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1.
Biomed Pharmacother ; 176: 116771, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38795639

RESUMEN

Anxiety-like conditions can interfere with daily activities as the adaptive mechanism fails to cope with stress. These conditions are often linked with increased oxidative stress, and abrupt neurotransmission and electroencephalography (EEG) wave pattern. Geraniol, a monoterpenoid, has antioxidant and anti-inflammatory activities, as well as brain-calming effects. Therefore, in this study, geraniol was tested for the potential anxiolytic effects in a rat model of anxiety. The rats were exposed to an electric foot shock (1 mA for 1 s) to develop anxiety-like symptoms. Treatment was carried out using geraniol (10 and 30 mg/kg) and the standard diazepam drug. The behavior of the rats was analyzed using the open field test, light-dark test, and social interaction test. Afterward, the rats were decapitated to collect samples for neurochemical and biochemical analyses. The cortical-EEG wave pattern was also obtained. The study revealed that the electric foot shock induced anxiety-like symptoms, increased oxidative stress, and altered hippocampal neurotransmitter levels. The power of low-beta and high-beta was amplified with the increased coupling of delta-beta waves in anxiety group. However, the treatment with geraniol and diazepam normalized cortical-EEG wave pattern and hippocampal serotonin and catecholamines profile which was also reflected by reduced anxious behavior and normalized antioxidant levels. The study reports an anxiolytic potential of geraniol, which can be further explored in future.


Asunto(s)
Monoterpenos Acíclicos , Ansiolíticos , Ansiedad , Conducta Animal , Electroencefalografía , Hipocampo , Estrés Oxidativo , Ratas Wistar , Transmisión Sináptica , Animales , Monoterpenos Acíclicos/farmacología , Estrés Oxidativo/efectos de los fármacos , Ansiedad/tratamiento farmacológico , Masculino , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ansiolíticos/farmacología , Ratas , Transmisión Sináptica/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Electrochoque , Antioxidantes/farmacología , Terpenos/farmacología , Diazepam/farmacología , Modelos Animales de Enfermedad , Ondas Encefálicas/efectos de los fármacos
2.
Int J Comput Assist Radiol Surg ; 17(9): 1569-1577, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35588338

RESUMEN

PURPOSE: Tricuspid valve (TV) interventions face the challenge of imaging the anatomy and tools because of the 'TEE-unfriendly' nature of the TV. In edge-to-edge TV repair, a core step is to position the clip perpendicular to the coaptation gap. In this study, we provide a semi-automated method to localize the VC from Doppler intracardiac echo (ICE) imaging in a tracked 3D space, thus providing a pre-mapped location of the coaptation gap to assist device positioning. METHODS: A magnetically tracked ICE probe with Doppler imaging capabilities is employed in this study for imaging three patient-specific TVs placed in a pulsatile heart phantom. For each of the valves, the ICE probe is positioned to image the maximum regurgitant flow for five cardiac cycles. An algorithm then extracts the regurgitation imaging and computes the exact location of the vena contracta on the image. RESULTS: Across the three pathological, patient-specific valves, the average distance error between the detected VC and the ground truth model is [Formula: see text]mm. For each of the valves, one case represented the outlier where the algorithm misidentified the vena contracta to be near the annulus. In such cases, it is recommended to retake the five-second imaging data. CONCLUSION: This study presented a method for ultrasound-based localization of vena contracta in 3D space. Mapping such anatomical landmarks has the potential to assist with device positioning and to simplify tricuspid valve interventions by providing more contextual information to the interventionalists, thus enhancing their spatial awareness. Additionally, ICE can be used to provide live US and Doppler imaging of the complex TV anatomy throughout the procedure.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Ecocardiografía Tridimensional , Procedimientos Quirúrgicos Cardíacos/métodos , Ecocardiografía Doppler en Color/métodos , Ecocardiografía Tridimensional/métodos , Ecocardiografía Transesofágica/métodos , Humanos , Índice de Severidad de la Enfermedad , Válvula Tricúspide/diagnóstico por imagen , Válvula Tricúspide/cirugía
3.
Ultrasound Med Biol ; 48(7): 1290-1298, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35487839

RESUMEN

Transcatheter cardiovascular interventions have the advantage of patient safety, reduced surgery time and minimal trauma to the patient's body. Transcathether interventions, which are performed percutaneously, are limited by the lack of direct line of sight with the procedural tools and the patient anatomy. Therefore, such interventional procedures rely heavily on image guidance for navigating toward and delivering therapy at the target site. Vascular navigation via the inferior vena cava, from the groin to the heart, is an imperative part of most transcatheter cardiovascular interventions including heart valve repair surgeries and ablation therapy. Traditionally, the inferior vena cava is navigated using fluoroscopic techniques such as venography and computed tomography venography. These X-ray-based techniques can have detrimental effects on the patient as well as the surgical team, causing increased radiation exposure, leading to risk of cancer, fetal defects and eye cataracts. The use of a heavy lead apron has also been reported to cause back pain and spine issues, thus leading to interventionalist's disc disease. We propose the use of a catheter-based ultrasound augmented with electromagnetic tracking technology to generate a vascular roadmap in real time and perform navigation without harmful radiation. In this pilot study, we used spatially tracked intracardiac echocardiography to reconstruct a vessel from a phantom in a 3-D virtual environment. We illustrate how the proposed ultrasound-based navigation will appear in a virtual environment, by navigating a tracked guidewire within the vessels in the phantom without any radiation-based imaging. The geometric accuracy is assessed using a computed tomography scan of the phantom, with a Dice coefficient of 0.79. The average distance between the surfaces of the two models comes out to be 1.7 ± 1.12 mm.


Asunto(s)
Corazón , Cirugía Asistida por Computador , Diseño de Equipo , Humanos , Fantasmas de Imagen , Proyectos Piloto , Ultrasonografía
4.
Pak J Pharm Sci ; 35(1(Supplementary)): 239-245, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35228183

RESUMEN

Geraniol, a component of essential oil, is reported to have various pharmacological properties. The current study was conducted to demonstrate the dose-dependent neurobehavioral effects of geraniol. Rats were divided into 5 groups (n=7), comprising of control and four test groups for different doses of geraniol including 10, 30, 50 and 100 mg/kg. Geraniol was given for 15 days through intraperitoneal route. Following the administration, anxiety-, depression-like behaviors and memory function were evaluated. Extent of oxidative stress in rat's brain was also assessed by determining the levels of malondialdehyde and antioxidant enzymes activity. The present study revealed that low doses of geraniol produced more potent anxiolytic, antidepressant, nootropic, and antioxidant effects as compared to the higher doses. The findings highlight the dual characteristic of geraniol, acting as antioxidant at lower doses while at higher doses it produces pro-oxidant effects. The results are discussed in the context of dual characteristic of antioxidant compounds.


Asunto(s)
Monoterpenos Acíclicos/farmacología , Ansiedad/tratamiento farmacológico , Malondialdehído/sangre , Memoria/efectos de los fármacos , Aceites Volátiles/química , Animales , Conducta Animal/efectos de los fármacos , Encéfalo , Glutatión/metabolismo , Masculino , Ratas , Ratas Wistar
5.
Int J Comput Assist Radiol Surg ; 15(9): 1513-1523, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32524216

RESUMEN

PURPOSE: This work aims to develop a simple, anatomically and haptically realistic vascular phantom, compatible with intravascular and intracardiac ultrasound. The low-cost, dual-layered phantom bridges the gap between traditional wall-only and wall-less phantoms by showing both the vessel wall and surrounding tissue in ultrasound imaging. This phantom can better assist clinical tool training, testing of intravascular devices, blood flow studies, and validation of algorithms for intravascular and intracardiac surgical systems. METHODS: Polyvinyl alcohol cryogel (PVA-c) incorporating a scattering agent was used to obtain vessel and tissue-mimicking materials. Our specific design targeted the inferior vena cava and renal bifurcations which were modelled using CAD software. A custom mould and container were 3D-printed for shaping the desired vessel wall. Three phantoms were prepared by varying both the concentrations of scattering agent as well as the number of freeze-thaw cycles to which the phantom layers were subjected during the manufacturing process. Each phantom was evaluated using ultrasound imaging using the Foresight™ ICE probe. Geometrical validation was provided by comparing CAD design to a CT scan of the phantom. RESULTS: The desired vascular phantom was constructed using 2.5% and 0.05% scattering agent concentration in the vessel and tissue-mimicking layers, respectively. Imaging of the three phantoms showed that increasing the number of freeze-thaw cycles did not significantly enhance the image contrast. Comparison of the US images with their CT equivalents resulted in an average error of 0.9[Formula: see text] for the lumen diameter. CONCLUSION: The phantom is anatomically realistic when imaged with intracardiac ultrasound and provides a smooth lumen for the ultrasound probe and catheter to manoeuvre. The vascular phantom enables validation of intravascular and intracardiac image guidance systems. The simple construction technique also provides a workflow for designing complex, multi-layered arterial phantoms.


Asunto(s)
Diagnóstico por Computador/métodos , Corazón/diagnóstico por imagen , Fantasmas de Imagen , Algoritmos , Arterias , Criogeles , Diseño de Equipo , Humanos , Ensayo de Materiales , Poliésteres , Alcohol Polivinílico , Dispersión de Radiación , Siliconas , Programas Informáticos , Tomografía Computarizada por Rayos X , Ultrasonografía
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