Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto

About: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto is a based out in . It is known for research contribution in the topics: Population & Genus. The organization has 2143 authors who have published 3674 publications receiving 71071 citations. The organization is also known as: FFCLRP & FFCLRP-USP.

Biomimetic oxidation of praziquantel catalysed by metalloporphyrins

Abstract: This paper reports an HPLC–MS/MS investigation of praziquantel (anthelmintic agent) oxidation by iodosylbenzene in an organic medium, using iron(III) tetraarylporphyrins (where aryl = phenyl, pentafluorophenyl, 2-nitrophenyl, 2-trifluoromethylphenyl and mesityl) and manganese(III) tetraphenylporphyrin as catalysts. The majority of the oxidation products have been identified by sequential MS and NMR analyses. The selectivities of the oxidations by these cytochrome P-450 models are studied and compared. Time dependent reaction profiles suggest that with all the catalysts, the initial oxidation occurs predominantly at the 7-position. With Fe(T2TFMPP)Cl the yield and selectivity (64%) for 7-hydroxypraziquantel remain high even after 24 h reaction, whereas with the other catalysts this initial product is further oxidized to di- and trihydroxypraziquantel. The Fe(TFPP)Cl system results in the higher yield (11%) of cis - and trans -4′-hydroxypraziquantel, the major metabolites from in vivo and in vitro metabolism of praziquantel by cytochrome P-450 monooxygenases.

Effects of a Mixture of Growth Factors and Proteins on the Development of the Osteogenic Phenotype in Human Alveolar Bone Cell Cultures

Abstract: SUMMARY Strategies to promote bone repair have included exposure of cells to growth factor (GF) preparations from blood that generally include proteins as part of a complex mixture. This study aimed to evaluate the effects of such a mixture on different parameters of the development of the osteogenic phenotype in vitro. Osteoblastic cells were obtained by enzymatic digestion of human alveolar bone and cultured under standard osteogenic conditions until subconfluence. They were subcultured on Thermanox coverslips up to 14 days. Treated cultures were exposed during the first 7 days to osteogenic medium supplemented with a GFs 1 proteins mixture containing the major components found in platelet extracts [platelet-derived growth factor-BB, transforming growth factor (TGF)-b1, TGF-b2, albumin, fibronectin, and thrombospondin] and to osteogenic medium alone thereafter. Control cultures were exposed only to the osteogenic medium. Treated cultures exhibited a significantly higher number of adherent cells from day 4 onward and of cycling cells at days 1 and 4, weak alkaline phosphatase (ALP) labeling, and significantly decreased levels of ALP activity and mRNA expression. At day 14, no Alizarin red–stained nodular areas were detected in cultures treated with GFs 1 proteins. Results were confirmed in the rat calvaria–derived osteogenic cell culture model. The addition of bone morphogenetic protein 7 or growth and differentiation factor 5 to treated cultures upregulated Runx2 and ALP mRNA expression, but surprisingly, ALP activity was not restored. These results showed that a mixture of GFs 1 proteins affects the development of the osteogenic phenotype both in human and rat cultures, leading to an increase in the number of cells, but expressed a less differentiated state. (J Histochem Cytochem 56:629–638, 2008)

Protein Engineering Strategies to Expand CRISPR-Cas9 Applications

Abstract: The development of precise and modulated methods for customized manipulation of DNA is an important objective for the study and engineering of biological processes and is essential for the optimization of gene therapy, metabolic flux, and synthetic gene networks. The clustered regularly interspaced short palindromic repeat- (CRISPR-) associated protein 9 is an RNA-guided site-specific DNA-binding complex that can be reprogrammed to specifically interact with a desired DNA sequence target. CRISPR-Cas9 has been used in a wide variety of applications ranging from basic science to the clinic, such as gene therapy, gene regulation, modifying epigenomes, and imaging chromosomes. Although Cas9 has been successfully used as a precise tool in all these applications, some limitations have also been reported, for instance (i) a strict dependence on a protospacer-adjacent motif (PAM) sequence, (ii) aberrant off-target activity, (iii) the large size of Cas9 is problematic for CRISPR delivery, and (iv) lack of modulation of protein binding and endonuclease activity, which is crucial for precise spatiotemporal control of gene expression or genome editing. These obstacles hinder the use of CRISPR for disease treatment and in wider biotechnological applications. Protein-engineering approaches offer solutions to overcome the limitations of Cas9 and generate robust and efficient tools for customized DNA manipulation. Here, recent protein-engineering approaches for expanding the versatility of the Streptococcus pyogenes Cas9 (SpCas9) is reviewed, with an emphasis on studies that improve or develop novel protein functions through domain fusion or splitting, rational design, and directed evolution.

Copaiba oil suppresses inflammatory cytokines in splenocytes of C57Bl/6 mice induced with experimental autoimmune encephalomyelitis (EAE).

Abstract: Experimental autoimmune encephalomyelitis (EAE) is a murine autoimmune disease used to study multiple sclerosis. We have investigated the immunomodulatory effects of copaiba oil (100, 50 and 25 µg/mL) on NO, H2O2, TNF-α, IFN-γ and IL-17 production in cultured cells from EAE-mice. Copaiba oil (100 µg/mL) inhibited H2O2, NO, IFN-γ TNF-α and IL-17 production spontaneously or after ConA and MOG35-55 stimulation. It is suggested that copaiba oil acts on the mechanism of development of EAE by IFN-γ, IL-17 and TNF-α inhibition, modulating the immune response on both Th1 and Th17 cells.