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Abstract Polypeptide GFs are a diverse group of hormone-like agents that regulate growth and differentiation through cell surface receptors. They are generally represented by homologous families containing several members with distinct overlapping receptor interactions and hence, responsive tissue specificities. Similarly, their receptors are also clustered in family groups of sequence-related proteins. from a functional point of view, polypeptide GFs can conveniently be divided into four categories: 1. Tissue GFs 2. Hemopoietic GFs 3. Neurotrophic factors 4. Cytokines There is considerable overlap in the activities of many of these factors and many can be listed in more than one category. Like most proteins, polypeptide GFs can also be subdivided into ”families”. This is well illustrated by the IGFs, the FGFs and more recently, the NGFs. The primary role of peptide GFs contributes to the fundamental intercellular signaling within tissues that underlies a complex interaction of cell proliferation, hypertrophy, migration, differentiation and senescence which proceeds within strict temporal and anatomical constraints. FGFs that signal through FGFRs regulate a wide range of biological functions, including cell proliferation, survival, migration and differentiation. Among the signal pathways, RAS/MAP kinase is known to be predominant in the case of FGFs. Organs transplantation or implantation of synthetic devices is the currently available and most used methods to treat loss of tissues and organs in humans. However, there is a continue demanding of new solutions and approaches for tissues failure since the definitive solution is far to be achieved. For this reason, regenerative medicine and tissue engineering are becoming of great interest as the alternative strategy to repair or regenerate damaged tissue. Regenerative medicine provides alternatives to organ transplantation, which is limited in applicability owing to immune responses against allografts and the large disparity between the need for organs and tissues and the number available for transplantation. GFs are critical signaling molecules that instruct cells during development, and one may achieve tissue regeneration in the adult by enabling control over GF delivery. The ideal materials are biodegradable, biocompatible and able to serve as a supporting artificial ECM until the natural tissue is produced by the neighboring cells as the biomaterials gradually degrade. The use of GFs has become greatly attractive to achieve the above mentioned goals, because their activity affect and regulate many cellular processes involved during tissue healing. The VF is a multilayered vibrator structure which gives the VFs their mechanical properties. These structures oscillate during the production of sound. The SLP is normally very loose and contains abundant interstitial proteins such as HA, fibronectin and proteoglycans such as fibromodulin, decorin and versican. In a VF lesion, such as a VF scar, VF sulcus and atrophy, the SLP has deposits of disorganized thick collagen bundles with little HA. These histological changes induce VF scarring, vibratory suppression and glottal insufficiency. These changes induce severe symptoms such as breathy dysphonia, phonasthenia and aspiration associated with communication disorders and fatal pneumonia. Various surgical attempts have been performed for these cases; however, a particular treatment has not been established, because the wound-healing process for regeneration is unpredictable. Also UVFP induces not only severe dysphonia but aspiration as well, which leads to reduction in the patient’s quality of life. Various treatments have been used, including laryngeal framework surgery and injection laryngoplasty. However, for patients with mild symptoms of UVFP and individuals with poorer general health, it is best to receive minimally invasive therapy. Even in severe cases, a six months observation period is required from onset to laryngeal framework surgery because some UVFP patients experience spontaneous recovery during their clinical course. Patients under observation should also receive some type of therapy to mitigate the severity of dysphonia and aspiration during the observation period. Although various surgical strategies have been applied in these cases, a definitive treatment has not been established because these surgical procedures are sometimes performed under general anesthesia and dysphonia often remain unresolved. Recent progress in regenerative medicine has made it possible to develop tissue engineering techniques by using cells, scaffolds, and GFs. GFs affect cell function, extrinsic application of GFs may induce the regenerative process. One promising GF is bFGF which is a member of the FGF family and a promising agent for regenerative medicine of the larynx. Regenerative treatments using bFGF injection of the SLP of the VFs effectively improved dysphonia in VF lesions and in UVFP. Cases of severe dysphonia caused by VF lesions and paralysis were treated by the single bFGF injection method show significant improvements occurred in MPT, MFR, PR, jitter, SSF and VHI. The single injection method is easy to perform as an office procedure. The bFGF is suitable for office procedures because it is less toxic and readily available as an injectable aqueous solution. Furthermore, bFGF is a type of regenerative medicine that maintains VF-specific structure, which differs from various foreign material injections. To summarize the reviewed literature the issue of using bFGF injection to treat VF lesions and VF paralysis is still controversial and the stage is open for more studies. Surgical procedures are performed directly on the VFs with the aim of: 1- Closing a phonatory gap causedb by paralytic, sulcus, scar and atrophy. 2- Improving the vibratory movement and restoration of the normal mucosal wave. 3- Correction of VFs position and/or tension. The objective is to create a common language in order to improve the surgical description of the procedures proposed by different authors for addressing specific VF lesions or disorders. This common language will simplify postoperative outcome comparisons, standardize phonosurgical procedures and facilitate the teaching of phonosurgery. |