744 research outputs found
approach chemistry, functional and biological
Dithiocarbamates represent a class of compounds that were evaluated in different biomedical applications because of their chemical versatility. For this reason, several pharmacological activities have already been attributed to these compounds, such as antiparasitic, antiviral, antifungal activities, among others. Therefore, compounds that are based on dithiocarbamates have been evaluated in different in vivo and in vitro models as potential new antimicrobials. Thus, the purpose of this review is to present the possibilities of using dithiocarbamate compounds as potential new antitrypanosomatids-drugs, which could be used for the pharmacological control of Chagas disease, leishmaniasis, and African trypanosomiasis.publishersversionpublishe
Development of text mining tools for information retrieval and extraction from patents
[Excerpt] Biomedical literature is composed of a large and ever increasing number of publications, written in natural language. Patents are a relevant fraction of these publications, considered important sources of information due to all the curated information available in the documents, from the granting process. Although being real technological libraries, their unstructured data turns the search of information within these documents a challenging task. Biomedical text mining is a scientific field that explores this task, creating methodologies to search and structure the information in the biomedical literature. [...]info:eu-repo/semantics/publishedVersio
Partial characterization and anticoagulant activity of a heterofucan from the brown seaweed Padina gymnospora
The brown algae Padina gymnospora contain different fucans. Powdered algae were submitted to proteolysis with the proteolytic enzyme maxataze. The first extract of the algae was constituted of polysaccharides contaminated with lipids, phenols, etc. Fractionation of the fucans with increasing concentrations of acetone produced fractions with different proportions of fucose, xylose, uronic acid, galactose, and sulfate. One of the fractions, precipitated with 50% acetone (v/v), contained an 18-kDa heterofucan (PF1), which was further purified by gel-permeation chromatography on Sephadex G-75 using 0.2 M acetic acid as eluent and characterized by agarose gel electrophoresis in 0.05 M 1,3 diaminopropane/acetate buffer at pH 9.0, methylation and nuclear magnetic resonance spectroscopy. Structural analysis indicates that this fucan has a central core consisting mainly of 3-ß-D-glucuronic acid 1-> or 4-ß-D-glucuronic acid 1 ->, substituted at C-2 with alpha-L-fucose or ß-D-xylose. Sulfate groups were only detected at C-3 of 4-alpha-L-fucose 1-> units. The anticoagulant activity of the PF1 (only 2.5-fold lesser than low molecular weight heparin) estimated by activated partial thromboplastin time was completely abolished upon desulfation by solvolysis in dimethyl sulfoxide, indicating that 3-O-sulfation at C-3 of 4-alpha-L-fucose 1-> units is responsible for the anticoagulant activity of the polymer.Universidade Federal do Rio Grande do Norte Departamento de Bioquímica Laboratório de GlicobiologiaUniversidade Federal do Rio Grande do Norte Departamento de Bioquímica Laboratório de Biotecnologia de Polímeros NaturaisUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de BioquímicaUNIFESP, EPM, Depto. de BioquímicaSciEL
In Vitro Validation of Antiparasitic Activity of PLA-Nanoparticles of Sodium Diethyldithiocarbamate against Trypanosoma cruzi
Funding Information: This research was funded by Global Health and Tropical Medicine: Grant number IHMT-UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017, FCT-Portugal.We would like to thank João Aristeu da Rosa and Aline Rimodi Rimeiro at UNESP (Universidade Estadual de São Paulo) Araraquara (Brazil) for offering four different strains of T. cruzi. JWFO and MFAS give thanks to their financial support (PhD and post-doctoral fellowships) provided by Capes/Brazil; MSS, AASJ, and HAOR give thanks to CNPq/Brazil for the Research Grant (Bolsa de Produtividade). We would also like to thank the Department of Materials Engineering at UFRN for affording us the use of their scanning electron microscope, and the Department of Biochemistry at UFRN for affording us the use of their culture room. We thank Laysa Ohana for reviewing and editing the English version of the manuscript. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Trypanosoma cruzi is a protozoan parasite responsible for Chagas disease, which affects millions around the world and is not treatable in its chronic stage. Sodium diethyldithiocarbamate is a compound belonging to the carbamate class and, in a previous study, demonstrated high efficacy against T. cruzi, showing itself to be a promising compound for the treatment of Chagas disease. This study investigates the encapsulation of sodium diethyldithiocarbamate by poly-lactic acid in nanoparticles, a system of biodegradable nanoparticles that is capable of reducing the toxicity caused by free DETC against cells and maintaining the antiparasitic activity. The nanosystem PLA-DETC was fabricated using nanoprecipitation, and its physical characterization was measured via DLS, SEM, and AFM, demonstrating a small size around 168 nm and a zeta potential of around −19 mv. Furthermore, the toxicity was determined by MTT reduction against three cell lines (VERO, 3T3, and RAW), and when compared to free DETC, we observed a reduction in cell mortality, demonstrating the importance of DETC nanoencapsulation. In addition, the nanoparticles were stained with FITC and put in contact with cells for 24 h, followed by confirmation of whether the nanosystem was inside the cells. Lastly, the antiparasitic activity against different strains of T. cruzi in trypomastigote forms was determined by resazurin reduction and ROS production, which demonstrated high efficacy towards T. cruzi equal to that of free DETC.publishersversionpublishe
Antiproliferative activity of fucan nanogel
Sulfated fucans comprise families of polydisperse natural polysaccharides based on sulfated l-fucose. Our aim was to investigate whether fucan nanogel induces cell-specific responses. To that end, a non toxic fucan extracted from Spatoglossum schröederi was chemically modified by grafting hexadecylamine to the polymer hydrophilic backbone. The resulting modified material (SNFuc) formed nanosized particles. The degree of substitution with hydrophobic chains was close to 100%, as estimated by elemental analysis. SNFfuc in aqueous media had a mean diameter of 123 nm and zeta potential of −38.3 ± 0.74 mV, as measured by dynamic light scattering. Nanoparticles conserved their size for up to 70 days. SNFuc cytotoxicity was determined using the MTT assay after culturing different cell lines for 24 h. Tumor-cell (HepG2, 786, H-S5) proliferation was inhibited by 2.0%–43.7% at nanogel concentrations of 0.05–0.5 mg/mL and rabbit aorta endothelial cells (RAEC) non-tumor cell line proliferation displayed inhibition of 8.0%–22.0%. On the other hand, nanogel improved Chinese hamster ovary (CHO) and monocyte macrophage cell (RAW) non-tumor cell line proliferation in the same concentration range. The antiproliferative effect against tumor cells was also confirmed using the BrdU test. Flow cytometric analysis revealed that the fucan nanogel inhibited 786 cell proliferation through caspase and caspase-independent mechanisms. In addition, SNFuc blocks 786 cell passages in the S and G2-M phases of the cell cycle.The present study was supported by CAPES, MCT, FAPERN/CNPq and CNPq, Brazil, as well as FCT, Portugal. N Dantas-Santos, J Almeida-Lima, AAJ Vidal, HAO Rocha are grateful to the CNPq and CAPES for their fellowship support. This research was submitted to the Graduate Program in Health Sciences at the Federal University of Rio Grande do Norte as part of the D.Sc. thesis of ND-S
Evaluation of Anti-Nociceptive and Anti-Inflammatory Activities of a Heterofucan from Dictyota menstrualis
Fucan is a term that defines a family of homo-and hetero-polysaccharides containing sulfated L-fucose in its structure. in this work, a heterofucan (F2.0v) from the seaweed, Dictyota menstrualis, was evaluated as an antinociceptive and anti-inflammatory agent. F2.0v (20.0 mg/kg) inhibits 100% of leukocyte migration into the peritoneal cavity after chemical stimulation. However, F2.0v does not alter the expression of interleukin-1 beta (IL-1 beta) and interleukin-6 (IL-6), as well as tumor necrosis factor alpha (TNF-alpha). F2.0v (20.0 mg/kg) has peripheral antinociceptive activity with potency similar to dipyrone. On the other hand, it had no effect on pain response on the hot plate test. Confocal microscopy analysis and flow cytometry showed that F2.0v binds to the surface of leucocytes, which leads us to suggest that the mechanism of action of anti-inflammatory and antinociceptive F2.0v is related to its ability to inhibit the migration of leukocytes to the site of tissue injury. in summary, the data show that F2.0v compound has great potential as an antinociceptive and anti-inflammatory, and future studies will be performed to further characterize the mechanism of action of F2.0v.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundacao de Apoio a Pesquisa do Estado do Rio Grande do Norte-FAPERNCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Ministerio de Ciencia, Tecnologia e Inovacao-MCTIFed Univ Rio Grande Norte UFRN, Dept Biochem, Lab Biotechnol Nat Polymers BIOPOL, BR-59078970 Natal, RN, BrazilFed Univ Rio Grande Norte UFRN, Grad Program Hlth Sci, BR-59078970 Natal, RN, BrazilFed Univ São Paulo UNIFESP, Dept Biochem, BR-04044020 São Paulo, BrazilFed Univ São Paulo UNIFESP, Dept Biochem, BR-04044020 São Paulo, BrazilWeb of Scienc
Silver Nanoparticles Containing Fucoidan Synthesized by Green Method Have Anti-Trypanosoma cruzi Activity
Funding Information: Funding: This research was funded by the Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq (n◦ 408369/2016-7), Coordenação de Aperfeiçoamento Pessoal de Nível Superior (CAPES), Programa Ciências do Mar (AUXPE-CIMAR-1956/2014), and Programa Nacional de Cooperação Acadêmica (CAPES/PROCAD). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.The brown seaweed Spatoglossum schröederi synthesizes three bioactive fucoidans, the most abundant of which is fucan A. This fucoidan was extracted and its identity was confirmed by chemical analysis, Fourier-transform infrared spectroscopy (FTIR), and agarose gel electrophoresis. Thereafter, silver nanoparticles containing fucan A (AgFuc) were produced using an environmentally friendly synthesis method. AgFuc synthesis was analyzed via UV–vis spectroscopy and FTIR, which confirmed the presence of both silver and fucan A in the AgFuc product. Dynamic light scattering (DLS), X-ray diffraction, scanning electron microscopy, and atomic force microscopy revealed that the AgFuc particles were ~180.0 nm in size and spherical in shape. DLS further demonstrated that AgFuc was stable for five months. Coupled plasma optical emission spectrometry showed that the AgFuc particles contained 5% silver and 95% sugar. AgFuc was shown to be more effective in inhibiting the ability of parasites to reduce MTT than fucan A or silver, regardless of treatment time. In addition, AgFuc induced the death of ~60% of parasites by necrosis and ~17% by apoptosis. Therefore, AgFuc induces damage to the parasites’ mitochondria, which suggests that it is an anti-Trypanosoma cruzi agent. This is the first study to analyze silver nanoparticles containing fucan as an anti-Trypanosoma cruzi agent. Our data indicate that AgFuc nanoparticles have potential therapeutic applications, which should be determined via preclinical in vitro and in vivo studies.publishe
Insights of antiparasitic activity of sodium diethyldithiocarbamate against different strains of Trypanosoma cruzi
Funding Information: This research was funded by Global Health and Tropical Medicine: Grant number IHMT-UID/multi/04413/2013 and Grant number PTDC/CVT-CVT/28908/2017, FCT-Portugal. Funding Information: We would like to thank Prof. João Aristeu da Rosa and Dr. Aline Rimodi Rimeiro at UNESP (Universidade Estadual de São Paulo) Araraquara (Brazil) for offering four different strains of T. cruzi. JWFO, CJGM, and BAC thanks to the financial support (PhD and Post-doctoral fellowships) provided by Capes/Brazil; MSS and HAOR thanks to CNPq/Brazil for the Research Grant (Bolsa de Produtividade). We also would like to thank the Department of Materials Engineering at UFRN for allowing the use of their scanning electron microscope, and the Department of Biochemistry at UFRN for allowing the use of their Flow Cytometer. We are also grateful to Paulo Fanado for editing this manuscript. Publisher Copyright: © 2021, The Author(s).Chagas disease is caused by Trypanosoma cruzi and affects thousands of people. Drugs currently used in therapy are toxic and have therapeutic limitations. In addition, the genetic diversity of T. cruzi represents an important variable and challenge in treatment. Sodium diethyldithiocarbamate (DETC) is a compound with pharmacological versatility acting as metal chelators and ROS generation. Thus, the objective was to characterize the antiparasitic action of DETC against different strains and forms of T. cruzi and their mechanism. The different strains of T. cruzi were grown in LIT medium. To evaluate the antiparasitic activity of DETC, epimastigote and trypomastigote forms of T. cruzi were used by resazurin reduction methods and by counting. Different response patterns were obtained between the strains and an IC50 of DETC ranging from 9.44 ± 3,181 to 60.49 ± 7.62 µM. Cell cytotoxicity against 3T3 and RAW cell lines and evaluated by MTT, demonstrated that DETC in high concentration (2222.00 µM) presents low toxicity. Yet, DETC causes mitochondrial damage in T. cruzi, as well as disruption in parasite membrane. DETC has antiparasitic activity against different genotypes and forms of T. cruzi, therefore, representing a promising molecule as a drug for the treatment of Chagas disease.publishersversionpublishe
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