processes. Black sparrowhawks have recently colonised the Cape Peninsula of South Africa where they experience dramatically different weather patterns to those in their historical range. These include a total reversal in the rainfall regime, with the majority of rain falling in the winter as opposed to the summer months. We investigate the breeding phenology of black sparrowhawks in relation to both regional and local climate variation and, using a long‐term dataset, explore the implications of phenological shifts for reproductive success and population growth following colonisation. In the recently colonised Cape Peninsula the breeding season began up to three months earlier than within their historical range and these early breeding attempts produced more offspring. Population models suggested that this adjustment assisted the colonisation of the Cape Peninsula, reducing the probability of extinction by 23%. Contrary to expectations, we found little support for the hypothesis that black sparrowhawks were responding to local variation in rainfall. We suggest that shifts in breeding phenology may be driven in part by other novel processes, such as interspecific competition for nest sites and lower temperatures during late summer. These results provide insight into the processes that facilitated the colonisation of a novel climatic regime highlighting the potential role of a diverse range of factors.     

Reference signal extraction from corrupted ECG using wavelet decomposition for MRI sequence triggering: application to small animals

Background  

Present developments in Nuclear Magnetic Resonance (NMR) imaging techniques strive for improved spatial and temporal resolution performances. However, trying to achieve the shortest gradient rising time with high intensity gradients has its drawbacks: It generates high amplitude noises that get superimposed on the simultaneously recorded electrophysiological signals, needed to synchronize moving organ images. Consequently, new strategies have to be developed for processing these collected signals during Magnetic Resonance Imaging (MRI) examinations. The aim of this work is to extract an efficient reference signal, from an electrocardiogram (ECG) that was contaminated by the NMR artefacts. This may be used for image triggering and/or cardiac rhythm monitoring.     

Bradykinin receptor 2 extends inflammatory cell recruitment in a model of acute gouty arthritis

The aim of this study was determine the effect of bradykinin receptor antagonism on MSU crystal-induced chemokine production and leukocyte recruitment. Mice were injected intraperitoneally with monosodium urate (MSU) crystals ± bradykinin B1- or B2 receptor antagonists, Des-Arg-HOE-140 and HOE-140, respectively. MSU crystal-induced chemokine production and leukocyte recruitment in the peritoneum were measured over 24h and B1 and B2 receptor expression on leukocytes and peritoneal membrane was determined by flow cytometry and fluorescence microscopy. Data analysis showed that only B2 receptor antagonism decreased monocyte and neutrophil infiltration 24 h post MSU crystal administration. Decreased leukocyte infiltration was associated with reduced monocyte (CCL2) chemokine levels. MSU crystal-induced damage to the surrounding visceral membrane was also attenuated in the presence of B2 receptor antagonism. Together, these data show that bradykinin receptor 2 plays a role in maintaining MSU crystal-induced leukocyte infiltration and membrane permeability and identify the B2 receptor as a potential therapeutic target for managing inflammation in gout.     

Isolation and characterization of the mating-type idiomorphs from the wheat septoria leaf blotch fungus Mycosphaerella graminicola

Both mating-type loci from the wheat septoria leaf blotch pathogen Mycosphaerella graminicola have been cloned and sequenced. The MAT1-2 gene was identified by screening a genomic library from the MAT1-2 isolate IPO94269 with a heterologous probe from Tapesia yallundae. The MAT1-2 idiomorph is 2772 bp and contains a single gene encoding a putative high-mobility-group protein of 394 amino acids. The opposite idiomorph was obtained from isolate IPO323, which has the complementary mating type, by long-range PCR using primers derived from sequences flanking the MAT1-2 idiomorph. The MAT1-1 locus is 2839 bp in size and contains a single open reading frame encoding a putative alpha1-domain protein of 297 amino acids. Within the nonidiomorphic sequences, homology was found with palI, encoding a membrane receptor from Aspergillus nidulans, and a gene encoding a putative component of the anaphase-promoting complex from Schizosaccharomyces pombe and a DNA-(apurinic or apyrimidinic) lyase from S. pombe. For each of the MAT genes specific primers were designed and tested on an F1 mapping population that was generated from a cross between IPO323 and IPO94269. An absolute correlation was found between the amplified allele-specific fragments and the mating type as determined by backcrosses of each F1 progeny isolate to the parental isolates. The primers were also used to screen a collection of field isolates in a multiplex PCR. An equal distribution of MAT1-1 and MAT1-2 alleles was found for most geographic origins examined.     

Raw and steam-pelleted cassava,sweet potato and yam cayenensis as starch sources for ruminant and chicken diets

Three tropical tubers, raw or processed by steam-pelleting, were studied in the rumen in vitro or in the chicken in vivo in order to determine the effects of the nature and of the treatment of the tubers on urea utilization by rumen microflora, starch breakdown in the crop and the performance of growing chickens.Starch of cassava (Manihot utilissima) and of sweet potato (Ipomea batata) is characterised by an X-ray diffraction pattern of the A-type and is therefore similar to starch of cereals. In vitro these starches were well broken down in the presence of α-amylase from B. subtilis, and were good sources of energy for rumen microbial growth; in vivo they were completely digested by growing chickens. Compared to cassava, the fermentation of sweet potato in rumen and crop led to increased acidity. The cassava diet gave a better nitrogen retention and growth performance associated with higher food intake.In contrast, starch of yam (Dioscorea cayenensis) which is characterized by an X-ray diffraction pattern of the B-type, and by large granules like potato starch, was less susceptible to α-amylase and promoted lower microbial proteosynthesis in vitro. Starch from a yam diet was more slowly degraded in the crop and its overall digestibility was only 83%. Yam reduced feed intake and gave lower nitrogen retention and lower food conversion ratio and consequently poor growth.The steam-pelleting treatment increased starch availability and permitted better urea utilization by rumen microflora. It improved N retention and feed efficiency of chicken diets, although not significantly. The greatest effect of the treatment was observed with yam.In conclusion, the digestibility of a given starch seems to be related to its structure, characterized by the type of X-ray diffraction pattern, which could be a help in tuber selection for animal nutrition. Simple processing such as steam-pelleting may improve the nutritive value of a tuber, especially when its starch has a B-type crystallinity.     

BRAIN CONCENTRATIONS OF BIOGENIC AMINES AND THEIR METABOLITES IN TWO TYPES OF PYROGEN-INDUCED FEVER IN RABBITS

The effects of two bacterial pyrogens (gonococcus vaccine and E. coli lipopolysaccharide) on brain and CSF concentrations of the biogenic amines and their major metabolites were compared in rabbits. Both pyrogens induced a similar fever, but only the lipopolysaccharide elicited marked biochemical alterations. The main changes observed were: a decrease in the concentrations of acid metabolites of dopamine during the upward course of the first peak of fever; a decrease in the hypothalamic concentrations of noradrenaline at the second peak of fever; a general increase in the metabolites of biogenic amines around the second peak and during the fall of fever. The results led to the conclusion that no significant correlation exists between body temperature and brain amine levels in rabbits. The alterations observed could be a consequence of the fever itself when considered in terms of trauma to the organism.     

Use of [Cit312,314] filaggrin (306–324) analogue for the diagnosis of rheumatoid arthritis. Conformational study by circular dichroism and fourier transformed infrared spectroscopy

Summary Antifilaggrin autoantibodies (AFA) have described to be the most specific markers of rheumatoid arthritis (RA) and epitopes containing citrulline within the sequence of filaggrin identified as major antigenic sites recognised by AFA. In this paper we confirm that citrulline is an essential constituent of filaggrin related antigenic determinants recognised by RA specific autoantibodies, thus having an important role for the development of filaggrin peptides based serological tests. Moreover, we describe our findings on the comparative conformational analysis of filaggrin (306–324) peptide sequence and an analogue in which two arginines were simultaneously substituted by citrulline carried out by Circular Dichroism (CD) and Fourier-Transform Infrared Spectroscopy (FTIR). Results might contribute to the understanding of the structural features that may be important to explain the enhanced binding characteristics of citrullinated peptides to the autoantibodies in rheumatoid arthritis.