RESUMO
Cellular form and function emerge from complex mechanochemical systems within the cytoplasm. Currently, no systematic strategy exists to infer large-scale physical properties of a cell from its molecular components. This is an obstacle to understanding processes such as cell adhesion and migration. Here, we develop a data-driven modeling pipeline to learn the mechanical behavior of adherent cells. We first train neural networks to predict cellular forces from images of cytoskeletal proteins. Strikingly, experimental images of a single focal adhesion (FA) protein, such as zyxin, are sufficient to predict forces and can generalize to unseen biological regimes. Using this observation, we develop two approaches-one constrained by physics and the other agnostic-to construct data-driven continuum models of cellular forces. Both reveal how cellular forces are encoded by two distinct length scales. Beyond adherent cell mechanics, our work serves as a case study for integrating neural networks into predictive models for cell biology.
Assuntos
Proteínas do Citoesqueleto , Aprendizado de Máquina , Adesão Celular , Citoplasma/metabolismo , Proteínas do Citoesqueleto/metabolismo , Adesões Focais/metabolismo , Modelos BiológicosRESUMO
Cells continuously sense external forces from their microenvironment, the extracellular matrix (ECM). In turn, they generate contractile forces, which stiffen and remodel this matrix. Although this bidirectional mechanical exchange is crucial for many cell functions, it remains poorly understood. Key challenges are that the majority of available matrices for such studies, either natural or synthetic, are difficult to control or lack biological relevance. Here, we use a synthetic, yet highly biomimetic hydrogel based on polyisocyanide (PIC) polymers to investigate the effects of the fibrous architecture and the nonlinear mechanics on cell-matrix interactions. Live-cell rheology was combined with advanced microscopy-based approaches to understand the mechanisms behind cell-induced matrix stiffening and plastic remodeling. We demonstrate how cell-mediated fiber remodeling and the propagation of fiber displacements are modulated by adjusting the biological and mechanical properties of this material. Moreover, we validate the biological relevance of our results by demonstrating that cellular tractions in PIC gels develop analogously to those in the natural ECM. This study highlights the potential of PIC gels to disentangle complex bidirectional cell-matrix interactions and to improve the design of materials for mechanobiology studies.
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Matriz Extracelular , Hidrogéis , Matriz Extracelular/fisiologia , Comunicação CelularRESUMO
Cell traction force plays a critical role in directing cellular functions, such as proliferation, migration, and differentiation. Current understanding of cell traction force is largely derived from 2D measurements where cells are plated on 2D substrates. However, 2D measurements do not recapitulate a vital aspect of living systems; that is, cells actively remodel their surrounding extracellular matrix (ECM), and the remodeled ECM, in return, can have a profound impact on cell phenotype and traction force generation. This reciprocal adaptivity of living systems is encoded in the material properties of biological gels. In this review, we summarize recent progress in measuring cell traction force for cells embedded within 3D biological gels, with an emphasis on cell-ECM cross talk. We also provide perspectives on tools and techniques that could be adapted to measure cell traction force in complex biochemical and biophysical environments.
Assuntos
Matriz Extracelular , Esferoides Celulares , Humanos , Matriz Extracelular/metabolismo , Esferoides Celulares/citologia , Animais , Movimento Celular , Géis/química , Adesão Celular , Microscopia de Força Atômica/métodos , Análise de Célula Única/métodos , Hidrogéis/químicaRESUMO
SignificanceThe pseudokinase integrin-linked kinase (ILK) is a central component of focal adhesions, cytoplasmic multiprotein complexes that integrate and transduce biochemical and mechanical signals from the extracellular environment into the cell and vice versa. However, the precise molecular functions, particularly the mechanosensory properties of ILK and the significance of retained adenosine triphosphate (ATP) binding, are still unclear. Combining molecular-dynamics simulations with cell biology, we establish a role for ATP binding to pseudokinases. We find that ATP promotes the structural stability of ILK, allosterically influences the interaction between ILK and its binding partner parvin at adhesions, and enhances the mechanoresistance of this complex. On the cellular level, ATP binding facilitates efficient traction force buildup, focal adhesion stabilization, and efficient cell migration.
Assuntos
Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Actomiosina/química , Actomiosina/metabolismo , Regulação Alostérica , Sítios de Ligação , Adesão Celular , Movimento Celular , Estabilidade Enzimática , Adesões Focais , Mecanotransdução Celular , Proteínas dos Microfilamentos/química , Proteínas dos Microfilamentos/metabolismo , Modelos Moleculares , Conformação Molecular , Mutação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteínas Serina-Treonina Quinases/genética , Relação Estrutura-Atividade , Especificidade por SubstratoRESUMO
The cytoskeleton of eukaryotic cells is primarily composed of networks of filamentous proteins, F-actin, microtubules, and intermediate filaments. Interactions among the cytoskeletal components are important in determining cell structure and in regulating cell functions. For example, F-actin and microtubules work together to control cell shape and polarity, while the subcellular organization and transport of vimentin intermediate filament (VIF) networks depend on their interactions with microtubules. However, it is generally thought that F-actin and VIFs form two coexisting but separate networks that are independent due to observed differences in their spatial distribution and functions. In this paper, we present a closer investigation of both the structural and functional interplay between the F-actin and VIF cytoskeletal networks. We characterize the structure of VIFs and F-actin networks within the cell cortex using structured illumination microscopy and cryo-electron tomography. We find that VIFs and F-actin form an interpenetrating network (IPN) with interactions at multiple length scales, and VIFs are integral components of F-actin stress fibers. From measurements of recovery of cell contractility after transient stretching, we find that the IPN structure results in enhanced contractile forces and contributes to cell resilience. Studies of reconstituted networks and dynamic measurements in cells suggest direct and specific associations between VIFs and F-actin. From these results, we conclude that VIFs and F-actin work synergistically, both in their structure and in their function. These results profoundly alter our understanding of the contributions of the components of the cytoskeleton, particularly the interactions between intermediate filaments and F-actin.
Assuntos
Citoplasma/metabolismo , Filamentos Intermediários/metabolismo , Vimentina/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/química , Actinas/metabolismo , Animais , Biopolímeros/metabolismo , Células Cultivadas , Tomografia com Microscopia Eletrônica/métodos , Filamentos Intermediários/química , Camundongos , Vimentina/químicaRESUMO
Podosomes are mechanosensitive protrusive actin structures that are prominent in myeloid cells, and they have been linked to vascular extravasation. Recent studies have suggested that podosomes are hierarchically organized and have coordinated dynamics on the cell scale, which implies that the local force generation by single podosomes can be different from their global combined action. Complementary to previous studies focusing on individual podosomes, here we investigated the cell-wide force generation of podosome-bearing ER-Hoxb8 monocytes. We found that the occurrence of focal tractions accompanied by a cell-wide substrate indentation cannot be explained by summing the forces of single podosomes. Instead, our findings suggest that superimposed contraction on the cell scale gives rise to a buckling mechanism that can explain the measured cell-scale indentation. Specifically, the actomyosin network contraction causes peripheral in-plane substrate tractions, while the accumulated internal stress results in out-of-plane deformation in the central cell region via a buckling instability, producing the cell-scale indentation. Hence, we propose that contraction of the actomyosin network, which connects the podosomes, leads to a substrate indentation that acts in addition to the protrusion forces of individual podosomes. This article has an associated First Person interview with the first author of the paper.
Assuntos
Podossomos , Actomiosina , Extensões da Superfície Celular , Humanos , Monócitos , TraçãoRESUMO
Endothelial cells (ECs) within the vascular system encounter fluid shear stress (FSS). High, laminar FSS promotes vasodilation and anti-inflammatory responses, whereas low or disturbed FSS induces dysfunction and inflammation. However, the adaptation of endothelial cells (ECs) to dynamically changing FSS patterns remains underexplored. Here, by combining traction force microscopy with a custom flow chamber, we examined human umbilical vein endothelial cells adapting their traction during transitions from short-term low shear to long-term high shear stress. We discovered that the initial low FSS elevates the traction by only half of the amount in response to direct high FSS even after flow changes to high FSS. However, in the long term under high FSS, the flow started with low FSS triggers a substantial second rise in traction for over 10 h. In contrast, the flow started directly with high FSS results in a quick traction surge followed by a huge reduction below the baseline traction in <30 min. Importantly, we find that the orientation of traction vectors is steered by initial shear exposure. Using Granger causality analysis, we show that the traction that aligns in the flow direction under direct high FSS functionally causes cell alignment toward the flow direction. However, EC traction that orients perpendicular to the flow that starts with temporary low FSS functionally causes cell orientation perpendicular to the flow. Taken together, our findings elucidate the significant influence of initial short-term low FSS on lasting changes in endothelial traction that induces EC alignment.NEW & NOTEWORTHY In our study, we uncover that preconditioning with low shear stress yields enduring impacts on endothelial cell traction and orientation, persisting even after transitioning to high-shear conditions. Using Granger causality analysis, we demonstrate a functional link between the direction of cell traction and subsequent cellular alignment across varying shear environments.
Assuntos
Células Endoteliais da Veia Umbilical Humana , Estresse Mecânico , Humanos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Cultivadas , Mecanotransdução Celular , Fatores de Tempo , Adesão CelularRESUMO
Tissue development is mediated by a combination of mechanical and biological signals. Currently, there are many reports on biological signals regulating repair. However, insufficient attention is paid to the process of mechanical regulation, especially the active mechanical regulation in vivo, which has not been realized. Herein, a novel dynamically regulated repair system for both in vitro and in vivo applications is developed, which utilizes magnetic nanoparticles as non-contact actuators to activate hydrogels. The magnetic hydrogel can be periodically activated and deformed to different amplitudes by a dynamic magnetic system. An in vitro skin model is used to explore the impact of different dynamic stimuli on cellular mechano-transduction signal activation and cell differentiation. Specifically, the effect of mechanical stimulation on the phenotypic transition of fibroblasts to myofibroblasts is investigated. Furthermore, in vivo results verify that dynamic massage can simulate and enhance the traction effect in skin defects, thereby accelerating the wound healing process by promoting re-epithelialization and mediating dermal contraction.
Assuntos
Bandagens , Massagem , Cicatrização , Animais , Massagem/métodos , Fibroblastos , Humanos , Hidrogéis/química , Diferenciação Celular , Pele , Camundongos , Miofibroblastos/citologiaRESUMO
Strain gradients widely exist in development and physiological activities. The directional movement of cells is essential for proper cell localization, and directional cell migration in responses to gradients of chemicals, rigidity, density, and topography of extracellular matrices have been well-established. However; it is unclear whether strain gradients imposed on cells are sufficient to drive directional cell migration. In this work, a programmable uniaxial cell stretch device is developed that creates controllable strain gradients without changing substrate stiffness or ligand distributions. It is demonstrated that over 60% of the single rat embryonic fibroblasts migrate toward the lower strain side in static and the 0.1 Hz cyclic stretch conditions at ≈4% per mm strain gradients. It is confirmed that such responses are distinct from durotaxis or haptotaxis. Focal adhesion analysis confirms higher rates of contact area and protrusion formation on the lower strain side of the cell. A 2D extended motor-clutch model is developed to demonstrate that the strain-introduced traction force determines integrin fibronectin pairs' catch-release dynamics, which drives such directional migration. Together, these results establish strain gradient as a novel cue to regulate directional cell migration and may provide new insights in development and tissue repairs.
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Quimiotaxia , Matriz Extracelular , Ratos , Animais , Movimento Celular , Adesões Focais , Adesão CelularRESUMO
Microtubules are highly polar structures and are characterized by high anisotropy and stiffness. In neurons, they play a key role in the directional transport of vesicles and organelles. In the neuronal projections called axons, they form parallel bundles, mostly oriented with the plus-end towards the axonal termination. Their physico-chemical properties have recently attracted attention as a potential candidate in sensing, processing and transducing physical signals generated by mechanical forces. Here, we discuss the main evidence supporting the role of microtubules as a signal hub for axon growth in response to a traction force. Applying a tension to the axon appears to stabilize the microtubules, which, in turn, coordinate a modulation of axonal transport, local translation and their cross-talk. We speculate on the possible mechanisms modulating microtubule dynamics under tension, based on evidence collected in neuronal and non-neuronal cell types. However, the fundamental question of the causal relationship between these mechanisms is still elusive because the mechano-sensitive element in this chain has not yet been identified.
Assuntos
Axônios , Microtúbulos , Microtúbulos/metabolismo , Axônios/metabolismo , Neurônios/metabolismoRESUMO
The increase in welding time during the interdiffusion of a pair of non reacting random copolymer melts favors the strength rate of healing at the interface. Furthermore, the diffusion kinetic during the interpenetration of copolymer chains across the interface is strongly dependent on molecular weight. In this paper we perform mesoscopic simulations with realistic coarse grain models to study the autohesion mechanism across the interface between slightly entangled styrene-butadiene random copolymer melts.
RESUMO
It is of great importance to study the detachment/attachment behaviors of cells (cancer cell, immune cell, and epithelial cell), as they are closely related with tumor metastasis, immunoreaction, and tissue development at variety scales. To characterize the detachment/attachment during the interaction between cells and substrate, some researchers proposed using cell traction force (CTF) as the indicator. To date, various strategies have been developed to measure the CTF. However, these methods only realize the measurements of cell passive forces on flat cases. To quantify the active CTF on nonflat surfaces, which can better mimic the in vivo case, we employed elastic hydrogel microspheres as a force sensor. The microspheres were fabricated by microfluidic chips with controllable size and mechanical properties to mimic substrate. Cells were cultured on microsphere and the CTF led to the deformation of microsphere. By detecting the morphology information, the CTF exerted by attached cells can be calculated by the in-house numerical code. Using these microspheres, the CTF of various cells (including tumor cell, immunological cell, and epithelium cell) were successfully obtained on nonflat surfaces with different curvature radii. The proposed method provides a versatile platform to measure the CTF with high precision and to understand the detachment/attachment behaviors during physiology processes.
RESUMO
Cell traction force (CTF) is a kind of active force that is a cell senses external environment and actively applies to the contact matrix which is currently a representative stress in cell-extracellular matrix (ECM) interaction. Studying the distribution and variation of CTF during cell-ECM interaction help to explain the impact of physical factors on cell behaviors from the perspective of mechanobiology. However, most of the strategies of characterizing CTF are still limited by the measurement needs in three-dimensional (3D), quantitative characteristics and in vivo condition. Microsphere stress sensor (MSS) as a new type of technology is capable of realizing the quantitative characterization of CTF in 3D and in vivo. Herein, we employed microfluidic platform to design and fabricate MSS which possesses adjustable fluorescent performances, physical properties, and size ranges for better applicable to different cells (3T3, A549). Focusing on the common tumor cells behaviors (adhesion, spreading, and migration) in the process of metastasis, we chose SH-SY5Y as the representative research object in this work. We calculated CTF with the profile and distribution to demonstrate that the normal and shear stress can determined different cell behaviors. Additionally, CTF can also regulate cell adhesion, spreading, and migration in different cell states. Based on this method, the quantitative characterization of CFT of health and disease cells can be achieved, which further help to study and explore the potential mechanism of cell-ECM interaction.
Assuntos
Matriz Extracelular , Hidrogéis , Microesferas , Humanos , Matriz Extracelular/química , Animais , Hidrogéis/química , Camundongos , Adesão Celular , Linhagem Celular Tumoral , Estresse Mecânico , Movimento CelularRESUMO
In the management of shoulder dystocia, it is often recommended to start with external maneuvers, such as the McRoberts maneuver and suprapubic pressure, followed by internal maneuvers including rotation and posterior arm delivery. However, this sequence is not based on scientific evidence of its success rates, the technical simplicity, or the related complication rates. Hence, this review critically evaluates the success rate, technique, and safety of different maneuvers. Retrospective reviews showed that posterior arm delivery has consistently higher success rates (86.1%) than rotational methods (62.4%) and external maneuvers (56.0%). McRoberts maneuver was thought to be a simple method, however, its mechanism is not clear. Furthermore, McRoberts position still requires subsequent traction on the fetal neck, which presents a risk for brachial plexus injury. The 2 internal maneuvers have anatomic rationales with the aim of rotating the shoulders to the wider oblique pelvic dimension or reducing the shoulder width. The techniques are not more sophisticated and requires the accoucher to insert the correct hand (according to fetal face direction) through the more spacious sacro-posterior region and deep enough to reach the fetal chest or posterior forearm. The performance of rotation and posterior arm delivery can also be integrated and performed using the same hand. Retrospective studies may give a biased view that the internal maneuvers are riskier. First, a less severely impacted shoulder dystocia is more likely to have been managed by external maneuvers, subjecting more difficult cases to internal maneuvers. Second, neonatal injuries were not necessarily caused by the internal maneuvers that led to delivery but could have been caused by the preceding unsuccessful external maneuvers. The procedural safety is not primarily related to the nature of the maneuvers, but to how properly these maneuvers are performed. When all these maneuvers have failed, it is important to consider the reasons for failure otherwise repetition of the maneuver cycle is just a random trial and error. If the posterior axilla is just above the pelvic outlet and reachable, posterior axilla traction using either the accoucher fingers or a sling is a feasible alternative. Its mechanism is not just outward traction but also rotation of the shoulders to the wider oblique pelvic dimension. If the posterior axilla is at a higher sacral level, a sling may be formed with the assistance of a long right-angle forceps, otherwise, more invasive methods such as Zavanelli maneuver, abdominal rescue, or symphysiotomy are the last resorts.
Assuntos
Distocia , Distocia do Ombro , Gravidez , Feminino , Recém-Nascido , Humanos , Distocia do Ombro/terapia , Parto Obstétrico/métodos , Distocia/terapia , Estudos Retrospectivos , OmbroRESUMO
Objective Endoscopic papillectomy(EP) is a minimally invasive treatment for early ampullary tumors. However, the optimal method is unclear. The aim of this study is to explore the efficacy and safety of traction-assisted EP treatments for ampullary early tumors.Methods We retrospective analyzed the patients with ampullary adenoma or early adenocarcinoma underwent endoscopic papillectomy between January 2010 and August 2023, including patient characteristics, lesion size, papilla type, pathological diagnosis and lesion surrounding conditions, en-bloc resection rate, complete resection rate, procedure time, complications, recurrences.Results During the study period, a total of 106 patients with ampullary adenoma or early adenocarcinoma underwent EP. The number of patients in traction group (clip combined with dental floss traction, CDT-EP) and non-traction group (hot snare papillectomy, HSP or endoscopic mucosal resection, EMR) were 45 and 61 respectively. The traction group has a higher en-bloc resection rate and complete resection rate than the non-traction group (92.86% vs. 68.85%, p = 0.003; 90.48% vs. 60.66%, p = 0.001), and the procedure time is slightly shorter[(1.57 ± 1.93)min vs. (1.98 ± 1.76)min, p = 0.039]. The complications and recurrence in the traction group were lower than those in the non-traction group (7.14% vs. 19.72%, p = 0.076; 7.14% vs. 11.78%, p = 0.466), and all complications were successfully treated by endoscopy or conservative medical treatment. There was no statistical difference between the two groups in terms of patient characteristics, papilla type, pathological diagnosis and lesion surrounding conditions (p > 0.050), but there were differences in lesion size[(13 ± 1.09)mm vs. (11 ± 1.65)mm, p = 0.002]. The recurrence rate of the traction group is lower than that of the non-traction group, but the difference is not significant(7.14% vs. 13.11%, p = 0.335), and the non-traction group mainly has early recurrence. Further analysis shows that the size of the lesion, whether en-bloc resection or not, and the method of resection as independent risk factors for incomplete resection (OR = 1.732, p = 0.031; OR = 3.716, p = 0.049; OR = 2.120, p = 0.027).Conclusions CDT- EP, HSP and EMR are all suitable methods for the treatment of ampullary adenoma or early adenocarcinoma. Assisted traction technology can reduce the operation difficulty of large and difficult to expose lesions, thereby improving the efficacy and safety of EP.
Assuntos
Adenocarcinoma , Adenoma , Ampola Hepatopancreática , Neoplasias do Ducto Colédoco , Neoplasias Duodenais , Humanos , Ampola Hepatopancreática/cirurgia , Ampola Hepatopancreática/patologia , Resultado do Tratamento , Tração , Estudos Retrospectivos , Endoscopia Gastrointestinal , Adenocarcinoma/cirurgia , Adenocarcinoma/patologia , Neoplasias Duodenais/patologia , Adenoma/cirurgia , Adenoma/patologia , Neoplasias do Ducto Colédoco/cirurgia , Neoplasias do Ducto Colédoco/patologiaRESUMO
BACKGROUND AND AIM: Endoscopic full-thickness resection (EFTR) is a promising technique in treating gastric submucosal tumors originating from the muscularis propria (SMT-MPs). However, it is challenging without counter-traction. METHODS: A snare was inserted through the forceps channel to grasp the part of the tumor or the mucosa connected to the tumor. The outer sheath and inner wire of snare in vitro were fixed by a pair of hemostatic forceps. The handle of snare was cut off, and the endoscope was pulled out without affecting the traction state of snare. Snare-assisted EFTR (EFTR-S) was then performed with counter-traction. One hundred and four patients with gastric SMT-MPs who received the procedure of EFTR with or without snare traction method were retrospectively analyzed using univariate and multiple regressions, and covariates were adjusted in the multiple analysis. RESULTS: Compared with EFTR group (n = 36), EFTR-S group (n = 68) showed a higher operative success rate (95.6% vs 72.2%, P = 0.001), a lower incidence of intraoperative hemorrhage (4.4% vs 16.7%, P = 0.038) and shorter operative time among operative successes (53.6 ± 16.6 min vs 67.7 ± 33.4 min, P < 0.001). Univariate logistic analysis showed that snare traction represented a significant factor, which could improve operative successful rate (odds ratio, 8.3; 95% confidence interval, 2.1 to 32.7; P = 0.002). Postoperative outcomes and adverse events among operative successes were similar between the two groups. CONCLUSIONS: This novel snare traction method may provide an effective counter-traction and reduce the difficulty of EFTR for gastric SMT-MPs.
Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Gastroscopia/métodos , Tração , Estudos Retrospectivos , Resultado do Tratamento , Neoplasias Gástricas/patologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Mucosa Gástrica/cirurgia , Mucosa Gástrica/patologiaRESUMO
BACKGROUND: Proper traction allows safer and easier endoscopic submucosal dissection; however, single-point traction may not be sufficient. In this study we assessed the safety, efficacy, and feasibility of our newly developed multipoint traction device. METHODS: During an ex vivo study using a Konjac training model, two experts and two trainees resected 80 mock lesions of 20-mm diameter by performing endoscopic submucosal dissection with and without multipoint traction. The primary outcome was the success rate of the procedure involving traction. The secondary outcomes were the submucosal dissection time, dissection speed, and perforation during endoscopic submucosal dissection. During the in vivo study, to clarify the initial clinical outcomes, we used data from the electronic medical record of patients at our institution who underwent gastric and colorectal endoscopic submucosal dissection, which was performed by experts with our newly developed multipoint traction device, from March to December 2022. RESULTS: The ex vivo study indicated that all traction procedures were successful. Higher resection speeds were observed with endoscopic submucosal dissection with traction than without traction (P < 0.001). Perforations were not observed. During the first in vivo clinical study, traction was feasible during 20 gastric and colorectal endoscopic submucosal dissection procedures. No adverse events occurred. CONCLUSIONS: Our multitraction device can increase the submucosal dissection speed and simplify endoscopic submucosal dissection techniques, thus safely reducing technical challenges. The application of this device for endoscopic submucosal dissection could lead to safer and more efficient procedures. Clinical registration UMIN Clinical Trials Registry, Japan (registration number UMIN000053384).
Assuntos
Ressecção Endoscópica de Mucosa , Tração , Humanos , Ressecção Endoscópica de Mucosa/métodos , Ressecção Endoscópica de Mucosa/instrumentação , Tração/instrumentação , Tração/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos de Viabilidade , Idoso , Neoplasias Colorretais/cirurgia , Desenho de Equipamento , Mucosa Gástrica/cirurgia , Neoplasias Gástricas/cirurgiaRESUMO
PURPOSE: In vesicourethral anastomosis (VUA), which is part of robot-assisted radical prostatectomy, surgeons must proceed carefully to avoid urethral damage. We developed and evaluated a VUA bench-top model that can measure the traction force on the urethra during robotic surgery. MATERIALS AND METHODS: The VUA model included the urethra, bladder, pelvic bones, and a small force sensor that was capable of measuring the traction force on the urethra. Eight skilled and eight novice urologists performed a VUA task in robotic surgery. The skilled surgeons assessed the model's realism and usefulness as a training tool using a 5-point Likert scale. The evaluation items [task time, maximum force, force volume, and length of time that specific excessive forces were applied to the urethra (2, 3, 4, and ≥ 5 N)] were compared between the skilled and novice surgeons using the Mann-Whitney U test. Measurements were conducted in four directions with respect to the maximum force on the urethra: 11-1, 2-4, 5-7, and 8-10 o'clock. RESULTS: The quality of the model was scored 3.7 to 4.9 points for all 16 items in 4 domains except for "Usefulness compared with animal models." There were differences in the task time and almost all force parameters between the skilled and novice surgeons. CONCLUSION: We developed a relatively high-quality VUA bench-top model that measures traction force on the urethra, and we have revealed differences in the forces of action on the urethra in two groups of surgeons with different skill levels.
Assuntos
Anastomose Cirúrgica , Procedimentos Cirúrgicos Robóticos , Uretra , Bexiga Urinária , Uretra/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Anastomose Cirúrgica/métodos , Humanos , Bexiga Urinária/cirurgia , Masculino , Prostatectomia/métodos , Modelos Anatômicos , Tração , Competência ClínicaRESUMO
BACKGROUND: Gastric endoscopic submucosal dissection (ESD) for lesions located on the greater curvature of the upper and middle (U/M) third of the stomach remains challenging, even for experienced endoscopists. Accordingly, we have developed a novel traction technique, termed the outside-lesion clip-thread method (O-CTM). In this method, a clip thread is attached to the healthy mucosa outside the circumferential incision line, and traction is applied to bring the scope and lesion into proximity for ESD. Here, we assessed the efficacy of ESD using the O-CTM compared to ESD without the O-CTM. METHODS: We retrospectively reviewed data from 63 consecutive patients who underwent gastric ESD for 63 lesions located on the greater curvature of the U/M third of the stomach between September 2015 and April 2024. The primary outcome was the operation time, and secondary outcomes were resection speed, en bloc resection, R0 resection and complications in the O-CTM and without O-CTM ESD groups. RESULTS: Of the 63 included lesions, 37 were resected without the O-CTM between September 2015 and June 2022 (without O-CTM group), and 26 lesions were resected using the O-CTM between July 2022 and April 2024 (O-CTM group). The O-CTM group had significantly shorter operation times (40 min vs. 77 min, p = 0.01) than the without O-CTM group. The resection speed was also significantly faster (20.1 mm2/min vs. 11.3 mm2/min, p = 0.02). No significant differences in en bloc resection rate, R0 resection rate, and complications were observed. CONCLUSIONS: Gastric ESD using O-CTM is beneficial when compared with the ESD without O-CTM in reducing operation time and improving resection speeds for treating lesions located on the greater curvature of the U/M region.
Assuntos
Ressecção Endoscópica de Mucosa , Neoplasias Gástricas , Humanos , Ressecção Endoscópica de Mucosa/métodos , Ressecção Endoscópica de Mucosa/instrumentação , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Feminino , Masculino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Duração da Cirurgia , Mucosa Gástrica/cirurgia , Mucosa Gástrica/patologia , Resultado do Tratamento , Tração/métodos , Gastroscopia/métodos , Instrumentos Cirúrgicos , Idoso de 80 Anos ou maisRESUMO
OBJECTIVE: This study aims to investigate the efficacy and safety of snare traction-assisted endoscopic submucosal dissection (ESD) for the management of circumferential superficial esophageal cancer. METHODS: A total of 68 patients who underwent ESD for circumferential superficial esophageal cancer were included in this study. All the patients were divided into two groups based on whether the snare traction was used or not; the snare traction group (S-ESD, group n = 35) and the control group (C-ESD, group n = 33). RESULTS: There was no significant difference in the size of the resected area between the groups [21.98 (18.30, 27.00) cm2 vs 24.00 (15.28, 30.72) cm2, P = 0.976]. The snare traction group had a shorter dissection time [92.00 (74.00, 121.00) min vs 110.00 (92.50, 137.00) min, P = 0.017] and a faster resection speed [0.28 ± 0.13 cm2/min vs 0.22 ± 0.11cm2/min, P = 0.040] compared to the control group. There were no statistically significant differences between the two groups in terms of hospital stay, cost, en bloc resection rate, R0 resection rate, curative resection rate, bleeding rate, perforation rate, stricture rate, and recurrence rate (P > 0.05). CONCLUSION: Snare traction-assisted ESD is a safe and efficient approach for the treatment of circumferential superficial esophageal cancer. Its advantages includes shorter procedure so the anesthesia requirement, clear operative filed view, improved mucosal dissection efficiency, simple, and easily accessible equipment.