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Protein adsorption on a laser-modified titanium implant surface.
No full textPURPOSE: The aim of this study was to investigate the earlier phase of the osseointegration of a laser-treated implant surface in terms of human protein adsorption.
MATERIALS AND METHODS:
Titanium surfaces were divided into machined (M), sandblasted (SB), and laser-treated (LT). The LT surfaces were created with an Nd diode-pumped laser in Q-switching, whereas the SB were treated with Al2O3. An x-ray photoelectron spectroscopy (XPS) analysis of titanium surface was performed. Titanium discs were used for albumin and fibronectin adsorption evaluation through fluorescence intensity. Fibronectin evaluation was also made with Western Blot analysis on experimental implants.
RESULTS:
LT discs appeared to trigger a higher albumin and fibronectin adsorption with a regular pattern. The mean count of albumin adsorption was 0.29 and 3.8 for SB and LT, respectively (P = 0.016), whereas fibronectin values were 0.67 and 4.9 for (SB) and (LT) titanium (P = 0.02). XPS analysis showed that titanium, oxygen, carbon, and nitrogen were found on all 3 surfaces.
CONCLUSION:
Laser-engineered porous titanium surface seems to promote, in vitro, the adsorption of albumin and fibronectin more than sandblasted (SB) or machined (M) implants
Can enzymatic antioxidant defences in liver discriminate between wild and sea cage-reared Bluefin Tuna quality?
No full textBluefin Tuna (Thunnus thynnus L.) is a fish species of high nutritional and commercial value that is increasingly farmed in the Mediterranean basin. Oxidative stress research in aquaculture is particularly important in the assessment of both the health of farmed fish and seafood quality. Reactive oxygen species (ROS) are able to start the lipid peroxiclation process which is potentially dangerous in fish, since they contain a high percentage of n-3 polyunsaturated fatty acids, in particular C20:5 n-3 and C22:6 n-3, which account for most of seafood's nutritional quality. The study of the antioxiclant system and how the various components interact to delay post-harvest lipid peroxidation covers both the improvement of quality and the extension of shelf life of the fresh tuna product.
In this study, hepatic antioxidant enzymes (catalase-CAT, superoxide dismutase-SOD and glutathione peroxidase-GPx) and lipid peroxidation levels (TBARS) of wild and sea cage-reared tunas were investigated. The aim was to examine the possible oxidative stress state of wild tunas killed by different fishing methods, compared with reared specimens exposed to different periods of confinement but killed by the same method.
No significant differences between wild specimens were found in relation to catching techniques. A significant depletion was observed in liver SOD activity in reared tunas (5.00 U/mg protein) in comparison with wild specimens (5.90 U/mg protein). No differences in liver CAT activity between wild and reared tunas were found. In reared specimens we observed an oxidative stress state indicated by an increase in GPx activity (104.70 U/mg protein and 0.83 U/mg protein in reared and wild tunas, respectively). A significantly higher liver lipid content was observed in reared tunas, but no significant differences between wild and reared tunas in terms of TBA reactive substances content were found (2.03 vs 2.02 micrornol TBARS/rng lipid). Our results suggest that the increased GPx activity leads to the suppression of lipid peroxiclation in liver of reared tunas. This is the first time that antioxiclant enzyme activities have been assayed in Bluefin Tuna and the stress state seems to be related to the diet of reared specimens rather than to their confinement, as indicated by the absence of differences in the antioxiclant activities related to the period of confinement
Identification of new compounds that trigger apoptosome-independent caspase activation and apoptosis
No full textComparison of the primary stabilities of conical and cylindrical endosseous dental implants: an in-vitro study
No full textThe aim of this study is to determine the differences in primary stability between conical and cylindrical dental implants. The insertion and removal torques were the parameters used to measure the primary stability of the implants. Ten conical and cylindrical dental implants were positioned in polyurethane foam blocks to simulate bone density classes D1, D2, D3 and D4. The insertion and removal torques were quantified using a digital torque gauge. The maximum insertion torque and the maximum removal torque measured for the D1 and D4 synthetic bone were significantly higher for the conical implants than the cylindrical implants. In this in-vitro model, conical implants show significantly higher primary stability than cylindrical implants for the D1 and D4 synthetic bone classes
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
Contaminazione da metalli in tracce in un sistema costiero Mediterraneo (laghetti di Marinello, Sicilia, Italia) e loro trasferimento lungo la rete trofica.
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