ANÁLISIS DEL TIPO DE DAÑO CAUSADO POR Croton urucurana EM Candida albicans

Candida albicans é um fungo diploide, polimórfico, presente na microbiota normal humana, ora comensal ora oportunista, se em desequilíbrio com o ambiente do hospedeiro. Croton urucurana, ou “Sangra d´água”, tem aplicações medicinais largamente aplicadas pela medicina popular, mas que ainda requerem estudos quanto a sua eficácia e segurança. Diante disso, o objetivo deste trabalho foi analisar a ação gerada pelo extrato de  C. urucurana em C. albicans e sua potencial atividade citotóxica em células humanas. Para isso, foi obtido o extrato hidroalcoólico de C. urucurana, com rendimento de 5,24%. A partir do método colorimétrico com o emprego de resazurina em placa de microtitulação, que age nas mitocôndrias, obteve-se uma concentração inibitória mínima (CIM) do extrato de 375 mg/mL, a mesma encontrada na presença do ergosterol, um componente da membrana plasmática fúngica. Além disso, foi testado o crescimento do fungo na coexistência com sorbitol, um protetor osmótico, o que elevou a CIM para 1.500 mg/mL. A fim de avaliar a citotoxicidade do extrato em células humanas normais, utilizou-se células de fibroblastos pulmonares, cuja CIM foi de 375mg/mL. Enquanto resultados, constatou-se que o extrato hidroalcoólico de C. urucurana é danoso à atividade mitocondrial e à parede celular de C. albicans, contudo, sem deleção sobre a membrana celular. Mais ainda, apresenta-se citotóxico às células humanas nas mesmas concentrações que para as células fúngicas. Assim, o extrato de C. urucurana apresenta atividade antifúngica com baixa seletividade, sem segurança suficiente à utilização enquanto antifúngico.Candida albicans is a polymorphic diploid fungi found in normal human microbiota, at times commensal at times oportunistic. Croton urucurana, or ‘'Sangra d’água’’, has therapeutic applications used in medical treatments throughout common cultures, whilst require further developments of its use with efficiency and safety in human conditions. Thus, the current project aims to analyze the action tool of C. urucurana and its outcomes on C. albicans, as well as its cytotoxic activity in human cells. Thereunto, the hydroalcoholic extract of C. urucurana was obtained with an income of 5,24%. From using the colorimetric method with resazurin in a microtiter plate, which has mitocondrial effects, it was obtained a minimum inhibitory concentration (MIC) of 375 mg/mL of the extract, the same found in the presence of ergosterol, a component of the fungal plasmatic membrane. Furthermore, the growth of C. albicans in coexistence with additional sorbitol, an osmotic protector, was tested, raising the minimum inhibitory concentration to 1,500 mg/mL. In order to evaluate the cytotoxicity of C. urucurana, lung fibroblasts were used ensuing in an extract MIC of 375mg/dL. As results, it was found the extract can damage the fungal mitochondrial activity and the cell's wall, although with no deleterious effects on the cell's membrane. Moreover, with the same tested concentrations in fungal cells, it was established its human cells citotoxicity. Thereby, it was figured that C. urucurana has antifungal activity with low selectivity and so is not appliable to testing as a potential antifungal drug.Candida albicans é um fungo diploide, polimórfico, presente na microbiota normal humana, ora comensal ora oportunista, se em desequilíbrio com o ambiente do hospedeiro. Croton urucurana, ou “Sangra d´água”, tem aplicações medicinais largamente aplicadas pela medicina popular, mas que ainda requerem estudos quanto a sua eficácia e segurança. Diante disso, o objetivo deste trabalho foi analisar a ação gerada pelo extrato de  C. urucurana em C. albicans e sua potencial atividade citotóxica em células humanas. Para isso, foi obtido o extrato hidroalcoólico de C. urucurana, com rendimento de 5,24%. A partir do método colorimétrico com o emprego de resazurina em placa de microtitulação, que age nas mitocôndrias, obteve-se uma concentração inibitória mínima (CIM) do extrato de 375 mg/mL, a mesma encontrada na presença do ergosterol, um componente da membrana plasmática fúngica. Além disso, foi testado o crescimento do fungo na coexistência com sorbitol, um protetor osmótico, o que elevou a CIM para 1.500 mg/mL. A fim de avaliar a citotoxicidade do extrato em células humanas normais, utilizou-se células de fibroblastos pulmonares, cuja CIM foi de 375mg/mL. Enquanto resultados, constatou-se que o extrato hidroalcoólico de C. urucurana é danoso à atividade mitocondrial e à parede celular de C. albicans, contudo, sem deleção sobre a membrana celular. Mais ainda, apresenta-se citotóxico às células humanas nas mesmas concentrações que para as células fúngicas. Assim, o extrato de C. urucurana apresenta atividade antifúngica com baixa seletividade, sem segurança suficiente à utilização enquanto antifúngico.Candida albicans es un hongo diploide, polimórfico, presente en la microbiota humana normal, a veces comensal u oportunista, si está en desequilibrio con el entorno del huésped. Croton urucurana, o "Sangra d'água", tiene aplicaciones medicinales ampliamente aplicadas por la medicina popular, pero que aún requieren estudios en cuanto a su eficacia y seguridad. Por lo tanto, el objetivo de este trabajo fue analizar la acción generada por el extracto de C. urucurana en C. albicans y su potencial actividad citotóxica en células humanas. Para ello se obtuvo el extracto hidroalcohólico de C. urucurana, con un rendimiento del 5,24%. A partir del método colorimétrico con el uso de resazurina en placa de microtitulación, que actúa sobre las mitocondrias, se obtuvo una concentración inhibitoria mínima (CMI) del extracto de 375 mg/mL, la misma encontrada en presencia de ergosterol, componente de la membrana plasmática fúngica. Además, se probó el crecimiento del hongo en coexistencia con el sorbitol, un protector osmótico, lo que elevó la CMI a 1.500 mg/mL. Para evaluar la citotoxicidad del extracto en células humanas normales, utilizamos células de fibroblastos pulmonares, cuya CMI fue de 375 mg/ml. Como resultado, se encontró que el extracto hidroalcohólico de C. urucurana es perjudicial para la actividad mitocondrial y la pared celular de C. albicans, sin embargo, sin deleción en la membrana celular.

Stanniocalcin 2 contributes to aggressiveness and is a prognostic marker for oral squamous cell carcinoma

Stanniocalcin 2 (STC2), a glycoprotein that regulates calcium and phosphate homeostasis during mineral metabolism, appears to display multiple roles in tumorigenesis and cancer progression. This study aimed to access the prognostic value of STC2 in oral squamous cell carcinoma (OSCC) and its implications in oral tumorigenesis. STC2 expression was examined in 2 independent cohorts of OSCC tissues by immunohistochemistry. A loss-of-function strategy using shRNA targeting STC2 was employed to investigate STC2 in vitro effects on proliferation, apoptosis, migration, invasion, epithelial-mesenchymal transition (EMT) and possible activation of signaling pathways. Moreover, STC2 effects were assessed in vivo in a xenograft mouse cancer model. High expression of STC2 was significantly associated with poor disease-specific survival (HR: 2.67, 95% CI: 1.37-5.21, p = 0.001) and high rate of recurrence with a hazard ratio of 2.80 (95% CI: 1.07-5.71, p = 0.03). In vitro downregulation of STC2 expression in OSCC cells attenuated proliferation, migration and invasiveness while increased apoptotic rates. In addition, the STC2 downregulation controlled EMT phenotype of OSCC cells, with regulation on E-cadherin, vimentin, Snaill, Twist and Zeb2. The reactivation of STC2 was observed in the STC2 knockdown cells in the in vivo xenograft model, and no influence on tumor growth was observed. Modulation of STC2 expression levels did not alter consistently the phosphorylation status of CREB, ERK, JNK, p38, p70 S6K, STAT3, STAT5A/B and AKT. Our findings suggest that STC2 overexpression is an independent marker of OSCC outcome and may contribute to tumor progression via regulation of proliferation, survival and invasiveness of OSCC cells.Peer reviewe

Activation of Human CD11b+ B1 B-Cells by Trypanosoma cruzi-Derived Proteins Is Associated With Protective Immune Response in Human Chagas Disease

B-cells mediate humoral adaptive immune response via the production of antibodies and cytokines, and by inducing T-cell activation. These functions can be attributed to distinct B-cell subpopulations. Infection with Trypanosoma cruzi, the causative agent of Chagas disease, induces a polyclonal B-cell activation and lytic antibody production, critical for controlling parasitemia. Individuals within the chronic phase of Chagas disease may remain in an asymptomatic form (indeterminate), or develop severe cardiomyopathy (cardiac form) that can lead to death. Currently, there is no effective vaccine to prevent Chagas disease, and no treatment to halt the development of the cardiomyopathy once it is installed. The pathology associated with cardiac Chagas disease is a result of an inflammatory reaction. Thus, discovering characteristics of the host's immune response that favor the maintenance of favorable heart function may unveil important immunotherapeutic targets. Given the importance of B cells in antibody production and parasite control, we investigated T. cruzi-derived antigenic fractions responsible for B-cell activation and whether frequencies and functional characteristics of B-cell subpopulations are associated with different clinical outcomes of human Chagas disease. We stimulated cells from indeterminate (I) and cardiac (C) Chagas patients, as well as non-infected individuals (NI), with T. cruzi-derived protein- (PRO), glycolipid- (GCL) and lipid (LIP)-enriched fractions and determined functional characteristics of B-cell subpopulations. Our results showed that the frequency of B-cells was similar amongst groups. PRO, but not GCL nor LIP, led to an increased frequency of B1 B-cells in I, but not C nor NI. Although stimulation with PRO induced higher TNF expression by B1 B-cells from C and I, as compared to NI, it induced expression of IL-10 in cells from I, but not C. Stimulation with PRO induced an increased frequency of the CD11b+ B1 B-cell subpopulation, which was associated with better cardiac function. Chagas patients displayed increased IgM production, and activation of gamma-delta T-cells, which have been associated with B1 B-cell function. Our data showed that PRO activates CD11b+ B1 B-cells, and that this activation is associated with a beneficial clinical status. These findings may have implications in designing new strategies focusing on B-cell activation to prevent Chagas disease cardiomyopathy

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Activation of Human CD11b+ B1 B-Cells by Trypanosoma cruzi-Derived Proteins Is Associated With Protective Immune Response in Human Chagas Disease

Submitted by Nuzia Santos ([email protected]) on 2019-10-18T18:05:46Z No. of bitstreams: 1 Activation of Human CD11b+ B1 B-Cells.pdf: 1184928 bytes, checksum: 60dd296cf28c092dc46ba1ef0977c524 (MD5)Approved for entry into archive by Nuzia Santos ([email protected]) on 2019-10-18T18:12:17Z (GMT) No. of bitstreams: 1 Activation of Human CD11b+ B1 B-Cells.pdf: 1184928 bytes, checksum: 60dd296cf28c092dc46ba1ef0977c524 (MD5)Made available in DSpace on 2019-10-18T18:12:17Z (GMT). No. of bitstreams: 1 Activation of Human CD11b+ B1 B-Cells.pdf: 1184928 bytes, checksum: 60dd296cf28c092dc46ba1ef0977c524 (MD5) Previous issue date: 2018Universidade Federal de Minas Gerais. Departamento de Morfologia Instituto de Ciências Biológicas. Laboratório de Interações Célula-Célula. Belo Horizonte, MG, Brasil / Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Departamento de Morfologia Instituto de Ciências Biológicas. Laboratório de Interações Célula-Célula. Belo Horizonte, MG, Brasil / Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil / Fundação Oswaldo Cruz. Instituto René Rachou. Laboratório de Parasitologia Celular e Molecular. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Departamento de Morfologia Instituto de Ciências Biológicas. Laboratório de Interações Célula-Célula. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Departamento de Morfologia Instituto de Ciências Biológicas. Laboratório de Interações Célula-Célula. Belo Horizonte, MG, Brasil / Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Faculdade de Medicina. Departamento de Clínica Médica. Belo Horizonte, MG, Brasil.A. C. Camargo Centro de Câncer. Centro de Pesquisa Internacional. São Paulo, SP, Brasil / Instituto Nacional de Ciência e Tecnologia Doenças Tropicais. Belo Horizonte, MG, Brasil.Universidade Federal de Minas Gerais. Departamento de Morfologia Instituto de Ciências Biológicas. Laboratório de Interações Célula-Célula. Belo Horizonte, MG, Brasil / Universidade Federal de Minas Gerais. Pós-graduação em Parasitologia. Belo Horizonte, MG, Brasil / Instituto Nacional de Ciência e Tecnologia Doenças Tropicais. Belo Horizonte, MG, Brasil.B-cells mediate humoral adaptive immune response via the production of antibodies and cytokines, and by inducing T-cell activation. These functions can be attributed to distinct B-cell subpopulations. Infection with Trypanosoma cruzi, the causative agent of Chagas disease, induces a polyclonal B-cell activation and lytic antibody production, critical for controlling parasitemia. Individuals within the chronic phase of Chagas disease may remain in an asymptomatic form (indeterminate), or develop severe cardiomyopathy (cardiac form) that can lead to death. Currently, there is no effective vaccine to prevent Chagas disease, and no treatment to halt the development of the cardiomyopathy once it is installed. The pathology associated with cardiac Chagas disease is a result of an inflammatory reaction. Thus, discovering characteristics of the host's immune response that favor the maintenance of favorable heart function may unveil important immunotherapeutic targets. Given the importance of B cells in antibody production and parasite control, we investigated T. cruzi-derived antigenic fractions responsible for B-cell activation and whether frequencies and functional characteristics of B-cell subpopulations are associated with different clinical outcomes of human Chagas disease. We stimulated cells from indeterminate (I) and cardiac (C) Chagas patients, as well as non-infected individuals (NI), with T. cruzi-derived protein- (PRO), glycolipid- (GCL) and lipid (LIP)-enriched fractions and determined functional characteristics of B-cell subpopulations. Our results showed that the frequency of B-cells was similar amongst groups. PRO, but not GCL nor LIP, led to an increased frequency of B1 B-cells in I, but not C nor NI. Although stimulation with PRO induced higher TNF expression by B1 B-cells from C and I, as compared to NI, it induced expression of IL-10 in cells from I, but not C. Stimulation with PRO induced an increased frequency of the CD11b+ B1 B-cell subpopulation, which was associated with better cardiac function. Chagas patients displayed increased IgM production, and activation of gamma-delta T-cells, which have been associated with B1 B-cell function. Our data showed that PRO activates CD11b+ B1 B-cells, and that this activation is associated with a beneficial clinical status. These findings may have implications in designing new strategies focusing on B-cell activation to prevent Chagas disease cardiomyopathy