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41.
Willis SC Nunes MS Montaña CG Farias IP Lovejoy NR 《Molecular phylogenetics and evolution》2007,44(1):291-307
To investigate forces influencing diversification in Neotropical fishes, the phylogenetic relationships among species and populations of the cichlid genus Cichla were examined. Mitochondrial DNA was sequenced for 454 individuals of the 5 nominal Cichla species and several putative undescribed species. Phylogenetic analyses support the distinction of two major clades of Cichla. Clade A includes C. temensis and two undescribed species from the lower Amazonas and Xingu Rivers. Clade B includes C. orinocensis, C. monoculus, C. ocellaris. C, intermedia, and an undescribed species from the upper Madeira River. Species boundaries were relatively well-circumscribed for clade B, while incomplete lineage sorting was inferred for clade A. Three probable instances of introgression were observed, including a regional population of C. orinocensis from the Negro River that shows a history of introgression. Biogeographic patterns from Cichla are partially congruent with those seen in several other Neotropical fish clades, and the diversification of Cichla species is inferred to result from both vicariance and sympatric divergence. 相似文献
42.
Rolim MF Riger CJ Eleutherio EC Colão Cda F Pereira GC Schanaider A 《Redox report : communications in free radical research》2007,12(6):267-274
This experimental study aimed to evaluate colon healing after portal ischemia followed by reperfusion. Seventy male Wistar rats randomly distributed in four groups were used: Group 1, colonic anastomosis (n = 20); Group 2, portal ischemia-reperfusion (n = 20); Group 3, colonic anastomosis and portal ischemia-reperfusion (n = 20); and Group 4, control (n = 10). In the postoperative period, these rats were re-allocated into subgroups and lipid peroxidation and protein oxidation plasma levels were evaluated on days 1 and 5 by thiobarbituric acid reactive substances (TBARS) and slot-blotting assays, respectively. A segment of the right colon was also removed for collagen analysis. Both malondialdehyde (MDA) and protein carbonyl levels (oxidative markers of lipids and proteins) presented a significant increase after reperfusion in Group 3 on days 1 (P < 0.002) and 5 (P < 0.0001). In this same group, an extensive inflammatory process showing decreased fibroplasia was observed, with deficiency in collagen deposition on both sides of the anastomosis edges. Taken together, these results indicate that portal congestion followed by reperfusion induces an oxidative stress, which impaired the mechanism of colon anastomotic healing. 相似文献
43.
dos Santos SG Diniz CG da Silva VL Souza NC de Lima FL Bomfim MR de Carvalho MA Farias LM 《Journal of applied microbiology》2007,103(4):882-891
AIM: This study focuses on investigating the molecular and physiological characteristics of Prevotella intermedia after molecular oxygen exposure (MOE) and the effect on drug susceptibility patterns. METHODS AND RESULTS: Samples of P. intermedia were used as parent strains: ATCC25611 and four clinical isolates. Strains adapted to oxidative stress by MOS were obtained by the enrichment technique. Drug susceptibility was evaluated by minimal inhibitory concentrations (MIC) using agar dilution. Arbitrarily primed-polymerase chain reaction (AP-PCR) was used to evaluate the genetic diversity of all strains and physiological analyses were made by sodiumdodecylsulfate-polyacrylamide gel electrophoresis and two-dimensional electrophoresis of crude, cell-free extracts. The genetic profile showed that lineages with altered MIC values were selected after MOE. Overall, we found significant decrease in drug susceptibility for the aero-strains against all tested antimicrobials (amoxicillin, amoxicillin+clavulanic acid, clindamycin, chloramphenicol, ertapenen and metronidazole). We also observed markedly different protein expression patterns between the parent and selected aero-strains. CONCLUSIONS: MOE induces changes in the genetic profile and protein expression patterns of P. intermedia that may also be linked to its drug resistance mechanisms. SIGNIFICANCE AND IMPACT OF THE STUDY: The effects of MOE on anaerobic bacterial physiology and behaviour may influence antimicrobial susceptibility patterns with potential consequences to antimicrobial chemotherapy. 相似文献
44.
Previously we characterized an acetyl-esterase from Escherichia coli, formally Aes, from a thermodynamic point of view in comparative studies with thermophilic homologs. Since the enzyme appeared unusually resistant to the thermal denaturation we analysed the kinetic behaviour with respect to the temperature. The enzyme displays a surprising optimal temperature at 65 degrees C, showing a specific activity of 250 U/mg using pNP-butanoate as substrate, but a low kinetic stability at the same temperature (t(1/2) of inactivation=5 min). By a random mutagenesis approach we searched for mutated versions of Aes with increased thermostability. We found the mutant T74A, which shows the same specific activity of wild type but a t(1/2) of inactivation of 30 min at 65 degrees C. 相似文献
45.
Daniel Martins Bruno Menezes de Oliveira Alessandro dos Santos Farias Ricardo Shiniti Oka Horiuchi Cleyton Crepaldi Domingues Eneida de Paula Sérgio Marangoni Wagner Farid Gattaz Emmanuel Dias-Neto José Camillo Novello 《Briefings in Functional Genomics and Prot》2007,6(1):70-75
Protein extraction is the most important step to reveal a proteome by Two-Dimensional Gel Electrophoresis. Usually, the urea/thiourea based standard protein extraction buffer (SB) is combined with detergents with the aim of achieving better resolution and solubilization of different classes of proteins. In order to produce better gels and achieve the greatest spot resolution of Human Brain Proteins, comparisons using 2-DE of extracted proteins from Human Brain Frontal Cortex with SB constituents (7M Urea, 2M Thiourea and 100mM DTT) were made, using different detergent compositions in the buffer. SB preparations in combination with CHAPS and ASB-14 as well as with ASB-16 (reported for the first time in 2-DE experiments) have been tested. Our results confirm that the most efficient solubilizing solution for 2-DE analysis of cytosolic and membrane Human Brain Proteins is SB combined with 4% CHAPS and 2% ASB-14. 相似文献
46.
Farias RC Madeira-da-Silva MC Pereira-Peixoto MH Martins CF 《Neotropical Entomology》2007,36(6):863-867
Euglossina bees form a group with about 200 species known, widespread in Neotropical Region. Males collect aromatic compounds on flowers and by using synthesized analogs it is possible to accomplish faunistic inventories and study several ecological aspects of these bees. In this work we studied the activity hours and the preference of aromatic compounds by Euglossina males in forest and dunes at Environmental Protection Area of the Mamanguape River Bar, Rio Tinto, Paraíba State, between August 2002 and July 2004. Six artificial compounds were used as attractive: benzyl acetate, ionone beta, skatole, eucalyptol, eugenol and vanillin. Nine species were sampled, being two of them exclusive of the forest. Euglossa cordata (L.) and Eulaema nigrita Lepeletier were the most abundant species as in the forest as on dunes. Males were more active between 8:00 a.m. and 10:00 a.m. in both areas, with no variation throughout the year. Eucalyptol and eugenol attracted most number of species. E. cordata demonstrated preference by ionone beta and eucalyptol and E. nigrita by skatole and eucalyptol. 相似文献
47.
Piccinini Alexandre Oliveira Mariana Pacheco Silva Mariella Reinol Bett Gabriela Souza Becker Isabel Borges Mendes Talita Farias Salla Daniéle Hendler Silva Larissa Espindola Vilela Thais Ceresér Moraes Fernanda Mendes Moterle Diego Damiani Adriani Paganini Dagostin Lígia Salvan Tietbohl Lariani Tamires Bittencourt João Vitor Silvano Biehl Erica Denicol Tais Luise Bonfante Sandra Regina Andrade Vanessa Moraes Silveira Paulo Cesar Lock Prophiro Josiane Somariva Ferreira Gabriela Kozuchovski Petronilho Fabricia Kanis Luiz Alberto Rezin Gislaine Tezza 《Neurochemical research》2022,47(7):1888-1903
Neurochemical Research - This study aimed to evaluate the effect of Cynara cardunculus leaf ethanol extract on inflammatory and oxidative stress parameters in the hypothalamus, prefrontal cortex,... 相似文献
48.
Fernandes Jackellynne Fernanda Farias Freitas Jailza de Araújo Sandra Alves de Santana Thiago Campos Lobato Rafael Santos Figueiredo Marina Bezerra 《Environmental Biology of Fishes》2022,105(8):1033-1050
Environmental Biology of Fishes - To clarify the reproductive activity of lane snapper, Lutjanus synagris, a total of 359 specimens of lane snapper were collected in partnership with an artisanal... 相似文献
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