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Fabianni M. Apolonio Annalisa Mazzoni Valeria Angeloni Polliana M. C. Scaffa Spartaco Santi Vicente de Paulo A. Saboia Franklin R. Tay David H. Pashley Lorenzo Breschi 《European journal of oral sciences》2017,125(2):168-172
Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time. 相似文献
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Fátima Jorge Miguel A. Carretero Vicente Roca Robert Poulin Ana Perera 《Parasitology research》2013,112(12):4001-4007
Parasitological analyses are often based on invasive methodologies, involving host sacrifice, raising ethical and conservation issues. However, alternative non-invasive approaches may not be always applicable due to the location of the parasite in the host tissue or the quality and reliability of the non-invasive sample per se. In this study, we compare the differences in detectability of intestinal parasites in reptiles using the classical invasive approach (intestine dissection), versus a non-invasive procedure (faecal examination), collected from the same individual host. Our results showed significantly lower detectability of helminths in faeces versus the intestine. Moreover, the number of parasites found in faeces was not explained either by the intensities found in the respective intestine or by the host identity. Several factors may explain the lack of association between the two types of samples, but more importantly, our results highlight the randomness of the presence of parasites in faeces. Even if it is not recommended that comparative studies of either parasite abundance or parasite communities be conducted on the basis of faecal samples, there are other types of studies (i.e. genetic) that can be performed with this source of information, thus avoiding the sacrifice of the host. Due to their wide spectrum of life stages and localization in the host tissue, parasites are challenging candidates for non-invasive sampling and consequently, parasitological methodologies should be carefully selected according to the objective of the study. 相似文献
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Lubeiro Alba Fatjó-Vilas Mar Guardiola Maria Almodóvar Carmen Gomez-Pilar Javier Cea-Cañas Benjamin Poza Jesús Palomino Aitor Gómez-García Marta Zugasti Jone Molina Vicente 《European archives of psychiatry and clinical neuroscience》2020,270(4):433-442
European Archives of Psychiatry and Clinical Neuroscience - A deficit in task-related functional connectivity modulation from electroencephalogram (EEG) has been described in schizophrenia. The use... 相似文献