745 resultados para CNPQ::CIENCIAS BIOLOGICAS::ECOLOGIA::ECOLOGIA DE ECOSSISTEMAS


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Brazil is among the largest cashew nut producers of the world. However, the roasting process is still carried out artisanally, especially in the Brazilian semiarid region. In face of this occupational problem, the aim of this study was to perform a physical-chemical characterization of the particulate matter (PM) emitted by the roasting of cashew nuts, as well as to determine the occupational risk and molecular mechanisms associated. The most evident PM characteristics were the prevalence of fine particles, typical biomass burning morphologies such as tar ball and the presence of the elements K, Cl, S, Ca and Fe. In addition, atmospheric modeling analyses suggest that these particles can reach neighboring regions of the emission source. Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic potential, such as benzo[a]pyrene, dibenz[a,h]anthracene, benzo[a]anthracene, benzo[b]fluoranthene, chrysene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and benzo[j]fluoranthene were the most abundant PAHs found in the two air monitoring campaigns. Among the identified oxy-PAH the benzanthrone (7H-benz[d,e]anthracen-7-one) had the highest concentration and the evaluation of lifetime cancer risk showed an increase of 12 to 37 cases of cancer for every 10,000 exposed people. Chemical analysis of roasted cashew nuts identified the PAHs: phenanthrene, benzo[g,h,i]perylene, pyrene and benzo[a]pyrene, besides the 3-pentadecilfenol allergen (urushiol analogue) as prevalent. Occupational exposure to PAHs was confirmed by the increase of urinary 1-hydroxypyrene levels and genotoxic effects were evidenced by the increase on micronuclei and nuclear bud frequency in exfoliated buccal mucosa cells among the exposed workers. Other biomarkers of effects such as karyorrhexis, pyknotic, karyolytic, condensed chromatin and binucleated cells also have their frequencies increased when compared to an unexposed control group. The investigation of the molecular mechanisms associated with the PM organic extract showed cytotoxicity in human lung cell lines (A549) at concentrations ≥ 4 nM BaPeq. Using non-cytotoxic doses the extract was able to activate proteins involved in the DNA damage response pathway (Chk1 and p53). Moreover, the specific contribution of the four most representative PAHs in the cashew nut roasting sample showed that benzo[a]pyrene was the most efficient to activate Chk1 and p53. Finally, the organic extract was able to increase persistently the mRNA expression involved in the PAHs metabolism (CYP1A1 and CYP1B1), inflammatory response (IL-8 and TNF-α) and cell cycle arrest (CDKN1A) for DNA repair (DDB2). The high PM concentrations and its biological effects associated warn of the serious harmful effects of artisanal cashew nut roasting and urgent actions should be taken to the sustainable development of this activity.

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Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

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Fucoidan is a term used to define heteropolysaccharides that are composed of less than 90% L-fucose. The exception to this rule is the homofucoidan obtained from the seaweed Fucus vesiculosus. This fucoidan can be purchased from SIGMA Co. and have been used in various research for evaluation of their pharmacological activities. However, it is not a pure molecule. In fact, it is a mix of several fucoidan molecules. In this work, were obtained, from acetone precipitation, and biochemically characterized, four fucoidan molecules from SIGMA-ALDRICH Co. fucoidan to evaluate their anticoagulant, antioxidant, antiadipogenic, immunomodulatory and antiurolithiatic activities. In anticoagulant activity, evaluated by aPTT assay, fucoidans F0.9, F1.1 and F2.0 increased eightfold the coagulation time, compared to the control, when a mass of 10 μg was used. To PT test, only fucoidan F0.9 was capable of increase the coagulation time, compared to control. In the total antioxidant capacity assay (TAC), the fucoidan F2.0 showed 400 ascorbic acid equivalents, while fucoidan F0.5, the lest effective, 38 equivalents. In respect to the effect on pre-adipocyte cell lines (3T3-L1) adipogenesis, was observed that fucoidan F1.1 and F2.0 reduced the adipogenesis and this effect was associated to the reduction in the expression of regulatoy proteins C/EBPα, C/EBPβ and PPARγ. On the other hand, fucoidans F0.5 and F0.9 induced increased expression of these regulatory proteins. Furthermore, fucoidan F2.0 induced hydrolysis of triglycerides present in the interior of adipocytes. The immunomodulatory effect was evaluated and observed that the presence of fucoidans F0.5 , F1.1 and F2.0 significantly reduced the production of nitric oxide by activated macrophages with LPS specially fucoidan F2.0 that in 100 μg/mL, reduced about 55% the effect caused by LPS. Relative to the effect upon the formation of calcium oxalate crystals, fucoidan F0.5 was more effective in reduce the aggregation of the crystals and this effect it was not significantly different regarding the effect caused by the crude. Besides, fucoidan F0.5 only promoted the formation of COD type crystals, while fucoidans F1.1 and F2.0 did not influence the formation of crystals compared with the control. The results described in this study indicate that the commercial crude fucoidan of Fucus vesiculosus it’s a mix of several fucoidan which, in turn, have different chemical compositions besides having different pharmacological activities. The use of these fucoidans it´s indicated according the pharmacological activity to be evaluated.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.

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Leishmania infantum is the main etiologic agent of visceral leishmaniasis in the New World. The pattern of distribution of leishmaniasis has changed substantially and has presented an emerging profile within the periphery of the Large Urban Centers. Leishmania infection can compromise skin, mucosa and viscera. Only 10% of the individuals infected develop the disease and 90% of human infection is asymptomatic. The main factors involved in the development of the disease are the host immune response, the vector’s species and the parasite’s genetic content. The sequencing of Leishmania isolated seeks to increase the understanding of the symptoms of individuals. The aim of this study was to evaluate the genetic diversity of circulating Leishmania strains among humans, and symptomatic and asymptomatic, and dogs from endemic areas of Rio Grande do Norte State and analyze sandflies from endemic areas for cutaneous and visceral disease. The genetic variability was evaluated by the use of markers hsp70 , ITS1 and a whole genome sequencing was also carried out. The amplified hsp70 and ITS1 of samples were analyzed and assembled using a Phred / Phrap package. The dendograms were constructed using the same methodology, but adding 500 bootstraps, followed by inferences on the relationships between Leishmania variants. The sequences of the 20 Brazilian isolates were mapped to the reference genome L. infantum JPCM5, using the Bowtie2 program and the identification of 36 contigs. The information of the valid SNPs were used in the PCA. SNPs were visualized by Geneious 7.1 and IGV. The genome annotations were transferred to their respective chromosomes and displayed on Geneious. The matching sequences of all chromosomes were aligned using Mauve. The phylogenetic trees were calculated according to maximum likelihood and JTT models. Sandflies were analyzed by PCR for the identification of Leishmania infection, a blood meal source and GAPDH sand fly. As a result, hsp70 and ITS1 were not capable of identifying genetic variability among human isolates from symptomatic and asymptomatic, and dogs. The complete sequencing of the 20 Brazilian isolates revealed a strong similarity between the circulating Leishmania strains in Rio Grande do Norte. The isolates collected in the city of Natal from humans and canines remained grouped in all analyzes, suggesting that there is genotypic and geographic proximity among the isolates. The isolated samples in the 1990s had a higher genotypic diversity when compared to freshly isolated samples. All isolates presented 36 chromosomes with variable ploidy among them, no correlation was found between the number of amastina genes copies, gp63, A2 and SSG with such clinic forms. In general, we did not find correlation between symptomatic and asymptomatic clinical forms and the gene content of the Brazilian isolates of Leishmania. 34,28% of the sandflies collected in the upper west region were L. longipalpis and the main sources of blood meal were humans, dogs and chickens.

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Para processar a informação ambiental e perceber o tempo, os indivíduos utilizam-se de pistas ambientais, como luz e temperatura, que servem como guias para o relógio interno. O mecanismo temporizador endógeno é chamado relógio circadiano, o qual comanda uma grande variedade de ritmos diários bioquímicos, fisiológicos e comportamentais presentes nos organismos. Com isso, os animais podem antecipar eventos espaço-temporalmente distribuídos e usar essa informação para organizar as atividades diárias, o que é uma vantagem adaptativa para os indivíduos, já que muitos fatores ambientais apresentam variação circadiana. Aprendizagem espaço-temporal (do inglês: "time-place learning’’-TPL) é a habilidade de associar lugares com importantes eventos biológicos em diferentes horas do dia. Em nosso estudo utilizamos como modelo o peixe paulistinha (Danio rerio), conhecido por ser altamente social, para testar aprendizagem espaço-temporal baseada em reforço social. Além disso, objetivamos averiguar os efeitos das condições de claro constante e escuro constante na aprendizagem espaço-temporal, e se nessas condições, a atividade do peixe paulistinha é alterada. Para isso, testamos três diferentes condições (n=10): grupo claro-escuro (CE), grupo claro constante (CC) e grupo escuro constante (EE) durante 30 dias da seguinte maneira: diariamente, um grupo de 5 peixes paulistinha foi introduzido em um recipiente localizado no compartimento da manhã (um dos lados do aquário), às 8:00h e retirado às 9:00h, e em outro recipiente do compartimento da tarde (lado oposto do aquário), às 17:00h e removido às 18:00h, servindo como estímulo para que o peixe experimental ocupasse o compartimento onde o grupo fosse colocado. O comportamento foi filmado nos dois horários, 15 minutos antes e durante os 60 minutos de exposição ao estímulo, no 15º e no 30ª dia, porém neste último, os peixes foram filmados sem a presença do estímulo a fim de averiguarmos a aprendizagem espaço-temporal. Por fim, para saber a influência das três condições luminosas na atividade dos peixes, filmamos os últimos 6 dias de teste, para registrar o padrão de atividade. Nossos resultados mostraram que em ciclo claro-escuro (CE) o peixe paulistinha apresenta TPL, bem como é capaz de antecipar a hora e local do estímulo (grupo de coespecíficos), enfatizando a importância do estímulo social para a aprendizagem. Em condições de claro constante e escuro constante, o peixe paulistinha não apresentou aprendizagem espaço-temporal. Ademais, após 30 dias em condições luminosas constantes (claro constante e escuro constante), o peixe paulistinha mantém ritmo circadiano, porém em claro constante sua atividade é aumentada e seu ritmo atividade-repouso é alterado, através de um padrão de atividade distribuída homogeneamente ao longo das 24h, ao invés de concentrada na subjetiva fase clara, como nos grupos de ciclo claro-escuro e escuro constante, os quais conservam o padrão de atividade diurno da espécie.

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In recent years we have observed, in Brazil, the expansion of democratic spaces, providing the use of participatory management strategies in common-pool areas. However, the existence of a co-management model does not guarantee its practice, neither that it will prevent the depletion of common features characterizing the tragedy proposed by Hardin. In this work we analysed the management of Acaú-Goiana RESEX which is located in the cities of Acaú (PB) and Goiana (PE), eight years after its legal creation. We evaluated how much the users of RESEX possess information (even if non formalized) regarding the common use of area and whether they exhibit collectivist values. We used as an interpretative tool the facilitators principles of common resource management (PGRC) identified by Elinor Ostrom and the questionnaire of human values proposed by Schwartz. The human values questionnaire was applied to 240 individuals, half beneficiary and the other half non-beneficiary, only the beneficiaries were submitted to the questionnaire of PGRC. Interviews were conducted in the period of May to September 2014. We tested three hypotheses: 1) The degree of dependence from RESEX resources will play an important role on indirect knowledge of the PGRC; 2) the inclusion of individuals in a communal area (RESEX) increases collectivists values; 3) higher collectivist value rates increases knowledge of PGRC. To this end, we defined levels of socio-economic dependence of RESEX resources, knowledge of PGRC and individual values. GLM statistic analysis of mean comparison and correlation were employed. Our results showed that the knowledge on six of the seven items analyzed in the basic principles (PGRC) is still low. The extended land area and the high number of users may be exerting a detrimental effect on the development of a co-management. Contrary to expected, it was not the dependency who influenced knowledge on the PGRC, but the time spent in contact with the RESEX. This indicates that direct contact with the environment, not the dependence of it, that raises awareness about PGRC. According to our hypothesis, individuals with collectivist values showed greater knowledge of PGRC and reduced hours of work within the RESEX, indicating a greater tendency of individuals refrain their use of the common resource. Individualistic values correlated with less knowledge of a PGRC. Among the beneficiaries, individuals with higher individualistic values had higher monthly income, while among non-beneficiaries there was no such correlation, demonstrating the economic advantages of individualism (free-riding) in situations of non-private use of resources. Our data emphasize the importance of guiding the main actors in the development of a co-participatory management in the direction of the basic principles, and to develop collectivist values among users of a common good can raise awareness of these principles.

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Inflammation is combined of a vascular and a cellular reaction, resulting in different cells and tissue responses, both the intravascular and extravascular environment. As the inflammatory process occurs, coagulation proteases, in particular thrombin (FIIa), are able to initiate various cellular responses in vascular biology and therefore is often observed activation of other biological systems, leading to complications during an event inflammatory, such as thrombosis and angiogenesis. Thus, antagonists molecules of these events are interesting models for the development of novel anti-inflammatory drugs. Thereby, it is worth stressing the glycosaminoglycans (GAGs), which are able to interact with several proteins involved in important biological processes, including inflammation and coagulation. Therefore, this study aimed to evaluate the anti-inflammatory, antithrombotic and anti-angiogenic potentials, as well anticoagulant of a dermatan sulfate-like GAG (DS) extracted from the Litopenaeus vannamei cephalotorax. The compound was obtained after proteolysis and purification by ion-exchange chromatography. After total digestion by DS-like compounds digesting lyases (chondroitinase ABC), the DS-like nature was revealed, and then called DSL. The shrimp compound showed reduced anticoagulant effect by the aPTT assay, but high anti-IIa activity, directly and through heparin cofactor II. On inflammation, the compound had a significant inhibitory effect with the reduction of proinflammatory cytokines. Potential Inhibitory were reported in the antithrombotic and anti-angiogenic assay, the latter being dose dependent. As for anti-hemostatic activity, the polysaccharides did not induced significant bleeding effect. Thus, the results shown by the shrimp DS-like compound indicate this glycosaminoglycan as a biotechnology target with prospects for the development of new multipotent drugs.

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In general, men and women look for characteristics that can indicate improvement of their reproductive success in their romantic partners. However, partner choice is not only based on what the individual want in a partner, but he/she also takes into consideration how they perceive themselves in a determined environment, in a way that self-perception can change according to the context where the individual is inserted in. Besides the environment, self-esteem can be a factor that modifies romantic partner preferences and the way that people choose these partners for being able to influence how people evaluate themselves. Most of the studies that originate today’s universal standards in the study of romantic partner were conducted with undergraduate students, which may limit the coverage of the conclusions for contemplating people of the same educational level and probably also socioeconomic status (SES). The present research, held in Brazil, where the social inequality rate is high, and part in Canada, country with low social inequality, had as goal verifying romantic partners preferences and choices and self-evaluation as romantic partners in different educational level and SES. Men, mainly of low SES, tend to prioritize social status when looking for a romantic partner while the universal pattern is the preference for physical attractiveness, and women of low SES seem to be aware of this preference when expressing that social status is important for their self-perception. In addition, the results corroborate the influence of the context, selfesteem, and SES in the self-perception as a romantic partner, though the latter two appear to modulate how the is the influence of the context on participants’ perception. Moreover, this research also indicated that the preferences appear to represent the choices for the most important characteristics for each sex, being the other characteristics probably modulated by the quantity of available participants in the environment.

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The fish, Hoplias malabaricus (Osteichthyes: Erythrinidae) and armored catfish, Hypostomus pusarum (Loricariidae) are of freshwater origin from the neotropical region, and are considered ecologically and economically of important. This work investigated the trophic strategies, the morphology and histology of the digestive tract of these fish captured from the Marechal Dutra reservoir, Acari, the semiarid region of Rio Grande do Norte, Brazil. A total of 133 individuals of H. malabaricus and 118 specimens of H. pusarum were analyzed. The two study species occupy different levels in the food chain and spatial distribution in the water column of the reservoir. The results of this study are presented in the form of four scientific papers. The first article describes the morphology and histology of the digestive tract and the feeding habits of H. malabaricus (Bloch, 1794). This fish has a short intestine, with an intestinal coefficient of 0.72 ± 0.09. The dietary importance index indicates that H. malabaricus feeds preferentially on animal matter, especially on fish (72.8%) and prawns (27.2%). The histology of its digestive tract confirms the carnivorous feeding habit. The second article discusses about the pioneering work on the feeding strategy and the characterization of anatomy and histology of the digestive tract of H. pusarum. The intestine of this fish is long, with an intestinal coefficient of 10.8±0.7. The dietary importance index indicates that H. pusarum feeds preferentially on organic matter in decomposition (88.7%) and on filamentous microalgae and diatoms (11.3%). The third article compares the morphological aspects of the digestive tract of H. malabaricus and H. pusarum, in relation to their food habits. The arrangement of the digestive organs in both species is directly related to the shape of the peritoneal cavity and the form of the body. The short intestine of H. malabaricus and the long intestine of H. pusarum are associated with their feeding habits. The morphology of the digestive tracts of H. malabaricus and H. pusarum confirm their food habits, carnivorous and detritivorous / herbivorous, respectively. The fourth article discusses the food and reproductive aspects (length and weight, length-weight relationship, type of growth and sex ratio) of H. pusarum. This species has a negatively allometric growth, with the predominance of females in the sampled population. H. malabaricus inhabits the pelagic environment and is a carnivore, while H. pusarum, lives in the benthic environment and is characterized as a detritivore/herbivore. Each species studied shows a very different diet, without trophic competition between them. The morphological and anatomical structures of the digestive tract reflect their feeding strategy.