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1.
Biomed Opt Express ; 14(9): 4914-4928, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37791285

RESUMO

This paper describes a framework allowing intraoperative photoacoustic (PA) imaging integrated into minimally invasive surgical systems. PA is an emerging imaging modality that combines the high penetration of ultrasound (US) imaging with high optical contrast. With PA imaging, a surgical robot can provide intraoperative neurovascular guidance to the operating physician, alerting them of the presence of vital substrate anatomy invisible to the naked eye, preventing complications such as hemorrhage and paralysis. Our proposed framework is designed to work with the da Vinci surgical system: real-time PA images produced by the framework are superimposed on the endoscopic video feed with an augmented reality overlay, thus enabling intuitive three-dimensional localization of critical anatomy. To evaluate the accuracy of the proposed framework, we first conducted experimental studies in a phantom with known geometry, which revealed a volumetric reconstruction error of 1.20 ± 0.71 mm. We also conducted an ex vivo study by embedding blood-filled tubes into chicken breast, demonstrating the successful real-time PA-augmented vessel visualization onto the endoscopic view. These results suggest that the proposed framework could provide anatomical and functional feedback to surgeons and it has the potential to be incorporated into robot-assisted minimally invasive surgical procedures.

2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 4843-4848, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086516

RESUMO

There is a large community of people with hand disabilities, and these disabilities can be a barrier to those looking to retain or pursue surgical careers. With the development of surgical robotics technologies, it may be possible to develop user interfaces to accommodate these individuals. This paper proposes a hand-free control method for the gripper of a patient side manipulator (PSM) in the da Vinci surgical system. Using electromyography (EMG) signals, a proportional control method was tested on its ability to grasp a pressure sensor. These preliminary results demonstrate that the user can reliably control the grasping motion of the da Vinci PSM using this system. There is a strong correlation between grasping force and normalized EMG signal (r= 0.874). Moreover, the gripper can generate a step grasping force output when feeding in a generated step signal. The results in this paper demonstrate the system integration of a research EMG system with the da Vinci surgical system and are a step towards developing accessible teleoperation systems for surgeons with disabilities. Hand-free control for remaining degrees of freedom in the PSM is under development using additional input from the motion capture system.


Assuntos
Força da Mão , Robótica , Eletromiografia/métodos , Mãos , Humanos , Extremidade Superior
3.
Animals (Basel) ; 12(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35739914

RESUMO

Sparganosis is a zoonotic parasitic disease caused by the larvae (spargana) of the genus Spirometra, which is widely distributed globally and threatens human health. More than 60 species of Spirometra have already been identified, and over 2000 cases have been reported. This review summarizes the prevalence of humans, frogs, snakes, and other animals with spargana. Furthermore, the infection mode, distribution, and site are summarized and analyzed. We also describe the epidemiology, molecular diagnosis, and other aspects which are of considerable significance to preventing sparganum.

4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 4687-4693, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892259

RESUMO

Lower limb exoskeletons have complex dynamics that mimic human motion. They need to be able to replicate lower limb motion such as walking. The trajectory of the exoskeleton joints and the control signal generated are essential to the system's operation. Current learning from demonstration methods has only been combined with linear quadratic regulators; this limits the applicability of processes since most robotic systems have non-linear dynamics. The Asynchronous Multi-Body Framework simulates the dynamics and allows for real-time control. Eleven gait cycle demonstrations were recorded from volunteers using motion capture and encoded using Task Parameterized Gaussian mixture models. An iterative linear quadratic regulator is used to find an optimal control signal to drive the exoskeleton joints through the desired trajectories. A PD controller is added as a feed-forward control component for unmodeled dynamics and optimized using the Bayesian Information Criterion. We show how the trajectory is learned, and the control signal is optimized by reducing the required bins for learning. The framework presented produces optimal control signals to allow the exoskeleton's legs to follow human motion demonstrations.


Assuntos
Exoesqueleto Energizado , Teorema de Bayes , Fenômenos Biomecânicos , Humanos , Extremidade Inferior , Caminhada
5.
Nat Commun ; 12(1): 3017, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34021145

RESUMO

Extended pluripotent stem (EPS) cells have shown great applicative potentials in generating synthetic embryos, directed differentiation and disease modeling. However, the lack of a xeno-free culture condition has significantly limited their applications. Here, we report a chemically defined and xeno-free culture system for culturing and deriving human EPS cells in vitro. Xeno-free human EPS cells can be long-term and genetically stably maintained in vitro, as well as preserve their embryonic and extraembryonic developmental potentials. Furthermore, the xeno-free culturing system also permits efficient derivation of human EPS cells from human fibroblast through reprogramming. Our study could have broad utility in future applications of human EPS cells in biomedicine.


Assuntos
Técnicas de Cultura de Células/métodos , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Fibroblastos/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Fator 3 de Transcrição de Octâmero
6.
Mol Med Rep ; 20(4): 3131-3139, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31432112

RESUMO

Advanced glycation end products (AGEs) have been reported to serve an important role in the stiffening of cardiac tissues and myocardial cell injury. Serious myocardial cell injury can result in various heart diseases with high mortality. Halofuginone (HF), which possesses marked anti­inflammatory and antifibrotic effects, has recently been applied to inhibit the effects of cardiac stress. The present study aimed to investigate the potential effects of HF and its underlying mechanism in the treatment of AGEs­induced H9C2 cardiomyocyte damage. The western blot results of the present study demonstrated that HF may reduce the expression levels of myocardial injury markers, including myoglobin, creatine kinase MB and cardiac troponin I. In addition, flow cytometric analysis indicated that the production of reactive oxygen species (ROS) was significantly decreased by HF. Additionally, endoplasmic reticulum (ER) stress was suppressed in response to treatment with HF, as observed by low expression levels of ER stress­associated proapoptotic proteins (CCAAT/enhancer­binding protein homologous protein and cleaved caspase­12); overexpression of prosurvival proteins (growth arrest and DNA damage­inducible protein GADD34 and binding immunoglobulin protein) was also reported. Furthermore, the expression levels of microtubule­associated proteins 1A/1B light chain 3B (LC3)II/LC3I and Beclin 1 were elevated, whereas P62 expression levels were reduced following treatment with HF. These findings, together with immunofluorescence staining of LC3, indicated that HF may induce autophagy. Finally, the protective effects of HF on AGEs­treated H9C2 cells were reversed following treatment with the inhibitor 3­methyladenine, as indicated by inhibition of autophagy, and increases in apoptosis, ROS production and the ER stress response. Collectively, the findings of the present study suggested that the protective effects of HF against AGEs­induced myocardial cell injury may be associated with the induction of autophagy and amelioration of ROS­mediated ER stress and apoptosis. These findings may contribute to the development of a novel therapeutic method to inhibit the progression of myocardial cell injury.


Assuntos
Apoptose/efeitos dos fármacos , Morte Celular Autofágica/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Produtos Finais de Glicação Avançada/toxicidade , Miócitos Cardíacos/metabolismo , Piperidinas/farmacologia , Quinazolinonas/farmacologia , Animais , Linhagem Celular , Miócitos Cardíacos/patologia , Ratos
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