The Montagu’s harrier (
Circus pygargus
) is a semi-colonial raptor species widely but patchily distributed across the Palearctic region with recorded cases of philopatry and presence of extra-pair ...copulation. In order to assess Montagu’s harrier spatial genetic structure and contemporary gene flow, we developed 16 new microsatellite markers using 454 pyrosequencing. Genotypes of 117 chicks sampled in a 200 × 300 km farmland area in Central Western France were analyzed to characterize genetic polymorphism at each locus and regional and fine-scale genetic structure. Fourteen markers were found polymorphic, with a number of alleles ranging from 3 to 11. The expected and observed heterozygosities ranged from 0.36 to 0.856 and from 0.35 to 0.868, respectively. A single genetic unit was found at the regional scale with higher genetic similarity observed at a small spatial scale (up to 10 km). Our results are consistent with overall large-scale juvenile and adult dispersal together with small-scale male philopatry. Cross-species amplification of this set of microsatellites makers has been successful in two closely related harrier species: the marsh harrier (
Circus aeruginosus
) and the Hen harrier (
Circus cyaneus
) for which 14 and 12 markers were polymorphic, respectively. These new microsatellite markers could be used to study the population genetic structure, contemporary gene flow and parentage analyses in these three species and to conduct microsatellite-based demographic inferences on the Montagu’s harrier.
Seabird life-history traits such as long generation time, low annual fecundity and delayed sexual maturation make them more prone to population loss and consequently to extinction; petrels are indeed ...amongst the most threatened birds. Based on coalescence and multiloci inference this study examines the extent of genetic differentiation of a vulnerable New Caledonia (
caledonica
) and Australia (
leucoptera
) subspecies of
Pterodroma leucoptera
(Gould’s Petrel), and whether the genetic relationship between them results from the influence of past events like variation in sea level, or is dominated by contemporary gene flow. Sequences of two mitochondrial genes and five nuclear introns were obtained from 86 individuals from both populations. Haplotype networks were used to infer relationships between the haplotypes of both populations. The demographic history of the
P. leucoptera
complex was studied using neutrality tests and Extended Bayesian Skyline Plots. A weak population differentiation was revealed. The Extended Bayesian Skyline plot suggested a population expansion approximately 80,000 years before present (bp) for
caledonica
and 30,000 years bp for
leucoptera
. The split was dated to 30,000 years bp by means of multilocus inference through *BEAST. Despite genetic similarity of the two taxa, we advocate to consider them as independent units for conservation management, given their strong ecological distinctiveness (foraging distribution, winter distribution, breeding phenology and breeding distribution).
Differentiation of naïve B cells into plasma cells or memory cells occurs in the germinal centers (GCs) of lymph follicles or alternatively via a GC- and T-cell-independent pathway. It is currently ...assumed that B-cell lymphomas correlate to normal B-cell differentiation stages, but the precise correlation of several B-cell lymphomas to these two pathways remains controversial. In the present report, we describe the junctional adhesion molecule C (JAM-C), currently identified at the cell-cell border of endothelial cells, as a new B-cell marker with a tightly regulated expression during B-cell differentiation. Expression of JAM-C in tonsils allows distinction between two CD27+ B-cell subpopulations: JAM-C- GC B cells and JAM-C+ non-germinal B cells. The expression of JAM-C in different B-cell lymphomas reveals a disease-specific pattern and allows a clear distinction between JAM-C- lymphoproliferative syndromes (chronic lymphocytic leukemia, mantle cell lymphoma and follicular lymphoma) and JAM-C+ ones (hairy cell leukemia, marginal zone B-cell lymphoma). Therefore, we propose JAM-C as a new identification tool in B-cell lymphoma diagnosis.
Molluscs have undergone many transitions between separate sexes and hermaphroditism, which is of interest for studying the evolution of sex determination and differentiation. Here we combined ...multi-locus genotypes obtained from RAD sequencing with anatomical observations of the gonads for three deep-sea hydrothermal vent gastropods of the genus Alviniconcha living in the southwest Pacific. We found that all three species (A. boucheti, A. strummeri, and A. kojimai) share the same male-heterogametic XY sex determination system, but that the gonads of XX A. kojimai individuals are invaded by a variable proportion of male reproductive tissue. The identification of Y-specific RAD loci (found only in A. boucheti) and the phylogenetic analysis of three sex-linked loci shared by all species suggested that X-Y recombination has evolved differently within each species. This situation of three species showing variation in gonadal development around a common sex determination system provides new insights into the reproductive mode of poorly known deep-sea species and opens up an opportunity to study the evolution of recombination suppression on sex chromosomes and its association with mixed or transitory sexual systems.
The seed or ‘bean’ of the coffee plant is an important crop, grown commercially across the world. Two species are commonly cultivated:
Coffea arabica and
Coffea canephora variant
robusta. Analytical ...techniques for species identification, in particular of coffee products such as ground or ‘instant’ coffees, are of great importance. In this paper, mid-infrared spectroscopy is proposed as a rapid alternative to existing authentication methods, which are often time-consuming or difficult to implement successfully. A Fourier-transform infrared spectrometer is used for this work, equipped with a diffuse reflectance accessory. Statistical procedures comprising principal components analysis and classical discriminant analysis are applied to spectra of ground roast
arabica and
robusta beans, and results presented which demonstrate that the species of such samples can readily be identified.
Reconstruction of the genitourinary tract, using engineered urological tissues, requires a mechanically stable biodegradable and biocompatible scaffold and cultured cells. Such engineered autologous ...tissue would have many clinical implications. In this study a highly porous biodegradable polyesterurethane-foam, DegraPol
® was evaluated with tissue engineered human primary bladder smooth muscle cells. The cell–polymer constructs were characterized by histology, scanning electron microscopy, immunohistochemistry and proliferation assays. Smooth muscle cells grown on DegraPol
® showed the same morphology as when grown on control polystyrene surface. Positive immunostaining with alpha smooth muscle actin indicated the preservation of the specific cell phenotype. Micrographs from scanning electron microscopy showed that the cells grew on the foam surface as well as inside the pores. In addition they grew as cell aggregates within the foam. The smooth muscle cells proliferated on the Degrapol
®; however, proliferation rate decreased due to apoptosis with time in culture. This study showed that Degrapol
® has the potential to be used as a scaffold.
PU.1, a transcription factor of the ETS family, plays a pivotal role in normal hematopoiesis, and particularly in myeloid differentiation. Altered PU.1 function is possibly implicated in ...leukemogenesis, as PU.1 gene mutations were identified in some patients with acute myeloid leukemia (AML) and as several oncogenic products (AML1-ETO, promyelocytic leukemia-retinoic acid receptor alpha, FMS-like receptor tyrosine kinase 3 internal tandem duplication) are associated with PU.1 downregulation. To demonstrate directly a role of PU.1 in the blocked differentiation of leukemic blasts, we transduced cells from myeloid cell lines and primary blasts from AML patients with a lentivector encoding PU.1. In NB4 cells we obtained increases in PU.1 mRNA and protein, comparable to increases obtained with all-trans retinoic acid-stimulation. Transduced cells showed increased myelomonocytic surface antigen expression, decreased proliferation rates and increased apoptosis. Similar results were obtained in primary AML blasts from 12 patients. These phenotypic changes are characteristic of restored blast differentiation. PU.1 should therefore constitute an interesting target for therapeutic intervention in AML.
In tissue engineering, degradable or non-degradable polymer matrices can act as cell-carrier-scaffolds. Cell adhesion and growth on these scaffolds can be promoted by immobilizing extracellular ...matrix proteins. Therefore, in this study, polymer poly(ethylene terephthalate) (PET) films were surface modified by graft polymerization of acrylic acid, to subsequently allow collagen (types I and III) immobilization and human smooth muscle cell expansion. The surfaces of PET were activated by plasma, followed by acrylic acid graft polymerization, resulting in covalently bound brushes, containing an average of either 0.22±0.1 or 5.93±0.87
μg/cm
2 of poly(acrylic acid) (PAA). Subsequent electrostatic adsorption of collagen gave a surface concentration of 4.96 and 17.2
μg/cm
2, respectively, as determined using radiolabelled
125I collagen. Both PET films grafted with 0.22
μg/cm
2 of PAA with or without adsorbed collagen were apt for smooth muscle cell adhesion and proliferation. However, films grafted with 5.93
μg/cm
2 were not. PAA-grafted PET films, onto which serum proteins of the culture medium adsorbed spontaneously, proved to be better matrices than films on which collagen has been immobilized. It, therefore, can be speculated that other serum proteins are more important than collagen for the human smooth muscle cell adhesion and growth on surface-modified polymer matrices.
Several congenital and acquired diseases of the human genito-urinary tract may need, due to lack or destruction of functional tissues, mechanically stable biomaterials as cell carriers for the ...engineering of these tissues.
When using collagen scaffolds, both their capacity to induce tissue regeneration and their biocompatibility are advantageous characteristics to render them apt for tissue engineering. The attachment of extracellular matrix or serum proteins to their surfaces does further improve these characteristics, mimicking a close to natural cell environment. In this study, equine collagen scaffolds (TissueFleece
®) were modified by coating fetal bovine serum proteins, before human bladder smooth muscle cells were seeded. Cell growth was evaluated by WST-1 proliferation assay and improved when using modified collagen scaffolds. However, cell penetration assessed by histology showed similar results on modified and native scaffolds. These cell-scaffold constructs were further implanted in the dorsal subcutaneous space of athymic mice. In vivo studies showed the presence of the fluorescent-labeled transplanted smooth muscle cells until day 3 and thereafter angiogenesis was induced and infiltration of mouse fibroblasts and polymorphonuclear cells were observed. The latter had completely disappeared after 3 weeks.
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