1,721,012 research outputs found
Oxytocin receptor signaling in myoepithelial and cancer cells
No full textOxytocin (OT) plays a crucial role as a mediator of breast myoepithelial cell contraction, the process responsible for the ejection of milk during lactation, and is also involved in myoepithelial cell proliferation and postpartum mammary gland proliferation. Furthermore, although a number of breast cancer cells have oxytocin receptors (OTRs), it has been reported that OT stimulates, inhibits, or has no effect on cell proliferation. As these different effects seem to be mediated by different signaling pathways elicited by OTR stimulation, we here review the regulation of OTR signaling in different cell systems and discuss how understanding the molecular basis of receptor coupling specificity has become extremely important for understanding the role played by OTRs in regulating cell growth
Automated evaluation of mature bone component in alveolar biopsies following pre-implant guided bone regeneration procedure
No full textIntroduction. Making a dental implant means to put a hollow
screw with a tooth on top in the dental alveolus that
often is completely necrotic. Osteointegration and the quantity
and quality of bone available in the site of implant is a
crucial step for the stability of the protesis and the success
of the rehabilitation.
The aim of the study was to evaluate 24 biopsy from the
dental alveolus of 20 patients who underwent “Guided
Bone Regeneration” procedure with biocompatible material
(heterologous bone powder or synthetic powder) 6 months
following the treatment in order to determine the percentage
of mature bone. All the specimens were first analyzed by an expert pathologist and then by an automatic procedure
in order to determine an accurate cut off value which could
predict the implant success.
Material and methods. We used a digital microscope (Olympus
“slide Digital virtual microscopy”) with a proper
software (“dot slide” software) to scan all the specimens at
10X magnification to obtain VSI (Virtual Slide Image) files.
On scanned images the percentage of integrated bone was
determined by two different procedures:
A) we captured all images from dot slide’s VSI files and
measured the areas of each specimen by manual drawing
using “dot slide” instrument from the menu bar. It took
about one hour and half for each biopsy;
B) we captured the images from VSI files in the same way
but we converted VSI files in Jpg. These images were
analyzed using another software called “Image-Pro Plus”
by Media Cybernetics with a settings for automatic recognition
and measurements of selected areas. With this approach
we could evaluate the percentage of mature bone
for each biopsy in 10 minutes, and no special expertise
was required.
Several stains such as Trichrome and Von Kossa were tested
to give the best colour contrast between the different areas,
but Hemathoxilin and eosin gave the best result.
Results. The percentages of mature bone recognized using
the different approaches were similar and almost overlapping
with those reported by the expert pathologist, with a
variability of 5-10%. Inflammation, granulation tissue and
presence of osteoblasts/osteoclasts at the periphery of the
mature bone could play an additional important role on the
implant success and should be described.
Conclusions. Determining an exact cut off level of regenerated
vs. necrotic bone with rapid and automated procedure
would be important not only for objectively predicting the
implant success but also for testing different materials to be
used in pre-implant therapy
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
Esame istopatologico in alternativa allo striscio citologico per l’esame del brushing delle vie biliari
No full textIntroduzione. La citologia su striscio delle vie biliari extraepatiche
effettuata con spazzolino (brushing endoscopico)
è il metodo più utilizzato per la valutazione delle lesioni delle
vie biliari extraepatiche, ma presenta scarsa sensibilità. Per
migliorarne la potenzialità diagnostica, presentiamo una nuova
ed originale metodica che permette di effettuare un esame
citologico ottimale del materiale ago-aspirato.
Metodi. Lo spazzolino viene immediatamente immerso in
metanolo e inserito nelle biocassette per l’inclusione in
paraffina. Vengono tagliate delle sezioni parallele e consecutive
lungo l’asse maggiore, fino al core metallico; successivamente
il blocco di paraffina viene ruotato di 180° e nuove
sezioni vengono effettuate sul lato opposto. Le sezioni, colorate
in Ematossilina e Eosina e con Alcian Blue Mucine,
hanno mostrato piccoli frammenti di mucosa, di cellule infiammatorie
aggregate o di carcinoma, con un’ottima fissazione,
permettendo una diagnosi definitiva accurata in
quasi la totalità dei casi esaminati. Infatti 112 campioni citologici
di brushing endoscopici delle vie biliari extraepatiche
(67 M; 45 F), raccolti all’Ospedale “Molinette”, Università di
Torino, tra Gennaio 2002 e Agosto 2006, sono stati inclusi
nel nostro studio. Tutti i pazienti avevano una diagnosi
definitiva istologica e un follow-up clinico medio di 21 mesi.
Risultati. Confrontando questa originale metodica su 112
casi consecutivi di brushing endoscopico con la diagnosi istologica
su pezzo operatorio, abbiamo osservato: 87% di sensibilità,
100% di specificità, 100% di valore predittivo positivo
(VPP) e 91% di valore predittivo negative (NPV). La
metodica inoltre, confrontata con la diagnosi clinica dopo almeno
6 mesi di follow-up, ha mostrato: 88% sensibilità,
100% specificità, 100% VPP e 96% VPN.
Conclusioni. In conclusione questa nuova metodica è altamente
sensibile e specifica, limitando all’1% le diagnosi non
idonee, con una concordanza con la diagnosi istologica pari
all’88% (K-value)
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