Linking the pattern to the mechanism: How an introduced mammal facilitates plant invasions

Non‐native mammals that are disturbance agents can promote non‐native plant invasions, but to date there is scant evidence on the mechanisms behind this pattern. We used wild boar (Sus scrofa) as a model species to evaluate the role of non‐native mammals in promoting plant invasion by identifying the degree to which soil disturbance and endozoochorous seed dispersal drive plant invasions. To test if soil disturbance promotes plant invasion, we conducted an exclosure experiment in which we recorded emergence, establishment and biomass of seedlings of seven non‐native plant species planted in no‐rooting, boar‐rooting and artificial rooting patches in Patagonia, Argentina. To examine the role of boar in dispersing seeds we germinated viable seeds from 181 boar droppings and compared this collection to the soil seed bank by collecting a soil sample adjacent to each dropping. We found that both establishment and biomass of non‐native seedlings in boar‐rooting patches were double those in no‐rooting patches. Values in artificial rooting patches were intermediate between those in boar‐rooting and no‐rooting treatments. By contrast, we found that the proportion of non‐native seedlings in the soil samples was double that in the droppings, and over 80% of the germinated seeds were native species in both samples. Lastly, an effect size test showed that soil disturbance by wild boar rather than endozoochorous dispersal facilitates plant invasions. These results have implications for both the native and introduced ranges of wild boar, where rooting disturbance may facilitate community composition shifts.     

Vitamin E ingestion improves several immune functions in elderly men and women

The effects of diet supplementation with the antioxidant vitamin E (200 mg daily) on several blood neutrophil, lymphocyte and natural killer cell functions have been investigated in healthy elderly men and women before supplementation, after 3 months of supplementation and 6 months after the end of supplementation (post-supplementation). In parallel, samples of healthy adult men and women were used as age controls. In elderly men and women, an impairment of immune functions was observed in comparison with the respective adult controls and the intake of vitamin E resulted in a significant enhancement of immune parameters in both elderly men and women, bringing their values close to those in the adults. These effects were not found in post-supplementation samples in several but not in all functions. The present findings suggest that supplementation with vitamin E can produce an improvement of immune functions and therefore of health in aged people.     

Prevention of tubulin/aldose reductase association delays the development of pathological complications in diabetic rats

Journal of Physiology and Biochemistry - In recent studies, we found that compounds derived from phenolic acids (CAFs) prevent the formation of the tubulin/aldose reductase complex and,...     

Plasma metabolite levels predict bird growth rates: A field test of model predictive ability

Bird growth rates are usually derived from nonlinear relationships between age and some morphological structure, but this procedure may be limited by several factors. To date, nothing is known about the capacity of plasma metabolite profiling to predict chick growth rates. Based on laboratory-trials, we here develop predictive logistic models of body mass, and tarsus and wing length growth rates in Gull-billed Tern Gelochelidon nilotica chicks from measurements of plasma metabolite levels at different developmental stages. The predictive model obtained during the fastest growth period (at the age of 12 days) explained 65-68% of the chicks' growth rates, with fasting triglyceride level explaining most of the variation in growth rate. At the end of pre-fledging period, β-hydroxybutyrate level was also a good predictor of growth rates. Finally, we carried out a field test to check the predictive capacity of the models in two colonies of wild Gull-billed Tern, comparing field-measured and model-predicted growth rates between groups. Both, measured and predicted growth rates, matched statistically. Plasma metabolite levels can thus be applied in comparative studies of chick growth rates when semi-precocial birds can be captured only once.     

Nocardiosis in Mediterranean bivalves: First detection of Nocardia crassostreae in a new host Mytilus galloprovincialis and in Ostrea edulis from the Gulf of Naples (Italy)

In this work M. galloprovincialis and O. edulis specimens were surveyed for a pathological study in the Gulf of Naples (Mediterranean sea, Campania Region, southern Italy). Clusters of Nocardia sp.-like cells were observed in histological slides. PCR amplification, sequencing and in situ hybridization were carried out in order to corroborate Nocardia species identification for both hosts. Blast results showed a 99% of maximum identity with Nocardia crassostreae sequences in Genbank. This is the first report of N. crassostreae in the new host M. galloprovincialis and, in a new area, the Mediterranean Sea.     

A high-throughput SNP marker system for parental polymorphism screening, and diversity analysis in common bean (Phaseolus vulgaris L.)

Single nucleotide polymorphism (SNP) detection has become a marker system of choice, because of the high abundance of source polymorphisms and the ease with which allele calls are automated. Various technologies exist for the evaluation of SNP loci and previously we validated two medium throughput technologies. In this study, our goal was to utilize a 768 feature, Illumina GoldenGate assay for common bean (Phaseolus vulgaris L.) developed from conserved legume gene sequences and to use the new technology for (1) the evaluation of parental polymorphisms in a mini-core set of common bean accessions and (2) the analysis of genetic diversity in the crop. A total of 736 SNPs were scored on 236 diverse common bean genotypes with the GoldenGate array. Missing data and heterozygosity levels were low and 94 % of the SNPs were scorable. With the evaluation of the parental polymorphism genotypes, we estimated the utility of the SNP markers in mapping for inter-genepool and intra-genepool populations, the latter being of lower polymorphism than the former. When we performed the diversity analysis with the diverse genotypes, we found Illumina GoldenGate SNPs to provide equivalent evaluations as previous gene-based SNP markers, but less fine-distinctions than with previous microsatellite marker analysis. We did find, however, that the gene-based SNPs in the GoldenGate array had some utility in race structure analysis despite the low polymorphism. Furthermore the SNPs detected high heterozygosity in wild accessions which was probably a reflection of ascertainment bias. The Illumina SNPs were shown to be effective in distinguishing between the genepools, and therefore were most useful in saturation of inter-genepool genetic maps. The implications of these results for breeding in common bean are discussed as well as the advantages and disadvantages of the GoldenGate system for SNP detection.     

Manipulating the bioactivity of hydroxyapatite nano-rods structured networks: Effects on mineral coating morphology and growth kinetic

Background

Nano-hydroxyapatite particles have better bioactivity than the coarse crystals. So, they can be utilized for engineered tissue implants with improved efficiency over other materials. The development of materials with specific bioactive characteristics is still under investigation.

Methods

The surface properties of four hydroxyapatite materials templated by different micelle-polymer structured network are studied. The synergistic interaction of each block copolymer in contact with CTAB rod-like micelles results in crystalline HAp nano-rods of 25–50 nm length organized in hierarchical structures with different micro-rough characteristics.

Results

It was observed that the material in vitro bioactivity strongly depends on the surface structure while in a minor extent on their Ca/P ratio. So, MIII and MIV materials with Skewness parameter R_sk > 2.62 favored the formation on their surfaces of net-like phase with a high growth kinetic constant; while MI and MII (R_sk ≤ 2.62) induced the appearance of spherulitic-like structures and a growth rate 1.75 times inferior. Material biocompatibility was confirmed by interaction with rat calvarial osteoblasts.

Conclusions

The different structures growth is attributed to a dissimilar matching of crystal planes in the material and the apatite layer formed. In specific synthesis conditions, a biocompatible material with a Ca/P ratio close to that for the trabecular bone and a morphology that are considered essential for bone-bonding was obtained.

General significance

The creation of implantable devices with a specific bioactive characteristic may be useful to manipulate the attachment of cells on mineral coating directly affecting the stability and life of the implant.     

Detection of Soluble Antigen and DNA of Trypanosoma cruzi in Urine Is Independent of Renal Injury in the Guinea Pig Model

The diagnosis of Chagas disease in humans is generally limited to the detection of specific antibodies. Detection of T. cruzi antigens in urine has been reported previously, but is not used in the diagnosis. In this study, soluble T. cruzi antigens and DNA were detected in urine samples and were associated with kidney injury and systemic detection of the parasite. We used 72 guinea pigs infected with T. cruzi Y strain and 18 non-infected guinea pigs. Blood, kidney, heart and urine samples were collected during the acute phase and chronic phase. Urine samples were concentrated by ultrafiltration. Antigens were detected by Western Blot using a polyclonal antibody against trypomastigote excretory-secretory antigen (TESA). T. cruzi DNA was detected by PCR using primers 121/122 and TcZ1/TcZ2. Levels of T. cruzi DNA in blood, heart and kidney were determined by quantitative PCR. T. cruzi antigens (75 kDa, 80 kDa, 120 kDa, 150 kDa) were detected in the acute phase (67.5%) and the chronic phase (45%). Parasite DNA in urine was detected only in the acute phase (45%). Kidney injury was characterized by high levels of proteinuria, kidney injury molecule-1 (KIM-1) and urea, and some histopathological changes such as inflammation, necrosis, fibrosis and scarce parasites. The detection of antigens and DNA in urine was associated with the presence of parasite DNA in blood and heart and with high levels of parasite DNA in blood, but not with the presence of parasite in kidney or kidney injury. These results suggest that the detection of T. cruzi in urine could be improved to be a valuable method for the diagnosis of Chagas disease, particularly in congenital Chagas disease and in immunocompromised patients.     

MiR-7 Triggers Cell Cycle Arrest at the G1/S Transition by Targeting Multiple Genes Including Skp2 and Psme3

MiR-7 acts as a tumour suppressor in many cancers and abrogates proliferation of CHO cells in culture. In this study we demonstrate that miR-7 targets key regulators of the G1 to S phase transition, including Skp2 and Psme3, to promote increased levels of p27^KIP and temporary growth arrest of CHO cells in the G1 phase. Simultaneously, the down-regulation of DNA repair-specific proteins via miR-7 including Rad54L, and pro-apoptotic regulators such as p53, combined with the up-regulation of anti-apoptotic factors like p-Akt, promoted cell survival while arrested in G1. Thus miR-7 can co-ordinate the levels of multiple genes and proteins to influence G1 to S phase transition and the apoptotic response in order to maintain cellular homeostasis. This work provides further mechanistic insight into the role of miR-7 as a regulator of cell growth in times of cellular stress.     

EDA-Containing Fibronectin Increases Proliferation of Embryonic Stem Cells

Embryonic stem cells (ESC) need a set of specific factors to be propagated. They can also grow in conditioned medium (CM) derived from a bovine granulosa cell line BGC (BGC-CM), a medium that not only preserves their main features but also increases ESC´s proliferation rate. The mitogenic properties of this medium were previously reported, ascribing this effect to an alternative spliced generated fibronectin isoform that contains the extra domain A (FN EDA⁺). Here, we investigated if the FN EDA⁺ isoform increased proliferation of mouse and human ES cells. We analyzed cell proliferation using conditioned media produced by different mouse embryonic fibroblast (MEF) lines genetically engineered to express FN constitutively including or excluding the EDA domain (FN EDA^-), and in media supplemented with recombinant peptides containing or not the EDA. We found that the presence of EDA in the medium increased mouse and human ESC’s proliferation rate. Here we showed for the first time that this FN isoform enhances ESC’s proliferation. These findings suggest a possible conserved behavior for regulation of ES cells proliferation by this FN isoform and could contribute to improve their culturing conditions both for research and cell therapy.