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21.
Laëtitia Coudray Renata Marcia de Figueiredo Stéphanie Duez Sylvie Cortial 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):972-985
With the aim of creating new bisubstrate inhibitors of protein farnesyltransferase (FTase), new carboxylic farnesyl pyrophosphate analogues have been designed and synthesized. The original structures are built around three elements: a prenyl moiety, a 1,4-diacid motif and an imidazole ring. All the compounds were evaluated for their ability to inhibit FTase and compared with the corresponding derivatives lacking the imidazole ring, synthesized for that purpose. These new compounds are not bisubstrate inhibitors probably because the imidazole ring is not in the right position to interact with the zinc atom. However these derivatives display FPP competitive inhibition with a good activity in the carboxylic farnesyl pyrophosphate analogues series. 相似文献
22.
E.G. Santos F.G.P. Costa J.H.V. Silva T.D.D. Martins D.F. Figueiredo‐Lima M. Macari C.J.B. Oliveira P.E.N. Givisiez 《Journal of applied microbiology》2013,114(4):1158-1165
Aims
To evaluate mannan oligosaccharide (MOS) and threonine effects on performance, small intestine morphology and Salmonella spp. counts in Salmonella Enteritidis‐challenged birds.Methods and Results
One‐day‐old chicks (1d) were distributed into five treatments: nonchallenged animals fed basal diet (RB‐0), animals fed basal diet and infected with Salmonella Enteritidis (RB‐I), animals fed high level of threonine and infected (HT‐I), birds fed basal diet with MOS and infected (MOS‐I), birds fed high level of threonine and MOS and infected (HT+MOS‐I). Birds were inoculated at 2d with Salmonella Enteritidis, except RB‐0 birds. Chicks fed higher dietary threonine and MOS showed performance similar to RB‐0 and intestinal morphology recovery at 8 dpi. Salmonella counts and the number of Salmonella‐positive animals were lower in HT+MOS‐I compared with other challenged groups.Conclusion
Mannan oligosaccharides and threonine act synergistically, resulting in improved intestinal environment and recovery after Salmonella inoculation.Significance and Impact of the Study
Nutritional approaches may be useful to prevent Salmonella infection in the first week and putative carcass contamination at slaughter. This is the first report on the possible synergistic effect of mannan oligosaccharides and threonine, and further studies should be performed including performance, microbiota evaluation, composition of intestinal mucins and immune assessment. 相似文献23.
Carola E. Bunse Sylvia Borchers Pavankumar R. Varanasi Sabine Tischer Constan?a Figueiredo Stephan Immenschuh Ulrich Kalinke Ulrike K?hl Lilia Goudeva Britta Maecker-Kolhoff Arnold Ganser Rainer Blasczyk Eva M. Weissinger Britta Eiz-Vesper 《PloS one》2013,8(12)
Adoptive transfer of antiviral T cells enhances immune reconstitution and decreases infectious complications after stem cell transplantation. Information on number and function of antiviral T cells in stem cell grafts is scarce. We investigated (1) immunomodulatory effects of G-CSF on antiviral T cells, (2) the influence of apheresis, and (3) the optimal time point to collect antiviral cells.CMV-, EBV- and ADV-specific T cells were enumerated in 170 G-CSF-mobilized stem cell and 24 non-mobilized platelet donors using 14 HLA-matched multimers. T-cell function was evaluated by IFN-γ ELISpot and granzyme B secretion. Immunophenotyping was performed by multicolor flow cytometry.G-CSF treatment did not significantly influence frequency of antiviral T cells nor their in vitro expansion rate upon antigen restimulation. However, T-cell function was significantly impaired, as expressed by a mean reduction in secretion of IFN-γ (75% in vivo, 40% in vitro) and granzyme B (32% target-independent, 76% target-dependent) as well as CD107a expression (27%). Clinical follow up data indicate that the first CMV-reactivation in patients and with it the need for T-cell transfer occurs while the donor is still under the influence of G-CSF.To overcome these limitations, T-cell banking before mobilization or recruitment of third party donors might be an option to optimize T-cell production. 相似文献
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25.
Rocha Vanesca Priscila Camargo Gonçalves-Vidigal Maria Celeste Ortiz Alex Henrique Tiene Valentini Giseli Ferreira Rebecca Caroline Ulbricht Gonçalves Tiago Maretti Lacanallo Giselly Figueiredo Vidigal Filho Pedro Soares 《Plant Molecular Biology Reporter》2020,38(1):25-38
Plant Molecular Biology Reporter - Manihot esculenta Crantz is originally from the Amazon region of Brazil, which has the highest genetic diversity. Due to the wide adaptation of cassava to the... 相似文献
26.
Nívea?Dias Amoêdo Juan?Perez Valencia Mariana?Figueiredo Rodrigues Antonio Galina Franklin?David Rumjanek 《Bioscience reports》2013,33(6)
Tumour cells thrive in environments that would be hostile to their normal cell counterparts. Survival depends on the selection of cell lines that harbour modifications of both, gene regulation that shifts the balance between the cell cycle and apoptosis and those that involve the plasticity of the metabolic machinery. With regards to metabolism, the selected phenotypes usually display enhanced anaerobic glycolysis even in the presence of oxygen, the so-called Warburg effect, and anabolic pathways that provide precursors for the synthesis of lipids, proteins and DNA. The review will discuss the original ideas of Otto Warburg and how they initially led to the notion that mitochondria of tumour cells were dysfunctional. Data will be presented to show that not only the organelles are viable and respiring, but that they are key players in tumorigenesis and metastasis. Likewise, interconnecting pathways that stand out in the tumour phenotype and that require intact mitochondria such as glutaminolysis will be addressed. Furthermore, comments will be made as to how the peculiarities of the biochemistry of tumour cells renders them amenable to new forms of treatment by highlighting possible targets for inhibitors. In this respect, a case study describing the effect of a metabolite analogue, the alkylating agent 3BP (3-bromopyruvate), on glycolytic enzyme targets will be presented. 相似文献
27.
28.
Rosane Dias Costa Vanessa Amaral Mendon?a Frederico Marianetti Soriani Sandra Lyon Rachel Adriana Penido Ana Maria Duarte Dias Costa Marina Dias Costa Fabio de Souza Terra Mauro Martins Teixeira Carlos Mauricio de Figueiredo Antunes Antonio Lúcio Teixeira 《Memórias do Instituto Oswaldo Cruz》2013,108(8):1051-1056
Leprosy is an infectious and contagious spectral disease accompanied by a series of
immunological events triggered by the host response to the aetiologic agent,
Mycobacterium leprae . The induction and maintenance of the
immune/inflammatory response in leprosy are linked to multiple cell interactions and
soluble factors, primarily through the action of cytokines. The purpose of the
present study was to evaluate the serum levels of tumour necrosis factor (TNF)-α and
its soluble receptors (sTNF-R1 and sTNF-R2) in leprosy patients at different stages
of multidrug treatment (MDT) in comparison with non-infected individuals and to
determine their role as putative biomarkers of the severity of leprosy or the
treatment response. ELISA was used to measure the levels of these molecules in 30
healthy controls and 37 leprosy patients at the time of diagnosis and during and
after MDT. Our results showed increases in the serum levels of TNF-α and sTNF-R2 in
infected individuals in comparison with controls. The levels of TNF-α, but not
sTNF-R2, decreased with treatment. The current results corroborate previous reports
of elevated serum levels of TNF-α in leprosy and suggest a role for sTNF-R2 in the
control of this cytokine during MDT. 相似文献
29.
Jaqueline Raymondi Silva Larissa Campos de Medeiros Vinícius Pinho dos Reis Juliana Helena Chávez Thiago Demarchi Munhoz Gustavo Puia Borges Otavio Augusto Brioschi Soares Carlos Henrique Coelho de Campos Rosangela Zacarias Machado Cristiane Divan Baldani Maria Luana Cristiny Rodrigues Silva Joice Lara Maia Faria Edson Elias da Silva Luiz Tadeu Moraes Figueiredo 《Memórias do Instituto Oswaldo Cruz》2013,108(7):921-923
Since the emergence of West Nile virus (WNV) in North America in 1999, there have been several reports of WNV activity in Central and South American countries. To detect WNV in Brazil, we performed a serological survey of horses from different regions of Brazil using recombinant peptides from domain III of WNV. Positive samples were validated with the neutralisation test. Our results showed that of 79 ELISA-positive horses, nine expressed WNV-specific neutralising antibodies. Eight of the infected horses were from the state of Mato Grosso do Sul and one was from the state of Paraíba. Our results provide additional evidence for the emergence of WNV in Brazil and for its circulation in multiple regions of the country. 相似文献
30.
Daniela Volcan Almeida Camila de Martinez Gaspar Martins M��rcio de Azevedo Figueiredo Carlos Frederico Ceccon Lanes Adalto Bianchini Luis Fernando Marins 《Transgenic research》2013,22(1):75-88
Growth hormone (GH) transgenic fish are at a critical step for possible approval for commercialization. Since this hormone is related to salinity tolerance in fish, our main goal was to verify whether the osmoregulatory capacity of the stenohaline zebrafish (Danio rerio) would be modified by GH-transgenesis. For this, we transferred GH-transgenic zebrafish (T) from freshwater to 11 ppt salinity and analyzed survival as well as relative changes in gene expression. Results show an increased mortality in T versus non-transgenic (NT) fish, suggesting an impaired mechanism of osmotic acclimation in T. The salinity effect on expression of genes related to osmoregulation, the somatotropic axis and energy metabolism was evaluated in gills and liver of T and NT. Genes coding for Na+, K+-ATPase, H+-ATPase, plasma carbonic anhydrase and cytosolic carbonic anhydrase were up-regulated in gills of transgenics in freshwater. The growth hormone receptor gene was down-regulated in gills and liver of both NT and T exposed to 11 ppt salinity, while insulin-like growth factor-1 was down-regulated in liver of NT and in gills of T exposed to 11 ppt salinity. In transgenics, all osmoregulation-related genes and the citrate synthase gene were down-regulated in gills of fish exposed to 11 ppt salinity, while lactate dehydrogenase expression was up-regulated in liver. Na+, K+-ATPase activity was higher in gills of T exposed to 11 ppt salinity as well as the whole body content of Na+. Increased ATP content was observed in gills of both NT and T exposed to 11 ppt salinity, being statistically higher in T than NT. Taking altogether, these findings support the hypothesis that GH-transgenesis increases Na+ import capacity and energetic demand, promoting an unfavorable osmotic and energetic physiological status and making this transgenic fish intolerant of hyperosmotic environments. 相似文献