Enhancement of diagnostic efficiency by a gamma interferon release assay for pulmonary tuberculosis

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.

Right adolescent idiopathic thoracic curve (Lenke 1 A and B): does cost of instrumentation and implant density improve radiographic and cosmetic parameters?

In adolescent idiopathic scoliosis (AIS) there has been a shift towards increasing the number of implants and pedicle screws, which has not been proven to improve cosmetic correction. To evaluate if increasing cost of instrumentation correlates with cosmetic correction using clinical photographs. 58 Lenke 1A and B cases from a multicenter AIS database with at least 3 months follow-up of clinical photographs were used for analysis. Cosmetic parameters on PA and forward bending photographs included angular measurements of trunk shift, shoulder balance, rib hump, and ratio measurements of waist line asymmetry. Pre-op and follow-up X-rays were measured for coronal and sagittal deformity parameters. Cost density was calculated by dividing the total cost of instrumentation by the number of vertebrae being fused. Linear regression and spearman`s correlation were used to correlate cost density to X-ray and photo outcomes. Three independent observers verified radiographic and cosmetic parameters for inter/interobserver variability analysis. Average pre-op Cobb angle and instrumented correction were 54A degrees (SD 12.5) and 59% (SD 25) respectively. The average number of vertebrae fused was 10 (SD 1.9). The total cost of spinal instrumentation ranged from $6,769 to $21,274 (Mean $12,662, SD $3,858). There was a weak positive and statistically significant correlation between Cobb angle correction and cost density (r = 0.33, p = 0.01), and no correlation between Cobb angle correction of the uninstrumented lumbar spine and cost density (r = 0.15, p = 0.26). There was no significant correlation between all sagittal X-ray measurements or any of the photo parameters and cost density. There was good to excellent inter/intraobserver variability of all photographic parameters based on the intraclass correlation coefficient (ICC 0.74-0.98). Our method used to measure cosmesis had good to excellent inter/intraobserver variability, and may be an effective tool to objectively assess cosmesis from photographs. Since increasing cost density only improves mildly the Cobb angle correction of the main thoracic curve and not the correction of the uninstrumented spine or any of the cosmetic parameters, one should consider the cost of increasing implant density in Lenke 1A and B curves. In the area of rationalization of health care expenses, this study demonstrates that increasing the number of implants does not improve any relevant cosmetic or radiographic outcomes.

An association rule-based method to support medical image diagnosis with efficiency

In this paper, we propose a method based on association rule-mining to enhance the diagnosis of medical images (mammograms). It combines low-level features automatically extracted from images and high-level knowledge from specialists to search for patterns. Our method analyzes medical images and automatically generates suggestions of diagnoses employing mining of association rules. The suggestions of diagnosis are used to accelerate the image analysis performed by specialists as well as to provide them an alternative to work on. The proposed method uses two new algorithms, PreSAGe and HiCARe. The PreSAGe algorithm combines, in a single step, feature selection and discretization, and reduces the mining complexity. Experiments performed on PreSAGe show that this algorithm is highly suitable to perform feature selection and discretization in medical images. HiCARe is a new associative classifier. The HiCARe algorithm has an important property that makes it unique: it assigns multiple keywords per image to suggest a diagnosis with high values of accuracy. Our method was applied to real datasets, and the results show high sensitivity (up to 95%) and accuracy (up to 92%), allowing us to claim that the use of association rules is a powerful means to assist in the diagnosing task.

Arteriovenous Fistula Puncture: An Essential Factor for Hemodialysis Efficiency

Objective. To determine the blood recirculation ratio in the vascular access of patients on hemodialysis, and to calculate the Kt/Vs obtained with the different techniques of arteriovenous fistula punctures. Materials and Methods. A total of 174 patients were divided according to the technique used for arteriovenous fistula puncture: group 1, needles in opposite directions and with a distance of 5 cm or more between them; group 2, needles in opposite directions but with a distance of less than 5 cm; group 3, unidirectional needles with both directed to the heart and with a distance of 5 cm or more; group 4, unidirectional needles but separated by a distance of less than 5 cm between needles; and group 5, patients carrying a temporary venous catheter. Blood samples were collected for urea analysis, pre and post-dialysis for Kt/V rate, and other samples for calculation of the access recirculation. Results. Group 1 presented the lowest rate of access recirculation (8.51 +/- 4.90%) and the best Kt/V (1.71 +/- 0.36), while group 4 presented the worst access recirculation (20.68 +/- 4.92%) and Kt/V (1.16 +/- 0.26). All groups differed significantly from group 4 (p < 0.05), except group 5 with regard for Kt/V parameter. Discussion. The technique of arteriovenous fistula puncture is an essential factor to decrease the access recirculation and assure better results of measurement of hemodialysis adequacy. On the basis of the results obtained, insertion of the needles in the same direction and with a distance of less than 5 cm between them should be avoided.

Efficiency of the DNA repair and polymorphisms of the XRCC1, XRCC3 and XRCC4 DNA repair genes in systemic lupus erythematosus

Impaired DNA repair efficiency in systematic lupus erythematosus (SLE) patients has been reported ill some studies, mainly regarding the repair of oxidative damage, but little is known about repair kinetics towards primarily single-stranded DNA breaks. In the present study, we aimed to investigate: (a) the efficiency of SLE peripheral blood leucocytes in repairing DNA damage induced by ionizing radiation and (b) the association of DNA repair gene (XRCC1 Arg399Gln, XRCC3 Thr241Met and XRCC4 Ile401Thr) polymorphisms in SLE patients, considering the whole group, or stratified sub-groups according to clinical and laboratory features. A total of 163 SLE patients and 125 healthy control were studied. The kinetics of DNA strand break repair was evaluated by the comet assay, and genotyping for DNA repair genes was performed by PCR-RFLP. Compared with controls. SLE leucocytes exhibited decreased efficiency of DNA repair evaluated at 30 min following irradiation. A significant association with DNA repair gene polymorphisms was not observed for the whole group of SLE patients; however, the XRCC1Arg399Gln polymorphism was associated with the presence of anti-dsDNA antibody. The concomitance of two DNA repair polymorphic sites was associated with the presence of neuropsychiatric manifestations and antiphospholipid antibody syndrome. Taken together, these results indicated that SLE leucocytes repair less efficiently the radiation-induced DNA damage, and DNA repair polymorphic sites may predispose to the development of particular clinical and laboratory features. Lupus (2008) 17, 988-995.

Detection of Clonal Immunoglobulin and T-Cell Receptor Gene Rearrangements in Childhood Acute Lymphoblastic Leukemia Using a Low-Cost PCR Strategy

Background Imunoglobulin (Ig) and T cell receptor (TCR) gene rearrangements function as specific markers for minimal residual disease (MRD) which is one of the best predictors of outcome in childhood acute lymphoblastic leukemia (ALL) We recently reported on the prognostic value of MRD during the induction of remission through a simplified PCR method Here we report on gene rearrangement frequencies and offer guidelines for the application of the technique Procedure Two hundred thirty three children had DNA extracted from bone marrow Ig and TCR gene rearrangements were amplified using consensus primers and conventional PCR PCR products were submitted to homo/heteroduplex analysis A computer program was designed to define combinations of targets for clonal detection using a minimum set of primers and reactions Results At least one clonal marker could be detected in 98% of the patients and two markers in approximately 80% The most commonly rear ringed genes in precursor B cell ALL were IgH (75%) TCRD (59%) IgK (55%), and TCRG (54%) The most commonly rearranged genes for TALL were TCRG (100%) and TCRD (24%) The sensitivity of primers was limited to the detection of 1 leukemic cell among 100 normal cells Conclusions We propose that eight PCR reactions per ALL subtype would allow for the detection of two markers in most cases In addition these reactions ire suitable for MRD monitoring especially when aiming the selection of patients with high MRD levels (>= 10(-2)) at the end of induction therapy Such an approach would be very useful in centers with limited financial resources Pediatr Blood Cancer 2010 55 1278-1286 (C) 2010 Wiley Liss Inc

Cost-effectiveness analysis of universal childhood vaccination against varicella in Brazil

This study conducts a cost-effectiveness analysis of a childhood universal varicella vaccination program in Brazil. An age and time-dependent dynamic model was developed to estimate the incidence of varicella for 30 years. Assuming a single-dose schedule; vaccine efficacy of 85% and coverage of 80%, the program could prevent 74,422,058 cases and 2905 deaths. It would cost R$ 3,178,396,110 and save R$ 660,076,410 to the society and R$ 365,602,305 to the healthcare system. The program is cost-effective (R$ 14,749 and R$ 16,582 per life-year saved under the societal and the healthcare system`s perspective, respectively). The program`s cost-effectiveness is highly sensitive to the vaccine price and number of doses. (C) 2008 Elsevier Ltd. All rights reserved.

Comparative efficiency of Class II malocclusion treatment with the pendulum appliance or two maxillary premolar extractions and edgewire appliances

The objective of this study was to compare, on study models and initial cephalograms, the efficiency of Class II malocclusion treatment with the pendulum appliance, and with two maxillary premolar extraction protocol. The sample consisted of 48 treated Class II malocclusion patients: group 1 comprised 22 patients (7 males, 15 females) treated with the pendulum appliance, with an initial mean age of 14.44 years and group 2, 26 patients (14 males, 12 females) treated with two maxillary premolar extractions at an initial mean age of 13.66 years. To compare the efficiency of each treatment protocol, the occlusal outcomes were evaluated on dental casts using the Peer Assessment Rating (PAR) Index and the treatment time (TT) of each group was calculated on clinical charts. The degree of treatment efficiency was calculated as the ratio between the percentage of occlusal improvement, evaluated through the PAR index, and TT. Statistical analysis was undertaken by means of t-tests. The findings demonstrated that the two maxillary premolar extraction protocol provided the occlusal outcomes in a shorter time (group 1: 45.7 months, group 2: 23.01 months) and, therefore, demonstrated greater treatment efficiency than the pendulum appliance.

Occlusal outcomes and efficiency of 1-and 2-phase protocols in the treatment of Class II Division 1 malocclusion

Introduction: The purpose of this study was to compare the occlusal outcomes and the efficiency of 1-phase and 2-phase treatment protocols in Class II Division 1 malocclusions. Treatment efficiency was defined as a change in the occlusal characteristics in a shorter treatment time. Methods: Class II Division 1 subjects ( n = 139) were divided into 2 groups according to the treatment protocol for Class II correction. Group 1 comprised 78 patients treated with a 1-phase treatment protocol at initial and final mean ages of 12.51 and 14.68 years. Group 2 comprised 61 patients treated with a 2-phase treatment protocol at initial and final mean ages of 11.21 and 14.70 years. Lateral cephalometric radiographs were taken at the pretreatment stage to evaluate morphological differences in the groups. The initial and final study models of the patients were evaluated by using the peer assessment rating index. Chi-square tests were used to test for differences between the 2 groups for categorical variables. Variables regarding occlusal results were compared by using independent t tests. A linear regression analysis was completed, with total treatment time as the dependent variable, to identify clinical factors that predict treatment length for patients with Class II malocclusions. Results: Similar occlusal outcomes were obtained between the 1-phase and the 2-phase treatment protocols, but the duration of treatment was significantly shorter in the 1-phase treatment protocol group. Conclusions: Treatment of Class II Division 1 malocclusions is more efficient with the 1-phase than the 2-phase treatment protocol.