316 resultados para Randomized Algorithms


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We tested the efficacy and safety of different combination therapies in hypertensive patients with uncontrolled blood pressure (BP) on a monotherapy with a calcium antagonist: 1,647 hypertensive patients were enrolled to receive placebo for 4 weeks followed by isradipine (ISR) 2.5 mg twice daily (b.i.d.) for 4 weeks. Nonresponders [diastolic BP (DBP) > 90 mm Hg] were randomly assigned to receive either the beta-blocker bopindolol 0.5 or 1 mg/day, the diuretic metolazone 1.25 or 2.5 mg/day, the angiotensin-converting enzyme (ACE) inhibitor enalapril 10 or 20 mg/day, ISR 5 mg b.i.d., or placebo. One hundred seventy-five receiving placebo dropped out; 93% (n = 1,376) of the 1,472 patients finished 4-week monotherapy with ISR. Sixty percent (n = 826) reached target BP, and 40% (n = 550) remained uncontrolled and were randomized. Regardless of dosage, all drugs led to a comparable reduction in BP except for the lower dosage of bopindolol and ISR 5 mg b.i.d., which were less effective in lowering systolic BP (SBP). The BP decrease achieved by combination therapy ranged from 10 to 15 mm Hg SBP and from 7 to 11 mm Hg DBP but remained unchanged with placebo. Side effects were minor, and only 2.4% of patients discontinued therapy because of side effects. The side-effect score for edema was lower with ISR plus diuretics than with other combinations, whereas the ACE inhibitor was associated with a higher score for cough. Monotherapy with a calcium antagonist normalizes BP in about two-thirds of patients when used in general practice.(ABSTRACT TRUNCATED AT 250 WORDS)

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Purpose: To compare the long-term outcome of treatment with concomitant cisplatin and hyperfractionated radiotherapy versus treatment with hyperfractionated radiotherapy alone in patients with locally advanced head and neck cancer.Methods and Materials: From July 1994 to July 2000, a total of 224 patients with squamous cell carcinoma of the head and neck were randomized to receive either hyperfractionated radiotherapy alone (median total dose, 74.4 Gy; 1.2 Gy twice daily; 5 days per week) or the same radiotherapy combined with two cycles of cisplatin (20 mg/m(2) for 5 consecutive days during weeks 1 and 5). The primary endpoint was the time to any treatment failure; secondary endpoints were locoregional failure, metastatic failure, overall survival, and late toxicity assessed according to Radiation Therapy Oncology Group criteria.Results: Median follow-up was 9.5 years (range, 0.1-15.4 years). Median time to any treatment failure was not significantly different between treatment arms (hazard ratio [HR], 1.2 [95% confidence interval [CM 0.9-1.7; p = 0.17]). Rates of locoregional failure-free survival (HR, 1.5 [95% CI, 1.1-2.1;p = 0.021), distant metastasis-free survival (HR, 1.6 [95% CI, 1.1-2.5; p = 0.021), and cancer-specific survival (HR, 1.6 [95% CI, 1.0-2.5;p = 0.03]) were significantly improved in the combined-treatment arm, with no difference in major late toxicity between treatment arms. However, overall survival was not significantly different (HR, 1.3 [95% CI, 0.9-1.8; p = 0.11]).Conclusions: After long-term follow-up, combined-treatment with cisplatin and hyperfractionated radiotherapy maintained improved rates of locoregional control, distant metastasis-free survival, and cancer-specific survival compared to that of hyperfractionated radiotherapy alone, with no difference in major late toxicity. (C) 2012 Elsevier Inc.

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BACKGROUND: Surgical site infection after stoma reversal is common. The optimal skin closure technique after stoma reversal has been widely debated in the literature. OBJECTIVE: We hypothesized that pursestring near-complete closure of the stoma site would lead to fewer surgical site infections compared with conventional primary closure. DESIGN: This study was a parallel prospective multicenter randomized controlled trial. SETTINGS: This study was conducted at 2 university medical centers. PATIENTS: Patients (N = 122) presenting for elective colostomy or ileostomy reversal were selected. INTERVENTIONS: Pursestring versus conventional primary closure of stoma sites were compared. MAIN OUTCOME MEASURES: Stoma site surgical site infection within 30 days of surgery, overall surgical site infection, delayed healing (open wound for >30 days), time to wound epithelialization, and patient satisfaction were the primary outcomes measured. RESULTS: The pursestring group had a significantly lower stoma site infection rate (2% vs 15%, p = 0.01). There was no difference in delayed healing or patient satisfaction between groups. Time to epithelialization was measured in only 51 patients but was significantly longer in the pursestring group (34.6 ± 20 days vs 24.1 ± 17 days, p = 0.02). LIMITATIONS: This study was limited by the variability in procedures and surgeons, the limited follow-up after 30 days, and the inability to perform blinding. CONCLUSION: Pursestring closure after stoma reversal has a lower risk of stoma site surgical site infection than conventional primary closure, although wounds may take longer to heal with the use of this approach. REGISTRATION NUMBER: NCT01713452 (www.clinicaltrials.gov).

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This paper presents general problems and approaches for the spatial data analysis using machine learning algorithms. Machine learning is a very powerful approach to adaptive data analysis, modelling and visualisation. The key feature of the machine learning algorithms is that they learn from empirical data and can be used in cases when the modelled environmental phenomena are hidden, nonlinear, noisy and highly variable in space and in time. Most of the machines learning algorithms are universal and adaptive modelling tools developed to solve basic problems of learning from data: classification/pattern recognition, regression/mapping and probability density modelling. In the present report some of the widely used machine learning algorithms, namely artificial neural networks (ANN) of different architectures and Support Vector Machines (SVM), are adapted to the problems of the analysis and modelling of geo-spatial data. Machine learning algorithms have an important advantage over traditional models of spatial statistics when problems are considered in a high dimensional geo-feature spaces, when the dimension of space exceeds 5. Such features are usually generated, for example, from digital elevation models, remote sensing images, etc. An important extension of models concerns considering of real space constrains like geomorphology, networks, and other natural structures. Recent developments in semi-supervised learning can improve modelling of environmental phenomena taking into account on geo-manifolds. An important part of the study deals with the analysis of relevant variables and models' inputs. This problem is approached by using different feature selection/feature extraction nonlinear tools. To demonstrate the application of machine learning algorithms several interesting case studies are considered: digital soil mapping using SVM, automatic mapping of soil and water system pollution using ANN; natural hazards risk analysis (avalanches, landslides), assessments of renewable resources (wind fields) with SVM and ANN models, etc. The dimensionality of spaces considered varies from 2 to more than 30. Figures 1, 2, 3 demonstrate some results of the studies and their outputs. Finally, the results of environmental mapping are discussed and compared with traditional models of geostatistics.

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Purpose: To evaluate the extent of quality of life (QoL) associated adverse events (AEs) following PRECISION TACE with DC Bead compared with conventional transarterial chemoembolisation (cTACE). Methods and Materials: 201 intermediate HCC patients were treated with DC Bead (PRECISION TACE) or conventional TACE (cTACE) with doxorubicin in the PRECISION V clinical study. 93 patients were treated with DC Bead and 108 Patients with cTACE every 2 months and followed up for 6 months. AEs were classified according to the South West Oncology Group criteria. QoL associated AEs were defined as alopecia, constipation, nausea, vomiting, pyrexia, chills, asthenia, fatigue, and headache. Results: The biggest difference in QoL associated AEs was for alopecia: 2 patients (2.2%) for DC-Bead versus 21 patients (19.4%) for cTACE. For other clinical symptoms, constipation (n=10; 10.8% vs. n=13; 12%), vomiting (n=10; 10.8% vs. n=14; 13.0%), pyrexia (n=16; 17.2% vs. n=26; 24.1%), chills (n=1; 1.1% vs. n=5; 4.6%), and headache (n=2; 2.2% vs. n=8; 7.4%) showed lower incidence in the DC Bead group versus cTACE. Nausea, n= 15; 13.9% (n=15; 16.1%) and fatigue, n=6; 5.6% (n=13; 14.0%) were lower for cTACE. Total dose of doxorubicin was on average 35% higher in the DC Bead group. Conclusion: Although patients in the DC Bead group received a higher doxorubicin dose, less QoL associated AEs were reported for this group. Alopecia, the most obvious outward sign of toxicity, was only reported in a tenth of DC Bead patients. Thus, PRECISION TACE with DC Bead improves quality of life associated adverse events.

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BACKGROUND: Recent clinical recommendations still propose active exercises (AE) for CNSLBP. However, acceptance of exercises by patients may be limited by pain-related manifestations. Current evidences suggest that manual therapy (MT) induces an immediate analgesic effect through neurophysiologic mechanisms at peripheral, spinal and cortical levels. The aim of this pilot study was first, to assess whether MT has an immediate analgesic effect, and second, to compare the lasting effect on functional disability of MT plus AE to sham therapy (ST) plus AE. METHODS: Forty-two CNSLBP patients without co-morbidities, randomly distributed into 2 treatment groups, received either spinal manipulation/mobilization (first intervention) plus AE (MT group; n = 22), or detuned ultrasound (first intervention) plus AE (ST group; n = 20). Eight therapeutic sessions were delivered over 4 to 8 weeks. Immediate analgesic effect was obtained by measuring pain intensity (Visual Analogue Scale) before and immediately after the first intervention of each therapeutic session. Pain intensity, disability (Oswestry Disability Index), fear-avoidance beliefs (Fear-Avoidance Beliefs Questionnaire), erector spinae and abdominal muscles endurance (Sorensen and Shirado tests) were assessed before treatment, after the 8th therapeutic session, and at 3- and 6-month follow-ups. RESULTS: Thirty-seven subjects completed the study. MT intervention induced a better immediate analgesic effect that was independent from the therapeutic session (VAS mean difference between interventions: -0.8; 95% CI: -1.2 to -0.3). Independently from time after treatment, MT + AE induced lower disability (ODI mean group difference: -7.1; 95% CI: -12.8 to -1.5) and a trend to lower pain (VAS mean group difference: -1.2; 95% CI: -2.4 to -0.30). Six months after treatment, Shirado test was better for the ST group (Shirado mean group difference: -61.6; 95% CI: -117.5 to -5.7). Insufficient evidence for group differences was found in remaining outcomes. CONCLUSIONS: This study confirmed the immediate analgesic effect of MT over ST. Followed by specific active exercises, it reduces significantly functional disability and tends to induce a larger decrease in pain intensity, compared to a control group. These results confirm the clinical relevance of MT as an appropriate treatment for CNSLBP. Its neurophysiologic mechanisms at cortical level should be investigated more thoroughly. TRIAL REGISTRATION: Trial registration number: NCT01496144.

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BACKGROUND: Chronic lung allograft dysfunction, which manifests as bronchiolitis obliterans syndrome (BOS), is recognized as the primary cause of morbidity and mortality after lung transplantation. In this study we assessed the efficacy and safety of two de novo immunosuppression protocols to prevent BOS. METHODS: Our study approach was a multicenter, prospective, randomized (1:1) open-label superiority investigation of de novo tacrolimus vs cyclosporine, with both study arms given mycophenolate mofetil and prednisolone after lung transplantation. Cytolytic induction therapy was not employed. Patients were stratified at entry for cystic fibrosis. Primary outcome was incidence of BOS 3 years after transplant (intention-to-treat analysis). Secondary outcomes were survival and incidence of acute rejection, infection and other adverse events. RESULTS: Group demographic data were well matched: 110 of 124 tacrolimus vs 74 of 125 cyclosporine patients were treated per protocol (p < 0.01 by chi-square test). Cumulative incidence of BOS Grade ≥1 at 3 years was 11.6% (tacrolimus) vs 21.3% (cyclosporine) (cumulative incidence curves, p = 0.037 by Gray's test, pooled over strata). Univariate proportional sub-distribution hazards regression confirmed cyclosporine as a risk for BOS (HR 1.97, 95% CI 1.04 to 3.77, p = 0.039). Three-year cumulative incidence of acute rejection was 67.4% (tacrolimus) vs 74.9% (cyclosporine) (p = 0.118 by Gray's test). One- and 3-year survival rates were 84.6% and 78.7% (tacrolimus) vs 88.6% and 82.8% (cyclosporine) (p = 0.382 by log-rank test). Cumulative infection rates were similar (p = 0.91), but there was a trend toward new-onset renal failure with tacrolimus (p = 0.09). CONCLUSIONS: Compared with cyclosporine, de novo tacrolimus use was found to be associated with a significantly reduced risk for BOS Grade ≥1 at 3 years despite a similar rate of acute rejection. However, no survival advantage was detected.

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BACKGROUND: In uveal melanoma (UM) with metastatic disease limited to the liver, the effect of an intrahepatic treatment on survival is unknown. We investigated prospectively the efficacy and toxicity of hepatic intra-arterial (HIA) versus systemic (IV) fotemustine in patients with liver metastases from UM. PATIENTS AND METHODS: Patients were randomly assigned to receive either IV or HIA fotemustine at 100 mg/m(2) on days 1, 8, 15 (and 22 in HIA arm only) as induction, and after a 5-week rest period every 3 weeks as maintenance. Primary end point was overall survival (OS). Response rate (RR), progression-free survival (PFS) and safety were secondary end points. RESULTS: Accrual was stopped after randomization of 171 patients based on the results of a futility OS analysis. A total of 155 patients died and 16 were still alive [median follow-up 1.6 years (range 0.25-6 years)]. HIA did not improve OS (median 14.6 months) when compared with the IV arm (median 13.8 months), hazard ratio (HR) 1.09; 95% confidence interval (CI) 0.79-1.50, log-rank P = 0.59. However, there was a significant benefit on PFS for HIA compared with IV with a median of 4.5 versus 3.5 months, respectively (HR 0.62; 95% CI 0.45-0.84, log-rank P = 0.002). The 1-year PFS rate was 24% in the HIA arm versus 8% in the IV arm. An improved RR was seen in the HIA (10.5%) compared with IV treatment (2.4%). In the IV arm, the most frequent grade ≥3 toxicity was thrombocytopenia (42.1%) and neutropenia (62.6%), compared with 21.2% and 28.7% in the HIA arm. The main grade ≥3 toxicity related to HIA was catheter complications (12%) and liver toxicity (4.5%) apart from two toxic deaths. CONCLUSION: HIA treatment with fotemustine did not translate into an improved OS compared with IV treatment, despite better RR and PFS. Intrahepatic treatment should still be considered as experimental. EUDRACT NUMBER AND CLINICALTRIALSGOV IDENTIFIER: 2004-002245-12 and NCT00110123.

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OBJECTIVE The risk of carrying methicillin-resistant Staphylococcus aureus (MRSA) is higher among nursing home (NH) residents than in the general population. However, control strategies are not clearly defined in this setting. In this study, we compared the impact of standard precautions either alone (control) or combined with screening of residents and decolonization of carriers (intervention) to control MRSA in NHs. DESIGN Cluster randomized controlled trial SETTING NHs of the state of Vaud, Switzerland PARTICIPANTS Of 157 total NHs in Vaud, 104 (67%) participated in the study. INTERVENTION Standard precautions were enforced in all participating NHs, and residents underwent MRSA screening at baseline and 12 months thereafter. All carriers identified in intervention NHs, either at study entry or among newly admitted residents, underwent topical decolonization combined with environmental disinfection, except in cases of MRSA infection, MRSA bacteriuria, or deep skin ulcers. RESULTS NHs were randomly allocated to a control group (51 NHs, 2,412 residents) or an intervention group (53 NHs, 2,338 residents). Characteristics of NHs and residents were similar in both groups. The mean screening rates were 86% (range, 27%-100%) in control NHs and 87% (20%-100%) in intervention NHs. Prevalence of MRSA carriage averaged 8.9% in both control NHs (range, 0%-43%) and intervention NHs (range, 0%-38%) at baseline, and this rate significantly declined to 6.6% in control NHs and to 5.8% in intervention NHs after 12 months. However, the decline did not differ between groups (P=.66). CONCLUSION Universal screening followed by decolonization of carriers did not significantly reduce the prevalence of the MRSA carriage rate at 1 year compared with standard precautions

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To make a comprehensive evaluation of organ-specific out-of-field doses using Monte Carlo (MC) simulations for different breast cancer irradiation techniques and to compare results with a commercial treatment planning system (TPS). Three breast radiotherapy techniques using 6MV tangential photon beams were compared: (a) 2DRT (open rectangular fields), (b) 3DCRT (conformal wedged fields), and (c) hybrid IMRT (open conformal+modulated fields). Over 35 organs were contoured in a whole-body CT scan and organ-specific dose distributions were determined with MC and the TPS. Large differences in out-of-field doses were observed between MC and TPS calculations, even for organs close to the target volume such as the heart, the lungs and the contralateral breast (up to 70% difference). MC simulations showed that a large fraction of the out-of-field dose comes from the out-of-field head scatter fluence (>40%) which is not adequately modeled by the TPS. Based on MC simulations, the 3DCRT technique using external wedges yielded significantly higher doses (up to a factor 4-5 in the pelvis) than the 2DRT and the hybrid IMRT techniques which yielded similar out-of-field doses. In sharp contrast to popular belief, the IMRT technique investigated here does not increase the out-of-field dose compared to conventional techniques and may offer the most optimal plan. The 3DCRT technique with external wedges yields the largest out-of-field doses. For accurate out-of-field dose assessment, a commercial TPS should not be used, even for organs near the target volume (contralateral breast, lungs, heart).

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BACKGROUND: Glioblastoma, the most common adult primary malignant brain tumor, confers poor prognosis (median survival of 15 months) notwithstanding aggressive treatment. Combination chemotherapy including carmustine (BCNU) or temozolomide (TMZ) with the MGMT inhibitor O6-benzylguanine (O6BG) has been used, but has been associated with dose-limiting hematopoietic toxicity. OBJECTIVE: To assess safety and efficacy of a retroviral vector encoding the O6BG-resistant MGMTP140K gene for transduction and autologous transplantation of hematopoietic stem cells (HSCs) in MGMT unmethylated, newly diagnosed glioblastoma patients in an attempt to chemoprotect bone marrowduring combination O6BG/TMZ therapy. METHODS: Three patients have been enrolled in the first cohort. Patients underwent standard radiation therapy without TMZ followed by G-CSF mobilization, apheresis, and conditioning with 600 mg/m2 BCNU prior to infusion of gene-modified cells. Posttransplant, patients were treated with 28-day cycles of single doseTMZ (472 mg/m2) with 48-hour intravenous O6BG (120 mg/m2 bolus, then 30 mg/m2/d). RESULTS: The BCNU dose was nonmyeloablative with ANC ,500/mL for ≤3 d and nadir thrombocytopenia of 28,000/mL. Gene marking in pre-infusion colony forming units (CFUs) was 70.6%, 79.0%, and 74.0% in Patients 1, 2, and 3, respectively, by CFU-PCR. Following engraftment, gene marking in white blood cells and sorted granulocytes ranged between 0.37-0.84 and 0.33-0.83 provirus copies, respectively, by real-time PCR. Posttransplant gene marking in CFUs from CD34-selected cells ranged from 28.5% to 47.4%. Patients have received 4, 3, and 2 cycles of O6BG/TMZ, respectively, with evidence for selection of gene-modified cells. One patient has received a single dose-escalated cycle at 590 mg/m2 TMZ. No additional extra-hematopoietic toxicity has been observed thus far and all three patients exhibit stable disease at 7-8 months since diagnosis CONCLUSIONS: We believe that these data demonstrate the feasibility of achieving significant engraftment of MGMTP140K-modified cells with a well-tolerated dose of BCNU. Further follow-up will determine whether this approach will allow for further dose escalation of TMZ and improved survival.

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BACKGROUND: Screening tests for subclinical cardiovascular disease, such as markers of atherosclerosis, are increasingly used in clinical prevention to identify individuals at high cardiovascular risk. Being aware of these test results might also enhance patient motivation to change unhealthy behaviors but the effectiveness of such a screening strategy has been poorly studied. METHODS: The CAROtid plaque Screening trial on Smoking cessation (CAROSS) is a randomized controlled trial in 530 regular smokers aged 40-70 years to test the hypothesis that carotid plaque screening will influence smokers' behavior with an increased rate of smoking cessation (primary outcome) and an improved control of other cardiovascular risk factors (secondary outcomes) after 1-year follow-up. All smokers will receive a brief advice for smoking cessation,and will subsequently be randomly assigned to either the intervention group (with plaques screening) or the control group (without plaque screening). Carotid ultrasound will be conducted with a standard protocol. Smokers with at least one carotid plaque will receive pictures of their own plaques with a structured explanation on the general significance of plaques. To ensure equal contact conditions, smokers not undergoing ultrasound and those without plaque will receive a relevant explanation on the risks associated with tobacco smoking. Study outcomes will be compared between smokers randomized to plaque screening and smokers not submitted to plaque screening. SUMMARY: This will be the first trial to assess the impact of carotid plaque screening on 1-year smoking cessation rates and levels of control of other cardiovascular risk factors.