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991.
Susana Silvestre ;Susana de Sousa Araujo ;Maria Carlota Vaz Patto ;Jorge Marques da Silva 《植物学报(英文版)》2014,56(7):610-621
Some species of the Lathyrus genus are among the most promising crops for marginal lands, with high resilience to drought, flood, and fungal diseases, combined with high yields and seed nutritional value. However, lack of knowledge on the mechanisms underlying its outstanding performance and methodologies to identify elite genotypes has hampered its proper use in breeding. Chlorophyl a fast fluorescence transient (JIP test), was used to evaluate water deficit (WD) resistance in Lathyrus genus. Our results reveal unaltered photochemical values for al studied genotypes showing resistance to mild WD. Under severe WD, two Lathyrus sativus genotypes showed remarkable resilience maintaining the photochemical efficiency, contrary to other genotypes studied. Performance index (PIABS) is the best parameter to screen genotypes with improved performance and grain production under WD. Moreover, we found that JIP indices are good indicators of genotypic grain production under WD. Quantum yield of electron transport (wEo) and efficiency with which trapped excitons can move electrons further than QA (c0) revealed as important traits related to improved photosyn-thetic performance and should be exploited in future Lathyrus germplasm improvements. The JIP test herein described showed to be an expeditious tool to screen and to identify elite genotypes with improved drought resistance. 相似文献
992.
Daniela Camargos Costa Gabriela Maíra Pereira de Assis Flávia Alessandra de Souza Silva Flávia Carolina Araújo Júlio César de Souza Junior Zelinda Maria Braga Hirano Flora Satiko Kano Taís Nóbrega de Sousa Luzia Helena Carvalho Cristiana Ferreira Alves de Brito 《PloS one》2015,10(6)
Plasmodium simium is a parasite from New World monkeys that is most closely related to the human malaria parasite Plasmodium vivax; it also naturally infects humans. The blood-stage infection of P. vivax depends on Duffy binding protein II (PvDBPII) and its cognate receptor on erythrocytes, the Duffy antigen receptor for chemokines (hDARC), but there is no information on the P. simium erythrocytic invasion pathway. The genes encoding P. simium DBP (PsDBPII) and simian DARC (sDARC) were sequenced from Southern brown howler monkeys (Alouatta guariba clamitans) naturally infected with P. simium because P. simium may also depend on the DBPII/DARC interaction. The sequences of DBP binding domains from P. vivax and P. simium were highly similar. However, the genetic variability of PsDBPII was lower than that of PvDBPII. Phylogenetic analyses demonstrated that these genes were strictly related and clustered in the same clade of the evolutionary tree. DARC from A. clamitans was also sequenced and contained three new non-synonymous substitutions. None of these substitutions were located in the N-terminal domain of DARC, which interacts directly with DBPII. The interaction between sDARC and PvDBPII was evaluated using a cytoadherence assay of COS7 cells expressing PvDBPII on their surfaces. Inhibitory binding assays in vitro demonstrated that antibodies from monkey sera blocked the interaction between COS-7 cells expressing PvDBPII and hDARC-positive erythrocytes. Taken together, phylogenetic analyses reinforced the hypothesis that the host switch from humans to monkeys may have occurred very recently in evolution, which sheds light on the evolutionary history of new world plasmodia. Further invasion studies would confirm whether P. simium depends on DBP/DARC to trigger internalization into red blood cells. 相似文献
993.
Gabriel C. Grenho L. Cerqueira F. Medeiros R. Dias A. M. Ribeiro A. I. Proença M. F. Fernandes M. H. Sousa J. C. Monteiro F. J. Ferraz M. P. 《Mycopathologia》2019,184(6):775-786
Mycopathologia - Candida can adhere and form biofilm on biomaterials commonly used in medical devices which is a key attribute that enhances its ability to cause infections in humans. Furthermore,... 相似文献
994.
The additional effects of a probiotic mix on abdominal adiposity and antioxidant Status: A double‐blind,randomized trial
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995.
The ultrastructural features and the plastid changes caused by sample preparation were studied in sieve elements of Panicum maximum leaves. Samples of expanded leaves, taken near the ligule region, were fixed and processed by common light and transmission electron microscopy methods. In mature sieve-tube elements, the protoplast is electron-translucent and plastids are the most frequent organelles. Mitochondria and smooth endoplasmic reticulum segments are also visible and occupy a parietal position within the cell. The plastids are globular and show electron-dense proteinaceous inclusions in the stroma. The protein crystals are predominantly cuneate, but thin crystalloids and amorphous and/or filamentous proteins also occur. The presence of intact plastids plus others in different phases of plastid envelope rupture were interpreted as evidence that this rupture is a normal event in response to injury. This plastid envelope rupture is possibly activated by the release of pressure in the sieve-tube element. After plastid membrane vesiculation, the stroma and the protein crystals are dispersed within the sieve-element ground cytoplasm. The vesicles originating from the plastid envelope move to one cell pole, while protein crystalloids move to the opposite pole and agglomerate in the sieve-plate region. Our findings indicate that these protein crystalloids, which deposit in the sieve plate, may act in sieve-plate pores occlusion, preventing the release of phloem sap, similar to the role of P-protein in dicotyledons. 相似文献
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Filipe Brum Machado Fabricio Brum Machado Milena Amendro Faria Viviane Lamim Lovatel Antonio Francisco Alves da Silva Claudia Pamela Radic Carlos Daniel De Brasi álvaro Fabricio Lopes Rios Susana Marina Chuva de Sousa Lopes Leonardo Serafim da Silveira Carlos Ramon Ruiz-Miranda Ester Silveira Ramos Enrique Medina-Acosta 《PloS one》2014,9(7)