716 research outputs found
Identification of new polymorphic regions and differentiation of cultivated olives (Olea europaea L.) through plastome sequence comparison
<p>Abstract</p> <p>Background</p> <p>The cultivated olive (<it>Olea europaea </it>L.) is the most agriculturally important species of the Oleaceae family. Although many studies have been performed on plastid polymorphisms to evaluate taxonomy, phylogeny and phylogeography of <it>Olea </it>subspecies, only few polymorphic regions discriminating among the agronomically and economically important olive cultivars have been identified. The objective of this study was to sequence the entire plastome of olive and analyze many potential polymorphic regions to develop new inter-cultivar genetic markers.</p> <p>Results</p> <p>The complete plastid genome of the olive cultivar Frantoio was determined by direct sequence analysis using universal and novel PCR primers designed to amplify all overlapping regions. The chloroplast genome of the olive has an organisation and gene order that is conserved among numerous Angiosperm species and do not contain any of the inversions, gene duplications, insertions, inverted repeat expansions and gene/intron losses that have been found in the chloroplast genomes of the genera <it>Jasminum </it>and <it>Menodora</it>, from the same family as <it>Olea</it>.</p> <p>The annotated sequence was used to evaluate the content of coding genes, the extent, and distribution of repeated and long dispersed sequences and the nucleotide composition pattern. These analyses provided essential information for structural, functional and comparative genomic studies in olive plastids. Furthermore, the alignment of the olive plastome sequence to those of other varieties and species identified 30 new organellar polymorphisms within the cultivated olive.</p> <p>Conclusions</p> <p>In addition to identifying mutations that may play a functional role in modifying the metabolism and adaptation of olive cultivars, the new chloroplast markers represent a valuable tool to assess the level of olive intercultivar plastome variation for use in population genetic analysis, phylogenesis, cultivar characterisation and DNA food tracking.</p
Human Papilloma Virus prevalence and type-specific relative contribution in invasive cervical cancer specimens from Italy
Background: Cervical cancer represents an important global public health problem. It is the 2(nd) most common cancer among women worldwide. Human Papillomavirus (HPV) infection is now well-established as a necessary cause of invasive cervical cancer (ICC) development. Only a few studies on HPV prevalence and type-specific distribution in ICC have been conducted in Italy. Aim: To describe the prevalence of HPV and the HPV type-specific distribution in ICC cases identified in Rome, Italy. Methods: 140 paraffin embedded tissue blocks of primary ICC diagnosed between 2001 and 2006 were identified at the Regina Elena Cancer Institute in Rome (Italy). HPV was detected through amplification of HPV DNA using SPF-10 HPV broad-spectrum primers followed by DEIA and then genotyping by LiPA(25) (version 1). Results: 134 cases were considered suitable for HPV DNA detection after histological evaluation; and overall, 90.3% (121/134) HPV prevalence was detected. 111 cases had a single HPV type, 4 cases had an uncharacterized type (HPVX) and 6 cases had multiple HPV infections. The five most common single HPV types among positive cases were: HPV16 (71/121; 58.7%), HPV18 (12/121; 9.9%), HPV31, HPV45 and HPV58 (5/121; 4.1% each). 2 (1.5%) of the single infections and 2 (1.5%) of the multiple infections contained low risk types. Statistically significant differences in the relative contribution of HPV18 were found when comparing squamous cell carcinomas with adenocarcinomas. Conclusions: HPV16 and HPV18 accounted for almost 70% of all the HPV positive ICC cases. The study provides baseline information for further evaluation on the impact of recently introduced HPV vaccines in Italy
The histone deacetylase inhibitor valproic acid attenuates phospholipase Cγ2 and IgE-mediated mast cell activation.
Mast cell activation through the high-affinity IgE receptor (FcεRI) plays a central role in allergic reactions. FcεRI-mediated activation triggers multiple signaling pathways leading to degranulation and synthesis of different inflammatory mediators. IgE-mediated mast cell activation can be modulated by different molecules, including several drugs. Herein, we investigated the immunomodulatory activity of the histone deacetylase inhibitor valproic acid (VPA) on IgE-mediated mast cell activation. To this end, bone marrow-derived mast cells (BMMC) were sensitized with IgE and treated with VPA followed by FcεRI cross-linking. The results indicated that VPA reduced mast cell IgE-dependent degranulation and cytokine release. VPA also induced a significant reduction in the cell surface expression of FcεRI and CD117, but not other mast cell surface molecules. Interestingly, VPA treatment inhibited the phosphorylation of PLCγ2, a key signaling molecule involved in IgE-mediated degranulation and cytokine secretion. However, VPA did not affect the phosphorylation of other key components of the FcεRI signaling pathway, such as Syk, Akt, ERK1/2, or p38. Altogether, our data demonstrate that VPA affects PLCγ2 phosphorylation, which in turn decreases IgE-mediated mast cell activation. These results suggest that VPA might be a key modulator of allergic reactions and might be a promising therapeutic candidate
Estimating the long-term impact of a prophylactic human papillomavirus 16/18 vaccine on the burden of cervical cancer in the UK
To predict the public health impact on cervical disease by introducing human papillomavirus (HPV) vaccination in the United Kingdom, we developed a mathematical model that can be used to reflect the impact of vaccination in different countries with existing screening programmes. Its use is discussed in the context of the United Kingdom. The model was calibrated with published data. The impact of vaccination on cervical cancer and deaths, precancerous lesions and screening outcomes were estimated for a vaccinated cohort of 12-year-old girls, among which it is estimated that there would be a reduction of 66% in the prevalence of high-grade precancerous lesions and a 76% reduction in cervical cancer deaths. Estimates for various other measures of the population effects of vaccination are also presented. We concluded that it is feasible to forecast the potential effects of HPV vaccination in the context of an existing national screening programme. Results suggest a sizable reduction in the incidence of cervical cancer and related deaths. Areas for future research include investigation of the beneficial effects of HPV vaccination on infection transmission and epidemic dynamics, as well as HPV-related neoplasms in other sites
Debris Disks: Probing Planet Formation
Debris disks are the dust disks found around ~20% of nearby main sequence
stars in far-IR surveys. They can be considered as descendants of
protoplanetary disks or components of planetary systems, providing valuable
information on circumstellar disk evolution and the outcome of planet
formation. The debris disk population can be explained by the steady
collisional erosion of planetesimal belts; population models constrain where
(10-100au) and in what quantity (>1Mearth) planetesimals (>10km in size)
typically form in protoplanetary disks. Gas is now seen long into the debris
disk phase. Some of this is secondary implying planetesimals have a Solar
System comet-like composition, but some systems may retain primordial gas.
Ongoing planet formation processes are invoked for some debris disks, such as
the continued growth of dwarf planets in an unstirred disk, or the growth of
terrestrial planets through giant impacts. Planets imprint structure on debris
disks in many ways; images of gaps, clumps, warps, eccentricities and other
disk asymmetries, are readily explained by planets at >>5au. Hot dust in the
region planets are commonly found (<5au) is seen for a growing number of stars.
This dust usually originates in an outer belt (e.g., from exocomets), although
an asteroid belt or recent collision is sometimes inferred.Comment: Invited review, accepted for publication in the 'Handbook of
Exoplanets', eds. H.J. Deeg and J.A. Belmonte, Springer (2018
The cometary composition of a protoplanetary disk as revealed by complex cyanides
Observations of comets and asteroids show that the Solar Nebula that spawned
our planetary system was rich in water and organic molecules. Bombardment
brought these organics to the young Earth's surface, seeding its early
chemistry. Unlike asteroids, comets preserve a nearly pristine record of the
Solar Nebula composition. The presence of cyanides in comets, including 0.01%
of methyl cyanide (CH3CN) with respect to water, is of special interest because
of the importance of C-N bonds for abiotic amino acid synthesis. Comet-like
compositions of simple and complex volatiles are found in protostars, and can
be readily explained by a combination of gas-phase chemistry to form e.g. HCN
and an active ice-phase chemistry on grain surfaces that advances
complexity[3]. Simple volatiles, including water and HCN, have been detected
previously in Solar Nebula analogues - protoplanetary disks around young stars
- indicating that they survive disk formation or are reformed in situ. It has
been hitherto unclear whether the same holds for more complex organic molecules
outside of the Solar Nebula, since recent observations show a dramatic change
in the chemistry at the boundary between nascent envelopes and young disks due
to accretion shocks[8]. Here we report the detection of CH3CN (and HCN and
HC3N) in the protoplanetary disk around the young star MWC 480. We find
abundance ratios of these N-bearing organics in the gas-phase similar to
comets, which suggests an even higher relative abundance of complex cyanides in
the disk ice. This implies that complex organics accompany simpler volatiles in
protoplanetary disks, and that the rich organic chemistry of the Solar Nebula
was not unique.Comment: Definitive version of the manuscript is published in Nature, 520,
7546, 198, 2015. This is the author's versio
High sample throughput genotyping for estimating C-lineage introgression in the dark honeybee: an accurate and cost-effective SNP-based tool
The natural distribution of the honeybee (Apis mellifera L.) has been changed by humans in recent
decades to such an extent that the formerly widest-spread European subspecies, Apis mellifera
mellifera, is threatened by extinction through introgression from highly divergent commercial strains
in large tracts of its range. Conservation efforts for A. m. mellifera are underway in multiple European
countries requiring reliable and cost-efficient molecular tools to identify purebred colonies. Here, we
developed four ancestry-informative SNP assays for high sample throughput genotyping using the
iPLEX Mass Array system. Our customized assays were tested on DNA from individual and pooled,
haploid and diploid honeybee samples extracted from different tissues using a diverse range of
protocols. The assays had a high genotyping success rate and yielded accurate genotypes. Performance
assessed against whole-genome data showed that individual assays behaved well, although the
most accurate introgression estimates were obtained for the four assays combined (117 SNPs).
The best compromise between accuracy and genotyping costs was achieved when combining two
assays (62 SNPs). We provide a ready-to-use cost-effective tool for accurate molecular identification
and estimation oinfo:eu-repo/semantics/publishedVersio
Yeasts associated with the production of distilled alcoholic beverages
Distilled alcoholic beverages are produced firstly by fermenting sugars emanating from cereal starches (in the case of whiskies), sucrose-rich plants (in the case of rums), fructooligosaccharide-rich plants (in the case of tequila) or from fruits (in the case of brandies). Traditionally, such fermentations were conducted in a spontaneous fashion, relying on indigenous microbiota, including wild yeasts. In modern practices, selected strains of Saccharomyces cerevisiae are employed to produce high levels of ethanol together with numerous secondary metabolites (eg. higher alcohols, esters, carbonyls etc.) which greatly influence the final flavour and aroma characteristics of spirits following distillation of the fermented wash. Therefore, distillers, like winemakers, must carefully choose their yeast strain which will be very important in providing the alcohol content and the sensory profiles of spirit beverages. This Chapter discusses yeast and fermentation aspects associated with the production of selected distilled spirits and highlights similarities and differences with the production of wine
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