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901.
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903.
Costa BB Corrêa R De Souza MM Pretto JB Ardenghi JV De Campos-Buzzi F Cechinel Filho V 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(3-4):201-206
This paper describes the antinociceptive effects of tetrahydrophthalimides and related compounds in mice. Twenty compounds were obtained by the reaction of cis-1,2,3,6-tetrahydrophthalic anhydride with appropriate amines, dehydration, and addition to the imidic double bond. They were analyzed in the writhing test at 10 mg/kg given intraperitoneally. The most active compound 2-benzyl-5-morpholin-4-yl-hexahydroisoindole-1,3-dione (19) was studied on formalin, capsaicin, glutamate and hot plate models. The antinociceptive activity demonstrated by some studied compounds is promising, and some of them were more active than acetylsalicylic acid and paracetamol used as reference drugs in writhing tests in mice. Compound 19 was about 5-fold more potent than the reference drugs, being also effective by oral route and against the inflammatory response in the formalin test. The results suggest that compound 19 could be used as a model to obtain new and more potent antinociceptive agents. It exhibits an interesting antinociceptive profile, and does not interact with opioid systems. 相似文献
904.
do Nascimento AM Costa FC Thiemann OH de Oliveira DC 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(5-6):353-356
The dichloromethane extract of Calea uniflora afforded a mixture of two novel chromanones, uniflorol-A (1) and uniflorol-B (2), and one known chromanone, 2,2-dimethyl-6-(1-hydroxyethyl)-chroman-4-one (3). The structures of these compounds were determined by spectroscopic methods. Biological activity of the compounds against Leishmania major promastigotes was evaluated. Mixture of the novel chromanones 1 and 2 showed significant growth inhibition of the parasite in the micrograms per milliliter range. 相似文献
905.
Andrade PM Ribeiro BG Bozza MT Costa Rosa LF Tavares do Carmo MG 《Prostaglandins, leukotrienes, and essential fatty acids》2007,77(3-4):139-145
The effect of fish-oil supplementation (FO-S) on the immune responses of elite swimmers was investigated. In a randomized placebo-controlled trial, swimmers received either fish-oil capsules (n=10) containing long chain polyunsaturated fatty acids (FA) of n-3 (LCPUFA n-3) or placebo capsules (n=10), both for 6 weeks. Plasma FA, immunological markers, insulin and cortisol were evaluated. The FO-S resulted in an increase in LCPUFA n-3 and a decrease in arachidonic n-6 FA in plasma and a reduction in the production of interferon-gamma by cultured cells. A reduction in the production of tumor necrosis factor-alpha was observed in both groups. An increase in interleukin-2 production and no significant difference in interleukin-4 were also observed. FO-S was able to attenuate the exercise-induced increases in prostaglandin E2. Circulating concentrations of insulin did not change, while cortisol and glucose showed increase after the study period. These results suggest that FO-S influence exercise-associated immune responses in competitive swimmers. 相似文献
906.
The Hsp70 chaperone machines of Escherichia coli: a paradigm for the repartition of chaperone functions 总被引:1,自引:1,他引:0
Molecular chaperones are highly conserved in all free-living organisms. There are many types of chaperones, and most are conveniently grouped into families. Genome sequencing has revealed that many organisms contain multiple members of both the DnaK (Hsp70) family and their partner J-domain protein (JDP) cochaperone, belonging to the DnaJ (Hsp40) family. Escherichia coli K-12 encodes three Hsp70 genes and six JDP genes. The coexistence of these chaperones in the same cytosol suggests that certain chaperone-cochaperone interactions are permitted, and that chaperone tasks and their regulation have become specialized over the course of evolution. Extensive genetic and biochemical analyses have greatly expanded knowledge of chaperone tasking in this organism. In particular, recent advances in structure determination have led to significant insights of the underlying complexities and functional elegance of the Hsp70 chaperone machine. 相似文献
907.
Costa R Gomes NC Krögerrecklenfort E Opelt K Berg G Smalla K 《Environmental microbiology》2007,9(9):2260-2273
The Pseudomonas community structure and antagonistic potential in the rhizospheres of strawberry and oilseed rape (host plants of the fungal phytopathogen Verticillium dahliae) were assessed. The use of a new PCR-DGGE system, designed to target Pseudomonas-specific gacA gene fragments in environmental DNA, circumvented common biases of 16S rRNA gene-based DGGE analyses and proved to be a reliable tool to unravel the diversity of uncultured Pseudomonas in bulk and rhizosphere soils. Pseudomonas-specific gacA fingerprints of total-community (TC) rhizosphere DNA were surprisingly diverse, plant-specific and differed markedly from those of the corresponding bulk soils. By combining multiple culture-dependent and independent surveys, a group of Pseudomonas isolates antagonistic towards V. dahliae was shown to be genotypically conserved, to carry the phlD biosynthetic locus (involved in the biosynthesis of 2,4-diacetylphloroglucinol - 2,4-DAPG), and to correspond to a dominant and highly frequent Pseudomonas population in the rhizosphere of field-grown strawberries planted at three sites in Germany which have different land use histories. This population belongs to the Pseudomonas fluorescens phylogenetic lineage and showed closest relatedness to P. fluorescens strain F113 (97% gacA gene sequence identity in 492-bp sequences), a biocontrol agent and 2,4-DAPG producer. Partial gacA gene sequences derived from isolates, clones of the strawberry rhizosphere and DGGE bands retrieved in this study represent previously undescribed Pseudomonas gacA gene clusters as revealed by phylogenetic analysis. 相似文献
908.
Angel R Barchuk Alexandre S Cristino Robert Kucharski Luciano F Costa Zilá LP Simões Ryszard Maleszka 《BMC developmental biology》2007,7(1):70
Background
In honeybees, differential feeding of female larvae promotes the occurrence of two different phenotypes, a queen and a worker, from identical genotypes, through incremental alterations, which affect general growth, and character state alterations that result in the presence or absence of specific structures. Although previous studies revealed a link between incremental alterations and differential expression of physiometabolic genes, the molecular changes accompanying character state alterations remain unknown. 相似文献909.
The recent availability of genome-scale genotyping data has led to the identification of regions of the human genome that seem to have been targeted by selection. These findings have increased our understanding of the evolutionary forces that affect the human genome, have augmented our knowledge of gene function and promise to increase our understanding of the genetic basis of disease. However, inferences of selection are challenged by several confounding factors, especially the complex demographic history of human populations, and concordance between studies is variable. Although such studies will always be associated with some uncertainty, steps can be taken to minimize the effects of confounding factors and improve our interpretation of their findings. 相似文献
910.
Juliana S Bernardes Alberto MR Dávila Vítor S Costa Gerson Zaverucha 《BMC bioinformatics》2007,8(1):435