ABSTRACT
INTRODUCTION: The pathogenesis of alopecia areata (AA) remains incompletely understood. Different cytokines may play a role in AA. Tumor necrosis factor-alpha (TNF-α) has been shown to be inhibitory to hair follicle growth in in vitro studies suggesting that it may play an important role in AA. This study was conducted to assess the presence of TNF-α in lesional and nonlesional skin of AA, to review its possible role in AA, and to show whether AA is a systemic or localized disease by comparing the level of TNF-α between lesional and nonlesional skin biopsies of the patients. MATERIALS AND METHODS: Thirty patients with AA and thirty age- and sex-matched healthy controls were included in the study. A 4 mm punch skin biopsy was taken from lesional and nonlesional skin of every patient, as well as from the normal skin of each individual in the control group for immunohistochemical analysis of TNF-α. RESULTS: The level of TNF-α in lesional skin biopsies was significantly higher than in nonlesional skin biopsies of patients as well as controls' biopsies. Furthermore, TNF-α level in nonlesional biopsies of patients was significantly higher than the level in controls' biopsies. CONCLUSIONS: We concluded that skin of AA has a high level of TNF-α (a normal inhibitor of hair follicle growth in vitro). This high level may point to the important role of TNF-α in AA. Further studies should be conducted to detect the level of TNF-α in long-standing AA and the more severe cases of AA.
ABSTRACT
OBJECTIVE: To investigate the effect of bridging defects in chronic spinal cord injury using peripheral nerve grafts combined with a chitosan-laminin scaffold and enhancing regeneration through them by co-transplantation with bone-marrow-derived mesenchymal stem cells. METHODS: In 14 patients with chronic paraplegia caused by spinal cord injury, cord defects were grafted and stem cells injected into the whole construct and contained using a chitosan-laminin paste. Patients were evaluated using the International Standards for Classification of Spinal Cord Injuries. RESULTS: Chitosan disintegration leading to post-operative seroma formation was a complication. Motor level improved four levels in 2 cases and two levels in 12 cases. Sensory-level improved six levels in two cases, five levels in five cases, four levels in three cases, and three levels in four cases. A four-level neurological improvement was recorded in 2 cases and a two-level neurological improvement occurred in 12 cases. The American Spinal Impairment Association (ASIA) impairment scale improved from A to C in 12 cases and from A to B in 2 cases. Although motor power improvement was recorded in the abdominal muscles (2 grades), hip flexors (3 grades), hip adductors (3 grades), knee extensors (2-3 grades), ankle dorsiflexors (1-2 grades), long toe extensors (1-2 grades), and plantar flexors (0-2 grades), this improvement was too low to enable them to stand erect and hold their knees extended while walking unaided. CONCLUSION: Mesenchymal stem cell-derived neural stem cell-like cell transplantation enhances recovery in chronic spinal cord injuries with defects bridged by sural nerve grafts combined with a chitosan-laminin scaffold.
