Imprints of glacial history and current environment on correlations between endemic plant and invertebrate species richness

Aim We evaluate how closely diversity patterns of endemic species of vascular plants, beetles, butterflies, molluscs and spiders are correlated with each other, and to what extent similar environmental requirements or survival in common glacial refugia and comparable dispersal limitations account for their existing congruence. Location Austria. Methods We calculated pairwise correlations among species numbers of the five taxonomic groups in 1405 cells of a 3′ × 5′ raster (c. 35 km²) using the raw data as well as the residuals of regression models that accounted for: (1) environmental variables, (2) environmental variables and the occurrence of potential refugia during the Last Glacial Maximum, or (3) environmental variables, refugia and spatial filters. Results Pairwise cross‐taxonomic group Spearman’s rank correlations in the raw data were significantly positive in most cases, but only moderate (0.3 < ρ < 0.5) to weak (ρ < 0.3) throughout. Correlations were closest between plants and beetles, plants and butterflies, and plants and snails, respectively, whereas the distribution of endemic spiders was largely uncorrelated with those of the other groups. Environmental variables explained only a moderate proportion of the variance in endemic richness patterns, and the response of individual groups to environmental gradients was only partly consistent. The inclusion of refugium locations and the spatial filters increased the goodness of model fit for all five taxonomic groups. Moreover, removing the effects of environmental conditions reduced congruence in endemic richness patterns to a lesser extent than did filtering the influence of refugium locations and spatial autocorrelation, except for spiders, which are probably the least dispersal‐limited of the five groups. Main conclusions The moderate to weak congruence of endemic richness patterns clearly limits the usefulness of a surrogacy approach for designating areas for the protection of regional endemics. On the other hand, our results suggest that dispersal limitations still shape the distributions of many endemic plant, snail, beetle and butterfly species, even at the regional scale; that is, survival in shared refugia and subsequent restricted spread retain a detectable signal in existing correlations. Concentrating conservation efforts on well‐known Pleistocene refugia hence appears to be a reasonable first step towards a strategy for protecting regional endemics of at least the less mobile invertebrate groups.     

Short hairpin RNAs against eotaxin or interleukin‐5 decrease airway eosinophilia and hyper‐responsiveness in a murine model of asthma

Background

Eosinophilia plays the major role in the pathogenesis of asthma and correlates with the up‐regulation of eotaxin, which, together with interleukin (IL)‐5, is important for differentiation, chemo‐attraction, degranulation, and survival of eosinophils in local tissue. In a previous study, we found that administration of lentivirus‐delivered short hairpin RNA (shRNA) to suppress the expression of IL‐5 inhibited airway inflammation. The present study aimed to investigate the role of eotaxin shRNA and the synergistic effect of eotaxin and IL‐5 shRNAs on airway inflammation in an ovalbumin (OVA)‐induced murine model of asthma.

Methods

Lentivirus‐delivered shRNAs were used to suppress the expression of eotaxin and/or IL‐5 in local tissue in an OVA‐induced murine asthma model.

Results

Intra‐tracheal administration of lentivirus containing eotaxin shRNA expressing cassette (eoSEC3.3) efficiently moderated the characteristics of asthma, including airway hyper‐responsiveness, cellular infiltration of lung tissues, and eotaxin and IL‐5 levels in bronchio‐alveolar lavage fluid. Administration of lentiviruses expressing IL‐5 or eotaxin shRNAs (IL5SEC4 + eoSEC3.3) also moderated the symptoms of asthma in a mouse model.

Conclusions

Local delivery of lentiviruses expressing IL‐5 and eotaxin shRNAs provides a potential tool in moderating airway inflammation and also has the potential for developing clinical therapy based on the application of shRNAs of chemokines and cytokines involved in T helper 2 cell inflammation and eosinophilia. Copyright © 2008 John Wiley & Sons, Ltd.     

GRF-induced feeding: Evidence for protein selectivity and opiate involvement

Growth hormone-releasing factor (GRF) is a hypothalamic peptide named for its ability to induce release of growth hormone from the anterior pituitary. GRF also acts as a neurotransmitter in the suprachiasmatic nucleus/medial preoptic area (SCN/MPOA) to stimulate food intake. The purpose of this series of experiments was to explore the nature of GRF-induced feeding, with a particular emphasis on macronutrient selectivity, and to examine the role of opiate activity in the paraventricular nucleus of the hypothalamus (PVN). Chow intake stimulated by GRF microinjection (1 pmol/0.5 μl) into the SCN/MPOA was blocked by injection of methyl-naltrexone (3 μg/0.5 μl) into the PVN. In animals habituated to macronutrient diets (Teklad, WI), GRF preferentially stimulated intake of protein at 2 and 4 h postinjection, whereas it had no effect on carbohydrate intake. Further, this effect was blocked by injection of naloxone (40 nmol/0.5 μl) into the PVN. Microinjection of morphine (0, 1, 10, and 17 μg/0.5 μl) into the PVN also specifically stimulated protein intake at 2 and 4 h postinjection. These results suggest that feeding derived from GRF actions in the SCN/MPOA is macronutrient selective, and is dependent on PVN opiate activity for expression.     

Characterization of microsatellite loci in White‐chinned Petrel (Procellaria aequinoctialis) and cross‐amplification in six other procellariiform species

Six polymorphic dinucleotide microsatellite loci were isolated and characterized from the White‐chinned Petrel Procellaria aequinoctialis, using a degenerate primer and PCR‐based technique to construct and screen an enriched genomic library. Preliminary data on three populations show heterozygosity levels ranging from 0.22 to 0.67 and allele numbers from three to nine. Preliminary data also suggest genetic distance between these three populations (F_ST 0.088). Cross‐species amplification of these six microsatellite loci and one further locus were tested in six other procellariiform species of the genus Procellaria, Macronectes, Thalassarche and Diomedea.     

ABC as a flexible framework to estimate demography over space and time: some cons,many pros

The analysis of genetic variation to estimate demographic and historical parameters and to quantitatively compare alternative scenarios recently gained a powerful and flexible approach: the Approximate Bayesian Computation (ABC). The likelihood functions does not need to be theoretically specified, but posterior distributions can be approximated by simulation even assuming very complex population models including both natural and human‐induced processes. Prior information can be easily incorporated and the quality of the results can be analysed with rather limited additional effort. ABC is not a statistical analysis per se, but rather a statistical framework and any specific application is a sort of hybrid between a simulation and a data‐analysis study. Complete software packages performing the necessary steps under a set of models and for specific genetic markers are already available, but the flexibility of the method is better exploited combining different programs. Many questions relevant in ecology can be addressed using ABC, but adequate amount of time should be dedicated to decide among alternative options and to evaluate the results. In this paper we will describe and critically comment on the different steps of an ABC analysis, analyse some of the published applications of ABC and provide user guidelines.     

Combined effect of X‐ray radiation and static magnetic fields on reactive oxygen species in rat lymphocytes in vitro

The aim of this study was to investigate the effect of static magnetic fields (SMF) on reactive oxygen species induced by X‐ray radiation. The experiments were performed on lymphocytes from male albino Wistar rats. After exposure to 3 Gy X‐ray radiation (with a dose rate of 560 mGy/min) the measurement of intracellular reactive oxygen species in lymphocytes, using a fluorescent probe, was done before exposure to the SMF, and after 15 min, 1 and 2 h of exposure to the SMF or a corresponding incubation time. For SMF exposure, 0 mT (50 µT magnetic field induction opposite to the geomagnetic field) and 5 mT fields were chosen. The trend of SMF effects for 0 mT was always opposite that of 5 mT. The first one decreased the rate of fluorescence change, while the latter one increased it. Bioelectromagnetics 34:333–336, 2013. © 2012 Wiley Periodicals, Inc.     

Embelin impact on paraquat‐induced lung injury through suppressing oxidative stress,inflammatory cascade,and MAPK/NF‐κB signaling pathway

The current examination was intended to observe the defensive impacts of embelin against paraquat‐incited lung damage in relationship with its antioxidant and anti‐inflammatory action. Oxidative stress marker, like malondialdehyde (MDA), antioxidative enzymes, for example, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH Px), inflammatory cytokines, such as interleukin‐1β (IL‐1β), tumor necrosis factor‐α, and IL‐6, histological examination, and nuclear factor kappa B/mitogen‐activated protein kinase (NF‐κB/MAPK) gene expression were evaluated in lung tissue. Embelin treatment significantly decreased MDA and increased SOD, CAT, and GSH Px. Embelin significantly reduced levels of inflammatory cytokines in paraquat‐administered and paraquat‐intoxicated rats. In addition, embelin suggestively decreased relative protein expression of nuclear NF‐κB p65, p‐NF‐κBp65, p38 MAPK, and p‐p38 MAPKs in paraquat‐intoxicated rats. The outcomes show the impact of embelin inhibitory action on NF‐κB and MAPK and inflammatory cytokines release, and the decrease of lung tissue damage caused by paraquat.     

Patterns of co‐occurrences in a killifish metacommunity are more related with body size than with species identity

Body size may be more important than species identity in determining species interactions and community structure. However, co‐occurrence of organisms has commonly been analysed from a taxonomic perspective and the body size is rarely taken into account. On six sampling occasions, we analysed patterns of killifish co‐occurrences in nestedness (tendency for less rich communities to be subsamples of the richest), checkerboard structure (tendency for species segregation), and modularity (tendency for groups to co‐occur more frequently than random expectation) in a pond metacommunity located in Uruguay. We contrasted co‐occurrence patterns among species and body size‐classes (individuals from different species were combined into size categories). The analysis was performed at two spatial scales: ponds (communities) and sample units within ponds. Observed nestedness was frequently smaller than the null expectation, with significantly greater deviations for body size‐classes than for species, and for sample units than for communities. At the sample unit level, individuals tended to segregate (i.e. clump into a checkerboard pattern) to a larger extent by body size rather than by taxonomy. Modularity was rarely detected, but nevertheless indicated a level of taxonomic organization not evident in nestedness or checkerboard indices. Identification of the spatial scale and organization at which ecological forces determine community structure is a basic requirement for advancement of robust theory. In our study system, these ecological forces probably structured the community by body sizes of interacting organisms rather than by species identities.