N Mosaffa , F Labibi ,
Volume 57, Issue 1 (7 1999)
Abstract
Natural Killer (NK) cells are the main lymphocyte population expressing P75 B chain of the IL-2 receptor (IL-2R). Consequently, incubation of peripheral blood lymphocytes with IL-2 induce selective activation of NK cells and results in NK activity and generation of Lymphokine activated killer (LAK) cells activity and proliferation. One of the early events during IL-2 activation of peripheral blood lymphocyte in both rodents and humans is adherence of some NK cells to plastic surface. The cells adherence to plastic after 24 hr of culture with IL-2 are almost exclusively CD56+, have the morphology large granular cells to yield a highly entiched population of activated NK cells that have been used for systemic adoptive immunotherapy. To test these hypothesis, we used highly purified population of human peripheral NK cells through the biological and nonimmunclogical phenotyping technique. Blood mononuclear cells were separated by centrifugation of ficol-hypaque gradient from normal blood donor (20-30 years age). We depleted after purification of nonadherent cells with nylonwool. We collected with rosette technique to remove cells with high affinity SRBC receptors. These cells separate in two parts A-NK and NA-NK by mononuclear celss activated supernatant media. The main objective results of this study show that the subpopulation of human NK cell which develope early adherent to plastic surface in the presence of supernatant mononuclear celss activation media was functionally more cytotoxic and killed K562 targets in single cell sytotoxicity manner and LDH activity assay than nonadherent NK cells and resting NK cells
Mirvakili S.a, Baradaranfar M.h, Karimi Gh, Labibi M,
Volume 65, Issue 2 (8 2008)
Abstract
Background: Traumatic tympanic membrane (TM) perforation is a common injury of the ear with a high rate of spontaneous healing if the patients strictly adhere to water precautions. The purpose of this study was to determine the factors involved in the spontaneous healing of traumatic TM perforations in order to ascertain the best treatment plan including observation, paper patch and finally surgery.
Methods: In this correlative–descriptive study, we recorded the outcome of each patient with three-month follow up. Included in this study were a total of 202 forensic medicine patients from the Dept. of Otolaryngology Head & Neck Surgery at the Yazd University of Medical Sciences, Yazd, Iran. All patients included in this study had traumatic TM perforation. Based on otoscopic examination, the perforations were classified as pinpoint or large. All patients received an audiometry exam and were followed for three months. The data was collected using a special form and analyzed by chi-square test, Fisher exact test and ANOVA.
Results: This study consisted of 118 male and 84 female patients with a mean age of 23.6 years (6-48 years). The types of trauma included compression injury (104 patients), instrumental injury (59 patients), burn–slag injury (2 patients) and blast injury (1 patient). One hundred and eighty patients had pinpoint TM perforations, 99.4% of which healed spontaneously by the second month, and 32 patients had large TM perforations, 50% of which healed spontaneously by the second month. During the first month, 87.3% of the patients observing water precautions had healed, however the healing rate was only 5.6% in patients not adhering to water precautions, who suffered from otorrhea. Therefore, during this study, 185 (91.58%) patients had spontaneous healing by two months and only 6 patients of remaining 17 patients healed with paper patch. The mean hearing loss at 500, 1000 and 2000 Hz was 10.55 dB (5-30 dB).
Conclusion: In our experience, patients with traumatic TM perforations have higher spontaneous healing rate when observing water precautions. Furthermore, we recommend observation and paper patching for three months before attempting any surgical intervention in such patients.