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1.
Artículo en Inglés | MEDLINE | ID: mdl-39370493

RESUMEN

PURPOSE: Teleoperated Interventional Robotic systems (TIRs) are developed to reduce radiation exposure and physical stress of the physicians and enhance device manipulation accuracy and stability. Nevertheless, TIRs are not widely adopted, partly due to the lack of intuitive control interfaces. Current TIR interfaces like joysticks, keyboards, and touchscreens differ significantly from traditional manual techniques, resulting in a shallow, longer learning curve. To this end, this research introduces a novel control mechanism for intuitive operation and seamless adoption of TIRs. METHODS: An off-the-shelf medical torque device augmented with a micro-electromagnetic tracker was proposed as the control interface to preserve the tactile sensation and muscle memory integral to interventionalists' proficiency. The control inputs to drive the TIR were extracted via real-time motion mapping of the interface. To verify the efficacy of the proposed control mechanism to accurately operate the TIR, evaluation experiments using industrial grade encoders were conducted. RESULTS: A mean tracking error of 0.32 ± 0.12 mm in linear and 0.54 ± 0.07° in angular direction were achieved. The time lag in tracking was found to be 125 ms on average using pade approximation. Ergonomically, the developed control interface is 3.5 mm diametrically larger, and 4.5 g. heavier compared to traditional torque devices. CONCLUSION: With uncanny resemblance to traditional torque devices while maintaining results comparable to state-of-the-art commercially available TIRs, this research successfully provides an intuitive control interface for potential wider clinical adoption of robot-assisted interventions.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39231067

RESUMEN

SIGNIFICANCE: Research on the conditions under which electronic cigarette (EC) use produces a net reduction in the population harm attributable to combusted cigarette (CC) use requires the triangulation of information from cohort(s) of smokers, non-smokers, EC users, and dual-users of all varieties. MATERIALS AND METHODS: This project utilizes data from the All of Us Research Program to contrast a panel of wellness and disease-risk indicators across a range of self-reported tobacco-use profiles, including smokers, current, and former EC users. This article focuses on the tobacco use history and current tobacco use status among All of Us participants enrolled between May 2017 and February 2023 (Registered Controlled Tier Curated Data Repository [CDR] v7). RESULTS: The present analytic sample included an unweighted total of N = 412 211 individuals with information on ever-use of both CC and EC. Among them, 155 901 individuals have a history of CC use, with 65 206 identified as current smokers. EC usage is reported by 64 002 individuals, with 16 619 being current users. Model predicted analyses identified distinct patterns in CC and EC usage across demographic and socioeconomic variables, with younger ages favoring ECs. DISCUSSION: Age was observed to significantly affect EC usage, and gender differences reveal that males were significantly more likely to use CC and/or EC than females or African Americans of any gender. Higher educational achievement and income were associated with lower use of both CC and EC, while lower levels of mental health were observed to increase the likelihood of using CC and EC products. CONCLUSION: Findings suggest the potential for the All of Us Research Program for investigation of causal factors driving both behavioral use transitions and cessation outcomes.

3.
Sci Rep ; 14(1): 392, 2024 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-38172209

RESUMEN

The pathogenesis of Acute-on-chronic liver failure (ACLF) involves several forms of cell death, such as pyroptosis, apoptosis, and necroptosis, which consist of PANoptosis. To explore PANoptosis as a regulated cell death pathway in ACLF. Firstly, a bioinformatic strategy was used to observe the role of the PANoptosis pathway in ACLF and identify differentially expressed genes related to PANoptosis. Enrichment analysis showed that PANoptosis-related pathways were up-regulated in ACLF. We screened out BAX from the intersection of pyroptosis, apoptosis, necroptosis, and DEGs. Secondly, we screened articles from literature databases related to PANoptosis and liver failure, and specific forms of PANoptosis were reported in different experimental models in vitro and in vivo. Secondly, we established a model of ACLF using carbon tetrachloride-induced liver fibrosis, followed by D-galactosamine and lipopolysaccharide joint acute attacks. A substantial release of inflammatory factors(IL-6, IL-18, TNFα, and IFNγ) and the key proteins of PANoptosis (NLRP3, CASP1, GSDMD, BAX, CASP8, CASP3, CASP7, and MLKL) were detected independently in the ACLF rats. Finally, we found that combining TNF-α/INF-γ inflammatory cytokines could induce L02 cells PANoptosis. Our study highlighted the potential role of ACLF and helps drug discovery targeting PANoptosis in the future.


Asunto(s)
Insuficiencia Hepática Crónica Agudizada , Ratas , Animales , Insuficiencia Hepática Crónica Agudizada/metabolismo , Proteína X Asociada a bcl-2 , Citocinas/metabolismo , Cirrosis Hepática , Factor de Necrosis Tumoral alfa/metabolismo , Apoptosis
4.
J Ultrasound Med ; 41(11): 2755-2766, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35170801

RESUMEN

OBJECTIVES: Ultrasound is useful in predicting arteriovenous fistula (AVF) maturation, which is essential for hemodialysis in end-stage renal disease patients. We developed ultrasound software that measures circumferential vessel wall strain (distensibility) using conventional ultrasound Digital Imaging and Communications in Medicine (DICOM) data. We evaluated user-induced variability in measurement of arterial wall distensibility and upon finding considerable variation we developed and tested 2 methods for semiautomated measurement. METHODS: Ultrasound scanning of arteries of 10 subjects scheduled for AVF surgery were performed. The top and bottom of the vessel wall were tracked using the Kanade-Lucas-Tomasi (KLT) feature-tracking algorithm over the stack of images in the DICOM cine loops. The wall distensibility was calculated from the change of vessel diameter over time. Two semiautomated methods were used for comparison. RESULTS: The location of points selected by users for the cine loops varied significantly, with a maximum spread of up to 120 pixels (7.8 mm) for the top and up to 140 pixels (9.1 mm) for the bottom of the vessel wall. This variation in users' point selection contributed to the variation in distensibility measurements (ranging from 5.63 to 41.04%). Both semiautomated methods substantially reduced variation and were highly correlated with the median distensibility values obtained by the 10 users. CONCLUSIONS: Minimizing user-induced variation by standardizing point selection will increase reproducibility and reliability of distensibility measurements. Our recent semiautomated software may help expand use in clinical studies to better understand the role of vascular wall compliance in predicting the maturation of fistulas.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico , Humanos , Reproducibilidad de los Resultados , Diálisis Renal/métodos , Programas Informáticos
5.
ASAIO J ; 68(1): 112-121, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34380948

RESUMEN

This study presents an edge detection and speckle tracking (EDST) based algorithm to calculate distensibility as percentage of change of vessel diameter during cardiac cycles. Canny edge detector, Vandermonde matrix representation, Kanade Lucas Tomasi algorithm with pyramidal segmentation, and penalized least squares technique identifies the vessel lumen edge, track the vessel diameter, detrend the signal and find peaks and valleys when the vessel is fully distended or contracted. An upper extremity artery from 10 patients underwent an ultrasound examination as part of preoperative evaluation before arteriovenous fistula surgery. Three studies were performed to evaluate EDST with automatic peak and valley selection versus manual speckle selection of expert users using manual peak and valley selection. Results demonstrate the effectiveness of the proposed methodology, to obtain comparable results as those obtained by expert-users, and considerably reducing the variability associated with external factors such as excessive motion, fluctuations in stroke volume, beat-to-beat blood pressure changes, breathing cycles, and arm-transducer pressure.


Asunto(s)
Algoritmos , Derivación Arteriovenosa Quirúrgica , Arterias Carótidas/diagnóstico por imagen , Humanos , Movimiento (Física) , Ultrasonografía
6.
J Vasc Access ; 23(2): 304-308, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32985326

RESUMEN

We used novel open source software, based on an ultrasound speckle tracking algorithm, to examine the distensibility of the vessel wall of the inflow artery, anastomosis, and outflow vein before and after two procedures. An 83-year-old white man with a poorly maturing radio-cephalic fistula received an angioplasty at the anastomosis followed by branch ligation 28 days later. Duplex Doppler measurements corroborated the blood flow related changes anticipated from the interventions. The experimental distensibility results showed that it is technically feasible to measure subtle vessel wall motion changes with high resolution (sub-millimeter) using standard Digital Imaging and Communications in Medicine (DICOM) ultrasound data, which are readily available on conventional ultrasound scanners. While this methodology was originally developed using high resolution radiofrequency from ultrasound data, the goal of this study was to use DICOM data, which makes this technology accessible to a wide range of users.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Fístula , Anciano de 80 o más Años , Angioplastia , Derivación Arteriovenosa Quirúrgica/efectos adversos , Derivación Arteriovenosa Quirúrgica/métodos , Humanos , Masculino , Diálisis Renal/métodos , Programas Informáticos , Resultado del Tratamiento , Grado de Desobstrucción Vascular
7.
J Neurosurg ; 134(3): 1190-1197, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32244204

RESUMEN

OBJECTIVE: The development of new endovascular technologies and techniques for mechanical thrombectomy in stroke has greatly relied on benchtop simulators. This paper presents an affordable, versatile, and realistic benchtop simulation model for stroke. METHODS: A test bed for embolic occlusion of cerebrovascular arteries and mechanical thrombectomy was developed with 3D-printed and commercially available cerebrovascular phantoms, a customized hydraulic system to generate physiological flow rate and pressure, and 2 types of embolus analogs (elastic and fragment-prone) capable of causing embolic occlusions under physiological flow. RESULTS: The test bed was highly versatile and allowed realistic, radiation-free mechanical thrombectomy for stroke due to large-vessel occlusion with rapid exchange of geometries and phantom types. Of the transparent cerebrovascular phantoms tested, the 3D-printed phantom was the easiest to manufacture, the glass model offered the best visibility of the interaction between embolus and thrombectomy device, and the flexible model most accurately mimicked the endovascular system during device navigation. None of the phantoms modeled branches smaller than 1 mm or perforating arteries, and none underwent realistic deformation or luminal collapse from device manipulation or vacuum. The hydraulic system created physiological flow rate and pressure leading to iatrogenic embolization during thrombectomy in all phantoms. Embolus analogs with known fabrication technique, structure, and tensile strength were introduced and consistently occluded the middle cerebral artery bifurcation under physiological flow, and their interaction with the device was accurately visualized. CONCLUSIONS: The test bed presented in this study is a low-cost, comprehensive, realistic, and versatile platform that enabled high-quality analysis of embolus-device interaction in multiple cerebrovascular phantoms and embolus analogs.


Asunto(s)
Procedimientos Endovasculares/instrumentación , Diseño de Equipo/métodos , Embolia Intracraneal/cirugía , Investigación , Accidente Cerebrovascular/cirugía , Trombectomía/instrumentación , Trombectomía/métodos , Anciano , Circulación Cerebrovascular , Embolia/patología , Embolia/cirugía , Procedimientos Endovasculares/economía , Diseño de Equipo/economía , Vidrio , Humanos , Masculino , Persona de Mediana Edad , Modelos Anatómicos , Fantasmas de Imagen , Impresión Tridimensional , Siliconas , Resistencia a la Tracción , Resultado del Tratamiento
8.
Med Eng Phys ; 61: 61-68, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30181022

RESUMEN

Synthetic bones made of polyurethane (PU) foams or glass-fiber reinforced epoxy are often used in surgical training, planning, and tool analysis, but these materials cannot be 3D printed for a patient-specific design. This paper introduces a new type of bone-mimicking material made by the binder jetting technology and a post-strengthening process with epoxy, namely 3D polymer-infiltrated composite (3DPIC). 3DPIC has been previously evaluated by surgeons as a proper alternative to commercial synthetic bones, but no quantitative testing data is available. Therefore, a series of experiments are conducted in this study to verify the use of 3DPIC. The first part of experiments includes the measurement of mechanical properties using the four-point bending and the measurement of thermal properties. The second part of experiments is to test drilling haptic and thermal responses of 3DPIC as compared to the cortical bone. The results show that 3DPIC has a comparable elastic modulus but a lower strength than the cortical bone. 3DPIC can produce realistic drilling force and torque as well as representative temperature change in drilling operations, but the bone debris tends to be more ductile and continuous than that of the cortical bone. Applications and limitations of 3DPIC are discussed based on these results.


Asunto(s)
Hueso Cortical/cirugía , Fenómenos Mecánicos , Procedimientos Ortopédicos , Impresión Tridimensional , Temperatura , Ensayo de Materiales
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