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81.
Adones Sales Luana Ferreira Afonso Juliana Alves Americo Mauro de Freitas Rebelo Glaucia Maria Pastore Juliano Lemos Bicas 《Biotechnology letters》2018,40(3):561-567
Objective
To investigate the biocatalytic potential of Colletotrichum acutatum and Colletotrichum nymphaeae for monoterpene biotransformation.Results
C. acutatum and C. nymphaeae used limonene, α-pinene, β-pinene, farnesene, citronellol, linalool, geraniol, perillyl alcohol, and carveol as sole carbon and energy sources. Both species biotransformed limonene and linalool, accumulating limonene-1,2-diol and linalool oxides, respectively. α-Pinene was only biotransformed by C. nymphaeae producing campholenic aldehyde, pinanone and verbenone. The biotransformation of limonene by C. nymphaeae yielded 3.34–4.01 g limonene-1,2-diol l?1, depending on the substrate (R-(+)-limonene, S-(?)-limonene or citrus terpene (an agro-industrial by-product). This is among the highest concentrations already reported for this product.Conclusions
This is the first report on the biotransformation of these terpenes by Colletotrichum spp. and the biotransformation of limonene to limonene-1,2-diol possibly involves enzymes similar to those found in Grosmannia clavigera.82.
Lorenna Alves Mattos-Moreira Claudia Fortes Ferreira Edson Perito Amorim Carlos Priminho Pirovani Edson Mario de Andrade Mauricio Antônio Coelho Filho Carlos Alberto da Silva Ledo 《Acta Physiologiae Plantarum》2018,40(3):60
Bananas are one of the most important fruits in tropical and subtropical regions worldwide. Each year, banana plantations expand, but the areas available are mostly dry lands. The establishment of strategies for obtaining drought tolerant cultivars depends on understanding of biological responses at genetic, molecular and biochemical levels. Proteomics is a powerful tool for functional characterization of the response of plants to abiotic stress and little is known about drought tolerance in Musa spp. Therefore, the aim of this study was to identify proteins related to drought tolerance in two contrasting banana genotypes, Prata Anã and BRS Tropical, susceptible and tolerant to drought, respectively. Proteins were extracted from rhizomes of bananas grown under greenhouse conditions with control, irrigated and water deficit regimes. The differential protein expression pattern was established by two-dimensional (2-D) electrophoresis and spots analyzed in nano Q-Tof Micro UPLC. Twenty-three differentially expressed proteins were found in the tolerant genotype (BRS Tropical) under water deficit, with proteins involved in metabolism, defense and transport. Proteins were classified according to known function and biosynthetic pathways. Signaling proteins in response to water stress, especially for the biological function of growth and development of plants cells, were also encountered, whereas heat shock proteins played a significant role. This is the first report of proteomic analysis for drought tolerance in ‘Pome’ and ‘Silk-type’ bananas containing the ‘B’ genome. Our work provides insights into Musa spp. response to drought and data for further studies regarding molecular mechanisms, which determine how Musa spp. cells better overcome environmental perturbations. 相似文献
83.
Marcos Valerio Garcia Vinicius da Silva Rodrigues Antônio Carlos Monteiro Lucas Detogni Simi Leandro de Oliveira Souza Higa Maria Marlene Martins Nancy Prette Dinalva Alves Mochi Renato Andreotti Matias Pablo Juan Szabó 《Experimental & applied acarology》2018,76(4):507-512
Amblyomma parvum Aragão (Acari: Ixodidae) is a tick species found with wide distribution in the Neotropical region. Even though it is a wildlife-related tick, it is also a frequent parasite of domestic animals, is aggressive to human beings and may harbor pathogenic microorganisms. Therefore, it is a target species for control on domestic animals, particularly those at the rural–wildlife interface. Herein, the efficacy of two isolates (E9 and IBCB 425) of an entomopathogenic fungus, Metarhizium anisopliae sensu lato, already evaluated for ticks that parasitize domestic animals, was tested against unfed A. parvum adults. Both isolates displayed high acaricidal efficacy after immersion in fungal conidial suspensions for 5 min. Isolate E9 killed all ticks by the 7th day post-treatment, and isolate IBCB 425 did so by the 11th day. Tick mortality of 80 and 90% was achieved as early as the 3rd and 4th days, respectively, with both treatments. Thus, if a commercial M. anisopliae s.l. acaricide against domestic animal ticks is developed, it would also be effective against A. parvum. 相似文献
84.
Paulo Eduardo Menezes‐Silva Lucas Loram‐Loureno Rauander Douglas Ferreira Barros Alves Letícia Ferreira Sousa Sabrina Emanuella da Silva Almeida Fernanda Santos Farnese 《Ecology and evolution》2019,9(20):11979-11999
Anthropogenic activities such as uncontrolled deforestation and increasing greenhouse gas emissions are responsible for triggering a series of environmental imbalances that affect the Earth's complex climate dynamics. As a consequence of these changes, several climate models forecast an intensification of extreme weather events over the upcoming decades, including heat waves and increasingly severe drought and flood episodes. The occurrence of such extreme weather will prompt profound changes in several plant communities, resulting in massive forest dieback events that can trigger a massive loss of biodiversity in several biomes worldwide. Despite the gravity of the situation, our knowledge regarding how extreme weather events can undermine the performance, survival, and distribution of forest species remains very fragmented. Therefore, the present review aimed to provide a broad and integrated perspective of the main biochemical, physiological, and morpho‐anatomical disorders that may compromise the performance and survival of forest species exposed to climate change factors, particularly drought, flooding, and global warming. In addition, we also discuss the controversial effects of high CO2 concentrations in enhancing plant growth and reducing the deleterious effects of some extreme climatic events. We conclude with a discussion about the possible effects that the factors associated with the climate change might have on species distribution and forest composition. 相似文献
85.
Fernando H. F. Alves Carlos C. Crestani Leonardo B. M. Resstel Fernando M. A. Corrêa 《PloS one》2014,9(1)
The insular cortex (IC) is a limbic structure involved in cardiovascular responses observed during aversive threats. However, the specific neurotransmitter mediating IC control of cardiovascular adjustments to stress is yet unknown. Therefore, in the present study we investigated the role of local IC adrenoceptors in the cardiovascular responses elicited by acute restraint stress in rats. Bilateral microinjection of different doses (0.3, 5, 10 and 15 nmol/100 nl) of the selective α1-adrenoceptor antagonist WB4101 into the IC reduced both the arterial pressure and heart rate increases elicited by restraint stress. However, local IC treatment with different doses (0.3, 5, 10 and 15 nmol/100 nl) of the selective α2-adrenoceptor antagonist RX821002 reduced restraint-evoked tachycardia without affecting the pressor response. The present findings are the first direct evidence showing the involvement of IC adrenoceptors in cardiovascular adjustments observed during aversive threats. Our findings indicate that IC noradrenergic neurotransmission acting through activation of both α1- and α2-adrenoceptors has a facilitatory influence on pressor response to acute restraint stress. Moreover, IC α1-adrenoceptors also play a facilitatory role on restraint-evoked tachycardiac response. 相似文献
86.
Mara S. Roset Andrés E. Iba?ez Job Alves de Souza Filho Juan M. Spera Leonardo Minatel Sergio C. Oliveira Guillermo H. Giambartolomei Juliana Cassataro Gabriel Briones 《PloS one》2014,9(7)
Brucella, the etiological agent of animal and human brucellosis, is a bacterium with the capacity to modulate the inflammatory response. Cyclic β-1,2-glucan (CβG) is a virulence factor key for the pathogenesis of Brucella as it is involved in the intracellular life cycle of the bacteria. Using comparative studies with different CβG mutants of Brucella, cgs (CβG synthase), cgt (CβG transporter) and cgm (CβG modifier), we have identified different roles for this polysaccharide in Brucella. While anionic CβG is required for bacterial growth in low osmolarity conditions, the sole requirement for a successful Brucella interaction with mammalian host is its transport to periplasmic space. Our results uncover a new role for CβG in promoting splenomegaly in mice. We showed that CβG-dependent spleen inflammation is the consequence of massive cell recruitment (monocytes, dendritics cells and neutrophils) due to the induction of pro-inflammatory cytokines such as IL-12 and TNF-α and also that the reduced splenomegaly response observed with the cgs mutant is not the consequence of changes in expression levels of the characterized Brucella PAMPs LPS, flagellin or OMP16/19. Complementation of cgs mutant with purified CβG increased significantly spleen inflammation response suggesting a direct role for this polysaccharide. 相似文献
87.
Maranhão Fernanda Cristina de Albuquerque Mendonça Nayara Maciel Teixeira Thamires Costa Lages Gilvonete Alves da Costa Sobrinha de Melo Jacqueline Araújo Porciuncula Carlos Guilherme Gaelzer da Silva Filho Eurípedes Alves Silva Denise Maria Wanderlei 《Mycopathologia》2020,185(3):537-543
Mycopathologia - Candida species are common in the human oral microbiota and may cause oral candidiasis (OC) when the microbiota equilibrium is disturbed. Immunosuppressed individuals are... 相似文献
88.
Adriano de Paula Sabino Daniel Dias Ribeiro Caroline Pereira Domingheti Danyelle Romana Alves Rios Luci Maria SantAna Dusse Maria das Graças Carvalho Ana Paula Fernandes 《Molecular biology reports》2014,41(3):1771-1777
Recent studies have demonstrated association between ABO blood system and thrombosis, indicating that individuals belonging to non-O blood groups (A, B or AB) present an increased risk of venous thrombosis, heart disease, and ischemic stroke (IS) as compared to O blood group carriers. In this study, we investigated the frequency of ABO blood group polymorphisms and its association with IS and peripheral arterial disease. Significant differences were observed for O1 (OR 0.57, 95 % CI 0.35–0.95, p < 0.05) and O2 (OR 3.47, 95 % CI 1.15–10.28, p < 0.05) alleles among IS patients while significant differences were observed for B phenotype (26.3 vs 9.5 %, OR 3.42, 95 % CI 1.32–8.76, p = 0.01, patients vs controls, respectively) and alleles A1 (OR 0.31, 95 % CI 0.11–0.84, p < 0.05), O2 (OR 4.61, 95 % CI 1.59–13.23, p < 0.01) and B (OR 3.42, 95 % CI 1.62–7.13, p < 0.001) alleles for PAD patients. O1 allele was an independent variable (OR 0.27, 95 % CI 0.12–0.57, p < 0.001) for IS patients. These data suggest the relationship of non-O blood groups in pathogenesis of thrombosis events and a possible protective effect of O blood group. 相似文献
89.
Jose Eduardo U. Rojas Barbara B. Gerbelli Anderson O. Ribeiro Iseli L. Nantes-Cardoso Francesca Giuntini Wendel A. Alves 《Biopolymers》2019,110(2):e23245
In this study, we prepared translucid hydrogels with different concentrations of silk fibroin, extracted from raw silk fibers, and used them as a matrix to incorporate the photosensitizer 5-(4-aminophenyl)-10,15,20-tris-(4-sulphonatophenyl) porphyrin trisodium for application in photodynamic therapy (PDT). The hydrogels obtained were characterized by rheology, spectrophotometry, and scattering techniques to elucidate the factors involved in the formation of the hydrogel, and to characterize the behavior of silk fibroin (SF) after incorporating of the porphyrin to the matrix. The rheology results demonstrated that the SF hydrogels had a shear thinning behavior. In addition, we were able to verify that the structure of the material was able to be recovered over time after shear deformation. The encapsulation of porphyrins in hydrogels leads to the formation of self-assembled peptide nanostructures that prevent porphyrin aggregation, thereby greatly increasing the generation of singlet oxygen. Also, our findings suggest that porphyrin can diffuse out of the hydrogel and permeate the outer skin layers. This evidence suggests that SF hydrogels could be used as porphyrin encapsulation and as a drug carrier for the sustained release of photosensitizers for PDT. 相似文献
90.
Prenatal diagnosis of familial amyloidotic polyneuropathy: evidence for an early expression of the associated transthyretin methionine 30 总被引:3,自引:0,他引:3
Maria Rosário Almeida Isabel Longo Alves Yoshiuki Sakaki Pedro Pinho Costa Maria João M. Saraiva 《Human genetics》1990,85(6):623-626
Summary Transthyretin methionine 30 (TTR Met 30), which is associated with familial amyloidotic polyneuropathy, originates in a single base substitution (A for G) in the second exon of the TTR gene. This autosomal dominant disease can be diagnosed by RFLP analysis of NsiI-digested DNA. The amplification of DNA by PCR improves the diagnosis method, making it suitable for prenatal diagnosis. Using PCR-amplified DNA, prenatal diagnosis of two at-risk fetuses was performed. Control Met 30 and normal DNA (either genomic or produced by site directed mutagenesis) were processed in parallel. The diagnosis was made by hybridization with allele-specific oligonucleotide probes, and later confirmed by screening of the mutant protein in the amniotic fluid and, when possible, in the sera from the newborns. TTR Met 30 was detected in the amniotic fluid of a positive fetus whose father was the carrier of the mutation. This indicates that the mutant protein is expressed very early in development. 相似文献