442 research outputs found
Casein haplotype variability in Sicilian dairy goat breeds
In the Mediterranean region, goat milk production is an important economic activity. In the present study, 4 casein genes were genotyped in 5 Sicilian goat breeds to 1) identify casein haplotypes present in the Argentata dell'Etna, Girgentana, Messinese, Derivata di Siria, and Maltese goat breeds; and 2) describe the structure of the Sicilian goat breeds based on casein haplotypes and allele frequencies. In a sample of 540 dairy goats, 67 different haplotypes with frequency >or=0.01 and 27 with frequency >or=0.03 were observed. The most common CSN1S1-CSN2-CSN1S2-CSN3 haplotype for Derivata di Siria and Maltese was FCFB (0.17 and 0.22, respectively), whereas for Argentata dell'Etna, Girgentana and Messinese was ACAB (0.06, 0.23, and 0.10, respectively). According to the haplotype reconstruction, Argentata dell'Etna, Girgentana, and Messinese breeds presented the most favorable haplotype for cheese production, because the casein concentration in milk of these breeds might be greater than that in Derivata di Siria and Maltese breeds. Based on a cluster analysis, the breeds formed 2 main groups: Derivata di Siria, and Maltese in one group, and Argentata dell'Etna and Messinese in the other; the Girgentana breed was between these groups but closer to the latter
Swings between rotation and accretion power in a millisecond binary pulsar
It is thought that neutron stars in low-mass binary systems can accrete
matter and angular momentum from the companion star and be spun-up to
millisecond rotational periods. During the accretion stage, the system is
called a low-mass X-ray binary, and bright X-ray emission is observed. When the
rate of mass transfer decreases in the later evolutionary stages, these
binaries host a radio millisecond pulsar whose emission is powered by the
neutron star's rotating magnetic field. This evolutionary model is supported by
the detection of millisecond X-ray pulsations from several accreting neutron
stars and also by the evidence for a past accretion disc in a rotation-powered
millisecond pulsar. It has been proposed that a rotation-powered pulsar may
temporarily switch on during periods of low mass inflow in some such systems.
Only indirect evidence for this transition has hitherto been observed. Here we
report observations of accretion-powered, millisecond X-ray pulsations from a
neutron star previously seen as a rotation-powered radio pulsar. Within a few
days after a month-long X-ray outburst, radio pulses were again detected. This
not only shows the evolutionary link between accretion and rotation-powered
millisecond pulsars, but also that some systems can swing between the two
states on very short timescales.Comment: 43 pages, 9 figures, 4 table. Published by Nature on 26 Sep 2013.
Includes Supplementary information. Minor differences with published version
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The role of Runx1 in genetic models of breast cancer
Given the recent discovery of RUNX1 somatic mutations in biopsies of breast cancer patients, the overall purpose of the present thesis consists of using different in vivo and ex vivo experimental systems in the attempt to answer two main questions: firstly, if the Runx1 gene plays any causative role in the context of breast cancer; and secondly, if its putative function is symptomatic of a tumour suppressor gene and/or of a pro-oncogene.
By characterizing the effects of Runx1 deletion in two different breast cancer mouse models (i.e. the MMTV-PyMT and the Wnt/β-catenin-driven models of mammary tumourigenesis), this thesis provides the first in vivo evidence of a dualistic role played by the gene in the context of breast cancer. Runx1 would in fact appear to act as a tumour suppressor at early stages of the disease, whilst as a pro-oncogene at later stages of mammary tumourigenesis.
To fully comprehend the significance of these major findings, the introduction will first provide a brief description on the RUNX family of genes, as well as on the state-of-the-art knowledge of RUNX1’s role in both mammary gland and breast cancer biology. As such, particular attention will then be given not only to the ontogeny, endocrine regulation and composition of the murine mammary gland, yet also to the high degree of heterogeneity, the putative “cell-of-origin(s)” and the different experimental models commonly used to study breast cancer.
Through the aforementioned rationale, it is hoped that the introduction will serve as a platform which may hold the key for unveiling the controversial role played by RUNX1 in the context of breast cancer
Maedi Visna virus infection and TMEM154 genotypes in Valle del Belìce sheep breed
Maedi Visna (MV) is a viral infection in sheep caused by Lentivirus and characterised by a long incubation period, slow progression, weight loss and eventually death. TMEM154 was reported in the ovine as major candidate gene associated with host susceptibility/resistance. The aim of this study was to verify the prevalence of MV infection within Sicilian herds of Valle del Belìce breed using an ELISA serological test and to estimate the frequencies of the resistant/susceptible genotypes to the TMEM154 gene. Finally, we investigated the association between TMEM154 E/K genotype and MV infectious status. A total of 1,083 animals from different flocks were tested. The ELISA method showed 15.33% (n = 166) of infected individuals. Analyses of the sequences showed the presence of both K and E alleles with frequencies of 0.151 and 0.849, respectively. On the total individuals, only 23 carried KK genotype while 280 were heterozigous EK, and 780 homozygous EE. The locus was in Hardy-Weinberg equilibrium in the breed (p-value <0.05) and observed and expected heterozygosity values were 0.258 and 0.256, respectively. Moreover, a significant association (p-value < 0.001) between TMEM154 genotypes and seroprevalence status (positive vs. negative) was found. This study allowed us to know the prevalence of MV infection in Sicilian flocks of Valle del Belìce breed and could be helpful in establishing selection programs aimed at controlling and eradicating this virus
Predictability of anthropomorphic measurements in implant selection for breast reconstruction : a retrospective cohort study
BACKGROUND:
Preoperative implant planning for breast reconstruction is often at risk of being changed perioperatively. This study examined which factors are associated with a change of implant selection.
METHODS:
Women who had unilateral two-stage breast reconstruction between 2002 and 2007 were studied. Inclusion criteria were photographic evidence of preoperative skin markings indicating breast dimensions and a selected implant model. Multivariable logistic regression was used to identify variables associated with a changed selection.
RESULTS:
Among the 496 women studied, 308 preoperative implant choices (62.1%) were changed during surgery. A change in plan was significantly associated with symmetrization surgery involving contralateral reduction mammaplasty (OR = 1.92; 95% CI, 1.12 to 3.29) and contralateral mastopexy (OR = 2.26; 95% CI, 1.29 to 3.96), but not with BMI. The required implant width changed more than 0.5 cm in 70 cases (14.1%) while height changed more than 0.5 cm in 215 cases (43.2%). The likelihood of a change was high for large preoperative widths (OR = 9.66 for 15.5 cm) and small preoperative heights (OR = 2.97 for 10.5 cm). At a mean follow-up of 16.6 months, patient satisfaction was good or average in 92.1% of cases and 5.9% of implants had been replaced with another model, indicating that the perioperative implant selection was usually appropriate.
CONCLUSIONS:
This study documents the frequency with which implant choices, despite accurate preoperative planning, are changed perioperatively as a result of relatively small differences in anthropomorphic measurements. Perioperative recalculation of breast dimensions may have an advantage in terms of patient reoperation rates. Changes in width were less frequent than changes in height and projection. Contralateral surgery, large width, and small height were the most influential factors. Level of Evidence: Level IV, risk / prognostic study
High-density SNP markers elucidate the genetic divergence and population structure of Noticiana sheep breed in the Mediterranean context
Among livestock species, sheep have played an early major role in the Mediterranean area. Italy has a long history of sheep breeding and, despite a dramatic contraction in numbers, still raise several local populations that may represent a unique source of genetic diversity. The Noticiana is a breed of the south-eastern part of Sicily appreciated both for its dairy products and for its resistance to harsh environment. In this study, the high-density Illumina Ovine SNP600K BeadChip array was used for the first genome-wide characterization of 48 individuals of Noticiana sheep to investigate its diversity, the genome structure and the relationship within the context of worldwide and Italian breeds. Moreover, the runs of homozygosity (ROH) pattern and the pairwise FST-outliers were examined. Noticiana reported moderate levels of genetic diversity. The high percentage of short and medium length ROH segments (93% under 4 Mb) is indicative of a within breed relatedness dating back to ancient times, despite the absence of management for the mating plans and the reduced population size. In the worldwide context, the Southern Italian, Spanish and Albanian breeds overlapped in a macro cluster which also included the Noticiana sheep. The results highlighted ancestral genetic components of Noticiana shared with Comisana breed, and showed the clear separation from the other Italian sheep. This is likely the consequence of the combined effects of genetic drift, small population size and reproductive isolation. ROH islands and FST-outliers approaches in Noticiana identified genes and QTLs involved in milk and meat production, as well as related to the local adaptation, and therefore are consistent with the phenotypic traits of the studied breed. Although a wider sampling could be useful to deepen the genomic survey on Noticiana, these results represent a crucial starting point for the characterization of an important local genetic resource, with a view of supporting the local economy and preserving the biodiversity of the sheep species
Genome wide analyses reveal the population distinctiveness of the ‘Nera del Mela’ sheep
Italy has a long history of sheep breeding and counts several local populations that may represent a unique source of genetic diversity. Among these, Nera del Mela is a sheep genetic resource historically reared in Sicily but not officially recognised as a breed. In this study, we genotyped 36 individuals of Nera del Mela using the OvineSNP50K array, in order to estimate the genetic diversity and evaluate the population structure and relatedness with other Italian sheep breeds. Genetic diversity indices, and inbreeding estimated from runs of homozygosity (FROH) revealed a moderate level of variability. Runs of homozygosity islands mapped candidate genes involved in the adaptation to local environment and immune response. Population genetic analyses using different approaches highlighted the hypothesis that this sheep possesses a defined genetic structure, especially if compared with other recognised breeds, despite the influence of other populations such as the Sicilian breeds. Overall, our findings represent a starting point for the possible official acknowledgement of this population, for the creation of a conservation plan, and thus for preserving this genomic heritage.HIGHLIGHTS Nera de Mela sheep can be considered as a reservoir of genetic diversity. The results indicated a clear genetic differentiation from other populations and moderate level of genetic variability. Our findings represent a starting point for the creation of conservation plans
High-density single nucleotide polymorphism markers reveal the population structure of 2 local chicken genetic resources
Italy counts a large number of local chicken populations, some without a recognized genetic structure, such as Val Platani (VPL) and Cornuta (COS), which represent noteworthy local genetic resources. In this study, the genotype data of 34 COS and 42 VPL, obtained with the Affymetrix Axiom600KChicken Genotyping Array, were used with the aim to investigate the genetic diversity, the runs of homozygosity (ROH) pattern, as well as the population structure and relationship within the framework of other local Italian and commercial chickens. The genetic diversity indices, estimated using different approaches, displayed moderate levels of genetic diversity in both populations. The identified ROH hotspots harbored genes related to immune response and adaptation to local hot temperatures. The results on genetic relationship and population structure reported a clear clustering of the populations according to their geographic origin. The COS formed a nonoverlapping genomic cluster and clearly separated from the other populations, but showed evident proximity to the Siciliana breed (SIC). The VPL highlighted intermediate relationships between the COS-SIC group and the rest of the sample, but closer to the other Italian local chickens. Moreover, VPL showed a complex genomic structure, highlighting the presence of 2 subpopulations that match with the different source of the samples. The results obtained from the survey on genetic differentiation underline the hypothesis that Cornuta is a population with a defined genetic structure. The substructure that characterizes the Val Platani chicken is probably the consequence of the combined effects of genetic drift, small population size, reproductive isolation, and inbreeding. These findings contribute to the understanding of genetic diversity and population structure, and represent a starting point for designing programs to monitor and safeguard these local genetic resources, in order to define a possible official recognition program as breeds
Cat-Owner Relationship and Cat Behaviour : Effects of the COVID-19 Confinement and Implications for Feline Management
The aim of this study was to explore the effects of the Italian COVID-19 lockdown on the cat-owner relationship and on cat behaviour. In order to do so, we used a questionnaire to obtain information on the owner and cat's demographics, living environment, cat behaviour, and possible changes in some aspects of the cat-owner relationship. The questionnaire was distributed online when the lockdown was still ongoing and was completed by 548 cat owners, mainly women. Our findings suggest that the greater amount of time that owners spent at home with their cats, as a consequence of the social restrictions, had a positive effect on the owner's perception of their relationship with their cat (e.g., higher frequency of interaction, greater emotional closeness, reduced perceived costs of caring for the cat). Similarly, the lockdown seemed to have improved the welfare of many cats, as suggested by the positive changes in many of their behaviours, even for those cats with pre-existing behavioural problems. Overall, our findings suggest that the lockdown provided many cats with a more thriving physical and social environment. They also highlight the need to reconsider some cat management practices commonly implemented in non-exceptional circumstances. The restrictive measures implemented to stem the spread of COVID-19 abruptly changed the lives of many cats and their owners. This study explored whether the lockdown in Italy affected the cat-owner relationship, as well as cat behaviour and welfare. A survey that included questions on owner and cat's demographics, living environment, cat behaviour and a modified version of the Cat/Dog Relationship Scale (C/DORS) was distributed online during the lockdown and was completed by 548 cat owners, mainly women (81.6%). With regard to the C/DORS subscales, both emotional closeness and cat-owner interactions increased during confinement, as opposed to a reduction in perceived costs. The effect of the type of job, family role and owner's age on the C/DORS scores suggests that the relationship improved for those owners that, due to the lockdown, increased the time spent with their cats. For 58.8% of respondents, their cat's general behaviour did not change, but when changes occurred, they were mostly positive (20.4%). Attention-seeking and demanding behaviours were the most increased during lockdown (25.7%). Cats with pre-existing problematic behaviours tended to either remain stable or improve during confinement. The overall positive effects of lockdown-related environmental changes on a cat's behaviour suggest that some aspects of commonly implemented cat management practices should be revised to improve cat welfare in normal circumstances
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