1,720,959 research outputs found
Sviluppo di nuovi radiotraccianti PET basati su inibitori di trasportatori di monocarbossilato per applicazioni teranostiche in oncologia.
No full textIl progetto, inquadrato nell’ambito della medicina nucleare, si pone l’obbiettivo di sintetizzare nuove molecole utilizzabili per effettuare terapia o diagnostica, in ambito oncologico, tramite l’impiego di radionuclidi.
Il progetto di ricerca si è incentrato in primo luogo sulla sintesi di piccole molecole fluorurate aventi come target biologico MCT1 (Mono Carboxylate Transporter 1). MCT1 è una proteina atta all’efflusso di lattato dall’ambiente cellulare a quello extracellulare che subisce una forte sovraespressione in determinate tipologie tumorali, e può quindi essere utilizzato come potenziale target biologico. La sintesi dei composti è stata guidata da uno screening in silico tramite esperimenti di docking effettuati partendo dai dati cristallografici di MCT1. La classe di derivati che ha ottenuto i risultati più promettenti dai test biologici preliminari effettuati è quella delle 3-carbossicumarine. Queste molecole, una volta marcate con fluoro-18, saranno testate come agenti diagnostici tramite l’utilizzo di tomografia ad emissione di positroni (PET).
La seconda parte del progetto di ricerca ha riguardato la sintesi di un composto bioconiugato contenente una porzione 3-carbossicumarinica (targeting vector) ed un noto agente chelante per il rame nominato “no3py”, separati da un linker consistente in una catena di polietilenglicole (PEG). Questo bioconiugato è stato progettato per mantenere l’affinità per MCT1 tramite la porzione cumarinica, e al contempo trasportare rame (II) tramite la formazione di un complesso con il chelante no3py che risulti stabile ed inerte. Il rame offre il vantaggio di avere diversi isotopi che possono essere usati in ambito clinico con finalità diverse, nello specifico rame-61 o rame-64 per scopo diagnostico e rame-67 per radioterapia.
L’ultimo topic affrontato riguarda lo sviluppo di nuovi chelanti macrociclici per il rame (II) basati sulla struttura di no3py. Sono stati sintetizzati tre nuovi leganti che presentano da 1 a 3 gruppi solfonici carichi negativamente (-SO3-), che producono una gamma di effetti sulle proprietà fisico-chimiche dei rispettivi complessi di rame. I nuovi chelanti e i loro complessi di rame(II) sono stati approfonditamente studiati in soluzione. I complessi metallici risultano tutti estremamente promettenti per future con applicazioni nell’ambito della medicina nucleare e non solo, in particolare per la loro straordinaria stabilità in un ampio intervallo di pH e la loro inerzia.The project is framed within the scope of nuclear medicine. The objective is to synthesize new molecules that can be used for therapy or diagnostics in oncology using radionuclides.
The research project initially focused on the synthesis of small fluorinated molecules targeting MCT1 (Mono Carboxylate Transporter 1). The synthesis was guided by previous in silico screening through docking experiments conducted on the crystallographic structure of MCT1. MCT1 is a protein responsible for the efflux of lactate from the intracellular environment to the extracellular space, and it is significantly overexpressed in certain types of tumors. These molecules, once labeled with fluorine-18, were designed to be used as diagnostic agents via positron emission tomography (PET). The class of derivatives that yielded the most promising results from preliminary biological tests was that of 3-carboxycoumarins.
Subsequently, the research project involved the synthesis of a bioconjugate containing a 3-carboxycoumarin portion (targeting vector) and a well-known copper chelator named “no3py,” separated by a linker consisting of a polyethylene glycol (PEG) chain. This bioconjugate was designed to maintain good affinity for MCT1 through the coumarin portion while simultaneously transporting copper (II) by forming a stable and inert complex. The choice of copper was guided by the possibility of using different isotopes for various functions: specifically, copper-61 or copper-64 for diagnostic purposes and copper-67 for radiotherapy.
The final topic addressed was the development of new macrocyclic chelators for copper (II). The introduction of a variable number of negatively charged groups (-SO3-) onto the base structure of the known chelator no3py produced a range of effects on the physicochemical properties of their respective copper complexes. The results from this part of the research project led to the synthesis of three new ligands for copper (II) that can be chosen to tune the desired properties in the final metal-complex, with potential applications not only in nuclear medicine
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Applications of Radiolabelled Curcumin and Its Derivatives in Medicinal Chemistry
Full text linkCurcumin is a natural occurring molecule that has aroused much interest among researchers
over the years due to its pleiotropic set of biological properties. In the nuclear medicine field,
radiolabelled curcumin and curcumin derivatives have been studied as potential radiotracers for the
early diagnosis of Alzheimer’s disease and cancer. In the present review, the synthetic pathways,
labelling methods and the preclinical investigations involving these radioactive compounds are
treated. The studies entailed chemical modifications for enhancing curcumin stability, as well as its
functionalisation for the labelling with several radiohalogens or metal radionuclides (fluorine-18,
technetium-99m, gallium-68, etc.). Although some drawbacks have yet to be addressed, and none
of the radiolabelled curcuminoids have so far achieved clinical application, the studies performed
hitherto provide useful insights and lay the foundation for further developments
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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