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1.
Evidence for a quadruplex structure in the polymorphic hs1.2 enhancer of the immunoglobulin heavy chain 3’ regulatory regions and its conservation in mammals 下载免费PDF全文
2.
Mauro Musto Daniele Cardinale Pietro Lucia Daniela Faraone 《Journal of applied animal welfare science : JAAWS》2016,19(3):217-233
This study evaluated whether showing a video of the different ways of raising goats for milk affected consumer acceptability. Four combinations, 2 Videos (intensive [INT] and semiextensive [SEM] system) × 2 Milk Types (semiskimmed [S] and whole [W] milk), were evaluated by 70 habitual consumers of goat milk, who scored their liking and purchase intention during blind (B), expected (E), and informed (I) acceptability sessions. In the B session, consumers tasted both milk types without information. S samples were preferred over W samples. In the E session, SEM video created high expectations in terms of milk liking and purchase intent, whereas the opposite happened when showing INT video. In the I session, consumers showed a clear preference for combinations created using SEM video, regardless of milk type. W-SEM and S-INT were worse (negative disconfirmation) and better (positive disconfirmation) than expected, respectively. A complete assimilation toward expectations occurred only for S-INT. INT video adversely affected the acceptability of S samples. Concerning purchase intent, W-SEM and S-SEM were worse than expected, but the assimilation was complete only for S-SEM: SEM video increased purchase intent for S samples. 相似文献
3.
Giorgia Manzo Mariano A. Scorciapino Parvesh Wadhwani Jochen Bürck Nicola Pietro Montaldo Manuela Pintus Roberta Sanna Mariano Casu Andrea Giuliani Giovanna Pirri Vincenzo Luca Anne S. Ulrich Andrea C. Rinaldi 《PloS one》2015,10(1)
SB056 is a novel semi-synthetic antimicrobial peptide with a dimeric dendrimer scaffold. Active against both Gram-negative and -positive bacteria, its mechanism has been attributed to a disruption of bacterial membranes. The branched peptide was shown to assume a β-stranded conformation in a lipidic environment. Here, we report on a rational modification of the original, empirically derived linear peptide sequence [WKKIRVRLSA-NH2, SB056-lin]. We interchanged the first two residues [KWKIRVRLSA-NH2, β-SB056-lin] to enhance the amphipathic profile, in the hope that a more regular β-strand would lead to a better antimicrobial performance. MIC values confirmed that an enhanced amphiphilic profile indeed significantly increases activity against both Gram-positive and -negative strains. The membrane binding affinity of both peptides, measured by tryptophan fluorescence, increased with an increasing ratio of negatively charged/zwitterionic lipids. Remarkably, β-SB056-lin showed considerable binding even to purely zwitterionic membranes, unlike the original sequence, indicating that besides electrostatic attraction also the amphipathicity of the peptide structure plays a fundamental role in binding, by stabilizing the bound state. Synchrotron radiation circular dichroism and solid-state 19F-NMR were used to characterize and compare the conformation and mobility of the membrane bound peptides. Both SB056-lin and β-SB056-lin adopt a β-stranded conformation upon binding POPC vesicles, but the former maintains an intrinsic structural disorder that also affects its aggregation tendency. Upon introducing some anionic POPG into the POPC matrix, the sequence-optimized β-SB056-lin forms well-ordered β-strands once electro-neutrality is approached, and it aggregates into more extended β-sheets as the concentration of anionic lipids in the bilayer is raised. The enhanced antimicrobial activity of the analogue correlates with the formation of these extended β-sheets, which also leads to a dramatic alteration of membrane integrity as shown by 31P-NMR. These findings are generally relevant for the design and optimization of other membrane-active antimicrobial peptides that can fold into amphipathic β-strands. 相似文献
4.
João M. Pizauro Pietro Ciancaglini Francisco A. Leone 《Molecular and cellular biochemistry》1995,145(2):121-129
S-2-(3 aminopropylamino) ethylphosphorothioic acid (WR-2721) shown to surpass radical scavenging thiols in their radioprotective efficacy in cancer-type diseases has been tested for its protective potential in the reperfused heart. We investigated the radical scavenger properties of the compound in a radical generating systemin vitro as well as in isolated rat hearts subjected to 30 min ischaemia and 30 min reperfusion with the electron-paramagnetic resonance spin trap technique. The action on high-energy phosphates is observed by means of phosphorus-31 nuclear magnetic resonance (NMR) spectroscopy while its influence on left ventricular systolic segmental length change (SSLC) during 60 min reperfusion following 60 min regional ischaemia was assessed with a fibreoptic system in anaesthetized open-chest rats. WR-2721 (0.1 mM) reduced the vascular concentration of radical adduct in isolated hearts by up to 78% (275±84% of pre-ischaemic baseline values vs 1260±413%, p<0.05) between 5 and 12.5 min reperfusion. This was accompanied by a reduction of the left ventricular end diastolic pressure to pre-ischaemic values at 30 min of reperfusion (9±6 mmHg vs 42±8 mmHg in the absence of WR-2721, p<0.02). An accelerated recovery of creatine phosphate levels (78±5% of pre-ischaemia values vs 41±5% within 60 min reperfusion; p<0.05) was observed under similar conditions with NMR-spectroscopy, although the post-ischaemic tissue content of adenosine triphosphate was not affected. The administration of WR-2721 (0.5 mmol/kg body weight) ledin situ to an accelerated restoration of contractile activity in the post-ligated left ventricular area reflected by the post-ischaemic recovery of SSLC (64±10% of pre-ischaemic values compared with 27±6% in control animals 60 min following reperfusion; p<0.02). The present data confirm an effective reduction in the exposure of the reperfused heart to endogenously released free radicals by WR-2721, a partial preservation of high-energy phosphates and an improvement in post-ischaemic contractility and encourage further investigation of such favourable action in injured myocardium. 相似文献
5.
6.
Questions
What are the syntaxonomic and synchorological patterns of the xerothermic chasmophytic vegetation in the central part of the Mediterranean Basin? What are the diagnostic species of the high‐rank syntaxa of Asplenietalia glandulosi, Onosmetalia frutescentis and Centaureo dalmaticae‐Campanuletalia pyramidalis?Location
Mediterranean coastal and subcoastal areas of southern France, Italy, Malta, Slovenia, Croatia, Bosnia and Herzegovina, Montenegro, Albania and of mainland Greece.Methods
The data set of 1,261 published relevés was analysed using hierarchical clustering (Flexible Beta method), involving a series of data transformations. Indicator species analysis was used to select the best dendrogram solution and identify diagnostic taxa of the main clusters. The dendrogram was interpreted from a syntaxonomic point of view, using nomenclatural type relevés as a basis. The NMDS ordination was performed in order to visualize the floristic relationships among associations and high‐rank syntaxa. MRPP was used to test for differences among alliances.Results
The classification revealed four main clusters of relevés representing the chasmophytic vegetation of southern France, Sardinia and the northwestern part of Italy (Asplenienalia glandulosi/Asplenietalia glandulosi), the southwestern part of Italy and Malta (Tinguarrenalia siculae/Asplenietalia glandulosi), the Adriatic Basin area (Centaureo dalmaticae‐Campanuletalia pyramidalis) and the southern Balkans (Onosmetalia frutescentis). The NMDS ordination confirmed the overall pattern, while MRPP showed significant differences among the alliances of the above‐mentioned orders and suborders. The lists of diagnostic taxa of the high‐rank syntaxa were revised according to a supra‐national perspective.Conclusions
The new syntaxonomic scheme provides a comprehensive overview of the chasmophytic vegetation of the central part of the Mediterranean Basin. This scheme mostly matches the recently published EuroVegChecklist, but also exhibits important novelties concerning the syntaxonomic position of some alliances (Dianthion rupicolae, Centaureion pentadactyli, Arenarion bertolonii and Caro‐Aurinion), and the floristic and chorological relationships among high‐rank syntaxa, with new revised sets of diagnostic taxa. This revision might be useful for further small‐scale phytosociological studies.7.
Mario Di Staso Giovanni Luca Gravina Luigi Zugaro Pierluigi Bonfili Lorenzo Gregori Pietro Franzese Francesco Marampon Francesca Vittorini Roberto Moro Vincenzo Tombolini Ernesto Di Cesare Carlo Masciocchi 《PloS one》2015,10(6)
Purpose
aim of this study was to identify outcomes in pain relief and quality of life in patients with a solitary painful osseous metastasis treated by radiotherapy, cryoablation or the combination using a propensity score matching study design.Materials and Methods
175 patients with painful bone metastases were included in the study. Twenty-five of them underwent a radiation course (20 Gy in five daily fractions) 15 days after the cryoablation. These subjects were retrospectively matched by propensity analysis with a group of subjects treated by radiotherapy (125 subjects) and with a group treated byCryoablation (25 subjects). The pain relief in terms of complete response, rate of subjects requiring analgesics after treatments and the changes in self-rated quality of life were measured. Informed consent was obtained from the subject and the study was approved by the local Ethical Committee.Results
An higher proportion of subjects treated by cryoablation (32%) or cryoablation followed by RT (72%;) experienced a complete response compared with patients treated by radiotherapy alone (11.2%). After Bonferroni correction strategy, the addition of radiotherapy to cryoablation significantly improved the rate of complete response compared with cryoablation alone (p = 0.011) and this paralleled with an improved self-rated quality of life. Seventeen subjects (13.6%) of patients in the radiotherapy group, 9 (36%) in the cryoablation group, and 19 (76)% in the cryoablation- radiotherapy group did not require narcotic medications.Conclusions
The addition of radiotherapy to cryoablation favorably impacts on perceived pain, with a favorable toxicity profile. However, our data should be interpreted with caution and could serve as a framework around which to design future trials. 相似文献8.
9.
Alberto L'Abbate Gemma Macchia Pietro D'Addabbo Angelo Lonoce Doron Tolomeo Domenico Trombetta Klaas Kok Christoph Bartenhagen Christopher W. Whelan Orazio Palumbo Marco Severgnini Ingrid Cifola Martin Dugas Massimo Carella Gianluca De Bellis Mariano Rocchi Lucia Carbone Clelia Tiziana Storlazzi 《Nucleic acids research》2014,42(14):9131-9145
The mechanism for generating double minutes chromosomes (dmin) and homogeneously staining regions (hsr) in cancer is still poorly understood. Through an integrated approach combining next-generation sequencing, single nucleotide polymorphism array, fluorescent in situ hybridization and polymerase chain reaction-based techniques, we inferred the fine structure of MYC-containing dmin/hsr amplicons harboring sequences from several different chromosomes in seven tumor cell lines, and characterized an unprecedented number of hsr insertion sites. Local chromosome shattering involving a single-step catastrophic event (chromothripsis) was recently proposed to explain clustered chromosomal rearrangements and genomic amplifications in cancer. Our bioinformatics analyses based on the listed criteria to define chromothripsis led us to exclude it as the driving force underlying amplicon genesis in our samples. Instead, the finding of coexisting heterogeneous amplicons, differing in their complexity and chromosome content, in cell lines derived from the same tumor indicated the occurrence of a multi-step evolutionary process in the genesis of dmin/hsr. Our integrated approach allowed us to gather a complete view of the complex chromosome rearrangements occurring within MYC amplicons, suggesting that more than one model may be invoked to explain the origin of dmin/hsr in cancer. Finally, we identified PVT1 as a target of fusion events, confirming its role as breakpoint hotspot in MYC amplification. 相似文献
10.
Filippo Alongi Elena Clerici Sara Pentimalli Pietro Mancosu Marta Scorsetti 《Reports of Practical Oncology and Radiotherapy》2012,17(5):262-268
AimTo show our preliminary experience in using TrueBeam with RapidArc technology and FFF beam for stereotactic re-irradiation of nasopharyngeal carcinoma.BackgroundThanks to new advanced techniques, as well as intensity modulated radiation therapy, it is possible to approach head and neck recurrences in selected patients. Volumetric Modulated Arc Therapy (VMAT) in its RapidArc® format, permits to reduce significantly the time to deliver complex intensity modulated plans, allowing to treat hypofractionated regimes within a few minutes. With TrueBeam it is possible to perform photon beams without usage of the flattening filter. It seems possible to expect a reduction of out-of-field dose when flattening filter free (FFF) beams are used. While research into the physics domain for FFF beams is increasing, there are very few clinical data where FFF beams are applied in clinical practice.Materials and methodsWe present here the cases of 4 patients with local or regional recurrence of nasopharyngeal carcinoma. All patients were treated using TrueBeam with RapidArc technology and FFF beam for stereotactic hypofractionated re-irradiation.ResultsAll patients concluded SBRT and showed good tolerability. During follow-up, complete response at imaging evaluation (PET and/or MRI) for all treated patients was documented.ConclusionsOur preliminary experience using TrueBeam with RapidArc technology and FFF beam for stereotactic hypofractionated re-irradiation of nasopharyngeal carcinoma was safe and effective in all 4 treated patients. Longer follow-up and a larger population of study is needed to confirm these promising results. 相似文献