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991.
Carolina Mascayano Gabriel Núñez Waldo Acevedo Marcos Caroli Rezende 《Journal of molecular modeling》2010,16(5):1039-1045
The lipoxygenases (LOX) are a family of non-heme iron-containing dioxygenases which catalyze the stereospecific insertion
of molecular oxygen into arachidonic acid, leading to hydroxy derivatives as end products. In this work, we docked arachidonic
acid and two of its competitive inhibitors, flavonoids baicalein and quercetin, into the binding pockets of human 12- and
15-lipoxygenase. Steered molecular dynamics (SMD) simulations were employed to study the unbinding processes of the substrate
and inhibitors from the two isoforms. 相似文献
992.
993.
Differential expression analysis of Escherichia coli proteins using a novel software for relative quantitation of LC-MS/MS data 总被引:2,自引:0,他引:2
Johansson C Samskog J Sundström L Wadensten H Björkesten L Flensburg J 《Proteomics》2006,6(16):4475-4485
The study of changes in protein levels between samples derived from cells representing different biological conditions is a key to the understanding of cellular function. There are two main methods available that allow both for global scanning for significantly varying proteins and targeted profiling of proteins of interest. One method is based on 2-D gel electrophoresis and image analysis of labelled proteins. The other method is based on LC-MS/MS analysis of either unlabelled peptides or peptides derived from isotopically labelled proteins or peptides. In this study, the non-labelling approach was used involving a new software, DeCyder MS Differential Analysis Software (DeCyder MS) intended for automated detection and relative quantitation of unlabelled peptides in LC-MS/MS data.Total protein extracts of E. coli strains expressing varying levels of dihydrofolate reductase and integron integrase were digested with trypsin and analyzed using a nanoscale liquid chromatography system, Ettan MDLC, online connected to an LTQTM linear ion-trap mass spectrometer fitted with a nanospray interface. Acquired MS data were subjected to DeCyder MS analysis where 2-D representations of the peptide patterns from individual LC-MS/MS analyses were matched and compared.This approach to unlabelled quantitative analysis of the E. coli proteome resulted in relative protein abundances that were in good agreement with results obtained from traditional methods for measuring protein levels. 相似文献
994.
We performed random amplification of polymorphic DNA (RAPD) analysis on five strains of Alexandrium tamarense and nine strains of Alexandrium minutum. Arbitrary 10-mer oligonucleotides were used as primers for the PCR. Electrophoresis on denaturing acrylamide gels improved RAPD reproducibility and increased the band number. Eight of the 20 primers assayed gave reproducible results and the band profiles generated by them were used for constructing a similarity matrix. Analyses were performed independently for the strains of each species and jointly for all the strains of both species. Results for A. tamarense showed the highest similarity for two distinct clones isolated from the same water sample in the Baltic Sea during a bloom (KAC01 and KAC02). The highest similarity among A. minutum clones was found for three strains (AL1V, AL2V and AL3V) isolated in the Ria de Vigo in NW Spain. The results show a high genetic diversity within a single species. We have shown the potential of the RAPD technique to discriminate between two conspecific strains, as well as for establishing similarities that are related to the biogeographic origin of the strains. 相似文献
995.
Asn- and Asp-mediated interactions between transmembrane helices during translocon-mediated membrane protein assembly 下载免费PDF全文
Inter-helix hydrogen bonding involving asparagine (Asn, N), glutamine (Gln, Q), aspartic acid (Asp, D) or glutamic acid (Glu, E) can drive efficient di- or trimerization of transmembrane helices in detergent micelles and lipid bilayers. Likewise, Asn-Asn and Asp-Asp pairs can promote the formation of helical hairpins during translocon-mediated membrane protein assembly in the endoplasmic reticulum. By in vitro translation of model integral membrane protein constructs in the presence of rough microsomes, we show that Asn- or Asp-mediated interactions with a neighbouring transmembrane helix can enhance the membrane insertion efficiency of a marginally hydrophobic transmembrane segment. Our observations suggest that inter-helix hydrogen bonds can form during Sec61 translocon-assisted insertion and thus could be important for membrane protein assembly. 相似文献
996.
Background
The annotations of Affymetrix DNA microarray probe sets with Gene Ontology terms are carefully selected for correctness. This results in very accurate but incomplete annotations which is not always desirable for microarray experiment evaluation. 相似文献997.
Oliveira Tatiane R Fernandez-Becerra Carmen Jimenez Maria Carolina S Del Portillo Hernando A Soares Irene S 《Malaria journal》2006,5(1):1-10
Background
Chloroquine (CQ) or sulfadoxine-pyrimethamine (SP) monotherapy for Plasmodium falciparum often leads to therapeutic failure in Indonesia. Combining CQ with other drugs, like SP, may provide an affordable, available and effective option where artemisinin-combined therapies (ACT) are not licensed or are unavailable.Methods
This study compared CQ (n = 29 subjects) versus CQ + SP (with or without primaquine; n = 88) for clinical and parasitological cure of uncomplicated falciparum malaria in the Menoreh Hills region of southern Central Java, Indonesia. Gametocyte clearance rates were measured with (n = 56 subjects) and without (n = 61) a single 45 mg dose of primaquine (PQ).Results
After 28 days, 58% of subjects receiving CQ had cleared parasitaemia and remained aparasitaemic, compared to 94% receiving CQ combined with SP (p < 0.001). Msp-2 genotyping permitted reinfection-adjusted cure rates for CQ and CQ combined with SP, 70% and 99%, respectively (p = 0.0006).Conclusion
Primaquine exerted no apparent affect on cure of asexual stage parasitaemia, but clearly accelerated clearance of gametocytes. CQ combined with SP was safe and well-tolerated with superior efficacy over CQ for P. falciparum parasitaemia in this study. 相似文献998.
999.
Abud AP Cesar B Cavazzani LF de Oliveira CC Gabardo J Buchi Dde F 《Cell biology international》2006,30(10):808-816
Canova is a Brazilian complex homeopathic medication produced from Aconitum, Thuya, Bryonia, Lachesis and Arsenicum. Previous studies demonstrated that Canova induces up-regulation in numbers of leukocytes. The bone marrow microenvironment is composed of growth factors, stromal cells, extracellular matrix, and progenitor cells that differentiate into mature blood cells. As it is the major site of blood cell formation, we studied in vitro Canova effects on bone marrow cells of mice. Swiss mouse femurs were dissected, cleaned, and the marrow was flushed. The cells were plated, treated or not, incubated for different times and processed for light, scanning electron, and confocal microscopy, and also flow cytometry. The treatment did not modify the expression of the analyzed surface markers or cytokine production. All microscopy techniques showed that a monocytic lineage (CD11b(+)) and stromal cells (adherent cells) were activated by treatment. Canova also increased cell clusters over adherent cells, suggesting proliferation areas. 相似文献
1000.
Soto-Otero R Sanmartín-Suárez C Sánchez-Iglesias S Hermida-Ameijeiras A Sánchez-Sellero I Méndez-Alvarez E 《Journal of biochemical and molecular toxicology》2006,20(5):209-220
Tetrahydropapaveroline (THP) is a compound derived from dopamine monoamine oxidase-mediated metabolism, particularly present in the brain of parkinsonian patients receiving L-dopa therapy, and is capable of causing dopaminergic neurodegeneration. The aim of this work was to evaluate the potential of THP to cause oxidative stress on mitochondrial preparations and to gain insight into the molecular mechanisms responsible for its neurotoxicity. Our data show that THP autoxidation occurs with a continuous generation of hydroxyl radicals (*OH) and without the involvement of the Fenton reaction. The presence of ascorbate enhances this process by establishing a redox cycle, which regenerates THP from its quinolic forms. It has been shown that the production of *OH is not affected by the presence of either ferrous or ferric iron. Although THP does not affect lipid peroxidation, it is capable of reducing the high levels of thiobarbituric acid-reactive substances obtained in the presence of ascorbate and/or iron. However, THP autoxidation in the presence of ascorbate causes both an increase in protein carbonyl content and a reduction in protein-free thiol content. THP also increases protein carbonyl content when the autoxidation occurs in the presence of iron. The remarkable role played by ascorbate in the production of oxidative stress by THP autoxidation is of particular interest. 相似文献