911 research outputs found
Macht en tegenmacht in de Nederlandse asbestregulering
De overheid moet haar excuses aanbieden aan slachtoffers en hun nabestaanden voor haar nalatigheid bij het treffen van tijdige en adequate maatregelen ter beperking van het gebruik van asbest. Dat stelt Robert Frank Ruers in zijn proefschrift "Macht en tegenmacht in de Nederlandse asbestregulering". Ook pleit hij voor een terugwerkende kracht van de Wet Verjaring Personenschade.
Aan het asbestverbod uit 1993 zijn conflicten tussen de asbestindustrie, de overheid, de vakbeweging en de slachtoffers voorafgegaan. De overheid was lange tijd nauwelijks bereid beperkingen aan het asbestgebruik te stellen. Asbestslachtoffers, zo’n bekende 10.000 slachtoffers, waarschijnlijk nog niet de helft van het uiteindelijke aantal, hebben pas recent aan invloed gewonnen.
Ruers onderzocht vier fasen van het asbestreguleringsproces tussen 1930 – 2004 en beschrijft de strategieën van de belangrijkste partijen, hun invloed en de impact hiervan op de juridische besluitvorming.
De strategie van de SP en het Comité Asbestslachtoffers heeft het reguleringsproces een beslissende wending gegeven, aldus Ruers. De internationale solidariteit tussen organisaties van asbestslachtoffers heeft bovendien haar meerwaarde bewezen op het gebied van historische kennisontwikkeling en juridische slagkracht.
Behalve voor de terugwerkende kracht van de Wet Verjaring Personenschade en de excuses pleit hij voor een op de wet gebaseerde algehele asbestinventarisatie
Broadband hyperspectral imaging for breast tumor detection using spectral and spatial information
Complete tumor removal during breast-conserving surgery remains challenging due to the lack of optimal intraoperative margin assessment techniques. Here, we use hyperspectral imaging for tumor detection in fresh breast tissue. We evaluated different wavelength ranges and two classification algorithms; a pixel-wise classification algorithm and a convolutional neural network that combines spectral and spatial information. The highest classification performance was obtained using the full wavelength range (450-1650nm). Adding spatial information mainly improved the differentiation of tissue classes within the malignant and healthy classes. High sensitivity and specificity were accomplished, which offers potential for hyperspectral imaging as a margin assessment technique to improve surgical outcome. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreemen
Method for coregistration of optical measurements of breast tissue with histopathology : the importance of accounting for tissue deformations
For the validation of optical diagnostic technologies, experimental results need to be benchmarked against the gold standard. Currently, the gold standard for tissue characterization is assessment of hematoxylin and eosin (H&E)-stained sections by a pathologist. When processing tissue into H&E sections, the shape of the tissue deforms with respect to the initial shape when it was optically measured. We demonstrate the importance of accounting for these tissue deformations when correlating optical measurement with routinely acquired histopathology. We propose a method to register the tissue in the H&E sections to the optical measurements, which corrects for these tissue deformations. We compare the registered H&E sections to H&E sections that were registered with an algorithm that does not account for tissue deformations by evaluating both the shape and the composition of the tissue and using microcomputer tomography data as an independent measure. The proposed method, which did account for tissue deformations, was more accurate than the method that did not account for tissue deformations. These results emphasize the need for a registration method that accounts for tissue deformations, such as the method presented in this study, which can aid in validating optical techniques for clinical use. (C) The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License
Monitoring of tumor radio frequency ablation using derivative spectroscopy
Despite the widespread use of radio frequency (RF) ablation, an effective way to assess thermal tissue damage during and after the procedure is still lacking. We present a method for monitoring RF ablation efficacy based on thermally induced methemoglobin as a marker for full tissue ablation. Diffuse reflectance (DR) spectra were measured from human blood samples during gradual heating of the samples from 37 to 60, 70, and 85°C. Additionally, reflectance spectra were recorded real-time during RF ablation of human liver tissue ex vivo and in vivo. Specific spectral characteristics of methemoglobin were extracted from the spectral slopes using a custom optical ablation ratio. Thermal coagulation of blood caused significant changes in the spectral slopes, which is thought to be caused by the formation of methemoglobin. The time course of these changes was clearly dependent on the heating temperature. RF ablation of liver tissue essentially led to similar spectral alterations. In vivo DR measurements confirmed that the method could be used to assess the degree of thermal damage during RF ablation and long after the tissue cooled
Optical biopsy of epithelial cancers by optical coherence tomography
Optical coherence tomography (OCT) is an optical technique that measures the backscattering of near-infrared light by tissue. OCT yields in 2D and 3D images at micrometer-scale resolution, thus providing optical biopsies, approaching the resolution of histopathological imaging. The technique has shown to allow in vivo differentiation between benign and malignant epithelial tissue, through qualitative assessment of OCT images, as well as by quantitative evaluation, e.g., functional OCT. This study aims to summarize the principles of OCT and to discuss the current literature on the diagnostic value of OCT in the diagnosis of epithelial (pre)malignant lesions. The authors did a systematic search of the electronic databases PubMed and Embase on OCT in the diagnostic process of (pre)malignant epithelial lesions. OCT is able to differentiate between benign and (pre)malignant lesions of epithelial origin in a wide variety of tissues. In this way, OCT can detect skin cancers, oral, laryngeal, and esophageal cancer as well as genital and bladder cancer. OCT is an innovative technique which enables an optical biopsy of epithelial lesions. The incorporation of OCT in specific tools, like handheld and catheter-based probes, will further improve the implementation of this technology in daily clinical practice
Evidence for Two Modes of Synergistic Induction of Apoptosis by Mapatumumab and Oxaliplatin in Combination with Hyperthermia in Human Colon Cancer Cells
Colorectal cancer is the third leading cause of cancer-related mortality in the world-- the main cause of death from colorectal cancer is hepatic metastases, which can be treated with isolated hepatic perfusion (IHP). Searching for the most clinically relevant approaches for treating colorectal metastatic disease by isolated hepatic perfusion (IHP), we developed the application of oxaliplatin concomitantly with hyperthermia and humanized death receptor 4 (DR4) antibody mapatumumab (Mapa), and investigated the molecular mechanisms of this multimodality treatment in human colon cancer cell lines CX-1 and HCT116 as well as human colon cancer stem cells Tu-12, Tu-21 and Tu-22. We showed here, in this study, that the synergistic effect of the multimodality treatment-induced apoptosis was caspase dependent and activated death signaling via both the extrinsic apoptotic pathway and the intrinsic pathway. Death signaling was activated by c-Jun N-terminal kinase (JNK) signaling which led to Bcl-xL phosphorylation at serine 62, decreasing the anti-apoptotic activity of Bcl-xL, which contributed to the intrinsic pathway. The downregulation of cellular FLICE inhibitory protein long isoform (c-FLIPL) in the extrinsic pathway was accomplished through ubiquitination at lysine residue (K) 195 and protein synthesis inhibition. Overexpression of c-FLIPL mutant (K195R) and Bcl-xL mutant (S62A) completely abrogated the synergistic effect. The successful outcome of this study supports the application of multimodality strategy to patients with colorectal hepatic metastases who fail to respond to standard chemoradiotherapy that predominantly targets the mitochondrial apoptotic pathway. © 2013 Song et al
Detection of Melanoma Metastases in Resected Human Lymph Nodes by Noninvasive Multispectral Photoacoustic Imaging
Objective. Sentinel node biopsy in patients with cutaneous melanoma improves staging, provides prognostic information, and leads to an increased survival in node-positive patients. However, frozen section analysis of the sentinel node is not reliable and definitive histopathology evaluation requires days, preventing intraoperative decision-making and immediate therapy. Photoacoustic imaging can evaluate intact lymph nodes, but specificity can be hampered by other absorbers such as hemoglobin. Near infrared multispectral photoacoustic imaging is a new approach that has the potential to selectively detect melanin. The purpose of the present study is to examine the potential of multispectral photoacoustic imaging to identify melanoma metastasis in human lymph nodes. Methods. Three metastatic and nine benign lymph nodes from eight melanoma patients were scanned ex vivo using a Vevo LAZR multispectral photoacoustic imager and were spectrally analyzed per pixel. The results were compared to histopathology as gold standard. Results. The nodal volume could be scanned within 20 minutes. An unmixing procedure was proposed to identify melanoma metastases with multispectral photoacoustic imaging. Ultrasound overlay enabled anatomical correlation. The penetration depth of the photoacoustic signal was up to 2 cm. Conclusion. Multispectral three-dimensional photoacoustic imaging allowed for selective identification of melanoma metastases in human lymph nodes
Local Treatment of Unresectable Colorectal Liver Metastases: Results of a Randomized Phase II Trial
BACKGROUND: Tumor ablation is often employed for unresectable colorectal liver metastases. However, no survival benefit has ever been demonstrated in prospective randomized studies. Here, we investigate the long-term benefits of such an aggressive approach. METHODS: In this randomized phase II trial, 119 patients with unresectable colorectal liver metastases (n 38%) was met. We now report on long-term OS results. All statistical tests were two-sided. The analyses were according to intention to treat. RESULTS: At a median follow up of 9.7 years, 92 of 119 (77.3%) patients had died: 39 of 60 (65.0%) in the combined modality arm and 53 of 59 (89.8%) in the systemic treatment arm. Almost all patients died of progressive disease (35 patients in the combined modality arm, 49 patients in the systemic treatment arm). There was a statistically significant difference in OS in favor of the combined modality arm (hazard ratio [HR] = 0.58, 95% confidence interval [CI] = 0.38 to 0.88, P = .01). Three-, five-, and eight-year OS were 56.9% (95% CI = 43.3% to 68.5%), 43.1% (95% CI = 30.3% to 55.3%), 35.9% (95% CI = 23.8% to 48.2%), respectively, in the combined modality arm and 55.2% (95% CI = 41.6% to 66.9%), 30.3% (95% CI = 19.0% to 42.4%), 8.9% (95% CI = 3.3% to 18.1%), respectively, in the systemic treatment arm. Median OS was 45.6 months (95% CI = 30.3 to 67.8 months) in the combined modality arm vs 40.5 months (95% CI = 27.5 to 47.7 months) in the systemic treatment arm. CONCLUSIONS: This phase II trial is the first randomized study demonstrating that aggressive local treatment can prolong OS in patients with unresectable colorectal liver metastases
Integration of Visual SLAM in Robot-Assisted Minimally Invasive Surgery:Advances, Challenges, and Solutions
Robot-assisted surgery (RAS) has demonstrated notable advancements in visualization, instrument dexterity, ergonomic improvements, and decreased infection risks when compared to conventional surgical methods. However, within minimally invasive surgery (MIS) contexts, RAS encounters notable challenges in navigating surgical tools effectively. Recent advancements in robot navigation techniques have transitioned from rudimentary wheel odometry and dead reckoning to sophisticated Visual SLAM (Simultaneous Localization and Mapping) methods, capable of addressing complex indoor and outdoor environments. Nevertheless, the integration of Visual SLAM within Robot-Assisted Minimally Invasive Surgery (RAMIS) applications remains substantially restricted due to various factors, including limited field of view, challenges in stereopsis, soft tissue deformations, insufflation effects, and instrument occlusions. This study provides an extensive overview of ongoing efforts towards the development of Visual SLAM algorithms tailored for establishing precise RAMIS systems. It delves into the encountered challenges, delineates the essential features required for establishing a precise Visual SLAM-driven RAMIS system, and explores a diverse range of approaches, which can potentially enhance Visual SLAM functionality within RAMIS contexts.</p
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