Ce travail a été soutenu par des subventions du Programme de recherche en collaboration et à l&#39;expérience de formation (CREATE) et une subvention à la découverte des sciences naturelles et en génie (CRSNG) du Canada.

Les auteurs n&#39;ont rien à révéler.

Nous avons présenté une série de techniques sophistiquées de traitement de l&#39;image numérique et la reconnaissance des formes, aussi connu comme l&#39;apprentissage machine et CAD, pour la détection de distorsion architecturale dans les mammographies antérieures de cas intervalle-cancer. Les méthodes sont basées sur l&#39;analyse des modèles de texture orientées présents dans les images mammographiques. Nos méthodes, y compris plusieurs autres fonctionnalités proposées dans nos travaux connexes, sont c...

Le cancer du sein est une maladie grave qui touche les femmes et est la deuxième cause de cancer lié décès chez les femmes 1,2. Afin d&#39;améliorer les chances de survie et le pronostic des patients affectés par un traitement efficace à des stades précoces du cancer du sein, la maladie doit être détectée le plus rapidement possible. Dans l&#39;analyse rétrospective des cas de cancer du sein, des signes subtils d&#39;anomalies ont été observées sur les mammographies de dépistage précédemment acquis 3,4. Distorsion architecturale est un tel signe mammographique localisée éventuellement stades précoces du cancer du sein qui est difficile à détecter 5,6. Les modèles associés sont vaguement décrits comme une distorsion de l&#39;architecture normale du sein sans visible masse définie. Distorsion architecturale pourrait apparaître dans les premières étapes de la formation d&#39;une masse au sein ou une tumeur. Nous émettons l&#39;hypothèse que les mammographies de dépistage obtenus avant la détection du cancer du sein could contient signes subtils de stades précoces du cancer du sein, en particulier, distorsion architecturale. La figure 1a montre une image avant mammographique d&#39;un cas de cancer de l&#39;écran détecté. La région de l&#39;anomalie identifiée par un radiologue (JELD) est décrit par un rectangle rouge. La mammographie a été prise avant 24 mois avant la mammographie de détection de la figure 1b. La mammographie avant avait été déclaré exempt de signes d&#39;un cancer à l&#39;instance d&#39;origine de dépistage. Dans une analyse rétrospective et en comparaison avec la mammographie de dépistage, une région suspecte liée au site de cancer détecté a été marqué par le radiologue, et est indiquée en rouge sur la mammographie avant. La région suspecte contient des signes de distorsion architecturale, y compris les spicules. diagnostic (CAD) des techniques et des systèmes assistés par ordinateur offrent le potentiel pour atteindre une sensibilité accrue dans la détection de Breast cancer 2,7-9. Cependant, en comparaison avec le nombre de publications qui existent dans la littérature sur la détection d&#39;autres signes de cancer du sein, tels que les masses et les calcifications, seul un petit nombre d&#39;études ont été rapportées sur la détection de distorsion architecturale en l&#39;absence d&#39;un masse centrale 10-17. Les systèmes de CAO disponibles dans le commerce ont été trouvés à des résultats médiocres pour la détection de distorsion d&#39;architecture 18. Les études sur la détection de distorsion architecturale dans les mammographies antérieures de cas dépistés ou intervalle-cancer 3,4,19-22 pourrait aider à élaborer des stratégies pour la détection et le traitement des maladies du sein à un stade précoce, et conduire à l&#39;amélioration de la pronostic pour le patient 23. Préparation des images pour l&#39;expérience Des expériences ont été menées avec 158 images mammographiques dont 106 mammographies antérieures de 56 personnes diagnostiquéesun cancer du sein et 52 images de 13 individus normaux. L&#39;approbation éthique pour l&#39;étude a été obtenue du Conseil Conjoint santé éthique de la recherche, Bureau de bioéthique médicale, Université de Calgary, et la Calgary Regional Health Authority. Les images ont été obtenues à partir de Screen Test: Programme de l&#39;Alberta pour la détection précoce du cancer du sein 21,24,25. Les mammographies acquis dans la dernière visite prévue au programme de dépistage avant le diagnostic de cancer en dehors du programme de dépistage ont été étiquetés comme des mammographies antérieures de cas intervalle-cancer. Les mammographies diagnostiques correspondants n&#39;étaient pas disponibles. Tous, sauf deux des 106 mammographies antérieures avaient été déclarés exempts de tout signe de cancer du sein au moment de leur acquisition et d&#39;analyse dans le programme de dépistage, les personnes correspondant aux deux autres mammographies ont été renvoyés pour la biopsie. L&#39;intervalle de temps entre le diagnostic du cancer et des mammographies antérieures variait de 1,5 moiss à 24,5 mois, avec une moyenne de 15 mois et l&#39;écart type de 7 mois. Tous les mammographies antérieures de cas intervalle cancer disponibles dans la base de données ont été inclus dans la présente étude, à l&#39;exception de six images dans lesquelles aucune pièce suspects ont pu être identifiés. Les mammographies film-écran ont été numérisées à la résolution spatiale de 50 um et la résolution d&#39;échelle de gris 12 bits par pixel en utilisant le Lumiscan 85 scanner laser (Lumisys, Sunnyvale, CA). Un radiologue expert spécialisé en mammographie (JELD) a examiné toutes les 106 mammographies antérieures de cas intervalle cancer et a marqué les régions suspectées de distorsion architecturale avec des boîtes rectangulaires sur la base des rapports disponibles sur l&#39;imagerie ou une biopsie ultérieure, ou par inspection détaillée des mammographies . Sur les 106 images mammographiques antérieurs dans la base de données utilisée dans la présente étude, 38 images ont distorsion architecturale visible, et les 68 images restantes contiennent ev discutable ou pas clairementident distorsion architecturale. Chaque mammographie avant contient un seul site de distorsion architecturale identifiés par la boîte rectangulaire dessinée par le radiologue. La largeur moyenne, la hauteur et la zone des 106 parties suspectes d&#39;images marquées par le radiologue sont 56 mm, 39 mm et 2274 mm 2, avec un écart type de 11,8 mm, 11,6 mm et 1073,9 mm 2, respectivement.

detection of architectural distortion in prior mammograms via analysis of oriented patterns

Nous démontrons méthodes pour la détection de distorsion architecturale dans les mammographies antérieures de cas intervalle cancéreux fondés sur l&#39;analyse de l&#39;orientation des motifs des tissus mammaires à la mammographie. Nous émettons l&#39;hypothèse que la distorsion architecturale modifie l&#39;orientation normale de motifs de tissus mammaires en images mammographiques avant la formation de masses ou des tumeurs. Dans les premières étapes de nos méthodes, les structures orientées dans une mammographie donné sont analysés en utilisant les filtres de Gabor et des portraits de phase pour détecter les sites de noeud-comme de rayonnement ou intersection motifs de tissus. Chaque site est ensuite détectée, caractérisé en utilisant la valeur de noeud, la dimension fractale, et une mesure de la dispersion angulaire spécifiquement conçu pour représenter les motifs de spiculating associés à une distorsion architecturale. Nos méthodes ont été testées avec une base de données de 106 mammographies antérieures de 56 cas intervalle-cancer et 52 mammographies de 13 cas normales en utilisant les fonctionnalités développées pour laCaractérisation de la distorsion d&#39;architecture, de classification de formes par l&#39;intermédiaire d&#39;une analyse discriminante quadratique, et la validation de la procédure leave-one-out du patient. Selon les résultats de libre-réponse récepteur fonctionnant analyse caractéristique, nos méthodes ont démontré la capacité de détecter une distorsion architecturale dans les mammographies antérieures, pris 15 mois (en moyenne) avant le diagnostic clinique du cancer du sein, avec une sensibilité de 80% à environ cinq faux positifs par patient.

Les trois fonctions, à savoir, la valeur de nœud, FD, et H F, les valeurs d&#39;AUC prévues de 0,61, 0,59, et 0,64, respectivement, lorsque chaque élément a été utilisé sur son propre. L&#39;utilisation combinée des trois fonctions fourni une performance améliorée avec la CUA = 0,70. La courbe de FROC obtenu avec la combinaison des trois éléments est représenté sur la figure 11, ce qui indique une sensibilité de 80% à 5,6 MF / patient et 89% à 7,5 MF / patient. Util...

Watch this Scientific Journal Video about Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns at JoVE.com

Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns

Nous démontrons méthodes pour la détection de distorsion architecturale dans les mammographies antérieures. Structures orientées sont analysés en utilisant des filtres de Gabor et des portraits de phase pour détecter les sites de motifs rayonnants de tissus. Chaque site est caractérisé et classé à l&#39;aide de mesures pour représenter les modèles de spiculating. Les méthodes devraient aider à la détection du cancer du sein.

Détection de distorsion architecturale dans mammographies antérieures<em&gt; Par</em&gt; Analyse des modèles orientés

We demonstrate methods for the detection of architectural distortion in prior mammograms of interval-cancer cases based on analysis of the orientation of ...

detection-architectural-distortion-prior-mammograms-via-analysis

Research

JoVE Journal

Medicine

Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns

42.5K vues.  University of Calgary.  Nous démontrons méthodes pour la détection de distorsion architecturale dans les mammographies antérieures. Structures orientées sont analysés en utilisant des filtres de Gabor et des portraits de phase pour détecter les sites de motifs rayonnants de tissus. Chaque site est caractérisé et classé à l'aide de mesures pour représenter les modèles de spiculating. Les méthodes devraient aider à la détection du cancer du sein. 

Vidéo: Detection of Architectural Distortion in Prior Mammograms via Analysis of Oriented Patterns

Production and Detection of Reactive Oxygen Species (ROS) in Cancers

Reactive oxygen species include a number of molecules that damage DNA and RNA and oxidize proteins and lipids (lipid peroxydation). These reactive molecules contain an oxygen and include H2O2 (hydrogen peroxide), NO (nitric oxide), O2- (oxide anion), peroxynitrite (ONOO-), hydrochlorous acid (HOCl), and hydroxyl radical (OH-).
Oxidative species are produced not only under pathological situations (cancers, ischemic/reperfusion, neurologic and cardiovascular pathologies, infectious diseases, inflammatory diseases 1, autoimmune diseases 2, etc&hellip;) but also during physiological (non-pathological) situations such as cellular metabolism 3, 4. Indeed, ROS play important roles in many cellular signaling pathways (proliferation, cell activation 5, 6, migration 7 etc..). ROS can be detrimental (it is then referred to as "oxidative and nitrosative stress") when produced in high amounts in the intracellular compartments and cells generally respond to ROS by upregulating antioxidants such as superoxide dismutase (SOD) and catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) that protects them by converting dangerous free radicals to harmless molecules (i.e. water). Vitamins C and E have also been described as ROS scavengers (antioxidants).
Free radicals are beneficial in low amounts 3. Macrophage and neutrophils-mediated immune responses involve the production and release of NO, which inhibits viruses, pathogens and tumor proliferation 8. NO also reacts with other ROS and thus, also has a role as a detoxifier (ROS scavenger). Finally NO acts on vessels to regulate blood flow which is important for the adaptation of muscle to prolonged exercise 9, 10. Several publications have also demonstrated that ROS are involved in insulin sensitivity 11, 12.
Numerous methods to evaluate ROS production are available. In this article we propose several simple, fast, and affordable assays; these assays have been validated by many publications and are routinely used to detect ROS or its effects in mammalian cells. While some of these assays detect multiple ROS, others detect only a single ROS.

Production and Detection of Reactive Oxygen Species ROS in Cancers

Here we propose simple methods to test and evaluate the presence of reactive oxygen species in cells.

Production et détection d&#39;espèces réactives de l&#39;oxygène (ROS) dans les cancers

Reactive oxygen species include a number of molecules that damage DNA and RNA and oxidize proteins and lipids (lipid peroxydation). These reactive ...

Recherche

Médecine

Cerenkov Luminescence Imaging (CLI) for Cancer Therapy Monitoring

In molecular imaging, positron emission tomography (PET) and optical imaging (OI) are two of the most important and thus most widely used modalities1-3. PET is characterized by its excellent sensitivity and quantification ability while OI is notable for non-radiation, relative low cost, short scanning time, high throughput, and wide availability to basic researchers. However, both modalities have their shortcomings as well. PET suffers from poor spatial resolution and high cost, while OI is mostly limited to preclinical applications because of its limited tissue penetration along with prominent scattering optical signals through the thickness of living tissues.
 Recently a bridge between PET and OI has emerged with the discovery of Cerenkov Luminescence Imaging (CLI)4-6. CLI is a new imaging modality that harnesses Cerenkov Radiation (CR) to image radionuclides with OI instruments. Russian Nobel laureate Alekseyevich Cerenkov and his colleagues originally discovered CR in 1934. It is a form of electromagnetic radiation emitted when a charged particle travels at a superluminal speed in a dielectric medium7,8. The charged particle, whether positron or electron, perturbs the electromagnetic field of the medium by displacing the electrons in its atoms. After passing of the disruption photons are emitted as the displaced electrons return to the ground state. For instance, one 18F decay was estimated to produce an average of 3 photons in water5. 
 Since its emergence, CLI has been investigated for its use in a variety of preclinical applications including in vivo tumor imaging, reporter gene imaging, radiotracer development, multimodality imaging, among others4,5,9,10,11. The most important reason why CLI has enjoyed much success so far is that this new technology takes advantage of the low cost and wide availability of OI to image radionuclides, which used to be imaged only by more expensive and less available nuclear imaging modalities such as PET.
 Here, we present the method of using CLI to monitor cancer drug therapy. Our group has recently investigated this new application and validated its feasibility by a proof-of-concept study12. We demonstrated that CLI and PET exhibited excellent correlations across different tumor xenografts and imaging probes. This is consistent with the overarching principle of CR that CLI essentially visualizes the same radionuclides as PET. We selected Bevacizumab (Avastin; Genentech/Roche) as our therapeutic agent because it is a well-known angiogenesis inhibitor13,14. Maturation of this technology in the near future can be envisioned to have a significant impact on preclinical drug development, screening, as well as therapy monitoring of patients receiving treatments.

Cerenkov Luminescence Imaging CLI for Cancer Therapy Monitoring

Use of Cerenkov Luminescence Imaging (CLI) for monitoring preclinical cancer treatment is described here. This method takes advantage of Cerenkov Radiation (CR) and optical imaging (OI) to visualize radiolabeled probes and thus provides an alternative to PET in preclinical therapeutic monitoring and drug screening.

Luminescence Cerenkov Imaging (CLI) pour la surveillance de la thérapie du cancer

In  molecular imaging, positron emission tomography (PET) and optical imaging (OI)  are two of the most important and thus most widely used modalities1-3. ...

Identification of Disease-related Spatial Covariance Patterns using Neuroimaging Data

The scaled subprofile model (SSM)1-4 is a multivariate PCA-based algorithm that identifies major sources of variation in patient and control group brain image data while rejecting lesser components (Figure 1). Applied directly to voxel-by-voxel covariance data of steady-state multimodality images, an entire group image set can be reduced to a few significant linearly independent covariance patterns and corresponding subject scores. Each pattern, termed a group invariant subprofile (GIS), is an orthogonal principal component that represents a spatially distributed network of functionally interrelated brain regions. Large global mean scalar effects that can obscure smaller network-specific contributions are removed by the inherent logarithmic conversion and mean centering of the data2,5,6. Subjects express each of these patterns to a variable degree represented by a simple scalar score that can correlate with independent clinical or psychometric descriptors7,8. Using logistic regression analysis of subject scores (i.e. pattern expression values), linear coefficients can be derived to combine multiple principal components into single disease-related spatial covariance patterns, i.e. composite networks with improved discrimination of patients from healthy control subjects5,6. Cross-validation within the derivation set can be performed using bootstrap resampling techniques9. Forward validation is easily confirmed by direct score evaluation of the derived patterns in prospective datasets10. Once validated, disease-related patterns can be used to score individual patients with respect to a fixed reference sample, often the set of healthy subjects that was used (with the disease group) in the original pattern derivation11. These standardized values can in turn be used to assist in differential diagnosis12,13 and to assess disease progression and treatment effects at the network level7,14-16. We present an example of the application of this methodology to FDG PET data of Parkinson's Disease patients and normal controls using our in-house software to derive a characteristic covariance pattern biomarker of disease.

Multivariate techniques including principal component analysis (PCA) have been used to identify signature patterns of regional change in functional brain images. We have developed an algorithm to identify reproducible network biomarkers for the diagnosis of neurodegenerative disorders, assessment of disease progression, and objective evaluation of treatment effects in patient populations.

Identification des modèles de covariance spatiale liés à la maladie en utilisant des données de neuro-imagerie

The scaled subprofile model (SSM)1-4 is a multivariate PCA-based algorithm that identifies major sources of variation in patient and control group brain ...

Carotid Artery Infusions for Pharmacokinetic and Pharmacodynamic Analysis of Taxanes in Mice

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study model. As the use of mouse models are often a vital step in preclinical drug discovery and drug development1-8, it is necessary to design a system to introduce drugs into mice in a uniform, reproducible manner. Ideally, the system should permit the collection of blood samples at regular intervals over a set time course. The ability to measure drug concentrations by mass-spectrometry, has allowed investigators to follow the changes in plasma drug levels over time in individual mice1, 9, 10. In this study, paclitaxel was introduced into transgenic mice as a continuous arterial infusion over three hours, while blood samples were simultaneously taken by retro-orbital bleeds at set time points. Carotid artery infusions are a potential alternative to jugular vein infusions, when factors such as mammary tumors or other obstructions make jugular infusions impractical. Using this technique, paclitaxel concentrations in plasma and tissue achieved similar levels as compared to jugular infusion. In this tutorial, we will demonstrate how to successfully catheterize the carotid artery by preparing an optimized catheter for the individual mouse model, then show how to insert and secure the catheter into the mouse carotid artery, thread the end of the catheter out through the back of the mouse&#8217;s neck, and hook the mouse to a pump to deliver a controlled rate of drug influx. Multiple low volume retro-orbital bleeds allow for analysis of plasma drug concentrations over time.

This method was developed with the goal of delivering a steady drug solution via the carotid artery, to assess the pharmacokinetics of novel drugs in mouse models.

Infusions de l&#39;artère carotide pour pharmacocinétiques et pharmacodynamiques Analyse des taxanes chez la souris

When proposing the use of a drug, drug combination, or drug delivery into a novel system, one must assess the pharmacokinetics of the drug in the study ...

Tracking the Mammary Architectural Features and Detecting Breast Cancer with Magnetic Resonance Diffusion Tensor Imaging

Breast cancer is the most common cause of cancer among women worldwide. Early detection of breast cancer has a critical role in improving the quality of life and survival of breast cancer patients. In this paper a new approach for the detection of breast cancer is described, based on tracking the mammary architectural elements using diffusion tensor imaging (DTI). 
The paper focuses on the scanning protocols and image processing algorithms and software that were designed to fit the diffusion properties of the mammary fibroglandular tissue and its changes during malignant transformation. The final output yields pixel by pixel vector maps that track the architecture of the entire mammary ductal glandular trees and parametric maps of the diffusion tensor coefficients and anisotropy indices. 
The efficiency of the method to detect breast cancer was tested by scanning women volunteers including 68 patients with breast cancer confirmed by histopathology findings. Regions with cancer cells exhibited a marked reduction in the diffusion coefficients and in the maximal anisotropy index as compared to the normal breast tissue, providing an intrinsic contrast for delineating the boundaries of malignant growth. Overall, the sensitivity of the DTI parameters to detect breast cancer was found to be high, particularly in dense breasts, and comparable to the current standard breast MRI method that requires injection of a contrast agent. Thus, this method offers a completely non-invasive, safe and sensitive tool for breast cancer detection.

We describe how to obtain parametric and vector maps of the diffusion tensor of the breast using magnetic resonance imaging. The protocol and final output following imaging processing are tailored for tracking breast architectural features and detecting breast malignancy.

Suivi Les caractéristiques architecturales mammaires et la détection de cancer du sein avec résonance magnétique Diffusion Tensor Imaging

Breast cancer is the most common cause of cancer among women worldwide. Early detection of breast cancer has a critical role in improving the quality of ...

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a serious problem. Therefore, the acceptance criteria for organ donors have been extended leading to the usage of marginal kidney grafts. These marginal organs tolerate cold storage poorly resulting in increased preservation injury and higher rates of delayed graft function. To overcome the limitations of cold storage, extensive research is focused on alternative normothermic preservation methods.
Ex vivo normothermic organ perfusion is an innovative preservation technique. The first experimental and clinical trials for ex vivo lung, liver, and kidney perfusions demonstrated favorable outcomes.
In addition to the reduction of cold ischemic injury, the method of normothermic kidney storage offers the opportunity for organ assessment and repair. This manuscript provides information about kidney retrieval, organ preservation techniques, and isolated ex vivo normothermic kidney perfusion (NEVKP) in a porcine model. Surgical techniques, set up for the perfusion solution and the circuit, potential assessment options, and representative results are demonstrated.

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation

The severe organ shortage has resulted in increased use of marginal kidney grafts for transplantation. This has triggered interest in alternative storage methods, since marginal grafts especially tolerate cold storage poorly. The technique of normothermic ex vivo kidney perfusion (NEVKP) represents a novel preservation method for kidney grafts prior to &#160;transplantation.

Normothermique<em&gt; Ex Vivo</em&gt; Kidney Perfusion pour la préservation du rein Greffes avant la transplantation

Kidney transplantation has become a well-established treatment option for patients with end-stage renal failure. The persisting organ shortage remains a ...

VDJ-Seq: Deep Sequencing Analysis of Rearranged Immunoglobulin Heavy Chain Gene to Reveal Clonal Evolution Patterns of B Cell Lymphoma

Understanding tumor clonality is critical to understanding the mechanisms involved in tumorigenesis and disease progression. In addition, understanding the clonal composition changes that occur within a tumor in response to certain micro-environment or treatments may lead to the design of more sophisticated and effective approaches to eradicate tumor cells. However, tracking tumor clonal sub-populations has been challenging due to the lack of distinguishable markers. To address this problem, a VDJ-seq protocol was created to trace the clonal evolution patterns of diffuse large B cell lymphoma (DLBCL) relapse by exploiting VDJ recombination and somatic hypermutation (SHM), two unique features of B cell lymphomas.
In this protocol, Next-Generation sequencing (NGS) libraries with indexing potential were constructed from amplified rearranged immunoglobulin heavy chain (IgH) VDJ region from pairs of primary diagnosis and relapse DLBCL samples. On average more than half million VDJ sequences per sample were obtained after sequencing, which contain both VDJ rearrangement and SHM information. In addition, customized bioinformatics pipelines were developed to fully utilize sequence information for the characterization of IgH-VDJ repertoire within these samples. Furthermore, the pipeline allows the reconstruction and comparison of the clonal architecture of individual tumors, which enables the examination of the clonal heterogeneity within the diagnosis tumors and deduction of clonal evolution patterns between diagnosis and relapse tumor pairs. When applying this analysis to several diagnosis-relapse pairs, we uncovered key evidence that multiple distinctive tumor evolutionary patterns could lead to DLBCL relapse. Additionally, this approach can be expanded into other clinical aspects, such as identification of minimal residual disease, monitoring relapse progress and treatment response, and investigation of immune repertoires in non-lymphoma contexts.

This protocol describes an approach to interrogate the recombined immunoglobulin heavy chain VDJ regions of lymphomas by deep-sequencing and retrieve VDJ rearrangement and somatic hypermutation status to delineate clonal architecture of individual tumor. Comparing clonal architecture between paired diagnosis and relapse samples reveals lymphoma relapse clonal evolution modes.

VDJ-Seq: Analyse en profondeur de séquençage de Rearranged immunoglobuline chaîne lourde Gene à révéler des modèles clonale évolution de B Lymphome

Understanding tumor clonality is critical to understanding the mechanisms involved in tumorigenesis and disease progression. In addition, understanding ...

Depletion of Mouse Cells from Human Tumor Xenografts Significantly Improves Downstream Analysis of Target Cells

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic patient tumors in different assays1. Human tumor xenografts represent the gold standard with respect to tumor biology, drug discovery, and metastasis research 2-4. Tumor xenografts can be derived from different types of material like tumor cell lines, tumor tissue from primary patient tumors4 or serially transplanted tumors. When propagated in vivo, xenografted tissue is infiltrated and vascularized by cells of mouse origin. Multiple factors such as the tumor entity, the origin of xenografted material, growth rate and region of transplantation influence the composition and the amount of mouse cells present in tumor xenografts. However, even when these factors are kept constant, the degree of mouse cell contamination is highly variable.
Contaminating mouse cells significantly impair downstream analyses of human tumor xenografts. As mouse fibroblasts show high plating efficacies and proliferation rates, they tend to overgrow cultures of human tumor cells, especially slowly proliferating subpopulations. Mouse cell derived DNA, mRNA, and protein components can bias downstream gene expression analysis, next-generation sequencing, as well as proteome analysis 5. To overcome these limitations, we have developed a fast and easy method to isolate untouched human tumor cells from xenografted tumor tissue. This procedure is based on the comprehensive depletion of cells of mouse origin by combining automated tissue dissociation with the benchtop tissue dissociator and magnetic cell sorting. Here, we demonstrate that human target cells can be can be obtained with purities higher than 96% within less than 20 min independent of the tumor type.

Human tumor xenografts are vascularized and infiltrated by cells of mouse origin during the growth phase in vivo. To circumvent the bias caused by these contaminating cells during downstream analysis, we developed a method allowing for comprehensive depletion of all mouse cells by magnetic cell sorting.

Appauvrissement des cellules de souris de xénogreffes de tumeurs humaines améliore de manière significative l&#39;analyse en aval des cellules cibles

The use of in vitro cell line models for cancer research has been a useful tool. However, it has been shown that these models fail to reliably mimic ...

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. To better understand the mechanism behind these surgical procedures, a rat partial liver transplantation (PLTx) model was established for relevant surgical studies. Because of the complexity of the rat PLTx model, a protocol with detailed descriptions is required. An article published previously reported a protocol in which ex vivo hepatectomy was used to achieve 50% rat PLTx. In contrast to this protocol, we introduced a re-arterialized PLTx with an in vivo 70% hepatectomy. An updated vessel-oriented hepatectomy was incorporated into the rat PLTx to refine the microsurgical procedure. The portal veins and hepatic arteries of the left lateral lobe and the median lobe were individually dissected and ligated before removal of the liver parenchyma, thereby decreasing the probability of bleeding in the remnant liver stump. Furthermore, an end-to-side vessel anastomosis between the common hepatic artery and the enlarged proper hepatic artery was introduced to re-arterialize the hepatic artery. By using this end-to-side vessel anastomosis technique, the diameter of the anastomosis was enlarged, thereby decreasing the difficulty of hand suture and maintaining a high rate of anastomotic patency. Moreover, the cuff anastomosis of the infrahepatic vena cava was slightly modified. A section of circumferential liver parenchyma around the vena cava of a recipient was preserved during cuff anastomosis to maintain the three-dimensional shape of the vascular lumen. This section of liver parenchyma was removed after completing the anastomosis. With this modification, the step involving placement of stay sutures was omitted, thereby further shortening the cuff anastomosis time. By using this protocol of rat PLTx, a low liver enzyme level, an intact liver lobular architecture and a high survival rate were achieved after microsurgery.

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Here, a protocol involving re-arterialized rat partial liver transplantation is presented. Specifically, 70% liver was resected in vivo by using an updated technique of vessel-oriented hepatectomy. The hepatic artery was reconstructed in an end-to-side manner. The cuff technique was modified to shorten the anastomosis time of the infrahepatic vena cava.

Re-artérialisé Transplantation de foie partielle de Rat in vivo axée sur le navire 70 % hépatectomie

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. ...

Development of a Novel Task-oriented Rehabilitation Program using a Bimanual Exoskeleton Robotic Hand

A robot-assisted hand is used for the rehabilitation of patients with impaired upper limb function, particularly for stroke patients with a loss of motor control. However, it is unclear how conventional occupational training strategies can be applied to the use of rehabilitation robots. Novel robotic technologies and occupational therapy concepts are used to develop a protocol that allows patients with impaired upper limb function to grasp objects using their affected hand through a variety of pinching and grasping functions. To conduct this appropriately, we used five types of objects: a peg, a rectangular cube, a cube, a ball, and a cylindrical bar. We also equipped the patients with a robotic hand, the Mirror Hand, an exoskeleton&#160;hand that is fitted to the subject&#8217;s affected hand and follows the movement of the sensor glove fitted to their unaffected hand (bimanual movement training (BMT)). This study had two stages. Three healthy subjects were first recruited to test the feasibility and acceptability of the training program. Three patients with hand dysfunction caused by stroke were then recruited to confirm the feasibility and acceptability of the training program, which was conducted on 3 consecutive days. On each day, the patient was monitored during 5 min of movement in a passive range of motion, 5 min of robot-assisted bimanual movement, and task-oriented training using the five objects. The results showed that both healthy subjects and subjects who had suffered a stroke in conjunction with the robotic hand could successfully grasp the objects. Both healthy subjects and those who had suffered a stroke performed well with the robot-assisted task-oriented training program in terms of feasibility and acceptability.

This study reports the development of a novel robot-assisted task-oriented program for hand rehabilitation. The developmental process consists of experiments using both healthy subjects and subjects who have had a stroke and suffered from subsequent motor control dysfunction.

Élaboration d’un nouveau programme de réadaptation axé sur les tâches à l’aide d’une main robotique bimanuale exosquelette

A robot-assisted hand is used for the rehabilitation of patients with impaired upper limb function, particularly for stroke patients with a loss of motor ...