207 research outputs found

    Los Estudios del español sefardí (judeoespañol, ladino). Aportaciones, métodos y problemas actuales

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    Rassegna critica dei principali contributi allo studio del giudeospagnolo apparsi negli ultimi dieci ann

    Massive non-natural proteins structure prediction using grid technologies

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    Background The number of natural proteins represents a small fraction of all the possible protein sequences and there is an enormous number of pr oteins never sampled by nature, the so called "never born proteins" (NBPs). A fundamental question in this regard is if the ensemble of natural proteins possesses peculiar chemical and physical properties or if it is just the product of contingency coupled to functional selection. A key feature of natural proteins is thei r ability to form a well defined three-dimensional structure. T hus, the structural study of NBPs can help to understand if natural protein sequences were selecte d for their peculiar properties or if they are just one of the possible stable and functional ensembles. Methods The structural characterization of a huge number of random proteins cannot be approached experimentally, thus the problem has been tackled using a computational approach. A large random protein sequences library (2 × 10 ^4 sequences) was generated, discarding amino acid sequences with significant simi larity to natural proteins, and the corresponding structures were predicted using Rosetta. Given th e highly computational demanding problem, Rosetta was ported in grid and a user friendly job submission environment was developed within the GENIUS Grid Portal. Protein structures generated were analysed in terms of net charge, secondary structure content, surface/volume ratio, hydrophobic core composition, etc. Results The vast majority of NBPs, according to the Rosetta mode l, are characterized by a compact three-dimensional structure with a high secondary structure content. Structure compactness and surface polarity are comparable to those of natural proteins, suggesting similar stability and solubility. Deviations are observed in α helix- β strands relative content and inydrophobic core composition, as NBPs appear to be richer in helical structure and aromatic amino acids with respect to natural proteins. Conclusion The results obtained suggest that the abil ity to form a compact, ordered and water-soluble structure is an intrinsic property of polypeptides. The tendency of random sequences to adopt α helical folds indicate that all-α proteins may have emerged ea rly in pre-biotic evolution. Further, the lower percentage of aromatic residu es observed in natural proteins has important evolutionary implications as far as tolerance to mutati ons is concerned

    Overall Survival Following Anastomotic Leakage After Surgery for Carcinoma of the Esophagus and Gastroesophageal Junction: A Systematic Review

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    The effect of anastomotic leakage, in patients who underwent surgery for carcinoma of the esophagus and gastroesophageal junction, on overall survival (OS) is a debated and controversial topic. The aim of this systematic review was to clarify the impact of anastomotic leakage on long-term survival of patients with esophageal cancer undergoing esophagectomy. A systematic literature review was carried out from 2000 to 2022. We chose articles reporting data from patients who underwent surgery for carcinoma of the esophagus and gastroesophageal junction. Data regarding 1-, 3- and 5-year OS were analyzed. Twenty studies met the inclusion criteria, yielding a total of 9,279 patients. Analyzing data from selected studies, anastomotic leakage was found to be associated with decreased OS in 5,456 cases while in the remaining 3,823 it had no impact on long term survival (p<0.05). However, this result did not emerge from the other studies considered in the systematic review. Anastomotic leakage is a severe postoperative complication, which seems to have an impact on overall survival. However, the topic remains debated and not supported by all case series included in this systematic review

    Vineyard establishment under exacerbated summer stress: effects of mycorrhization on rootstock agronomical parameters, leaf element composition and root-associated bacterial microbiota

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    Aims Climate change imposes adaptation of viticulture in risk areas, such as the Mediterranean. Mycorrhization is a valid tool to reduce the impact of the expected temperature/drought increase. Aim of this work was to test the effects of mycorrhization on grapevine vegetative growth, element composition of soil/leaves, and microbiota of bulk soil/rhizosphere/endorhiza, in the field, under exacerbated summer stress conditions obtained by planting the rootstocks in June. Methods 118 rooted cuttings of 1103-Paulsen (Vitis berlandieri Ă— Vitis rupestris) were planted in Salento (Apulia, Southern Italy); about half of them were mycorrhized. Leaf Area Index, shoot growth and survival rate were monitored across two growing seasons. Leaf/shoot weight, chemical analysis of 25 elements, and 16S rRNA gene metabarcoding of bulk soil/rhizosphere/endorhiza were performed on subsamples. Results Mycorrhized plants showed significantly higher survival rate and growth, and accumulated significantly higher amounts of 18 elements. 27 endorhizal OTUs (representing ~20% of total sequences) were differently distributed (20 OTUs more abundant in mycorrhized plants); in the rhizosphere, instead, 12 OTUs (~2.5% of total sequences) were differently distributed. A few Actinobacterial OTUs were enriched by mycorrhization in the root endosphere; the same OTUs were the most correlated with the chemical elements, suggesting a role in element dynamics. These OTUs were not hub taxa of the co-occurrence network. Conclusions This work shed light onto the interactions between mycorrhiza and microbiome, in the context of plant element dynamics, which is useful to identify potential target candidates for biotechnological applications, thus moving towards a more sustainable, ecosystem-based viticulture

    Currículum, saberes y prácticas

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    Fil: Ferreyra, Horacio Ademar. Universidad CatĂłlica de CĂłrdoba. Facultad de EducaciĂłn; ArgentinaFil: Di Francesco, Adriana Carlota. Universidad CatĂłlica de CĂłrdoba. Facultad de EducaciĂłn; Argentin
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