scholarly journals Vocal Fold Augmentation with Beta Glucan Hydrogel Cross-Linked byγIrradiation for Enhanced Duration of Effect:In VivoAnimal Study

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Youn-Mook Lim ◽  
Bo Hae Kim ◽  
Hee-Bok Kim ◽  
EunJi Park ◽  
Seok-Won Park ◽  
...  

This study explored a novel strategy to restore the vocal gap by using cross-linkedβ-glucan hydrogel byγ-irradiation. An aqueous solution of 5 wt%β-glucan was prepared and cross-linked using60Coγirradiation. Ten nude mice were injected with 0.8 mL of irradiatedβ-glucan on the left back and the same volume of nonirradiatedβ-glucan on the right back for comparison. The mice were sacrificed at 1 and 2 weeks after injection and histological evaluations were performed. Irradiatedβ-glucan demonstrated a significantly larger volume than nonirradiatedβ-glucan in the back of nude mice with less inflammatory reaction. After unilateral recurrent laryngeal nerve section in New Zealand White rabbits, irradiated and nonirradiatedβ-glucan were injected into paralyzed vocal folds. Irradiatedβ-glucan remained at the paralyzed vocal fold without definite inflammatory signs on endoscopy. High-speed recordings of vocal fold vibration showed decreased vocal gap in irradiated group compared to nonirradiated group. Histologically, the laryngeal epithelium and lamina propria remained intact, without inflammatory cell infiltration. Our newly developed injection material, irradiatedβ-glucan, showed excellent biocompatibility and remained longer than nonirradiatedβ-glucanin vivo, suggesting irradiated hydrogels as a new therapeutic approach that may be useful for the long-term treatment of vocal fold palsy.

Author(s):  
Zhipeng Lou ◽  
Junshi Wang ◽  
James J. Daniero ◽  
Haibo Dong ◽  
Jinxiang Xi

Abstract In this paper, a numerical approach combined with experiments is employed to characterize the airflow through the vocal cord. Rabbits are used to perform in vivo magnetic resonance imaging (MRI) experiments and the MRI scan data are directly imposed for the three-dimensional (3D) reconstruction of a 3D high-fidelity model. The vibration modes are observed via the in vivo high-speed videoendoscopy (HSVM) technique, and the time-dependent glottal height is evaluated dynamically for the validation of the 3D reconstruction model. 72 sets of rabbit in vivo high-speed recordings are evaluated to achieve the most common vibration mode. The reconstruction is mainly based on MRI data and the HSVM records are supporting and validate the 3D model. A sharp-interface immersed-boundary-method (IBM)-based compressible flow solver is employed to compute the airflow. The primary purpose of the computational effort is to characterize the influence of the vocal folds that applied to the airflow and the airflow-induced phonation. The vocal fold kinematics and the vibration modes are quantified and the vortex structures are analyzed under the influence of vocal folds. The results have shown significant effects of the vocal fold height on the vortex structure, vorticity and velocity. The reconstructed 3D model from this work helps to bring insight into further understanding of the rabbit phonation mechanism. The results provide potential improvement for diagnosis of human vocal fold dysfunction and phonation disorder.


2021 ◽  
Vol 11 (16) ◽  
pp. 7256
Author(s):  
Daryush D. Mehta ◽  
James B. Kobler ◽  
Steven M. Zeitels ◽  
Matías Zañartu ◽  
Emiro J. Ibarra ◽  
...  

The purpose of this paper is to report on the first in vivo application of a recently developed transoral, dual-sensor pressure probe that directly measures intraglottal, subglottal, and vocal fold collision pressures during phonation. Synchronous measurement of intraglottal and subglottal pressures was accomplished using two miniature pressure sensors mounted on the end of the probe and inserted transorally in a 78-year-old male who had previously undergone surgical removal of his right vocal fold for treatment of laryngeal cancer. The endoscopist used one hand to position the custom probe against the surgically medialized scar band that replaced the right vocal fold and used the other hand to position a transoral endoscope to record laryngeal high-speed videoendoscopy of the vibrating left vocal fold contacting the pressure probe. Visualization of the larynx during sustained phonation allowed the endoscopist to place the dual-sensor pressure probe such that the proximal sensor was positioned intraglottally and the distal sensor subglottally. The proximal pressure sensor was verified to be in the strike zone of vocal fold collision during phonation when the intraglottal pressure signal exhibited three characteristics: an impulsive peak at the start of the closed phase, a rounded peak during the open phase, and a minimum value around zero immediately preceding the impulsive peak of the subsequent phonatory cycle. Numerical voice production modeling was applied to validate model-based predictions of vocal fold collision pressure using kinematic vocal fold measures. The results successfully demonstrated feasibility of in vivo measurement of vocal fold collision pressure in an individual with a hemilaryngectomy, motivating ongoing data collection that is designed to aid in the development of vocal dose measures that incorporate vocal fold impact collision and stresses.


2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Luchao Li ◽  
Shuo Zhao ◽  
Zhengfang Liu ◽  
Nianzhao Zhang ◽  
Shuo Pang ◽  
...  

AbstractReceptor tyrosine kinase (RTK) inhibitors, such as sunitinib and sorafenib, remain the first-line drugs for the treatment of mRCC. Acquired drug resistance and metastasis are the main causes of treatment failure. However, in the case of metastasis Renal Cell Cancer (mRCC), which showed a good response to sunitinib, we found that long-term treatment with sunitinib could promote lysosome biosynthesis and exocytosis, thereby triggering the metastasis of RCC. By constructing sunitinib-resistant cell lines in vivo, we confirmed that TFE3 plays a key role in the acquired resistance to sunitinib in RCC. Under the stimulation of sunitinib, TFE3 continued to enter the nucleus, promoting the expression of endoplasmic reticulum (ER) protein E-Syt1. E-Syt1 and the lysosomal membrane protein Syt7 form a heterodimer, which induces ER fragmentation, Ca2+ release, and lysosomal exocytosis. Lysosomal exocytosis has two functions: pumping sunitinib out from the cytoplasm, which promotes resistance to sunitinib in RCC, releasing cathepsin B (CTSB) into the extracellular matrix (ECM), which can degrade the ECM to enhance the invasion and metastasis ability of RCC. Our study found that although sunitinib is an effective drug for the treatment of mRCC, once RCC has acquired resistance to sunitinib, sunitinib treatment will promote metastasis.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryosuke Nakamura ◽  
Nao Hiwatashi ◽  
Renjie Bing ◽  
Carina P. Doyle ◽  
Ryan C. Branski

AbstractVocal fold (VF) fibrosis is a major cause of intractable voice-related disability and reduced quality of life. Excision of fibrotic regions is suboptimal and associated with scar recurrence and/or further iatrogenic damage. Non-surgical interventions are limited, putatively related to limited insight regarding biochemical events underlying fibrosis, and downstream, the lack of therapeutic targets. YAP/TAZ integrates diverse cell signaling events and interacts with signaling pathways related to fibrosis, including the TGF-β/SMAD pathway. We investigated the expression of YAP/TAZ following vocal fold injury in vivo as well as the effects of TGF-β1 on YAP/TAZ activity in human vocal fold fibroblasts, fibroblast-myofibroblast transition, and TGF-β/SMAD signaling. Iatrogenic injury increased nuclear localization of YAP and TAZ in fibrotic rat vocal folds. In vitro, TGF-β1 activated YAP and TAZ in human VF fibroblasts, and inhibition of YAP/TAZ reversed TGF-β1-stimulated fibroplastic gene upregulation. Additionally, TGF-β1 induced localization of YAP and TAZ in close proximity to SMAD2/3, and nuclear accumulation of SMAD2/3 was inhibited by a YAP/TAZ inhibitor. Collectively, YAP and TAZ were synergistically activated with the TGF-β/SMAD pathway, and likely essential for the fibroplastic phenotypic shift in VF fibroblasts. Based on these data, YAP/TAZ may evolve as an attractive therapeutic target for VF fibrosis.


2017 ◽  
Vol 09 (05) ◽  
pp. 1750064 ◽  
Author(s):  
A. Van Hirtum ◽  
X. Pelorson

Experiments on mechanical deformable vocal folds replicas are important in physical studies of human voice production to understand the underlying fluid–structure interaction. At current date, most experiments are performed for constant initial conditions with respect to structural as well as geometrical features. Varying those conditions requires manual intervention, which might affect reproducibility and hence the quality of experimental results. In this work, a setup is described which allows setting elastic and geometrical initial conditions in an automated way for a deformable vocal fold replica. High-speed imaging is integrated in the setup in order to decorrelate elastic and geometrical features. This way, reproducible, accurate and systematic measurements can be performed for prescribed initial conditions of glottal area, mean upstream pressure and vocal fold elasticity. Moreover, quantification of geometrical features during auto-oscillation is shown to contribute to the experimental characterization and understanding.


2011 ◽  
Vol 63 (3) ◽  
pp. 134-141 ◽  
Author(s):  
Andrea Nacci ◽  
Bruno Fattori ◽  
Giovanni Segnini ◽  
Iacopo Dallan ◽  
Erica Panicucci ◽  
...  

2017 ◽  
Vol 8 (6) ◽  
pp. 173-182 ◽  
Author(s):  
Andrea Fanelli ◽  
Daniela Ghisi ◽  
Pierangelo Lora Aprile ◽  
Francesco Lapi

Observational studies and meta-analyses have shown that the administration of nonsteroidal anti-inflammatory drugs (NSAIDs), especially when prescribed at high doses for long periods of time, can potentially increase the risk of cardiovascular diseases. The increased thrombotic risk related to the use of NSAIDs is mainly due to their cyclooxygenase 2 selectivity. The dosage use, the formulation selected and the duration of the therapy are other factors that can significantly impact on the cardiovascular risk. In order to minimize the risk, prescription of the right drug based on the patient’s features and the different safety profiles of several NSAIDs that are available on the market is key for their appropriate administration. Despite the baseline cardiovascular and gastrointestinal risk of each patient, monitoring of patients is suggested for increases in blood pressure, development of edema, deterioration of renal function, or gastrointestinal bleeding during long-term treatment with NSAIDs.


2006 ◽  
Vol 134 (1-2) ◽  
pp. 11-21 ◽  
Author(s):  
Milos Jovanovic

Introduction. Some factors significant for development of mechanical injuries of the eyeball have been analyzed in the study. Objective. Basic objective of such analysis was prevention and reduction of these injuries. Method. Mechanical injuries of the eyeball in patients hospitalized at the Institute of Eye Disease, CCS in Belgrade, in five year period have been analyzed. Only patients with severe eye injuries were hospitalized. The following parameters were analyzed: sex, age, occupation of patients, residence, time of the inflicted injury, i.e. by months in a year, days in a week and hours in a day, place and way of inflicting the injury as well as visual acuity on admission. In addition, the type of injury was analyzed, i.e. contusion or penetrating with all resulting complications. Finally, the timing of primary surgical management of the eye injury was specified, if required. Results. A total number of hospitalized patients with mechanical eye injuries was 1642 during the last five years, meaning that one injury occurred daily. There were 1381 males and 261 females, meaning that males were 5.3 times more the victims of mechanical eye injuries. Out of all the injured, 861 (52.4%) were from rural environment, while 781 (47.6%) were urban population. The proportion of injuries of the right or the left eye was nearly equal, while both eyes were simultaneously injured in 21 (1.3%) cases. The injuries were inflicted in all ages, but most frequently in working population ranging from 16 to 55 years, accounting for 60.8%. Unfortunately, a lot of the injured were children up to 15 years of age - 19.4%. The most commonly injured were workers - 39.8%, followed by students - 17.5%. A piece of wood was the cause of injury in 21.8%, sharp and pointed objects in 17.2%, hammer and metal in 14.2%, glass in 11.6%, and other different causes in varying percentage. There were also rare causes of injuries, such as those caused by zip, dog bite, rooster?s bill, etc. According to months in a year and days in a week, the injuries were almost evenly distributed. Considering the period of a day, even 77.4% of the injuries occurred during daytime, from 10 a.m. to 10 p.m. The highest percentage - 43.5% - of the injuries occurred while working something out of working place, while 24.5% of injuries were inflicted at working places. On admission, the majority of patients - 32.9% had visual acuity L+P+, but this visual acuity ranged from amaurosis to 1.0. There were 746 (45.4%) contusion injuries and 870 (53.0%) penetrating injuries. The rest were the injuries of other ocular adnexa. The majority of primary wound managements were performed in the first 24 hours of the injury - 67.1%. Conclusion. It may be concluded that working population and students are most commonly injured, and that men are five times more frequently injured than women; then, a piece of wood, sharp objects and glass are the most often causes of injury; the number of contusion and penetrating injuries is equal, and that required primary surgical wound management is most often performed in the first 24 hours from the injury. Further analysis of these factors suggests that many of these injuries could have been prevented, and consequently long-term treatment and treatment costs could have been evaded. Most important is that permanent disability due to visual impairment or even blindness of the injured eye could have been avoided.


Author(s):  
Andreas M. Kist ◽  
Pablo Gómez ◽  
Denis Dubrovskiy ◽  
Patrick Schlegel ◽  
Melda Kunduk ◽  
...  

Purpose High-speed videoendoscopy (HSV) is an emerging, but barely used, endoscopy technique in the clinic to assess and diagnose voice disorders because of the lack of dedicated software to analyze the data. HSV allows to quantify the vocal fold oscillations by segmenting the glottal area. This challenging task has been tackled by various studies; however, the proposed approaches are mostly limited and not suitable for daily clinical routine. Method We developed a user-friendly software in C# that allows the editing, motion correction, segmentation, and quantitative analysis of HSV data. We further provide pretrained deep neural networks for fully automatic glottis segmentation. Results We freely provide our software Glottis Analysis Tools (GAT). Using GAT, we provide a general threshold-based region growing platform that enables the user to analyze data from various sources, such as in vivo recordings, ex vivo recordings, and high-speed footage of artificial vocal folds. Additionally, especially for in vivo recordings, we provide three robust neural networks at various speed and quality settings to allow a fully automatic glottis segmentation needed for application by untrained personnel. GAT further evaluates video and audio data in parallel and is able to extract various features from the video data, among others the glottal area waveform, that is, the changing glottal area over time. In total, GAT provides 79 unique quantitative analysis parameters for video- and audio-based signals. Many of these parameters have already been shown to reflect voice disorders, highlighting the clinical importance and usefulness of the GAT software. Conclusion GAT is a unique tool to process HSV and audio data to determine quantitative, clinically relevant parameters for research, diagnosis, and treatment of laryngeal disorders. Supplemental Material https://doi.org/10.23641/asha.14575533


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