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

Abstract

This study explored a novel strategy to restore the vocal gap by using cross-linked β-glucan hydrogel by γ-irradiation. An aqueous solution of 5 wt% β-glucan was prepared and cross-linked using 60Co γ irradiation. Ten nude mice were injected with 0.8 mL of irradiated β-glucan on the left back and the same volume of nonirradiated β-glucan on the right back for comparison. The mice were sacrificed at 1 and 2 weeks after injection and histological evaluations were performed. Irradiated β-glucan demonstrated a significantly larger volume than nonirradiated β-glucan in the back of nude mice with less inflammatory reaction. After unilateral recurrent laryngeal nerve section in New Zealand White rabbits, irradiated and nonirradiated β-glucan were injected into paralyzed vocal folds. Irradiated β-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, irradiated β-glucan, showed excellent biocompatibility and remained longer than nonirradiated β-glucan in vivo, suggesting irradiated hydrogels as a new therapeutic approach that may be useful for the long-term treatment of vocal fold palsy.

Ultrasonic Method to Synthesize Glucan-g-poly(acrylic acid)/Sodium Lignosulfonate Hydrogels and Studies of Their Adsorption of Cu2+ from Aqueous Solution

“…Sodium lignosulfonate as a byproduct in the pulping and papermaking process contains lots of functional groups, and they are inexpensive, renewable, and readily available relative to other materials. Therefore, a value-added utilization method of sodium lignosulfonate can be beneficial to not only the biorefinery process, but also to the pulping industry. , Glucan, a group of polysaccharides, is present in the cell walls and well-tolerated by humans and animals . It has the effect of scavenging free-radicals, antiradiation, dissolving cholesterol and preventing hyperlipidemia and is widely used in medicine, food, cosmetics and other industries …”

“…24,25 Glucan, a group of polysaccharides, is present in the cell walls and well-tolerated by humans and animals. 26 It has the effect of scavenging free-radicals, antiradiation, dissolving cholesterol and preventing hyperlipidemia and is widely used in medicine, food, cosmetics and other industries. 27 The study is aimed to synthesize GL-g-PAA, SLS-g-PAA, and GL-g-PAA/SLS hydrogels via ultrasonic solution polymerization and use them as adsorbents to remove the Cu 2+ ion from aqueous solutions.…”

Regeneration of Paralyzed Vocal Fold by the Injection of Plasmid DNA Complex-Loaded Hydrogel Bulking Agent

“…To investigate the functionality of the VF, macroscopic vibrations of the VF were induced by excised laryngeal setup at 24 week (Figure S2). After total laryngectomy, tissue-trimming and mounting in the phonation induction device were performed in accordance with a previously described method . VF vibrations were recorded with a high-speed video camera (MotionXtra NR4S2, DEL Imaging Systems, USA) at a speed of 8000 frames per second with a 300 W xenon light source (PS-NP1; Polarion, Republic of Korea).…”

“…After total laryngectomy, tissue-trimming and mounting in the phonation induction device were performed in accordance with a previously described method. 7 VF vibrations were recorded with a high-speed video camera (MotionXtra NR4S2, DEL Imaging Systems, USA) at a speed of 8000 frames per second with a 300 W xenon light source (PS-NP1; Polarion, Republic of Korea). Ten serial images from one cycle of VF vibration were taken.…”

“…Damaged laryngeal nerves cause not only atrophy of the VF muscles but also histologic changes of the lamina propria. − These histopathological changes of the VF eventually lead to a severe deterioration of the vocalization. Various artificial materials have already been applied to improve VF contact and structural regeneration. − Among them, injectable materials have received more attention than three-dimensional (3D) scaffolds because they can be delivered into vocal muscle in a noninvasive manner . Also, 3D scaffolds tend to become dislodged by VF movement.…”