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Ellen Arthur to E. Canciani
No full textLetter from Ellen Arthur, Ehrenreich Photo-Optical Industries, Inc. to E. Canciani, October 10, 1973https://lawcommons.lclark.edu/iwc_correspondence_1-1/1061/thumbnail.jp
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Ellen Arthur to E. Canciani
No full textLetter from Ellen Arthur, Ehrenreich Photo-Optical Industries, Inc. to E. Canciani, October 10, 1973https://lawcommons.lclark.edu/iwc_correspondence_1-1/1061/thumbnail.jp
ANALISI IMMUNOISTOCHIMICA E MOLECOLARE DEL PATTERN DI RIMODELLAMENTO OSSEO NELL¿ALVEOLO POST-ESTRATTIVO
Full text linkAnalisi immunoistochimica e molecolare del pattern di rimodellamento osseo nell’alveolo post-estrattivo
SCOPO
Il sito dell’alveolo post-estrattivo è un modello ampiamente utilizzato nello studio del rimodellamento osseo fisiologico o patologico e del comportamento di biomateriali per la rigenerazione ossea.
Lo scopo di questo progetto è stato quello di caratterizzare il pattern morfologico e molecolare dei marker coinvolti nel rimodellamento osseo alveolare, prima e dopo l’estrazione dentale, ed eventualmente in combinazione con un biomateriale utilizzato per preservare l’anatomia del sito ai fini riabilitativi.
MATERIALI E METODI
Per questo studio sono stati arruolati 36 pazienti, suddivisi in 3 gruppi indipendenti: osso alveolare (OA, n=14), guarigione spontanea (GS, n=10) e biomateriale (B, n=12). Durante la seduta di estrazione dentaria sono state raccolte 2 piccole biopsie per paziente per effettuare l’analisi morfologica (tessuto decalcificato) e molecolare (mRNA retro-trascritto in cDNA e Real Time-PCR) (gruppo OA). Dopo 4-6 mesi dall’estrazione dentale, sono state prelevate 3 biopsie per paziente, in concomitanza dell’inserimento dell’impianto dentale, nel sito guarito spontaneamente (GS) o mediante biomateriale (B) (idrossiapatite arricchita con magnesio). Per ogni gruppo sono state effettuate le stesse analisi del gruppo OA e l’analisi istomorfometrica (tessuto calcificato). L’analisi morfologica ha previsto: colorazione Ematossilina/Eosina per osservare un eventuale infiltrato infiammatorio, colorazione immunoistochimica dei fattori caratterizzanti il pattern di rimodellamento osseo (TNF-α, IL-6, RANK, RANKL e OPG), espressa come marcatura percentuale. L’analisi molecolare è stata effettuata sugli stessi marcatori normalizzati sul gene housekeeping 18S. Sui tessuti ottenuti per usura, è stata valutata l’osteointegrazione del biomateriale e la componente minerale mediante la valutazione delle frazioni di volume (stereologia). Per ciascun parametro sono state calcolate la media e la deviazione standard; è stato utilizzato il test di Kruskal Wallis (p<0,05) per valutare le eventuali differenze tra i 3 gruppi per ogni parametro e successivo test post hoc di Wilcoxon (p< 0,05/3).
RISULTATI
All’osservazione i campioni raccolti non presentavano né anomalie strutturali né infiltrato infiammatorio. Sia l’analisi immunoistochimica (AI) che molecolare (AM) ha mostrato un incremento per tutti i biomarker. AI: I tre gruppi erano significativamente differenti per il marcatore TNF-α (p<0.05), RANK (p<0.01), IL-6 e RANKL (p<0.001). Il test post hoc ha mostrato una differenza tra OA e B per RANK (p≤ 0.01), IL-6 e RANKL (p ≤0.001); tra GS e B per IL-6 (p≤0.01). AM: Il test di Kruskal Wallis ha mostrato differenze tra i gruppi per IL-6 (p≤0.05), RANKL e OPG (p≤0.001); il test post hoc ha riscontrato una significativa differenza tra OA e B per IL-6 (p≤0.01); OA e GS per RANKL e OPG (p≤0,001); tra GS e B per IL-6 e RANKL (p≤0,01), OPG (p≤0,001). Il rapporto RANKL/OPG ha mostrato una tendenza alla riduzione dell’osteoclastogenesi nel gruppo B. L’analisi istomorfometrica ha mostrato un’alta percentuale di componente mineralizzata nel gruppo con il biomateriale; tutte le particelle innestate erano circondate da osso rigenerato che creava ponti tra di esse.
CONCLUSIONI
Rispetto al rimodellamento fisiologico tutti i marker indagati hanno mostrato un incremento in entrambi i gruppi in fase di guarigione dell’alveolo post-estrattivo. Nei siti trattati con il biomateriale si è osservato un aumento della citochina IL-6 ed una diminuzione di RANK, RANKL e OPG rispetto alla guarigione spontanea. Questo può significare un rallentamento della ricostituzione del sito anatomico, dovuto ad una possibile down-regulation dell’osteoclastogenesi. Tuttavia, l’analisi della struttura dell’alveolo ha mostrato una buona rigenerazione ossea, in entrambi i gruppi; pertanto il biomateriale analizzato può essere considerato un valido ausilio per la preservazione dell’alveolo post-estrattivo.Immunohistochemical and molecular analysis of bone remodelling pattern in alveolar socket.
AIM
Following tooth extraction, the alveolar bone remodelling process starts.
The aim of this research project was to characterize the molecular and morphological aspects of the alveolar bone remodelling pattern before and after dental extraction and in conjunction with the use of hydroxyapatite enriched with magnesium (Mg-e HA) to preserve the post-extractive alveolar socket.
MATERIALS AND METHODS
Thirty-six patients, divided in three groups, were enrolled in this study. The studied groups were: alveolar bone (OA, n=14), spontaneous healing (GS, n=10) and biomaterial (B, n=12). The biopsies for morphological and molecular analyses were harvested during the extraction tooth session (group OA) or 4-6 months later (GS, B). In GS group, patients recovered spontaneously, while in B group Mg-e HA granules were grafted to avoid the collapse of post-extraction socket. For each group, one specimen was processed for Haematoxylin and Eosin staining and immunohistochemistry for TNF-α, IL-6, RANK, RANKL and OPG. Another specimen was processed to evaluate the gene expression of the same biomarkers by Real-Time PCR (mRNA retro-transcript into cDNA). Data were normalized on housekeeping gene 18s. In GS and B groups, ground sections were obtained to evaluate the mineral component by mean of stereological analyses.
For each parameter, statistical analyses were performed to evaluate the differences among the three groups (Kruskal Wallis, significance for p<0.05); post hoc tests were made by Wilcoxon tests (p<0.05/3).
RESULTS
Samples harvested from each group presented a normal structure, without evident inflammatory infiltrate. Immunohistochemical (IA) and molecular analysis (MA) showed an increment for all biomarkers. IA: The three groups were significantly different for markers TNF-α (p<0.05), RANK (p<0.01), IL-6 e RANKL (p<0.001). Post hoc tests showed a difference between OA and B for RANK (p≤ 0.01), IL-6 and RANKL (p ≤0.001); between GS and B for IL-6 (p≤0.01). MA: Kruskal Wallis test showed a difference among groups for IL-6 (p≤0.05), RANKL and OPG (p≤0.001); post hoc tests revealed a significant difference between: OA and B for IL-6 (p≤0.01); OA and GS for RANKL and OPG (p≤0.001); GS and B for IL-6 and RANKL (p≤0.01), OPG (p≤0.001). RANKL/OPG ratio showed a tendency towards a reduced osteoclastogenesis in group B. Histomorphometry revealed a high percentage of mineralized tissue in the grafted sites; all the residual granules were surrounded by newly formed bone, consisting in regenerated bone bridges.
CONCLUSION
Both post-extractive groups had an increase of all analysed biomarkers in respect of the physiological remodelling pattern. In the grafted sites, IL-6 values were higher than in the spontaneous healing group; in contrast RANK, RANKL and OPG were slightly lower. The present data may suggest a slowing down in the restoration of the anatomical site, possibly due to a down regulation in the osteoclastogenesis. However, the tissue composition of the grafted alveolar socket showed a good bone regeneration in both groups. Therefore, the current biomaterial could be considered a useful tool for alveolar socket preservation
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
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