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The presence of natural organic matter such as humic acid (HA) can influence the behavior of graphene oxide (GO) in the aquatic environment. In this study, zebrafish embryos were analyzed after 5 and 7 days of exposure to GO (100 mg L-1) and HA (20 mg L?1) alone or together. The results indicated that, regardless of the presence of HA, larvae exposed to GO for 5 days showed an increase in locomotor activity, reduction in the yolk sac size, and total length and inhibition of AChE activity, but there was no difference in enzyme expression. The statistical analysis indicated that the reductions in total larval length, yolk sac size, and AChE activity in larvae exposed to GO persisted in relation to the control group, but there was a recovery of these parameters in groups also exposed to HA. Larvae exposed to GO for 7 days did not show significant differences in locomotor activity, but the RT-PCR gene expression analysis evidenced an increase in the AChE expression. Since the embryos exposed to GO showed a reduction in overall length, they were submitted to confocal microscopy and their muscle tissue configuration investigated. No changes were observed in the muscle tissue. The results indicated that HA is associated with the toxicity risk modulation by GO and that some compensatory homeostasis mechanisms may be involved in the developmental effects observed in zebrafish. Made available in DSpace on 2019-11-29T00:38:10Z (GMT). No. of bitstreams: 1 CastroExplorinGraphene2019.pdf: 1588063 bytes, checksum: 442617336ba12bcfbf2332ea5e36872c (MD5) Previous issue date: 2019

Made available in DSpace on 2018-12-11T17:20:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-15 Natural Sciences and Engineering Research Council of Canada Bulk and surface properties are very important for materials used in biomedical applications. The development of new surface treatments, such as antibacterial coatings can directly affect the response of the surface. The purpose of this study was the development of antibacterial coating on the Ti7.5Mo alloy surface combining TiO2 nanotubes with silver nanoparticles incorporation using polydopamine assisted immobilization technique. Surface characterization analysis showed that silver nanoparticles were successfully immobilized. The concentration established was bactericidal, i.e., no bacteria grew after incubation. In vivo results showed that silver incorporation on the surface containing TiO2 nanotubes did not cause altered locomotor activity in zebrafish. On the other hand, it affected the cell adhesion on the surface. Thus, these results confirm the hypothesis that silver nanoparticles were totally incorporated to polydopamine on the surface containing TiO2 nanotubes and acted as the main mechanism the death of the bacteria by contact. UNESP–São Paulo State University School of Engineering Materials and Technology Department, Guaratinguetá UNICAMP – University of Campinas Faculty of Medical Sciences Department of Medical Genetics Colorado State University Department of Mechanical Engineering/School of Biomedical Engineering, Fort Collins Laval University Metallurgy and Materials Engineering Department of Mining UNESP–São Paulo State University School of Engineering Materials and Technology Department, Guaratinguetá Natural Sciences and Engineering Research Council of Canada: Bioengineering for the Innovation in Surgery Natural Sciences and Engineering Research Council of Canada: Canada Research Chair in Biomaterials

The RET S836S variant has been associated with early onset and increased risk for metastatic disease in medullary thyroid carcinoma (MTC). However, the mechanism by which this variant modulates MTC pathogenesis is still open to discuss. Of interest, strong linkage disequilibrium (LD) between RET S836S and 3'UTR variants has been reported in Hirschsprung's disease patients., info:eu-repo/semantics/published

BackgroundFourier transforms and their associated power spectra are used for detecting periodicities and protein-coding genes and is generally regarded as a well established technique. Many of the periodicities which have been found with this method are quite well understood such as the periodicity of 3 nt which is associated to codon usage. But what is the origin of the peculiar frequency multiplesk/21 which were reported for a tiny section of chromosome 2 inP. falciparum? Are these present in other chromosomes and perhaps in related organisms? And how should we interpret fractional periodicities in genomes?ResultsWe applied the binary indicator power spectrum to all chromosomes ofP. falciparum, and found that the frequency overtonesk/21 are present only in non-coding sections. We did not find such frequency overtones in any other related genomes. Furthermore, the frequency overtones were identified as artifacts of the way the genome is encoded into a numerical sequence, that is, they are frequency aliases. By choosing a different way to encode the sequence the overtones do not appear. In view of these results, we revisited early applications of this technique to proteins where frequency overtones were reported.ConclusionsSome authors hinted recently at the possibility of mapping artifacts and frequency aliases in power spectra. However, in the case ofP. falciparumthe frequency aliases are particularly strong and can mask the 1/3 frequency which is used for gene detecting. This shows that albeit being a well known technique, with a long history of application in proteins, few researchers seem to be aware of the problems represented by frequency aliases.