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61.
da Silveira Carvalho CP Correia TO Ribeiro SM Silva IC de Oliveira JT Grangeiro TB 《Protein and peptide letters》2006,13(10):1045-1049
Tobacco plants were transformed with gene constructs encoding prepro-ConBr (Canavalia brasiliensis lectin). Transgenic plants confirmed by PCR expressed the recombinant protein as revealed by Western blot. However, the apparent molecular mass of the recombinant polypeptide (ca. 34 kDa) was higher than the native lectin (about 30 kDa), showing that further proteolytic processing of pro-ConBr was not detected. 相似文献
62.
Alexander M. Cardoso Janaína J. V. Cavalcante Maurício E. Cant?o Claudia E. Thompson Roberto B. Flatschart Arnaldo Glogauer Sandra M. N. Scapin Youssef B. Sade Paulo J. M. S. I. Beltr?o Alexandra L. Gerber Orlando B. Martins Eloi S. Garcia Wanderley de Souza Ana Tereza R. Vasconcelos 《PloS one》2012,7(11)
The shortage of petroleum reserves and the increase in CO2 emissions have raised global concerns and highlighted the importance of adopting sustainable energy sources. Second-generation ethanol made from lignocellulosic materials is considered to be one of the most promising fuels for vehicles. The giant snail Achatina fulica is an agricultural pest whose biotechnological potential has been largely untested. Here, the composition of the microbial population within the crop of this invasive land snail, as well as key genes involved in various biochemical pathways, have been explored for the first time. In a high-throughput approach, 318 Mbp of 454-Titanium shotgun metagenomic sequencing data were obtained. The predominant bacterial phylum found was Proteobacteria, followed by Bacteroidetes and Firmicutes. Viruses, Fungi, and Archaea were present to lesser extents. The functional analysis reveals a variety of microbial genes that could assist the host in the degradation of recalcitrant lignocellulose, detoxification of xenobiotics, and synthesis of essential amino acids and vitamins, contributing to the adaptability and wide-ranging diet of this snail. More than 2,700 genes encoding glycoside hydrolase (GH) domains and carbohydrate-binding modules were detected. When we compared GH profiles, we found an abundance of sequences coding for oligosaccharide-degrading enzymes (36%), very similar to those from wallabies and giant pandas, as well as many novel cellulase and hemicellulase coding sequences, which points to this model as a remarkable potential source of enzymes for the biofuel industry. Furthermore, this work is a major step toward the understanding of the unique genetic profile of the land snail holobiont. 相似文献
63.
Sandy Sampaio Videira Michele de Cássia Pereira e Silva Péricles de Souza Galisa Armando Cavalcante Franco Dias Riitta Nissinen Vera Lúcia Baldani Divan Jan Dirk van Elsas José Ivo Baldani Joana Falcão Salles 《Plant and Soil》2013,373(1-2):737-754
Aims
Previous studies have shown that elephant grass is colonized by nitrogen-fixing bacterial species; however, these results were based on culture-dependent methods, an approach that introduces bias due to an incomplete assessment of the microbial community. In this study, we used culture-independent methods to survey the diversity of endophytes and plant-associated bacterial communities in five elephant grass genotypes used in bioenergy production.Methods
The plants of five genotypes of elephant grass were harvested from the experimental area of Embrapa Agrobiologia and divided into stem and root tissues. Total DNA and RNA were extracted from plant tissues and the bacterial communities were analyzed by DGGE and clone library of the 16S rRNA and nifH genes at both the cDNA and DNA levels.Results
Overall, the patterns based on DNA- and RNA-derived DGGE-profiles differed, especially within tissue samples. DNA-based DGGE indicated that both total bacterial and diazotrophic communities associated with roots (rhizoplane?+?endophytes) differed clearly from those obtained from stems (endophytes). These results were confirmed by the phylogenetic analyses of RNA-derived sequences of 16S rRNA (total bacteria; 586 sequences), but not for nifH (186). In fact, rarefaction analyses showed a higher diversity of diazotrophic organisms associated with stems than roots. Based on 16S rRNA sequences, the clone libraries were dominated by sequences affiliated to members of Leptotrix (12.8 %) followed by Burkholderia (9 %) and Bradyrhizobium (6.5 %), while most of the nifH clones were closely related to the genus Bradyrhizobium (26 %).Conclusions
Our results revealed an unexpectedly large diversity of metabolically active bacteria, providing new insights into the bacterial species predominantly found in association with elephant grass. Furthermore, these results can be very useful for the development of new strategies for selection of potential bacteria that effectively contribute to biological nitrogen fixation and enhance the sustainable production of elephant grass as bioenergy crop. 相似文献64.
Lívia Ribeiro Mendon?a Rafael Valente Veiga Vitor Camilo Cavalcante Dattoli Camila Alexandrina Figueiredo Rosemeire Fiaccone Jackson Santos álvaro Augusto Cruz Laura Cunha Rodrigues Philip John Cooper Lain Carlos Pontes-de-Carvalho Maurício Lima Barreto Neuza Maria Alcantara-Neves 《PLoS neglected tropical diseases》2012,6(11)
Background
Toxocara canis and T. cati are parasites of dogs and cats, respectively, that infect humans and cause human toxocariasis. Infection may cause asthma-like symptoms but is often asymptomatic and is associated with a marked eosinophilia. Previous epidemiological studies indicate that T. canis infection may be associated with the development of atopy and asthma.Objectives
To investigate possible associations between Toxocara spp. seropositivity and atopy and childhood wheezing in a population of children living in non-affluent areas of a large Latin American city.Methods
The study was conducted in the city of Salvador, Brazil. Data on wheezing symptoms were collected by questionnaire, and atopy was measured by the presence of aeroallergen-specific IgE (sIgE). Skin prick test (SPT), total IgE and peripheral eosinophilia were measured. Toxocara seropositivity was determined by the presence of anti-Toxocara IgG antibodies, and intestinal helminth infections were determined by stool microscopy.Findings
Children aged 4 to 11 years were studied, of whom 47% were seropositive for anti-Toxocara IgG; eosinophilia >4% occurred in 74.2% and >10% in 25.4%; 59.6% had elevated levels of total IgE; 36.8% had sIgE≥0.70 kU/L and 30.4% had SPT for at least one aeroallergen; 22.4% had current wheezing symptoms. Anti-Toxocara IgG was positively associated with elevated eosinophils counts, total IgE and the presence of specific IgE to aeroallergens but was inversely associated with skin prick test reactivity.Conclusion
The prevalence of Toxocara seropositivity was high in the studied population of children living in conditions of poverty in urban Brazil. Toxocara infection, although associated with total IgE, sIgE and eosinophilia, may prevent the development of skin hypersensitivity to aeroallergens, possibly through increased polyclonal IgE and the induction of a modified Th2 immune reaction. 相似文献65.
Bellizzi D Rose G Cavalcante P Covello G Dato S De Rango F Greco V Maggiolini M Feraco E Mari V Franceschi C Passarino G De Benedictis G 《Genomics》2005,85(2):258-263
SIR2 genes control life span in model organisms, playing a central role in evolutionarily conserved pathways of aging and longevity. We wanted to verify whether similar effects may act in humans too. First, we searched for variability in the human sirtuin 3 gene (SIRT3) and discovered a VNTR polymorphism (72-bp repeat core) in intron 5. The alleles differed both for the number of repeats and for presence/absence of potential regulatory sites. Second, by transient transfection experiments, we demonstrated that the VNTR region has an allele-specific enhancer activity. Third, by analyzing allele frequencies as a function of age in a sample of 945 individuals (20-106 years), we found that the allele completely lacking enhancer activity is virtually absent in males older than 90 years. Thus the underexpression of a human sirtuin gene seems to be detrimental for longevity as it occurs in model organisms. 相似文献
66.
Renata Damásio de Souza Milene Tavares Batista Wilson Barros Luiz Rafael Ciro Marques Cavalcante Jaime Henrique Amorim Raíza Sales Pereira Bizerra Eduardo Gimenes Martins Luís Carlos de Souza Ferreira 《PloS one》2014,9(1)
Bacillus subtilis spores have received growing attention regarding potential biotechnological applications, including the use as probiotics and in vaccine formulations. B. subtilis spores have also been shown to behave as particulate vaccine adjuvants, promoting the increase of antibody responses after co-administration with antigens either admixed or adsorbed on the spore surface. In this study, we further evaluated the immune modulatory properties of B. subtilis spores using a recombinant HIV gag p24 protein as a model antigen. The adjuvant effects of B. subtilis spores were not affected by the genetic background of the mouse lineage and did not induce significant inflammatory or deleterious effects after parenteral administration. Our results demonstrated that co-administration, but not adsorption to the spore surface, enhanced the immunogenicity of that target antigen after subcutaneous administration to BALB/c and C57BL/6 mice. Spores promoted activation of antigen presenting cells as demonstrated by the upregulation of MHC and CD40 molecules and enhanced secretion of pro-inflammatory cytokines by murine dendritic cells. In addition, in vivo studies indicated a direct role of the innate immunity on the immunomodulatory properties of B. subtilis spores, as demonstrated by the lack of adjuvant effects on MyD88 and TLR2 knockout mouse strains. 相似文献
67.
Cavalcante Thiago Strier Karen B. Bicca-Marques Júlio César 《International journal of primatology》2021,42(4):533-547
International Journal of Primatology - The main factors influencing feeding competition among members of diurnal primate groups are the distribution, availability, and quality of food resources.... 相似文献
68.
Bruno Frederico Aguilar Calegare Augusto Azzolini Julia Ribeiro da Silva Vallim Edson Guimares Lo Turco Priscila Farias Tempaku Vanessa Cavalcante da Silva Sergio Tufik Vnia D'Almeida 《Genesis (New York, N.Y. : 2000)》2020,58(3-4)
A previous animal study by our group found that sleep deprivation during preimplantation was associated with decreased pregnancy maintenance. Given its impact on human society, we aimed in the current study to assess whether sleep deprivation affects blastocyst gene expression and/or the implantation process. For this, pregnant mice (gestational day 0 [GD 0]) were assigned into paradoxical sleep deprivation (SD, 72 hr; multiple platform method) and, a control (CT) group. Animals were euthanized on GD 3.5 and blood, uterus (embryos) and fallopian tube were collected. Then, 89% of CT presented blastocysts in the uterus versus 25% from SD group. Compared to CT, SD presented lighter relative uterus weight, increased plasma concentrations of corticosterone and testosterone, decreased concentrations of progesterone and luteinizing hormone, but no statistical differences in plasma concentrations of 17β‐estradiol and follicle stimulating hormone. There were no differences in uterus and blastocyst gene expression related to embryo implantation and development, and no alteration in blastocysts global DNA methylation. Considering this, the decreased pregnancy maintenance after sleep deprivation seems not to be associated with implantation losses or developmental problems related to the blastocysts. It is likely that complications in morula development and/or its movement through the fallopian tubes affect the pregnancy rate, since only 25% of SD females presented a blastocyst on the GD 3.5. In fact, three out of four females without blastocysts in the uterus presented morula in the fallopian tubes due to a phase delay. Additionally, we suggest that the observed hormonal changes may play a role in this outcome. 相似文献
69.
70.
Litia A. Carvalho Louise C. Vitorino Roberta P.M. Guimarães Silvana Allodi Ricardo A. de Melo Reis Leny A. Cavalcante 《Biochemical and biophysical research communications》2014
We examined the effects of conditioned medium from olfactory ensheathing glia (OEGCM) on the differentiation of oligodendrocytes in mixed cultures of early postnatal hippocampi. Differentiation was judged from the numerical density (ND) of cells immunoreactive to 2′3′ cyclic nucleotide 3′phosphodiesterase (CNPase) and O4 antibodies. NDs increased according to inverted-U dose–response curves, particularly for CNPase+ cells (9-fold at optimal dilution) and these changes were blocked by inhibitors of ERK1, p38-MAPK, and PI3K. Our results raise the possibility that OEG secreted factor(s) may counteract demyelination induced by trauma, neurodegenerative diseases, and advanced age, and should stimulate novel methods to deliver these factors and/or potentiating chemicals. 相似文献