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Dive into the research topics where Gideon Bahar is active.

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Featured researches published by Gideon Bahar.


Cancer | 2007

Salivary analysis in oral cancer patients: DNA and protein oxidation, reactive nitrogen species, and antioxidant profile.

Gideon Bahar; Raphael Feinmesser; Thomas Shpitzer; Aaron Popovtzer; Rafael M. Nagler

Free radicals such as reactive oxygen species (ROS) and reactive nitrogen species (RNS), which induce oxidative and nitrative stress, are main contributors to oral carcinogenesis. The RNS (nitrosamines: nitrates, NO3, and nitrites, NO2) are also produced by the reaction of ROS and other free radicals with nitric oxide (NO) and are therefore in equilibrium with it.


Clinical Cancer Research | 2006

Concomitant Analysis of Salivary Tumor Markers—A New Diagnostic Tool for Oral Cancer

Rafael M. Nagler; Gideon Bahar; Thomas Shpitzer; Raphael Feinmesser

Purpose: Oral squamous cell carcinoma (OSCC) is a common human malignancy. Circulatory epithelial tumor markers were previously investigated in the serum of OSCC patients but almost never in their saliva, in spite of the fact that there is a direct contact between the saliva and the oral cancer lesion. The purpose of the current study was to examine tumor markers in the saliva of OSCC patients. Experimental Design: We measured the concentrations of the six most studied epithelial serum circulatory tumor markers in the saliva of OSCC (tongue) patients. Results: Significant increases (of 400%) in salivary concentrations of Cyfra 21-1, tissue polypeptide antigen, and CA125 were shown. Salivary concentrations of CA19-9, SCC, and carcinoembryonic antigen were increased without statistical significance. A concurrent analysis of the three significantly increased markers revealed sensitivity, specificity, and negative and positive predictive values of 71%, 75%, 71%, and 75%, respectively. Conclusions: The increase reported in salivary tumor markers may be used as a diagnostic tool, especially when a concurrent analysis for significantly increased markers is done. Salivary testing is noninvasive, making it an attractive, effective alternative to serum testing, and the possibility of developing home testing kits would further facilitate it as a diagnostic aid, enabling patients to monitor their own health at home and is important for those who live far from their treatment centers and especially for those at risk of developing OSCC.


Laryngoscope | 2004

Squamous cell carcinoma of the oral tongue in young patients.

Aron Popovtzer; Thomas Shpitzer; Gideon Bahar; Gideon Marshak; David Ulanovski; Raphael Feinmesser

Objectives/Hypothesis: Cancer of the tongue is reported with increasing frequency in young people. The objective of this work was to study the biologic and clinical course of the disease in this group. The clinical course of the disease in this patient group remains controversial.


Otolaryngology-Head and Neck Surgery | 2006

Adenoidectomy: Long-term Follow-Up

Ben-Zion Joshua; Gideon Bahar; Jaqueline Sulkes; Thomas Shpitzer; Eyal Raveh

OBJECTIVE: To assess the long-term (3-5 years) success of adenoidectomy and reasons for unsatisfactory results. STUDY DESIGN AND SETTING: The parents of all children who underwent adenoidectomy alone at a major tertiary center from 1998 to 2000 were asked to complete a questionnaire assessing their childs well-being and symptomatology 3-5 years after surgery; some were invited for follow-up. Symptom improvement, persistent symptoms, and adenoid regrowth were evaluated. RESULTS: Among the 206 parents who complied, 74%-87% reported improvement in all main symptoms: nasal obstruction, snoring, chronic rhinorrhea, hyponasal speech, and obstructive sleep disorder. At follow-up (n = 36), the symptomatic patients had significantly more anatomic nasal abnormalities (P = 0.01) and a higher rate of significant adenoid enlargement (P = 0.08), 3 patients (19%) vs none (0%). CONCLUSIONS AND SIGNIFICANCE: Adenoidectomy alone is satisfactory treatment for nasal obstruction and obstructive sleep apnea in selected children. Though some adenoid regrowth is not rare, clinically significant adenoid regrowth is infrequent. Persistent or recurrent symptoms are attributable mainly to nasal pathology.


American Journal of Otolaryngology | 2003

Basaloid squamous carcinoma of the larynx

Gideon Bahar; Raphael Feinmesser; Aharon Popovtzer; David Ulanovsky; Ben I. Nageris; Gideon Marshak; Meora Feinmesser

BACKGROUND Basaloid squamous cell carcinoma (BSCC) is a distinct variant of squamous cell carcinoma that was first described by Wain et al in 1986. Since then, about 160 cases have been reported in the literature. Only 40 cases have been described in the larynx. METHODS Four cases of BSCC of the larynx treated in our department between 1986 and 2000 are presented. The clinical features, biological behavior, and histopathological and immunohistochemical characteristics of this uncommon tumor are described, and the relevant literature is reviewed. RESULTS The main clinical presentation did not differ from other histological types of laryngeal carcinoma. The clinical course, however, was much more aggressive. All the patients received aggressive therapy including radical surgery and radiation. Two patients received chemotherapy. Two of the 4 patients presented died of distant metastasis shortly after diagnosis and treatment. CONCLUSIONS The finding of this study with a limited number of patients supports previous reports suggesting that BSCC is a highly aggressive tumor that presents in older population with male predominance. The frequency of associated regional as well as distant metastases suggests that aggressive treatment is indicated and that systemic chemotherapy should be contemplated.


American Journal of Otolaryngology | 2003

The cytological and clinical value of the thyroid follicular lesion

Gideon Bahar; Diana Braslavsky; Thomas Shpitzer; Raphael Feinmesser; Sali Avidan; Aharon Popovtzer; Segal Karl

BACKGROUND The main limitation of fine-needle aspiration (FNA) is its limited distinction between neoplastic and benign lesions. We summarize our experience with thyroid nodules that were defined as follicular lesions by comparing the clinical and cytological features of the thyroid follicular lesions that were examined histologically to define the most reliable criteria of malignancy. METHODS The medical records of all patients who underwent thyroid aspiration at Rabin Medical Center from 1999 to 2000 were reviewed for a diagnosis of follicular lesion that warranted surgery (N = 58). The cytology and pathology reports of the patients who met these criteria were reviewed and compared with the original reports. RESULTS The incidence of malignancy in follicular lesions of the thyroid is about 26%. There was a significant correlation between a histologic diagnosis of carcinoma and the cytologic findings of nuclear grooves (P =.041), solid arrangement (P =.019), hypercellularity (P =.01), and hypercellularity to colloid amount ratio (P =.016). Nodular size was predictive of malignancy. No correlation was found between patient age or gender and tendency toward malignancy. CONCLUSIONS The combination of cytological characteristics and the size of the nodule aspirate are predictive values of malignancy. We believe that every follicular lesion should be excised to obtain a definitive histological diagnosis based on capsular or vascular invasion.


Otolaryngology-Head and Neck Surgery | 2006

Thyroid Cancer in Children: Management and Outcome Experience of a Referral Center

Aron Popovtzer; Thomas Shpitzer; Gideon Bahar; Raphael Feinmesser; Segal K

OBJECTIVE: To shed light on the discrepancy between the advanced stage at presentation and high recurrence rate of well-differentiated thyroid cancer in children and the overall good survival. DESIGN AND METHODS: The files of 75 children with well-differentiated thyroid cancer treated from 1954 to 2001 in a major tertiary-care hospital were reviewed for disease course, management, and outcome. RESULTS: Sixty patients (80%) had positive neck metastases with involvement of central compartment lymph nodes in all, lateral neck nodes in 36, and distant metastases in 4. Sixty-seven patients underwent total thyroidectomy with adjuvant radioiodine treatment and 8 underwent hemithyroidectomy; all had concomitant neck treatment. The rate of local (5%) and neck (9%) recurrence was similar to the total rate reported in adults. Total thyroidectomy led to a significantly lower recurrence rate (7.5%) than hemithyroidectomy (38%; P < 0.005). Type of neck dissection did not affect recurrence or appearance of distant metastases. All deaths (n = 2) were due to distant metastases, whereas 30% of adult deaths are due to local or neck disease. CONCLUSIONS: The treatment of choice for well-differentiated thyroid cancer in young patients is total thyroidectomy. Neither regional disease at presentation nor recurrences affect survival.


Otolaryngology-Head and Neck Surgery | 2006

Acute parotitis as a complication of fine-needle aspiration in Warthin’s tumor. A unique finding of a 3-year experience with parotid tumor aspiration

Gideon Bahar; Mickey Dudkiewicz; Raphael Feinmesser; Ben-Zion Joshua; Diana Braslavsky; Aharon Popovtzer; Dora Galil; Thomas Shpitzer

OBJECTIVE/HYPOTHESIS: Fine needle aspiration (FNA) is an accurate, cost-effective tool for the study of salivary gland lesions. Although complications are extremely rare, salivary gland FNA can lead to hemorrhage, facial nerve injury, and cellulitis at the needle puncture site. Some studies suggest that FNA can cause infarction or metaplastic transformation of benign Warthins tumors. We review our recent experience with FNA of the parotid gland, focusing on possible complications and pitfalls. STUDY DESIGN AND SETTING: The medical records of all patients who underwent FNA of the parotid gland from 2000 to 2002 in the Department of Otolaryngology-Head and Neck Surgery of a major tertiary-care referral center were reviewed. Cytological results were compared to the histological diagnosis and complications were recorded. RESULTS: Of the 256 lesions aspirated, 99 patients (39%), were cytologically diagnosed as benign tumors, including 31 (12%) Warthins tumors, of which 16/17 resected and confirmed histologically. Five patients with Warthins tumor had post-FNA parotitis and were treated accordingly. CONCLUSIONS: The combination of cystic spaces surrounded by oncocytic cells and a poor blood supply makes the tumor susceptible to infarction and inflammation. Our findings indicate that FNA is a strong and reliable tool in the investigation of the salivary glands. Nevertheless, when Warthins tumor is clinically suspected on the basis of its location (tail of the parotid gland), cystic texture, patient sex (male) and age, one should consider parotitis as a possible complication.


Antioxidants & Redox Signaling | 2013

Is Human Saliva an Indicator of the Adverse Health Effects of Using Mobile Phones

Yaniv Hamzany; Raphael Feinmesser; Thomas Shpitzer; Aviram Mizrachi; Ohad Hilly; Roy Hod; Gideon Bahar; Irina Otradnov; Moshe Gavish; Rafael M. Nagler

Increasing use of mobile phones creates growing concerns regarding harmful effects of radiofrequency nonionizing electromagnetic radiation on human tissues located close to the ear, where phones are commonly held for long periods of time. We studied 20 subjects in the mobile-phone group who had a mean duration of mobile phone use of 12.5 years (range 8-15) and a mean time use of 29.6 h per month (range 8-100). Deaf individuals served as controls. We compared salivary outcomes (secretion, oxidative damage indices, flow rate, and composition) between mobile phone users and nonusers. We report a significant increase in all salivary oxidative stress indices studied in mobile phone users. Salivary flow, total protein, albumin, and amylase activity were decreased in mobile phone users. These observations lead to the hypothesis that the use of mobile phones may cause oxidative stress and modify salivary function.


Otolaryngology-Head and Neck Surgery | 2005

Facial palsy associated with acute otitis media

Aron Popovtzer; Eyal Raveh; Gideon Bahar; Yael Oestreicher-Kedem; Rafael Feinmesser; Ben I. Nageris

OBJECTIVE: Facial palsy secondary to acute otitis media is rarely encountered today. The aim of the present study was to review the characteristics of the disease and propose the proper management. STUDY DESIGN: File review. SETTING: University-affiliated tertiary referral center. MAIN OUTCOME MEASURES: Disease course, management and outcome were recorded. RESULTS: Sixty-five children with facial palsy were identified, of whom 13 (20%) had acute otitis media. The otitis media preceded the facial palsy in all cases by 1 to 21 days (average 5 days). House-Brackmann grade ranged from 2 to 5 (average 3.5). The recovery period was varied and unpredictable, ranging in duration from 1 to 180 days (average 68 days). Treatment was conservative, except for insertion of a ventilation tube in 2 cases. CONCLUSIONS: Considering that all the patients recovered, conservative treatment, including myringotomy and intravenous antibiotics, may be the correct approach to facial palsy associated with acute otitis media.

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Rafael M. Nagler

Technion – Israel Institute of Technology

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