Training in Neurovascular Intervention Usefulness of in-Vitro Model and Clinical Practice

We introduce our training tools and system of neurovascular intervention. An in vitro cerebral vascular model was used for the young residents to understand the basic interventional techniques and devices. The model included several vascular lesions such as cerebral aneurysm, dural arterio-venous fistula, or carotid artery stenosis. Endovascular procedures in the model were performed under fluoroscopic or direct visual control, and consecutive haemodynamic changes were visualized by using digital subtraction angiography and direct observation. Thus, traineess could have an easy understanding of clinical conditions. New medical devices, such as platinum coils, were successfully implanted in the model under stable conditions. After the initial training using vascular model, the residents had started clinical experiences under the control of senior surgeons. Although it is difficult to describe usefulness of our clinical training, we believe that we provide enough good quality and quantity of clinical cases to the residents. Because our endovascular team has recently had 150–200 interventional procedures every year, one resident can have experienced more than 100 cases per year. The qualification of a Board Certified Specialist of the Japanese Society of Intravascular Neurosurgery (JSIN) requires that the applicant must have experienced more than 100 cases for four years. So our residents can have enough case materials to qualify the board examination.

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Sensitivity and specificity of arthroscopic estimation of positive and negative radio-ulnar incongruence in dogs

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-08-12-0125 ◽

2009 ◽

Vol 22 (06) ◽

pp. 437-441. ◽

Cited By ~ 14

Author(s):

H. Werner ◽

V. Grevel ◽

G. Oechtering ◽

P. Böttcher ◽

P. Winkels

Keyword(s):

Sensitivity And Specificity ◽

Elbow Joint ◽

In Vitro Model ◽

Treatment Plan ◽

Accurate Estimation ◽

Elbow Dysplasia ◽

Random Manner ◽

Vitro Model ◽

Clinical Conditions

Summary Objectives: To determine the sensitivity and specificity of arthroscopic estimation of positive and negative radio-ulnar incongruence (RUI) in the canine elbow joint. Methods: Experimental radial shortening and lengthening by 1 and 2 mm increments were performed in nine right elbow joints, extending an established surgical in vitro model of RUI. Arthroscopic estimation of each artificially produced radio-ulnar joint conformation (RUJC) was done using a graduated hook probe. A total of 72 RUJC were blindly evaluated in a random manner by an independent investigator and estimated in 1 mm increments (-2, -1, 0, +1, +2). Results: The sensitivity for identification of an incongruent joint was 0.98 (95% CI: 0.90 to 0.99). The specificity for identification of a congruent joint was 0.89 (95% CI: 0.65 to 0.98). Analysing the data only in respect to a congruent joint versus one with a shortened radius (positive RUI) resulted in a sensitivity of 0.96 (95% CI: 0.80 to 0.99) and a specificity of 1.00 (95% CI: 0.92 to 1.00). Clinical significance: Accurate estimation of RUI in dogs affected by elbow dysplasia might improve functional outcome and prevent osteoarthritis when corrective or modifying osteotomies are being considered as part of the treatment plan. Arthroscopy has been shown to be highly accurate and precise in detecting both positive and negative RUI in vitro. However, its diagnostic strength under clinical conditions still has to be proven.

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A patient-specific intracranial aneurysm model with endothelial lining: a novel in vitro approach to bridge the gap between biology and flow dynamics

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2017-013087 ◽

2017 ◽

Vol 10 (3) ◽

pp. 306-309 ◽

Cited By ~ 23

Author(s):

Naoki Kaneko ◽

Toshihiro Mashiko ◽

Katsunari Namba ◽

Satoshi Tateshima ◽

Eiju Watanabe ◽

...

Keyword(s):

Endothelial Cells ◽

In Vitro Model ◽

Patient Specific ◽

Parent Artery ◽

Complex Flow ◽

Endothelial Lining ◽

Vascular Model ◽

Vitro Model ◽

Aneurysm Model

ObjectivesTo develop an in vitro model for studying the biological effect of complex-flow stress on endothelial cells in three-dimensional (3D) patient-specific vascular geometry.Materials and methodsA vessel replica was fabricated with polydimethylsiloxanes using 3D printing technology from vascular image data acquired by rotational angiography. The vascular model was coated with fibronectin and immersed in a tube filled with a cell suspension of endothelium, and then cultured while being slowly rotated in three dimensions. Culture medium with viscosity was perfused in the circulation with the endothelialized vascular model. A computational fluid dynamics (CFD) study was conducted using perfusion conditions used in the flow experiment. The morphology of endothelial cells was observed under a confocal microscope.ResultsThe CFD study showed low wall shear stress and circulating flow in the apex of the basilar tip aneurysm, with linear flow in the parent artery. Confocal imaging demonstrated that the inner surface of the vascular model was evenly covered with monolayer endothelial cells. After 24 h of flow circulation, endothelial cells in the parent artery exhibited a spindle shape and aligned with the flow direction. In contrast, endothelial cells in the aneurysmal apex were irregular in shape and size.ConclusionsA geometrically realistic intracranial aneurysm model with live endothelial lining was successfully developed. This in vitro model enables a new research approach combining study of the biological impact of complex flow on endothelial cells with CFD analysis and patient information, including the presence of aneurysmal growth or rupture.

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Physiological and Morphological Characterization of Organotypic Cocultures of the Chick Forebrain Area MNH and its Main Input Area DMA/DMP

Neural Plasticity ◽

10.1155/np.2001.219 ◽

2001 ◽

Vol 8 (4) ◽

pp. 219-240 ◽

Cited By ~ 2

Author(s):

Heike Endepols ◽

Julia Jungnickel ◽

Katharina Braun

Keyword(s):

Input Resistance ◽

Morphological Characterization ◽

Inhibitory Neurons ◽

High Frequency Stimulation ◽

Electrophysiological Properties ◽

Stable Conditions ◽

Frequency Stimulation ◽

Vitro Model ◽

Main Input

Cocultures of the learning-relevant forebrain region mediorostrai neostriatum and hyperstriatum ventrale (MNH) and its main glutamatergic input area nucleus dorsomedialis anterior thalami/posterior thalami were morphologically and physiologically characterized. Synaptic contacts of thalamic fibers were lightand electron-microscopically detected on MNH neurons by applying the fluorescence tracer DiI-C18(3) into the thalamus part of the coculture. Most thalamic synapses on MNH neurons were symmetric and located on dendritic shafts, but no correlation between Gray-type ultrastructure and dendritic localization was found. Using intraceilular current clamp recordings, we found that the electrophysiological properties, such as input resistance, time constant, action potential threshold, amplitude, and duration of MNH neurons, remain stable for over 30 days in vitro. Pharmacological blockade experiments revealed glutamate as the main neurotransmitter of thalamic synapses on MNH neurons, which were also found on inhibitory neurons. High frequency stimulation of thalamic inputs evoked synaptic potentiation in22%of MNH neurons. The results indicate that DMA/DMP-MNH cocultures, which can be maintained under stable conditions for at least 4 weeks, provide an attractive in vitro model for investigating synaptic plasticity in the avian brain.

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An in vitro model for investigation of vitamin A effects on wound healing

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000692 ◽

2021 ◽

pp. 1-6

Author(s):

Hoda Keshmiri Neghab ◽

Mohammad Hasan Soheilifar ◽

Gholamreza Esmaeeli Djavid

Keyword(s):

Wound Healing ◽

Endothelial Cell ◽

Vitamin A ◽

In Vitro Model ◽

Cellular Proliferation ◽

Endothelial Cell Migration ◽

Normal Fibroblast ◽

Anti Inflammatory ◽

Vitro Model

Abstract. Wound healing consists of a series of highly orderly overlapping processes characterized by hemostasis, inflammation, proliferation, and remodeling. Prolongation or interruption in each phase can lead to delayed wound healing or a non-healing chronic wound. Vitamin A is a crucial nutrient that is most beneficial for the health of the skin. The present study was undertaken to determine the effect of vitamin A on regeneration, angiogenesis, and inflammation characteristics in an in vitro model system during wound healing. For this purpose, mouse skin normal fibroblast (L929), human umbilical vein endothelial cell (HUVEC), and monocyte/macrophage-like cell line (RAW 264.7) were considered to evaluate proliferation, angiogenesis, and anti-inﬂammatory responses, respectively. Vitamin A (0.1–5 μM) increased cellular proliferation of L929 and HUVEC (p < 0.05). Similarly, it stimulated angiogenesis by promoting endothelial cell migration up to approximately 4 fold and interestingly tube formation up to 8.5 fold (p < 0.01). Furthermore, vitamin A treatment was shown to decrease the level of nitric oxide production in a dose-dependent effect (p < 0.05), exhibiting the anti-inflammatory property of vitamin A in accelerating wound healing. These results may reveal the therapeutic potential of vitamin A in diabetic wound healing by stimulating regeneration, angiogenesis, and anti-inﬂammation responses.

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