29 research outputs found

    M+D: conceptual guidelines for compiling a materials library

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    This article proposes to present a study conducted by the Raw Materials research group, the results of which comprise the conceptual guidelines for compiling an M+D material library. The study includes the topic, materials and design taking the impact of the changes that came into being in the post industrial era on project methodologies and the search for information regarding materials. Taking into account the importance and complexity that these relationships have taken on currently, we have studied the issue of materials based on Manzini (1983) and Ashby and Johnson (2002). Afterward different databases and materials libraries located in the Brazil, the United States, France and Italy geared toward design professionals and students were analyzed to understand what information and means of access to them were available. The project methodologies were approached based on Löbach (1991), Bürdeck (1994), Schulmann (1994), Baxter (1998), Dantas (1998 and 2005) and Papanek (1995 and 2000). This study sought to identify the key elements of the role of materials in the project process today, to serve as a parameter for the analysis of the models studied. A comparative analysis of the models investigated enabled identification of positive and negative aspects to adapt to the needs previously mentioned and identify conceptual guidelines for compiling a collection of materials for use in design projects. Keywords: Design, Materials, Project Methodology, Library</p

    Approach to endoscopic extraperitoneal radical prostatectomy (EERPE): the impact of previous laparoscopic experience on the learning curve

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    BACKGROUND: We report our approach regarding the technique of endoscopic extraperitoneal radical prostatectomy (EERPE) and analyze the learning curve of two surgeons after thorough technical training under expert monitoring. The purpose of this study was to investigate the influence of expert monitoring on the surgical outcome and whether previous laparoscopic experience influences the surgeon's learning curve. METHODS: EERPE was performed on 120 consecutive patients by two surgeons with different experience in laparoscopy. An analysis and comparison of their learning curve was made. RESULTS: Median operation time: 200 (110-415) minutes. Complications: no conversion, blood transfusion (1.7%), rectal injury (3.3%). Median catheterisation time: 6 (5-45) days. Histopathological data: 55% pT2, 45% pT3 with a positive surgical margin rate of 6.1% and 46%, respectively. After 12 months, 78% of the patients were continent, 22% used 1 or more pad. Potency rate with or without PDE-5-inhibitors was 66% with bilateral and 31% with unilateral nerve-sparing, respectively. Operation time was the only parameter to differ significantly between the two surgeons. CONCLUSION: EERPE can be learned within a short teaching phase. Previous laparoscopic experience is reflected by shorter operation times, not by lower complication rates or superior early oncological data

    Autonomic modulation and antiarrhythmic therapy in a model of long QT syndrome type 3

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    AIMS: Clinical observations in patients with long QT syndrome carrying sodium channel mutations (LQT3) suggest that bradycardia caused by parasympathetic stimulation may provoke torsades de pointes (TdP). beta-Adrenoceptor blockers appear less effective in LQT3 than in other forms of the disease. METHODS AND RESULTS: We studied effects of autonomic modulation on arrhythmias in vivo and in vitro and quantified sympathetic innervation by autoradiography in heterozygous mice with a knock-in deletion (DeltaKPQ) in the Scn5a gene coding for the cardiac sodium channel and increased late sodium current (LQT3 mice). Cholinergic stimulation by carbachol provoked bigemini and TdP in freely roaming LQT3 mice. No arrhythmias were provoked by physical stress, mental stress, isoproterenol, or atropine. In isolated, beating hearts, carbachol did not prolong action potentials per se, but caused bradycardia and rate-dependent action potential prolongation. The muscarinic inhibitor AFDX116 prevented effects of carbachol on heart rate and arrhythmias. beta-Adrenoceptor stimulation suppressed arrhythmias, shortened rate-corrected action potential duration, increased rate, and minimized difference in late sodium current between genotypes. beta-Adrenoceptor density was reduced in LQT3 hearts. Acute beta-adrenoceptor blockade by esmolol, propranolol or chronic propranolol in vivo did not suppress arrhythmias. Chronic flecainide pre-treatment prevented arrhythmias (all P < 0.05). CONCLUSION: Cholinergic stimulation provokes arrhythmias in this model of LQT3 by triggering bradycardia. beta-Adrenoceptor density is reduced, and beta-adrenoceptor blockade does not prevent arrhythmias. Sodium channel blockade and beta-adrenoceptor stimulation suppress arrhythmias by shortening repolarization and minimizing difference in late sodium current.status: publishe

    Hemin-Modified SnO2/Metglas Electrodes for the Simultaneous Electrochemical and Magnetoelastic Sensing of H2O2

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    In this work, we present a simple and efficient method for the preparation of hemin-modified SnO2 films on Metglas ribbon substrates for the development of a sensitive magneto-electrochemical sensor for the determination of H2O2. The SnO2 films were prepared at low temperatures, using a simple hydrothermal method, compatible with the Metglas surface. The SnO2 film layer was fully characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), photoluminescence (PL) and Fourier Transform-Infrared spectroscopy (FT-IR). The properties of the films enable a high hemin loading to be achieved in a stable and functional way. The Hemin/SnO2-Metglas system was simultaneously used as a working electrode (WE) for cyclic voltammetry (CV) measurements and as a magnetoelastic sensor excited by external coils, which drive it to resonance and interrogate it. The CV scans reveal direct reduction and oxidation of the immobilized hemin, as well as good electrocatalytic response for the reduction of H2O2. In addition, the magnetoelastic resonance (MR) technique allows the detection of any mass change during the electroreduction of H2O2 by the immobilized hemin on the Metglas surface. The experimental results revealed a mass increase on the sensor during the redox reaction, which was calculated to be 767 ng/&mu;M. This behavior was not detected during the control experiment, where only the NaH2PO4 solution was present. The following results also showed a sensitive electrochemical sensor response linearly proportional to the concentration of H2O2 in the range 1 &times; 10&minus;6&ndash;72 &times; 10&minus;6 M, with a correlation coefficient of 0.987 and detection limit of 1.6 &times; 10&minus;7 M. Moreover, the Hemin/SnO2-Metglas displayed a rapid response (30 s) to H2O2 and exhibits good stability, reproducibility and selectivity

    Oncological long-term outcome of whole gland HIFU and open radical prostatectomy: a comparative analysis

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    Purpose To compare the oncological long-term efficacy of whole gland high-intensity focused ultrasound (HIFU) therapy and radical prostatectomy (RP) in patients with clinically localized prostate cancer. Methods 418 patients after open RP (1997-2004) were compared with 469 patients after whole gland HIFU (1997-2009) without preselection. Oncological follow-up focused on biochemical relapse, salvage treatment, life status and cause-specific mortality. The univariate log rank test was used to compare both treatment options regarding overall survival (OS), cancerspecific survival (CSS), biochemical failure-free survival (BFS) and salvage treatment-free survival (STS). To adjust the treatment effect for further prognostic baseline variables, a multivariable Cox proportional hazards regression model was calculated for each end point. Results Median follow-up was 13.3 years in the RP group and 6.5 years in the HIFU group. OS/CSS/BFS/STS rates at 10 years were 91/98/80/80% after RP and 76/94/70/ 71% after HIFU. HIFU therapy (reference RP) was a significant and independent predictor for an inferior OS, CSS and STS. In subgroup analysis, HIFU provided significantly reduced CSS for intermediate- (p = 0.010) and high-risk patients (p = 0.048); whereas no difference was observed in the low-risk group, intermediate-risk HIFU patients showed a significantly inferior STS (p = 0.040). Conclusions While whole gland HIFU offers a comparable long-term efficacy for low-risk patients, sufficient cancer control for high-risk patients is more than doubtful. For the subgroup of intermediate-risk patients, CSS rates seem to be comparable up to 10 years suggesting that HIFU may be an alternative for older patients, although a higher risk of salvage treatment should be expected

    Photodynamic Diagnosis for Superficial Bladder Cancer: Do All Risk-Groups Profit Equally from Oncological and Economic Long-Term Results?

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    Objective Photodynamic diagnosis (PDD) of superficial bladder cancer decreases recurrence rates. We present oncological results of a randomized, prospective study, comparing transurethral resection (TUR) performed under conventional white light (WL) with PDD. The follow-up period is the longest reported to date. As costs might be reimbursed by prolonged recurrence-free survival in certain patients cost analysis in regard to risk-groups was performed. Material and methods Using chi-square test and log-rank test we compared recurrence rates of 103 patients after WL-TUR and of 88 patients after PDD-TUR. Cost analysis was performed according to risk-groups of recurrence. Results Mean follow-up was 99 months. Recurrence rate was 57% in WL vs. 28% in PDD (p < 0.001). Costs incurred by subsequent TUR averaged € 2310 per WL patient vs. € 713 per PDD patient. Savings per patient by PDD amounted to € 1597. PDD costs were reimbursed in low, intermediate and high risk patients, respectively. Conclusions PDD-TUR is significantly superior to conventional WL-TUR in terms of recurrence rate. While economic benefit is most prominent in intermediate risk patients, PDD related costs are reimbursed in all risk-groups

    Oncological Long-term Outcome After Whole-gland High-intensity Focused Ultrasound for Prostate Cancer—21-yr Follow-up

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    Background: Owing to the morbidity of established radical treatment options for prostate cancer, alternative whole-gland and focal treatment strategies have emerged. High-intensity focused ultrasound (HIFU) is one of the most studied sources for tissue ablation and has been used since the 1990s. Objective: To provide 21-yr oncological long-term follow-up data of an unselected series of patients who underwent whole-gland HIFU for nonmetastatic prostYate cancer. Design, setting, and participants: A total of 674 patients were treated between November 1997 and November 2012 in one university center. Outcome measurements and statistical analysis: The oncological outcome was assessed by biopsy failure-free survival (BFFS), salvage treatment-free survival (STFS), metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS). Multivariable Cox proportional hazard regression analyses were performed to estimate the prognostic relevance of clinical variables. Results and limitations: In total, 560 patients were included into the evaluation and the median follow-up was 15.1 yr, with a range up to 21.4 yr. At 15 yr, CSS rates for low-, intermediate-, and high risk patients were 95%, 89%, and 65%, respectively; MFS, STFS-1 (salvage treatment other than HIFU), STFS-2 (salvage treatment including repeat HIFU), and BFFS rates were 91%, 85%, and 58%; 77%, 63%, and 29%; 67%, 52%, and 28%; and 82%, 73%, and 47%, respectively. Preoperative high-risk category was an independent predictor of inferior OS, CSS, MFS, STFS, and BFFS. Conclusions: Although whole-gland HIFU achieved good long-term cancer control in low and intermediate-risk patients, high-risk patients should not be treated routinely by HIFU. Intermediate-risk patients achieve high CSS and MFS rates, but a relevant salvage treatment rate has to be reckoned with. Long-term data after whole-gland therapy might help derive implications for focal treatment sources and patient selection. Patient summary: Long-term data after whole-gland high-intensity focused ultrasound (HIFU) therapy are crucial to prove its oncological efficacy, and may help derive implications for focal treatment strategies and patient selection. In this context, whole-gland HIFU achieved good long-term cancer control up to 21 yr in low-and intermediate-risk prostate cancer (PCa) patients. Owing to considerably inferior long-term cancer control, it should not routinely be used in high-risk PCa patients. (C) 2021 European Association of Urology. Published by Elsevier B.V. All rights reserved

    Prospective Multicenter Phase II Study on Focal Therapy (Hemiablation) of the Prostate with High Intensity Focused Ultrasound

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    Purpose: We evaluated focal therapy with high intensity focused ultrasound hemiablation in a prospective trial. Materials and Methods: We performed a prospective, multicenter, single arm study in patients with unilateral low/intermediate risk prostate cancer who were treated from April 2013 through March 2016 in Germany in AUO (Arbeitsgemeinschaft Urologische Onkologie) Study Protocol AP 68/11. Unilateral prostate cancer was assessed by transrectal ultrasound guided biopsy and multiparametric magnetic resonance imaging. Hemiablation was done using the Ablatherm (R) or the Focal One (R) device. The oncologic outcome was assessed by the salvage treatment rate, multiparametric magnetic resonance imaging and rebiopsy at 12 months. Functional outcome, quality of life, anxiety and depression were measured by validated questionnaires at baseline and every 3 months. Results: Of the 54 recruited patients 51 completed 12-month or greater visits. Mean +/- SD followup was 17.4 +/- 4.5 months. Mean prostate specific antigen decreased from 6.2 +/- 2.0 to 2.9 +/- 1.9 ng/ml at 12 months (p < 0.001). Biopsy at 12 months was positive for any prostate cancer and for clinically significant prostate cancer in 13 (26.5%) and 4 (8.2%) of the 49 patients, respectively. Posttreatment multiparametric magnetic resonance imaging had limited 25% sensitivity for clinically significant prostate cancer. Ten patients (19.6%) underwent salvage treatment. Potency was maintained in 21 of the 30 men who were potent preoperatively. There was no increase in incontinence. Quality of life, anxiety and depression did not change postoperatively. The study was limited by a short followup and the lack of a control arm. Conclusions: Focal therapy hemiablation is safe with little alteration of functional outcome. The oncologic outcome is acceptable on short-term followup. Followup multiparametric magnetic resonance imaging performed poorly and should not replace repeat biopsy. Focal therapy has no impact on posttreatment anxiety and depression
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