Biology subjects

Vieira, R. P.

Publications and source records attributed to Vieira, R. P..

3 recordsLinked to original sources

bioRxiv2024

Effects of Hydrolyzed Collagen as a Dietary Supplement on Fibroblast Activation: A Systematic Review

PurposeOur objective was to conduct a systematic review of the effects of hydrolyzed collagen supplementation on the proliferation and activation of fibroblasts. MethodsThe search was conducted for journals that published articles in the English language, peer-reviewed, meeting the following criteria: a) randomized clinical trials, b) randomized studies in animals or humans, c) in vitro studies, d) studies using hydrolyzed collagens or collagen peptides, d) studies assessing alterations on fibroblasts as primary or secondary outcome. We utilized the main journal databases PUBMED/WEB OF SCIENCE and ongoing reviews by PROSPERO. For bias risk and methodological quality, we used an adaptation of the Downs and Black checklist. Our review followed the PRISMA checklist, conducted from February 2024 to the first week of March 2024, by two independent researchers (P.A.Q.I. and R.P.V.). ResultsEleven studies were included in this review, where our findings reinforce the notion that hydrolyzed collagens or collagen peptides at concentrations of 50-500 g/ml are sufficient to stimulate fibroblasts in human and animal tissues without inducing toxicity. Different enzymatic processes may confer distinct biological properties to collagens, allowing for scenarios favoring fibroblast promotion or antioxidant effects. Lastly, collagens with lower molecular weights exhibit greater bioavailability to adjacent tissues. ConclusionHydrolyzed collagens or collagen peptides with molecular sizes ranging from <3 - 3000 KDa promote the stimulation of fibroblasts in human tissues.

cell biology↗

bioRxiv2020

Immunoregulatory effects of Imuno TF (transfer factors) on Th1/Th2/Th17/Treg cytokines

Transfer factors are known since 1955 due to their activities on the immune system. Although the reports on the effects on diverse immune mechanisms, their role on Th1, Th2, Th17 and Treg responses was still not described. In this sense, the present work focused on the evaluation of such immune responses. For that, human lymphocytes, and mice thymic, splenic and Peyers cells were stimulated with Lipopolysaccharides and Concanavalin A, and then treated with isolated transfer factors (Imuno TF(R)). The culture medium was harvested and the quantification of Th1 cytokines (IL-2 and IFN-{gamma}), Th2 cytokines (IL-4, IL-5, and IL-13), Th17 cytokine (IL- 17), Treg cytokine (IL-35), inflammatory cytokines (IL-6 and TNF-), and anti-inflammatory cytokine (IL-10) was performed, as well as the quantification of mRNA levels. Imuno TF(R) positively regulated Th1 cytokines, while decreased Th2 cytokines. It also increased levels of mRNA and secretion of the anti-inflammatory cytokine IL-10, whereas it reduced levels of mRNA and the secretion of pro-inflammatory cytokines IL-6 and TNF-. Finally, it reversed the hypersecretion of IL-17 and did not promote significant changes in IL-35 secretion. This highlights the role of Imuno TF(R) in the regulation of the immune responses.

immunology↗

bioRxiv2019

A framework for the development of a global standardised marine taxon reference image database (SMarTaR-ID) to support image-based analyses

Video and image data are regularly used in the field of benthic ecology to document biodiversity. However, their use is subject to a number of challenges, principally the identification of taxa within the images without associated physical specimens. The challenge of applying traditional taxonomic keys to the identification of fauna from images has led to the development of personal, group, or institution level reference image catalogues of operational taxonomic units (OTUs) or morphospecies. Lack of standardisation among these reference catalogues has led to problems with observer bias and the inability to combine datasets across studies. In addition, lack of a common reference standard is stifling efforts in the application of artificial intelligence to taxon identification. Using the North Atlantic deep sea as a case study, we propose a database structure to facilitate standardisation of morphospecies image catalogues between research groups and support future use in multiple front-end applications. We also propose a framework for coordination of international efforts to develop reference guides for the identification of marine species from images. The proposed structure follows the Darwin Core standard to allow integration with existing databases. We suggest a management framework where high-level taxonomic groups are curated by a regional team, consisting of both end users and taxonomic experts. We identify a mechanism by which overall quality of data within a common reference guide could be raised over the next decade. Finally, we discuss the role of a common reference standard in advancing marine ecology and supporting sustainable use of this ecosystem.

ecology↗