Aspects of reproduction and their implications for the conservation of the endangered limpet,Patella ferruginea

Summary

The protandric limpet, Patella ferruginea G., is the most endangered marine species in the Western Mediterranean and is at serious risk of extinction. Nevertheless, its biology and ecology are little known. In the present work, several reproductive aspects are studied. Recruitment take place in June and the largest individuals are the most scarce. The sex ratio is slanted towards the largest sizes, and the species seems to show sex change at sizes from 60 mm upwards, although males can be observed up to 80 mm. There is no correlation between size of oocytes and shell length; however, the larger females contribute greatly to the reproductive event, with high fecundity and GSI values. The mean diameter of oocytes was observed to be 149.78 μm, whereas the heads of spermatozoa were 3.78 μm long. The results of the present study increase the maximum length for males by double that cited in previous literature and highlight the importance of strictly protecting females (i.e., most of the largest individuals, >60 mm), since their population percentage is very low, in order to develop adequate strategies to preserve the species.     

Production of endothelial progenitor cells obtained from human Wharton's jelly using different culture conditions

Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium.     

A chromosome-scale assembly of the bilberry genome identifies a complex locus controlling berry anthocyanin composition

Bilberry (Vaccinium myrtillus L.) belongs to the Vaccinium genus, which includes blueberries (Vaccinium spp.) and cranberry (V. macrocarpon). Unlike its cultivated relatives, bilberry remains largely undomesticated, with berry harvesting almost entirely from the wild. As such, it represents an ideal target for genomic analysis, providing comparisons with the domesticated Vaccinium species. Bilberry is prized for its taste and health properties and has provided essential nutrition for Northern European indigenous populations. It contains high concentrations of phytonutrients, with perhaps the most important being the purple colored anthocyanins, found in both skin and flesh. Here, we present the first bilberry genome assembly, comprising 12 pseudochromosomes assembled using Oxford Nanopore (ONT) and Hi-C Technologies. The pseudochromosomes represent 96.6% complete BUSCO genes with an assessed LAI score of 16.3, showing a high conservation of synteny against the blueberry genome. Kmer analysis showed an unusual third peak, indicating the sequenced samples may have been from two individuals. The alternate alleles were purged so that the final assembly represents only one haplotype. A total of 36,404 genes were annotated after nearly 48% of the assembly was masked to remove repeats. To illustrate the genome quality, we describe the complex MYBA locus, and identify the key regulating MYB genes that determine anthocyanin production. The new bilberry genome builds on the genomic resources and knowledge of Vaccinium species, to help understand the genetics underpinning some of the quality attributes that breeding programs aspire to improve. The high conservation of synteny between bilberry and blueberry genomes means that comparative genome mapping can be applied to transfer knowledge about marker-trait association between these two species, as the loci involved in key characters are orthologous.     

Hydrocortisone increases the rate of differentiation of cultured human osteoblasts

Reduced bone formation is the main finding in glucocorticoid-induced osteoporosis. The aim of this study was to determine whether differentiation of cultured human osteoblasts is inhibited by high concentrations of hydrocortisone. We measured the levels of mRNAs for three markers of cellular differentiation, type 1 collagen (COL1), alkaline phosphatase (ALP), and osteocalcin (OC), in four lines of human osteoblasts from female donors cultured with doses of hydrocortisone from 0 microM to 4 microM. The change in ALP/COL1 mRNA ratio over a given time was used to determine the average rate of differentiation of the cells in a culture. Although basal expression profiles and their changes with time were different for the different cell lines, all cell lines showed a dose-dependent rise in the rate of increase of ALP mRNA relative to COL1 mRNA. However, increase in OC mRNA with time, seen here only in young donor hOBs, was significantly inhibited by 4 microM hydrocortisone, indicating that hydrocortisone can inhibit OC expression while promoting cellular differentiation. The data suggest that increasing concentrations of glucocorticoid, including concentrations similar to plasma levels in patients receiving oral glucocorticoid therapy, increase the rate of cellular differentiation.     

Western sandpipers have altered migration tactics as peregrine falcon populations have recovered

The presence of top predators can affect prey behaviour, morphology and life history, and thereby can produce indirect population consequences greater and further reaching than direct depredation would have alone. Raptor species in the Americas are recovering since restrictions on the use of dichlorodiphenyltrichloroethane (DDT) and the implementation of conservation measures, in effect constituting a hemisphere-wide predator-reintroduction experiment, and profound effects on populations of their prey are to be expected. Here, we document changes in the behaviour of western sandpipers (Calidris mauri) at migratory stopover sites over two decades. Since 1985, migratory body mass and stopover durations of western sandpipers have fallen steadily at some stopovers in the Strait of Georgia, British Columbia. Comparisons between years, sites and seasons strongly implicate increasing danger from the recovery of peregrine falcons (Falco peregrinus) as a causal factor. A decade-long ongoing steep decline in sandpiper numbers censused on our study site is explained entirely by the shortening stopover duration, rather than fewer individuals using the site. Such behavioural changes are probably general among migratory shorebird species, and may be contributing to the widespread census declines reported in North America.     

An in vitro model to evaluate cell adhesion to metals used in implantation shows significant differences between palladium and gold or platinum

Adhesion of tissue cells to metallic implants is a major factor that is important for proper tissue integration. Adhesion of Swiss mouse 3T3 fibroblasts to gold, platinum and palladium surfaces was investigated. Immunofluorescence staining for the integrin subunits alphav and beta1 and the focal contact protein vinculin revealed that cells growing on gold and platinum expressed many focal contacts. In contrast, cells on palladium surfaces had reduced numbers of focal contacts shown by vinculin staining and failed to demonstrate expression of alphav and beta1 in focal contacts. Spread cell area was also significantly reduced on palladium than on other surfaces suggesting that cells on palladium were more weakly attached. This may be due to either a different molecular composition of focal contacts in cells grown on palladium surfaces or unusual microstructural properties of the palladium surface. This model is useful to evaluate adhesion of cells to different metal surfaces.     

Heat shock proteins of chicken lens

The presence of heat shock proteins HSP-40, HSP-70, and HSc-70 in adult and embryonic chicken lenses were determined. The epithelium, cortex, and nucleus of adult chicken lens were separated and tested for the presence of heat shock proteins (hsps) by western blot, using specific antibodies for HSP-40, HSP-70, and HSc-70. Water soluble (WSF) and water insoluble fractions (WIF) of embryonic chicken lenses were isolated and tested for the presence of HSP-40, HSP-70, and HSc-70 by immunoblot. Embryonic chicken lens sections were also analyzed for the presence of heat shock proteins by immunofluorescence technique. Data obtained from these experiments revealed that HSP-40, HSP-70, and HSc-70 are present in all areas of both adult and embryonic chicken lens. Presence of hsps protein in the deep cortex and nucleus is intriguing as no detectable metabolic activities are reported in this area. However it can be proposed that hsps HSP-40, HSP-70, and HSc-70 can interact with protein of these areas and protect them from stress induced denaturation.