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51.
52.
Eriston Vieira Gomes Lucas Breseguello
Do Nascimento Marcos Augusto
De Freitas Luiz Carlos Bhering Nasser Silvana Petrofeza 《Journal of Phytopathology》2011,159(2):94-99
Microsatellites are powerful markers to infer population genetic parameters. We used 10 microsatellite loci to characterize the genetic diversity and structure of 79 samples of Sclerotinia sclerotiorum isolated from four Brazilian dry bean populations and observed that eight of them were polymorphic within populations. We identified 102 different haplotypes ranging from 6 to 18 per locus. Analyses based on genetic diversity and fixation indices indicated variability among and within populations of 28.79% (FST = 28793) and 71.21%, respectively. To examine genetic relatedness among S. sclerotiorum isolates, we used internal spacer (ITS1‐5.8S‐ITS2) restriction fragment length polymorphism (PCR‐RFLP) and sequencing analysis. PCR‐RFLP analysis of these regions failed to show any genetic differences among isolates. However, we detected variability within the sequence, which does not support the hypothesis of clonal populations within each population. High variability within and among populations may indicate the introduction of new genotypes in the areas analysed, in addition to the occurrence of clonal and sexual reproduction in the populations of S. sclerotiorum in the Brazilian Cerrado. 相似文献
53.
Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungus Sporothrix schenckii, which is widely distributed in nature, and presents a saprophytic mycelial form on plant debris and soil. The immunological mechanisms involved in the prevention and control of sporotrichosis are not yet fully understood. In this study, mice were studied after infection with Sporothrix schenckii. In the first week after infection, fungal loading increased and thence decreased drastically 14 days after infection. Analysis by immunoblotting showed that the sera of all mice tested had antibodies reacting only with a 70 kDa antigen, with predominance of IgG1 and IgG3. Taken together, our results show that antigens from S. schenckii induced a specific humoral response in infected mice. 相似文献
54.
Eulália Silva dos Santos Pinheiro Fernanda Costa de Queirós Pedro Montoya Cleber Luz Santos Marion Alves do Nascimento Clara Hikari Ito Manuela Silva David Barros Nunes Santos Silvia Benevides José Garcia Vivas Miranda Katia Nunes Sá Abrah?o Fontes Baptista 《PloS one》2016,11(2)
The main objective of this study is to review and summarize recent findings on electroencephalographic patterns in individuals with chronic pain. We also discuss recent advances in the use of quantitative Electroencephalography (qEEG) for the assessment of pathophysiology and biopsychosocial factors involved in its maintenance over time. Data collection took place from February 2014 to July 2015 in PubMed, SciELO and PEDro databases. Data from cross-sectional studies and longitudinal studies, as well as clinical trials involving chronic pain participants were incorporated into the final analysis. Our primary findings related to chronic pain were an increase of theta and alpha EEG power at rest, and a decrease in the amplitude of evoked potentials after sensory stimulation and cognitive tasks. This review suggests that qEEG could be considered as a simple and objective tool for the study of brain mechanisms involved in chronic pain, as well as for identifying the specific characteristics of chronic pain condition. In addition, results show that qEEG probably is a relevant outcome measure for assessing changes in therapeutic studies. 相似文献
55.
Gisela M. Silva Helena Moreira Silva Joao Nascimento Jean‐Pierre Gonçalves Fernando Pereira Rosa Lima 《Helicobacter》2018,23(5)
Background
The increasing prevalence of Helicobacter pylori (H. pylori) antimicrobial resistance, primarily for clarithromycin decreases the success of treatment. The aim of this study is to determine the local pattern of first‐line antimicrobials resistance and the eradication rate.Material and Methods
Prospective cohort study of H. pylori infected patients (positive histological or cultural exams) treated at Centro Materno‐Infantil do Norte from January of 2013 to October of 2017. Susceptibility to 4 antibiotics: amoxicilin, metronidazole, clarithromycin, and levofloxacin were analyzed by E‐test (phenotypic resistance). The E‐test was chosen because it is simple and cost‐effective for routine susceptibility testing. Point mutations that confer clarithromycin resistance were surveyed (genotypic resistance). Eradication of H. pylori infection was defined by a negative urea breath test or fecal antigen 6‐8 weeks after the end of treatment.Results
Of a total of 74 H. pylori infected patients, 16 were excluded because they had previous H. pylori treatment or severe systemic disease. Median age of infection cases was 15 years (3‐17 years). Eradication regimen used in all patients combined the use of 3 antibiotics (amoxicillin and metronidazole or clarithromycin) and proton pump inibhitor for 14 days and was tailored according antimicrobial susceptibility. 79.5% of the patients completed the treatment. The resistance rate for metronidazole and clarithromycin was 3.3% and 23.3%, respectively. There was no resistance for amoxicilin and levofloxacin. The rate of genotypic resistance to clarithromycin was 37.2%. The eradication rate was 97.8%.Conclusions
The authors found a high resistance rate of H. pylori for clarithromycin in this northern portuguese pediatric center. This factor should determine a change in local current treatment, contraindicating the use of clarithromycin as a first‐line treatment for H. pylori infection in children. The high eradication rate maybe explained for the eradication treatment tailored according antimicrobial susceptibility. 相似文献56.
Lívia Campos Amaral Lins Carolina Nunes França Francisco Antonio Helfenstein Fonseca Simone Pinto Melo Barbosa Lívia Nascimento Matos Ana Carolina Aguirre Henrique Tria Bianco Jonatas Bussador do Amaral Maria Cristina Izar 《Cell biochemistry and biophysics》2014,70(1):687-696
Imbalance on endothelial turnover can predict cardiovascular outcomes. We aimed at evaluating the effects of lipid-modifying therapies on circulating endothelial progenitor cells (EPCs), endothelial microparticles (EMPs), and platelet microparticles (PMPs) in high cardiovascular risk subjects with elevated C-reactive protein (CRP). Sixty-three individuals with coronary heart disease (CHD) or CHD risk equivalent on stable statin therapy, with LDL-cholesterol <100 mg/dL and CRP ≥2.0 mg/L were selected. After a 4-week run-in period with atorvastatin 10 mg, those with persistent CRP ≥2.0 mg/L were randomized to another 4-week treatment period with atorvastatin 40 mg, ezetimibe 10 mg or atorvastatin 40 mg/ezetimibe 10 mg. EPC (CD34+/CD133+/KDR+), EMP (CD51+), and PMP (CD42+/CD31+) were quantified by flow cytometry. Atorvastatin 40 mg and atorvastatin 40 mg/ezetimibe 10 mg reduced LDL-cholesterol (P < 0.001, paired T test, vs. baseline). Combined therapy, but not ezetimibe reduced CRP. CD34+/KDR+ EPC were reduced after ezetimibe alone (P = 0.011 vs. baseline, Wilcoxon test) or combined with atorvastatin (P = 0.016 vs. baseline, Wilcoxon test). In addition, ezetimibe increased CD51+ EMP (P = 0.017 vs. baseline, Wilcoxon test). No correlations between these markers and LDL-cholesterol or CRP were observed. These results contribute to understand the link between inflammation and vascular homeostasis and highlight the broader benefit of statins decreasing inflammation and preventing microparticles release, an effect not observed with ezetimibe alone. 相似文献
57.
Mahasweta Saha Francisco R. Barboza Paul J. Somerfield Balsam Al‐Janabi Miriam Beck Janina Brakel Maysa Ito Christian Pansch Jennifer C. Nascimento‐Schulze Stina Jakobsson Thor Florian Weinberger Yvonne Sawall 《Global Change Biology》2020,26(2):417-430
Marine heatwaves have been observed worldwide and are expected to increase in both frequency and intensity due to climate change. Such events may cause ecosystem reconfigurations arising from species range contraction or redistribution, with ecological, economic and social implications. Macrophytes such as the brown seaweed Fucus vesiculosus and the seagrass Zostera marina are foundation species in many coastal ecosystems of the temperate northern hemisphere. Hence, their response to extreme events can potentially determine the fate of associated ecosystems. Macrophyte functioning is intimately linked to the maintenance of photosynthesis, growth and reproduction, and resistance against pathogens, epibionts and grazers. We investigated morphological, physiological, pathological and chemical defence responses of western Baltic Sea F. vesiculosus and Z. marina populations to simulated near‐natural marine heatwaves. Along with (a) the control, which constituted no heatwave but natural stochastic temperature variability (0HW), two treatments were applied: (b) two late‐spring heatwaves (June, July) followed by a summer heatwave (August; 3HW) and (c) a summer heatwave only (1HW). The 3HW treatment was applied to test whether preconditioning events can modulate the potential sensitivity to the summer heatwave. Despite the variety of responses measured in both species, only Z. marina growth was impaired by the accumulative heat stress imposed by the 3HW treatment. Photosynthetic rate, however, remained high after the last heatwave indicating potential for recovery. Only epibacterial abundance was significantly affected in F. vesiculosus. Hence both macrophytes, and in particular F. vesiculosus, seem to be fairly tolerant to short‐term marine heatwaves at least at the intensities applied in this experiment (up to 5°C above mean temperature over a period of 9 days). This may partly be due to the fact that F. vesiculosus grows in a highly variable environment, and may have a high phenotypic plasticity. 相似文献
58.
The microenvironment of the iron in a sea turtle Dermochelys coriacea myoglobin is studied using the spectroscopic techniques EPR and optical absorption. Optical absorption spectra in the visible region suggest a great homology between turtle Mb and other myoglobins, such as those from whale, human and elephant. The pK of the acid-alkaline transition is 8.4 slightly lower than the pK of whale and equal to that of elephant myoglobin. The EPR spectrum at pH 7.0 is characteristic of a high-spin configuration with axial symmetry (gx = gy = 5.95). At higher pH, this signal changes in a way different from that observed for whale myoglobin. We observe for turtle Mb both the formation of a low-spin configuration with rhombic symmetry (gx = 2.56, gy = 2.20, gz = 1.90) and of a high-spin species with rhombic distortion (gx = 6.79, gy = 5.18, gz = 2.12). This suggests a lowering of symmetry at the haem, so that now the x and y directions are no more equivalent. This can be explained by amino acid substitution at the distal positions of haem or to off-axial positioning of distal residues. The coexistence at high pH (pH 11.0) of these two spin forms could be explained by the existence of two protein conformations, in which the crystal field splitting factor, delta, and the electron exchange energy are of the same order, allowing the presence of different configurations simultaneously. The presence of different kinds of haem is ruled out by the experiments with nitrosyl turtle Mb and turtle Mb-F showing spectra very similar to those of whale myoglobin. The pk of the acid-alkaline transition, 8.5, obtained from EPR spectra, agrees very well with results from optical absorption. 相似文献
59.
Binding to a specific receptor is an essential step for most enteropathogens to initiate an intestinal infection. We analyzed the inhibitory effect of human milk and its protein components on adhesion of two diarrheagenic Escherichia coli strains, diffusely adherent E. coli (DAEC) and enteroaggregative E. coli (EAEC), to HeLa cells. Defatted milk, whey proteins, immunoglobulin and non-immunoglobulin fractions, in concentrations lower than usually found in whole milk, inhibited both DAEC and EAEC adhesion, indicating that human milk components may contribute to the defense of the infants against enteropathogens. 相似文献
60.
Sampaio WO Nascimento AA Santos RA 《American journal of physiology. Heart and circulatory physiology》2003,284(6):H1985-H1994
The systemic and regional hemodynamics effects of ANG-(1-7) were examined in urethane-anesthetized rats. The blood flow distribution (kidneys, skin, mesentery, lungs, spleen, brain, muscle, and adrenals), cardiac output, and total peripheral resistance were investigated by using fluorescent microspheres. Blood pressure and heart rate were recorded from the brachial artery. ANG-(1-7) infusion (110 fmol x min(-1) x 10 min(-1) iv) significantly increased blood flow to the kidney (5.10 +/- 1.07 to 8.30 +/- 0.97 ml x min(-1) x g(-1)), mesentery (0.73 +/- 0.16 to 1.17 +/- 0.49 ml x min(-1) x g(-1)), brain (1.32 +/- 0.44 to 2.18 +/- 0.85 ml x min(-1) x g(-1)), and skin (0.07 +/- 0.02 to 0.18 +/- 0.07 ml x min(-1) x g(-1)) and the vascular conductance in these organs. ANG-(1-7) also produced a significant increase in cardiac index (30%) and a decrease in total peripheral resistance (2.90 +/- 0.55 to 2.15 +/- 0.28 mmHg x ml(-1) x min x 100 g). Blood flow to the spleen, muscle, lungs, and adrenals, as well as the blood pressure and heart rate, were not altered by the ANG-(1-7) infusion. The selective ANG-(1-7) antagonist A-779 reduced the blood flow in renal, cerebral, mesenteric, and cutaneous beds and blocked the ANG-(1-7)-induced vasodilatation in the kidney, mesentery, and skin, suggesting a significant role of endogenous ANG-(1-7) in these territories. The effects of ANG-(1-7) on the cerebral blood flow, cardiac index, systolic volume, and total peripheral resistance were partially attenuated by A-779. A high dose of ANG-(1-7) (11 pmol x min(-1) x 10 min(-1)) caused an opposite effect of that produced by the low dose. Our results show for the first time that ANG-(1-7) has a previously unsuspected potent effect in the blood flow distribution and systemic hemodynamics. 相似文献