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911.
Márcia Cristina Ribeiro Andrade José Paulo Gagliardi Leite & Pedro Hernan Cabello 《Journal of medical primatology》2009,38(1):39-41
Background Rhesus monkeys are relevant models for human diseases. The simian immunodeficiency virus (SIV) infection is an useful macaque model for assessing human immunodeficiency virus (HIV) vaccine strategies. Susceptibility and resistance to viruses have been associated with particular major histocompatibility complex (MHC) molecules. Several epitopes in the HIV structural and non-structural protein restricted by distinct MHC class I haplotypes are important targets for human cytotoxic T lymphocytes, which mediate protection against SIVmac infection. Mamu-A*01 , for example, is a MHC class I molecule of rhesus monkeys that presents a peptide from SIV gag protein.
Methods Our study determined the frequency of Mamu-A*01 in a closed colony of rhesus monkeys from Brazil by polymerase chain reaction.
Results A high frequency of the allele was found in the study colony.
Conclusion This colony provides a significant source of A*01 -positive animals to investigators. 相似文献
Methods Our study determined the frequency of Mamu-A*01 in a closed colony of rhesus monkeys from Brazil by polymerase chain reaction.
Results A high frequency of the allele was found in the study colony.
Conclusion This colony provides a significant source of A*01 -positive animals to investigators. 相似文献
912.
Summary A new monotypic genus and a new species of Monimiaceae, Grazielanthus arkeocarpus from the Brazilian Atlantic coastal forest are described, illustrated and compared with morphologically related taxa. The
new taxon occurs in the State of Rio de Janeiro in the central coastal plain and was collected in the Po?o das Antas Biological
Reserve, municipality of Silva Jardim (22°30′– 22°33′S; 42°14′– 42°19′W). The new taxon is represented by dioecious climbing
shrubs of the sub-canopy that have urceolate, four-lobed flowers and a fleshy hypanthium that is closed until the fruit ripens.
When ripe, the hypanthium ruptures irregularly and the fruitlets are exposed. The relationships between the new genus and
other neotropical (Hennecartia J. Poiss. and Macrotorus Perkins) and paleotropical (Palmeria F. Muell.) genera are discussed. 相似文献
913.
Varaldo PB Miyaji EN Vilar MM Campos AS Dias WO Armôa GR Tendler M Leite LC McIntosh D 《FEMS immunology and medical microbiology》2006,48(1):132-139
A mycobacterial codon-optimized gene encoding the Sm14 antigen of Schistosoma mansoni was generated using oligonucleotide assembly. This synthetic gene enhanced approximately fourfold the protein expression level in recombinant Mycobacterium bovis Bacille Calmette-Guérin (rBCG) when compared to that obtained using the native gene in the same expression vector. Immunization of mice with rBCG expressing Sm14 via the synthetic gene induced specific cellular Th1-predominant immune responses, as determined by interferon-gamma production of Sm14-stimulated splenocytes, which were comparable to those recorded in animals immunized with an rBCG strain expressing the native gene. Administration of a single dose of the rBCG-Sm14 construct carrying the synthetic gene conferred protection against cercarial challenge in outbred Swiss mice, at a level equivalent to those provided by either a single dose of rBCG expressing the native gene or three doses of Escherichia coli-derived recombinant Sm14. Our data demonstrated that despite improving the level of antigen expression, the codon optimization strategy did not result in enhanced immunity or protection against cercarial S. mansoni challenge. 相似文献
914.
Luciola Santos Lannes Harry Olde Venterink Matheus Roberto Leite Jaqueline Nascimento Silva Martina Oberhofer 《Ecology and evolution》2020,10(13):6364-6372
Nutrients are known to limit productivity of plant communities around the world. In the Brazilian Cerrado, indirect evidences point to phosphorus as the main limiting nutrient, but some fertilization experiments suggest that one or more micronutrients might play this role. Boron is one of the essential micronutrients for plants. Agronomically, it received some attention, but it has mostly been neglected in ecological studies assessing the effects of nutrients on plant growth. Through field fertilization and mesocosm experiments in a degraded area in the Cerrado, we show that boron addition increased biomass production of herbaceous vegetation. This could be related to a lower aluminum uptake in the boron fertilized plants. Even considering that plant growth was promoted by boron addition due to aluminum toxicity alleviation, this is the first study reporting boron limitation in natural, noncultivated plant communities and also the first report of this kind in vegetative grasses. These results contribute to disentangling patterns of nutrient limitation among plant species of the species‐rich, aluminum‐rich, and nutrient‐poor Cerrado biome and highlight the potential role of micronutrients, such as boron, for growth of noncrop plants. Understanding how nutrient limitation differs among functional groups in the highly biodiverse areas founded on ancient tropical soils may help managing these plant communities in a changing world. 相似文献
915.
da Silva Junior HC da Silva E Mouta Junior S de Mendonça MC de Souza Pereira MC da Rocha Nogueira A de Azevedo ML Leite JP de Moraes MT 《Biotechnology letters》2012,34(9):1623-1627
The VP6 protein of rotavirus A (RVA) is a target antigen used for diagnostic assays and also for the development of new RVA vaccines. We have compared the expression of VP6 protein in human embryonic kidney (HEK293-T) cells with results obtained using a well-established insect cell-baculovirus system. The recombinant VP6 (rVP6) expressed in HEK293-T cells did not present degradation and also retained the ability to form trimers. In the insect cell-baculovirus system, rVP6 was expressed at higher levels and with protein degradation as well as partial loss of ability to form trimers was observed. Therefore, HEK293-T cells represent a less laborious alternative system than insect cells for expression of rVP6 from human RVA. 相似文献
916.
917.
Antonio Carlos Augusto da Costa Selma Gomes Ferreira Leite 《Biotechnology letters》1991,13(8):559-562
Summary Cadmium and zinc biosorption, alone or in combination, was investigated with sodium alginate immobilizedChlorella homosphaera cells. Concentrations ranging from 20.0 to 41.0mg/l cadmium, 75.0 and 720.0mg/l zinc were tested and, in all cases, the metal removal achieved values near 100%. When these metals were put in combination a decrease in the rate of absorption was detected. Gold was also tested in the immobilized system and 90% of the initial metal added was recovered in a solution containing 213.0mg/l of the metal, the alginic matrix being responsible for 40% gold uptake. 相似文献
918.
919.
Production of rhamnolipids and diesel oil degradation by bacteria isolated from soil contaminated by petroleum 下载免费PDF全文
Giuseppe G. F. Leite Juciane V. Figueirôa Thiago C. M. Almeida Jaqueline L. Valões Walber F. Marques Maria D. D. C. Duarte Krystyna Gorlach‐Lira 《Biotechnology progress》2016,32(2):262-270
Biosurfactants are microbial secondary metabolites. The most studied are rhamnolipids, which decrease the surface tension and have emulsifying capacity. In this study, the production of biosurfactants, with emphasis on rhamnolipids, and diesel oil degradation by 18 strains of bacteria isolated from waste landfill soil contaminated by petroleum was analyzed. Among the studied bacteria, gram‐positive endospore forming rods (39%), gram positive rods without endospores (17%), and gram‐negative rods (44%) were found. The following methods were used to test for biosurfactant production: oil spreading, emulsification, and hemolytic activity. All strains showed the ability to disperse the diesel oil, while 77% and 44% of the strains showed hemolysis and emulsification of diesel oil, respectively. Rhamnolipids production was observed in four strains that were classified on the basis of the 16S rRNA sequences as Pseudomonas aeruginosa. Only those strains showed the rhlAB gene involved in rhamnolipids synthesis, and antibacterial activity against Escherichia coli, P. aeruginosa, Staphylococcus aureus, Bacillus cereus, Erwinia carotovora, and Ralstonia solanacearum. The highest production of rhamnolipids was 565.7 mg/L observed in mineral medium containing olive oil (pH 8). With regard to the capacity to degrade diesel oil, it was observed that 7 strains were positive in reduction of the dye 2,6‐dichlorophenolindophenol (2,6‐DCPIP) while 16 had the gene alkane mono‐oxygenase (alkB), and the producers of rhamnolipids were positive in both tests. Several bacterial strains have shown high potential to be explored further for bioremediation purposes due to their simultaneous ability to emulsify, disperse, and degrade diesel oil. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 32:262–270, 2016 相似文献
920.
Sílvia Fontenete Marina Leite Davie Cappoen Rita Santos Chris Van Ginneken Céu Figueiredo Jesper Wengel Paul Cos Nuno Filipe Azevedo 《PloS one》2016,11(2)