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1.
Braz. j. biol ; 82: e230147, 2022. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153479

RESUMO

Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams (≤ 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.


Os metais e agroquímicos estão entre os principais contaminantes aquáticos, podendo desencadear estresse oxidativo em organismos expostos. O objetivo deste trabalho foi avaliar uma possível correlação entre o nível de biomarcadores de estresse oxidativo em Aegla (Crustacea, Anomura) com (i) o conjunto de metais presentes no sedimento e (ii) com os usos da terra, em três bacias hidrográficas distintas. O estudo foi realizado em riachos (≤ 2ª ordem) de bacias hidrográficas do Sul do Brasil (Bacias do Rio Suzana, do Rio Ligeirinho-Leãozinho e do Rio Dourado), as quais foram caracterizadas em função do percentual de usos da terra e do nível de Cu, Cr, Cd, Fe, Mn e Zn no sedimento. As enzimas Catalase (CAT) e Glutationa Redutase (GR), bem como o nível de peroxidação lipídica das membranas (TBARS), foram analisadas em fêmeas adultas. Uma análise de PCA mostrou que a distribuição de metais foi distinta entre as bacias. Cd, Cr e Fe no sedimento correlacionaram positivamente com a CAT e negativamente com TBARS e GR. Entretanto, a bacia do Dourado apresentou os menores níveis destes três metais e os maiores níveis de TBARS, o que pode ser justificado pelo predomínio da agricultura nesta bacia, já que o TBARS correlacionou positivamente com o percentual de uso agrícola. Nesta bacia, a atividade da GR foi mais alta do que nas outras, indicando uma resposta compensatória em relação a inibição da CAT. As bacias do rio Suzana e rio Ligeirinho-Leãozinho apresentaram valores menores de TBARS, o que pode decorrer da indução da CAT em função dos metais acumulados no sedimento. Em síntese, este trabalho indica que nas bacias com maior concentração de metais tóxicos ocorre uma resposta adaptativa de indução da CAT, o que reduz os níveis de TBARS em Aegla. Por outro lado, na bacia com menor contaminação metálica os níveis de TBARS foram primariamente influenciados pelo uso agrícola.


Assuntos
Animais , Feminino , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Metais Pesados/análise , Anomuros , Brasil , Biomarcadores/metabolismo , Monitoramento Ambiental , Estresse Oxidativo , Rios , Agricultura
2.
Braz. j. biol ; 82: 1-9, 2022. map, tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468415

RESUMO

Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams (≤ 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.


Os metais e agroquímicos estão entre os principais contaminantes aquáticos, podendo desencadear estresse oxidativo em organismos expostos. O objetivo deste trabalho foi avaliar uma possível correlação entre o nível de biomarcadores de estresse oxidativo em Aegla (Crustacea, Anomura) com (i) o conjunto de metais presentes no sedimento e (ii) com os usos da terra, em três bacias hidrográficas distintas. O estudo foi realizado em riachos(≤ 2ª ordem) de bacias hidrográficas do Sul do Brasil (Bacias do Rio Suzana, do Rio Ligeirinho-Leãozinho e do Rio Dourado), as quais foram caracterizadas em função do percentual de usos da terra e do nível de Cu, Cr, Cd, Fe, Mn e Zn no sedimento. As enzimas Catalase (CAT) e Glutationa Redutase (GR), bem como o nível de peroxidação lipídicadas membranas (TBARS), foram analisadas em fêmeas adultas. Uma análise de PCA mostrou que a distribuição de metais foi distinta entre as bacias. Cd, Cr e Fe no sedimento correlacionaram positivamente com a CAT e negativamente com TBARS e GR. Entretanto, a bacia do Dourado apresentou os menores níveis destes três metais e os maiores níveis de TBARS, o que pode ser justificado pelo predomínio da agricultura nesta bacia, já que o TBARS correlacionou positivamente com o percentual de uso agrícola. Nesta bacia, a atividade da GR foi mais alta do que nas outras, indicando uma resposta compensatória em relação a inibição da CAT. As bacias do rio Suzana e rio Ligeirinho-Leãozinho apresentaram valores menores de TBARS, o que pode decorrer da indução da CAT em função dos metais acumulados no sedimento. Em síntese, este trabalho indica que nas bacias com maior concentração de metais tóxicos ocorre uma resposta adaptativa de indução da CAT, o que reduz os níveis de TBARS em Aegla. Por outro lado, na bacia com menor contaminação metálica os níveis de TBARS foram primariamente influenciados pelo uso agrícola.


Assuntos
Feminino , Animais , Catalase , Crustáceos , Estresse Oxidativo , Glutationa , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Zonas Agrícolas , Antioxidantes
3.
Braz. j. biol ; 822022.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1468602

RESUMO

Abstract Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams ( 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.


Resumo Os metais e agroquímicos estão entre os principais contaminantes aquáticos, podendo desencadear estresse oxidativo em organismos expostos. O objetivo deste trabalho foi avaliar uma possível correlação entre o nível de biomarcadores de estresse oxidativo em Aegla (Crustacea, Anomura) com (i) o conjunto de metais presentes no sedimento e (ii) com os usos da terra, em três bacias hidrográficas distintas. O estudo foi realizado em riachos ( 2ª ordem) de bacias hidrográficas do Sul do Brasil (Bacias do Rio Suzana, do Rio Ligeirinho-Leãozinho e do Rio Dourado), as quais foram caracterizadas em função do percentual de usos da terra e do nível de Cu, Cr, Cd, Fe, Mn e Zn no sedimento. As enzimas Catalase (CAT) e Glutationa Redutase (GR), bem como o nível de peroxidação lipídica das membranas (TBARS), foram analisadas em fêmeas adultas. Uma análise de PCA mostrou que a distribuição de metais foi distinta entre as bacias. Cd, Cr e Fe no sedimento correlacionaram positivamente com a CAT e negativamente com TBARS e GR. Entretanto, a bacia do Dourado apresentou os menores níveis destes três metais e os maiores níveis de TBARS, o que pode ser justificado pelo predomínio da agricultura nesta bacia, já que o TBARS correlacionou positivamente com o percentual de uso agrícola. Nesta bacia, a atividade da GR foi mais alta do que nas outras, indicando uma resposta compensatória em relação a inibição da CAT. As bacias do rio Suzana e rio Ligeirinho-Leãozinho apresentaram valores menores de TBARS, o que pode decorrer da indução da CAT em função dos metais acumulados no sedimento. Em síntese, este trabalho indica que nas bacias com maior concentração de metais tóxicos ocorre uma resposta adaptativa de indução da CAT, o que reduz os níveis de TBARS em Aegla. Por outro lado, na bacia com menor contaminação metálica os níveis de TBARS foram primariamente influenciados pelo uso agrícola.

4.
Braz J Biol ; 82: e230147, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729329

RESUMO

Metals and agrochemicals are among the main aquatic contaminants, being able to trigger oxidative stress in exposed organisms. The objective of this work was to evaluate the correlation between the level of oxidative stress biomarkers in Aegla crabs (Crustacea, Anomura) with (i) the set of metals present in the streams sediment and (ii) with land uses of three hydrographic basins. The study was carried out in streams (≤ 2nd order) of hydrographic basins in southern Brazil (Basins of Rio Suzana, Rio Ligeirinho-Leãozinho and Rio Dourado). In these streams were quantified the land uses and Cu, Cr, Cd, Fe, Mn and Zn concentrations in the sediment. The enzymes Catalase (CAT) and Glutathione Reductase (GR), as well as the level of membrane lipid peroxidation (TBARS), were analyzed in adult females. The PCA analysis showed that the distribution of metals was different between the basins. Cd, Cr and Fe were correlated positively with CAT and negatively with TBARS and GR. The Dourado basin had the lowest concentrations of these three metals and the highest levels of TBARS. However, in Dourado basin there is predominance of agriculture land use, and TBARS was positively correlated with agricultural land use. Besides in Dourado basin, GR activity was higher than in the others basins, indicating a compensatory response in relation to CAT inhibition. The basins of Suzana and Ligeirinho-Leãozinho rivers had lower TBARS values, which may be due to the induction of CAT in response to metals accumulated in sediment. In summary, this work indicates that in the basins with a higher concentration of toxic metals there is an adaptive response of CAT induction, which reduces TBARS in Aegla. On the other hand, in the basin with lower metallic contamination, TBARS occurrence was primarily influenced by agricultural land use.


Assuntos
Anomuros , Metais Pesados , Poluentes Químicos da Água , Agricultura , Animais , Biomarcadores/metabolismo , Brasil , Monitoramento Ambiental , Feminino , Metais Pesados/análise , Estresse Oxidativo , Rios , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
5.
Toxicol In Vitro ; 65: 104771, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31935486

RESUMO

Schistosomiasis is one of the most significant neglected tropical diseases, affecting around 260 million people worldwide, and Praziquantel is currently the only available drug for the treatment of infected persons. Thus, the search for new schistosomicidal compounds is urgent. The objective of this study was to investigate of the schistosomicidal effect of barbatic acid, a lichen metabolite, on adult worms of Schistosoma mansoni. The in vitro schistosomicidal effect was evaluated through the assessment of motility and mortality, cellular viability of the worms and ultrastructural analysis through scanning electron microscopy. To evaluate the cytotoxicity of barbatic acid, a cell viability assay was performed with human peripheral blood mononuclear cells. Barbatic acid showed a schistosomicidal effect after 3 h of exposure. At the end of 24 h the concentrations of 50-200 µM presented lethality on the worms. Motility changes were observed at sublethal concentrations. The IC50 obtained by the cell viability assay for S. mansoni was 99.43 µM. Extensive damage to the worm's tegument was observed from 25 µM. No cytotoxicity was observed on human peripheral blood mononuclear cells. This report provides data showing the schistosomicidal effect of barbatic acid on S. mansoni, causing death, motility changes and ultrastructural damage to worms. In addition, barbatic acid was shown to be non-toxic to human peripheral blood mononuclear cells at concentrations that are effective against S. mansoni.


Assuntos
Ascomicetos/química , Ácidos Ftálicos/toxicidade , Schistosoma mansoni/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Líquens/química , Microscopia Eletrônica de Varredura , Schistosoma mansoni/ultraestrutura
6.
Data Brief ; 19: 1393-1397, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30225292

RESUMO

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. Divaricatic acid showed high toxicity against both adult snails (5.5 µg/mL) and embryos (20 µg/mL after 6 h of exposure). Similar activity was observed in S. mansoni cercariae after only a short exposure time. The divaricatic acid proved to be a promising substance for the control of the snail B. glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen.

7.
Acta Trop ; 178: 97-102, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29097241

RESUMO

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. In addition, the environmental toxicity of divaricatic acid was assessed by bioassay using the microcrustacean Artemia salina. Divaricatic acid showed high toxicity against both adult snails (5µg/mL) and embryos (20µg/mL after 6h of exposure). Similar activity was observed in Schistosoma mansoni cercariae after only a short exposure time (10µg/mL after 30min of exposure). The divaricatic acid did not show toxicity in the acute test using Artemia salina at concentrations equal to or below 200µg/mL. The divaricatic acid proved to be a promising substance for the elimination of the snail Biomphalaria glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen, while being non-toxic to the Artemia salina at the same concentrations. This is the first experimental observation of the molluscicidal and cercaricide activity of divaricatic acid.


Assuntos
Antiparasitários/farmacologia , Biomphalaria/efeitos dos fármacos , Depsídeos/farmacologia , Moluscocidas/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Animais , Artemia , Cercárias/efeitos dos fármacos
8.
J Tissue Eng Regen Med ; 12(3): e1785-e1795, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29024519

RESUMO

Human bone marrow-derived mesenchymal stem/stromal cells (hMSCs) are considered promising therapeutic agents in the field of cell therapy and regenerative medicine, mainly due to their relative facility to be isolated, multi-differentiation potential, and immunomodulatory role. However, their application in clinics requires a crucial step of in vitro expansion. Most of the protocols for hMSCs in vitro culture use foetal bovine serum as medium supplement that, being from animal origin, presents several safety concerns and may initiate xenogeneic immune responses after cells transplantation. This work reports the optimization of a pharmaceutical-grade xeno-free strategy for hMSCs in vitro expansion based on the supplementation of basal medium with a pharmaceutical-grade human plasma-derived supplement for cell culture (SCC) and 2 human growth factors (bFGF and TGFß1), plus a coating of human plasma fibronectin (Fn). After 4 weeks in culture, this strategy improves hMSCs expansion yield about 4.3-fold in comparison with foetal bovine serum supplementation and 4.5-fold compared with a commercially available xeno-free medium. hMSCs expanded in SCC-based formulation maintained their phenotype and differentiation capacity into osteogenic, adipogenic, and chondrogenic lineages, without alterations in cell karyotype. Overall, the SCC-based medium appears to be an excellent alternative for the xeno-free expansion of hMSCs as therapeutic agents for clinical applications.


Assuntos
Meios de Cultura/farmacologia , Células-Tronco Mesenquimais/citologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células CHO , Diferenciação Celular/efeitos dos fármacos , Linhagem da Célula/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Fibronectinas/farmacologia , Humanos , Imunofenotipagem , Cariótipo , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Adulto Jovem
9.
Stem Cells Int ; 2017: 6597815, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29158740

RESUMO

Human mesenchymal stem/stromal cells (hMSCs) have generated great interest in regenerative medicine mainly due to their multidifferentiation potential and immunomodulatory role. Although hMSC can be obtained from different tissues, the number of available cells is always low for clinical applications, thus requiring in vitro expansion. Most of the current protocols for hMSC expansion make use of fetal bovine serum (FBS) as a nutrient-rich supplement. However, regulatory guidelines encourage novel xeno-free alternatives to define safer and standardized protocols for hMSC expansion that preserve their intrinsic therapeutic potential. Since hMSCs are adherent cells, the attachment surface and cell-adhesive components also play a crucial role on their successful expansion. This review focuses on the advantages/disadvantages of FBS-free media and surfaces/coatings that avoid the use of animal serum, overcoming ethical issues and improving the expansion of hMSC for clinical applications in a safe and reproducible way.

10.
Biomed Res Int ; 2017: 5948936, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28337452

RESUMO

Studies about toxicological potential of usnic acid are limited. This way, the vast majority of data available in the literature are related only to biological activities. This is the first study that aimed to evaluate the oral toxicity of usnic acid during the period of organogenesis. Females rats were distributed in the control groups, treated I and II, at doses of 15 and 25 mg/kg, administered by gavage during the 6° to 15° days of pregnancy. After 20 days the fetuses were removed and analyzed. A reduction in weight gain during pregnancy, increased resorption, reduction in the number of viable fetuses, and their body weight were observed. Morphological changes in the litter were visualized as exposure of the eye and atrophy of the limbs at the dose of 25 mg/kg. Histological analysis of the liver of the fetus showed reduction in the number of megakaryocytes between experimental groups and increase in the number of hepatocytes in a dose of 25 mg/kg. The experimental model used in this study reveals teratogenic effect of usnic acid in the period of organogenesis. Since this achievement, the importance of evaluating the toxic effects of natural substances is imperative, in order to elucidate the care in their indication as drug.


Assuntos
Benzofuranos/administração & dosagem , Organogênese/efeitos dos fármacos , Teratogênese/efeitos dos fármacos , Animais , Ascomicetos/química , Benzofuranos/química , Peso Corporal/efeitos dos fármacos , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Feto/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Ratos
11.
ACS Appl Mater Interfaces ; 9(9): 7979-7989, 2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28165702

RESUMO

Infection and thrombus formation are still the biggest challenges for the success of blood contact medical devices. This work aims the development of an antimicrobial and hemocompatible biomaterial coating through which selective binding of albumin (passivant protein) from the bloodstream is promoted and, thus, adsorption of other proteins responsible for bacterial adhesion and thrombus formation can be prevented. Polyurethane (PU) films were coated with hyaluronic acid, an antifouling agent, that was previously modified with thiol groups (HA-SH), using polydopamine as the binding agent. Octadecyl acrylate (C18) was used to attract albumin since it resembles the circulating free fatty acids and albumin is a fatty acid transporter. Thiol-ene "click chemistry" was explored for C18 immobilization on HA-SH through a covalent bond between the thiol groups from the HA and the alkene groups from the C18 chains. Surfaces were prepared with different C18 concentrations (0, 5, 10, and 20%) and successful immobilization was demonstrated by scanning electron microscopy (SEM), water contact angle determinations, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The ability of surfaces to bind albumin selectively was determined by quartz crystal microbalance with dissipation (QCM-D). Albumin adsorption increased in response to the hydrophobic nature of the surfaces, which augmented with C18 saturation. HA-SH coating reduced albumin adsorption to PU. C18 immobilized onto HA-SH at 5% promoted selective binding of albumin, decreased Staphylococcus aureus adhesion and prevented platelet adhesion and activation to PU in the presence of human plasma. C18/HA-SH coating was established as an innovative and promising strategy to improve the antimicrobial properties and hemocompatibility of any blood contact medical device.


Assuntos
Propriedades de Superfície , Adsorção , Anti-Infecciosos , Química Click , Humanos , Ácido Hialurônico , Poliuretanos , Compostos de Sulfidrila
12.
J R Soc Interface ; 11(101): 20141040, 2014 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-25320070

RESUMO

The strength of binding between the Helicobacter pylori blood group antigen-binding adhesin (BabA) and its cognate glycan receptor, the Lewis b blood group antigen (Le(b)), was measured by means of atomic force microscopy. High-resolution measurements of rupture forces between single receptor-ligand pairs were performed between the purified BabA and immobilized Le(b) structures on self-assembled monolayers. Dynamic force spectroscopy revealed two similar but statistically different bond populations. These findings suggest that the BabA may form different adhesive attachments to the gastric mucosa in ways that enhance the efficiency and stability of bacterial adhesion.


Assuntos
Adesinas Bacterianas/metabolismo , Aderência Bacteriana/fisiologia , Helicobacter pylori/metabolismo , Oligossacarídeos/metabolismo , Adesinas Bacterianas/química , Mucosa Gástrica/química , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiologia , Helicobacter pylori/ultraestrutura , Humanos , Antígenos do Grupo Sanguíneo de Lewis , Microscopia de Força Atômica , Oligossacarídeos/química
13.
Acta Biomater ; 9(11): 8885-93, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23831721

RESUMO

Helicobacter pylori colonizes the gastric mucosa of half of the worlds population and persistent infection is related with an increase in the risk of gastric cancer. Adhesion of H. pylori to the gastric epithelium, which is essential for infection, is mediated by bacterial adhesin proteins that recognize specific glycan structures (Gly-R) expressed in the gastric mucosa. The blood group antigen binding adhesin (BabA) recognizes difucosylated antigens such as Lewis B (Leb), while the sialic acid binding adhesin (SabA) recognizes sialylated glycoproteins and glycolipids, such as sialyl-Lewis x (sLex). This work aimed to investigate whether these Gly-Rs (Leb and sLex) can attract and specifically bind H. pylori after immobilization on synthetic surfaces (self-assembled monolayers (SAMs) of alkanethiols on gold). Functional bacterial adhesion assays for (Gly-R)-SAMs were performed using H. pylori strains with different adhesin protein profiles. The results demonstrate that H. pylori binding to surfaces occurs via interaction between its adhesins and cognate (Gly-R)-SAMs and bound H. pylori maintains its characteristic rod-shaped morphology only during conditions of specific adhesin-glycan binding. These results offer new insights into innovative strategies against H. pylori infection based on the scavenging of bacteria from the stomach using specific H. pylori chelating biomaterials.


Assuntos
Adesinas Bacterianas/metabolismo , Aderência Bacteriana , Bioengenharia , Helicobacter pylori/fisiologia , Polissacarídeos/metabolismo , Estômago/microbiologia , Adsorção , Avidina/metabolismo , Biotina/metabolismo , Glicoesfingolipídeos/metabolismo , Helicobacter pylori/citologia , Proteínas Imobilizadas/metabolismo , Cinética , Técnicas de Microbalança de Cristal de Quartzo , Propriedades de Superfície
14.
Acta Biomater ; 9(7): 7209-17, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23571000

RESUMO

Designing new biomaterials that can modulate the inflammatory response instead of attempting just to reduce it constitutes a paradigm change in regenerative medicine. This work aimed to investigate the capacity of an immunomodulatory biomaterial to enhance bone regeneration. For that purpose we incorporated a molecule with well-established pro-inflammatory and pro-healing roles, fibrinogen, in chitosan scaffolds. Two different incorporation strategies were tested, leading to concentrations of 0.54±0.10mg fibrinogen g(-1) scaffold immediately upon adsorption (Fg-Sol), and 0.34±0.04mg fibrinogen g(-1) scaffold after washing (Fg-Ads). These materials were implanted in a critical size bone defect in rats. At two months post-implantation the extent of bone regeneration was examined by histology and the systemic immune response triggered was evaluated by determining the percentages of myeloid cells, T and B lymphocytes in the draining lymph nodes. The results obtained indicate that the fibrinogen incorporation strategy conditioned the osteogenic capacity of biomaterials. Fg-Ads scaffolds led to more bone formation, and the presence of Fg stimulated angiogenesis. Furthermore, animals implanted with Fg-Ads scaffolds showed significant increases in the percentages of B lymphocytes and myeloid cells in the draining lymph nodes, while levels of T lymphocytes were not significantly different. Finally, a significant increase in TGF-ß1 was detected in the plasma of animals implanted with Fg-Ads. Taken together the results presented suggest a potential correlation between the elicited immune response and biomaterial osteogenic performance.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Regeneração Óssea/imunologia , Fibrinogênio/administração & dosagem , Fibrinogênio/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Síndrome de Resposta Inflamatória Sistêmica/prevenção & controle , Tecidos Suporte/efeitos adversos , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/imunologia , Adsorção , Animais , Regeneração Óssea/efeitos dos fármacos , Quitosana/química , Implantes de Medicamento/administração & dosagem , Desenho de Equipamento , Análise de Falha de Equipamento , Fibrinogênio/química , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/imunologia , Fatores Imunológicos , Masculino , Teste de Materiais , Ratos , Ratos Wistar , Estatística como Assunto , Resultado do Tratamento
15.
Rev. bras. plantas med ; 15(3): 415-422, 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-684159

RESUMO

Foram avaliados os efeitos antiinflamatório, antibacteriano e mutagênico do extrato aquoso das sementes de Amburana cearensis. A atividade antiinflamatória foi avaliada em modelo de edema de pata induzido por carragenina, utilizando o extrato em concentrações de 10 % e 20 % nos grupos experimentais; AAS 10 mg/kg (v.o) no grupo padrão e água destilada no grupo controle. A atividade antimicrobiana foi determinada através do método de diluição em Agar, utilizando concentrações de extrato de 10 %, 7,5 %, 5 %, 2,5 % e 1 % em cepas de Sthaphylococcus aureus ATCC 27853, Escherichia coli ATCC 25922 e Pseudomonas aeruginosas ATCC 25923) e a atividade mutagênica foi determinada pelo teste de Allium cepa, utilizando extrato em concentrações de 0,02 mg/mL, 0,1 mg/mL e 0,5 mg/mL. O extrato aquoso das sementes de Amburana cearensis nas concentrações de 10 % e 20 % apresentou efeito antiedematogênico, estatisticamente significativo a partir de duas horas após administração do flogógeno, e tal efeito persistiu até 24 horas após a indução da resposta inflamatória. Quanto à atividade antibacteriana, o extrato não apresentou ação contra as cepas bacterianas de Sthaphylococcus aureus, Escherichia coli e Pseudomonas aeruginosas nas concentrações testadas. A análise dos resultados do teste de Allium cepa evidenciou ação tóxica (em concentração de 0,5 mg/mL) e mutagênica (micronúcleo 0,1 mg/mL e aberrações cromossômicas 0,1 mg/mL e 0,5 mg/mL) do extrato de Amburana cearensis em células meristemáticas de Allium cepa. Tais resultados sugerem potencial aplicação terapêutica no tratamento da inflamação. Contudo, também demonstram a necessidade de estudar para comprovar a segurança na utilização dessa espécie.


The anti-inflammatory, antibacterial and mutagenic effects of the aqueous extract of Amburana cearensis seeds were evaluated. The anti-inflammatory activity was evaluated by a paw edema model induced by carrageenan, using the extract at 10 % and 20 % concentrations in the experimental groups: AAS 10 mg/kg (orally administrated) in the standard group and distilled water in the control group. The antimicrobial activity was determined by the agar dilution method, using extract concentrations of 10 %, 7.5 %, 5 %, 2.5 % and 1% in strains of Staphylococcus aureus ATCC 27853, Escherichia coli ATCC 25922 and Pseudomonas aeruginosas ATCC 25923), and the mutagenic activity was determined by the Allium cepa test using extract concentrations of 0,02 mg/mL, 0,1 mg/mL and 0,5 mg/mL. The aqueous extract of Amburana cearensis seeds at 10 % and 20 % concentrations had an statistically significant antiedematogenic effect two hours after administering the flogogen, and this effect persisted for up to 24 hours after inducing the inflammatory response. Regarding the antibacterial activity, the extract showed no action against the bacterial strains of Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosas at the concentrations tested. The results of the Allium cepa test showed the toxic (at a concentration of 0,5 mg/mL) and mutagenicity (0.1 mg/mL micronucleus and 0.1 mg/mL and 0.5 mg/mL chromosomal aberrations) actions of the Amburana cearensis extract on meristematic cells of Allium cepa. These results suggest potential therapeutic applications to treat inflammations. However, they also show the need for further studies to demonstrate the safe use of this species.


Assuntos
Animais , Feminino , Ratos , Bursera/classificação , Anti-Infecciosos/análise , Anti-Inflamatórios/análise , Mutagênicos/análise , Sementes , Extratos Vegetais/uso terapêutico , Carragenina , Edema
16.
Acta Biomater ; 8(11): 4101-10, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22846590

RESUMO

Thrombus formation, due to thrombin generation, is a major problem affecting blood-contacting medical devices. This work aimed to develop a new strategy to improve the hemocompatibility of such devices by the immobilization of a naturally occurring thrombin inhibitor into a nanostructured surface. Boophilin, a direct thrombin inhibitor from the cattle tick Rhipicephalus microplus, was produced as a recombinant protein in Pichia pastoris. Boophilin was biotinylated and immobilized on biotin-terminated self-assembled monolayers (SAM) via neutravidin. In order to maintain its proteinase inhibitory capacity after surface immobilization, boophilin was biotinylated after the formation of a boophilin-thrombin complex to minimize the biotinylation of the residues involved in thrombin-boophilin interaction. The extent of boophilin biotinylation was determined using matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. Boophilin immobilization and thrombin adsorption were quantified using quartz crystal microbalance with dissipation. Thrombin competitive adsorption from human serum was assessed using ¹²5I-thrombin. Thrombin inhibition and plasma clotting time were determined using spectrophotometric techniques. Boophilin-coated SAM were able to promote thrombin adsorption in a selective way, inhibiting most of its activity and delaying plasma coagulation in comparison with boophilin-free surfaces, demonstrating boophilin's potential to improve the hemocompatibility of biomaterials used in the production of blood-contacting devices.


Assuntos
Antitrombinas/farmacologia , Materiais Biocompatíveis/farmacologia , Bioengenharia , Teste de Materiais , Trombina/farmacologia , Adsorção/efeitos dos fármacos , Sequência de Aminoácidos , Animais , Antitrombinas/química , Antitrombinas/isolamento & purificação , Biotinilação/efeitos dos fármacos , Coagulação Sanguínea/efeitos dos fármacos , Bovinos , Ativação Enzimática/efeitos dos fármacos , Humanos , Hidrólise/efeitos dos fármacos , Proteínas Imobilizadas/metabolismo , Dados de Sequência Molecular , Peso Molecular , Proteínas Recombinantes/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Propriedades de Superfície , Trombina/química
17.
Eat Weight Disord ; 17(1): e29-35, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22751269

RESUMO

BACKGROUND: Orthorexia nervosa (ON) is described as an obsessive pathological behavior characterized by a strong preoccupation with healthy eating and the avoidance of foods or ingredients considered unhealthy by the subject. Although it is still not officially recognized as an eating disorder, previous studies have discussed its frequency in some groups and a fifteen-question test (ORTO-15) was developed elsewhere to assess ON behavior. OBJECTIVE: The present study aimed to evaluate ON behavior in a sample of Brazilian dietitians after testing the psychometric properties of the Portuguese version of ORTO-15. METHODS: A total of 392 dietitians answered an online version of the test. The answers were analyzed regarding ON tendency, according with the scoring grid proposed by its authors. Exploratory factor analysis was performed and internal consistency was assessed. RESULTS: It was found that three questions of the test presented loadings lower than 0.5. The 12 remaining question formed 3 factors with internal consistency of -0.51, 0.63 and 0.47. The answers of the participants to these questions revealed a tendency to orthorexic behavior, mainly regarding aspects such as: making food choices conditioned by worry about health status, evaluating food rather from nutritional quality than from its taste, believing that consuming healthy food may improve appearance, discrediting the influence of mood on eating behavior and banning food choices considered by them as eating transgressions. CONCLUSION: There is no evidence of the validity and reliability of the ORTO-15 with the initial psychometric evaluation performed. Further analyses are needed. Nevertheless, it was possible to observe a high frequency of orthorexic behavior among the studied Brazilian dietitians. However, additional studies are needed to completely understand dietitians behavior toward ON.


Assuntos
Dietética , Comportamento Alimentar/psicologia , Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Comportamento Obsessivo/diagnóstico , Adulto , Idoso , Brasil , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Psicometria/instrumentação , Reprodutibilidade dos Testes , Inquéritos e Questionários
18.
Arq. bras. med. vet. zootec ; 63(3): 768-772, June 2011. tab
Artigo em Português | LILACS | ID: lil-595600

RESUMO

Kartagener is syndrome is a rare disorder described in dogs determined by the triad situs inversus totalis, chronic sinusitis, and bronchial disease. The clinical signs of chronic respiratory and other less common presentations (such as hydrocephalus and subfertility) are due to a concomitant ciliary dysfunction. This article describes the clinical, radiographic, and computed tomography findings and treatment in a dog affected by Kartagener is syndrome since early months of life. This is the first case report of this syndrome in a domestic dog in Brazil and the only known scientific report in the English Cocker Spaniel.


Assuntos
Animais , Cães , Síndrome de Kartagener , Vísceras/anatomia & histologia , Broncopatias/veterinária , Tomografia/veterinária , Topografia/análise
19.
Transplant Proc ; 42(2): 461-4, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20304165

RESUMO

To study whether treatment with 5'-adenosine triphosphate (ATP), an agonist of P2 purine receptors, attenuated intestinal dysfunction caused by ischemia (I) and/or reperfusion (R), rabbits were treated with ATP (15 mgxkg(-1), intravenously) or saline solution (SS) 60 minutes before I by occlusion of the superior mesenteric artery and/or R (120 minutes). After I or I/R isolated 2-cm jejunal segments were mounted in an organ bath to study nerve-mediated contractions stimulated by electrical pulses or KCl using a digital recording system. Thin jejunal slices were stained (hematoxylin and eosin) for optical microscopy. Compared to a sham group, the jejunal contractions were similar to sham hosts among I + ATP, but reduced in I + SS, I/R + SS, and I/R + ATP groups. The jejunal-enteric nerves were damaged in I + SS, I/R + SS, and I/R + ATP, but not the I + ATP group. These results suggested that ATP attenuated intestinal dysfunction produced by I, but not that caused by R.


Assuntos
Trifosfato de Adenosina/farmacologia , Intestinos/irrigação sanguínea , Isquemia/fisiopatologia , Jejuno/irrigação sanguínea , Traumatismo por Reperfusão/fisiopatologia , Animais , Circulação Sanguínea/efeitos dos fármacos , Circulação Sanguínea/fisiologia , Isquemia/tratamento farmacológico , Jejuno/efeitos dos fármacos , Jejuno/inervação , Masculino , Artéria Mesentérica Superior/efeitos dos fármacos , Artéria Mesentérica Superior/fisiopatologia , Coelhos , Cloreto de Sódio/farmacologia
20.
J Biomed Mater Res A ; 93(1): 12-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19484768

RESUMO

The adhesion of human leukocytes to nanostructured surfaces with different chemical properties and the effect of protein adsorption were investigated. Self-assembled monolayers (SAMs) prepared with mixtures of methyl- and hydroxyl-terminated alkanethiols in different percentages on gold were used. The surfaces were pre-immersed in distinct protein solutions (human serum albumin, human fibrinogen, and autologous plasma). Adherent leukocytes were analyzed both by light and SEM. SAMs submitted to pre-immersion in plasma presented higher numbers of adherent leukocytes in the pure OH-terminated SAM, whereas methyl-terminated surfaces accounted for the lowest number of adherent cells. We observed a general increase in the number of adherent human leukocytes as the percentage of OH groups on the surface of the SAMs increased for all the pre-immersion conditions investigated. The number of adherent human leukocytes is highly influenced by the pre-immersion conditions used, and this observation is particularly relevant in the case of the methyl-terminated SAMs. The results obtained demonstrate that surface chemistry has a major influence in leukocyte adhesion to biomaterials, and that pre-immersion in protein solutions has a determinant effect in leukocyte adhesion.


Assuntos
Proteínas Sanguíneas/metabolismo , Radical Hidroxila/química , Leucócitos/citologia , Adsorção/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Ouro/farmacologia , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/ultraestrutura , Propriedades de Superfície/efeitos dos fármacos
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