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1.
2.
Neuza Domingues André R. A. Marques Rita Diogo Almeida Calado Inês S. Ferreira Cristiano Ramos José Ramalho Maria I. L. Soares Telmo Pereira Luís Oliveira José R. Vicente Louise H. Wong Inês C. M. Simões Teresa M. V. D. Pinho e Melo Andrew Peden Cláudia Guimas Almeida Clare E. Futter Rosa Puertollano Winchil L. C. Vaz Otília V. Vieira 《Traffic (Copenhagen, Denmark)》2023,24(7):284-307
3.
Paulino Bambi Alan M. Tonin Renan de Souza Rezende Fernando Carvalho Vieira Fernanda Gabriela Graciano Miranda Luz Boyero José F. Gonçalves Júnior 《Biotropica》2023,55(1):40-52
Riparian forests play an important role in stream ecosystems, as they support biodiversity, reduce water erosion, and provide litter that fuels aquatic biota. However, they are affected by great array of anthropogenic threats (e.g., fire, logging, and organic pollution), which alter species composition and their physical structure. Although forest recovery after disturbance such as logging can take decades, the legacy of forest clear-cut logging on key processes in tropical riparian ecosystems is mostly unknown. Here, we investigated how litter inputs (leaves, twigs, and reproductive parts) and storage, key processes for carbon and nutrient recycling and for forest and stream biota, are influenced by riparian vegetation undergoing succession (after 28 years from logging) through the comparison of reference and logged forest sites in the Cerrado biome. Litterfall was overall similar between forest types, but litterfall of twigs was twofold higher at logged than reference sites. Similarly, litter inputs from the bank to the stream (i.e., lateral inputs) and streambed storage were 50–60% higher at logged than reference sites. The higher litterfall observed in logged forests could be related to higher proportion of tree species that are characteristic of primary and secondary successional stages, including fast-growing and liana species, which often are more productive and common in anthropogenic areas. Our results showed that the legacy impact of clear-cut logging, even if residual woody vegetation is maintained in riparian buffers, can shift the type, quantity, and seasonality of litter subsidies to tropical streams. This knowledge should be considered within the context of management and conservation of communities and ecosystem processes in the forest-stream interfaces. 相似文献
4.
Lucimar G. Milagres Maria Cristina C. Brandileone Claudio T. Sacchi Vera S.D. Vieira Rosemeire C. Zanella Carl E. Frasch 《FEMS immunology and medical microbiology》1996,13(1):9-17
Abstract Since 1988, N. meningitidis , B:4:P1.15, ET-5 complex, has been responsible for an epidemic of meningococcal disease in Greater São Paulo, Brazil. Despite current trials to develop an effective vaccine against group B meningococci, children less than 2 years old have not been protected. It has been suggested that iron-regulated proteins (IRPs) should be considered as potential antigens for meningococcal vaccines. The vaccines under study consisted of outer-membrane vesicles depleted of lipooligosaccharide from three serogroup B strains and one serogroup C strain, IRPs, meningococcal group C polysaccharide and aluminum hydroxide. Four different protein and C polysaccharide concentrations were studied. The ELISA and bactericidal results showed a higher antibody response when 2 injections of 2.0 μg doses were administered. Despite higher IgG reactivity against antigen preparations containing IRPs seen in ELISA, the bactericidal activity was not increased if the target strain was grown in iron-restricted medium. The influence of addition of alkaline-detoxified lipooligosaccharide (dLOS) on immunogenicity of the vaccine was also investigated, and the dLOS provided for a more functionally specific antibody response. 相似文献
5.
Adolfo H. Mü ller Paulo C. Vieira M. F tima das G.F.da Silva Jo o B. Fernandes 《Phytochemistry》1995,40(6):1797-1800
Two novel dihydrochalcones, 2′,3,4′,6′-tetrahydroxy-4-methoxy-3′,5-di-(3,3-dimethylallyl)-dihydrochalcone and 2′,.3,6′-trihydroxy-4-methoxy-5-(3,3-dimethylallyl)-3′,4′-(2″,2″-dimethyldihydropyran)-dihydrochalcone, have been isolated from fresh fruits of Metrodorea nigra. Stems and leaves showed a similar composition and we have isolated common steroids, simple coumarins, several furocoumarins, furoquinoline alkaloids and a furofuran lignan. From stems, we have also isolated the pentacyclic 6-C-monoterpenyl-5,7-dioxycoumarin, deoxybruceol. Structures of the isolated compounds were elucidated on the basis of spectral data. 相似文献
6.
Christian Biémont Cristina Vieira Christine Hoogland Géraldine Cizeron Catherine Lœvenbruck Claude Arnault Jean-Pierre Carante 《Genetica》1997,100(1-3):161-166
To investigate the main forces controlling the containment of transposable elements (TE) in natural populations, we analyzed
the copia, mdg1, and 412 elements in various populations of Drosophila melanogaster and D. simulans. A lower proportion of
insertion sites on the X chromosome in comparison with the autosomes suggests that selection against the detrimental effects
of TE insertions is the major force containing TE copies in populations of Drosophila. This selection effect hypothesis is
strengthened by the absence of the negative correlation between recombination rate and TE copy number along the chromosomes,
which was expected under the alternative ectopic exchange model (selection against the deleterious rearrangements promoted
by recombination between TE insertions). A cline in 412 copy number in relation to latitude was observed among the natural
populations of D. simulans, with very high numbers existing in some local populations (around 60 copies in a sample from Canberra,
Australia). An apparent absence of selection effects in this Canberra sample and a value of transposition rate equal to 1–2
× 10-3 whatever the population and its copy number agree with the idea of recent but temporarily drastic TE movements in local populations.
The high values of transposition rate in D. simulans clearly disfavor the hypothesis that the low amount of transposable elements
in this species could result from a low transposition rate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
Summary When the Na electrochemical potential difference across the skin (Na) is altered by perturbing the transmembrane electrical potential difference or the external Na concentration, effects on transport and associated oxygen consumption can be described by the formalism of linear nonequilibrium thermodynamics (Vieira, Caplan & Essig, 1972,J. Gen. Physiol.
59:77; Danisi & Lacaz-Vieira, 1974,J. Gen. Physiol.
64:372; Procópio and Lacaz-Vieira, 1977,J. Membrane Biol.
35:219). We now show that with modifications of Na by substitution of Li or choline for Na in the inner bathing solution, this formalism is no longer applicable. Inner Na by K substitution ((Na×K)
i
) causes profound alterations in short-circuit current (SCC),J
Na
in
, K efflux (J
K
eff
) and PD. SCC drops transiently after (Na×K)
i
in Cl and in SO4 media, increasing subsequently. In Cl medium, following the initial transient, there is a late decline in SCC toward a steady state. The rate of SCC decline in Cl medium is more pronounced than that observed in SO4 medium. (Na×K)
i
causes a transient increase inJ
Na
in
with a peak synchronous to the minimum in SCC, both in Cl and in SO4 media. This was interpreted as due to depolarization of the inner membrane. In SO4 medium, following the peak observed after (Na×K)
i
J
Na
in
drops, to increase again toward a steady state in which SCC andJ
Na
in
are not statistically different, resembling the control condition before (Na×K)
i
. In Cl medium, however, theJ
Na
in
steady state is approximately 100% higher than SCC. This difference is due to an important K efflux (J
K
eff
), which builds up progressively after the substitution. The apparent K permeability [J
K
eff
/(K
i
)] is of comparable magnitude in Cl and in SO4 media before (Na×K)
i
, the apparent K permeability increases one order of magnitude as compared to the control condition before the ionic substitution. In Cl medium, the high levels ofJ
Na
in
and ofJ
K
eff
observed in the steady state after (Na×K)
i
were interpreted as being a consequence of cell swelling. SCC and PD follow very different temporal patterns after (Na×K)
i
which are characterized by transients in SCC and a simple fall in PD. Reasons for these differences are discussed. 相似文献
8.
H. Mercier C. C. J. Vieira R. C. L. Figueiredo-Ribeiro 《Plant Cell, Tissue and Organ Culture》1992,28(3):249-254
Leaf and stem segments of Gomphrena officinalis originated from aseptically grown seedlings were used to initiate cultures. Callus production was obtained on gelled Murashige & Skoog medium supplemented with 6-benzylaminopurine alone (1.0, 5.0 or 10.0 mgl-1) or combined with -naphthalene acetic acid (0.1, 0.5 and 1.0 mgl-1) after 10 to 15 days of culture, and can be transferred to fresh medium every 30 days. The combinations of 5.0 or 10.0 mgl-1 of 6-benzylaminopurine with 0.1 mgl-1 of -naphthalene acetic acid were found to be the best for shoot regeneration. Adventitious shoot formation occurred after 50 to 60 days of culture in leaf and internode stem explants. Nodal segments developed actively growing lateral buds after 30 days of culture. Gelled Murashige & Skoog medium containing 10 mgl-1 of indole-3-butyric acid was considered optimal for the rooting of shoots. Rooted plants transferred to potting soil could be successfully established.Abbreviations BA
6-benzylaminopurine
- IAA
indole-3-acetic acid
- IBA
indole-3-butyric acid
- MS
Murashige & Skoog
- NAA
-naphthalene acetic acid 相似文献
9.
W Samuel Fagg Naiyou Liu Ulrich Braunschweig Karen
Larissa Pereira
de
Castro Xiaoting Chen Frederick
S Ditmars Steven
G Widen John Paul Donohue Katalin Modis William
K Russell Jeffrey H Fair Matthew
T Weirauch Benjamin
J Blencowe Mariano
A Garcia-Blanco 《Nucleic acids research》2022,50(9):5313
Alternative splicing is critical for development; however, its role in the specification of the three embryonic germ layers is poorly understood. By performing RNA-Seq on human embryonic stem cells (hESCs) and derived definitive endoderm, cardiac mesoderm, and ectoderm cell lineages, we detect distinct alternative splicing programs associated with each lineage. The most prominent splicing program differences are observed between definitive endoderm and cardiac mesoderm. Integrative multi-omics analyses link each program with lineage-enriched RNA binding protein regulators, and further suggest a widespread role for Quaking (QKI) in the specification of cardiac mesoderm. Remarkably, knockout of QKI disrupts the cardiac mesoderm-associated alternative splicing program and formation of myocytes. These changes arise in part through reduced expression of BIN1 splice variants linked to cardiac development. Mechanistically, we find that QKI represses inclusion of exon 7 in BIN1 pre-mRNA via an exonic ACUAA motif, and this is concomitant with intron removal and cleavage from chromatin. Collectively, our results uncover alternative splicing programs associated with the three germ lineages and demonstrate an important role for QKI in the formation of cardiac mesoderm. 相似文献
10.
Priscilla Cristina Moura Vieira Jersey Heitor da Silva Maus Letícia Martins Lamaro Caroline Aquino Moreira-Nunes Rommel Mrio Rodríguez Burbano 《Current issues in molecular biology》2022,44(5):1838
Our research group, through the analysis of miRNomes in platelet concentrates (PCs) stored in blood banks, identified and validated the miR-127 and miR-320a miRNAs as biomarkers of platelet storage lesions (PSLs) in PCs. In order to validate the miRNAs 127 and 320a methodologically, as PSL biomarkers in a large number of PC bags, we also evaluated important immunological markers involved in the platelet activation/aggregation process—the CD62P receptor (P-selectin), the surface glycoproteins (GP) IIb/IIIa, and the purinergic P2Y12 receptor—via flow cytometry. The miRNAs miR-127 and miR-320a were quantified by real-time quantitative PCR (RT-qPCR). To carry out this study, 500 collection tubes were used at the upper edge of the PC bags containing platelets. Each tube was divided into seven equal parts (totaling 3500 samples) for platelet analysis from 7 different storage days, where the 1st day represents the high-quality control, and the 7th day corresponds to the low-quality control of the platelets. After analyzing all parameters during storage days, it was concluded that the relative quantification of miR-320a below 0.50 and the CD62P receptor below 27.92% are reliable indicators of the absence of storage lesions in blood banks. We believe that the values found in the expression of the CD62P receptor legitimize the use of the miR-320a and miR-127 miRNAs to build a kit capable of accurately measuring whether the stored platelets are suitable for transfusion. 相似文献