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191.
Priscila Kienteca Lange Denise Rivera Tenenbaum Elisabete de Santis Braga Lúcia S. Campos 《Polar Biology》2007,30(11):1483-1492
Microphytoplankton populations were studied in shallow coastal water (<60 m) near the Brazilian Antarctic Station Comandante
Ferraz (EACF) and three reference areas in Admiralty Bay in early and late summer (2002–2003). Phytoplankton was diverse (113
taxa), but not abundant (103 cells l−1). The highest abundances (>104 cells l−1) were caused by pennate benthic diatoms (Fragilaria striatula Lyngbye) that occurred mainly in early summer, associated with the presence of ice. In late summer, when the water temperature
(−0.4 to 1.5°C), salinity (34 to 35), and phosphate (2.6 to 4.5 μmol l−1) were highest and the dissolved oxygen was lowest (6.4 to 2.9 ml l−1), centric diatoms (Thalassiosira spp.) were more abundant, suggesting an influence of oceanic waters. Phytoplankton abundance (≤102 cells l−1) and chlorophyll a concentrations (0.22 μg l−1) were lowest close to EACF. Pennate diatoms were dominant close to shore and in surface waters elsewhere, probably because
of ice melting or sediment resuspension caused by water mixing. 相似文献
192.
Santos Beatriz da Conceição Daniele Priscila Corrêa Diego Oliveira Passos Matheus Felipe Campos Monique Paiva Adamoski Douglas Galli-Terasawa Lygia Vitória Mariano André Bellin Vargas José Viriato Coelho Kava Vanessa Merlo 《Journal of applied phycology》2022,34(2):729-743
Journal of Applied Phycology - The present study evaluated the effect of blue, red, and white light on the expression of four carotenogenic genes (psy, lyc, bkt, and crtr-r); one gene related to... 相似文献
193.
Iara Oliveira Costa Priscila Barreto de Jesus Tiana da Silva de Jesus Poline dos Santos Souza Paulo Antunes Horta Jos Marcos de Castro Nunes 《Journal of phycology》2019,55(6):1370-1385
The Southwest Atlantic is notable for having extensive reef areas cemented by nongeniculate coralline red algae. Based on an analysis of four genetic markers and morpho‐anatomical features, we clarify the species of Harveylithon in the tropical and warm temperate Southwest Atlantic. Species delimitation methods (mBGD, ABGD, SPN, and PTP), using three markers (psbA, rbcL, and COI), support the recognition of three new species: H. catarinense sp. nov., H. maris‐bahiensis sp. nov., and H. riosmenum sp. nov., previously incorrectly called Hydrolithon samoënse. Our findings highlight the importance of using an approach with several lines of evidence to solve the taxonomic status of the cryptic species. 相似文献
194.
Paula Pierozan Fernanda Ferreira Bárbara Ortiz de Lima Carolina Gonçalves Fernandes Priscila Totarelli Monteforte Natalia de Castro Medaglia Claudia Bincoletto Soraya Soubhi Smaili Regina Pessoa-Pureur 《Experimental cell research》2014
Quinolinic acid (QUIN) is a glutamate agonist which markedly enhances the vulnerability of neural cells to excitotoxicity. QUIN is produced from the amino acid tryptophan through the kynurenine pathway (KP). Dysregulation of this pathway is associated with neurodegenerative conditions. In this study we treated striatal astrocytes in culture with QUIN and assayed the endogenous phosphorylating system associated with glial fibrillary acidic protein (GFAP) and vimentin as well as cytoskeletal remodeling. After 24 h incubation with 100 µM QUIN, cells were exposed to 32P-orthophosphate and/or protein kinase A (PKA), protein kinase dependent of Ca2+/calmodulin II (PKCaMII) or protein kinase C (PKC) inhibitors, H89 (20 μM), KN93 (10 μM) and staurosporin (10 nM), respectively. Results showed that hyperphosphorylation was abrogated by PKA and PKC inhibitors but not by the PKCaMII inhibitor. The specific antagonists to ionotropic NMDA and non-NMDA (50 µM DL-AP5 and CNQX, respectively) glutamate receptors as well as to metabotropic glutamate receptor (mGLUR; 50 µM MCPG), mGLUR1 (100 µM MPEP) and mGLUR5 (10 µM 4C3HPG) prevented the hyperphosphorylation provoked by QUIN. Also, intra and extracellular Ca2+ quelators (1 mM EGTA; 10 µM BAPTA-AM, respectively) prevented QUIN-mediated effect, while Ca2+ influx through voltage-dependent Ca2+ channel type L (L-VDCC) (blocker: 10 µM verapamil) is not implicated in this effect. Morphological analysis showed dramatically altered actin cytoskeleton with concomitant change of morphology to fusiform and/or flattened cells with retracted cytoplasm and disruption of the GFAP meshwork, supporting misregulation of actin cytoskeleton. Both hyperphosphorylation and cytoskeletal remodeling were reversed 24 h after QUIN removal. Astrocytes are highly plastic cells and the vulnerability of astrocyte cytoskeleton may have important implications for understanding the neurotoxicity of QUIN in neurodegenerative disorders. 相似文献
195.
Priscila Andressa Cortez Ana Paula de Souza Caetano Sandra Maria Carmello-Guerreiro Simone Pádua Teixeira 《Flora》2014
Melastomataceae have porate anthers. However, unlike Solanaceae and many monocots, in which the poricidal dehiscence depends on the presence of a mechanical layer (often the endothecium), most members of Melastomataceae have no evident specialized layer related to the poricidal opening. The goal of this study was to characterize the tissues that form the apical pore of the anther in 10 Miconia species, which may help to understand the nearly unknown mechanism of anther dehiscence in this genus, considered to be one of the largest and most diverse New World genera. Before anthesis, the apical pores of all of the species are closed by a uniseriate epidermis, the cells of which lack a cuticle. In contrast, the epidermis of the remainder of the anther is covered by a thick, ornamented cuticle. Among Myrtales, the Melastomataceae form a clade with Alzateaceae, Crypteroniaceae and Penaeaceae, almost all of which have anthers with endothecium lacking wall thickenings. In these families, the endothecium may or may not be present in the mature anther, with degenerating cells in the latter case. Anther dehiscence does not depend on the endothecium as the mechanical layer, and this process is still not well understood. However, in the Miconia species studied here, the cuticle may prevent tissue dehydration, and the pore opening seems to be due to the passive process of dehydration taking place only in the pore region due to the absence of the cuticle. 相似文献
196.
197.
198.
Carolina Soares Moura Pablo Christiano Barboza Lollo Priscila Neder Morato Luciana Hisayama Nisishima Everardo Magalh?es Carneiro Jaime Amaya-Farfan 《PloS one》2014,9(1)
Whey protein hydrolysate (WPH) intake has shown to increase HSP70 expression. The aim of the present study was to investigate whether WPH intake would also influences HSP90, HSP60 and HSP25 expression, as well as associated parameters. Forty-eight male Wistar rats were divided into sedentary (unstressed) and exercised (stressed) groups, and were fed with three different sources of protein: whey protein (WP), whey protein hydrolysate (WPH) and casein (CAS) as a control, based on the AIN93G diet for 3 weeks. WPH intake increased HSP90 expression in both sedentary and exercised animals compared to WP or CAS, however no alteration was found from exercise or diet to HSP60 or HSP25. Co-chaperone Aha1 and p-HSF1 were also increased in the exercised animals fed with WPH in comparison with WP or CAS, consistent with enhanced HSP90 expression. VEGF and p-AKT were increased in the WPH exercised group. No alteration was found in BCKDH, PI3-Kinase (p85), GFAT, OGT or PGC for diet or exercise. The antioxidant system GPx, catalase and SOD showed different responses to diet and exercise. The data indicate that WPH intake enhanced factors related to cell survival, such as HSP90 and VEGF, but does not alter HSP60 or HSP25 in rat skeletal muscle. 相似文献
199.
Rafael D. Loyola Priscila Lemes Frederico V. Faleiro Joaquim Trindade-Filho Ricardo B. Machado 《PloS one》2012,7(9)
A wide range of evidences indicate climate change as one the greatest threats to biodiversity in the 21st century. The impacts of these changes, which may have already resulted in several recent species extinction, are species-specific and produce shifts in species phenology, ecological interactions, and geographical distributions. Here we used cutting-edge methods of species distribution models combining thousands of model projections to generate a complete and comprehensive ensemble of forecasts that shows the likely impacts of climate change in the distribution of all 55 marsupial species that occur in Brazil. Consensus projections forecasted range shifts that culminate with high species richness in the southeast of Brazil, both for the current time and for 2050. Most species had a significant range contraction and lost climate space. Turnover rates were relatively high, but vary across the country. We also mapped sites retaining climatic suitability. They can be found in all Brazilian biomes, especially in the pampas region, in the southern part of the Brazilian Atlantic Forest, in the north of the Cerrado and Caatinga, and in the northwest of the Amazon. Our results provide a general overview on the likely effects of global climate change on the distribution of marsupials in the country as well as in the patterns of species richness and turnover found in regional marsupial assemblages. 相似文献
200.
Priscila C. Albuquerque Radames J.B. Cordero Fernanda L. Fonseca Roberta Peres da Silva Caroline L. Ramos Kildare R. Miranda Arturo Casadevall Rosana Puccia Joshua D. Nosanchuk Leonardo Nimrichter Allan J. Guimaraes Marcio L. Rodrigues 《Fungal genetics and biology : FG & B》2012,49(11):943-954
The cell wall of the yeast form of the dimorphic fungus Paracoccidioides brasiliensis is enriched with α1,3-glucans. In Cryptococcus neoformans, α1,3-glucans interact with glucuronoxylomannan (GXM), a heteropolysaccharide that is essential for fungal virulence. In this study, we investigated the occurrence of P. brasiliensis glycans sharing properties with cryptococcal GXM. Protein database searches in P. brasiliensis revealed the presence of sequences homologous to those coding for enzymes involved in the synthesis of GXM and capsular architecture in C. neoformans. In addition, monoclonal antibodies (mAbs) raised to cryptococcal GXM bound to P. brasiliensis cells. Using protocols that were previously established for extraction and analysis of C. neoformans GXM, we recovered a P. brasiliensis glycan fraction composed of mannose and galactose, in addition to small amounts of glucose, xylose and rhamnose. In comparison with the C. neoformans GXM, the P. brasiliensis glycan fraction components had smaller molecular dimensions. The P. brasiliensis components, nevertheless, reacted with different GXM-binding mAbs. Extracellular vesicle fractions of P. brasiliensis also reacted with a GXM-binding mAb, suggesting that the polysaccharide-like molecule is exported to the extracellular space in secretory vesicles. An acapsular mutant of C. neoformans incorporated molecules from the P. brasiliensis extract onto the cell wall, resulting in the formation of surface networks that resembled the cryptococcal capsule. Coating the C. neoformans acapsular mutant with the P. brasiliensis glycan fraction resulted in protection against phagocytosis by murine macrophages. These results suggest that P. brasiliensis and C. neoformans share metabolic pathways required for the synthesis of similar polysaccharides and that P. brasiliensis yeast cell walls have molecules that mimic certain aspects of C. neoformans GXM. These findings are important because they provide additional evidence for the sharing of antigenically similar components across phylogenetically distant fungal species. Since GXM has been shown to be important for the pathogenesis of C. neoformans and to elicit protective antibodies, the finding of similar molecules in P. brasiliensis raises the possibility that these glycans play similar functions in paracoccidiomycosis. 相似文献