76 research outputs found
A comparison between the β-globin gene clusters of domestic sheep (Ovis aries) and Sardinian mouflon (Ovis gmelini musimon)
International audienc
Proline Enantiomers Discrimination by (L)-Prolinated Porphyrin Derivative Langmuir–Schaefer Films: Proof of Concept for Chiral Sensing Applications
A porphyrin derivative functionalized with the L-enantiomer of proline amino acid was characterized at the air–pure water interface of the Langmuir trough. The porphyrin derivative was dissolved in dichloromethane solution, spread at the air–subphase interface and investigated by acquiring the surface pressure vs. area per molecule Langmuir curves. It is worth observing that the behavior of the molecules of the porphyrin derivative floating film was substantially influenced by the presence of L-proline amino acid dissolved in the subphase (10−5 M); on the contrary, the physical chemical features of the floating molecules were only slightly influenced by the D-proline dissolved in the subphase. Such an interesting chirality-driven selection was preserved when the floating film was transferred onto solid supports by means of the Langmuir–Schaefer method, but it did not emerge when a spin-coating technique was used for the layering of the tetrapyrrolic derivatives. The obtained results represent proof of concept for the realization of active molecular layers for chiral discrimination: porphyrin derivatives, due to their intriguing spectroscopic and supramolecular properties, can be functionalized with the chiral molecule that should be detected. Moreover, the results emphasize the crucial role of the deposition technique on the features of the sensing layers
Proline enantiomers discrimination by (L)-prolinated porphyrin derivative Langmuir-Schaefer films: proof of concept for chiral sensing applications
A porphyrin derivative functionalized with the L-enantiomer of proline amino acid was characterized at the air-pure water interface of the Langmuir trough. The porphyrin derivative was dissolved in dichloromethane solution, spread at the air-subphase interface and investigated by acquiring the surface pressure vs. area per molecule Langmuir curves. It is worth observing that the behavior of the molecules of the porphyrin derivative floating film was substantially influenced by the presence of L-proline amino acid dissolved in the subphase (10(-5) M); on the contrary, the physical chemical features of the floating molecules were only slightly influenced by the D-proline dissolved in the subphase. Such an interesting chirality-driven selection was preserved when the floating film was transferred onto solid supports by means of the Langmuir-Schaefer method, but it did not emerge when a spin-coating technique was used for the layering of the tetrapyrrolic derivatives. The obtained results represent proof of concept for the realization of active molecular layers for chiral discrimination: porphyrin derivatives, due to their intriguing spectroscopic and supramolecular properties, can be functionalized with the chiral molecule that should be detected. Moreover, the results emphasize the crucial role of the deposition technique on the features of the sensing layers
Genetic characterization and implications for conservation of the last autochthonous Mouflon population in Europe
Population genetic studies provide accurate information on population structure, connectivity, and hybridization. These are key elements to identify units for conservation and define wildlife management strategies aimed to maintain and restore biodiversity. The Mediterranean island of Sardinia hosts one of the last autochthonous mouflon populations, descending from the wild Neolithic ancestor. The first mouflon arrived in Sardinia ~ 7000 years ago and thrived across the island until the twentieth century, when anthropogenic factors led to population fragmentation. We analysed the three main allopatric Sardinian mouflon sub-populations, namely: the native sub-populations of Montes Forest and Mount Tonneri, and the reintroduced sub-population of Mount Lerno. We investigated the spatial genetic structure of the Sardinian mouflon based on the parallel analysis of 14 highly polymorphic microsatellite loci and mitochondrial D-loop sequences. The Montes Forest sub-population was found to harbour the ancestral haplotype in the phylogeny of European mouflon. We detected high levels of relatedness in all the sub-populations and a mitochondrial signature of hybridization between the Mount Lerno sub-population and domestic sheep. Our findings provide useful insights to protect such an invaluable genetic heritage from the risk of genetic depletion by promoting controlled inter-population exchange and drawing informed repopulation plans sourcing from genetically pure mouflon stocks
Spectroscopic, Morphological and Mechanistic Investigation of the Solvent.Promoted Aggregation of Porphyrins Modified in meso-positions by Glucosylated steroids
Solvent-driven aggregation
of a series of porphyrin derivatives was
studied by UV/Vis and circular dichroism
spectroscopy. The porphyrins are
characterised by the presence in the
meso positions of steroidal moieties
further conjugated with glucosyl
groups. The presence of these groups
makes the investigated macrocycles
amphiphilic and soluble in aqueous solvent,
namely, dimethyl acetamide/
water. Aggregation of the macrocycles
is triggered by a change in bulk solvent
composition leading to formation of
large architectures that express supramolecular
chirality, steered by the presence
of the stereogenic centres on the
periphery of the macrocycles. The aggregation
behaviour and chiroptical
features of the aggregates are strongly
dependent on the number of moieties
decorating the periphery of the porphyrin
framework. In particular, experimental
evidence indicates that the
structure of the steroid linker dictates
the overall chirality of the supramolecular
architectures. Moreover, the porphyrin
concentration strongly affects
the aggregation mechanism and the
CD intensities of the spectra. Notably,
AFM investigations reveal strong differences
in aggregate morphology that
are dependent on the nature of the appended
functional groups, and closely
in line with the changes in aggregation
mechanism. The suprastructures
formed at lower concentration show a
network of long fibrous structures
spanning over tens of micrometres,
whereas the aggregates formed at
higher concentration have smaller rodshaped
structures that can be recognised
as the result of coalescence of
smaller globular structures. The fully
steroid substituted derivative forms
globular structures over the whole concentration
range explored. Finally, a rationale
for the aggregation phenomena
was given by semiempirical calculations
at the PM6 level
Selection of young ewe lambs according to their antral follicular count: response to exogenous hormonal stimulation and fertility at first breeding season
Anti-Mullerian Hormone (AMH), Antral Follicular Count (AFC) and the response to exogenous hormonal stimulation have been used, in adults, as suitable markers to determine the ovarian reserve (1-4), to predict oocyte quality (5,6) and a wide variety of fertility indices (6-9). This investigation aims to evaluate if animals selected according to their High or Low AFC at an early prepubertal age show different responses, in the number of follicles and AMH plasma levels, to exogenous hormonal stimulation; to verify whether differences are maintained over time until puberty; and to observe possible variations on fertility at first breeding season
Haplotype Affinities Resolve a Major Component of Goat (Capra hircus) MtDNA D-Loop Diversity and Reveal Specific Features of the Sardinian Stock
Goat mtDNA haplogroup A is a poorly resolved lineage absorbing most of the overall diversity and is found in locations as distant as Eastern Asia and Southern Africa. Its phylogenetic dissection would cast light on an important portion of the spread of goat breeding. The aims of this work were 1) to provide an operational definition of meaningful mtDNA units within haplogroup A, 2) to investigate the mechanisms underlying the maintenance of diversity by considering the modes of selection operated by breeders and 3) to identify the peculiarities of Sardinian mtDNA types. We sequenced the mtDNA D-loop in a large sample of animals (1,591) which represents a non-trivial quota of the entire goat population of Sardinia. We found that Sardinia mirrors a large quota of mtDNA diversity of Western Eurasia in the number of variable sites, their mutational pattern and allele frequency. By using Bayesian analysis, a distance-based tree and a network analysis, we recognized demographically coherent groups of sequences identified by particular subsets of the variable positions. The results showed that this assignment system could be reproduced in other studies, capturing the greatest part of haplotype diversity
Affinit\ue0 per l'ossigeno del sangue di muflone
Hemoglobin phenotypes of European mouflon and sheep were analyzed by isoelectric focusing; the results show that the sheep HbA migrated faster than that of other animals, while the mouflon HbA was more anodic than the sheep HbB. The oxygen dissociation curve of blood from mouflon is similar to that of sheep with HbA. The authors suggest that the mouflon should not be considered a direct ancestor of the Sardinian breed of sheep
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