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Anais da Academia Brasileira de Ciências, Volume: 91 Suplemento 1, Publicado: 2019
  • EDITORIAL NOTE: Special Volume by the Affiliated Members of the Brazilian Academy of Sciences Editorial

    KELLNER, ALEXANDER W.A.
  • Bohnenblust-Hille inequalities: analytical and computational aspects Mathematical Sciences

    CAVALCANTE, WASTHENNY V.; PELLEGRINO, DANIEL M.

    Resumo em Inglês:

    Abstract The Bohnenblust-Hille polynomial and multilinear inequalities were proved in 1931 and the determination of exact values of their constants is still an open and challenging problem, pursued by various authors. The present paper briefly surveys recent attempts to attack/solve this problem; it also presents new results, like connections with classical results of the linear theory of absolutely summing operators, and new perspectives.
  • Strategies Towards the Synthesis of N2-Substituted 1,2,3-Triazoles Chemical Sciences

    SOUZA, RODRIGO OCTÁVIO M.A. DE; MIRANDA, LEANDRO S. DE MARIZ E

    Resumo em Inglês:

    Abstract The chemistry of 1,2,3-triazoles gained much attention since the discovery of the copper catalyzed Alkyne-azide cycloaddition (CuAAC) reaction which delivers exclusively the 1,4-regioisomer in high yields. On the other hand there is still no universal methodology capable of delivering the N2 substituted regioisomer. The unique properties of these N2-substituted 1,2,3-triazoles have stimulated synthetic efforts on the developments of methodologies capable of delivering it in high yield and selectivity. These efforts are the subject of the presented review.
  • Mercury exposure of children living in Amazonian villages: influence of geographical location where they lived during prenatal and postnatal development Chemical Sciences

    FREITAS, JOYCE S.; LACERDA, ELIZA MARIA C.B.; RODRIGUES JÚNIOR, DARIO; CORVELO, TEREZA CRISTINA O.; SILVEIRA, LUIZ CARLOS L.; PINHEIRO, MARIA DA CONCEIÇÃO N.; SOUZA, GIVAGO S.

    Resumo em Inglês:

    Abstract: Introduction: In some Amazonian river basins, hair mercury concentration is above the recommended levels. We evaluated the influence of birth geographical location in the hair mercury level of Amazonian riverine children. Materials and Methods: Hair mercury concentration was measured in 219 children living in four Amazonian riverine communities: Tapajós River (São Luiz do Tapajós and Barreiras villages, n = 110), Tocantins River (Limoeiro do Ajurú village, n = 61), and Caeté River (Caratateua village, n = 48). We used Poisson regression analysis to evaluate the association between native and non-native children from each village and its hair mercury concentration. Results: Higher mercury exposure was found in native children from São Luiz do Tapajós (range = 0.81-22.38 µg/g) followed by native children from Barreiras (range = 0.48-13.46 µg/g), non-native children from São Luiz do Tapajós (range = 0.26-22.18 µg/g), non-native children from Barreiras (range = 0.43-20.76 µg/g), followed by the children from Caeté and Tocantins river basins. We observed that Tapajós villages’ native children had higher prevalence of mercury exposure children than other children (p < 0.05). Conclusions: Birth geographical location has association to mercury levels in the hair of children who lived in a same community with history of mercury exposure.
  • An overview of the Brazilian contributions to Green Analytical Chemistry Chemical Sciences

    GAMA, MARIANA R.; MELCHERT, WANESSA R.; PAIXÃO, THIAGO R.L.C.; ROCHA, FÁBIO R.P.

    Resumo em Inglês:

    Abstract: Green Analytical Chemistry (GAC) is a research field that seeks for more sustainable analytical approaches to minimize the toxicity and amounts of wastes without hindering the analytical performance. This is a trend in Analytical Chemistry worldwide and because of the diversity of innovations on this subject, Brazil stands out as the third in the list of the main contributors to GAC, with ca. 11.2% of the published articles. Significant innovations and interesting applications in several fields have been presented and Brazil is continuously moving from Chemistry to Green Chemistry also in the Analytical Chemistry field. Selected contributions for sample preparation, spectro- and electroanalysis, separation techniques, chemometrics, and also procedures for point-of-care measurements are critically reviewed.
  • Arthritic lesions and congenital fusion in foot bones of Panochthus sp. (Xenarthra, Cingulata) Earth Sciences

    BARBOSA, FERNANDO HENRIQUE DE S.; PORPINO, KLEBERSON DE O.; ROTHSCHILD, BRUCE M.; CABRAL, UIARA G.; BERGQVIST, LILIAN P.

    Resumo em Inglês:

    ABSTRACT A set of lesions are re-described and new pathological findings in foot bones of Panochthus sp. (Xenarthra, Cingulata) are presented. The material reexamined in fact presents enthesiophytes instead of osteoartrithis, as previously interpreted. Furthermore, Calcium Pyrophosphate Deposition Disease (CPPD) was observed, a lesion absent in previous report. CPPD also was found in another set of foot bones and it was associated with a congenital fusion of two sesamoids. The material studied were collected in two natural tank deposits, one in Paraíba (material reexamined) and other in Rio Grande do Norte (new pathological findings) State.
  • Drought monitoring in the Brazilian Semiarid region Earth Sciences

    ALVALÁ, REGINA C.S.; CUNHA, ANA PAULA M.A.; BRITO, SHEILA S.B.; SELUCHI, MARCELO E.; MARENGO, JOSÉ A.; MORAES, OSVALDO L.L.; CARVALHO, MAGOG A.

    Resumo em Inglês:

    ABSTRACT Drought is a natural and recurrent phenomenon. It is considered ‘a natural disaster’ whenever it occurs in an intensive manner in highly populated regions, resulting in significant damage (material and human) and loss (socioeconomic). This paper presents the efforts developed to monitor the impact of drought in the semiarid region of Northeast Brazil. In this scope, information from different sources is compiled to support the evaluation and identification of impacted municipalities, with the main objective of supporting emergency actions to mitigate their impact. In the semiarid region of Brazil there are frequent occurrences of dry periods during the rainy season, which, depending on the intensity and duration, can cause significant damage to family-farmed crops, with a farming system characterized by low productivity indices. However, rain-fed agriculture has great economic expression and high social importance due to the region is densely occupied, and contributes to the establishment of communities in the countryside. Specifically, in the present study, the methodology adopted to monitor the impact of agricultural droughts, including an analysis of the hydrological year 2015-2016, is presented, considering different water stress indicators for the identification of the affected municipalities and assessment of the methods and tools developed.
  • The rates and players of denitrification, dissimilatory nitrate reduction to ammonia (DNRA) and anaerobic ammonia oxidation (anammox) in mangrove soils Earth Sciences

    LUVIZOTTO, DANICE M.; ARAUJO, JULIANA E.; SILVA, MICHELE DE CÁSSIA P.; DIAS, ARMANDO C. F.; KRAFT, BEATE; TEGETMEYE, HALINA; STROUS, MARC; ANDREOTE, FERNANDO D.

    Resumo em Inglês:

    Abstract Mangroves are ecosystems located in the transition zone between land and sea, characterized by periodic flooding that confer to its unique characteristics. Little is known about the transformation of nutrients that occur during the organic matter degradation in this system. In this study, we monitor the nitrogen transformations in soils from three mangroves with distinct levels of contamination using labeled 15NO3-. We also screened the mangroves metagenomes for the presence of genes that encode enzymes involved in denitrification (nirS, nirK, nosZ, norB and narG), anaerobic oxidation of ammonia (anammox) (hh, hao and hzo) and dissimilatory nitrate reduction to ammonium (DNRA) (nrfA). The transformations of 15NO3- indicated the balance of denitrification over anammox and DNRA in all three mangroves, with lower rates of processes in the mangrove affected by oil contamination. The metagenomic analysis detected 56 sequences related to denitrification, 19 with anammox and 6 with DNRA. Genes related with denitrification were phylogenetically distributed among several groups of bacteria (mainly Gammaproteobacteria). Anammox and DNRA related sequences were affiliated with Planctomycetes and Gammaproteobacteria, respectively. Thus, metagenomic and functional approaches supported the description of denitrification, anammox and DNRA rates in mangrove soils, and identified the major bacterial groups involved in these processes.
  • Generation of a triple-fluorescent mouse strain allows a dynamic and spatial visualization of different liver phagocytes in vivo Biological Sciences

    NAKAGAKI, BRENDA N.; FREITAS-LOPES, MARIA A.; CARVALHO, ÉRIKA; CARVALHO-GONTIJO, RAQUEL; CASTRO-OLIVEIRA, HORTÊNCIA M.; REZENDE, RAFAEL M.; CARA, DENISE C.; SANTOS, MÔNICA M.; LOPES, RODRIGO PESTANA; DAVID, BRUNA A.; MENEZES, GUSTAVO B.

    Resumo em Inglês:

    ABSTRACT Resident and circulating immune cells have been extensively studied due to their almost ubiquitous role in cell biology. Despite their classification under the “immune cell department”, it is becoming increasingly clear that these cells are involved in many different non-immune related phenomena, including fetus development, vascular formation, memory, social behavior and many other phenotypes. There is a huge potential in combining high-throughput assays - including flow cytometry and gene analysis - with in vivo imaging. This can improve our knowledge in both basic and clinical cell biology, and accessing the expression of markers that are relevant in the context of both homeostasis and disease conditions might be instrumental. Here we describe how we generated a novel mouse strain that spontaneously express three different fluorescence markers under control of well-studied receptors (CX3CR1, CCR2 and CD11c) that are involved in a plethora of stages of cell ontogenesis, maturation, migration and behavior. Also, we assess the percentage of the expression and co-expression of each marker under homeostasis conditions, and how these cells behave when a local inflammation is induced in the liver applying a cutting-edge technology to image cells by confocal intravital microscopy.
  • Molecular epidemiology of 16S rRNA methyltransferase in Brazil: RmtG in Klebsiella aerogenes ST93 (CC4) Biological Sciences

    PASSARELLI-ARAUJO, HEMANOEL; PALMEIRO, JUSSARA K.; MOHARANA, KANHU C.; PEDROSA-SILVA, FRANCISNEI; DALLA-COSTA, LIBERA M.; VENANCIO, THIAGO M.

    Resumo em Inglês:

    Abstract Aminoglycosides are a class of antibiotics that play a key role in antimicrobial treatment of Multidrug resistant (MDR) Gram-negative bacilli, typically in combination with β-lactams. Ribosomal 16S RNA modification by methyltransferases (e.g. RmtG) is an aminoglycoside resistance mechanism that, along with the occurrence carbapenem-resistant Enterobacteriaceae (CRE), has become a clinical concern. In Brazil, rmtG genes were initially reported in Klebsiella pneumoniae, and monitoring isolates from other species carrying this gene is critical for epidemiological studies and to prevent dissemination. Here we report the presence of rmtG in Klebisella aerogenes D3 and characterize its genetic context in comparison to isolates from other species. Further, we performed a phylogenetic reconstruction of 900 16S rRNA methyltransferases (16S-RMTases) and methyltransferase-related proteins. We show that, in K. aerogenes D3, rmtG co-occurs with sul2, near a transposon with an IS91-like insertion sequence. Resistome analysis revealed the co-production of RmtG and CTX-M-59. Ongoing surveillance of 16S-RMTases is crucial to delay the dissemination of such multiresistant isolates. Our results also highlight the reduction in treatment options for CRE infections, as well as the need of expanding prevention measures of these pathogens worldwide.
  • Composition and ecology of a snake assemblage in an upland forest from Central Amazonia Biological Sciences

    MASSELI, GABRIEL S.; BRUCE, ALLAN D.; SANTOS, JUCIMARA G. DOS; VINCEN, TIMOTHY.; KAEFER, IGOR L.

    Resumo em Inglês:

    Abstract: Most species of Amazonian snakes have wide geographic distributions. However, local environmental factors influence the formation of assemblages in different localities. In this study, we investigated the composition of the assemblage and the effect of environmental variables on the distribution of the species inhabiting an upland forest in the Experimental Farm area of the Federal University of Amazonas in Manaus, Brazil. Data collection was carried out in 24 standardized plots. Each plot was sampled four times between July 2015 and April 2017 by active search method. We recorded 83 individuals from 29 species belonging to six families. The richness in the study area corresponded to 78% of the snake species and 100% of the families previously recorded for Manaus. As observed in other localities, the most abundant species was the Amazonian lancehead (Bothrops atrox). Multiple linear regression models did not detect any effect of environmental variables on species richness and abundance of individuals. However, quadratic polynomial regression models revealed that intermediate canopy opening percentages positively influence the richness and abundance of snakes. It is possible that the result is related to a tradeoff between the thermoregulation behavior of these animals and to their susceptibility to predation.
  • Animal models in biological and biomedical research - experimental and ethical concerns Biomedical Sciences

    ANDERSEN, MONICA L.; WINTER, LUCILE M.F.

    Resumo em Inglês:

    ABSTRACT Animal models have been used in experimental research to increase human knowledge and contribute to finding solutions to biological and biomedical questions. However, increased concern for the welfare of the animals used, and a growing awareness of the concept of animal rights, has brought a greater focus on the related ethical issues. In this review, we intend to give examples on how animals are used in the health research related to some major health problems in Brazil, as well as to stimulate discussion about the application of ethics in the use of animals in research and education, highlighting the role of National Council for the Control of Animal Experimentation (Conselho Nacional de Controle de Experimentação Animal - CONCEA) in these areas. In 2008, Brazil emerged into a new era of animal research regulation, with the promulgation of Law 11794, previously known as the Arouca Law, resulting in an increased focus, and rapid learning experience, on questions related to all aspects of animal experimentation. The law reinforces the idea that animal experiments must be based on ethical considerations and integrity-based assumptions, and provides a regulatory framework to achieve this. This review describes the health research involving animals and the current Brazilian framework for regulating laboratory animal science, and hopes to help to improve the awareness of the scientific community of these ethical and legal rules.
  • A giant on the ground: another large-bodied Atractus (Serpentes: Dipsadinae) from Ecuadorian Andes, with comments on the dietary specializations of the goo-eaters snakes Biomedical Sciences

    PASSOS, PAULO; SCANFERLA, AGUSTÍN; MELO-SAMPAIO, PAULO R.; BRITO, JORGE; ALMENDARIZ, ANA

    Resumo em Inglês:

    ABSTRACT Body-size is significantly correlated with the number of vertebrae (pleomerism) in multiple vertebrate lineages, indicating that somitogenesis process is an important factor dictating evolutionary change associated to phyletic allometry and, consequently, species fitness and diversification. However, the role of the evolution of extreme body sizes (dwarfism and gigantism) remains elusive in snakes, mainly with respect to postnatal ontogeny in dietary preferences associated with evolution of gigantism in many lineages. We described herein a new species in the highly diversified and species-rich genus Atractus on the basis of four specimens from the southeastern slopes of the Ecuadorian Andes. The new species is morphologically similar and apparently closely related to two other allopatric giant congeners (A. gigas and A. touzeti), from which it can be distinguished by their distinct dorsal and ventral coloration, the number of supralabial and infralabial scales, the number of maxillary teeth, and relative width of the head. In addition, we discuss on the ontogenetic trajectories hypotheses and dietary specializations related to evolution of gigantism in the goo-eaters genus Atractus.
  • Molecular farming of antimicrobial peptides: available platforms and strategies for improving protein biosynthesis using modified virus vectors Agrarian Sciences

    LEITE, MICHEL L.; SAMPAIO, KAMILA B.; COSTA, FABRÍCIO F.; FRANCO, OCTÁVIO L.; DIAS, SIMONI C.; CUNHA, NICOLAU B.

    Resumo em Inglês:

    Abstract The constant demand for new antibiotic drugs has driven efforts by the scientific community to prospect for peptides with a broad spectrum of action. In this context, antimicrobial peptides (AMPs) have acquired great scientific importance in recent years due to their ability to possess antimicrobial and immunomodulatory activity. In the last two decades, plants have attracted the interest of the scientific community and industry as regards their potential as biofactories of heterologous proteins. One of the most promising approaches is the use of viral vectors to maximize the transient expression of drugs in the leaves of the plant Nicotiana benthamiana. Recently, the MagnifectionTM expression system was launched. This sophisticated commercial platform allows the assembly of the viral particle in leaf cells and the systemic spread of heterologous protein biosynthesis in green tissues caused by Agrobacterium tumefaciens “gene delivery method”. The system also presents increased gene expression levels mediated by potent viral expression machinery. These characteristics allow the mass recovery of heterologous proteins in the leaves of N. benthamiana in 8 to 10 days. This system was highly efficient for the synthesis of different classes of pharmacological proteins and contains enormous potential for the rapid and abundant biosynthesis of AMPs.
  • Extremum Seeking-based Adaptive PID Control applied to Neuromuscular Electrical Stimulation Engineering Sciences

    ROUX-OLIVEIRA, TIAGO; COSTA, LUIZ R.; PINO, ALEXANDRE V.; PAZ, PAULO

    Resumo em Inglês:

    Abstract A multivariable deterministic extremum seeking (ES) is being evaluated to construct an adaptive Proportional-Integral-Derivative (PID) control law for the functional Neuromuscular Electrical Stimulation (NMES) of stroke patients. The developed scheme is applied to control the position of the patient’s arm so that movements of flexion/extension for its elbow can be produced. The true limitations of a PID controller for these types of applications is that a PID controller is designed for linear systems, but the system which is being controlled is nonlinear. Moreover, it is worth mention that clinicians’ knowledge of control systems is limited. Therefore, their expertise in tuning controllers is limited. Also, in NMES applications each patient is unique and requires a unique set of PID parameters. Since it can be time consuming and difficult to find proper parameters for each patient, a better procedure, or a more intelligent adaptive controller, is needed. The PID parameters are updated by means of ES in order to minimize a cost function which brings the desired performance attributes. Experiments are performed with healthy volunteers and stroke patients, including significant advances based on real data and validation. Quantitative results show a reduction of 64:1% in terms of RMSE (Root-Mean-Square Error) – from 8:94º to 3:21º – when comparing the tracking curves of the last cycle to the first cycle in the experiments with all stroke patients.
  • Counteracting the contemporaneous proliferation of digital forgeries and fake news Engineering Sciences

    FERREIRA, ALEXANDRE; CARVALHO, TIAGO; ANDALÓ, FERNANDA; ROCHA, ANDERSON

    Resumo em Inglês:

    Abstract Fake news has been certainly the expression of the moment: from political round table discussions to newspapers to social and mainstream media. It is everywhere. With such an intense discussion and yet few effective ways to combat it, what can be done? Providing methods to fight back even the least harming hoax is a social responsibility. To look for authenticity in a wide sea of fake news, every detail is a lead. Image appearance and semantic content of text and images are some of the main properties, which can be analyzed to reveal even the slightest lie. In this vein, this work overviews some recent methods applicable to the verification of dubious content in text and images, and discusses how we can put them together as an option to curb away the proliferation of unverified and phony “facts”. We briefly present the main idea behind each method, highlighting real situations where they can be applied and discussing expected results. Ultimately, we show how new research areas are working to seamlessly stitch together all these methods so as to provide a unified analysis and to establish the synchronization in space and time — the X-Coherence of heterogeneous sources of information documenting real-world events.
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