Showing papers by "Universidade Federal Rural do Rio de Janeiro published in 2007"
TL;DR: In this article, the authors investigated the underlying mechanisms of SOM stabilization in Oxisols as affected by different crop rotations and tillage regimes at two sites in southern Brazil, and found that the greatest concentrations and differences in concentrations across tillage treatments were found in the fine (53-250μm) iPOM fractions occluded within microaggregates, especially when green manures are included in the rotation.
Abstract: It is well known that no-tillage (NT) practices can promote greater stocks of soil organic matter (SOM) in the soil surface layer compared to conventional tillage (CT) by enhancing the physical protection of aggregate-associated C in temperate soils. However, this link between tillage, aggregation and SOM is less well established for tropical soils, such as Oxisols. The objective of this study was to investigate the underlying mechanisms of SOM stabilization in Oxisols as affected by different crop rotations and tillage regimes at two sites in southern Brazil. Soils were sampled from two agricultural experiment sites (Passo Fundo and Londrina) in southern Brazil, with treatments comparing different crop rotations under NT and CT management, and a reference soil under native vegetation (NV). Free light fraction (LF) and intra-aggregate particulate organic matter (iPOM) were isolated from slaking-resistant aggregates. Of the total C associated with aggregates, 79–90% was found in the mineral fraction, but there were no differences between NT and CT. In contrast, tillage drastically decreased LF-C concentrations in the 0–5 cm depth layer at both sites. In the same depth layer of NT systems at Londrina, the concentrations of iPOM-C were greater when a legume cover crop was included in the rotation. At Londrina, the order of total iPOM-C levels was generally NV > NT > CT in the 0–5 cm depth interval, but the difference between NT and CT was much less than in Passo Fundo. At Passo Fundo, the greatest concentrations and differences in concentrations across tillage treatments were found in the fine (53–250 μm) iPOM fractions occluded within microaggregates. In conclusion, even though no aggregate hierarchy exists in these Oxisols, our results corroborate the concept of a stabilization of POM-C within microaggregates in no-tillage systems, especially when green manures are included in the rotation.
171 citations
TL;DR: Mexico stands out as a hotspot of parasite diversity for freshwater fishes, as does Brasil for marine fishes, however, among 57 marine fish species common to all 3 regions, populations from the Caribbean consistently harboured more parasite species.
Abstract: Although research on parasite biodiversity has intensified recently, there are signs that parasites remain an underestimated component of total biodiversity in many regions of the planet. To identify geographical hotspots of parasite diversity, we performed qualitative and quantitative analyses of the parasite-host associations in fishes from Latin America and the Caribbean, a region that includes known hotspots of plant and animal biodiversity. The database included 10 904 metazoan parasite-host associations involving 1660 fish species. The number of host species with at least 1 parasite record was less than 10% of the total known fish species in the majority of countries. Associations involving adult endoparasites in actinopterygian fish hosts dominated the database. Across the whole region, no significant difference in parasite species richness was detected between marine and freshwater fishes. As a rule, host body size and study effort (number of studies per fish species) were good predictors of parasite species richness. Some interesting patterns emerged when we included only the regions with highest fish species biodiversity and study effort (Brasil, Mexico and the Caribbean Islands). Independently of differences in study effort or host body sizes, Mexico stands out as a hotspot of parasite diversity for freshwater fishes, as does Brasil for marine fishes. However, among 57 marine fish species common to all 3 regions, populations from the Caribbean consistently harboured more parasite species. These differences may reflect true biological patterns, or regional discrepancies in study effort and local priorities for fish parasitology research.
158 citations
TL;DR: It is concluded that the acute decrease in serum T(4) and T(3) after INF is due to increased thyroid hormone catabolism from ectopic D3 expression in the heart, despite compensatory stimulation of the thyroid.
Abstract: In humans, there is a significant decrease in serum T(3) and increase in rT(3) at different time points after myocardial infarction, whereas serum TSH and T(4) remain unaltered We report here a time course study of pituitary-thyroid function and thyroid hormone metabolism in rats subjected to myocardial infarction by left coronary ligation (INF) INF- and sham-operated animals were followed by serial deiodination assays and thyroid function tests, just before, and 1, 4, 8, and 12 wk after surgery At 4 and 12 wk after INF, liver type 1 deiodinase activity was significantly lower, confirming tissue hypothyroidism Type 3 deiodinase (D3) activity was robustly induced 1 wk after INF only in the infarcted myocardium Reminiscent of the consumptive hypothyroidism observed in patients with large D3-expressing tumors, this induction of cardiac D3 activity was associated with a decrease in both serum T(4) ( approximately 50% decrease) and T(3) (37% decrease), despite compensatory stimulation of the thyroid Thyroid stimulation was documented by both hyperthyrotropinemia and radioiodine uptake Serum TSH increased by 43-fold in the first and 31-fold in the fourth weeks (P < 001), returning to the basal levels thereafter Thyroid sodium/iodide-symporter function increased 1 wk after INF, accompanying the increased serum TSH We conclude that the acute decrease in serum T(4) and T(3) after INF is due to increased thyroid hormone catabolism from ectopic D3 expression in the heart
136 citations
TL;DR: There was high variability in tolerance to UV-B radiation among the B. bassiana isolates, ranging from virtually zero tolerance to almost 80% tolerance; this will guide the selection of isolates for future arthropod microbial control experiments.
126 citations
TL;DR: Levels of metal contamination in gonads and muscles of three abundant fish species from different trophic levels indicate that human population should avoid to consume these fishes species from these segments of the Paraíba do Sul river.
Abstract: The Paraiba do Sul river is located in one of the most developed part of Brazil and receives many organic and industrial effluents directly affecting the ichthyofauna. Concentration of four heavy metals (Cu, Cr, Zn and Pb) were determined in two tissues (muscle and gonads) of three abundant fish species from different trophic levels (Oligosarcus hepsetus—carnivore, Geophagus brasiliensis—omnivore and Hypostomus luetkeni—detritivore) between November 2002 and April 2003. The aim was to test the hypothesis that the trophic level and the proximity from impacted areas influence levels of contamination and to assess if these species are indicators of large-scale habitat quality. Levels of heavy metals were detected by Total Reflection X-ray Fluorescence with Synchrotron Radiation (SR-TXRF) at the Brazilian National Synchrotron Radiation Laboratory (LNLS). Generally, gonads showed higher metal concentration than muscles, except for Cr. All examined metals, but Cu, exceeded the maximum permitted concentration (mpc) by the Brazilian legislation for human consumption in at least one tissue. O. hepsetus (carnivore) showed the highest contamination levels, followed by G. brasiliensis (omnivore) and H. luetkeni (detritivore). The middle-upper segment, which encompasses large urban areas, showed the highest levels of metal contamination in most cases. O. hepsetus showed the highest levels of contamination in muscles for Pb in the middle-upper river segment (7.98 ± 3.73; mpc = 2.0 μg g−1) and for Cr in the upper (5.53 ± 0.05; mpc = 0.10 μg g−1) and middle-upper (4.20 ± 0.85; mpc = 0.10 μg g−1) segments, which indicates that human population should avoid to consume these fishes species from these segments of the Paraiba do Sul river.
117 citations
TL;DR: The genetic characterization, sequencing and phylogenetic analysis of 18S rDNA sequences of Cryptosporidium isolates obtained from different animal hosts in Brazil constitute the first report of r DNA sequences from C. felis, C. canis and C. parvum isolated in Brazil.
89 citations
TL;DR: It is concluded that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal α-mannosidase by the alkaloid swainsonine.
Abstract: Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine.
86 citations
TL;DR: One hundred and seventy-six determined species and 39 undetermined species of copepods associated with 179 marine and freshwater fish species from Brazil are listed, including information about the site of infection, host habitat, localities and references.
Abstract: One hundred and seventy-six determined species and 39 undetermined species of copepods associated with 179 marine and freshwater fish species from Brazil are listed, including information about the site of infection, host habitat, localities and references. Also, a host-parasite list is included herein.
85 citations
TL;DR: Forage neutral detergent fiber value was higher at full sunlight than in the shade, while the crude protein content and in vitro dry matter digestibility were higher under the trees, therefore improving forage digestibility of grasses growing under trees.
Abstract: O objetivo deste trabalho foi avaliar caracteristicas morfofisiologicas e o valor nutritivo da Brachiaria decumbens, nas epocas chuvosas de 2003 e 2004, em um sistema silvipastoril, com faixas de 30 m de largura com essa graminea, alternadas com faixas de 10 m com arvores de Acacia mangium, A. angustissima, Mimosa artemisiana, Leucaena leucocephala x L. diversifolia, Eucalyptus grandis. Foi adotado o delineamento de blocos ao acaso, em parcelas subsubdivididas (caracteristicas morfofisiologicas) ou parcelas subdivididas (caracteristicas do valor nutritivo), com quatro repeticoes. Em 2003, o sombreamento foi de 65% da radiacao incidente fora do bosque e, em 2004, de 35%, depois da retirada de arvores de eucalipto. Sob sombreamento, a densidade de perfilhos, o indice de area foliar e a massa de forragem foram maiores no segundo ano. Os teores medios de fibra em detergente neutro (FDN) foram maiores a pleno sol que sob sombreamento, enquanto os valores medios de proteina bruta (PB) e a digestibilidade in vitro da materia seca foram maiores a sombra. O sombreamento moderado aumenta os teores de PB, reduz os teores de FDN e incrementa a digestibilidade da forragem de gramineas que crescem sob a copa das arvores.
82 citations
TL;DR: In this paper, single strength orange juice was concentrated by reverse osmosis in a plate and frame pilot plant with 0.72m 2 of filtration area, and three transmembrane pressures, 20, 40 and 60 bar, were evaluated and concentration factors of 2.3, 3.8 and 5.8 were obtained.
82 citations
TL;DR: Some organic matter fractions exhibited, besides promotion of lateral roots number, increase in the length of principal root, which is not a typical auxin effect, indicating that these substances could contain other physiologically active substances.
Abstract: The presence of ramified and abundant lateral roots is fundamental to plant growth on highly weathered soils In this work, the effects of humic acid (HA), fulvic acid and hexanic‐methanolic (HM) extract, after alkaline extraction from topsoil of seven different oxisols, on the development of roots of Arabidopsis thaliana was evaluated Furthermore, we used another emergent plant model, that is, micro-tom (MT) tomatoes with size similar to that of Arabidopsis to test the effects of HA It was observed that both humic fractions and the HM extract were able to change the root development, improving the number of lateral roots and their development in comparison to control plants The promotion of root growth by the three organic matter fractions was higher than that observed by 10 26 mol L 21 indole acetic acid The treatment of MT tomato mutant, less sensitive to auxin, with HA did not promote the emergence of lateral roots, being an additional indication of auxin-like activities of HA However, some organic matter fractions exhibited, besides promotion of lateral roots number, increase in the length of principal root, which is not a typical auxin effect, indicating that these substances could contain other physiologically active substances
TL;DR: High levels of aflatoxin and ochratoxin A producers were found at all stages of poultry feed processing and high natural contamination with aflatoxins and Ochrat toxin A was found in the samples.
Abstract: Poultry feeds are prone to fungal growth and mycotoxin production during processing. The identification of biota with the ability to produce mycotoxins is essential. The aims of this study were (1) to monitor the mycobiota counts at different stages of poultry feed processing; (2) to determine the occurrence of Aspergillus species; (3) to evaluate the natural incidence of aflatoxins and ochratoxin A. The ability of Aspergillus spp. and its teleomorphs isolated here to produce these toxins was also investigated. Samples (144) were collected at random from a factory in Brazil. The occurrence of Aspergillus and Eurotium species was demonstrated on DRBC and DG18 media and the production of aflatoxins and ochratoxin A and their natural incidence were determined by TLC and HPLC methods. A. flavus and E. chevalieri were the most prevalent species isolated. Fungal contamination was not found after the pelleting process, though Aspergillus and Eurotium species were recovered from trough samples. High levels of aflatoxin and ochratoxin A producers were found at all stages of poultry feed processing. Also, high natural contamination with aflatoxins and ochratoxin A was found in the samples. Contact of feed with remainder poultry feed could lead to fungal contamination, so the risk of aflatoxin and/or ochratoxin A contamination of feed must be taken into account.
TL;DR: Ant activity can have relevant and possibly lasting effects on seed fate of plants adapted for vertebrate dispersal in the cerrado savanna and whether seed cleaning can influence seed germination is investigated.
Abstract: Ants frequently interact with non-myrmecochorous diaspores on the ground in neotropical savannas. Our objective was to quantify the removal rate of these diaspores by ants and vertebrates in order to test the predator avoidance hypothesis, and to test how diaspore traits influence removal by ants and dispersal distance. We also investigated whether seed cleaning (removal of fruit matter simulating ant activity) can influence seed germination. We performed removal experiments with nine diaspore species in a reserve of cerrado savanna in south-east Brazil. Considerable differences in removal rates were found among the nine species. We found a positive linear relationship between lipid content and removal rates for five diaspore species. Vertebrate predation pressure was low for most species, limiting the benefits that ants can provide to plants to escape predators. Ants displace diaspores up to 25 m, which may increase the chance of a seed hitting a safe site. Smaller diaspores attain longer distances of dispersal than large ones. Seed cleaning increased the germination rate for five out of six species tested in greenhouse experiments. Ant activity can have relevant and possibly lasting effects on seed fate of plants adapted for vertebrate dispersal in the cerrado savanna.
TL;DR: In this article, the authors studied the adsorption behavior of fatty acids (acetic, propionic, and butyric) on activated carbon and on modified and unmodified montmorillonite clays as a function of temperature and initial concentration of the adsorbate.
TL;DR: Perineal urethrostomy was performed in all cases and they were evaluated for 6 months after surgery and the clients considered their cats to have a good quality of life following surgery.
Abstract: Fifteen cats were evaluated with urethral obstruction. Penile trauma by catheterization was the major indication for perineal urethrostomy. Ten cats had developed a urethral stricture and five had rupture of the urethra following medical management. All cats had abnormalities in penis and/or prepuce and/or scrotal sacs including hyperemia or swelling. Perineal urethrostomy was performed in all cases and they were evaluated for 6 months after surgery. Few complications were noted. Urinary tract infection was the most frequent complication observed. The clients considered their cats to have a good quality of life following surgery.
TL;DR: In this paper, the use of dehydrated eggplant flour in the composition of crackers in order to present a high level of fiber while keeping their sensorial quality was investigated.
Abstract: Due to the fact that eggplant (Solanum melongena, L.) presents a high concentration of dietary fiber, and also that crackers show a great potential to be used as a nutritive product, the aims of this present work are the use of dehydrated eggplant flour in the composition of crackers in order to present a high level of fiber while keeping their sensorial quality. Levels of 10, 15 and 20% of eggplant flour where used. In the crackers, the chemical and physical characteristics were evaluated. In the final product, the concentration of protein, ash, lipids and total dietary fibers increased as the level of eggplant flour increased. On the other hand, the expansion and the weight decreased and the color became more intense. Therefore, crackers, of all three levels of eggplant flour, can be classified as high dietary fiber and ready-to-eat food.
TL;DR: In this paper, the Humic acid fraction (HA) was extracted from the 0-20 cm layer of Amazonian dark earth soils (Terra Preta do Indio) under forest and agricultural use.
Abstract: Amazonian dark earth soils that have anthropogenic A horizon (Au) present high natural fertility usually attributed to their high organic matter content and to their higher reactivity. In this study humic substances were quantified and the humic acids (HA) extracted from the 0-20 cm layer of Amazonian dark earth soils (Terra Preta do Indio) under forest and agricultural use were characterized. Adjacent soils with no Au horizon were also investigated. The HA were characterized through the thermogravimetric analysis, elemental composition analysis and characterization of functional groups (total, carboxylic, and phenolic). The A horizon of the anthropogenic soils presented higher total carbon level compared to adjacent soils. Among the humic fractions, the humin was the most abundant. The humic acid fraction (HA) was the dominant among the alkaline soluble fractions. The humic acids of the anthropogenic soils, both under forest and cultivation, showed higher humification degree compared to the non-anthropogenic soils. The agricultural cultivation affected the humic acids stability and reactivity in the anthropogenic soils.
TL;DR: A review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities is given in this article.
Abstract: This paper is a review of the history, synthesis and application of organophosphorus compounds, especially of those of pentavalent phosphorus, such as phosphoramidates, phosphorothioates, phosphonates and phosphonic acids with insecticide and anticancer activities The organophosphorus compounds with agrochemical applications show great structural variety, They include not only insecticides, but also fungicides, herbicides, and others The large variety of commercially available organophosphorus pesticides is remarkable Even more interesting is the high efficiency of some organophosphorus compounds as anticancer agents such as cyclophosphamide and its derivatives
TL;DR: Differences were observed between intoxicated rabbits and controls with respect to absolute and relative liver and kidney weight, hepatic function, serum urea and creatinine levels and Sa/So ratio.
TL;DR: This is the first report of feline cytauzoonosis in P. leo and of a confirmed infection by Cytauxzoon felis in felidae in South America.
TL;DR: It seems that stabilizing the population by a judicious control program facilitated the distribution of the pathogens throughout the colony, while the general well-being of the cats was not seriously affected.
TL;DR: In this paper, a biotic integrity index was applied to assess the ecological health at seven sites of a ca. 338 km extension of the Paraiba do Sul river, in bracketing a large urban industrial complex.
Abstract: A index of biotic integrity (IBI) was applied to assess the ecological health at seven sites of ca. 338 km extension of the Paraiba do Sul river, in bracketing a large urban-industrial complex. The aim was to evaluate the index response to changes in environmental quality during two seasons (winter/dry versus. summer/wet). Eight metrics were selected to IBI in three categories: 1) species richness and habitat composition; 2) indicator species; and 3) trophic structure. The IBI, based on the least impacted regional condition, showed the highest value at the most upstream site (Queluz=km 0) - Acceptable, then decreasing downstream and reaching the lowest record at Volta Redonda (km 125) - Impacted; afterwards there was an increasing quality toward the most downstream sites until reaching better scores at Alem Paraiba (km 338) - Moderate Impacted/ Acceptable. During the winter/dry seasons a clearer spatial trend was detected when compared with oscillations in summer/wet. The IBI proved to be a suitable tool to evaluate environmental quality in this tropical and very altered large river, since it was sensitive to non-source point pollution changes, which occurred all over the studied area.
TL;DR: The hypothesis that the agent causing canine hepatozoonosis in the areas studied in Brazil is H. canis is confirmed, supporting previous reports that were based on morphological and morphometric analyses.
TL;DR: The cytotoxic activity of amino (3a-d), aza-1-antraquinone (4a-e) lapachol derivatives against Ehrlich carcinoma and human K562 leukemia cells was investigated and showed dose-dependent growth-inhibiting activities and that the amino derivatives were active against the assayed cells, whereas the 4a- e derivatives were not.
Abstract: The cytotoxic activity of amino (3a-e), aza-1-antraquinone (4a-e) lapachol derivatives against Ehrlich carcinoma and human K562 leukemia cells was investigated. Cell viability was determined using MTT assay, after 48 (Ehrlich) or 96 h (K562) of culture, and vincristine (for K562 leukemia) and quercetin (for Ehrlich carcinoma) were used as positive controls. The results showed dose-dependent growthinhibiting activities and that the amino derivatives were active against the assayed cells, whereas the 4a-e derivatives were not. The allylamine derivative 3a was the most active against Ehrlich carcinoma, with IC50 = 16.94 ± 1.25 µM, and against K562 leukemia, with IC50 = 14.11 ± 1.39 µM. The analogous lawsone derivative, 5a, was also active against Ehrlich carcinoma (IC50 = 23.89 ± 2.3 µM), although the 5d and 5e derivatives showed lower activity. The interaction between 3a-d and calf thymus DNA was investigated by fluorimetric titration and the results showed a hyperchromic effect indicating binding to DNA as presented of ethidium bromide, used as positive control. The inhibitory action on DNA-topoisomerase II-α was also evaluated by a relaxation assay of supercoiled DNA plasmid, and the etoposide (200 µM) was used as positive control. Significant inhibitory activities were observed for 3a-d at 200 µM and a partial inhibitory action was observed for lapachol and methoxylapachol.
TL;DR: In this paper, the authors analyzed the factors structuring demersal fish community in a tropical bay in southeastern Brazil and found that the largest part of the explained variation occurred as a result of the spatial structure of environmental variables, which means that both species and environmental variables presented similar spatial structure.
Abstract: This study analyzed the factors structuring demersal fish community in a tropical bay in southeastern Brazil. The results were used to quantify the partitioning of ecological variation among the environmental, spatial and temporal components molding the fish community. Three bay zones (inner, middle and outer) were defined according to depth and salinity gradient. Monthly samplings were conducted by bottom trawl tows during daylight hours, between October 1998 and September 1999. In each zone, three replicate samples were taken. Ninety-three fish species from 73 genera and 37 families were recorded in the 108 samples. Two demersal fish assemblages were evidenced, one in the inner and the other in the outer zone. These assemblages were characterized by changes in species composition and relative abundance. Depth, followed by transparency and salinity, influenced spatial pattern of fish assemblages. The largest part of the explained variation occurred as a result of the spatial structure of environmental variables, which means that both species and environmental variables presented similar spatial structure. The spatial effect, not the seasonal, explained the highest part of species variations. The amount of unexplained variation was relatively high (76%), even assuming that part of it is due to nondeterministic fluctuation, which could be due to local effects of unmeasured (biotic and abiotic) controlling variables. Knowing the relative importance of these factors can be of decisive importance when applying casual hypotheses in the framework of some precise ecological theory and should facilitate management, planning, and usage of bay resources.
TL;DR: Density of ant species and abundance varied significantly between habitats and seasons; ant diversity varied only between habitats; Homogeneous habitat had lower ant species density, abundance and diversity than heterogeneous habitats.
Abstract: The effects of environmental factors on the richness, diversity and abundance of ants were studied in the Restinga da Marambaia, south coast of Rio de Janeiro State, Brazil. The samples were taken using pitfall traps in August/2004 (winter) and March/2005 (summer) in three different vegetation types: (1) herbaceous ridge palmoid (homogeneous habitat); (2) shrub dune thicket and (3) ridge forest (heterogeneous habitats). At each habitat a range of environmental attributes was recorded: soil temperature and humidity, percentage of soil covering by litter and litter depth. Ninety-two ant species belonging to 36 genera and eight subfamilies were recorded. Density of ant species and abundance varied significantly between habitats and seasons; ant diversity varied only between habitats. Homogeneous habitat had lower ant species density, abundance and diversity than heterogeneous habitats. The two first variables were positively correlated with litter depth and both were higher in summer than in winter samples. There were more species of Ponerinae and Ectatomminae in heterogeneous than in the homogeneous habitat, whereas the Formicinae species were more abundant in the later.
TL;DR: The eutrophic environment of Funil reservoir did not seem to influence morphologic patterns of the structures (oesophagus, stomach and intestine) and no modification was observed in the mucous cells activity.
Abstract: Histological structures of the digestive traits of Pimelodus maculatus La Cepede, 1803, in the Funil reservoir (22o30'- 22o35'S; 44o35'- 44o40'W) were described using haematoxilin-eosin (HE), trichome Gomori, periodic acid Schiff (PAS) and alcian blue (AB) pH 2.5 techniques. The main aim of this study was to detect the levels of glycoproteins (GPs) in the mucous tunic based in histochemical techniques and to characterize eventual alteration in the digestive tract of this species in a polluted system. Fifty-four adult individuals collected between April-2003 and July-2004 (TL=19-38 cm) were examined. The mucosa showed longitudinal folds in the buccopharyngeal cavity, with a stratified squamous epithelium. The oesophagus showed epithelium similar to buccopharyngeal cavity, with a predominance of mucous cells, which reacted strongly with the used methods. The stomach showed three regions: cardic, fundic and pyloric. The mucous tunic is continuously revested by a single cylindrical epithelium which showed positive reaction to AB and PAS only at the apical cells surface. The proper tunic has tubular glands that ramify gradatively, being a cellular type named oxyntopeptic, related to chloridric acid and pepsinogenic cells synthesis. The intestine showed vilosities, with the mucous tunic revested by a single cylindrical epithelium with striated planure and caliciform cells. The duodenum submucosa layer was located at the coledocum opening, as a single cylindrical epithelium lacking caliciforms cells, reacting positively with both PAS and AB. The eutrophic environment of Funil reservoir did not seem to influence morphologic patterns of the structures (oesophagus, stomach and intestine) and no modification was observed in the mucous cells activity.
TL;DR: The parasite communities of the studied fishes showed scarcity of significant correlations of parasitic abundance, species richness and diversity with the size of the host, and could be originated by the oligotrophic characteristics of the Lajes Reservoir.
Abstract: Entre abril de 2002 e julho de 2003, foram necropsiados 231 especimes de peixes: 39 Astyanax bimaculatus (Linnaeus, 1758), 79 A. fasciatus (Cuvier, 1819), 23 Hypostomus affinis (Steindachner, 1877), 26 Hoplias malabaricus (Bloch, 1794), 30 Loricariichthys castaneus (Castelnau, 1855) e 34 Trachelyopterus striatulus (Steindachner, 1876) provenientes do Reservatorio de Lajes (22o42' - 22o50'S, 43o53' 44o05'O), Estado do Rio de Janeiro, Brasil, para estudo das suas comunidades parasitarias. A maioria dos especimes de H. affinis (95,6%) e H. malabaricus (84,6%) estavam parasitados por pelo menos uma especie de metazoario. Em A. bimaculatus, A. fasciatus, L. castaneus e T. striatulus 41%, 39,2%, 56,7% e 14,7% dos especimes estavam parasitados, respectivamente. Foram coletadas oito diferentes especies de metazoarios parasitos: 2 em A. bimaculatus, 3 em A. fasciatus, 3 em H. affinis, 4 em H. malabaricus, 4 em L. castaneus e 1 em T. striatulus. As comunidades de metazoarios parasitos das seis especies de peixes estudadas apresentaram tipico padrao de distribuicao agregada. Foram observados dois casos de correlacao negativa entre a abundância e a prevalencia parasitarias e o comprimento total dos hospedeiros. A comunidade parasitaria de L. castaneus apresentou os maiores valores de intensidade media, indice de dispersao e diversidade. As comunidades parasitarias dos peixes estudados apresentaram escassez de correlacao entre a abundância, riqueza parasitaria e diversidade com o comprimento total dos hospedeiros. Os baixos valores de riqueza e diversidade das comuni-dades parasitarias podem ser atribuidos as caracteristicas oligotroficas do Reservatorio de Lajes.
Abstract: The aim of this study was to evaluate the stocks, and quality of the soil organic matter (SOM) through the use of solid state 13C nuclear magnetic resonance (13C NMR), electronic paramagnetic resonance (EPR) and fluorescence spectroscopy of a fine clay fluventic Eutrichrept after long-term sugarcane cultivation. In one area, sugarcane has been grown for 55 years no field burning before harvest. In another area managed under the traditional system the crop field has been burned before harvest for 35 years; vinasse has been applied on one part (at a rate of 120 m3 ha-1 yr -1), but not on another. The increases of 157 and 57 % in C stocks of humic acids in the area cultivated without field burning for 55 years were related with the increase in the aromaticity degree as well as lower acidity of the SOM, as shown by 13C NMR spectroscopy. The semiquinone-type free radical concentration, as observed by EPR, and intensity of fluorescence emission were higher in the humic acid extracted from soils under management system without field burning before harvest. Significant changes in the humification process were observed in the areas with crop trash preservation. However, in areas where sugar-cane fields were burnt at harvest, vinasse application for 35 years resulted in only minor changes in the organic matter quality and C stocks. These data indicate a rapid evolution of the soluble organic matter added to the soil through vinasse application.
TL;DR: Forest and restinga are continuous in Marambaia and represent the richest habitats for lizards, comprising nine and eight species, respectively, and the possibility of genetic variability loss due to the geographical isolation of the area and the apparent difficulty of re-colonization in the case of local loss of diversity are worrying issues for the conservation of MarambaIA herpetofauna.
Abstract: Carvalho, A.L.G., Araujo, A.F.B. and Silva, H.R. Lizards of Marambaia, an insular remnant of Restinga and Atlantic Forest in the State of Rio de Janeiro, Brazil. Biota Neotrop. May/Aug 2007 vol. 7, no. 2. http:// www.biotaneotropica.org.br/v7n2/pt/abstract?inventory+bn03407022007. ISSN 1676-0603. This work presents the results of a survey of the lizard species that occur in Marambaia, RJ. Twelve species of lizards, distributed in seven families were registered. Teiidae is the richest family (3 spp.), followed by Gekkonidae (2), Scincidae (2), Tropiduridae (2), Gymnophthalmidae (1), Leiosauridae (1), and Polychrotidae (1). The lizard fauna of Marambaia is similar to that occurring in other localities in the southeastern coast of Brazil. Nevertheless, Marambaia harbors Cnemidophorus littoralis and Liolaemus lutzae, species restricted to restinga habitats in Rio de Janeiro State and considered under threat. The area also protects typical forest species, including the arboreal lizards Enyalius brasiliensis and Anolis cf. fuscoauratus. Forest and restinga are continuous in Marambaia and represent the richest habitats for lizards, comprising nine and eight species, respectively. The possibility of genetic variability loss due to the geographical isolation of the area, and the apparent difficulty of re-colonization in the case of local loss of diversity, added to environmental modifications caused by human activities, are worrying issues for the conservation of Marambaia herpetofauna.