RESUMO
Experimental studies have demonstrated the potential of probiotics to control visceral toxocariasis, which is a tissue parasitosis that is difficult to treat. This study evaluated the in vitro activity of probiotics and their supernatants on Toxocara canis larvae. The probiotics Lactobacillus rhamnosus (ATCC 7469), Lactobacillus paracasei (ATCC 335), Saccharomyces boulardii, Saccharomyces cerevisiae, and Bacillus cereus var. toyoi were tested in the following preparations: probiotic (P) 1 × 102 to 1 × 109 colony-forming units (CFUs), inactivated probiotic (IP) 1 × 102 to 1 × 109 CFUs, supernatant probiotic (SUpP), and inactivated probiotic supernatant (SupIP). The probiotics and their respective supernatants were separately incubated with 100 T. canis larvae per well using microculture plates with RPMI-1640 medium for 48 hr at 37 C and 5% CO2. The evaluation of the in vitro tests was based on the viability of T. canis larvae, through morphologic integrity, positive motility, and the absence of trypan blue stain. Only culture supernatants (SUpP and SUpIP) of Lactobacillus spp. resulted in 100% dead larvae, whereas S. boulardii showed larvicidal activity in T. canis >70%. The rest of the tests did not show larvicide activity. Therefore, it is important to investigate the supernatant effects of Lactobacillus spp. and S. boulardii in vivo on T. canis visceral infections, their mechanisms of action, and major metabolites involved.
Assuntos
Canidae , Probióticos , Saccharomyces boulardii , Toxocara canis , Toxocaríase , Animais , Lactobacillus , Toxocaríase/prevenção & controle , LarvaRESUMO
Abstract Introduction Day care centers play an important social role in children's early education and development. The objective of this study was to investigate the frequency of intestinal parasitic infections and infection with Toxocara spp. in children from a day care center in the city of Rio Grande, Rio Grande do Sul, Brazil. Methods: The study was conducted using fecal samples from 50 children, ages three to six years, using Ritchie, Faust, Rugai, and Kinyoun's techniques. A closed and structured epidemiological questionnaire was used to collect data from the parents/guardians of the children. Serological studies for detection of antibodies to Toxocara spp. by immunoenzymatic assays using Toxocara excretion and secretion antigen (TES) were conducted on sera collected from 41 children. Results: The frequency of enteroparasites was 18%, with 43.9% of the children testing seropositive for Toxocara spp. Low family income and low literacy levels of parents/guardians were common factors between the families of the parasite-positive children. For the children who tested positive for Toxocara spp., most of the parents/guardians reported using only water for sanitizing raw vegetables and fruits. Conclusions: The high seropositivity rates for Toxocara spp. indicate that children were exposed to this parasite, and it is important to reduce the risk of infection. In addition, the seropositivity for enteroparasites and the interviews with the parents/guardians indicate the need to educate the studied population regarding the modes of intestinal parasite transmission and the prophylactic measures needed to prevent their dissemination.
Resumo Introdução As creches desempenham um importante papel social na educação e desenvolvimento inicial das crianças. O objetivo deste estudo foi investigar a frequência de infecções parasitárias intestinais, além de infecção por Toxocara spp. em crianças de uma creche na cidade do Rio Grande, Rio Grande do Sul, Brasil. Métodos: Para o estudo, foram coletadas amostras fecais de 50 crianças de três a seis anos, analisadas pelas técnicas de Ritchie, Faust, Rugai e Kinyoun, sendo aplicado um questionário epidemiológico fechado e estruturado aos pais/responsáveis das crianças. Também foi realizada uma pesquisa sorológica de anticorpos para Toxocara spp. em 41 crianças, pelo ensaio imunoenzimático, associado ao antígeno de excreção e secreção (ES), com soros pré-adsorvidos com antígeno somático de Ascaris lumbricoides. Resultados: A frequência de enteroparasitos foi de 18%, enquanto que 43.9% das crianças foram soropositivas para Toxocara spp.. Baixa renda familiar e baixo nível de alfabetização dos pais/responsáveis foram fatores comuns entre as famílias das crianças parasitadas. A maioria dos pais ou responsáveis das crianças, com diagnóstico positivo para enteroparasitos ou para Toxocara spp., relatou utilizar apenas água para a higienização de verduras e frutas. Conclusões: As altas taxas de soropositividade para Toxocara spp. indicam que as crianças foram expostas a esse parasito, sendo importante minimizar o risco de infecção. Além disso, a positividade de 18% para enteroparasitos e os dados obtidos com as entrevistas realizadas com os pais ou responsáveis demonstram a necessidade da realização de trabalhos com a população estudada que visem a divulgação sobre as parasitoses intestinais, especialmente sobre medidas profiláticas especificas.
Assuntos
Humanos , Animais , Pré-Escolar , Criança , Toxocara , Toxocaríase , Brasil , Anticorpos Anti-Helmínticos , Estudos Soroepidemiológicos , Hospital DiaRESUMO
INTRODUCTION: Day care centers play an important social role in children's early education and development. The objective of this study was to investigate the frequency of intestinal parasitic infections and infection with Toxocara spp. in children from a day care center in the city of Rio Grande, Rio Grande do Sul, Brazil. Methods: The study was conducted using fecal samples from 50 children, ages three to six years, using Ritchie, Faust, Rugai, and Kinyoun's techniques. A closed and structured epidemiological questionnaire was used to collect data from the parents/guardians of the children. Serological studies for detection of antibodies to Toxocara spp. by immunoenzymatic assays using Toxocara excretion and secretion antigen (TES) were conducted on sera collected from 41 children. Results: The frequency of enteroparasites was 18%, with 43.9% of the children testing seropositive for Toxocara spp. Low family income and low literacy levels of parents/guardians were common factors between the families of the parasite-positive children. For the children who tested positive for Toxocara spp., most of the parents/guardians reported using only water for sanitizing raw vegetables and fruits. Conclusions: The high seropositivity rates for Toxocara spp. indicate that children were exposed to this parasite, and it is important to reduce the risk of infection. In addition, the seropositivity for enteroparasites and the interviews with the parents/guardians indicate the need to educate the studied population regarding the modes of intestinal parasite transmission and the prophylactic measures needed to prevent their dissemination.
Assuntos
Toxocara , Toxocaríase , Animais , Anticorpos Anti-Helmínticos , Brasil , Criança , Pré-Escolar , Hospital Dia , Humanos , Estudos SoroepidemiológicosRESUMO
Abstract Introduction Day care centers play an important social role in childrens early education and development. The objective of this study was to investigate the frequency of intestinal parasitic infections and infection with Toxocara spp. in children from a day care center in the city of Rio Grande, Rio Grande do Sul, Brazil. Methods: The study was conducted using fecal samples from 50 children, ages three to six years, using Ritchie, Faust, Rugai, and Kinyouns techniques. A closed and structured epidemiological questionnaire was used to collect data from the parents/guardians of the children. Serological studies for detection of antibodies to Toxocara spp. by immunoenzymatic assays using Toxocara excretion and secretion antigen (TES) were conducted on sera collected from 41 children. Results: The frequency of enteroparasites was 18%, with 43.9% of the children testing seropositive for Toxocara spp. Low family income and low literacy levels of parents/guardians were common factors between the families of the parasite-positive children. For the children who tested positive for Toxocara spp., most of the parents/guardians reported using only water for sanitizing raw vegetables and fruits. Conclusions: The high seropositivity rates for Toxocara spp. indicate that children were exposed to this parasite, and it is important to reduce the risk of infection. In addition, the seropositivity for enteroparasites and the interviews with the parents/guardians indicate the need to educate the studied population regarding the modes of intestinal parasite transmission and the prophylactic measures needed to prevent their dissemination.
Resumo Introdução As creches desempenham um importante papel social na educação e desenvolvimento inicial das crianças. O objetivo deste estudo foi investigar a frequência de infecções parasitárias intestinais, além de infecção por Toxocara spp. em crianças de uma creche na cidade do Rio Grande, Rio Grande do Sul, Brasil. Métodos: Para o estudo, foram coletadas amostras fecais de 50 crianças de três a seis anos, analisadas pelas técnicas de Ritchie, Faust, Rugai e Kinyoun, sendo aplicado um questionário epidemiológico fechado e estruturado aos pais/responsáveis das crianças. Também foi realizada uma pesquisa sorológica de anticorpos para Toxocara spp. em 41 crianças, pelo ensaio imunoenzimático, associado ao antígeno de excreção e secreção (ES), com soros pré-adsorvidos com antígeno somático de Ascaris lumbricoides. Resultados: A frequência de enteroparasitos foi de 18%, enquanto que 43.9% das crianças foram soropositivas para Toxocara spp.. Baixa renda familiar e baixo nível de alfabetização dos pais/responsáveis foram fatores comuns entre as famílias das crianças parasitadas. A maioria dos pais ou responsáveis das crianças, com diagnóstico positivo para enteroparasitos ou para Toxocara spp., relatou utilizar apenas água para a higienização de verduras e frutas. Conclusões: As altas taxas de soropositividade para Toxocara spp. indicam que as crianças foram expostas a esse parasito, sendo importante minimizar o risco de infecção. Além disso, a positividade de 18% para enteroparasitos e os dados obtidos com as entrevistas realizadas com os pais ou responsáveis demonstram a necessidade da realização de trabalhos com a população estudada que visem a divulgação sobre as parasitoses intestinais, especialmente sobre medidas profiláticas especificas.
RESUMO
AIMS/HYPOTHESIS: Inhibitors of dipeptidyl peptidase-IV (DPP-IV), such as sitagliptin, increase glucagon-like peptide-1 (GLP-1) concentrations and are current treatment options for patients with type 2 diabetes mellitus. As patients with diabetes exhibit a high risk of developing severe atherosclerosis, we investigated the effect of sitagliptin on atherogenesis in Apoe (-/-) mice. METHODS: Apoe (-/-) mice were fed a high-fat diet and treated with either sitagliptin or placebo for 12 weeks. Plaque size and plaque composition were analysed using Oil Red O staining and immunohistochemistry. Furthermore, in vitro experiments with the modified Boyden chamber and with gelatine zymography were performed to analyse the effects of GLP-1 on isolated human monocyte migration and metalloproteinase-9 (MMP-9) release. RESULTS: Treatment of Apoe (-/-) mice with sitagliptin significantly reduced plaque macrophage infiltration (the aortic root and aortic arch both showing a 67% decrease; p < 0.05) and plaque MMP-9 levels (aortic root showing a 69% and aortic arch a 58% reduction; both p < 0.01) compared with controls. Moreover, sitagliptin significantly increased plaque collagen content more than twofold (aortic root showing an increase of 58% and aortic arch an increase of 73%; both p < 0.05) compared with controls but did not change overall lesion size (8.1 ± 3.5% vs 5.1 ± 2.5% for sitagliptin vs controls; p=NS). In vitro, pretreatment of isolated human monocytes with GLP-1 significantly decreased cell migration induced by both monocyte chemotactic protein-1 and by the protein known as regulated on activation, normal T cell expressed and secreted (RANTES) in a concentration-dependent manner. Furthermore, GLP-1 significantly decreased MMP-9 release from isolated human monocyte-derived macrophages. CONCLUSIONS/INTERPRETATION: Sitagliptin reduces plaque inflammation and increases plaque stability, potentially by GLP-1-mediated inhibition of chemokine-induced monocyte migration and macrophage MMP-9 release. The effects observed may provide potential mechanisms for how DPP-IV inhibitors could modulate vascular disease in high-risk patients with type 2 diabetes mellitus.
Assuntos
Arteriosclerose/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Inibidores da Dipeptidil Peptidase IV/farmacologia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Macrófagos/metabolismo , Pirazinas/farmacologia , Triazóis/farmacologia , Animais , Apolipoproteínas E/farmacologia , Arteriosclerose/tratamento farmacológico , Arteriosclerose/fisiopatologia , Peso Corporal , Células Cultivadas , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Peptídeo 1 Semelhante ao Glucagon/efeitos dos fármacos , Imuno-Histoquímica , Metabolismo dos Lipídeos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfato de SitagliptinaRESUMO
Previous data from our group demonstrated that C-peptide induces chemotaxis of CD4-positive lymphocytes in-vitro, mediated by activation of G-protein and PI 3-kinase gamma, but additional signalling pathways involved in this process remained unexplored. In the present study we further analyze intracellular signalling pathways which lead to C-peptide-induced CD4-positive lymphocyte migration. We provide evidence that C-peptide-induced chemotaxis of CD4-positive lymphocytes is critically dependent on activation of Src-kinase and RhoA, Rac-1 and Cdc42 GTPases. Furthermore, C-peptide stimulates phosphorylation of PAK, LIMK and cofilin downstream of Rac-1 and Cdc42, leading to cofilin inactivation and actin filament stabilization. In addition, C-peptide induces ROCK kinase activity and MLC phosphorylation downstream of RhoA, thereby stimulating myosin mediated cell contraction. In contrast, C-peptide does not activate ERK1/2, p38 or Akt in CD4-positive lymphocytes. Our data support an active role of C-peptide in CD4-positive lymphocyte chemotaxis and elucidate molecular mechanisms in C-peptide-induced cell migration.
Assuntos
Peptídeo C/farmacologia , Linfócitos T CD4-Positivos/fisiologia , Quimiotaxia de Leucócito/fisiologia , Transdução de Sinais/fisiologia , Citoesqueleto de Actina/metabolismo , Peptídeo C/fisiologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Células Cultivadas , Quimiotaxia de Leucócito/efeitos dos fármacos , Ativação Enzimática , Humanos , FosforilaçãoRESUMO
Visfatin is a recently described new adipokine that is considered to bind to the insulin receptor and induce insulin action via signal transduction pathways distinct from those of insulin. This study investigated whether circulating plasma visfatin levels may be influenced by PPARy activation, as shown for adiponectin and other adipokines. Samples from a prospective single-blinded placebo-controlled three-month intervention study with rosiglitazone were retrospectively analysed. The samples were derived from 39 patients with type 2 diabetes mellitus suffering from coronary artery disease as confirmed by angiography (rosiglitazone arm: 18 men, 1 woman, age (mean +/- STD): 65 +/- 9 years, disease duration: 4.8 +/- 4.0 years, HbA1c: 7.3 +/- 1.3%; Placebo: 19 men, 1 woman, age: 64 +/- 10 years, disease duration: 5.1 +/- 6.5 years, HbA1c: 7.5 +/- 1.5%). Laboratory measurements for lipids, adiponectin, and visfatin were performed with validated tests. The baseline values were comparable for all observation markers. After three months, a significant increase in the adiponectin concentrations could be observed only in the rosiglitazone group (from: 6.9 +/- 0.9 mg/l to 16.5 +/- 1.5 mg/l, (p < 0.001) vs placebo: 7.8 +/- 6.3 mg/l to 8.0 +/- 0.8 mg/l, (n.s.), p < 0.001 between the groups at endpoint). No changes were seen in both treatment arms for the other observation parameters. In particular, no influence of rosiglitazone was seen on the visfatin concentrations (25.9 +/- 2.3 ng/ml to 25.8 +/- 1.9 ng/ml; Placbo: 26.9 +/- 5.4 ng/ml to 27.2 +/- 4.9 ng/ml, n.s.). Our investigation demonstrates that rosiglitazone has different effects on circulating concentrations of adiponectin and visfatin. Visfatin secretion is not regulated by PPARgamma and further research is required to investigate its role in insulin resistance.
Assuntos
Doença da Artéria Coronariana/sangue , Citocinas/sangue , Diabetes Mellitus Tipo 2/sangue , Hipoglicemiantes/farmacologia , Nicotinamida Fosforribosiltransferase/sangue , Tiazolidinedionas/farmacologia , Adiponectina/sangue , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PPAR gama/agonistas , PPAR gama/metabolismo , Estudos Retrospectivos , RosiglitazonaRESUMO
BACKGROUND: The release of matrix degrading enzymes such as matrix metalloproteinase 9 (MMP-9) from bronchial epithelial cells is critically involved in airway wall remodelling in chronic inflammatory processes of the respiratory system. MMP-9 expression is induced by inflammatory mediators such as tumour necrosis factor (TNF)-alpha, but to date nothing is known about the mechanisms of inhibition of MMP-9 expression in these cells. METHODS: A study was undertaken to examine whether activators of the nuclear transcription factor peroxisome proliferator activated receptor gamma (PPARgamma) might modulate MMP-9 expression in two different bronchial epithelial cell lines. RESULTS: PPARgamma was expressed and was functionally active in NL20 and BEAS cells. Activation of PPARgamma by rosiglitazone or pioglitazone significantly reduced TNF-alpha and PMA induced MMP-9 gelatinolytic activity in a concentration dependent manner in both cell lines, but did not alter the expression of tissue inhibitor of MMPs type 1 (TIMP-1), the local inhibitor of MMP-9. Northern blot analysis revealed a decrease in MMP-9 mRNA expression following treatment with PPARgamma which resulted from the inhibition of NF-kappaB activation in these cells, as determined by transient transfection assays and electromobility shift assays. CONCLUSION: Activation of PPARgamma in human bronchial epithelial cells limits the expression of matrix degrading MMP-9. This might have therapeutic applications in chronic inflammatory processes of the respiratory system.
Assuntos
Brônquios/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Tiazolidinedionas , Fatores de Transcrição/metabolismo , Northern Blotting , Bronquite/metabolismo , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Células Epiteliais/metabolismo , Humanos , Hipoglicemiantes/farmacologia , Inibidores de Metaloproteinases de Matriz , Pioglitazona , Mucosa Respiratória/metabolismo , Rosiglitazona , Tiazóis/farmacologia , Inibidor Tecidual de Metaloproteinase-1/metabolismoRESUMO
The hitherto controversial valence states of nickel and tin in the ternary chalcogenide Ni(3)Sn(2)S(2) (see structure) have been determined by photoelectron and Mössbauer spectroscopy ((61)Ni, (119)Sn). Results from band structure calculations confirmed that this shandite phase is a metal and that the approximate distribution of the valence electrons is (Ni(0))(3)(Sn(1)(II))(Sn(2)(II))(S(II-))(2).