194 resultados para value distribution


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Real time three-dimensional echocardiography (RT3DE) has been demonstrated to be an accurate technique to quantify left ventricular (LV) volumes and function in different patient populations. We sought to determine the value of RT3DE for evaluating patients with hypertrophic cardiomyopathy (HCM), in comparison with cardiac magnetic resonance imaging (MRI). Methods: We studied 20 consecutive patients with HCM who underwent two-dimensional echocardiography (2DE), RT3DE, and MRI. Parameters analyzed by echocardiography and MRI included: wall thickness, LV volumes, ejection fraction (LVEF), mass, geometric index, and dyssynchrony index. Statistical analysis was performed by Lin agreement coefficient, Pearson linear correlation and Bland-Altman model. Results: There was excellent agreement between 2DE and RT3DE (Rc = 0.92), 2DE and MRI (Rc = 0.85), and RT3DE and MRI (Rc = 0.90) for linear measurements. Agreement indexes for LV end-diastolic and end-systolic volumes were Rc = 0.91 and Rc = 0.91 between 2DE and RT3DE, Rc = 0.94 and Rc = 0.95 between RT3DE and MRI, and Rc = 0.89 and Rc = 0.88 between 2DE and MRI, respectively. Satisfactory agreement was observed between 2DE and RT3DE (Rc = 0.75), RT3DE and MRI (Rc = 0.83), and 2DE and MRI (Rc = 0.73) for determining LVEF, with a mild underestimation of LVEF by 2DE, and smaller variability between RT3DE and MRI. Regarding LV mass, excellent agreement was observed between RT3DE and MRI (Rc = 0.96), with bias of -6.3 g (limits of concordance = 42.22 to -54.73 g). Conclusion: In patients with HCM, RT3DE demonstrated superior performance than 2DE for the evaluation of myocardial hypertrophy, LV volumes, LVEF, and LV mass.

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Background. Many resource-limited countries rely on clinical and immunological monitoring without routine virological monitoring for human immunodeficiency virus (HIV)-infected children receiving highly active antiretroviral therapy (HAART). We assessed whether HIV load had independent predictive value in the presence of immunological and clinical data for the occurrence of new World Health Organization (WHO) stage 3 or 4 events (hereafter, WHO events) among HIV-infected children receiving HAART in Latin America. Methods. The NISDI (Eunice Kennedy Shriver National Institute of Child Health and Human Development International Site Development Initiative) Pediatric Protocol is an observational cohort study designed to describe HIV-related outcomes among infected children. Eligibility criteria for this analysis included perinatal infection, age ! 15 years, and continuous HAART for >= 6 months. Cox proportional hazards modeling was used to assess time to new WHO events as a function of immunological status, viral load, hemoglobin level, and potential confounding variables; laboratory tests repeated during the study were treated as time-varying predictors. Results. The mean duration of follow-up was 2.5 years; new WHO events occurred in 92 (15.8%) of 584 children. In proportional hazards modeling, most recent viral load 15000 copies/mL was associated with a nearly doubled risk of developing a WHO event (adjusted hazard ratio, 1.81; 95% confidence interval, 1.05-3.11; P = 033), even after adjustment for immunological status defined on the basis of CD4 T lymphocyte value, hemoglobin level, age, and body mass index. Conclusions. Routine virological monitoring using the WHO virological failure threshold of 5000 copies/mL adds independent predictive value to immunological and clinical assessments for identification of children receiving HAART who are at risk for significant HIV-related illness. To provide optimal care, periodic virological monitoring should be considered for all settings that provide HAART to children.

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P>Background Congenital adrenal hyperplasia caused by classic 21-hydroxylase deficiency (21OHD) is an autosomal recessive disorder with a high prevalence of asymptomatic heterozygote carriers (HTZ) in the general population, making case detection desirable by routine methodology. HTZ for classic and nonclassic (NC) forms have basal and ACTH-stimulated values of 17-hydroxyprogesterone (17OHP) that fail to discriminate them from the general population. 21-Deoxycortisol (21DF), an 11-hydroxylated derivative of 17OHP, is an alternative approach to identify 21OHD HTZ. Objective To determine the discriminating value of basal and ACTH-stimulated serum levels of 21DF in comparison with 17OHP in a population of HTZ for 21OHD (n = 60), as well as in NC patients (n = 16) and in genotypically normal control subjects (CS, n = 30), using fourth generation tandem mass spectrometry after HPLC separation (LC-MS/MS). Results Basal 21DF levels were not different between HTZ and CS, but stimulated values were increased in the former and virtually nonresponsive in CS. Only 17 center dot 7% of the ACTH-stimulated 21DF levels overlapped with CS, when compared to 46 center dot 8% for 17OHP. For 100% specificity, the sensitivities achieved for ACTH-stimulated 21DF, 17OHP and the quotient [(21DF + 17OHP)/F] were 82 center dot 3%, 53 center dot 2% and 87%, using cut-offs of 40, 300 ng/dl and 46 (unitless), respectively. Similar to 17OHP, ACTH-stimulated 21DF levels did not overlap between HTZ and NC patients. A positive and highly significant correlation (r = 0 center dot 846; P < 0 center dot 001) was observed between 21DF and 17OHP pairs of values from NC and HTZ. Conclusion This study confirms the superiority of ACTH-stimulated 21DF, when compared to 17OHP, both measured by LC-MS/MS, in identifying carriers for 21OHD. Serum 21DF is a useful tool in genetic counselling to screen carriers among relatives in families with affected subjects, giving support to molecular results.

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The antichromatin antibody (aCT) has been described as a useful marker for lupus nephropathy. The relevance of its nephritogenic potential may be appropriately evaluated in the context of renal histopathology. Therefore, the present study investigated the relationship of aCT with a particular histopathologic class of lupus nephritis (LN). Seventy-eight consecutive patients with systemic lupus erythematosus (ACR criteria) and active nephritis who underwent renal biopsy from 1999 to 2004 and with available frozen serum sample obtained at the time of biopsy were selected. aCT was measured by ELISA, and anti-dsDNA was measured by indirect immunofluorescence (IIF) and by ELISA. All renal biopsies were revised in a blinded manner by the same expert renal pathologist. Charts were extensively reviewed for demographic and renal features obtained at the time of biopsy. The prevalence of aCT (>= 20 U) was 59% with a mean titer of 74.3 +/- 38.7U. Both aCT-positive and aCT-negative groups of patients had similar age, gender distribution, duration of lupus, and duration of renal disease. Anti-dsDNA was detected by IIF in 29.5% and by ELISA in 42.3% of the patients. Concomitant presence of both antibodies was observed in 63% (29/46) [anti-dsDNA by ELISA] and 45.6% (21/46) [anti-dsDNA by IIF] of the patients. Lower serum levels of C3 (73% vs. 40%, P=0.0058) and C4 (82% vs. 46.7%, P=0.0021) were more commonly observed in aCT >= 20 U patients compared to the aCT-negative group. It is important to note that the use of a higher cut-off value (>= 40 U) for aCT test revealed a predominance of class IV LN (58% vs. 33%, P=0.039) in aCT >= 40 U compared to aCT<40 U group. The mean levels of proteinuria, serum albumin, and creatinine were markedly altered but were comparable in both groups (P >= 0.05). One fourth (26.3%) of the 19 patients with class IV LN and aCT >= 40 U had no detectable anti-dsDNA (ELISA). These data suggest that high-titer aCT seems to be a valuable biomarker for proliferative class IV of LN.

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Background and aims: HDL-cholesterol (HDL-C) and non-HDL-cholesterol (nHDL-C) are involved in atherosclerosis. The aim of this study was to determine the distribution of HDL-C and nHDL-C and its association with cardiovascular and socio-cultural variables in a pediatric Brazilian sample. Methods and results: Children and adolescents from Florianopolis were randomly selected and a structured questionnaire was administered, a physical examination was performed and a blood sample was collected. Enzymatic and Direct methods in vitro were used to determine the total cholesterol and HDL-cholesterol levels. The associations among HDL-C and nHDL-C and the described variables were tested by odds ratio and logistic regression. A total of 1009 individuals were examined. Based on the Brazilian criteria, 23% were classified with low levels of HDL-C and 25% with high levels of non-HDL-C. After multivariate analysis there were significant associations among low HDL-C and high C-reactive protein (OR, 3.3; 95% CI, 2.1-5.2), paternal tobacco use (OR, 1.5; 95% CI, 1.1-2.1), and high triceps-to-subscapular index (OR, 1.5; 95% CI, 1.1-2.2). There were also significant associations among high nHDL-C and high waist circumference (OR, 1.95; 95% CI, 1.16-3.29), black skin color (OR, 1.78; 95% CI, 1.06-3.06), and high income (OR, 1.48; 95% CI, 1.09-2.02). Conclusions: In this sample, low levels of HDL-C were associated with other clinical variables such as a centripetal fat pattern and C-reactive protein, and n-HDL-C was associated with abdominal obesity, skin color and economic class. (C) 2009 Elsevier B. V. All rights reserved.

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Background. Acute mesenteric ischemia is a potentially fatal vascular emergency with mortality rates ranging between 60% and 80%. Several studies have extensively examined the hemodynamic and metabolic effects of superior mesenteric artery occlusion. On the other hand, the cardiocirculatory derangement and the tissue damage induced by intestinal outflow obstruction have not been investigated systematically. For these reasons we decided to assess the initial impact of venous mesenteric occlusion on intestinal blood flow distribution, and correlate these findings with other systemic and regional perfusion markers. Methods. Fourteen mongrel dogs were subjected to 45 min of superior mesenteric artery (SMAO) or vein occlusion (SMVO), and observed for 120 min after reperfusion. Systemic hemodynamics were evaluated using Swan-Ganz and arterial catheters. Regional blood flow (ultrasonic flow probes), intestinal O(2)-derived variables, and mesenteric-arterial and tonometric-arterial pCO(2) gradients (D(mv-a)pCO(2) and D(t-a)pCO(2)) were also calculated. Results. SMVO was associated with hypotension and low cardiac output. A significant increase in the regional pCO(2) gradients was also observed in both groups during the ischemic period. After reperfusion, a progressive reduction in D(mv-a)pCO(2) occurred in the SMVO group; however, no improvement in D(t-p)CO(2) was observed. The histopathologic injury scores were 2.7 +/- 0.5 and 4.8 +/- 0.2 for SMAO and SMVO, respectively. Conclusions. SMV occlusion promoted early and significant hemodynamic and metabolic derangement at systemic and regional levels. Additionally, systemic pCO(2) gradient is not a reliable parameter to evaluate the local intestinal oxygenation. Finally, the D(t-a)pCO(2) correlates with histologic changes during intestinal congestion or ischemia. However, minor histologic changes cannot be detected using this methodology. (C) 2010 Elsevier Inc. All rights reserved.

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Background Left atrial volume indexed (LAVI) has been reported as a predictor of cardiovascular events. We sought to determine the prognostic value of LAVI for predicting the outcome of patients who underwent dobutamine stress echocardiography (DSE) for known or suspected coronary artery disease (CAD). Methods From January 2000 to July 2005, we studied 981 patients who underwent DSE and off-line measurements of LAVI. The value of DSE over clinical and LAVI data was examined using a stepwise log-rank test. Results During a median follow-up of 24 months, 56 (6%) events occurred. By univariate analysis, predictors of events were male sex, diabetes mellitus, previous myocardial infarction, left ventricular ejection fraction (LVEF), left atrial diameter indexed, LAVI, and abnormal DSE. By multivariate analysis, independent predictors were LVEF (relative risk [RR] = 0.98, 95% CI 0.95-1.00), LAVI (RR = 1.04, 95% CI 1.02-1.05), and abnormal DSE (RR = 2.70, 95% CI 1.28-5.69). In an incremental multivariate model, LAVI was additional to clinical data for predicting events (chi(2) 36.8, P < .001). The addition of DSE to clinical and LAVI yielded incremental information (chi(2) 55.3, P < .001). The 3-year event-free survival in patients with normal DSE and LAVI <= 33 mL/m(2) was 96%; with abnormal DSE and LAVI <= 33 mL/m(2), 91%; with normal DSE and LAVI >34 mL/m(2), 83%; and with abnormal DSE and LAVI >34 mL/m(2) 51%. Conclusion Left atrial volume indexed provides independent prognostic information in patients who underwent DSE for known or suspected CAD. Among patients with normal DSE, those with larger LAVI had worse outcome, and among patients with abnormal DSE, LAVI was still predictive. (Am Heart J 2008; 156:1110-6.)

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In this study, we evaluated the biodistribution and the elimination kinetics of a biocompatible magnetic fluid, Endorem (TM), based on dextrancoated Fe(3)O(4) nanoparticles endovenously injected into Winstar rats. The iron content in blood and liver samples was recorded using electron paramagnetic resonance (EPR) and X-ray fluorescence (XRF) techniques. The EPR line intensity at g=2.1 was found to be proportional to the concentration of magnetic nanoparticles and the best temperature for spectra acquisition was 298 K. Both EPR and XRF analysis indicated that the maximum concentration of iron in the liver occurred 95 min after the ferrofluid administration. The half-life of the magnetic nanoparticles (MNP) in the blood was (11.6 +/- 0.6) min measured by EPR and (12.6 +/- 0.6) min determined by XRF. These results indicate that both EPR and XRF are very useful and appropriate techniques for the study of kinetics of ferrofluid elimination and biodistribution after its administration into the organism. (c) 2007 Elsevier B.V. All rights reserved.

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Background. The am of this study was to determine the predictive value for malignancy of microcalcifications determined by ultrasonography in thyroid nodules. Methods. One hundred seventy-seven nodules were prospectively studied by ultrasonography and compared with their fine-needle aspirative biopsy. The association between the presence and type of calcification and cytologic findings was verified through the chi-square test or likelihood ratio. Results. Thirty nodules showed calcification, of which 17 had fine calcifications, 3 had fine and gross calcifications, and 10 had only coarse calcification. Seven (41.18%) of 17 fine calcified nodules were malignant on cytology, 8 (47.06%) were benign, 1 (5,88%) was indeterminate, and 1 was suspect for malignancy. We found statistical significance between the presence of fine calcifications and malignancy (p =.001) and, in the 13 malignant nodule group, 8 (61.50%) had fine calcifications. Conclusion. This study suggests that microcalcifications were highly specific for malignancy and were present in 61% of the malignant nodules. (c) 2008 Wiley Periodicals, Inc.

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Background: Plantar fasciitis is the third most frequent injury in runners. Despite its high prevalence, its pathogenesis remains inconclusive. The literature reports overload as the basic mechanism for its development. However, the way that these plantar loads are distributed on the foot surface of runners with plantar fasciitis and the effects of pain on this mechanical factor has not yet been investigated. Therefore, the aim of this study was to evaluate and compare the plantar pressure distributions during running in runners with symptom or history of plantar fasciitis and runners without the disease. Methods: Forty-five recreational runners with plantar fasciitis (30 symptomatic and 15 with previous history of the disease) and 60 runners without plantar fasciitis (control group) were evaluated. Pain was assessed by a visual analogue scale. All runners were evaluated by means of the Pedar system insoles during running forty meters at a speed of 12(5%) km/h, using standard sport footwear. Two-way ANOVAS were employed to investigate the main and interaction effects between groups and plantar areas. Findings: No interaction effects were found for any of the investigated variables: peak pressure (P=0.61), contact area (P=0.38), contact time (P=0.91), and the pressure-time integral (P=0.50). Interpretation: These findings indicated that the patterns of plantar pressure distribution were not affected in recreational runners with plantar fasciitis when compared to control runners. Pain also did not interfere with the dynamic patterns of the plantar pressure distributions. (C) 2010 Elsevier Ltd. All rights reserved.

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The type of surface used for running can influence the load that the locomotor apparatus will absorb and the load distribution could be related to the incidence of chronic injuries. As there is no consensus on how the locomotor apparatus adapts to loads originating from running Surfaces with different compliance, the objective of this study was to investigate how loads are distributed over the plantar surface while running on natural grass and on a rigid surface-asphalt. Forty-four adult runners with 4 3 years of running experience were evaluated while running at 12 km/h for 40 m wearing standardised running shoes and Pedar insoles (Novel). Peak pressure, contact time and contact area were measured in six regions: lateral, central and medial rearfoot, midfoot, lateral and media] forefoot. The Surfaces and regions were compared by three ANOVAS (2 x 6). Asphalt and natural grass were statistically different in all variables. Higher peak pressures were observed on asphalt at the central (p < 0.001) [grass: 303.8(66.7) kPa; asphalt: 342.3(76.3) kPa] and lateral rearfoot (p < 0.001) [grass: 312.7(75.8) kPa: asphalt: 350.9(98.3) kPa] and lateral forefoot (p < 0.001) [grass: 221.5(42.9) kPa asphalt: 245.3(55.5) kPa]. For natural grass, contact time and contact area were significantly greater at the central rearfoot (p < 0.001). These results suggest that natural grass may be a Surface that provokes lighter loads on the rearfoot and forefoot in recreational runners. (C) 2008 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

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Hepatitis C virus (HCV) is a frequent cause of acute and chronic hepatitis and a leading cause for cirrhosis of the liver and hepatocellular carcinoma. HCV is classified in six major genotypes and more than 70 subtypes. In Colombian blood banks, serum samples were tested for anti-HCV antibodies using a third-generation ELISA. The aim of this study was to characterize the viral sequences in plasma of 184 volunteer blood donors who attended the ""Banco Nacional de Sangre de la Cruz Roja Colombiana,`` Bogota, Colombia. Three different HCV genomic regions were amplified by nested PCR. The first of these was a segment of 180 bp of the 5`UTR region to confirm the previous diagnosis by ELISA. From those that were positive to the 5`UTR region, two further segments were amplified for genotyping and subtyping by phylogenetic analysis: a segment of 380 bp from the NS5B region; and a segment of 391 bp from the E1 region. The distribution of HCV subtypes was: 1b (82.8%), 1a (5.7%), 2a (5.7%), 2b (2.8%), and 3a (2.8%). By applying Bayesian Markov chain Monte Carlo simulation, it was estimated that HCV-1b was introduced into Bogota around 1950. Also, this subtype spread at an exponential rate between about 1970 to about 1990, after which transmission of HCV was reduced by anti-HCV testing of this population. Among Colombian blood donors, HCV genotype 1b is the most frequent genotype, especially in large urban conglomerates such as Bogota, as is the case in other South American countries. J. Med. Virol. 82: 1889-1898, 2010. (C) 2010 Wiley-Liss, Inc.

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The aim of the present work was to assess the role of monocarboxylate transporters (MCTs), namely MCT1 and MCT4 as well as MCT/CD147 co-expression in gastric tissues and evaluate their clinico-pathological significance in gastric carcinoma. For that, we analysed the immunohistochemical expression of MCT1, MCT4 and CD147, in a large series of gastric samples, including non-neoplastic, tumour and metastatic tissues. A significant decrease in MCT4 plasma membrane expression was observed from non-neoplastic to gastric primary malignant tissues and to lymph-node metastasis and both MCT1 and MCT4 correlated with CD147. Importantly, both MCT4 and CD147 were more frequently expressed in Lauren`s intestinal-type tumours and MCT1/CD147 co-expression was associated with advanced gastric carcinoma, Lauren`s intestinal type, TNM staging and lymph-node metastasis. Our results showed that the prognostic value of CD147 was associated with MCTI co-expression in gastric cancer cells, supporting the view that CD147 plasma membrane activity is dependent on MCT co-expression. (C) 2009 Elsevier Ltd. All rights reserved.

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Background Standardization of total mesorectal excision (TME) had a great impact on decreasing local recurrence rates for the treatment of rectal cancer. However, exact numbers and distribution of lymph nodes (LN) along the mesorectum remains controversial with some studies suggesting that few LNs are present in the distal third of the mesorectum. Methods Eighteen fresh cadavers without a history of rectal cancer were studied. The rectum was removed by TME and then was divided into right lateral, posterior and left lateral sides, which were further subdivided into 3 levels (upper, middle and lower). A pathologist determined the number and sizes of the LNs in each of the nine areas, b linded to their anatomical origin. Results Overall, the mesorectum had a mean of 5.7 LNs (SD=3.7) and on average each LN had a maximum diameter of 3.0 mm (SD=2.7). There was no association between the mean number or size of LNs with gender, BMI, or age. There was a significantly higher prevalence of LNs in the posterior location (2.8 per mesorectum) than in the two lateral locations (0.8 and 1.2 per mesorectum; p=0.02). The distribution of LNs in the three levels of the rectum was not significant. Conclusions The distribution of LNs reinforces the fact that TME should always include the distal third of the mesorectum. Care must be taken to not violate the posterior aspect of the mesorectum.

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Information on hepatitis C virus (HCV) genotypic distribution among HIV-HCV co-infected patients is lacking in Brazil as well as other Latin American countries. The objective of this study was to evaluate the level of exposure to different risk factors associated with HCV transmission among a group of co-infected patients and to characterize the genotypic distribution of HCV in this cluster. A series of 100 HIV-HCV co-infected patients was analysed. The data to be analysed were collected from specific laboratory tests. Information was collected through a questionnaire. HCV genotyping was carried out by sequencing the 5 ` non-coding region of HCV. Chi-square and Fischer association tests or Kruskal-Wallis test were used to study the association between HCV transmission-related variables and the established genotypes. In conclusion, exposure to multiple risk factors associated with HCV transmission was common among HIV co-infected patients and an association between HCV genotype 3 and intravenous drug user was observed.