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141.
N. Maira T. M. Torres A. L. de Oliveira S. R. B. de Medeiros L. F. Agnez‐Lima J. P. M. S. Lima K. C. Scortecci 《Plant biology (Stuttgart, Germany)》2014,16(3):622-631
Unlike bacteria and mammals, plant DNA repair pathways are not well characterised, especially in monocots. The understanding of these processes in the plant cell is of major importance, since they may be directly involved in plant acclimation and adaptation to stressful environments. Hence, two sugarcane ESTs were identified as homologues of AP endonuclease from the base‐excision repair pathway: ScARP1 and ScARP3. In order to understand their probable function and evolutionary origin, structural and phylogenetic studies were performed using bioinformatics approaches. The two predicted proteins present a considerable amino acid sequence similarity, and molecular modelling procedures indicate that both are functional, since the main structural motifs remain conserved. However, inspection of the sort signal regions on the full‐length cDNAs indicated that these proteins have a distinct organelle target. Furthermore, variances in their promoter cis‐element motifs were also found. Although the mRNA expression pattern was similar, there were significant differences in their expression levels. Taken together, these data raise the hypothesis that the ScARP is an example of a probable gene duplication event that occurred before monocotyledon/dicotyledon segregation, followed by a sub‐functionalisation event in the Poaceae, leading to new intracellular targeting and different expression levels. 相似文献
142.
Carolina P. B. Gracitelli Andrew J. Tatham Linda M. Zangwill Robert N. Weinreb Ting Liu Felipe A. Medeiros 《PloS one》2014,9(8)
Purpose
To evaluate whether optic disc hemorrhages are associated with faster rates of estimated retinal ganglion cell (RGC) loss in glaucoma.Methods
A longitudinal observational cohort study of 222 eyes of 122 patients with glaucoma recruited from the Diagnostic Innovations Glaucoma Study (DIGS) followed for an average of 3.74±0.85 years. All subjects had optical coherence tomography and standard automated perimetry during follow up. Optic disc hemorrhages were detected by masked evaluation of stereophotographs. Rates of change in estimated numbers of RGCs were determined using a previously described method. A random coefficients model was used to investigate the relationship between disc hemorrhages and rates of change in estimated RGC counts over time.Results
19 eyes of 18 subjects had at least one disc hemorrhage during follow up. At baseline, average estimated RGC counts in eyes with and without disc hemorrhages were 677,994 cells and 682,021 cells, respectively (P = 0.929). Eyes with optic disc hemorrhages during follow-up had significantly faster rates of estimated RGC loss than eyes without disc hemorrhages (22,233 cells/year versus 10,704 cells/year, P = 0.020). The effect of disc hemorrhages on the rates of estimated RGC loss remained significant after adjusting for confounding variables.Conclusion
Eyes with disc hemorrhages showed faster rates of RGC loss compared to eyes without disc hemorrhages. These results provide further evidence that disc hemorrhages should be considered as an indicator of increased risk for faster neural loss in glaucoma. 相似文献143.
Haydée A. Cunha Bruna V. Medeiros Lupércio A. Barbosa Marta J. Cremer Juliana Marigo José Lailson-Brito Alexandre F. Azevedo Antonio M. Solé-Cava 《PloS one》2014,9(1)
Franciscanas are the most endangered dolphins in the Southwestern Atlantic. Due to their coastal and estuarine habits, franciscanas suffer from extensive fisheries bycatch, as well as from habitat loss and degradation. Four Franciscana Management Areas (FMA), proposed based on biology, demography, morphology and genetic data, were incorporated into management planning and in the delineation of research efforts. We re-evaluated that proposal through the analysis of control region sequences from franciscanas throughout their distribution range (N = 162), including novel sequences from the northern limit of the species and two other previously unsampled localities in Brazil. A deep evolutionary break was observed between franciscanas from the northern and southern portions of the species distribution, indicating that they must be managed as two Evolutionarily Significant Units (ESU). Furthermore, additional FMAs should be recognised to accommodate the genetic differentiation found in each ESU. These results have immediate consequences for the conservation and management of this endangered species. 相似文献
144.
Alexandre Medeiros do Carmo Fabiana Maria Santos Carmen Lucia Ortiz-Agostinho Iêda Nishitokukado Cintia S. Frota Flavia Ubeda Gomes André Zonetti de Arruda Leite Claudio Sérgio Pannuti Lucy Santos Vilas Boas Magaly Gemio Teixeira Aytan Miranda Sipahi 《PloS one》2014,9(11)
Background
Cytomegalovirus is highly prevalent virus and usually occurs in immunocompromised patients. The pathophysiology and treatment of inflammatory bowel disease often induce a state of immunosuppression. Because this, there are still doubts and controversies about the relationship between inflammatory bowel disease and cytomegalovirus.Aim
Evaluate the frequency of cytomegalovirus in patients with inflammatory bowel disease and identify correlations.Methods
Patients with inflammatory bowel disease underwent an interview, review of records and collection of blood and fecal samples. The search for cytomegalovirus was performed by IgG and IgM blood serology, by real-time PCR in the blood and by qualitative PCR in feces. Results were correlated with red blood cell levels, C-reactive protein levels, erythrocyte sedimentation rates and fecal calprotectin levels for each patient.Results
Among the 400 eligible patients, 249 had Crohn''s disease, and 151 had ulcerative colitis. In the group of Crohn''s disease, 67 of the patients had moderate or severe disease, but 126 patients presented with active disease, based on the evaluation of the fecal calprotectin. In patients with ulcerative colitis, only 21 patients had moderate disease, but 76 patients presented with active disease, based on the evaluation of the fecal calprotectin. A large majority of patients had positive CMV IgG. Overall, 10 patients had positive CMV IgM, and 9 patients had a positive qualitative detection of CMV DNA by PCR in the feces. All 400 patients returned negative results after the quantitative detection of CMV DNA in blood by real-time PCR. Analyzing the 19 patients with active infections, we only found that such an association occurred with the use of combined therapy (anti-TNF-alpha + azathioprine)Conclusion
The findings show that latent cytomegalovirus infections are frequent and active cytomegalovirus infection is rare. We did not find any association between an active infection of CMV and inflammatory bowel disease activity. 相似文献145.
Fernanda Barbisan Jéssica de Rosso Motta Alexis Trott Ver?nica Azzolin Eduardo Bortoluzzi Dornelles Matheus Marcon Thaís Doeler Algarve Marta Maria Medeiros Frescura Duarte Clarice Pinheiro Mostardeiro Taís Cristina Unfer Karen Lilian Schott Ivana Beatrice Manica da Cruz 《PloS one》2014,9(10)
Methotrexate (MTX) is a folic acid antagonist used in high doses as an anti-cancer treatment and in low doses for the treatment of some autoimmune diseases. MTX use has been linked to oxidative imbalance, which may cause multi-organ toxicities that can be attenuated by antioxidant supplementation. Despite the oxidative effect of MTX, the influence of antioxidant gene polymorphisms on MTX toxicity is not well studied. Therefore, we analyzed here whether a genetic imbalance of the manganese-dependent superoxide dismutase (SOD2) gene could have some impact on the MTX cytotoxic response. An in vitro study using human peripheral blood mononuclear cells (PBMCs) obtained from carriers with different Ala16Val-SOD2 genotypes (AA, VV and AV) was carried out, and the effect on cell viability and proliferation was analyzed, as well as the effect on oxidative, inflammatory and apoptotic markers. AA-PBMCs that present higher SOD2 efficiencies were more resistance to high MTX doses (10 and 100 µM) than were the VV and AV genotypes. Both lipoperoxidation and ROS levels increased significantly in PBMCs exposed to MTX independent of Ala16Val-SOD2 genotypes, whereas increased protein carbonylation was observed only in PBMCs from V allele carriers. The AA-PBMCs exposed to MTX showed decreasing SOD2 activity, but a concomitant up regulation of the SOD2 gene was observed. A significant increase in glutathione peroxidase (GPX) levels was observed in all PBMCs exposed to MTX. However, this effect was more intense in AA-PBMCs. Caspase-8 and -3 levels were increased in cells exposed to MTX, but the modulation of these genes, as well as that of the Bax and Bcl-2 genes involved in the apoptosis pathway, presented a modulation that was dependent on the SOD2 genotype. MTX at a concentration of 10 µM also increased inflammatory cytokines (IL-1β, IL-6, TNFα and Igγ) and decreased the level of IL-10 anti-inflammatory cytokine, independent of SOD2 genetic background. The results suggest that potential pharmacogenetic effect on the cytotoxic response to MTX due differential redox status of cells carriers different SOD2 genotypes. 相似文献
146.
Marcio R. T. Nunes Gustavo Palacios Nuno Rodrigues Faria Edivaldo Costa Sousa Jr Jamilla A. Pantoja Sueli G. Rodrigues Valéria L. Carvalho Daniele B. A. Medeiros Nazir Savji Guy Baele Marc A. Suchard Philippe Lemey Pedro F. C. Vasconcelos W. Ian Lipkin 《PLoS neglected tropical diseases》2014,8(4)
Dengue virus and its four serotypes (DENV-1 to DENV-4) infect 390 million people and are implicated in at least 25,000 deaths annually, with the largest disease burden in tropical and subtropical regions. We investigated the spatial dynamics of DENV-1, DENV-2 and DENV-3 in Brazil by applying a statistical framework to complete genome sequences. For all three serotypes, we estimated that the introduction of new lineages occurred within 7 to 10-year intervals. New lineages were most likely to be imported from the Caribbean region to the North and Northeast regions of Brazil, and then to disperse at a rate of approximately 0.5 km/day. Joint statistical analysis of evolutionary, epidemiological and ecological data indicates that aerial transportation of humans and/or vector mosquitoes, rather than Aedes aegypti infestation rates or geographical distances, determine dengue virus spread in Brazil. 相似文献
147.
Dereplication by HPLC‐DAD‐ESI‐MS/MS and Screening for Biological Activities of Byrsonima Species (Malpighiaceae)
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148.
Carolina Lessa-Aquino Camila Borges Rodrigues Jozelyn Pablo Rie Sasaki Algis Jasinskas Li Liang Elsio A. Wunder Jr Guilherme S. Ribeiro Adam Vigil Ricardo Galler Douglas Molina Xiaowu Liang Mitermayer G. Reis Albert I. Ko Marco Alberto Medeiros Philip L. Felgner 《PLoS neglected tropical diseases》2013,7(10)
Background
Leptospirosis is a widespread zoonotic disease worldwide. The lack of an adequate laboratory test is a major barrier for diagnosis, especially during the early stages of illness, when antibiotic therapy is most effective. Therefore, there is a critical need for an efficient diagnostic test for this life threatening disease.Methodology
In order to identify new targets that could be used as diagnostic makers for leptopirosis, we constructed a protein microarray chip comprising 61% of Leptospira interrogans proteome and investigated the IgG response from 274 individuals, including 80 acute-phase, 80 convalescent-phase patients and 114 healthy control subjects from regions with endemic, high endemic, and no endemic transmission of leptospirosis. A nitrocellulose line blot assay was performed to validate the accuracy of the protein microarray results.Principal findings
We found 16 antigens that can discriminate between acute cases and healthy individuals from a region with high endemic transmission of leptospirosis, and 18 antigens that distinguish convalescent cases. Some of the antigens identified in this study, such as LipL32, the non-identical domains of the Lig proteins, GroEL, and Loa22 are already known to be recognized by sera from human patients, thus serving as proof-of-concept for the serodiagnostic antigen discovery approach. Several novel antigens were identified, including the hypothetical protein LIC10215 which showed good sensitivity and specificity rates for both acute- and convalescent-phase patients.Conclusions
Our study is the first large-scale evaluation of immunodominant antigens associated with naturally acquired leptospiral infection, and novel as well as known serodiagnostic leptospiral antigens that are recognized by antibodies in the sera of leptospirosis cases were identified. The novel antigens identified here may have potential use in both the development of new tests and the improvement of currently available assays for diagnosing this neglected tropical disease. Further research is needed to assess the utility of these antigens in more deployable diagnostic platforms. 相似文献149.
Batista MN Cuppari L de Fátima Campos Pedrosa L Almeida Md de Almeida JB de Medeiros AC Canziani ME 《Biological trace element research》2006,112(1):1-12
The aim of this study was to compare the nutritional status of zinc and copper in patients with and without diabetes submitted
to chronic hemodialysis. Thirty-three patients with type 2 diabetes (DM group), 30 nondiabetic patients (NDM group), and 20
healthy individuals (control group) were studied. Plasma, erythrocyte, and urinary zinc and plasma copper were obtained from
atomic absorption spectrophotometry and ceruloplasmin by immunonephelometry. The anthropometric parameters were similar among
the groups. Plasma zinc was lower and erythrocyte zinc was higher in the DM and NDM groups in relation to the control group.
No difference in urinary zinc was observed comparing the groups. Plasma copper was higher in the DM group when compared to
the NDM and control groups. Ceruloplasmin was similar in the three groups. Serum urea was a positive independent determinant
of plasma zinc concentrations. The determinants of erythrocyte zinc were MAMC midarm nuscle circumference and Kt/V dialysis
adequacy. The determinants of plasma copper concentration were serum creatinine and serum glucose. The results of this study
demonstrate an alteration in the distribution of zinc of patients with chronic kidney disease (CKD) independently of the presence
of DM. Also, the status of copper seems not to be influenced by CKD, but only by the metabolic derangements associated with
diabetes. 相似文献
150.