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1.
João Paulo Rodrigues Martins Luiz Carlos de Almeida Rodrigues Lorenzo Toscano Conde Andreia Barcelos Passos Lima Gontijo Antelmo Ralph Falqueto 《Plant biosystems》2020,154(1):87-99
AbstractUnder in vitro culture conditions, plants may present physiological and anatomical disorders, which can interfere negatively after ex vitro transfer. The aim of this investigation was to analyze the impacts of natural ventilation and sucrose supply on the anatomy and physiology of Vriesea imperialis. Plants previously grown in vitro were transferred to culture medium containing 0, 15, 30 or 45?g L?1 sucrose. Three different culture container sealing systems were tested: lids with a green filter (81.35 gas exchanges per day), yellow filter (13.09 gas exchanges per day) or lids with a yellow filter covered with three layers of transparent polyvinylchloride (PVC) film (blocking fluent gas exchange). Sucrose concentrations influenced thickness, lignin and suberin deposition of exodermis cell wall. The modifications verified in leaves, such as higher density of stomata and trichome scales, showed that sucrose can induce osmotic stress in the plants. Photomixotrophic conditions, using containers with intermediate rate of gas exchange (yellow filter) and with 15–30?g L?1 sucrose, produced an improvement in the growth traits and did not induce anatomical and physiological disturbances. 相似文献
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Paulo Roberto Melo-Sampaio Paulo Passos Antoine Fouquet Ana Lucia Da Costa Prudente Omar Torres-Carvajal 《分类学与生物多样性》2019,17(3):207-229
The Guiana Shield harbours one of the best preserved and largest extents of tropical forest on Earth and an immense biodiversity. The herpetofauna of this region remains poorly known. The species-rich snake genus Atractus contains ~140 species, many with complicated taxonomic histories, including A. schach. Examination of specimens in museums and newly collected material from French Guiana has allowed the illustration of hemipenial morphology for the first time and an expanded diagnosis. Concatenated molecular phylogenetic (mitochondrial and nuclear genes) and phenotypic (morphometrics, external and hemipenial morphology) analyses confirm non-monophyly of the A. flammigerus group and indicate that A. schach is a species complex with three new species described here. The geographic distribution of A. schach sensu stricto is restricted to Guiana, Surinam, and French Guiana north of Tumucumaque massif. Populations tentatively assigned to A. schach from the east from French Guiana in the Roura lowlands to Almeirim, and from central Amazonia between the Negro and Trombetas rivers in Brazil are also recognized as new species. Our results suggest that populations from south of the Amazon River are not conspecific with those from the Guiana Shield.
http://www.zoobank.org/urn:lsid:zoobank.org:pub:A7AE40BC-4716-4302-B3BE-1F43600B0A72 相似文献
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Mayume Shibuya Giovana Bergheme Sara Passos Ivonete Queiroz Jamile Rêgo Lucas P. Carvalho Paulo R.L. Machado 《Microbes and infection / Institut Pasteur》2019,21(2):94-98
Understanding host immune pathways associated with tissue damage during reactions are of upmost importance to the development of immune intervention strategies. The participation of monocytes in leprosy reactions was evaluated by determining the frequency of monocyte subsets and the degree of cellular activation through the expression of MHCII and the co-stimulatory molecules CD40, CD80, CD86. Leprosy subjects with or without reactions were included in this cross-sectional study. Peripheral blood mononuclear cell were isolated and stained ex vivo to determine monocyte subsets and the degree of cellular activation by flow cytometry. Intermediate monocytes were increased in leprosy patients with reactions when compared to patients without reactions. Although no difference was detected in the frequency of monocyte subsets between type 1 and 2 reactions, the expression of CD80 was increased in monocytes from patients with type 1 reactions and CD40 was higher in paucibacillary subjects presenting type 1 reactions. Moreover, CD86 and MHC II expression were higher in intermediate monocytes when compared to the other subsets in leprosy reaction types 1 and 2. Intermediate monocyte activation with CD86 and MHCII expression is involved with both type 1 and 2 reactions, whereas CD80 and CD40 expression is related to type 1 reactions. 相似文献
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Gustavo C. Bressan Eduardo C. Moraes Adriana O. Manfiolli Tais M. Kuniyoshi Dario O. Passos Marcelo D. Gomes Jörg Kobarg 《Cellular & molecular biology letters》2009,14(4):657-669
The human SFRS9/SRp30c belongs to the SR family of splicing regulators. Despite evidence that members of this protein family
may be targeted by arginine methylation, this has yet to be experimentally addressed. In this study, we found that SFRS9 is
a target for PRMT1-mediated arginine methylation in vitro, and that it is immunoprecipitated from HEK-293 lysates by antibodies that recognize both mono- and dimethylated arginines.
We further observed that upon treatment with the methylation inhibitor Adox, the fluorescent EGFP-SFRS9 re-localizes to dot-like
structures in the cell nucleus. In subsequent confocal analyses, we found that EGFP-SFRS9 localizes to nucleoli in Adox-treated
cells. Our findings indicate the importance of arginine methylation for the subnuclear localization of SFRS9. 相似文献
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Suzana Passos Chaves Eduardo Caio Torres-Santos Camila Marques Vanessa Ribeiro Figliuolo Pedro Muanis Persechini Robson Coutinho-Silva Bartira Rossi-Bergmann 《Microbes and infection / Institut Pasteur》2009,11(10-11):842-849
The purinergic P2X7 receptor is a membrane protein of leucocytes involved in the clearance of intracellular bacteria such as Chlamydia and Mycobacterium. In this work, we investigated the role and modulation of macrophage P2X7R in intracellular infection with the protozoan parasite Leishmania amazonensis. Upon infection, isolated murine macrophages displayed enhanced expression of P2X7R and were significantly more responsive to extracellular ATP (ATPe)-induced pore opening, as demonstrated by the increased uptake of Lucifer Yellow. This was extended to the in vivo situation, where cells from established cutaneous lesions were more sensitive to ATPe than cells from uninfected mice. ATP treatment of infected macrophages inhibited parasite growth, and this was prevented by pre-treatment with oxidized ATP, a selective antagonist of P2X7R. Parasite killing was unlikely due to induction of nitric oxide production or cytolysis of infected macrophage, as those functions were unaltered with parasite-effective ATPe concentrations. A direct drug effect is also unlike, as ATPe enhanced axenic parasite growth. We found that leishmanial infection rendered wild-type but not P2X7R-deficient macrophages more prone to ATP-induced apoptosis. These results show that macrophage infection with L. amazonensis leads to enhanced expression of functional P2X7R, that upon ligation with ATPe helps in the elimination of the parasites by an as yet unclear mechanism possibly involving host cell apoptosis. 相似文献
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Clarissa Santana Chaves D’Aguiar Petitinga Alzira Kelly Passos Roriz Iara Sordi Joachim-Bravo 《Journal of Applied Entomology》2021,145(6):612-620
Interspecific competition between individuals of different species can result in reductions in their fecundity, growth or survival, reflecting differential exploitation of resources that become intensified due to spatial co-occurrence, ecological similarity and increased population densities. As two species cannot occupy the same niche, coexistence is only possible if the available resources are used in non-overlapping manners such as niche partitioning or the use of refuges. Among agricultural insect pests, such as fruit flies of the family Tephritidae, competitive interactions can result in competitive displacement, host changes, or the expansion or restriction of the numbers of hosts utilized that can have negative consequences for human agricultural activities. We evaluated the competitive interactions between two fruit fly species of the genus Anastrepha, Anastrepha obliqua (Macquart, 1835) and Anastrepha fraterculus (Wiedmann, 1830), on their respective preferred hosts (mangoes and guava). Experiments of larval competition and competition for ovipositioning sites by adult females were performed to compare the parameters of larval development time, numbers of pupae and emerged adults and numbers of ovipositions in the presence or absence of interspecific competition. We observed that the interactions between those species were asymmetrical and hierarchical, and our results suggest a competitive displacement of A. fraterculus by A. obliqua when those two species are present on the same fruit, whether mangoes or guavas. 相似文献