RESUMO

Aquatic macroinvertebrate fauna is a relevant component of limnic continental aquatic ecosystems, playing an important role in several processes with relevant biocomplexity. The present study characterized the benthic macroinvertebrate fauna found in three hydric bodies in the Sinos river drainage basin regarding community structure. Sample was collected from January to December 2013 in three locations in the basin: the city of Caraá (29 °4545.5S/50°1937.3W), the city of Rolante (29°3834.4S/50°3233.2W) and the city of Igrejinha (29°3610.84S/50°4849.3W). Abiotic components (pH, dissolved oxygen and temperature) were registered and collected samples were identified up to family type. Average annual pH, dissolved oxygen and temperature were similar in all locations. A total of 26,170 samples were collected. Class Insecta (Arthropods) represented 85.5% of total sample. Platyhelmintes, Mollusca and Annelida samples were also registered. A total of 57 families were identified for the drainage basin and estimators (Chao-1, Chao-2 and jackknife 2) estimated richness varying from 60 to 72 families.(AU)

A fauna de macroinvertebrados aquáticos é um relevante componente dos ecossistemas aquáticos límnicos continentais, atuando em vários processos de importante biocomplexidade. O presente estudo caracterizou a fauna de macroinvertebrados bentônicos em três corpos hídricos da Bacia Hidrográfica do Rio dos Sinos, em relação a estrutura da comunidade. Amostragens foram realizadas de janeiro a dezembro de 2013 em três locais na bacia: Município de Caraá (29°4545,5S/50°1937,3W), Município de Rolante(29°3834,4S/50°3233,2W) e Município de Igrejinha(29°3610,84S/50°4849,3W). Variáveis abióticas (pH, oxigênio dissolvido e temperatura) foram registradas e os exemplares coletados identificados até família. As médias anuais de pH, oxigênio dissolvido e temperatura foram similares em todos os pontos. Um total de 26.170 exemplares foi amostrado. A Classe Insecta (Arthropoda) representou 85,5% do total. Platyhelmintes, Mollusca e Annelida também foram registrados. Foram determinadas 57 famílias para a bacia hidrográfica e os estimadores (Chao-1, Chao-2 e jackknife 2) projetaram uma riqueza variando de 60 a 72.(AU)

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Abstract Aquatic macroinvertebrate fauna is a relevant component of limnic continental aquatic ecosystems, playing an important role in several processes with relevant biocomplexity. The present study characterized the benthic macroinvertebrate fauna found in three hydric bodies in the Sinos river drainage basin regarding community structure. Sample was collected from January to December 2013 in three locations in the basin: the city of Caraá (29 °45’45.5”S/50°19’37.3”W), the city of Rolante (29°38’34.4”S/50°32’33.2”W) and the city of Igrejinha (29°36’10.84”S/50°48’49.3”W). Abiotic components (pH, dissolved oxygen and temperature) were registered and collected samples were identified up to family type. Average annual pH, dissolved oxygen and temperature were similar in all locations. A total of 26,170 samples were collected. Class Insecta (Arthropods) represented 85.5% of total sample. Platyhelmintes, Mollusca and Annelida samples were also registered. A total of 57 families were identified for the drainage basin and estimators (Chao-1, Chao-2 and jackknife 2) estimated richness varying from 60 to 72 families.

Resumo A fauna de macroinvertebrados aquáticos é um relevante componente dos ecossistemas aquáticos límnicos continentais, atuando em vários processos de importante biocomplexidade. O presente estudo caracterizou a fauna de macroinvertebrados bentônicos em três corpos hídricos da Bacia Hidrográfica do Rio dos Sinos, em relação a estrutura da comunidade. Amostragens foram realizadas de janeiro a dezembro de 2013 em três locais na bacia: Município de Caraá (29°45’45,5”S/50°19’37,3”W), Município de Rolante(29°38’34,4”S/50°32’33,2”W) e Município de Igrejinha(29°36’10,84”S/50°48’49,3”W). Variáveis abióticas (pH, oxigênio dissolvido e temperatura) foram registradas e os exemplares coletados identificados até família. As médias anuais de pH, oxigênio dissolvido e temperatura foram similares em todos os pontos. Um total de 26.170 exemplares foi amostrado. A Classe Insecta (Arthropoda) representou 85,5% do total. Platyhelmintes, Mollusca e Annelida também foram registrados. Foram determinadas 57 famílias para a bacia hidrográfica e os estimadores (Chao-1, Chao-2 e jackknife 2) projetaram uma riqueza variando de 60 a 72.

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RESUMO

Aquatic macroinvertebrate fauna is a relevant component of limnic continental aquatic ecosystems, playing an important role in several processes with relevant biocomplexity. The present study characterized the benthic macroinvertebrate fauna found in three hydric bodies in the Sinos river drainage basin regarding community structure. Sample was collected from January to December 2013 in three locations in the basin: the city of Caraá (29 °45'45.5"S/50°19'37.3"W), the city of Rolante (29°38'34.4"S/50°32'33.2"W) and the city of Igrejinha (29°36'10.84"S/50°48'49.3"W). Abiotic components (pH, dissolved oxygen and temperature) were registered and collected samples were identified up to family type. Average annual pH, dissolved oxygen and temperature were similar in all locations. A total of 26,170 samples were collected. Class Insecta (Arthropods) represented 85.5% of total sample. Platyhelmintes, Mollusca and Annelida samples were also registered. A total of 57 families were identified for the drainage basin and estimators (Chao-1, Chao-2 and jackknife 2) estimated richness varying from 60 to 72 families.

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The spread of enteric viruses of domestic animals and human beings to wild species can be facilitated by the resistance of these viruses on the environment and their ability to be transmitted by water and contaminated food. The health status of the populations of pampas foxes Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) is largely unknown and the landscapes occupied by these animals in southern Brazil have been threatened by human occupation and expansion of agriculture. In this work, the search of genomes of human and canine adenoviruses in feces from these wild carnivores was used to track the dissemination of domestic animals and human pathogens to the free-living populations in a wildlife reserve located in southern Brazil. This was performed by virus-specific differential real-time polymerase chain reactions (qPCR) on stool specimens, avoiding capture and additional stress to the animals. Genus-specific conventional reverse-transcriptase PCR (RT-PCR) was complementarily performed aiming the detection of enteroviruses (EV) and rotaviruses (RV) on these same samples. HAdV genomes were found on 14 out of the 17 (82.35%) stool samples analysed, whereas CAV was found co-infecting 5 of these samples. RV genomes were detected on 7 of the 17 samples (41.18%) and all samples were negative for EV. The results point to the dispersion of HAdV and RV at a high rate to these species of South American wild carnivores, which can be an effect of growing anthropisation of the habitat of these animals.

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The spread of enteric viruses of domestic animals and human beings to wild species can be facilitated by the resistance of these viruses on the environment and their ability to be transmitted by water and contaminated food. The health status of the populations of pampas foxes (Lycalopex gymnocercus) and crab-eating foxes (Cerdocyon thous) is largely unknown and the landscapes occupied by these animals in southern Brazil have been threatened by human occupation and expansion of agriculture. In this work, the search of genomes of human and canine adenoviruses in feces from these wild carnivores was used to track the dissemination of domestic animals and human pathogens to the free-living populations in a wildlife reserve located in southern Brazil. This was performed by virus-specific differential real-time polymerase chain reactions (qPCR) on stool specimens, avoiding capture and additional stress to the animals. Genus-specific conventional reverse-transcriptase PCR (RT-PCR) was complementarily performed aiming the detection of enteroviruses (EV) and rotaviruses (RV) on these same samples. HAdV genomes were found on 14 out of the 17 (82.35%) stool samples analysed, whereas CAV was found co-infecting 5 of these samples. RV genomes were detected on 7 of the 17 samples (41.18%) and all samples were negative for EV. The results point to the dispersion of HAdV and RV at a high rate to these species of South American wild carnivores, which can be an effect of growing anthropisation of the habitat of these animals.(AU)

A disseminação de vírus entéricos de animais domésticos e seres humanos para espécies selvagens pode ser facilitada pela resistência desses vírus no ambiente e sua capacidade de ser transmitida por água e alimentos contaminados. O estado de saúde das populações de Graxains-do-campo (Lycalopex gymnocercus) e Cachorros-do-mato (Cerdocyon thous) é em grande parte desconhecida e as paisagens ocupadas por estes animais no sul do Brasil têm sido ameaçadas pela ocupação humana e a expansão da agricultura. Neste trabalho, utilizou-se a pesquisa de genomas de adenovírus humanos (HAdV ) e caninos (CAV-1 e -2) em amostras fezes desses carnívoros selvagens com vistas a diagnosticar a disseminação de patógenos de animais domésticos e seres humanos às populações de vida livre em uma reserva de vida selvagem, localizado no sul do Brasil. Foram realizadas reações em cadeia da polimerase diferenciais e em tempo real (qPCR) de adenovírus específicos em amostras de fezes, evitando a captura e estresse adicional para os animais. PCRs gênero-específicas convencionais com transcrição reversa prévia (RT-PCR) foram ainda realizadas visando a detecção de enterovírus (EV) e rotavírus (RV) nestas mesmas amostras. Genomas de HAdV foram encontrados em 14 a 17 amostras de fezes (82.35%) analisados, Considerando que o CAV foi encontrado coinfectando 5 destas amostras. Genomas de RV foram detectados em 7 das 17 amostras (41.18%) e todas as amostras foram negativas para EV. Os resultados apontam para a dispersão de HAdV e RV em uma taxa elevada para estas espécies de carnívoros selvagens sul-americanas, que podem ser um efeito da crescente antropização do habitat desses animais.(AU)

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Research on microbiota in cattle tick and the evaluation of its activity against other microorganisms can contribute to identify new molecules potentially useful to control infections caused by bacteria and protozoa. Biofilms pose increasing problems worldwide, mainly due to their resistance to antimicrobial therapies and host immune response. In this study we investigate the ability Rhipicephalus (Boophilus) microplus-associated bacteria may exhibit to produce anti-biofilm and trichomonicidal compounds. Gut, ovary, salivary glands, and Gené organ were collected from engorged R. microplus female. Homogenates of each tissue were inoculated onto 15 distinct culture media. Anti-biofilm and trichomonicidal activities were analyzed by culturing each bacterium isolated in a liquid medium. Results showed that R. microplus cattle tick microflora varies for different tissues. Bacteria belonging to different genera (Aeromonas, Bacillus, Brevibacillus, Castelaniella, Comamonas, Kocuria, and Microbacterium) were identified. Interestingly, all bacterial species found displayed pronounced activity against Staphylococcus epidermidis and Pseudomonas aeruginosa biofilms, and also against the cattle pathogen Tritrichomonas foetus, confirming the hypothesis that cattle tick could be a source of bacteria active against pathogens. This is the first study showing that bacteria isolated from a tick exert anti-biofilm and trichomonicidal activities.

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We subtyped Brazilian Yersinia pestis strains by pulsed-field gel electrophoresis (PFGE). This was done with 22 Brazilian Y. pestis strains: 17 from an outbreak and 5 from endemic routine surveillance. The strains were divided into 2 groups (I and II), 8 subgroups (A-H) and 19 PFGE profiles or pulsotypes. PFGE did not separate outbreak from non-outbreak strains, as identical pulsotype patterns were found among outbreak strains and strains obtained from surveillance. However, it was able to detect intraspecific genetic diversity among Brazilian strains. This PFGE technique was able to differentiate a homogeneous group of Brazilian Y. pestis strains.

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Plague outbreaks are occasionally reported in Brazil. Unfortunately, due to great genetic similarity, molecular subtyping of Yersinia pestis strains is difficult. Analysis of multiple-locus variable number of tandem repeats (VNTR), also known as MLVA, has been found to be a valuable tool to discriminate among strains. To check for genetic differences, strains obtained from two different ecological complexes in Brazil collected during two different epidemiological events, an epizootic in Sítio Alagoinha in 1967 and an outbreak in Planalto da Borborema in 1986, were subtyped through MLVA using 12 VNTR loci. Three clusters (A, B and C) were observed. Of the 20 strains from the epizootic, 18 fit into cluster A. Cluster A was divided into two subgroups: A(1) (15 strains) and A(2) (3 strains). Of the 17 strains from the outbreak, 15 fit into cluster B. Cluster B was divided into three subgroups: B(1) (4 strains), B(2) (4 strains) and B(3) (7 strains). Cluster C is a singleton with one epizootic strain. The external standards, Y. pestis CO92 and Y. pseudotuberculosis IP32953, formed two clusters of singletons. The stability of 12 VNTR loci of three unrelated cultures included in this study was assessed. The 12 VNTR loci were stable through multiple serial subcultures in the laboratory. MLVA revealed that Y. pestis populations in Brazil are not monomorphic, and that there is intraspecific genetic diversity among Brazilian plague strains. We conclude that there is some correlation among genetic groups of this species, related to the temporal and geographic origin of isolates.

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In this paper, the multifaceted Cr(VI) toxicity over the freshwater green alga Monoraphidium convolutum was assessed by concomitantly monitoring thiol-dependent redox balances, photosynthesis activity and growth-survival scores. Control group showed exponential growth rate at (5.78±0.29) division/day until 8th day with linear increasing chlorophyll a/protein ratios (CHLa/PROT) throughout the period. Cultures of M. convolutum were exposed for 5 days to Cr(VI) concentrations from 0 up to 100mg/L showing that CHLa/PROT ratios were sensibly affected, in agreement to the calculated LC(50,48 h) (5.38±0.72) mg/L from the concentration-response curve of cell mortality after 48 h. Regarding photosynthesis effects, Cr(VI) concentrations >1.0 mg/L showed significant increases in short-term (after 2 h) electron transfer rates (ETR) and quantum yields of photosystem II (Φ(PSII)), followed by subsequent decline of both parameters after 48 and 72 h. Biochemical analyses showed that maximal GSH concentrations in algal cultures were observed upon 1mg Cr(VI)/L and higher dichromate concentrations dramatically increased the activity of antioxidant GSH-dependent enzymes ascorbate peroxidase and glutathione reductase. However, no variation was observed in the cellular GSH levels, whereas GSSG and lipid peroxidation indexes abruptly increased upon 10 mg Cr(VI)/L exposure. Altogether, plant physiology, photosynthesis and biochemical data suggest that the GSH-dependent antioxidant system is capable to sustain M. convolutum viability through efficient photosynthesis activity and adequate antioxidant responses up to Cr(VI) concentrations of 1.0mg/L, when redox unbalances were first evidenced.

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The aim of the present work was to evaluate whether the treatment of human neutrophils with phenanthrene (PHN) can alter the phagocytic and microbicidal capacity of these cells by causing a disruption in redox balance. Peripheral neutrophils from healthy subjects were treated for up to 24 h with increasing concentrations of phenanthrene. Phagocytic/microbicidal activities, antioxidant enzymes, oxidative lesions (thiobarbituric acid-reactive substances and protein thiol and carbonyl groups) and redox signaling compounds (intracellular Ca(2+), superoxide, hydrogen peroxide and nitric oxide) were monitored on neutrophils exposed to 10 microg PHN ml(-1). Cell viability decreased abruptly at PHN concentrations above 10 microg ml(-1) (LC50 = 20.86 +/- 0.51 microg ml(-1) and p-sigmoidal slope = 19.88 +/- 10.11). Phagocytic and microbicidal capacities were decreased by 60 and 82%, respectively. Substantial increases in total-/Mn-SOD, catalase, glutathione peroxidase and glutathione reductase activities (by 61, 15, 87, 245 and 70%, respectively) matched the oxidative injury obtained in TBARS (2.5-fold higher) and protein thiol (54% lower). Diminished productions of superoxide by 18% and hydrogen peroxide by 29% were observed in association to exacerbated calcium (27%) and nitric oxide (63%) levels. The data indicate that phenanthrene might be associated with substantial reduction in human neutrophil functions due to severe intracellular redox imbalances.

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We compared the avifauna recorded in a recent survey in an urban park (Parque Municipal Henrique Luís Roessler, Parcão) and surroundings, Novo Hamburgo, RS, with past data, to evaluate the possible alterations in species composition over time. Of the 265 species compiled as original elements of that region, 114 were found at Parcão. Among forest species, 37% were considered locally extinct. The most affected guild was the large frugivores, with nine extinct species and one survivor (Trogon surrucura). Birds highly sensitive to disturbance as well as endemic species were the most extinguished. The possible causes for this loss are fragmentation, hunting and environmental changes. The diversity today is threatened, thus conservation measures are necessary in that region. The most important actions are: maintenance of ecological corridors, protection of natural remnant areas and the establishment of protected areas.

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A new device to sample freshwater benthic macroinvertebrates was used in a low and sandy stretch of a Brazilian sub-tropical river (the River Cai, Triunfo, RS) and in one of its small tributaries, Bom Jardim brook (Arroio Bom Jardim). In this study, the effectiveness of this device, a PET sampler, was tested at different sites in the river and the brook throughout the four seasons between 2001-2002. Comparisons were made by PCA and ANOVA, both employing a bootstrap procedure based on similarity matrices. The PET sampler proved to be a reliable tool for detection of seasonal and spatial differences in richness, total abundance of organisms, and Shannon's diversity index in both river and brook and is therefore recommended for use in the monitoring of macroinvertebrate communities in this system.

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Foi utilizado novo dispositivo para amostragem de macroinvertebrados bênticos de água doce num segmento do curso inferior arenoso de um rio brasileiro subtropical (Rio Caí, Triunfo, RS) e de seu pequeno tributário, Arroio Bom Jardim. Neste estudo, a efetividade do amostrador PET foi testada em locais diferentes do rio e do arroio e ao longo das quatro estações do ano, entre 2001-2002. Foram realizadas comparações por PCA e ANOVA, ambos empregando um procedimento "bootstrap" com base em matrizes de similaridade. O amostrador PET é confiável para detecção de diferenças sazonais e espaciais de riqueza, abundância total de organismos e diversidade de Shannon no rio e no arroio, sendo, portanto, recomendável para o monitoramento de comunidades de macroinvertebrados nesse sistema.

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Several lines of investigation have suggested an interplay between bioluminescence (BL) and oxyradical metabolism, mainly in bacteria and beetles. Although not yet confirmed, luminescent beetles seem to be challenged daily by oxidative conditions imposed by higher oxygen absorption necessary to enhance light emission for courtship (adult lampyrids and elaterids) and prey attraction (e.g. Pyrearinus termitilluminans larvae). This work reports the activities of luciferase, superoxide dismutase (SOD), catalase and dehydroascorbate reductase (DHAR) and total glutathione content at different times of the day in the bright prothorax and dim abdomen of larval Pyrearinus termitilluminans (Coleoptera: Elateridae), investigating a possible adjuvant role for luciferase in oxygen detoxification. Luciferase activity in the prothorax was shown to peak at 7 p.m., which is the time when P. termitilluminans larvae light up for prey attraction. In their habitat, P. termitilluminans larvae emit light until 8.30 p.m. However, at 8 p.m., prothorax luciferase activity achieved basal levels and total glutathione content declined to the daily lowest value, possibly resulting from hyperoxidative conditions during this time. Significant increases in the activities of total SOD (28%) and catalase (37%) were observed in the prothorax at 9 p.m., which should minimize the extent of damage from this potentially hazardous period. Prothorax total SOD (42% higher than daily average) and abdomen CuZnSOD (41%) and catalase (95%) activities showed extra peaks at 7-10 a.m., and abdomen DHAR activity was maximal (37%) earlier (4-7 a.m.). These morning increases in antioxidant enzyme activities may be associated with biological events other than bioluminescence, e.g. intense physical activity for digging tunnels and/or digestion of captured preys. These data suggest that oxyradical pathway and bioluminescence are coordinated, especially in the prothorax, to minimize the oxidative stress imposed by higher irrigation of the photocytes with O(2) when P. termitilluminans larvae emit light.

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Insects show unique adaptations to cope with oxidative challenges during larval development, metamorphosis and adulthood. Our previous findings suggested that bioluminescence may act as an auxiliary oxygen-detoxifying mechanism in larvae of Pyrearinus termitilluminans (Elateridae: Coleoptera). We now study the antioxidant status in larval P. termitilluminans, evaluated in terms of levels of chemical and enzymatic antioxidant defenses, as compared to luciferase activity in the prothorax (intensely bright) and abdomen (dim) of the larvae, during natural- and 20-hydroxyecdysone (20-HE)-induced development. In the prothorax, relative total SOD activities in small (< 1 cm), medium (1-2 cm) and large (> 2 cm) larvae were 1.00:0.53:0.32. Catalase activity also decreased with development (1.00:0.69:0.55). In contrast, prothorax luciferase activities and urate content increased with ratios of 1.0:2.2:2.5 and 1:15:97, respectively. No increases were found in the level of prothorax lipid and protein oxidation. In the abdomen, luciferase activity decreased markedly with development (1.00:0.33:0.17), as did other antioxidant enzymes, including dehydroascorbate reductase (1.00:0.59:0.17) and levels of lipid peroxidation products and protein carbonyls. Similar variations were observed in antioxidant enzyme activities when the larvae were treated with 20-HE, except for prothorax catalase. As observed in natural larval growth, luciferase activity was augmented (two-fold in prothorax) upon steroid treatment, and the levels of thiobarbituric acid-reactive substances were magnified in both segments. The increase of luciferase activity and a higher urate content in the prothorax during larval development may reflect metabolic adaptations to keep levels of oxyradicals low in order to compensate for decreased antioxidant enzyme activities.

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Accumulation of 5-aminolevulinic acid (ALA) is an event characteristic of porphyrias that may contribute to their pathological manifestations. To investigate effects of ALA independent of porphyrin accumulation we treated rats with the methyl ester of succinylacetone, an inhibitor of 5-aminolevulinic acid dehydratase that accumulates in the porphyric-like syndrome hereditary tyrosinemia. Acute 2-day treatment of fasted rats with succinylacetone methyl ester (SAME) promoted a 27% increase in plasma ALA. This increase in plasma ALA was accompanied by augmentation of the level of total nonheme iron in liver (37%) and brain (20%). Mobilization of iron was also indicated by 49% increase in plasma iron and a 77% increase in plasma transferrin saturation. Liver responded with a mild (12%) increase in ferritin. Under these acute conditions, some indications of oxidative stress were evident: a 15% increase in liver reactive protein carbonyls, and a 42% increase in brain subcellular membrane TBARS. Brain also showed a 44% increase in CuZnSOD activity, consistent with observations in treatment with ALA. Overall, the data indicate that SAME promotes ALA-driven changes in iron metabolism that could lead to increased production of free radicals. The findings support other evidence that accumulation of ALA in porphyrias and hereditary tyrosinemia may induce iron-dependent biological damage that contributes to neuropathy and hepatoma.

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This work examines the hypothesis that beetle bioluminescent reactions may primarily have evolved to provide an auxiliary O2 detoxifying mechanism. The activities of antioxidant enzymes and of luciferase in the prothorax (bright) and abdomen (dim) of luminous larval Pyrearinus termitilluminans (Coleoptera: Elateridae) were measured after previous challenge with either hyperoxia, hypoxia, or the firefly luciferase inhibitor luciferin 6'-methyl ether (LME). Upon exposure to pure O2 for 72 h, the prothorax activities of total superoxide dismutase (SOD) and catalase were found to increase by 85% and 50%, respectively. Concomitantly, levels of luciferase and luciferin increased 80% and 50%. Assays of thiobarbituric acid reactive substances (TBARS) showed significantly augmented lipid peroxidation only in the abdomen (30%) where levels of antioxidant enzymes and especially luciferase are low. In contrast, exposure to hypoxia (2% O2) led to significant increases in prothorax citrate synthase (85%), succinate dehydrogenase (25%), and lactate dehydrogenase (30%) activities, but not in luciferase or antioxidant enzyme levels. LME administration alone decreased luciferase activities 20% but did not alter prothorax SOD activity. Prothorax SOD activity was increased by concomitant LME and hyperoxia treatments (30%), along with higher levels of TBARS (25%) and protein reactive carbonyl groups (50%). Altogether these data suggest that in elaterids, bioluminescence and reactions catalyzed by antioxidant enzymes may cooperate to minimize oxidative stress.

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