1,721,386 research outputs found
Portrait of Frank M. Agostini
No full textReproduction of a portrait of Frank M. Agostini, a student at Cape Fear Military Academy from 1868-1869, in his uniform
Portrait of Frank M. Agostini
No full textReproduction of a portrait of Frank M. Agostini, a student at Cape Fear Military Academy from 1868-1869, in his uniform
Raccolta sistematica degli orientamenti ufficiosi del Tribunale di Milano in tema di omologazione ed iscrizione di atti societari
No full textGian Matteo Giberti (1495-1543)
No full textAtti del convegno di studi sul vescovo veronese. Gli interventi illustrano la sua figura e la sua azione come datario vaticano prima e indi come vescovo dei Verona, la cui azione pastorale anticipò la linea espressa dal Concilio di Trent
Ferritin nanocages for theranostic applications
Full text linkFerritin is a ubiquitous protein involved in iron storage composed of 24 subunits assembled in a hollow spherical nano-cage architecture. Channels formed between the intersection of peptide subunits are lined with polar aminoacids and allow for the entry and exit of cations. Ferritin can be successfully used as an highly biocompatible nanocarrier, due to the ability of being recognized and uptaken by TfR-1 overexpressing tumour cells. Furthermore, both inner or outer surface can be easily functionalized conferring multiple functionalities onto a single molecule. For these reasons, ferritins are emerging as novel biotech platforms for biomedical applications (both diagnostical and therapeutic) due to their ability to encapsulate cargo molecules, broad functionalization possibilities and selective targeting properties.
In this framework, the present work has been focused on the development and characterization of engineered recombinant mammalian and archaeal ferritin constructs to expand the scope of their nanotechnological applications.
With the aim of investigating the biological and biophysical properties of prokaryotic homopolymers and characterizing the permeability of the prokaryotic protein shell toward diffusants, two ferritins from Archaea have been chosen as model. A set of engineered mutants of Pyrococcus furiosus ferritin (Pf-Ft) and Archaeoglobus fulgidus ferritin (Af-Ft) have been obtained by placing a reactive cysteine residue per subunit in the same topological positions either inside or outside the internal cavity. These mutants differ from each other by the aminoacid composition of ferritin channels and the related “open” versus “closed” ferritin architecture. The molecular diffusion through the ferritin cavity has been characterized by studying within these mutants the cysteine reactivity toward the bulky and negatively charged DTNB molecule (5,5'-dithiobis-2-nitrobenzoic acid).
Moreover, Archaeoglobus fulgidus ferritin has been genetically engineered by changing the surface exposed loop connecting helices B and C to mimic the sequence of the analogous human H-chain ferritin loop. This novel “humanized” chimeric construct (named HumAf-Ft) thus combines the unique open structure and self-assembly properties of Af-Ft with the typical humanH-ferritin ability to bind the Transferrin Receptor TfR-1, which is overexpressed in several types of tumor cells. HumAfFt has been structurally and biophysically characterized and the improved cellular uptake has been demonstrated on HeLa cell line.
Lastly, to exploit lanthanide fluorescence properties and develop an intrinsically fluorescent nanoparticle, a novel construct has been developed by genetically fusing at the C-terminal end of mouse H-ferritin a lanthanide binding tag (LBT). LBTs are short peptides that selectively bind lanthanide ions at low-nanomolar affinities and, due to the presence of a tryptophan residue, provide strong FRET sensitization. This novel construct (named HFt-LBT) has been designed by locating the tag inside the inner cavity, so that the lanthanide ions diffusing through the surface pores can eventually bind to the LBT sequence. HFt-LBT would thus act both as carrier targeted to TfR-1 receptor and as a FRET sensitizer. Fluorescence improvement and lanthanide binding properties have been investigated by spectrophotometric measurements using Tb+3 as lanthanide probe. The structural characterization has been carried out and cellular uptake by HeLa cell line has been assessed as well
Study of the role of the DOF transcription factor DAG1 in the control of seedling development in Arabidopsis thaliana
Full text linkSeedling development relies on environmental conditions; indeed, once seeds have germinated, they undergo photomorphogenesis or skotomorphogenesis, depending on the presence or absence of light. Photomorphogenesis is a multi-traits process characterised by inhibition of hypocotyl elongation, open and expanded cotyledons, and chloroplast development, whereas skotomorphogenesis is characterised by long hypocotyls and small unfolded cotyledons. Hypocotyl elongation is influenced by both environmental and hormonal cues and it has been extensively studied as a model for cell expansion. Nevertheless, the molecular network underlying this process is not yet fully elucidated.
The Arabidopsis Dof protein DAG1 (Dof Affecting Germination1) is a repressor of seed germination, and a key player of the seed-to seedling transition, a crucial developmental phase positively controlled by light, as well as by the phytohormones ABA (abscissic acid) and GA (gibberellins). Indeed, DAG1 controls the ratio of ABA and GA, which play opposite roles, as ABA represses germination whereas GAs promote it.
We have previously shown that inactivation of DAG1 affects inhibition of hypocotyl elongation. Indeed, light-grown dag1 mutant seedlings show significant shorter hypocotyls compared to the wild-type, suggesting that DAG1 is a negative component of this light-mediated process. To gain some insight into the molecular network in which DAG1 is involved, we have analysed the transcriptome profile of both dag1 and wild-type hypocotyls and seedlings. We have identified more than 250 genes that are differentially expressed in dag1 hypocotyls, and the analysis of this data suggests that DAG1 is mainly involved in promoting hypocotyl elongation. In addition, a number of the DE genes identified are correlated to the
response to ABA stimulus. ABA plays a role in inhibition of hypocotyl elongation, although the molecular mechanism remains unclear.
Therefore, we investigated the effect of ABA on hypocotyl development, and our results showed that ABA negatively controls cell expansion in hypocotyls, by acting on GA metabolism, and repressing auxin biosynthesis. Consistently, addition of exogenous ABA can revert the hypocotyl phenotype of dag1 mutant seedlings.
In conclusion, our results prove that DAG1 is likely to be an element of a molecular network which controls cell expansion by modulating hormonal response, namely auxin, ABA and GAs
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
- …
