44 research outputs found

    Influence of different restraint protocols for the electrocardiogram values of feline night monkeys (Aotus azarae infulatus

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    Universidade do Estado do ParĂĄ. Centro de CiĂȘncias BiolĂłgicas e da SaĂșde. LaboratĂłrio de Cirurgia Experimental. BelĂ©m, PA, Brasil.Universidade Federal Rural da AmazĂŽnia. Instituto de SaĂșde e Produção Animal. BelĂ©m, PA, Brasil.MinistĂ©rio da SaĂșde. Secretaria de VigilĂąncia em SaĂșde. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil.MinistĂ©rio da SaĂșde. Secretaria de VigilĂąncia em SaĂșde. Instituto Evandro Chagas. Centro Nacional de Primatas. Ananindeua, PA, Brasil.Universidade Federal Rural da AmazĂŽnia. Instituto de SaĂșde e Produção Animal. BelĂ©m, PA, Brasil.Universidade do Estado do ParĂĄ. Centro de CiĂȘncias BiolĂłgicas e da SaĂșde. LaboratĂłrio de Cirurgia Experimental. BelĂ©m, PA, Brasil.Macacos-da-noite sĂŁo muito susceptĂ­veis ao estresse e por isso a contenção quĂ­mica ou fĂ­sica deve ser cuidadosamente avaliada antes de qualquer procedimento. Protocolos anestĂ©sicos podem alterar alguns parĂąmetros fisiolĂłgicos, sendo o eletrocardiograma (ECG) um exame muito utilizado para avaliação do ritmo e da frequĂȘncia cardĂ­aca. O objetivo deste estudo foi avaliar a influĂȘncia de quatro diferentes protocolos de contenção sobre o ECG realizado em Aotus azarae infulatus. Para isso foram utilizados 10 animais, machos, adultos, submetidos Ă  contenção com a associação tiletamina/zolazepam (TZ), isoflurano (ISO), associação cetamina e midazolam (CET) e contenção fĂ­sica (CF). NĂŁo foram observadas diferenças nos parĂąmetros de ondas e complexos obtidos no ECG em todos os grupos testados, no entanto, durante a avaliação do traçado os animais do grupo CF apresentaram uma quantidade maior de alteraçÔes. Concluiu-se que os protocolos de contenção utilizados nĂŁo alteraram os valores do ECG e que nĂŁo foi possĂ­vel considerar o grupo CF como controle devido causar mais alteraçÔes do que todos os protocolos testados

    Experimental Chemotherapy for Chagas Disease: A Morphological, Biochemical, and Proteomic Overview of Potential Trypanosoma cruzi Targets of Amidines Derivatives and Naphthoquinones

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    Chagas disease (CD), caused by Trypanosoma cruzi, affects approximately eight million individuals in Latin America and is emerging in nonendemic areas due to the globalisation of immigration and nonvectorial transmission routes. Although CD represents an important public health problem, resulting in high morbidity and considerable mortality rates, few investments have been allocated towards developing novel anti-T. cruzi agents. The available therapy for CD is based on two nitro derivatives (benznidazole (Bz) and nifurtimox (Nf)) developed more than four decades ago. Both are far from ideal due to substantial secondary side effects, limited efficacy against different parasite isolates, long-term therapy, and their well-known poor activity in the late chronic phase. These drawbacks justify the urgent need to identify better drugs to treat chagasic patients. Although several classes of natural and synthetic compounds have been reported to act in vitro and in vivo on T. cruzi, since the introduction of Bz and Nf, only a few drugs, such as allopurinol and a few sterol inhibitors, have moved to clinical trials. This reflects, at least in part, the absence of well-established universal protocols to screen and compare drug activity. In addition, a large number of in vitro studies have been conducted using only epimastigotes and trypomastigotes instead of evaluating compounds' activities against intracellular amastigotes, which are the reproductive forms in the vertebrate host and are thus an important determinant in the selection and identification of effective compounds for further in vivo analysis. In addition, due to pharmacokinetics and absorption, distribution, metabolism, and excretion characteristics, several compounds that were promising in vitro have not been as effective as Nf or Bz in animal models of T. cruzi infection. In the last two decades, our team has collaborated with different medicinal chemistry groups to develop preclinical studies for CD and investigate the in vitro and in vivo efficacy, toxicity, selectivity, and parasite targets of different classes of natural and synthetic compounds. Some of these results will be briefly presented, focusing primarily on diamidines and related compounds and naphthoquinone derivatives that showed the most promising efficacy against T. cruzi

    Bentonites Modified with Phosphomolybdic Heteropolyacid (HPMo) for Biowaste to Biofuel Production

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    Two bentonites from ParaĂ­ba (Northeastern Brazil) were impregnated with heteropoly phosphomolybdic H3PMo12O40 (HPMo). The materials produced were characterized by various techniques such as N2 adsorption-desorption (specific surface area, SSA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA/DTG), Scanning Electron Microscopy (SEM) equipped with Dispersive Energy X-ray spectroscopy (EDS), ultraviolet-visible spectroscopy (UV-vis), acid-base titration analysis. The catalytic activity of these materials was tested in the esterification of a waste from palm oil deodorization and the main results obtained (about 93.3% of conversion) indicated that these materials have potential to act as heterogeneous solid acid catalysts. The prepared materials exhibited satisfactory catalytic performance even after a very simple recycling process in three reuse cycles, without significant loss of their activities

    Hypotensive effect and endothelium-dependent vascular action of leaves of Alpinia purpurata (Vieill) K. Schum

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    The aims of this study were to evaluate the chemical profile, vascular reactivity, and acute hypotensive effect (AHE) of the ethanolic extract of leaves of Alpinia purpurata (Vieill) K. Schum (EEAP). Its chemical profile was evaluated using HPLC-UV, ICP-OES, and colorimetric quantification of total flavonoids and polyphenols. The vascular reactivity of the extract was determined using the mesenteric bed isolated from WKY. AHE dose-response curves were obtained for both EEAP and inorganic material isolated from AP (IAP) in WKY and SHR animals. Cytotoxic and mutagenic safety levels were determined by the micronucleus test. Rutin-like flavonoids were quantified in the EEAP (1.8 ± 0.03%), and the total flavonoid and polyphenol ratios were 4.1 ± 1.8% and 5.1 ± 0.3%, respectively. We observed that the vasodilation action of EEAP was partially mediated by nitric oxide (·NO). The IAP showed the presence of calcium (137.76 ± 4.08 Όg mg-1). The EEAP and IAP showed an AHE in WKY and SHR animals. EEAP did not have cytotoxic effects or cause chromosomic alterations. The AHE shown by EEAP could result from its endothelium-dependent vascular action. Rutin-like flavonoids, among other polyphenols, could contribute to these biological activities, and the calcium present in EEAP could act in a synergistic way

    Pervasive gaps in Amazonian ecological research

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