Mudança longitudinal na prevalência de infestação de protistas ciliados epibiontes sobre oligoquetas ao longo do rio Paraibuna, município de Juiz de Fora, Minas Gerais, Brasil

Aiming to record and analyze the prevalence of infestation by ciliated protozoa peritrichs colonizing oligochaetes along the Paraibuna River, Juiz de Fora City, Minas Gerais, a sampling of sediment was performed at different sampling stations along the Paraibuna River. The oligochaetes were screened from the fixed samples, and then examined through light microscopy, to quantify the prevalence of infestation of epibiont ciliates. Several physicochemical parameters of water were analized in all sampling sites. Rhabdostyla sp. was found only in three of the five collecting points and greater abundance of oligochaetes in some sites may be related to the preference of both peritrichs ciliates and oligochaetes for eutrophic environments, due to the fact that these points were already located in urbanized locations. The occurrence and the prevalence of epibiont pertrichs have been identified as an important tool for evaluanting water quality in lotic systems. The data suggest a direct relation between prevalence of infestation and organic pollution, that can be a direct contributor to the spread of several diseases among people who may have contact with the water of this environment.Com o objetivo de registrar e analisar a prevalência de infestação de protozoários ciliados peritríquios colonizando oligoquetas ao longo do rio Paraibuna, Juiz de Fora, Minas Gerais, foi realizada uma coleta de amostras do sedimento em diferentes estações amostrais ao longo do rio. Das amostras fixadas, foram triados os oligoquetas que, posteriormente, foram analisados sob microscópio de campo claro, para a quantificação da prevalência de infestação dos ciliados epibiontes. Foram analisados diversos parâmetros físico-químicos da água nos pontos de coleta. Houve o registro de Rhabdostyla sp. somente em três dos cinco pontos coletados e a maior abundância de oligoquetas em algumas estações pode estar relacionada com a predileção tanto dos ciliados peritríquios quanto dos oligoquetas por ambientes eutrofizados, visto que estes pontos já estavam situados em locais urbanizados. A ocorrência e a prevalência de peritríquios epibiontes têm sido apontadas como ferramentas importantes de avaliação da qualidade da água em sistemas lóticos. Os dados obtidos sugerem a relação direta entre prevalência de infestação e poluição orgânica, o que pode contribuir diretamente para a disseminação de diversas doenças em pessoas que venham a ter contato com a água deste ambiente

Avaliação do efeito dos óleos essenciais de Ocimum Gratissimum e Mentha x Villosa em linhagem de células de adenocarcinoma humano de pulmão: citotoxicidade, ciclo celular e produção de TGF- β1

Ocimum. gratissimum L. and Mentha x villosa Huds are aromatic plants largely used, in Brazil and other countries, for therapeutic and culinary purposes. Several pharmacological properties have been described for their essential oil and their major compounds: Eugenol and piperitenone oxide respectively. However, the antiproliferative effect and the blockage of the TGF-1 production are poorly understood. This cytokine contributes for the development of late-phase tumors. This study aimed to evaluate the effects of the essential oils of Ocimum gratissimum and Mentha x villosa over a TGF-1 producer human lung adenocarcinoma cell line. Methodology: Viability was assessed through MTT assay, on cell lineages (A549 and J774 A.1) and intraperitoneal macrophages treated for 48h with essential oil concentrations ranging from 5 to 200g/mL. Cell cycle and SubG1 DNA amount was evaluated through propidium iodide staining followed by flow citometry analysis. TUNEL assay was used to quantify the DNA fragmentation. ELISA was performed to measure the TGF-1 production. Results: Both essential oils reduced A549 cell viability (IC50: EOOG:160g/mL / EOMV:117g/mL), there was also cell cycle arrest at S phase, after 24hours of treatment (control: 12,31±0,89 / EOOG: 15,70±1,15 / EOMV: 23,35±0,75). SubG1 DNA amount was also elevated after treatment (control: 15,05±0,71 / EOOG: 91,94±1,71 / EOMV:24,62±1,06), an indicative of DNA fragmentation, one of the apoptosis sign. This effect was confirmed by the elevated TUNEL labeling. The non-lethal concentrations of the essential oils (10 and 50g/mL) led to the reduction of TGF-1 production. Conclusion: These data indicates the apoptotic and cell cycle arrest effects of the essential oils, mainly over TGF-1 producing tumors. As this cytokine has a key role over the survival and proliferation of these cancer cells. The possible systemic effects of these treatments are yet to be evaluated, as the TGF-1 blockage may affect the maintenance of homeostasis.Ocimum. gratissimum L. e Mentha x villosa Huds. são duas plantas aromáticas que são amplamente utilizadas no Brasil e em outros países tanto para fins terapêuticos, como na culinária. Diversas atividades farmacológicas já foram descritas para essas duas plantas e para os componentes majoritários de seus óleos essenciais, Eugenol e Óxido de Piperitenona, respectivamente. Porém ainda há a carência de estudos sobre a atividade antiproliferativa desses óleos essenciais sobre linhagens tumorais e as implicações desses compostos sobre a produção de TGF-1, uma citocina que, em tumores já estabelecidos, apresenta efeito pró-tumoral. Esse estudo visa avaliar os efeitos dos tratamentos com os óleos essenciais de O. gratissimum e M. x villosa, sobre uma linhagem de adenocarcinoma humano de pulmão produtora de TGF-1. Métodos: A viabilidade celular foi avaliada através do ensaio de MTT em linhagens de células (A549 e J774 A.1) e em macrófagos intraperitoneais tratados com 5 a 200g/mL, por 48h. O efeito dos óleos essenciais sobre o ciclo celular foi avaliado através de marcação com iodeto de propídio e quantificação das fases de ciclo celular por citometria de fluxo. A quantificação de células em SubG1 foi utilizada como parâmetro para avaliação de apoptose, que foi confirmada através da marcação de TUNEL. A produção de TGF-1 foi avaliada por ELISA. Resultados: Os dois óleos essenciais reduziram a viabilidade da linhagem celular A549 (IC50: OG:160g/mL / MV:117g/mL), os tratamentos também induziram parada do ciclo celular em S com 24h de tratamento (controle: 12,31±0,89 / OEOG: 15,70±1,15 / OEMV: 23,35±0,75) efeito já registrado para eugenol. Também houve aumento do percentual de células em SubG1 (controle: 15,05±0,71 / OEOG: 91,94±1,71 / OEMV:24,62±1,06), indicando aumento da fragmentação de DNA, um dos sinais de apoptose, que foi confirmado pelo aumento da mediana de fluorescência na marcação de TUNEL (controle:59.1±3.4 / OEOG:68.6±3.7 / OEMV:75.3±15.7). Houve redução da produção de TGF-1 nas concentrações não letais dos óleos essenciais (10 e 50g/mL). Conclusões: Esses dados demonstram o potencial indutor de apoptose e de parada de ciclo celular, desses óleos essenciais para o tratamento de tumores, sobretudo aqueles caracterizados pela produção de TGF-1, citocina importante para a sobrevivência e proliferação de células tumorais. Contudo, essa citocina desempenha papéis importantes na homeostase do organismo, e por isso são necessários estudos que avaliem o efeito sistêmico desses óleos essenciais.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCNPq - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerai

Obesidade e asma: alterações da resposta imune em órgãos linfóides periféricos e efeito do tratamento com azitromicina

Both asthma and obesity present rising prevalence. Their concomitance is a reason for concern, as obese individuals present higher exacerbation rates, are refractory to conventional treatments and display a distinct phenotype of the disease. The occurrence of neutrophilia, over the establishment of the eosinophilia; associated with low IgE titers is one of the marks of obese-asthmatics. However, the influence of obesity on the immune response on the peripheral lymphoid organs, during allergic asthma development is still unknown, mainly when it comes to B cells and follicular helper T cells (TFH), the main components of the germinal centers. In addition, recent effort has been done towards the development of more efficient treatments for these patients. Among those alternatives, the use of macrolides, as azithromycin, can be highlighted as good approach for resistant-asthma, associated with neutrophilia. Therefore, the present study aimed to evaluate the obesity effects over the immunopathological mechanisms involved OVA/HDM-induced pulmonary allergy and the effect of azithromycin over these models. Histological analysis, cytokines quantification and lung function evaluation were performed on top of immunophenotyping of the cells from the peripheral lymphoid organs, during the allergic response. The immune response was dampened from the epithelium, as shown by the diminished IL-25 and TSLP production, associated with the diminished activation and migration of dendritic cells to the lymph nodes. The immune response observed in the peripheral lymphoid organs was affected, with B cell and TFH regulation, associated with increased follicular regulatory T cells (TFR) differentiation. Those organs displayed distinct allergic features, with greater obesity influence over the spleen, promoting the TH17 polarization; and TH2 exacerbation on the lymph nodes. Those changes were associated with low IgE titers and increased IgG2a levels. Meanwhile, the lungs exhibited an increased neutrophilia, over the eosinophilia, associated with the diminished CCL11 expression. The azithromycin treatment reduced several parameters related to asthma, as the neutrophilia, the TH17 response, the expression of neutrophil chemoattractants, (KC and MIP2), on top of the reduction of the bronchial hyperresponsiviness on obese allergic animals. In addition, the treatment also reduced the B cells and TFH frequency on their lymph nodes, followed by diminished frequencies of IL-4, IL-17A e IFN producing TH cells. Additionally, obese-allergic treated animals overexpressed mir155 in their lungs. However the treatment did not affect the TH2/eosinophilic response, and it even had worsen the neutrophilic response on lean allergic mice. Altogether, these results demonstrate obesity affects asthma development on the peripheral lymphoid organs, and also, azithromycin was efficient on the treatment of the neutrophilic profile of the obesity aggravated allergy.Asma e obesidade são doenças que acometem um número crescente de indivíduos. A concomitância das mesmas é razão de preocupação, tendo em vista que indivíduos obesos apresentam uma maior taxa de exacerbação da asma, são mais resistentes aos tratamentos convencionais e apresentam um fenótipo distinto da doença. A ocorrência de neutrofilia, em detrimento da eosinofilia; associado a baixos níveis de IgE é uma característica de obesos-asmáticos. Entretanto, pouco se sabe sobre a influência da obesidade na reposta imune em órgãos linfoides periféricos durante o desenvolvimento da asma alérgica, principalmente sobre os principais componentes dos centros germinativos, linfócitos B e T foliculares (TFH). Além disso, estudos tem buscado desenvolver tratamentos mais eficazes pra esse subgrupo de pacientes. Dentre essas alternativas o uso de antibióticos macrolídeos, como a azitromicina pode ser uma forma de tratar casos de asma resistente, que apresentem um perfil neutrofílico. Portanto, o presente trabalho teve como objetivo avaliar o efeito da obesidade sobre os mecanismos envolvidos na imunopatogênese da alergia pulmonar experimental induzida por OVA/HDM, bem como avaliar o efeito da azitromicina nesses modelos. Além dos parâmetros histológicos, dosagem de citocinas e avaliação da função pulmonar, também foi avaliada por imunofenotipagem a composição da população de células nos órgãos linfoides periféricos, durante a reposta alérgica. Foi observado um dano à resposta imune em animais obesos alérgicos desde o epitélio, com a menor produção de IL-25 e TSLP, associada a menor ativação e migração de células dendríticas para os linfonodos. Nos órgãos linfoides periféricos foi observado um perfil diferenciado de resposta, com regulação de células B e TFH, e maior diferenciação de células T foliculares regulatórias. Além disso, esses órgãos apresentaram respostas alérgicas distintas, com uma maior influência da obesidade no baço, promovendo a polarização para TH17; e exacerbação do perfil TH2 nos linfonodos. Essas modificações refletiram nos menores níveis de IgE e aumento de IgG2a. Nos pulmões houve aumento de neutrofilia e redução da eosinofilia, associado a menor produção de CCL11. O tratamento com azitromicina reduziu muitos parâmetros relacionados à asma, dentre eles, a neutrofilia, a resposta TH17, bem como a expressão de fatores quimioatraentes para neutrófilos, como KC e MIP-2; além da hiperresponsividade brônquica em obesos-alérgicos. Em adição, o tratamento também reduziu a frequência de LB e TFH nos linfonodos desses animais, acompanhado da menor frequência de células TH produtoras de IL-4, IL-17A e IFN. Somado a isso, animais obesos alérgicos tratados apresentaram maior expressão de mir-155 nos pulmões. Entretanto, o tratamento não afetou a resposta de perfil TH2/eosinofílica, além de agravar a resposta neutrofílica em alérgicos magros. Esses resultados demonstram que a obesidade afeta o desenvolvimento da asma nos órgãos linfoides periféricos, e ainda, que a azitromicina foi eficiente no tratamento do perfil neutrofílico de resposta, característico de um quadro alérgico agravado pela obesidade

Proteínas de checkpoint imunológico como novo alvo da imunoterapia contra o câncer: revisão da literatura

A new era in cancer treatment is emerging with the use of antibodies directed against immune checkpoint proteins, known as “checkpoint inhibitors”. A novel concept of “magic bullets”, concepted by Paul Ehrlich at the beginning of the last century, as being capable of acting directly on the destruction of tumor targets, is now represented by antibodies directed against molecules which block the antitumor activity of the immune system, such as Cytotoxic T Lymphocyte Antigen-4 (CTLA-4) and Programmed Cell Death Protein-1 (PD-1). These new immunotherapies have revolutionized the treatment of different cancer types. Studies on CTLA-4, PD-1, and their ligands in antigen presenting cells are discussed in this review. The importance of tumor antigen discovery and the role of the immune system in immune surveillance of tumors were highlighted. Also in the present study, aspects related to the effects of immunotherapies based on the use of anti-CTLA-4 and anti-PD-1/ PD-L1 monoclonal antibodies are described, such as the risk of stimulating responses tonormal tissues and other adverse effects, as well as the use of combination therapies which can improve the efficacy of cancer treatment.Uma nova era no tratamento do câncer está surgindo com o uso de anticorpos capazes de inibir pontos de bloqueio do sistema imunológico, chamados de “inibidores de checkpoint”. Um novo conceito de “balas mágicas”, que no início do século passado foram imaginadas por Paul Ehrlich como capazes de atuar diretamente na destruição de alvos tumorais, é representado agora por anticorpos direcionadas contra moléculas que bloqueiam a atividade antitumoral do sistema imunológico, como o antígeno-4 de linfócito T citotóxico (CTLA-4) e a proteína-1 de morte celular programada (PD-1). Essas novas imunoterapias vêm revolucionando a forma de tratar diferentes tipos de câncer. Nesta revisão selecionamos estudos sobre CTLA-4 e PD-1, seus ligantes em células apresentadoras de antígenos, assim como destacamos a importância da descoberta de antígenos tumorais e o papel do sistema imunológico na imunovigilância tumoral. Nesse estudo são discutidos aspectos relacionados aos efeitos de imunoterapias baseadas no uso de anticorpos monoclonais anti-CTLA-4 e anti-PD-1/ PD-L1, como o risco de serem estimuladas respostas direcionadas a tecidos saudáveis e outros efeitos adversos, bem como o uso de terapias combinadas que podem contribuir para melhorar a eficiência do tratamento do câncer

Efficiency of rLb6H recombinant protein from Leishmania (Viannia) braziliensis for the detection of canine visceral leishmaniasis: Efficacy of rLb6H in CVL diagnosis

Introduction: Visceral leishmaniasis (VL) is a serious endemic disease in many tropical and subtropical countries, with a strong incidence in Brazil. The disease is transmitted by the bite of infected female sandflies, with dogs being the main urban reservoirs of the parasite. The diverse clinical profile and the long incubation period are challenges for the diagnosis of canine visceral leishmaniasis (CVL). Recombinant proteins from Leishmania spp have been studied as antigens that can increase the accuracy of serological tests. Aim: We aimed to evaluate the diagnostic performance of the recombinant protein rLb6H, from Leishmania brasiliensis, in comparison to the reference antigens rK39 and rK28, from L. donovani, prioritizing the identification of subclinical infected dogs. Materials and Methods: Serum IgG reactivity to rLb6H, rK28, and rK39 recombinant proteins was assessed in dogs with previously parasitological confirmation of CVL, subdivided according to their clinical status, using immunoenzymatic assay (ELISA). Diagnostic accuracy of each ELISA was evaluated by receiver operating characteristic (ROC) curve analysis. Results: As expected, while all antigens showed a better performance in detecting CVL in symptomatic dogs (SD), detection of CVL in the oligosymptomatic (OD) and asymptomatic (AD) groups was lower, but rLb6H achieved high sensitivity for asymptomatic CVL. Interestingly, the most reactive CVL samples to rK28 were barely detected by rLb6H, while the less reactive to rK28, mostly from the AD group, presented higher reactivity to rLb6H. Conclusion: The recombinant protein rLb6H showed utility in the detection of asymptomatic CVL, displaying a complementary reactivity to rK39 and rK28. Thus, these results suggest that rLb6H could be incorporated into multi-antigen strategies, to increase diagnostic accuracy of visceral leishmaniasis.Introduction: Visceral leishmaniasis (VL) is a serious endemic disease in many tropical and subtropical countries, with a strong incidence in Brazil. The disease is transmitted by the bite of infected female phlebotomine sandflies, with dogs being the main urban reservoirs of the parasite. The diverse clinical profile and the long incubation period are challenges for the diagnosis of canine visceral leishmaniasis (CVL). Recombinant proteins from Leishmania spp. have been studied as antigens that can increase the accuracy of serological tests. Objective: To evaluate the diagnostic performance of the recombinant protein rLb6H, from Leishmania braziliensis, in comparison to the reference antigens rK39 and rK28, from L. donovani, prioritizing the identification of subclinical infected dogs. Material and Methods: Serum IgG reactivity to rLb6H, rK28, and rK39 recombinant proteins was assessed in dogs with previously parasitological confirmation of CVL, subdivided according to their clinical status, using immunoenzymatic assay (ELISA). Diagnostic accuracy of each ELISA was evaluated by receiver operating characteristic (ROC) curve analysis. Results: While all antigens showed a better performance in detecting CVL in symptomatic dogs (SD), detection of CVL in the oligosymptomatic (OD) and asymptomatic (AD) groups was lower, but rLb6H achieved high sensitivity for asymptomatic CVL. Interestingly, the most reactive CVL samples to rK28 were barely detected by rLb6H, while the less reactive to rK28, mostly from the AD group, presented higher reactivity to rLb6H. Conclusion: The recombinant protein rLb6H showed utility in the detection of asymptomatic CVL, displaying a complementary reactivity to rK39 and rK28. Thus, these results suggest that rLb6H could be incorporated into multi-antigen strategies, to increase diagnostic accuracy of CVL

Structural Effects on the Antioxidant Properties of Amino Acid Betaxanthins

Betaxanthins are natural products with high antioxidant and anti-inflammatory properties. Here, we describe the semisynthesis of twenty-one betaxanthins derived from proteinogenic amino acids, including the elusive betaxanthin of l-cysteine and two betaxanthins derived from l-lysine, and rationalize their antioxidant properties in mechanistic terms. The antioxidant capacity and redox potential of these betaxanthins were compared to those of model betaxanthins derived from dopamine, l-DOPA (L-3,4-dihydroxyphenylalanine), and pyrrolidine and structure–property relationships were established by using matched molecular pair analysis and a model developed using a genetic algorithm. Either a phenol or indole moiety enhance the antioxidant capacity of betaxanthins, which is overall much higher than that of their amino acid precursors and standard antioxidants, except for the cysteine-betaxanthin. The one-electron oxidation of amino acid betaxanthins produces radicals stabilized in multiple centers, as demonstrated by quantum chemical calculations

Design of an Antioxidant Nitrone Scaffold Based on Plant Pigments

Nitrones derived from natural antioxidants are emerging as highly specific therapeutics against various human diseases, including stroke, neurodegenerative pathologies, and cancer. However, the development of useful pseudo-natural nitrones requires the judicious choice of a secondary metabolite as the precursor. Betalains are nitrogen-containing natural pigments that exhibit marked antioxidant capacity and pharmacological properties and, hence, are ideal candidates for designing multifunctional nitrones. In this work, we describe the semisynthesis and properties of a biocompatible, antioxidant betalain-nitrone called OxiBeet. This bio-based compound is a better radical scavenger than ascorbic acid, gallic acid, and most non-phenolic antioxidants and undergoes concerted proton-coupled electron transfer. The autoxidation of OxiBeet produces a persistent nitroxide radical, which, herein, is studied via electron paramagnetic resonance spectroscopy. In addition, femtosecond transient absorption spectroscopy reveals that excited state formation is not required for the oxidation of OxiBeet. The results are compared with those obtained using betanin, a natural betalain, and pBeet, the imine analog of OxiBeet. The findings of this study will enable the development of antioxidant nitrones based on the novel N-oxide 1,7-diazaheptamethinium scaffold and betalain dyes with enhanced hydrolytic stability in aqueous alkaline media. </div

Autotransplantation of Spleen Mitigates Drug-Induced Liver Damage in Splenectomized Mice

Purpose: The spleen presents numerous functions, including the production of immunoglobulins and blood filtration, removing microorganisms and cellular debris. The spleen also has anatomical and functional relationship with the liver, but there are few studies on this topic. The aim of this study was to assess the effect of splenectomy and autologous spleen transplantation on both filtering functions of spleen and acetaminophen-induced hepatotoxicity. Materials and Methods: Fifty-two BALB/c mice were randomized into four groups: splenectomized; splenectomy and splenic autotransplantation in the greater omentum; sham operated control; and non-operated control. At day 7th, 14th, and 28th after surgery, splenic filtration was assessed by counting Howell-Jolly bodies (HJB) and pitted red cells (PIT). The animals received 400 mg/kg acetaminophen by gavage at day 28th and after 12 or 24 hours were euthanized for evaluation of splenic and hepatic morphology. Results: The splenectomized group demonstrated reduced filtration of HJB and PIT in all analyzes, while the autotransplanted group developed progressive recovery of function after the 14th day. At day 28 after surgery the implants showed similar histology in comparison to normal spleen. Liver histology showed more intense centrilobular necrosis in splenectomized group in comparison to the others, suggesting a protective role of spleen in acetaminophen-induced liver injury. Conclusions: Splenic implants showed structural and functional recovery, demonstrating the ability of autologous implant to rescue filtering function of intact spleen. Furthermore, the integrity of splenic function appears to influence liver morphology, since the presence of the splenic implants mitigated the effects of chemically-induced liver damage

ATLANTIC ANTS: a data set of ants in Atlantic Forests of South America

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