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Objective: To investigate the changes in otoacoustic emissions (OAEs) for detecting the ototoxicity of cisplatin and to study the possible preventive effect of N-acetylcysteine (NAC) in cisplatin ototoxicity.

Introduction: Ototoxicity is a health problem appearing after powerful treatments in serious health conditions. It is sometimes inevitable when treatment of the serious disease is required. Cisplatin is an antineoplastic agent which was investigated previously to reveal increased nitrogen and reactive oxygen radicals that damages hair cells, resulting in ototoxicity. N-acetylcysteine, previously shown to decrease ototoxicity caused by different agents, is known to be a powerful in vitro antioxidant. Probably N-acetylcysteine, in addition to its antioxidant effect, blocks a cascade where reactive oxygen species result in apoptosis in the cochlea. Objectives: The possible preventive effect of N-acetylcysteine in cisplatin ototoxicity was studied with auditory brain stem responses, otoacoustic emissions, and histopathological investigation of the cochlea in a scanning electron microscopy. Methods: This study was conducted on 21 Wistar Albino rats in four groups. 1 mL/kg/day three times in total intraperitoneal (i.p.) Saline (n = 5), 500 mg/kg/day i.p. three times in total N-acetylcysteine (n = 5), i.p. 15 mg/kg cisplatin alone (single dose) (n = 5) and i.p. 15 mg/kg cisplatin plus 500 mg/kg/day N-acetylcysteine (n = 6) were administered. The rats were anesthetized to study the hearing tests before and after the experiment. The rats were sacrificed to investigate the cochleas by scanning electron microscopy. Results: Auditory brain stem responses and otoacoustic emissions values were attenuated in the cisplatin group. The group that received N-acetylcysteine in addition to cisplatin had better auditory brain stem responses thresholds and otoacoustic emissions. The samples obtained from the cisplatin group showed surface irregularities, degeneration areas, and total or partial severe stereocilia losses. The changes were milder in the cisplatin + N-acetylcysteine group. Conclusion: Cisplatin ototoxicity can be detected by auditory brain stem responses and otoacoustic emissions testing in rats. N-acetylcysteine may protect the cochlear cells from histopathological changes. We concluded that N-acetylcysteine given 4 h after cisplatin injection has a potential otoprotective effect against cisplatin ototoxicity. which suggests it could be used in clinical trials. Resumo: Introdução: A ototoxicidade é um problema que pode ocorrer após certos tipos de tratamentos para condições graves de saúde. Às vezes é inevitável quando o tratamento da doença é necessário. A cisplatina é um agente antineoplásico cujo uso em pesquisas anteriores demonstrou aumentar os radicais livres de nitrogênio e espécies reativas de oxigênio que danificam as células ciliadas e resultam em ototoxicidade. Por outro lado, a N-acetilcisteína, que já demonstrou diminuir a ototoxicidade causada por diferentes agentes, é conhecida por ser um potente antioxidante in vitro. Provavelmente a N-acetilcisteína, além de seu efeito antioxidante, bloqueia uma cascata onde espécies reativas de oxigênio resultam em apoptose na cóclea. Objetivos: Estudar o possível efeito preventivo da N-acetilcisteína na ototoxicidade por cisplatina por meio de potencial evocado auditivo de tronco encefálico, emissões otoacústicas e investigação histopatológica da cóclea por microscopia eletrônica de varredura. Método: Este estudo foi realizado em 21 ratos albinos Wistar, separados em quatro grupos. Foram administrados: 1 mL/kg/dia intraperitoneal (i.p.) de solução salina (n = 5), três vezes no total; 500 mg/kg/dia i.p. de N-acetilcisteína (n = 5), três vezes no total; 15 mg/kg i.p. (dose única) somente de cisplatina (n = 5) e 15 mg/kg i.p. de cisplatina e 500 mg/kg/dia i.p. de N-acetilcisteína (n = 6). Os ratos foram anestesiados para estudo dos testes auditivos antes e depois do experimento. Os ratos foram sacrificados para investigação da cóclea por microscopia eletrônica de varredura. Resultados: Os potenciais evocados auditivos de tronco encefálico e os valores das emissões otoacústicas estavam atenuados no grupo cisplatina. O grupo que recebeu N-acetilcisteína além da cisplatina apresentou melhores limiares de respostas auditivas do tronco encefálico e emissões otoacústicas. As amostras obtidas do grupo cisplatina apresentaram irregularidades de superfície, áreas de degeneração, com perdas graves totais ou parciais de estereocílios. As alterações foram mais leves no grupo cisplatina + N-acetilcisteína. Conclusão: A ototoxicidade por cisplatina pode ser detectada por meio de potenciais evocados auditivos de tronco encefálico e pelo teste de emissões otoacústicas em ratos. A N-acetilcisteína pode proteger as células cocleares contra alterações histopatológicas. Concluímos que a N-acetilcisteína administrada 4 horas após a injeção de cisplatina tem potencial efeito otoprotetor contra a ototoxicidade por cisplatina e pode ser utilizada em ensaios clínicos. Keywords: Cisplatin, Electron microscopy, Hearing tests, N-acetylcysteine, Ototoxicity, Palavras-chave: Cisplatina, Microscópio eletrônico, Testes de audição, N-acetylcysteine, Ototoxicidade

WOS: 000386676300007 The incidences of extracranial and intracranial complications of acute otitis media (AOM) in children have markedly decreased in the postantibiotic era. Zygomatic abscesses are the rarest type of abscesses originating from mastoiditis. This paper presents a case with a zygomatic abscess as a complication of acute coalescent mastoiditis in a 7-year-old girl who underwent cortical mastoidectomy and myringotomy-ventilation tube insertion.

Aim Hearing loss is the most common sensory disorder that affects approximately one per 1000 live births. With this project, we aimed to identify gene variants that were common causes of hearing loss in Turkey to contribute to the planning of genetic screening programs for hearing loss, as well as to improve genetic counseling to affected families. Material and methods Twenty-one families with at least two affected individuals and parental consanguinity who presented with non-syndromic severe-to-profound sensorineural hearing loss were included in this study. We first screened for mutations in GJB2 and mitochondrial DNA 12S RNA genes. Subsequently, we genotyped the TMIE c.250C>T and SNP markers flanking the SLC26A4, MYO7A, MYO15A, OTOF, CDH23, TMIE, TECTA, PCDH15, TMC1, TMPRSS3, TMHS genes in the remaining twelve families without mutations in GJB2. Results Screening for mutations in GJB2 gene showed c.[35delG];[35delG] mutation in four families, c.[35delG];[507C>A] mutation in two families, c.[35delG];[-23+1G>A] mutation in one family, and c.457G>A heterozygous mutation in one family. Genotyping SNP markers showed the c.[250C>T];[250C>T] mutation in TMIE in one family. A homozygous region with SNP genotypes was detected with the OTOF gene in one family, the TMPRSS3 gene in another family, and also a homozygous region was detected with TMHS, OTOF, and TMPRSS3 genes in another family. Conclusions Further research will be required to determine the genetic bases of hearing loss in families with non-syndromic hearing loss.

Objective The possible preventive effect of N-acetylcysteine (NAC) in gentamicin ototoxicity was studied with auditory brain stem responses (ABRs), otoacoustic emissions (OAEs), and histopathological investigation of the cochlea. Materials and methods This study is conducted on 36 rats in three groups. Gentamicin, gentamicin plus NAC, and NAC alone were intraperitoneally administered for 15 days. The rats were sacrificed to study the cochleas after testing hearing levels. Results ABR thresholds and OAEs were attenuated in the gentamicin group, in which apoptosis was detected with histopathological investigation. The group that received NAC in addition to gentamicin had better ABR thresholds and better OAEs. The histopathological evidence of apoptosis in was considerably less in this group. Conclusion Gentamicin ototoxicity can be detected by ABR and OAE testing in rats, and NAC may protect the cochlear cells from apoptosis.

OZET Sessiz otitis medya, ilerleyici otojenik bir hastaliktir. Bu subkli- nik enfeksiyoz hastalik timpanik zar normal olmasina ragmen mastoid kemik hucrelerini ve mukozalarini etkiler. Antibiyotik sonrasi donemde klasik mastoidit sikliginda ciddi bir dusus mevcut olmakla birlikte, otitis medya icin yetersiz veya etkisiz antibiyotik kullanimina bagli gelisen sessiz mastoidit halen ha- yati tehdit eden bir antitedir. Bu yazida, sessiz mastoidite bagli gelisen epidural ve subdural ampiyem olgusu sunulmaktadir. Hastaya mastoidektomi uygulanmistir. Mastoidektomi sonrasi olgu hastaliksiz takiptedir. Bu yazinin amaci, kolaylikla gozden kacirilabilecek olan sessiz otitis medyaya okuyucunun dikka- tini cekmektir. Anah tar kelimeler: Mastoidit, otitis medya, subdural ampiyem

Background Otomycosis is defined as an infection of the external ear canal with fungal agents. The treatment of the disease is cleansing and drying of the external ear canal, identification and treatment of any predisposing factors and application of topical antifungal agents. Terbinafine is used as an antifungal agent to treat otomycosis. We proposed to investigate the probable ototoxic effect of terbinafine solution on auditory brain stem response (ABR) and distortion product otoacoustic emission (DPOAE) when applied intratympanically in the middle ear of rats. Methods The experiment was performed on 30 female Wistar albino rats. Thirty animals were divided into three groups of 10 animals each. 1% terbinafine solution was administered to the first group (group T). The second group (group G) was administered 40 mg/ml gentamicin solution (ototoxic control). The third group (group S) was administered saline solution (negative control). Baseline DPOAE measurements and ABR testing from the left ears were obtained from the animals in all groups under general anesthesia. Ear solutions were applied in the middle ear intratympanically with a dental needle. Treatment was initiated after baseline measurements and repeated once every two days for fifteen days. Results Pre and post-treatment DPOAE responses for all tested frequencies of group T and Group S showed no statistically significant difference. However, the group G demonstrated a significant change in ABR thresholds and DPOAE responses. Conclusions Terbinafine solution is a broad spectrum antifungal agent effective in the treatment of otomycosis. The present study demonstrated that its direct administration in the middle ear of rats does not affect inner ear function as measured by ABR and DPOAE responses.

Aim. Peritonitis is currently one of the leading complications of continuous ambulatory peritoneal dialysis (CAPD) treatment. Aminoglycosides and vancomycin are used in the treatment of CAPD peritonitis despite their potential risk for ototoxicity. N-acetylcysteine (NAC) is a molecule used in the treatment and prophylaxis of many diseases related to oxidative stress. The aim of this study was to examine whether ototoxicity due to antibiotics used in the treatment of CAPD peritonitis can be prevented by NAC. Methods. Sixty patients, who first developed CAPD peritonitis attacks from February 2008 to April 2010 were included in this study. Patients were divided into two groups, those taking an additional NAC treatment (n ¼ 30) and a control group (n ¼ 30). Low- and high-frequency hearing function tests were performed on the two groups before treatment (baseline), at the end of the first (early follow-up) and the fourth week after the treatment (late follow-up). Total doses of vancomycin and amikacin were recorded. Results. There was no statistically significant difference between the groups in terms of hearing functions at the beginning. However, patients taking NAC had better hearing function test results 4 weeks after the treatment compared with those of the control group (P < 0.05). There were no statistical differences between posttreatment low-frequency hearing function tests conducted at the baseline and the first and the fourth weeks in patients taking NAC. The first and the fourth week’s low-frequency hearing functions worsened when compared with the baseline low-frequency results in the control group (P < 0.001). It was found that NAC had a protective effect against ototoxicity on low-frequency (0.25–8 KHz) hearing functions. The first and the fourth week’s high-frequency hearing functions improved when compared with baseline high-frequency hearing functions in patients taking NAC (P < 0.05), while they worsened. The first and fourth week’s high-frequency tests worsened when compared with the baseline high-frequency tests in the control group (P < 0.001). Conclusions. The present study suggests that intraperitoneal aminoglycoside and vancomycin administration in CAPD patients may cause low- and high-frequency hearing loss, and this ototoxic effect is related to the dose given. It was found that when the antioxidant NAC is administered alone, it prevents ototoxicity, associated with intraperitoneal amikacin and vancomycin in patients with CAPD peritonitis. In addition, it was revealed that NAC may also have a curative effect on impaired high-frequency hearing functions.

Aim. Aminoglycosides have been used in the treatment of CAPD peritonitis despite their potential risk for ototoxicity. The ototoxicity risk of intraperitoneally administered aminoglycosides has been investigated by a number of studies. However, their results are somewhat conflicting. The aim of the present study was to examine the frequency of hearing loss and the correlation between the repeated doses of aminoglycosides and hearing loss in CAPD peritonitis therapy. Methods. Hearing functions of the CAPD patients who had developed peritonitis and had been treated with various antibiotics including aminoglycosides were compared with those CAPD patients who had never developed peritonitis. Threshold values for hearing were determined through "pure tone audiometry" measurements. Results. Hearing threshold levels of the patients with history of peritonitis were found to be significantly higher in both lower [pure tone averages - 1 (PTA-1)] and higher [pure tone averages - 2 (PTA-2)] frequencies, when compared to the ones with no history of peritonitis (p values were 0.001 and 0.007, respectively). Conclusion. The present study showed that intraperitoneal aminoglycoside administration in CAPD patients is associated with the development of hearing loss. The severity of hearing loss may range from mild hearing loss to profound deafness. A remarkable correlation exists between the severity of the hearing loss and the repeated and total aminoglycoside dose received.