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G Adamopoulos

Publications and source records attributed to G Adamopoulos.

47 records · Page 3Linked to original sources

Effect of the number of averaged responses in transient evoked otoacoustic emissions on the results of neonatal hearing screening.

This study examined the effect of the number of accepted responses in transient evoked otoacoustic emissions on the results of neonatal hearing screening programmes. The ILO88 Otodynamics Analyzer Quickscreen programme was used for all testing, and a three-stage procedure was adopted by averaging 20, 30, and 260 low-noise samples in total. The results were recorded after each stage of the testing in those cases in which, after the first 20 accepted responses, the "pass" criteria were met. Under these circumstances, 117 ears were included in the study from a total number of 334 screened ears. It was concluded that 20 averaged quiet responses are adequate for screened newborn babies to pass the test if the conditions of the "pass" criteria are fulfilled at this stage. In the rest of the newborn babies, testing should be continued using a larger number of clicks. For diagnostic and clinical purposes, the full 260 quiet samples must be used since the results indicated statistically better scores in response and reproducibility measures after the 260 averaged responses.

Cochlea↗

Topoisomerase II alpha expression in squamous cell carcinomas of the head and neck.

The aim of the present study was to examine topoisomerase II alpha (topo II alpha) expression in cancers of the head and neck and to establish a correlation with clinicopathological parameters and survival. Paraffin embedded tissue specimens (studied by immunohistochemistry), from 103 consecutive patients with squamous cell carcinoma of the head and neck regions, were examined on the primary tumor (96 patients) and on recurrence (7 patients). Immunostaining evaluation was quantified by examining at least 1,000 neoplastic cells and counting the percentage of positively stained nuclei. Topoisomerase II alpha expression was correlated with age, gender, stage, site of the disease, tumor differentiation, response to chemotherapy, disease-free survival and overall survival. More than half of the specimens had a high expression of topoisomerase II alpha (> or = 15% positive neoplastic cells). Topoisomerase II alpha expression was significantly higher in tumors of low and moderate differentiation versus tumors of high differentiation (P = 0.00001). There was also a significant difference in topo II alpha in specimens of responders to chemotherapy versus non-responders (P = 0.02), although the cytotoxic drugs used do not belong to topoisomerase II alpha antagonists. The correlation of high topoisomerase II alpha expression and stage of disease, age, gender, primary site, recurrence, disease-free survival and overall survival was not statistically significant. In conclusion, topoisomerase II alpha is highly expressed in histological specimens of the majority of patients with head and neck cancers; mainly, it is related to a significant degree to low and moderately differentiated tumors versus highly differentiated ones. High expression of topoisomerase II alpha is also significantly related to response to chemotherapy.

Adult↗

p53, p21 and p27 protein expression in head and neck cancer and their prognostic value.

Histological specimens from 62 laryngeal and 31 oral carcinomas were immunohistochemically assessed for p53, p21 and p27 proteins; cases with > 10% labelled nuclei were considered as positive. p21 showed higher expression in patients > 65-years-old (P = 0.04), in chemotherapy responders (P = 0.02), and in stage III patients with longer overall survival (P = 0.02), representing the only independent prognostic factor in the multivariate analysis. In addition, stage III patients with p53-/p21+ showed the longest survival whereas those with p53+/p21- tumors showed the shortest overall survival (P = 0.02). A significant influence on the survival of stage III patients was also found for the combinations of p21 and p27 proteins with p21+/p27- imparting the best and p21-/p27+ the worst prognosis (P = 0.04). p27 expression was significantly related to oral cancer specimens (P = 0.04) and to moderate and high tumor grade (P = 0.01). p53 expression was not significantly related to any of the examined clinicopathological characteristics. Our findings indicated that, by functionally promoting apoptosis, p21 seems to play a key role in the successful response to chemotherapy and may be considered as a predictive factor of a better prognosis in stage III patients with head and neck cancers.

Adult↗