A case report of a malignant peripheral nerve sheath tumor of the oral cavity in neurofibromatosis type 1.

Patients with neurofibromatosis type 1 develop both benign and malignant tumors at an increased frequency. Most of the malignant peripheral nerve sheath tumors (MPNSTs) are considered as high-grade sarcomas originating from tissues of mesenchymal origin. It is generally accepted that MPNSTs occur in about 2% to 5% of neurofibromatosis patients. In this paper, we present a 16-year-old male patient with neurofibromatosis who developed MPNST of the retromolar area. The mass enlarged rapidly in a period of 6 weeks. The patient was treated surgically, and a tumor mass with a diameter of 7 × 6 × 4 cm was excised, but after 8 months a recurrence was observed at the same site. The sarcomatous change in a neurofibroma has an extremely poor prognosis, so patients with neurofibromatosis should be closely monitored for a possible malignancy. A rapid change in size of a preexisting neurofibroma, infiltration of the adjacent structures, intralesional hemorrhage, and pain indicate a possible malignant transformation to MPNST.

Protective role of resveratrol against cisplatin induced ototoxicity in guinea pigs.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of systemic administration of resveratrol against cisplatin-induced ototoxicity in guinea pigs. MATERIALS AND METHODS: Healthy guinea pigs (n=24) were randomly divided into four groups. Group 1 (n=6) received resveratrol+cisplatin, group 2 (n=6) received 4% ethanol+cisplatin, group 3 (n=6) received cisplatin, and group 4 (n=6) received saline. Cisplatin was administered at a dose of 10mg/kg/day on days 14 and 15 of the study. Resveratrol (10mg/kg/day), 4% ethanol, and saline were administered throughout the study. Baseline auditory brainstem responses (ABR) (4 kHz, 8 kHz, and click stimulus) were determined for all groups. ABR was repeated 72 h after the last dose of cisplatin in order to record the threshold shifts. The ABR threshold shifts for the click stimulus, 4-kHz- and 8-kHz-frequency stimuli were compared after drug administration. After follow-up ABRs the animals sacrificed under deep sedation and their cochleae were removed. Left cochleae were immediately harvested for measurement of level of reactive oxygen species (ROS). Right cochleae were prepared for histological changes which were observed by scanning electron microscopy (SEM). RESULTS: For the all stimulus, there was a significant threshold difference among the groups (p<0.01). Group 3 had a significantly higher threshold shift at all stimuli when compared with groups 1 and 4. There was no significant threshold shifts in all stimuli between groups 2 and 3. The resveratrol-treated group 1 showed preservation of threshold in ABR (p ≤ 0.05). SEM showed that inner and outer hair cells were preserved in the group 1. Level of reactive oxygen species (ROS) were significantly higher in groups 2 and 3 compared with groups 1 and 4 (p ≤ 0.05). CONCLUSION: These results indicated that systemic administration of resveratrol afforded statistically significant protection to the cochlea of guinea pigs from cisplatin toxicity. Experimental dose of resveratrol injections may have a protective effect against cisplatin ototoxicity in guinea pigs.

Effect of topical use of mitomycin C and 5-fluorouracil on the closure time of myringotomies created by radiofrequency unit.

CONCLUSION: Both mitomycin C (MC) and 5-fluorouracil (5-FU) had a significant effect in prolonging the patency rate of radiofrequency myringotomy. OBJECTIVE: To compare the effect of topical use of MC and 5-FU on the closure time of myringotomies created by a radiofrequency unit. MATERIALS AND METHODS: Myringotomies were performed using a radiofrequency unit on 80 tympanic membranes of 40 rats. Rats were divided into two study groups and one control group. MC (0.4 mg/ml) and 5-FU (50 mg/ml) pledgets were applied topically in the right ears (study groups, 20 ears each) for 10 min and saline pledgets in the left ears (control group, 40 ears). Animals were monitored using otomicroscopy weekly and patency rates were recorded until myringotomy closure. RESULTS: The mean patency times were 4.85 weeks for the MC group and 3.90 weeks for the 5-FU group. The mean patency rate for the control side was 1.30 weeks. The log-rank test revealed both study groups to have a significantly longer patency time than the control group (p<0.0001). Although the patency rate was found to be higher in the MC-treated group than the 5-FU-treated group, this difference was not statistically significant (p>0.05).

Ototoxic effect of topical ciclopirox as an antimycotic preparation.

OBJECTIVE: To evaluate the ototoxicity of ciclopirox-containing solution as an otologic preparation for the treatment of otomycosis. BACKGROUND: Ciclopirox is a synthetic antimycotic agent available in a variety of formulations to treat superficial fungal infections. Ciclopirox has demonstrated both fungicidal and fungistatic activity in vitro against a broad spectrum of pathogenic fungi. It also possesses a broad-spectrum antibacterial properties, anti-inflammatory, and antiedema effect. The ototoxic effect of ciclopirox-containing solutions has not been known, so the current study was designed to observe the ototoxic effect of this solution experimentally. MATERIALS AND METHODS: Experiments were performed in 22 young male albino guinea pigs (weight, 450-550 g). The 10 animals in the experimental group received ciclopirox solution, and the control group was divided into two groups of six animals each. The first group received saline solution (negative control) and the second received gentamicin (40 mg/mL; ototoxic control). Under general anesthesia, pretreatment auditory brainstem responses (ABRs) from the right ears were obtained from the animals in all groups. The right tympanic membranes were totally perforated, and a small piece of Gelfoam was applied to the middle ear directly to the round window membrane. Ear solutions were applied through transcanal approach to the middle ear twice a day in 2 weeks. Twenty-two animals of perforated tympanic membrane were observed during a 2-week period. Posttreatment ABRs were obtained in all groups in a week after the last administration. RESULTS: Baseline ABR results were normal in right ears of all animals tested. Animals undergoing placement of Gelfoam with either ciclopirox solution or saline in the middle ear showed no changes in the ABR threshold. The gentamicin group showed a significant change in the ABR threshold. CONCLUSION: In the guinea pig, when applied topically to the middle ear, ciclopirox does not cause a reduction in the ABR threshold. Because its safety has not yet been confirmed in patients, caution should be observed when prescribing this agent.

Ototoxic effect of Burow solution applied to the guinea pig middle ear.

OBJECTIVE: To analyze the ototoxicity of Burow solution as an otologic preparation. BACKGROUND: Burow solution has been used for years in the treatment of acute or chronic otitis externa and chronic suppurative otitis media. This acidic solution has antibacterial and antiedematous properties. Ototoxic effect of Burow solution has not been known, so the current study was designed to observe the ototoxic effect of Burow solution experimentally. MATERIALS AND METHODS: Experiments were performed in 32 young, male albino guinea pigs (weight, 450-550 g). Twenty animals in the experimental group were divided into 2 groups of 10 animals each. The first group received 13% Burow solution (13% aluminum subacetate), and the second received 4% Burow solution (4% aluminum subacetate). Twelve animals in the control group were divided into 2 groups of 6 animals each. The first group received gentamicin (40 mg/mL; ototoxic control), and the second received saline solution (negative control). Under general anesthesia, pretreatment auditory brainstem responses (ABRs) from the right ear were obtained from the animals in all groups. The right tympanic membranes were widely perforated, and a small piece of Gelfoam was applied to the middle ear. Ear solutions at concentrations of 0.1 mL were applied through transcanal approach to the middle ear twice a day in 10 days. Under general anesthesia, the Gelfoam was removed from the right middle ear, and posttreatment ABRs were obtained 14 days later after the initial time in all groups. RESULTS: Baseline ABR results were normal in right ears of all animals tested. Animals undergoing placement of Gelfoam with either 13% Burow solution, 4% Burow solution, or saline in the middle ear showed no changes in ABR threshold. The gentamicin group showed significant change in the ABR threshold. CONCLUSION: Burow solution was considered to be an effective and safe otologic preparation.

The effects of topical agents of fluticasone propionate, oxymetazoline, and 3% and 0.9% sodium chloride solutions on mucociliary clearance in the therapy of acute bacterial rhinosinusitis in vivo.

OBJECTIVES: The aims of the study were to determine: 1) how mucociliary activity in acute bacterial rhinosinusitis is affected; 2) how this activity is changed by therapy; 3) the effects of topical agents on mucociliary clearance, and 4) the most appropriate topical agent(s) to be used in the therapy of sinusitis. STUDY DESIGN: Five groups of patients with acute bacterial rhinosinusitis were studied prospectively. METHODS: All patients had 500 mg oral amoxicillin and 125 mg oral clavulanic acid preparations given three times daily for 3 weeks. According to the topical agent applications, these groups included: group I (n = 12), no topical treatment was given; group II (n = 14), two puffs for each nostril once daily of 50 microg/100 mL fluticasone propionate was given; group III (n = 9), one puff for each nostril three times daily of 0.05% oxymetazoline was given; group IV (n =12), 3% sodium chloride (NaCl) (buffered to pH 6.5-7 at room temperature) was given; and group V (n =13), 10-mL solutions of 0.9% NaCl (buffered to pH 6.5--7 at room temperature) were given for nasal irrigations three times daily. All patients had medication for 3 weeks and were controlled each week. The saccharin method was used to measure nasal mucociliary clearance. To investigate the early effects of the topical agents for groups II to V, an additional test was repeated 20 minutes after the basal mucociliary clearance recordings. The test was repeated in the first, second, and third weeks of the treatment. RESULTS: The mucociliary clearance was significantly slower in the acute bacterial rhinosinusitis group than in the control group. There was no significant difference between the basal mucociliary clearance and the 20th minute mucociliary clearance of the fluticasone propionate and 0.9% NaCl solution groups. The mean values of the basal and the 20 minute's mucociliary clearance of the oxymetazoline group were 24.72 +/- 6.16 and 15.5 +/- 7.45 minutes, respectively, which were statistically significant. The mean values of the basal and the 20th minute mucociliary clearance of the 3% NaCl solution groups were 19.45 +/- 9.35 and 15.45 +/- 8.20 minutes, respectively, which were also statistically significant. In the first group (without topical treatment), the basal mucociliary clearance became significantly shorter after the second week of treatment. In the first and second weeks of the treatment of the oxymetazoline group, the mucociliary clearance did not change significantly, but after the third week the mucociliary clearance was significantly shorter. In the 3% NaCl solution group, significant improvement began from the first week and continued through the third week. Comparing the basal and the third weeks' mucociliary clearance values among the groups, the oxymetazoline and 3% NaCl solution groups revealed more significant improvement than the other groups, but this improvement was not different from the improvement of group I. There was still a statistically significant difference in the mucociliary clearance of the post-treatment sinusitis groups from the control group. CONCLUSIONS: The oxymetazoline and 3% NaCl solution groups seemed to be more effective in mucociliary clearance, but there was no significant difference in improvement among the groups. The improvement of acute bacterial rhinosinusitis takes more than 3 weeks, according to the mucociliary clearance values of the groups.