scholarly journals Surgical Robot for Intraluminal Access: An Ex Vivo Feasibility Study

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Ryu Nakadate ◽  
Tsutomu Iwasa ◽  
Shinya Onogi ◽  
Jumpei Arata ◽  
Susumu Oguri ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Ex Vivo ◽  
Early Stage ◽  
Skin Incision ◽  
Robotic System ◽  
Flexible Endoscope ◽  
Surgical Robot ◽  
Energy Devices ◽  
Flexible Devices ◽  
Feasibility Evaluation

Early-stage gastrointestinal cancer is often treated by endoscopic submucosal dissection (ESD) using a flexible endoscope. Compared with conventional percutaneous surgery, ESD is much less invasive and provides a high quality of life for the patient because it does not require a skin incision, and the organ is preserved. However, the operator must be highly skilled because ESD requires using a flexible endoscope with energy devices, which have limited degrees of freedom. To facilitate easier manipulation of these flexible devices, we developed a surgical robot comprising a flexible endoscope and two articulating instruments. The robotic system is based on a conventional flexible endoscope, and an extrapolated motor unit moves the endoscope in all its degrees of freedom. The instruments are thin enough to allow insertion of two instruments into the endoscope channel, and each instrument has a bending section that allows for up–down, right–left, and forward–backward motion. In this study, we performed an ex vivo feasibility evaluation using the proposed robotic system for ESD in a porcine stomach. The procedure was successfully performed by five novice operators without complications. Our findings demonstrated the feasibility of the proposed robotic system and, furthermore, suggest that even operators with limited experience can use this system to perform ESD.

scholarly journals Biomimetic six-axis robots replicate human cardiac papillary muscle motion: pioneering the next generation of biomechanical heart simulator technology

2020 ◽  
Vol 17 (173) ◽  
pp. 20200614
Author(s):  
Annabel M. Imbrie-Moore ◽  
Matthew H. Park ◽  
Michael J. Paulsen ◽  
Mark Sellke ◽  
Rohun Kulkami ◽  
...  
Keyword(s):  
Papillary Muscle ◽  
Degrees Of Freedom ◽  
Ex Vivo ◽  
Robotic System ◽  
Papillary Muscles ◽  
Chordae Tendineae ◽  
Six Degrees Of Freedom ◽  
Reachable Workspace ◽  
Computed Tomography Images ◽  
Force Profile

Papillary muscles serve as attachment points for chordae tendineae which anchor and position mitral valve leaflets for proper coaptation. As the ventricle contracts, the papillary muscles translate and rotate, impacting chordae and leaflet kinematics; this motion can be significantly affected in a diseased heart. In ex vivo heart simulation, an explanted valve is subjected to physiologic conditions and can be adapted to mimic a disease state, thus providing a valuable tool to quantitatively analyse biomechanics and optimize surgical valve repair. However, without the inclusion of papillary muscle motion, current simulators are limited in their ability to accurately replicate cardiac biomechanics. We developed and implemented image-guided papillary muscle (IPM) robots to mimic the precise motion of papillary muscles. The IPM robotic system was designed with six degrees of freedom to fully capture the native motion. Mathematical analysis was used to avoid singularity conditions, and a supercomputing cluster enabled the calculation of the system's reachable workspace. The IPM robots were implemented in our heart simulator with motion prescribed by high-resolution human computed tomography images, revealing that papillary muscle motion significantly impacts the chordae force profile. Our IPM robotic system represents a significant advancement for ex vivo simulation, enabling more reliable cardiac simulations and repair optimizations.

Thrombin Generation Measured Ex Vivo Following Microvasculor Injury Is Increased in SLE Patients with Antiphospholipid-protein Antibodies

1997 ◽  
Vol 78 (04) ◽  
pp. 1173-1177 ◽  
Author(s):  
Jacek Musiał ◽  
Jakub Swadźba ◽  
Miłosz Jankowski ◽  
Marek Grzywacz ◽  
Stanisława Bazan-Socha ◽  
...  
Keyword(s):  
Lupus Erythematosus ◽  
Thrombin Generation ◽  
Ex Vivo ◽  
Skin Incision ◽  
Anticardiolipin Antibodies ◽  
Small Blood Vessel ◽  
Anionic Phospholipids ◽  
Increased Risk ◽  
High Concentrations

SummaryAntiphospholipid-protein antibodies (APA) include lupus-type anticoagulant (LA) and antibodies recognizing complexes of anionic phospholipids (e.g. cardiolipin) and proteins (e.g. prothrombin and (β2-glycoprotein I). The presence of APA is associated with an increased risk of both arterial and venous thrombosis. However, the pathogenic mechanism leading to thrombosis in patients with APA remains unclear. We studied 32 patients with systemic lupus erythematosus (SLE) who were divided into two groups depending on the presence (n = 19) or absence (n = 13) of APA. Healthy volunteers (n = 12) matched by age and sex served as controls. In all subjects LA and IgG class anticardiolipin antibodies (ACA) were determined. Thrombin generation was monitored ex vivo measuring fibrinopeptide A (FPA) and prothrombin fragment F1 + 2 (F1 + 2) in blood emerging from a skin microvasculature injury, collected at 30 second intervals. In subjects with antiphospholipid antibodies mean FPA and F1 + 2 concentrations were signiF1cantly higher at most blood sampling times than in controls. In some SLE patients with APA the process of thrombin generation was clearly disturbed and very high concentrations of F1brinopeptide A were detected already in the F1rst samples collected. Two minutes after skin incision SLE patients without APA produced slightly more FPA, but not F1 + 2, as compared to healthy subjects. Mathematical model applied to analyze the thrombin generation kinetics revealed that APA patients generated signiF1cantly greater amounts of thrombin than healthy controls (p = 0.02 for either marker). In contrast, in the same patients generation of thrombin in recalciF1ed plasma in vitro was delayed pointing to the role of endothelium in the phenomenon studied. In summary, these data show for the F1rst time that in SLE patients with antiphospholipid-protein antibodies thrombin generation after small blood vessel injury is markedly increased. Enhanced thrombin generation might explain thrombotic tendency observed in these patients.

Adenosine Diphosphate (ADP)-Induced ⍺-Granules Release from Platelets of Native Whole Blood Is Reduced by Ticlopidine but Not by Aspirin or Dipyridamole

1986 ◽  
Vol 56 (02) ◽  
pp. 147-150 ◽  
Author(s):  
V Pengo ◽  
M Boschello ◽  
A Marzari ◽  
M Baca ◽  
L Schivazappa ◽  
...  
Keyword(s):  
Whole Blood ◽  
Light Transmission ◽  
Ex Vivo ◽  
Early Stage ◽  
Shape Change ◽  
Adenosine Diphosphate ◽  
Dose Dependent ◽  
Plateletderived Growth Factor ◽  
Platelet Shape

SummaryA brief contact between native whole blood and ADP promotes a dose-dependent release of platelet a-granules without a fall in the platelet number. We assessed the “ex vivo” effect of three widely used antiplatelet drugs, aspirin dipyridamole and ticlopidine, on this system. Aspirin (a single 800 mg dose) and dipyridamole (300 mg/die for four days) had no effect, while ticlopidine (500 mg/die for four days) significantly reduced the a-granules release for an ADP stimulation of 0.4 (p <0.02), 1.2 (p <0.01) and 2 pM (p <0.01). No drug, however, completeley inhibits this early stage of platelet activation. The platelet release of α-granules may be related to platelet shape change of the light transmission aggregometer and may be important “in vivo” by enhancing platelet adhesiveness and by liberating the plateletderived growth factor.

Development of master-slave magnetic anchoring vision robotic system for single-port laparoscopy (SPL) surgery

2018 ◽  
Vol 45 (4) ◽  
pp. 458-468
Author(s):  
Haibo Feng ◽  
Yanwu Zhai ◽  
Yili Fu
Keyword(s):  
Single Port ◽  
Robotic System ◽  
Surgical Robot ◽  
Distribution Analysis ◽  
Robot System ◽  
Content Type ◽  
Blind Area ◽  
Robot Systems ◽  
Single Port Laparoscopy ◽  
And Performance

Purpose Surgical robot systems have been used in single-port laparoscopy (SPL) surgery to improve patient outcomes. This study aims to develop a vision robot system for SPL surgery to effectively improve the visualization of surgical robot systems for relatively complex surgical procedures. Design/methodology/approach In this paper, a new master-slave magnetic anchoring vision robotic system for SPL surgery was proposed. A lighting distribution analysis for the imaging unit of the vision robot was carried out to guarantee illumination uniformity in the workspace during SPL surgery. Moreover, cleaning force for the lens of the camera was measured to assess safety for an abdominal wall, and performance assessment of the system was performed. Findings Extensive experimental results for illumination, control, cleaning force and functionality test have indicated that the proposed system has an excellent performance in providing the visual feedback. Originality/value The main contribution of this paper lies in the development of a magnetic anchoring vision robot system that successfully improves the ability of cleaning the lens and avoiding the blind area in a field of view.

scholarly journals Rationally Designing Simple Rod-Like Amphiphilic NIR-Emissive AIE Probes for Precise In-Vivo Detection of Aβ Fibrils/Plaques at A Super-Early Stage

2021 ◽  
Author(s):  
Yipu Wang ◽  
Dong Mei ◽  
Xinyi Zhang ◽  
Da-Hui Qu ◽  
Ju Mei ◽  
...  
Keyword(s):  
High Performance ◽  
Ex Vivo ◽  
Early Stage ◽  
Signal To Noise Ratio ◽  
High Signal ◽  
In Vivo Detection ◽  
Different Strains ◽  
Aβ Fibrils

With increase of social aging, Alzheimer's disease (AD) has been one of the serious diseases threatening human health. The occurrence of A<i>β </i>fibrils<i> </i>or plaques is recognized as the hallmark of AD.<i> </i>Currently, optical imaging has stood out to be a promising technique for the imaging of A<i>β</i> fibrils/plaques and the diagnosis of AD. However, restricted by their poor blood-brain barrier (BBB) penetrability, short-wavelength excitation and emission, and aggregation-caused quenching (ACQ) effect, the clinically used gold-standard optical probes such as <a>thioflavin</a> T (ThT) and thioflavin S (ThS), are not effective enough in the early diagnosis of AD <i>in vivo</i>. Herein, we put forward an “all-in-one” design principle and demonstrate its feasibility in developing high-performance fluorescent probes which are specific to A<i>β</i> fibrils/plaques and promising for super-early <i>in</i>-<i>vivo</i> diagnosis of AD. As a proof of concept, a simple rod-like amphiphilic NIR fluorescent AIEgen, i.e., AIE-CNPy-AD, is developed by taking the specificity, BBB penetration ability, deep-tissue penetration capacity, high signal-to-noise ratio (SNR) into consideration. AIE-CNPy-AD is constituted by connecting the electron-donating and accepting moieties through single bonds and tagging with a propanesulfonate tail, giving rise to the NIR fluorescence, aggregation-induced emission (AIE) effect, amphiphilicity, and rod-like structure, which in turn result in high binding-affinity and excellent specificity to A<i>β</i> fibrils/plaques, satisfactory ability to penetrate BBB and deep tissues, ultrahigh SNR and sensitivity, and high-fidelity imaging capability. <i>In-vitro, ex-vivo,</i> and <i>in-vivo</i> <a>identifying of A<i>β</i> fibrils/plaques</a> in different strains of mice indicate that AIE-CNPy-AD holds the universality to the detection of A<i>β</i> fibrils/plaques. It is noteworthy that AIE-CNPy-AD is even able to trace the small and sparsely distributed A<i>β</i> fibrils/plaques in very young AD model mice such as 4-month-old APP/PS1 mice which are reported to be the youngest mice to have A<i>β</i> deposits in brains, suggesting its great potential in diagnosis and intervention of AD at a super-early stage.

scholarly journals Freeze-thaw decellularization of the trabecular meshwork in an ex vivo eye perfusion model

2017 ◽  
Author(s):  
Yalong Dang ◽  
Susannah Waxman ◽  
Chao Wang ◽  
Adrianna Jensen ◽  
Ralitsa T Loewen ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Trabecular Meshwork ◽  
Degrees Of Freedom ◽  
Ex Vivo ◽  
Fluorescent Microscopy ◽  
Anterior Segment ◽  
Perfusion Culture ◽  
Suicide Gene ◽  
Control Group ◽  
Freeze Thaw

Objective: Trabecular meshwork (TM) is the primary substrate of outflow resistance in glaucomatous eyes. Repopulating diseased TM with fresh, functional TM cells might represent a novel therapeutic breakthrough. Various decellularized TM scaffolds were developed by ablating existing cells with suicide gene therapy or saponin, but always with incomplete cell removal or dissolve the extracellular matrix. We hypothesized that a chemical-free, freeze-thaw method would be able to produce a fully decellularized TM scaffold for cell transplantation. Materials and Methods: We obtained 24 porcine eyes from a local abattoir, dissected and mounted them in an anterior segment perfusion and pressure transduction system within two hours of sacrifice. After they stabilized for 72 hours, eight eyes each were assigned to freeze-thaw (F) ablation (-80°C×2), to 0.02% saponin (S) treatment, or the control group (C), respectively. The trabecular meshwork was transduced with an eGFP expressing feline immunodeficiency viral (FIV) vector and tracked via fluorescent microscopy to confirm ablation. Following treatment, the eyes were perfused with standard tissue culture medium for 180 hours. We assessed histological changes by hematoxylin and eosin staining. TM cell viability was evaluated with a calcein AM/propidium iodide (PI) assay. We measured IOP and modeled it with a linear mixed effects model using a B-spline function of time with 5 degrees of freedom. Results: F and S experienced a similar IOP reduction by 30% from baseline (P=0.64). IOP reduction of about 30% occurred in F within 24 hours and in S within 48 hours. Live visualization of eGFP demonstrated that F conferred a complete ablation of all TM cells and only a partial ablation in S. Histological analysis confirmed that no TM cells survived in F while the extracellular matrix remained. The viability assay showed very low PI and no calcein staining in F in contrast to numerous PI-labeled dead TM cells and calcein-labeled viable TM cells in S. Conclusion: We developed a rapid TM ablation method that uses cyclic freezing that is free of biological or chemical agents and able to produce a decellularized TM scaffold with preserved TM excellular matrix in an organotypic perfusion culture.

scholarly journals Pilot study of pulmonary arterial branch sealing using energy devices in an ex vivo model

2014 ◽  
Vol 148 (6) ◽  
pp. 3219-3223 ◽  
Author(s):  
Moishe Liberman ◽  
Mohamed Khereba ◽  
Eric Goudie ◽  
Jordan Kazakov ◽  
Vicky Thiffault ◽  
...  
Keyword(s):  
Pilot Study ◽  
Ex Vivo ◽  
Ex Vivo Model ◽  
Energy Devices ◽  
Pulmonary Arterial ◽  
Arterial Branch

scholarly journals Spontaneous Glioblastoma Spheroid Infiltration of Early-Stage Cerebral Organoids Models Brain Tumor Invasion

2018 ◽  
Vol 23 (8) ◽  
pp. 862-868 ◽  
Author(s):  
Bárbara da Silva ◽  
Ryan K. Mathew ◽  
Euan S. Polson ◽  
Jennifer Williams ◽  
Heiko Wurdak
Keyword(s):  
Brain Tumor ◽  
Molecular Mechanisms ◽  
Ex Vivo ◽  
Early Stage ◽  
Brain Parenchyma ◽  
Infiltration Process ◽  
Complete Surgical Resection ◽  
Tumor Phenotype ◽  
Human Gbm ◽  
Tissue Compartments

Organoid methodology provides a platform for the ex vivo investigation of the cellular and molecular mechanisms underlying brain development and disease. The high-grade brain tumor glioblastoma multiforme (GBM) is considered a cancer of unmet clinical need, in part due to GBM cell infiltration into healthy brain parenchyma, making complete surgical resection improbable. Modeling the process of GBM invasion in real time is challenging as it requires both tumor and neural tissue compartments. Here, we demonstrate that human GBM spheroids possess the ability to spontaneously infiltrate early-stage cerebral organoids (eCOs). The resulting formation of hybrid organoids demonstrated an invasive tumor phenotype that was distinct from noncancerous adult neural progenitor (NP) spheroid incorporation into eCOs. These findings provide a basis for the modeling and quantification of the GBM infiltration process using a stem-cell-based organoid approach, and may be used for the identification of anti-GBM invasion strategies.

Abstract 17268: ApoA-I Mimetic Peptide 4F Suppresses the Elevation of Pro-Inflammatory Lipid Mediators in Mouse Models of Inflammatory Bowel Disease

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_1) ◽  
Author(s):  
David Meriwether ◽  
Carmen Volpe ◽  
Victor Grijalva ◽  
Ellen O’Connor ◽  
Nasrin Dorreh ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Mouse Models ◽  
Inflammatory Mediators ◽  
Bowel Disease ◽  
Ex Vivo ◽  
Early Stage ◽  
Lipid Mediators ◽  
Serosal Side ◽  
Ussing Chambers ◽  
Inflammatory Bowel

Introduction: Inflammatory bowel disease (IBD) has been linked to an increased prevalence of early stage vascular disease. ApoA-I mimetic peptides including 4F are potential therapeutic agents for the treatment of inflammatory diseases including atherosclerosis, and their mechanism of action appears localized to the intestine. We have reported that 4F protects against the development of disease in both the piroxicam-accelerated IL10-/- and myeloid COX2-/- mouse models of IBD. Hypothesis: We previously reported that plasma and lesion levels of oxidized products of linoleic and arachidonic acid correlate with disease in mouse models of atherosclerosis, and that 4F protects against disease in these models while inhibiting accumulation of these pro-inflammatory mediators. We thus sought to determine the complete lipid pro-inflammatory mediator profiles of both the COX2- and IL10-dependent models of IBD, while also determining the effect of 4F on the pro-inflammatory lipid profiles. Methods: We developed and validated a LC-ESI-MS/MS method for determining the levels of 40 lipid inflammatory mediators in both intestinal tissue and plasma, and we analyzed the effects of both disease and 4F upon these mediators in both IBD models. We also employed Ussing chambers to investigate ex vivo the direct effect of 4F on the clearance of pro-inflammatory lipid mediators from intestinal explants and serosal-side lipoproteins. Results: Disease in both models correlated with significantly elevated tissue and plasma levels of multiple lipid pro-inflammatory mediators, while the protective effects of 4F correlated with the significant suppression of most of these mediators. Of interest, 4F inhibited the disease dependent increase of 15HETE, 12HETE, 5HETE, 13HODE, LTB4, 6ketoPGF1α, PGF2α, and TXB2 in the COX2-/- model; and 15HETE, 12HETE, 13HODE, LTB4, and LTE4 in the IL10-/- model. Ex vivo, we showed that 4F could directly clear the pro-inflammatory mediators from inflamed intestinal explants, while also mediating their trans-intestinal efflux from serosal-side lipoproteins. Conclusions: 4F appears to protect against IBD in part by inhibiting the accumulation of pro-inflammatory lipid mediators, through a mechanism that involves the intestinal clearance of these mediators from tissue and plasma.

scholarly journals Evaluation of a Balloon-Type Vaginal Endoscope Based on Three-Dimensional Printing Technology for Self-Assessment of Pelvic Organ Prolapse

2020 ◽  
Vol 10 (15) ◽  
pp. 5108
Author(s):  
Myoungjae Jun ◽  
Hieyong Jeong ◽  
Masayuki Endo ◽  
Michiko Kodama ◽  
Yuko Ohno
Keyword(s):  
Pelvic Organ Prolapse ◽  
Early Stage ◽  
Low Cost ◽  
Three Dimensional ◽  
Evaluation Study ◽  
Pelvic Organ ◽  
Self Assessment ◽  
Overweight Women ◽  
Depth Sensors ◽  
Feasibility Evaluation

Pelvic organ prolapse (POP) can occur if the support tissues or the pelvic floor muscles are weakened and damaged. There is increased probability for POP occurrence after childbirth, menopause, or in overweight women. Because the natural history and progression of POP is still unknown, the approaches used to prevent it have not been clear. POP is an uncomfortable condition that affects one every three women. However, most people feel uncomfortable to discuss it. Herein, we conducted a feasibility evaluation study for self-assessment approaches with a vaginal endoscope based on three-dimensional (3D) printing. The proposed endoscope has two parts: (a) rubber material used to cover it for its intended insertion, to avoid direct contact with the walls of the vagina, and (b) two types of sensors at the tip for measurements. The condition inside the vagina was observed with a camera and depth sensors based on the regulation of the amount of air. Arbitrary temporary prolapses from the testbed’s generator enabled us to perceive the location of the problem and symptoms that were regarded as the early stage. As discussed, the low-cost design of the 3D-printed-based vaginal endoscope provides a self-check capability and allows continuous observations that help prevent POP.

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