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941.
A cave bat community from a semiarid region in eastern Brazil was studied during the dry season. A high diversity was observed, with thirteen species recorded. Except for Micronycteris minuta and Lionycteris spurrelli, these bats were also found in other Brazilian karstic areas. The commonest species were the hematophague Desmodus rotundus, the omnivore Carollia perspicillata, and the insectivore Natalus stramineus. The bats formed itinerant colonies, moving frequently inside the cave. L. spurrelli was previously known from Amazonia, usually associated with evergreen forests. The present record extends its range 1600 km to the south. A disjunct distribution explains some morphological differentiation between Amazonia and Olhos d'Água cave populations. The latter may be a relict of former continuous forest vegetation, which has been fragmented after the climatic optimum. Dispersion through the Cerrado forest gallery is also possible. 相似文献
942.
943.
Cinara L. Gonçalves Gislaine T. Rezin Gabriela K. Ferreira Isabela C. Jeremias Mariane R. Cardoso Samira S. Valvassori Bruna J. P. Munhoz Gabriela D. Borges Bruno N. Bristot Daniela D. Leffa Vanessa M. Andrade João Quevedo Emilio L. Streck 《Molecular and cellular biochemistry》2013,380(1-2):171-176
Obesity is a chronic and multifactorial disease, whose prevalence is increasing in many countries. Pharmaceutical strategies for the treatment of obesity include drugs that regulate food intake, thermogenesis, fat absorption, and fat metabolism. Fenproporex is the second most commonly consumed amphetamine-based anorectic worldwide; this drug is rapidly converted in vivo into amphetamine, which is associated with neurotoxicity. In this context, the present study evaluated DNA damage parameters in the peripheral blood of young and adult rats submitted to an acute administration and chronic administration of fenproporex. In the acute administration, both young and adult rats received a single injection of fenproporex (6.25, 12.5 or 25 mg/kg i.p.) or vehicle. In the chronic administration, both young and adult rats received one daily injection of fenproporex (6.25, 12.5, or 25 mg/kg i.p.) or Tween for 14 days. 2 h after the last injection, the rats were killed by decapitation and their peripheral blood removed for evaluation of DNA damage parameters by alkaline comet assay. Our study showed that acute administration of fenproporex in young and adult rats presented higher levels of damage index and frequency in the DNA. However, chronic administration of fenproporex in young and adult rats did not alter the levels of DNA damage in both parameters of comet assay. The present findings showed that acute administration of fenproporex promoted damage in DNA, in both young and adult rats. Our results are consistent with other reports which showed that other amphetamine-derived drugs also caused DNA damage. We suggest that the activation of an efficient DNA repair mechanism may occur after chronic exposition to fenproporex. Our results are consistent with other reports that showed some amphetamine-derived drugs also caused DNA damage. 相似文献
944.
Cibelle Mariano Inês Palmela Pedro Pereira Adelaide Fernandes Ana Sofia Falcão Filipa Lourenço Cardoso Ana Rita Vaz Alexandre Rainha Campos António Gonçalves-Ferreira Kwang Sik Kim Dora Brites Maria Alexandra Brito 《Cell and tissue research》2013,351(3):397-407
Tricellulin is a tight junction (TJ) protein, which is not only concentrated at tricellular contacts but also present at bicellular contacts between epithelial tissues. We scrutinized the brain for tricellulin expression in endothelial and neural cells by using real-time polymerase chain reaction, Western blot and immunohistochemical and immunocytochemical analysis of cultured brain cells and paraffin sections of brain. Tricellulin mRNA was detected in primary cultures and in a cell line of human brain microvascular endothelial cells. Protein expression was confirmed by Western blot and immunofluorescence analysis, which further highlighted the localization of tricellulin in the cell membrane at tricellular and along bicellular contacts, and in the nucleus and perinuclear region. Compared with the well-studied TJ protein, zonula occludens-1, tricellulin expression was less marked at the cell membrane but more evident in the nuclear and perinuclear regions. The presence of tricellulin in cultured endothelial cells was corroborated by immunohistochemical and immunofluorescence staining in brain blood vessels, where it was colocalized with another TJ protein, claudin-5. Tricellulin mRNA was detected in neurons and astrocytes, whereas protein expression was observed in astrocytes but not in neurons, as shown by immunofluorescence analysis. This study reveals the presence and subcellular distribution of tricellulin in brain endothelial cells, both in vitro and in situ and its colocalization with other relevant TJ proteins. Moreover, it demonstrates the expression of the protein in astrocytes opening new avenues for future research to establish the biological significance of tricellulin expression in glial cells. 相似文献
945.
Tatiana Tavares Carrijo Mário Luís Garbin Wellerson Picanço Leite Cláudia Barbieri Ferreira Mendonça Roberto Lourenço Esteves Vania Gonçalves-Esteves 《Plant Systematics and Evolution》2013,299(7):1275-1283
Pollen morphology is an important source of information to increase systematic resolution in Asteraceae, especially in Vernonieae. Aiming to investigate if palynological traits give support to Caatinganthus, Strophopappus and Xiphochaeta as separate genera from Stilpnopappus, we used cluster analysis followed by a test of group sharpness. Further, ordination analysis was applied to detect informative pollen traits associated with the revealed groups. The analyses evidenced five groups: (G1) Caatinganthus rubropappus as a single-species group; (G2) species of Stilpnopappus; (G3) Xiphochaeta aquatica as a single-species group; (G4) Strophopappus bicolor, S. glomeratus, S. villosus, S. ferrugineus, S. pohlii and S. speciosus; (G5) Strophopappus bullatus and S. regnelli. The interruption in the middle of the muri in apertural lacunae explains the single-species group Caatinganthus rubropappus. The thickness of sexine, the type of apertures (porate or colporate), and spine dimensions (length, thickness and distance from each other) are the traits explaining differences between species of Stilpnopappus and Strophopappus. Equatorial lacunae give support to Xiphochaeta aquatica as a single-species group, despite the smaller size of pollen grains of this species as compared to the others species analyzed. The differences among pollen morphology give support to Caatinganthus, Stilpnopappus, Strophopappus and Xiphochaeta as genera according to the taxonomic classification currently accepted. The used approach was efficient to reveal individual pollen traits informative to explain the sharp groups, and was an effective alternative to the use of “pollen types”. 相似文献
946.
Aline Silva Braga Letícia Dragonetti Girotti Leticia Lobo de Melo Simas Juliana Gonçalves Pires Vinícius Taioqui Pelá Marília Afonso Rabelo Buzalaf 《Biofouling》2013,29(7):796-804
AbstractThis work evaluated the effects of commercial toothpastes and mouth rinses containing natural/herbal agents on biofilm viability, extracellular polysaccharide (EPS) production and on enamel demineralization in vitro. Microcosm biofilm was produced on bovine enamel for 5?days and treated daily with: Orgânico natural® (toothpaste/mouth rinse), Boni Natural Menta &; Malaleuca® (toothpaste/mouth rinse), Propolis &; Myrrh® (toothpaste), Colgate Total 12 Clean Mint® (toothpaste, positive control), Malvatricin® Plus (mouth rinse), PerioGard® (mouth rinse, positive control) or PBS (negative control). Tom’s Propolis &; Myrrh® and Colgate Total 12® toothpastes and Malvatricin® Plus and PerioGard® mouth rinses significantly reduced biofilm viability (p?0.05). Only PerioGard® had significant effects on biofilm thickness and EPS. Despite the indication that Tom’s Propolis &; Myrrh® significantly reduced lesion depth, only Colgate Total 12® significantly reduced mineral loss. Malvatricin® Plus significantly reduced mineral loss and lesion depth, as did PerioGard®. Some herbal products, Malvatricin® Plus and Tom’s Propolis &; Myrrh®, showed anticaries effects. 相似文献
947.
Johnson T Gaunt TR Newhouse SJ Padmanabhan S Tomaszewski M Kumari M Morris RW Tzoulaki I O'Brien ET Poulter NR Sever P Shields DC Thom S Wannamethee SG Whincup PH Brown MJ Connell JM Dobson RJ Howard PJ Mein CA Onipinla A Shaw-Hawkins S Zhang Y Davey Smith G Day IN Lawlor DA Goodall AH;Cardiogenics Consortium Fowkes FG Abecasis GR Elliott P Gateva V;Global BPgen Consortium Braund PS Burton PR Nelson CP Tobin MD van der Harst P Glorioso N Neuvrith H Salvi E Staessen JA Stucchi A Devos N 《American journal of human genetics》2011,(6):688-700
948.
Residual dipolar couplings (RDCs) were used as restraints in fully solvated molecular dynamics simulations of reduced substrate- and carbonmonoxy-bound cytochrome P450(cam) (CYP101A1), a 414-residue soluble monomeric heme-containing camphor monooxygenase from the soil bacterium Pseudomonas putida. The (1)D(NH) residual dipolar couplings used as restraints were measured in two independent alignment media. A soft annealing protocol was used to heat the starting structures while incorporating the RDC restraints. After production dynamics, structures with the lowest total violation energies for RDC restraints were extracted to identify ensembles of conformers accessible to the enzyme in solution. The simulations result in substrate orientations different from that seen in crystallographic structures and a more open and accessible enzyme active site and largely support previously reported differences between the open and closed states of CYP101A1. 相似文献
949.
Almeida Júnior Edivan S. Martínez Aingeru Gonçalves Ana Lúcia Canhoto Cristina 《Hydrobiologia》2020,847(16):3427-3435
Hydrobiologia - Freshwater salinization is a matter of major global concern due to its consequences on the aquatic biota and ecosystems functioning. Salt contamination negatively affects the leaf... 相似文献
950.