171 resultados para Matched labelling


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The role of exercise training (ET) on cardiac renin-angiotensin system (RAS) was investigated in 3-5 month-old mice lacking alpha(2A-) and alpha(2C-)adrenoceptors (alpha(2A)/alpha(2C)ARKO) that present heart failure (HF) and wild type control (WT). ET consisted of 8-week running sessions of 60 min, 5 days/week. In addition, exercise tolerance, cardiac structural and function analysis were made. At 3 months, fractional shortening and exercise tolerance were similar between groups. At 5 months, alpha(2A)/alpha(2C)ARKO mice displayed ventricular dysfunction and fibrosis associated with increased cardiac angiotensin (Ang) II levels (2.9-fold) and increased local angiotensin-converting enzyme activity (ACE 18%). ET decreased alpha(2A)/alpha(2C)ARKO cardiac Ang II levels and ACE activity to age-matched untrained WT mice levels while increased ACE2 expression and prevented exercise intolerance and ventricular dysfunction with little impact on cardiac remodeling. Altogether, these data provide evidence that reduced cardiac RAS explains, at least in part, the beneficial effects of ET on cardiac function in a genetic model of HF.

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beta-blockers, as class, improve cardiac function and survival in heart failure (HF). However, the molecular mechanisms underlying these beneficial effects remain elusive. In the present study, metoprolol and carvedilol were used in doses that display comparable heart rate reduction to assess their beneficial effects in a genetic model of sympathetic hyperactivity-induced HF (alpha(2A)/alpha(2C)-ARKO mice). Five month-old HF mice were randomly assigned to receive either saline, metoprolol or carvedilol for 8 weeks and age-matched wild-type mice (WT) were used as controls. HF mice displayed baseline tachycardia, systolic dysfunction evaluated by echocardiography, 50% mortality rate, increased cardiac myocyte width (50%) and ventricular fibrosis (3-fold) compared with WT. All these responses were significantly improved by both treatments. Cardiomyocytes from HF mice showed reduced peak [Ca(2+)](i) transient (13%) using confocal microscopy imaging. Interestingly, while metoprolol improved [Ca(2+)](i) transient, carvedilol had no effect on peak [Ca(2+)](i) transient but also increased [Ca(2+)] transient decay dynamics. We then examined the influence of carvedilol in cardiac oxidative stress as an alternative target to explain its beneficial effects. Indeed, HF mice showed 10-fold decrease in cardiac reduced/oxidized glutathione ratio compared with WT, which was significantly improved only by carvedilol treatment. Taken together, we provide direct evidence that the beneficial effects of metoprolol were mainly associated with improved cardiac Ca(2+) transients and the net balance of cardiac Ca(2+) handling proteins while carvedilol preferentially improved cardiac redox state. (C) 2008 Elsevier Inc. All rights reserved.

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A niobium single crystal was subjected to equal channel angular pressing (ECAP) at room temperature after orienting the crystal such that [1 -1 -1] ayen ND, [0 1 -1] ayen ED, and [-2 -1 -1] ayen TD. Electron backscatter diffraction (EBSD) was used to characterize the microstructures both on the transverse and the longitudinal sections of the deformed sample. After one pass of ECAP the single crystal exhibits a group of homogeneously distributed large misorientation sheets and a well formed cell structure in the matrix. The traces of the large misorientation sheets match very well with the most favorably oriented slip plane and one of the slip directions is macroscopically aligned with the simple shear plane. The lattice rotation during deformation was quantitatively estimated through comparison of the orientations parallel to three macroscopic axes before and after deformation. An effort has been made to link the microstructure with the initial crystal orientation. Collinear slip systems are believed to be activated during deformation. The full constraints Taylor model was used to simulate the orientation evolution during ECAP. The result matched only partially with the experimental observation.

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This paper presents an analysis of the performance of a baseband multiple-input single-output (MISO) time reversal ultra-wideband system (TR-UWB) incorporating a symbol spaced decision feedback equalizer (DFE). A semi-analytical performance analysis based on a Gaussian approach is considered, which matched well with simulation results, even for the DFE case. The channel model adopted is based on the IEEE 802.15.3a model, considering correlated shadowing across antenna elements. In order to provide a more realistic analysis, channel estimation errors are considered for the design of the TR filter. A guideline for the choice of equalizer length is provided. The results show that the system`s performance improves with an increase in the number of transmit antennas and when a symbol spaced equalizer is used with a relatively small number of taps compared to the number of resolvable paths in the channel impulse response. Moreover, it is possible to conclude that due to the time reversal scheme, the error propagation in the DFE does not play a role in the system`s performance.

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Background: Chronic Kidney Disease (CKD) patients present high levels of electronegative LDL (LDL) that can modulate the expression of molecules involved in inflammation and it is closely linked to atherosclerosis. We investigated the association between LDL(-) and inflammatory markers in patients undergoing hemodialysis (HD). Methods: Forty-seven HD patients from a private clinic in Rio de Janeiro, Brazil were studied and compared with 20 age matched healthy individuals. Serum LDL(-) and anti-LDL(-) autoantibody levels were measured by ELISA; TNF-alpha, IL-6, VCAM-1 and ICAM-1 were determined by a multiplex assay kit. Results: HD patients presented higher IL-6 and TNF-alpha concentrations (4.1 +/- 1.6 and 5.5 +/- 2.1 pg/ml, respectively) than healthy subjects (2.6 +/- 0.2 and 2.4 +/- 1.1 pg/ml, respectively) (p = 0.0001). In addition, they presented higher VCAM-1 and ICAM-1 levels and, LDL(-) concentrations were also increased (0.18 +/- 0.12 U/I) when compared to healthy individuals (0.10 +/- 0.08 U/I) (p<0.02). In contrast, the anti-LDL(-) autoantibody levels were lower in HD patients (0.02 +/- 0.01 mg/l) than in healthy subjects (0.05 +/- 0.03 mg/l) (p<0.001). There was a positive correlation between LDL(-) and IL-6 (r = 0.25, p = 0.004) and ICAM-1 (r = 0.36; p = 0.003). There was also a negative correlation between anti-LDL(-) autoantibodies and TNF-alpha (r = -0.37; p = 0.003) and VCAM-1 (r = -0.50; p = 0.0001). Conclusions: The association between LDL(-) and inflammation and the lower levels of anti-LDL(-) autoantibodies are important risk factors related to atherosclerosis in CKD. (C) 2011 Published by Elsevier B.V.

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NUNES ALVES, M. J. N., M. R. DOS SANTOS, R. G. DIAS, C. A. AKIHO, M. C. LATERZA, M. U. P. B. RONDON, R. L. DE MORAES MOREAU, and C. E. NEGRAO. Abnormal Neurovascular Control in Anabolic Androgenic Steroids Users. Med. Sci. Sports Exerc., Vol. 42, No. 5, pp. 865-871, 2010. Purpose: Previous studies showed that anabolic androgenic steroids (AAS) increase vascular resistance and blood pressure (BP) in humans. In this study, we tested the hypotheses 1) that AAS users would have increased muscle sympathetic nerve activity (MSNA) and reduced forearm blood flow (FBF) compared with AAS nonusers and 2) that there would be an association between MSNA and 24-h BP. Methods: Twelve AAS users aged 31 +/- 2 yr (means +/- SE) and nine age-matched AAS nonusers aged 29 T 2 yr participated in the study. All individuals were involved in strength training for at least 2 yr. AAS was determined by urine test (chromatography-mass spectrometry). MSNA was directly measured by microneurography technique. FBF was measured by venous occlusion plethysmography. BP monitoring consisted of measures of BP for 24 h. Results: MSNA was significantly higher in AAS users than that in AAS nonusers (29 +/- 3 vs 20 +/- 1 bursts per minute, P = 0.01). FBF (1.92 +/- 0.17 vs 2.77 +/- 0.24 mL.min(-1).100 mL(-1), P = 0.01) and forearm vascular conductance (2.01 +/- 0.17 vs 2.86 +/- 0.31 U, P = 0.02) were significantly lower in AAS users than that in AAS nonusers. Systolic (131 +/- 4 vs 120 +/- 3 mm Hg, P = 0.001), diastolic (74 +/- 4 vs 68 +/- 3 mm Hg, P = 0.02), and mean BP (93 +/- 4 vs 86 +/- 3 mm Hg, P = 0.005) and heart rate (74 +/- 3 vs 68 +/- 3 bpm, P = 0.02) were significantly higher in AAS users when compared with AAS nonusers. Further analysis showed that there was a significant correlation between MSNA and 24-h mean BP (r = 0.75, P = 0.002). Conclusions: AAS increases MSNA and reduces muscle blood flow in young individuals. In addition, the increase in BP levels in AAS users is associated with augmented sympathetic outflow. These findings suggest that AAS increases the susceptibility for cardiovascular disease in humans.

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In a study conducted in Joao Pessoa, northeast of Brazil, 2344 Escherichia coli isolated from 290 infants with diarrhea and 290 healthy matched controls were analyzed for virulence traits. Enteroaggregative E. coli (EAEC) was the most prevalent pathogen associated to acute diarrhea. Based on the results of colony blot hybridization, serotyping, and HEp-2 cell adherence assays, strains were separated in categories as typical enteropathogenic E. coli (EPEC) (1.7%), atypical EPEC (a-EPEC) (9.3%), EAEC (25%), enterotoxigenic E. coli (10%), and enteroinvasive E. coli (EIEC) (1.4%). No enterohemorrhagic E. coli strains were isolated. Other enteropathogens were found, including Salmonella (7.9%), Shigella spp. (4.1%), thermophilic Campylobacter spp. (2.4%), Giardia lamblia (9.3%), and Entamoeba histolytica (5.8%). All enteropathogens were associated with diarrhea (P < 0.01). However, the association was lower for EPEC and EIEC (P < 0.03). Different pathogens associated with diarrhea may have been changing in Brazil where EAEC and a-EPEC seem to be the most prevalent pathogens among them. (C) 2010 Elsevier Inc. All rights reserved.

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A graph clustering algorithm constructs groups of closely related parts and machines separately. After they are matched for the least intercell moves, a refining process runs on the initial cell formation to decrease the number of intercell moves. A simple modification of this main approach can deal with some practical constraints, such as the popular constraint of bounding the maximum number of machines in a cell. Our approach makes a big improvement in the computational time. More importantly, improvement is seen in the number of intercell moves when the computational results were compared with best known solutions from the literature. (C) 2009 Elsevier Ltd. All rights reserved.

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The present study used a temporal bisection task to investigate whether music affects time estimation differently from a matched auditory neutral stimulus, and whether the emotional valence of the musical stimuli (i.e., sad vs. happy music) modulates this effect. The results showed that, compared to sine wave control music, music presented in a major (happy) or a minor (sad) key shifted the bisection function toward the right, thus increasing the bisection point value (point of subjective equality). This indicates that the duration of a melody is judged shorter than that of a non-melodic control stimulus, thus confirming that ""time flies"" when we listen to music. Nevertheless, sensitivity to time was similar for all the auditory stimuli. Furthermore, the temporal bisection functions did not differ as a function of musical mode. (C) 2010 Elsevier B.V. All rights reserved.

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Withdrawal from morphine leads to the appearance of extreme anxiety accompanied of several physical disturbances, most of them linked to the activation of brainstem regions such as the locus coeruleus, ventral tegmental area, hypothalamic nuclei and periaqueductal grey (PAG). As anxiety remains one of the main components of morphine withdrawal the present study aimed to evaluating the influence of the dorsal aspects of the PAG on the production of this state, since this structure is well-known to be involved in defensive behaviour elicited by anxiety-evoking stimuli. Different groups of animals were submitted to 10 days of i.p. morphine injections, challenged 2 h after with an i.p. injection of naloxone (0.1 mg/kg), and submitted to the plus-maze, open-field and light-dark transition tests. The effects of morphine withdrawal on anxiety-induced Fos immunolabelling were evaluated in four animals that passed by the light-dark transition test randomly chosen for Fos-protein analysis. Besides the PAG, Fos neural expression was conducted in other brain regions involved in the expression of anxiety-related behaviours. Our results showed that morphine withdrawn rats presented enhanced anxiety accompanied of few somatic symptoms. Increased Fos immunolabelling was noted in brain regions well-known to modulate these states as the prelimbic cortex, nucleus accumbens, amygdala and paraventricular hypothalamus. Increased Fos labelling was also observed in the ventral and dorsal aspects of the PAG, a region involved in anxiety-related processes suggesting that this region could be a common neural substrate enlisted during anxiety evoked by dangerous stimuli as well as those elicited by opiate withdrawal. (c) 2008 Elsevier Inc. All rights reserved,

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Objective: To evaluate patients with Diabetes Mellitus type 2 and painful peripheral neuropathy in order to investigate oral complaints and facial somatosensory findings. Research design and methods: Case-control study; 29 patients (12 women, mean age 57.86 yo) with Diabetes Mellitus type 2 and 31 age-gender-matched controls were evaluated with a standardized protocol for general characteristics, orofacial pain, research diagnostic criteria for temporomandibular disorders, visual analogue scale and McGill Pain questionnaire, and a systematic protocol of quantitative sensory testing for bilateral facial sensitivity at the areas innervated by the trigeminal branches, which included the thermal detection by ThermoSensi 2, tactile evaluation with vonFrey filaments, and superficial pain thresholds with a superficial algometer (Micromar). Statistical analysis was performed with Wilcoxon, chi-square, confidence intervals and Spearman (p < 0.05). Results: Orofacial pain was reported by 55.2% of patients, and the most common descriptor was fatigue (50%); 17.2% had burning mouth. Myofascial temporomandibular disorders were diagnosed in 9(31%) patients. The study group showed higher sensory thresholds of pain at the right maxillary branch (p = 0.017) but sensorial differences were not associated with pain (p = 0.608). Glycemia and HbA(1c) were positively correlated with the quantitative sensory testing results of pain (p < 0.05) and cold (p = 0.044) perceptions. Higher pain thresholds were correlated with higher glycemia and glycated hemoglobin (p = 0.027 and p = 0.026). Conclusions: There was a high prevalence of orofacial pain and burning mouth was the most common complaint. The association of loss of pain sensation and higher glycemia and glycated hemoglobin can be of clinical use for the follow-up of DM complications. (C) 2010 Elsevier Ltd. All rights reserved.

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Objectives: The relationship between saddle nose deformity (SND) in Wegener`s granulomatosis (WG) and other clinical features, including retro-orbital mass formation (ROM), has been poor described. Therefore, this relationship was analyzed retrospectively from 2000 to 2010. Patients and Methods: Eighteen consecutive WG patients with SND diagnosed by computed tomography were matched to 36 WG patients without SND (control group) for gender, age at WG diagnosis and disease duration. Results: No difference was found between the two groups in relation to WG type (limited and systemic forms), ethnicity, laboratory features, constitutional symptoms or clinical manifestations, including upper respiratory tract, and treatment, except for ROM (33.3 vs. 2.8% in SND(+) and SND(-) groups, respectively; p=0.004) and subglottic stenosis (22.2 vs. 2.8%; p=0.038). However, on multivariate analysis, only ROM (OR 17.15; 95% CI 1.11-265.52) was statistically associated to SND. In addition, in more than half of the cases, SND manifested prior to ROM. Conclusions: Results of this prospective analysis showed that SND was strongly associated to ROM in WG. Since early diagnosis and aggressive treatment of orbital involvement could lead to better prognosis, the presence of SND warrants additional vigilance.

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Objective. To develop a questionnaire for the evaluation of sexuality of male patients with juvenile idiopathic arthritis (JIA). Methods. A cohort of male patients with rheumatoid factor (RF)-negative polyarticular. JIA according to the 2004 revised ILAR criteria and inactive disease was Studied. The Health Assessment Questionnaire (HAQ) was applied to all patients. As a control group, 120 age-matched males of the same socioeconomic status were evaluated. A self-administered Structured instrument, the Male Sexual Evaluation Questionnaire (MSEQ), was developed by multiprofessional experts to assess sexual life, including satisfaction, practice. and related functional aspects. Results. Thirty-two male patients with RF-negative polyarticular JIA [mean age 20.8 +/- 3.8 yrs (range 16-26), mean disease duration 15.4 +/- 3.6 yrs (range 13-20)] were studied. Mean HAQ score was 1.25 +/- 0.67 (range 0.1-2.1). Masturbation was practiced similarly by patients and controls (87.5% vs 91%; p > 0.999), although joint pain was observed in only 2 (7%) patients. Regular sexual intercourse (>= once/week) was reported by 78% of patients and 62% of controls (p = 0.86). Joint pain during intercourse was more frequent in patients (48% vs 3% in controls; p < 0.001). The mean HAQ score was higher in the 12 patients with,joint pain (hips = 3, knees = 5, and hips + knees = 4) during intercourse compared to the 13 patients without joint pain (1.82 +/- 0.27 vs 1.43 +/- 0.32; p < 0.05). Preserved desire and satisfaction were universal findings for all JIA patients and controls. Conclusion. The MSEQ was applicable to this cohort of male patients with RF-negative polyarticular JIA and showed that sexual life is preserved despite longterm disease, morbidity/functional dysfunction, and joint pain. (First Release May 1 2009: J Rheumatol 2009;36: 1337-42; doi: 10.3899/jrheum.080867)

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Precis Women with recurrent vulvovaginal candidiasis (RVC) due to a polymorphism in codon 54 of the MBL2 gene respond better to fluconazole maintenance therapy than do women with other underlying causes. Objective To explain differences in response rates to maintenance therapy with fluconazole in women suffering from RVC by evaluating associations with a polymorphism in the gene coding for mannose-binding lectin (MBL). Design Follow-up study, neted case-control group. Setting Women attending vulvoginitis clinic for RVC. Population Women participating in a multicentric study in Belgium with a degressive dose of fluconazole for RVC (the ReCiDiF trial) were divided into good responders, intermediate responders and nonresponders according to the number of relapses they experienced during therapy. From 109 of these women with adequate follow-up data, vaginal lavage with 2 ml of saline were performed at the moment of a proven acute attack at inclusion in the study, before maintenance treatment was started. A buccal swab was obtained from 55 age-matched women without a history of Candida infections, serving as a control group. Methods Extracted DNA from buccal or vaginal cells was tested for codon 54 MBL2 gene polymorphism by polymerase chain reaction and endonuclease digestion. Main outcome measures Frequency of MBL2 condon 54 allele B in women with optimal or poor response to maintenance therapy in composition with controls. Results Women (n = 109) suffering from RVC were more likely to carry the variant MBL2 codon 54 allele B than control women (20 versus 6.6%, OR 3.4 [95% CI 1.3-8.2], P = 0.01). B alleles were present in 25% of the 36 women not suffering from any recurrence during the maintenance therapy with decreasing doses of fluconazole (OR 4.9 [95% CI 1.9-12.5], P = 0.0007 versus controls), in 20% of the 43 women with sporadic recurrences (OR 3.6 [95% CI 1.4-9.2], P = 0.007 versus controls) and in 15% of the 30 women who had to interrupt the treatment regimen due to frequent relapses (P = 0.097 versus controls). Conclusions The MBL2 codon 54 gene polymorphism is more frequent in Belgian women suffering from RVC than in controls. The presence of the B allele is associated with a superior response to fluconazole maintenance therapy as compared with RVC patients without this polymorphism. We conclude that RVC due to deficient MBL production is more easily helped with antifungal medication than is RVC due to some other mechanism.

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Objective: To evaluate the association between parkinsonism and mutations in the glucocerebrosidase gene (GBA) in Brazilian patients. Methods: We searched for three GBA common mutations (N370S, L444P and G377S) in 65 Brazilian patients affected by PD with disease onset before the age of 55 and compared the results to 267 age- and sex-matched controls. Results: GBA mutations were detected at a significantly higher frequency among Parkinson`s disease patients (2/65 = 3%), when compared to the control group (0/267): P = 0.0379. Conclusion: These results provide further evidence for GBA mutations being a possible hereditary risk factor for PD. (C) 2007 Elsevier Ltd. All rights reserved.