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991.
Ana Paula Dini Andreote Marcelo Gomes Marçal Vieira Vaz Diego Bonaldo Genuário Laurent Barbiero Ary Tavares Rezende‐Filho Marli Fátima Fiore 《Journal of phycology》2014,50(4):675-684
Saline‐alkaline lakes are extreme environments that limit the establishment and development of life. The Nhecolândia, a subregion of the Pantanal wetland in Brazil, is characterized by the existence of ~500 saline‐alkaline lakes, which support an underexplored and rich diversity of microorganisms. In this study, unicellular and homocytous cyanobacteria from five saline‐alkaline lakes were accessed by culture‐dependent approaches. Morphological evaluation and analyses of near complete sequences (~1400 nt) of the 16S rRNA genes were applied for phylogenetic and taxonomic placement. This polyphasic approach allowed for the determination of the taxonomic position of the isolated strains into the following genera: Cyanobacterium, Geminocystis, Phormidium, Leptolyngbya, Limnothrix, and Nodosilinea. In addition, fourteen Pseudanabaenales and Oscillatoriales representatives of putative novel taxa were found. These sequences fell into five new clades that could correspond to new generic units of the Pseudanabaenaceae and Phormidiaceae families. 相似文献
992.
Rafael Magalhães Rabelo Felipe Ennes Silva Tatiana Vieira Jefferson Ferreira-Ferreira Fernanda Pozzan Paim Wallace Dutra José de Souza e Silva Júnior João Valsecchi 《Primates; journal of primatology》2014,55(2):167-171
The black-faced black spider monkey (Ateles chamek) is endangered because of hunting and habitat loss. There are many gaps in our understanding of its geographic distribution. The Ucayali–Solimões–Amazon fluvial complex is currently recognized as the northern boundary of the species’ range, although published reports have indicated that it occurs north of the Rio Solimões. In this study we investigate published records, generate new field records, and assess the current information concerning the northern boundary of this species’ range. We conducted the study at the Mamirauá Sustainable Development Reserve in the central Brazilian Amazon, an area of 1,124,000 ha that consists entirely of Amazonian flooded forest (várzea). We collected data on the occurrence of the species from museum specimens and through field surveys, including interviews with local residents, direct observations, and the collection of new museum specimens. We confirmed the presence of A. chamek at 17 locations in the reserve, one of which was an island formed by a river bend cut-off that would have effectively taken any resident spider to the (new) north bank of the Solimões. We therefore conclude that fluvial dynamics were involved in creating the conditions for the dispersal and colonization of the species on the northern bank of the Rio Solimões. The data we present extends the known distribution of the species and increases its representation in protected areas. 相似文献
993.
Nuno M Guimar?es Nuno F Azevedo Maria J Vieira Ceu Figueiredo 《Memórias do Instituto Oswaldo Cruz》2014,109(4):414-419
While the influence of water in Helicobacter pylori culturability
and membrane integrity has been extensively studied, there are little data concerning
the effect of this environment on virulence properties. Therefore, we studied the
culturability of water-exposed H. pylori and determined whether
there was any relation with the bacterium’s ability to adhere, produce functional
components of pathogenicity and induce inflammation and alterations in apoptosis in
an experimental model of human gastric epithelial cells. H. pylori
partially retained the ability to adhere to epithelial cells even after
complete loss of culturability. However, the microorganism is no longer effective in
eliciting in vitro host cell inflammation and apoptosis, possibly due to the
non-functionality of the cag type IV secretion system. These H.
pylori-induced host cell responses, which are lost along with
culturability, are known to increase epithelial cell turnover and, consequently,
could have a deleterious effect on the initial H. pylori
colonisation process. The fact that adhesion is maintained by H.
pylori to the detriment of other factors involved in later infection
stages appears to point to a modulation of the physiology of the pathogen after water
exposure and might provide the microorganism with the necessary means to, at least
transiently, colonise the human stomach. 相似文献
994.
Danuta Sastre Nathália Nogueira da Costa André Luiz Alves de Sá Stefanne Dhúllia Braga Conceição Marcos Roberto Chiaratti Paulo Roberto Adona Samuel Guemra Flávio Vieira Meirelles Simone do Socorro Damasceno Santos Leonardo Sena Otávio Mitio Ohashi Eduardo José Melo dos Santos Moysés dos Santos Miranda 《Theriogenology》2014
995.
Samira D. T. De Prá Gabriela K. Ferreira Milena Carvalho-Silva Júlia S. Vieira Giselli Scaini Daniela D. Leffa Gabriela E. Fagundes Bruno N. Bristot Gabriela D. Borges Gustavo C. Ferreira Patrícia F. Schuck Vanessa M. Andrade Emilio L. Streck 《Neurochemical research》2014,39(1):202-207
Mutations in the tyrosine aminotransferase gene have been identified to cause tyrosinemia type II which is inherited in an autosomal recessive manner. Studies have demonstrated that an excessive production of ROS can lead to reactions with macromolecules, such as DNA, lipids, and proteins. Considering that the l-tyrosine may promote oxidative stress, the main objective of this study was to investigate the in vivo effects of l-tyrosine on DNA damage determined by the alkaline comet assay, in brain and blood of rats. In our acute protocol, Wistar rats (30 days old) were killed 1 h after a single intraperitoneal l-tyrosine injection (500 mg/kg) or saline. For chronic administration, the animals received two subcutaneous injections of l-tyrosine (500 mg/kg, 12-h intervals) or saline administered for 24 days starting at postnatal day (PD) 7 (last injection at PD 31), 12 h after the last injection, the animals were killed by decapitation. We observed that acute administration of l-tyrosine increased DNA damage frequency and damage index in cerebral cortex and blood when compared to control group. Moreover, we observed that chronic administration of l-tyrosine increased DNA damage frequency and damage index in hippocampus, striatum, cerebral cortex and blood when compared to control group. In conclusion, the present work demonstrated that DNA damage can be encountered in brain from animal models of hypertyrosinemia, DNA alterations may represent a further means to explain neurological dysfunction in this inherited metabolic disorder and to reinforce the role of oxidative stress in the pathophysiology of tyrosinemia type II. 相似文献
996.
Jessié M. Gutierres Fabiano B. Carvalho Maria Rosa C. Schetinger Marília V. Rodrigues Juliano M. Vieira Paula Maldonado Maria do Carmo S. Araújo Roberta Schmatz Naiara Stefanello Jeandre A. S. Jaques Marcio Costa Vera Morsch Cinthia M. Mazzanti Victor Pimentel Sonia Terezinha A. Lopes Roselia M. Spanevello 《Journal of physiology and biochemistry》2014,70(2):487-496
The aim of this study was to assess whether α-tocopherol administration prevented alterations in the ectonucleotidase activities and platelet aggregation induced by high-fat diet in rats. Thus, we examined four groups of male rats which received standard diet, high-fat diet (HFD), α-tocopherol (α-Toc), and high-fat diet plus α-tocopherol. HFD was administered ad libitum and α-Toc by gavage using a dose of 50 mg/kg. After 3 months of treatment, animals were submitted to euthanasia, and blood samples were collected for biochemical assays. Results demonstrate that NTPDase, ectonucleotide pyrophosphatase/phosphodiesterase, and 5′-nucleotidase activities were significantly decreased in platelets of HFD group, while that adenosine deaminase (ADA) activity was significantly increased in this group in comparison to the other groups (P?<?0.05). When rats that received HFD were treated with α-Toc, the activities of these enzymes were similar to the control, but ADA activity was significantly increased in relation to the control and α-Toc group (P?<?0.05). HFD group showed an increased in platelet aggregation in comparison to the other groups, and treatment with α-Toc significantly reduced platelet aggregation in this group. These findings demonstrated that HFD alters platelet aggregation and purinergic signaling in the platelets and that treatment with α-Toc was capable of modulating the adenine nucleotide hydrolysis in this experimental condition. 相似文献
997.
V. M. Lemos A. S. Varela Jr. P. R. Schwingel J. H. Muelbert J. P. Vieira 《Journal of fish biology》2014,85(3):671-687
The mullet Mugil liza occurs along the Atlantic coast of South America from Venezuela to Argentina, but 95% of the commercial catch is collected from south Brazil between São Paulo and Argentina. Mugil liza is a single spawner with oocyte development occurring synchronously in two groups. Spawning happens in marine areas and occurs after migration. The reproductive migration occurs from Argentina (38° S) to the southern Brazilian states (24–26° S) from April to July, with peak spawning in June between northern Santa Catarina and Paraná. The presence of hyaline oocytes was associated with high salinity and sea surface temperatures of 19–21° C, and followed the seasonal northward displacement of these oceanographic conditions. The average size at first maturity (Lm) for both sexes was 408·3 mm total length, LT. Males (Lm = 400·1) matured earlier than females (Lm = 421·9 mm). Fecundity ranged from 818 992 to 2 869 767 oocytes (mean = 1 624 551) in fish that were between 426 and 660 mm LT. 相似文献
998.
Suelem D. Ramalho Lorena R. F. De Sousa Liliane Nebo Stella H. Maganhi Ignez Caracelli Julio Zukerman‐Schpector Maria Inês S. Lima Marcio F. M. Alves M. Fátima das G. F. Da Silva João B. Fernandes Paulo C. Vieira 《化学与生物多样性》2014,11(9):1354-1363
Cathepsins L (catL) and B play an important role in tumor progression and have been considered promising therapeutic targets in the development of novel anticancer agents. Using a bioactivity‐guided fractionation, a series of triterpenoids was identified as a new class of competitive inhibitors towards cathepsin L with affinity values in micromolar range. Among the 14 compounds evaluated, the most promising were 3‐epiursolic acid ( 3 ), 3‐(hydroxyimino)oleanolic acid ( 9 ), and 3‐(hydroxyimino)masticadienoic acid ( 13 ) with IC50 values of 6.5, 2.4, and 2.6 μM on catL, respectively. Most of the evaluated triterpenoids do not inhibit cathepsin B. Thus, the evaluated compounds exhibit a great potential to help in the design of new inhibitors with enhanced potency and affinity towards catL. Docking studies were performed in order to gain insight on the binding mode and SAR of these compounds. 相似文献
999.
1000.
Schetinger MR Vieira VL Morsch VM Balz D 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2001,128(4):731-741
Ecto-enzymes capable of hydrolyzing ATP and ADP (NTPDase) are present in the central nervous system of various species. In the present investigation we studied the synaptosomal NTPDase (ATP diphosphohydrolase, apyrase, E.C. 3.6.1.5) from fish, chicken and rats under different conditions and in the presence of several classical inhibitors. The cation concentration required for maximal activity was 0.5 mM for fish, 1.0 mM for chickens and 1.5 mM for rats with both substrates. The results showed that the pH optimum for all animal preparations was close to 8.0. The temperature used was 25–27°C for fish and 35–37°C for chicken and rat preparations. The inhibitors azide and fluoride only inhibited the preparation at high concentrations (10 mM). Lanthanum (0.1–0.4 mM), N-ethylmaleimide (0.4–3.0 mM) and ouabain (0.5–3.0 mM) had no effect on NTPDase activity from fish, chickens or rats. Orthovanadate (0.1–0.3 mM) only inhibited fish synaptosomal NTPDase. Trifluoperazine (0.05–0.2 mM) and suramin (0.03–0.3 mM) inhibited NTPDase at all concentrations tested. Suramin was the most potent compound in causing inhibition, presenting inhibition at 30 μM. Our results demonstrate that the synaptosomal NTPDase response to several factors is similar in fish, chickens and rats, and that the enzyme presents functional homology. 相似文献