912 resultados para capability curve


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Objective: The purpose of this study was to investigate the reliability and validity of photogrammetry in measuring the lateral spinal inclination angles. Methods: Forty subjects (32 female and 8 males) with a mean age of 23.4 +/- 11.2 years had their scoliosis evaluated by radiographs of their trunk, determined by the Cobb angle method, and by photogrammetry. The statistical methods used included Cronbach alpha, Pearson/Spearman correlation coefficients, and regression analyses. Results: The Cronbach a values showed that the photogrammetric measures showed high internal consistency, which indicated that the sample was bias free. The radiograph method showed to be more precise with intrarater reliabilities of 0.936, 0.975, and 0.945 for the thoracic, lumbar, and thoracolumbar curves, respectively, and interrater reliabilities of 0.942 and 0.879 for the angular measures of the thoracic and thoracolumbar segments, respectively. The regression analyses revealed a high determination coefficient although limited to the adjusted linear model between the radiographic and photographic measures. It was found that with more severe scoliosis, the lateral curve measures obtained with the photogrammetry were for the thoracic and lumbar regions (R = 0.619 and 0.551). Conclusions: The photogrammetric measures were found to be reproducible in this study and could be used as Supplementary information to decrease the number of radiographs necessary for the monitoring of scoliosis. (J Manipulative Physiol Ther 2009;32:423-430)

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A flow cytometry-adapted fluorescent antibody to membrane antigen (FAMA) assay to detect IgG antibodies against varicella-zoster virus (VZV) was developed and tested in 62 serum samples, showing 90.32% accuracy obtained from a receiver operating characteristic (ROC) curve with a 0.9125 (95% confidence interval [CI], 0.829 to 1.00) area below the curve compared to the result with standard FAMA.

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Background The CAMCOG is a brief neuropsychological battery designed to assess global cognitive function and ascertain the impairments that are required for the diagnosis of dementia. To date, the cut-off scores for mild cognitive impairment (MCI) have not been determined. Given the need for an earlier diagnosis of mild dementia, new cut-off values are also necessary, taking into account cultural and educational effects. Methods One hundred and fifty-seven older adults (mean age: 69.6 +/- 7.4 years) with 8 or more years of formal education (mean years of schooling 14.2 +/- 3.8) attending a memory clinic at the Institute of Psychiatry University of Sao Paulo were included. Subjects were divided into three groups according to their cognitive status, established through clinical and neuropsychological assessment: normal controls, n = 62; MCI, n = 65; and mild or moderate dementia, n = 30. ROC curve analyses were performed for dementia vs controls, MCI vs controls and MCI vs dementia. Results The cut-off values were: 92/93 for dementia is controls (AUC = 0.99: sensitivity: 100%, specificity: 95%); 95/96 for MCI vs controls (AUC = 0.83, sensitivity: 64%, specificity: 88%), and 85/86 for MCI vs dementia (AUC = 0.91, sensitivity: 81%, specificity: 88%). The total CAMCOG score was more accurate than its subtests Mini-mental State Examination, Verbal Fluency Test and Clock Drawing Test when used separately. Conclusions The CAMCOG discriminated controls and MCI from demented patients, but was less accurate to discriminate MCI from controls. The best cut-off value to differentiate controls and demented was higher than suggested in the original publication, probably because only cases of mild to moderate dementia were included. This is important given the need for a diagnostic at earlier stages of Alzheimer`s disease. Copyright (C) 2008 John Wiley & Sons, Ltd.

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Diagnosis of autoimmune hepatitis (AIH) may be challenging. However, early diagnosis is important because immunosuppression is life-saving. Diagnostic criteria of the International Autoimmune Hepatitis Group (IAIHG) were complex and purely meant for scientific purposes. This study of the IAIHG aims to define simplified diagnostic criteria for routine clinical practice. Candidate criteria included sex, age, autoantibodies, immunoglobutins, absence of viral hepatitis, and histology. The training set included 250 AIH patients and 193 controls from 11 centers worldwide. Scores were built from variables showing predictive ability in univariate analysis. Diagnostic value of each score was assessed by the area under the receiver operating characteristic (ROC) curve. The best score was validated using data of an additional 109 AIH patients and 284 controls. This score included autoantibodies, immunoglobulin G, histology, and exclusion of viral hepatitis. The area under the curve for prediction of AIH was 0.946 in the training set and 0.91 in the validation set. Based on the ROC curves, two cutoff points were chosen. The score was found to have 88% sensitivity and 97% specificity (cutoff >= 6) and 81% sensitivity and 99% specificity (cutoff 2:7) in the validation set. Conclusion: A reliable diagnosis of AIH can be made using a very simple diagnostic score. We propose the diagnosis of probable AIH at a cutoff point greater than 6 points and definite AIH 7 points or higher.

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PURPOSE. To assess whether baseline Glaucoma Probability Score (GPS; HRT-3; Heidelberg Engineering, Dossenheim, Germany) results are predictive of progression in patients with suspected glaucoma. The GPS is a new feature of the confocal scanning laser ophthalmoscope that generates an operator-independent, three-dimensional model of the optic nerve head and gives a score for the probability that this model is consistent with glaucomatous damage. METHODS. The study included 223 patients with suspected glaucoma during an average follow-up of 63.3 months. Included subjects had a suspect optic disc appearance and/or elevated intraocular pressure, but normal visual fields. Conversion was defined as development of either repeatable abnormal visual fields or glaucomatous deterioration in the appearance of the optic disc during the study period. The association between baseline GPS and conversion was investigated by Cox regression models. RESULTS. Fifty-four (24.2%) eyes converted. In multivariate models, both higher values of GPS global and subjective stereophotograph assessment ( larger cup-disc ratio and glaucomatous grading) were predictive of conversion: adjusted hazard ratios (95% CI): 1.31 (1.15 - 1.50) per 0.1 higher global GPS, 1.34 (1.12 - 1.62) per 0.1 higher CDR, and 2.34 (1.22 - 4.47) for abnormal grading, respectively. No significant differences ( P > 0.05 for all comparisons) were found between the c-index values ( equivalent to area under ROC curve) for the multivariate models (0.732, 0.705, and 0.699, respectively). CONCLUSIONS. GPS values were predictive of conversion in our population of patients with suspected glaucoma. Further, they performed as well as subjective assessment of the optic disc. These results suggest that GPS could potentially replace stereophotograph as a tool for estimating the likelihood of conversion to glaucoma.

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We investigated the effects of the antioxidant N-acetylcysteine (NAC) on early outcomes of deceased donor renal transplantation. Between April 2005 and June 2008, adult primary graft recipients of deceased renal donors were assigned to treatment (n = 38) or control (n = 36) groups and evaluated for 90 days and one year after renal transplantation. The treatment group received NAC orally (600 mg twice daily) from day 0 to 7 postoperatively. Renal function was determined by serum creatinine, MDRD and Cockcroft-Gault estimated GFR (eGFR), delayed graft function (DGF) and dialysis free Kaplan-Meier estimate curve. Serum levels of thiobarbituric acid reactive substances (TBARS), were employed as markers of oxidative stress. The NAC group displayed a lower mean serum creatinine during the first 90 days (P = .026) and at 1 year after transplantation (P = .005). Furthermore, the NAC group showed a higher mean eGFR throughout the first 90 days and at 1 year. DGF was lower among the NAC group (P = .017) and these recipients required fewer days of dialysis (P = .012). Oxidative stress was significantly attenuated with NAC (P < .001). Our results suggested that NAC enhanced early outcomes of deceased donor renal transplantation by attenuating oxidative stress.

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Objectives: The link between obesity and endogenous estrogen with coronary artery disease (CAD) in postmenopausal women is uncertain. In this prospective study we analyzed the association of body mass index (BMI) and blood levels of estrone in postmenopausal women with known CAD or with a high risk factor score for CAD. Methods: Participants were 251 female clinic patients aged 50-90 years who were postmenopausal and not using estrogen therapy. Clinical and behavioral characteristics and fasting blood for estrone and heart disease risk factors were collected at baseline, and again at I and 2 years. Women were grouped according to their BMI (kg/m(2)) as normal (18.5 <= BMI < 25), overweight (25 <= BMI < 30) or obese (BMI >= 30), and by low and high estrone levels (< 15 and >= 15 pg/mL, respectively). Fatal and nonfatal events were recorded for 2 years after baseline. Results: Women with a low estrone level were older, thinner, and had less hypertension, diabetes, and lower triglyceride and glucose levels. BMI was positively associated with estrone levels, hypertension, and diabetes and inversely associated with HDL cholesterol. There were 14 deaths, 8 attributed to CAD. The Kaplan-Meier survival curve showed a nonsignificant trend (p = 0.074) of greater all cause mortality in women with low estrone levels (< 15 mL). In this model, adjusted for BMI, age [OR 1.08; p = 0.03], C-reactive protein [OR = 1.24; p = 0.024] and hypertension [OR = 6.22; p = 0.003] were independent predictors of all cause mortality. Conclusions: Postmenopausal women with low estrone levels (< 15 pg/mL) had a trend for increased mortality over the next 2 years. Larger, longer studies are needed. (c) 2008 Elsevier Ireland Ltd. All rights reserved.

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Objective: To develop a model to predict the bleeding source and identify the cohort amongst patients with acute gastrointestinal bleeding (GIB) who require urgent intervention, including endoscopy. Patients with acute GIB, an unpredictable event, are most commonly evaluated and managed by non-gastroenterologists. Rapid and consistently reliable risk stratification of patients with acute GIB for urgent endoscopy may potentially improve outcomes amongst such patients by targeting scarce health-care resources to those who need it the most. Design and methods: Using ICD-9 codes for acute GIB, 189 patients with acute GIB and all. available data variables required to develop and test models were identified from a hospital medical records database. Data on 122 patients was utilized for development of the model and on 67 patients utilized to perform comparative analysis of the models. Clinical data such as presenting signs and symptoms, demographic data, presence of co-morbidities, laboratory data and corresponding endoscopic diagnosis and outcomes were collected. Clinical data and endoscopic diagnosis collected for each patient was utilized to retrospectively ascertain optimal management for each patient. Clinical presentations and corresponding treatment was utilized as training examples. Eight mathematical models including artificial neural network (ANN), support vector machine (SVM), k-nearest neighbor, linear discriminant analysis (LDA), shrunken centroid (SC), random forest (RF), logistic regression, and boosting were trained and tested. The performance of these models was compared using standard statistical analysis and ROC curves. Results: Overall the random forest model best predicted the source, need for resuscitation, and disposition with accuracies of approximately 80% or higher (accuracy for endoscopy was greater than 75%). The area under ROC curve for RF was greater than 0.85, indicating excellent performance by the random forest model Conclusion: While most mathematical models are effective as a decision support system for evaluation and management of patients with acute GIB, in our testing, the RF model consistently demonstrated the best performance. Amongst patients presenting with acute GIB, mathematical models may facilitate the identification of the source of GIB, need for intervention and allow optimization of care and healthcare resource allocation; these however require further validation. (c) 2007 Elsevier B.V. All rights reserved.

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This study was designed to examine the use of the QuantiFERON-TB Gold assay as an aid in the diagnosis of active pulmonary tuberculosis (TB) in Brazilian patients. Using the receiver operating characteristic curve, the cutoff was adjusted to >= 0.20 IU/ml. The sensitivity increased to 86%, with 100% specificity. All TB patients with negative sputum smear microscopy and negative culture results were positive using this test.

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Study Design. Prospective clinical electromyographic study in adolescents with idiopathic scoliosis and control group. Objective. To evaluate electromyographic amplitude from erector spinae muscles of patients with idiopathic scoliosis in comparison with control volunteers without spinal deformities. Summary of Background Data. Previous studies have indicated an increased electromyographic activity in paravertebral muscles in the convex side of the scoliotic curvature. However, in previous studies there is the absence or poor description of methods used, and some studies were conducted before the recording and processing recommendations for surface electromyographic signals had been described. Methods. Thirty individuals, matched by sex, age, and body mass index, were divided into two groups: scoliosis and control. The electric activity of the erector spinae muscles was determined by surface electromyography on both sides of the three levels of spine: T8, L2, and L5. Results. Normalized electromyographic amplitudes of erector spinae muscles, in the convex and concave sides of the apex region of the scoliotic curve in the thoracic and lumbar regions, were not significantly different. Also, there was no significant difference between the muscles of these regions when the scoliosis group was compared with the control group. The erector spinae muscle at the L5 level, representing the lower vertebral limit of the lumbar scoliotic curve, had significantly higher electromyographic activity on the convex side. However, the same alteration was shown in the control group homologous muscle (on the left side). Conclusion. Erector spinae muscles on the convex and concave sides at the curvature apex in patients with idiopathic scoliosis and small magnitude of curves did not show significant differences in electromyographic amplitude. Future studies should evaluate whether intragroup activation differences, at the L5 level in 80% of the maximum voluntary isometric contractions with predominance of the left side of the vertebral column, have any relation to the condition.

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The transition from marine/brackish waters to freshwater habitats constitutes a severe osmotic and ionic challenge, and successful invasion has demanded the selection of morphological, physiological, biochemical and behavioral adaptations. We evaluated short-term (1 to 12 h exposure) and long-term (5 d acclimation), anisosmotic extracellular (osmolality, [Na(+), Cl(-)]) and long-term isosmotic intracellular osmoregulatory capability in Palaemon northropi, a neotropical intertidal shrimp. F northropi survives well and osmo- and ionoregulates strongly during short- and long-term exposure to 5-45 parts per thousand salinity, consistent with its rocky tide pool habitat subject to cyclic salinity fluctuations, Muscle total free amino acid (FAA) concentrations decreased by 63% in shrimp acclimated to 5%. salinity, revealing a role in hypoosmotic cell volume regulation; this decrease is mainly a consequence of diminished glycine, arginine and proline. Total FAA contributed 31% to muscle intracellular osmolality at 20 parts per thousand, an isosmotic salinity, and decreased to 13% after acclimation to 5 parts per thousand. Gill and nerve tissue FAA concentrations remained unaltered. These tissue-specific responses reflect efficient anisosmotic and anisoionic extracellular regulatory mechanisms, and reveal the dependence of muscle tissue on intracellular osmotic effectors. FAA concentration is higher in P. northropi than in diadromous and hololimnetic palaemonids, confirming muscle FAA concentration as a good parameter to evaluate the degree of adaptation to dilute media. The osmoregulatory capability of P. northropi may reflect the potential physiological capacity of ancestral marine palaemonids to penetrate into dilute media, and reveals the importance of evaluating osmoregulatory processes in endeavors to comprehend the invasion of dilute media by ancestral marine crustaceans.

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The protozoan parasite Leishmania presents a dynamic and plastic genome in which gene amplification and chromosome translocations are common phenomena. Such plasticity hints at the necessity of dependable genome maintenance pathways. Eukaryotic cells have evolved checkpoint control systems that recognize altered DNA structures and halt cell cycle progression allowing DNA repair to take place. In these cells, the PCNA-related heterotrimeric complex formed by the proteins Hus1, Rad9, and Rad1 is known to participate in the early steps of replicative stress sensing and signaling. Here we show that the Hus1 homolog of Leishmania major is a nuclear protein that improves the cell capability to cope with replicative stress. Overexpression of LmHus1 confers resistance to the genotoxic drugs hydroxyurea (HU) and methyl methanesulfonate (MMS) and resistance to HU correlates to reduced net DNA damage upon LmHus1 expression. (C) 2011 Elsevier B.V. All rights reserved.