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101.
Felipe de Oliveira Fernandes Sérgio Ricardo de Oliveira Vitor Klein Marcella Araújo do Amaral Carneiro Pio Colepicolo Eliane Marinho-Soriano 《Journal of applied phycology》2017,29(2):695-705
The genus Gracilaria is one of the most important sources of agar in the world. In Brazil, Gracilaria birdiae is the main commercially exploited species; however, overexploitation has contributed to the depletion of natural beds. In order to obtain more information so as to consolidate G. birdiae cultivation, studies under laboratory (indoor and outdoor) and field (sea and shrimp pond) conditions were conducted to evaluate the effects of fertilizer pulses on biomass and relative growth rate (RGR) of this species. The following nutrient sources used were (T1) shrimp-pond effluent, (T2) fertilizer for aquarium plants (Mbreda), and (T3) fertilizer extract of Ascophyllum nodosum (Acadian). Significant differences for growth were recorded over time for all treatments in both outdoor and field conditions (p < 0.001). The highest RGRs were recorded for treatments that used pulses of commercial fertilizers (T2 and T3) and the lowest for treatment using shrimp-pond effluent pulses (T1). The analysis of the nutrient content in tissue also showed a relationship between growth and nitrogen and phosphorus accumulation in the algal tissues. The N/P ratio indicated a significant effect on the growth of G. birdiae and the highest RGRs were registered for seedlings with a N/P ratio ≥16 (T2 and T3). In conclusion, the best results were recorded for the Mbreda and Acadian commercial fertilizers. However, although no significant differences were detected between growth and the two fertilizers (T2 and T3), the seedlings cultivated under Acadian pulses showed a better performance against environmental stress caused by reduced salinity. 相似文献
102.
103.
dos Santos Fernanda Marcelia Pflüger Pricila Fernandes Lazzarotto Leticia Uczay Mariana de Aguida Wesley Roberto da Silva Lisiane Santos Boaretto Fernanda Brião Menezes de Sousa Jayne Torres Picada Jaqueline Nascimento da Silva Torres Iraci Lucena Pereira Patrícia 《Neurochemical research》2021,46(8):2066-2078
Neurochemical Research - Gamma-decanolactone (GD) has been shown to reduce epileptic behavior in different models, inflammatory decreasing, oxidative stress, and genotoxic parameters. This study... 相似文献
104.
105.
Tobias Schwarzmüller Biao Ma Ekkehard Hiller Fabian Istel Michael Tscherner Sascha Brunke Lauren Ames Arnaud Firon Brian Green Vitor Cabral Marina Marcet-Houben Ilse D. Jacobsen Jessica Quintin Katja Seider Ingrid Frohner Walter Glaser Helmut Jungwirth Sophie Bachellier-Bassi Murielle Chauvel Ute Zeidler Dominique Ferrandon Toni Gabaldón Bernhard Hube Christophe d'Enfert Steffen Rupp Brendan Cormack Ken Haynes Karl Kuchler 《PLoS pathogens》2014,10(6)
The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. 相似文献
106.
Graziele Fonseca de Sousa Maira de Assis Lima Débora Fernandes Custodio Vanessa Morais Freitas Gisele Monteiro 《PloS one》2015,10(12)
The use of carboplatin in cancer chemotherapy is limited by the emergence of drug resistance. To understand the molecular basis for this resistance, a chemogenomic screen was performed in 53 yeast mutants that had previously presented strong sensitivity to this widely used anticancer agent. Thirty-four mutants were responsive to carboplatin, and from these, 21 genes were selected for further studies because they have human homologues. Sixty percent of these yeast genes possessed human homologues which encoded proteins that interact with cullin scaffolds of ubiquitin ligases, or whose mRNA are under the regulation of Human antigen R (HuR) protein. Both HuR and cullin proteins are regulated through NEDDylation post-translational modification, and so our results indicate that inhibition of this process should sensitise resistant tumour cells to carboplatin. We showed that treatment of a tumour cell line with MLN4924, a NEDDylation inhibitor, overcame the resistance to carboplatin. Our data suggest that inhibition of NEDDylation may be a useful strategy to resensitise tumour cells in patients that have acquired carboplatin resistance. 相似文献
107.
Protection against toxoplasmosis in mice immunized with different antigens of Toxoplasma gondii incorporated into liposomes. 总被引:5,自引:0,他引:5
Different toxoplasma antigens were entrapped within liposomes and evaluated, in this form, for their ability to protect Swiss mice against toxoplasma infection: soluble tachyzoite antigen (L/TAg), tissue cyst (L/CAg), tachyzoite plus tissue cyst (L/TCAg) or purified antigen of tachyzoite (L/pTAg). The protein used in L/pTAg was purified from tachyzoites using a stage-specific monoclonal antibody which reacted at a molecular weight of 32 kD in SDS PAGE and silver stain using reduced condition. To compare the immuno-adjuvant action of liposomes and of Freund's Complete Adjuvant (FCA), another group of mice was immunized with soluble tachyzoite antigen (STAg) emulsified in FCA (FCA/TAg). Control groups were inoculated with (STAg) alone, phosphate-buffered saline (PBS), FCA with PBS (FCA/PBS) and empty liposomes (L/PBS). Mice were inoculated subcutaneously with these antigens six, four and two weeks before a challenge with 80 tissue cysts of the P strain of Toxoplasma gondii orally. All mice immunized with or without adjuvant showed a humoral response, as measured by Elisa. However, no correlation was found between antibody titer and protection against the challenge. All mice immunized with L/pTAg or L/TCAg survived (100), whereas 80% and 90% of mice from groups which received respectively PBS or FCA/PBS and L/PBS died. All mice immunized with antigens entrapped within liposomes (L/TAg, L/CAg, L/TCAg and L/pTAg) showed low numbers of intracerebral cysts. 相似文献
108.
Sugarcane (Saccharum X officinarum): A Reference Study for the Regulation of Genetically Modified Cultivars in Brazil 总被引:1,自引:0,他引:1
Cheavegatti-Gianotto A de Abreu HM Arruda P Bespalhok Filho JC Burnquist WL Creste S di Ciero L Ferro JA de Oliveira Figueira AV de Sousa Filgueiras T Grossi-de-Sá MD Guzzo EC Hoffmann HP de Andrade Landell MG Macedo N Matsuoka S de Castro Reinach F Romano E da Silva WJ de Castro Silva Filho M César Ulian E 《Tropical plant biology》2011,4(1):62-89
Global interest in sugarcane has increased significantly in recent years due to its economic impact on sustainable energy production. Sugarcane breeding and better agronomic practices have contributed to a huge increase in sugarcane yield in the last 30?years. Additional increases in sugarcane yield are expected to result from the use of biotechnology tools in the near future. Genetically modified (GM) sugarcane that incorporates genes to increase resistance to biotic and abiotic stresses could play a major role in achieving this goal. However, to bring GM sugarcane to the market, it is necessary to follow a regulatory process that will evaluate the environmental and health impacts of this crop. The regulatory review process is usually accomplished through a comparison of the biology and composition of the GM cultivar and a non-GM counterpart. This review intends to provide information on non-GM sugarcane biology, genetics, breeding, agronomic management, processing, products and byproducts, as well as the current technologies used to develop GM sugarcane, with the aim of assisting regulators in the decision-making process regarding the commercial release of GM sugarcane cultivars. 相似文献
109.
Ronaldo Z. Mendonça Katia N. Greco Alvaro P. B. Sousa Roberto H. P. Moraes Renato M. Astray Carlos A. Pereira 《Cytotechnology》2008,57(1):83-91
Gene expression in animal cells allows large scale production of proteins used for either structure and function studies or
therapeutic purposes. Maximizing recombinant protein production is necessary to optimize cell growth and protein expression.
Some studies have demonstrated the presence of pharmacologically active substances in insect hemolymph. In this work, we have
identified and purified a protein from Lonomia obliqua hemolymph able to increase the production of the rabies virus glycoprotein, expressed in Drosophila melanogaster S2 cells, by about 59%. 相似文献
110.