INTRODUÇÃO: A exposição a níveis elevados de pressão sonora é a segunda causa mais comum de perda auditiva sensorioneural adquirida. Está relacionada à morte celular por apoptose, necrose e/ou necrose programada (necroptose) devido ao dano mecânico e/ou metabólico, ocasionando a degeneração de estruturas cocleares como células ciliadas, sobretudo externas, células de suporte e de fibras aferentes do nervo coclear. Estudos têm demostrado um aumento na citocina inflamatória TNFa após a exposição ao ruído, bem como a melhoria auditiva relacionada ao uso de etanercepte, que é um bloqueador destacitocina. Neste contexto, este estudo teve por objetivo avaliar o efeito do silenciamento gênico do Tnfa na audição de ratos Wistar, expostos ao ruído branco, e identificar o perfil de expressão gênica na via metabólica desse gene. METODOLOGIA: Foram incluídos ratos Wistar do sexo masculino, jovens com limiar auditivo no Peate clique de 50 dBSPL. Os animais foram submetidos à introdução do siRNA Tnfa em uma orelha, e siRNA scramble na orelha contralateral por via trans-timpânica com posterior exposição à 120 dBSPL de ruído branco por 3h. Foi realizado Peate clique e remoção das cócleas para obtenção do cDNA e avaliação da expressão gênica da via metabólica do Tnfa por meio de qRT-PCR. Um grupo de animais, não submetidos ao silenciamento, foi exposto ao ruído para análise dessa via metabólica. Para o cálculo da expressão gênica relativa (Rq) utilizamos o método do deltaCT comparativo e o teste t-Student pareado para avaliar os parâmetros no Peate clique. RESULTADOS: A taxa de silenciamento observada foi de 74,1%. A média do limiar eletrofisiológico nas orelhas silenciadas foi estaticamente melhor que a orelha scramble (p < 0,001) com valores médios de 49,5 +- 10.5. A amplitude média da onda I em 80 dBSPL e das ondas II e IV em 90 dBSPL foi estatisticamente maior na orelha siRNA Tnfa, sem alteração na latência nas intensidades audíveis,para ambos os lados. A exposição ao ruído promoveu aumento da expressão do gene Tnfa e de seu receptor Tnfrsf1A, 24h após à exposição, associado ao aumento da expressão de genes relacionados à apoptose e diminuição de genes relacionados à sobrevida celular. CONCLUSÃO: O ruído promoveu aumento de expressão do gene Tnfa e de genes envolvidos na apoptose, associado à perda auditiva em modelo experimental. A administração trans-timpânica do siRNA Tnfa promoveu preservação do limiar eletrofisiológico e da amplitude da onda I, II e IV no Peate clique, após exposição ao ruído intenso, sugerindo que a inibição deste pode ser uma estratégia de preservação auditiva promissora. O silenciamento do Tnfa inibiu a disfunção coclear após estímulo acústico, sugerindo que esta proteína é um dos principais agentes envolvidos na perda auditiva induzida pelo ruído, devendo ser considerada como alvo terapêutico na estratégia de preservação auditiva / INTRODUCTION: Exposure to high levels of sound pressure is the second most common cause of acquired sensorineural hearing loss. It is related to cell death through apoptosis, necrosis and/or programmed necrosis (necroptosis) due to mechanical and/or metabolic damage, causing the degeneration of cochlear structures, such as cilliary cells, mainly external, as well as support cells and afferent fibers of the cochlear nerve. Studies have demonstrated an increase in the inflammatory cytokine TNFalfa after exposure to noise, as well as auditory improvement related to the use of etanercept, a cytokine blocker. In this context, this study aimed to evaluate the effect of Tnfa gene silencing on the hearing of Wistar rats exposed to white noise and to identify the expression profile in the metabolic pathway of this gene. METHODOLOGY: Young male Wistar rats with 50 dBSPL threshold in auditory brainstem responses click (ABR) were included in this study and submitted to the introduction of the TnfasiRNA in one ear and the scramble siRNA in the contralateral ear by trans-tympanic route, with subsequent exposure to 120 dB SPL of white noise for 3h. ABR was measured and the cochleae were dissected and used for the extraction of total RNA to obtain cDNA and conduct evaluations of the Tnfa metabolic pathway gene expression by qRT-PCR. A group of animals, not submitted to silencing, was exposed to noise to analyze this metabolic pathway. The relative gene expression (Rq) was calculated by the comparative deltaCT method and the paired Student t-test were applied to evaluate the parameters of the ABR click. RESULTS: The silencing rate was 74.1%. The mean electrophysiological threshold in the silenced ears was statistically higher than the scrambled ear (p < 0.001) with mean values of 49.5 +- 10.5. The mean amplitudes of wave I at 80 dBSPL and waves II and IV at 90dBSPL were statistically higher in the TnfasiRNA ear, with no change in latency at audible intensities for both sides. Noise exposure promoted increased expression of the Tnfa gene and its receptor, Tnfrsf1A, 24h after exposure, associated with increased expression of genes related to apoptosis and decreased expression of genes related to cell survival. CONCLUSIONS: Noise exposure promoted increased in Tnfa gene expression as well as in genes involved in apoptosis, associated with hearing loss in an experimental model. The trans-tympanic administration of TnfasiRNA promotes the preservation of the electrophysiological threshold and the amplitude of wave I, II and IV in the ABR click, after exposure to intense noise, suggesting that this inhibition may be a promising auditory preservation strategy. The Tnfa knockdown inhibited cochlear dysfunction after acoustic injury, suggesting that this protein plays an important role in noise induced hearing loss and should be considered a therapeutic target in auditory preservation strategies

Made available in DSpace on 2016-04-27T18:12:17Z (GMT). No. of bitstreams: 1 Gabriela Lopes.pdf: 708382 bytes, checksum: f9c6f44eb1450e2f8fb7419125767777 (MD5) Previous issue date: 2007-02-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: Every society depends directly or indirectly on the road transport efficiency, which is mainly executed by truck drivers. On duty of this function, these professionals can show several health problems such as hearing impairment. Objective: This assignment has studied the hearing and the self-perception of the hearing handicap in truck drivers. Method: It was evaluated 75 truck drivers, male gender and ages between 27 to 61 years old, with professional experience between five to 40 years. It was accomplished: anamnesis, audiometric evaluation and also was applied a questionnaire, the Hearing Handicap Inventory for Adults (HHIA). Noise Induced Hearing Loss (NIHL) was classified according to the Group criterion used by Fiorini (1994). Audiometric evaluation also was classified according to Parrado-Moran, Fiorini (2003), taking into consideration the results for both ears separately. Results: 50 out of 75 (66.7%) have shown results within normal standards (Group 1), 20 out of 75 (26.7%) have been classified as suggestive of noise induced hearing loss (NIHL) (Group 2) and 5 out of 75 like the others (6.6%). Out of 50 Group 1 audiograms (71.4%), 31 were normal with bilateral notch (62.0%) and out of 20 Group 2 audiograms (28.6%), 16 (80.0%) were suggestive of bilateral NIHL. The greatest compromise was found in the frequency range of 4 kHz, 6 kHz and 8 kHz. Qualitative variables: years of duty profession (p=0.049) and age (p=0.049) have statistically influenced the audiometric evaluation results. Out of 50 truck drivers (71.4%) who presented normal hearing thresholds (Group 1), 43 subjects (86.0%) did not have a perceived hearing handicap, 6 (12.0%) had a mild/moderate perception and 1(2.0%) a severe/significant hearing handicap perception. Out of 20 truck drivers (28.6%) who presented suggestive NIHL (Group 2), 16 subjects (80.0%) did not show any degree of hearing handicap, 3 (15.0%) have presented it mild/moderate and one (5.0%) severe/significant. The largest compromise was found in the frequencies of 4 kHz, 6 kHz and 8 kHz. In relation to self-perception of the hearing handicap, 7 drivers (14%) from Group 1 and 4 (20.0%) from Group 2 have shown self-perception of the hearing handicap. However, 43 drivers (86.0%) of Group 1 and 16 (80.0%) of Group 2 did not show any perception. With this, it was noticed that not even all the drivers with suggestive NIHL showed a hearing handicap self-perception and those within normal hearing standards have presented it. Conclusion: The prevalence of hearing disorders on the analyzed population was 28.6%. Besides the years of duty profession and the age determined statistically the results of this audiometric evaluation and it did not have any connection with the results of the self-perceived hearing handicap / Introdução: Toda sociedade depende direta ou indiretamente da eficiência do transporte rodoviário, que é executado principalmente pelos motoristas de caminhão. No desempenho de sua função, estes profissionais podem apresentar diversos problemas de saúde e dentre eles, a deficiência auditiva. Objetivo: Este trabalho visou estudar a audição e a auto-percepção do handicap auditivo de motoristas de caminhão. Método: Foram avaliados 75 motoristas de caminhão, do sexo masculino, com idades entre 27 a 61 anos e com tempo de profissão entre cinco e 40 anos. Os sujeitos responderam a uma anamnese, realizaram avaliação audiométrica e preencheram um questionário de auto-percepção do handicap auditivo - Hearing Handicap Inventory for Adults (HHIA). A Perda Auditiva Induzida por Ruído (PAIR) foi classificada segundo o critério de Grupos utilizado por Fiorini (1994). A avaliação audiométrica também foi classificada de acordo com Parrado-Moran, Fiorini (2003), considerando os resultados de ambas as orelhas separadamente. Resultados: Do total, 50 (66,7%) apresentaram resultados dentro dos padrões de normalidade (Grupo 1) e 20 (26,7%) foram classificados como sugestivos de PAIR (Grupo 2) e cinco como Outros (6,6%). Dentre os 50 audiogramas do Grupo 1 (71,4%), 31 foram dentro dos padrões de normalidade, com entalhe bilateral (62,0%) e dos 20 audiogramas do Grupo 2 (28,6%), 16 (80,0%) foram sugestivos de PAIR bilateral. O maior comprometimento foi encontrado na faixa de freqüências de 4 kHz, 6 kHz e 8 kHz. As variáveis qualitativas: anos de profissão (p=0,049) e idade (p=0,007) influenciaram estatisticamente os resultados da avaliação audiométrica. Do total de 50 motoristas de caminhão (71,4%) que apresentaram audição dentro dos padrões de normalidade (Grupo 1), 43 sujeitos (86,0%) não apresentaram auto-percepção do handicap auditivo, seis (12,0%) apresentaram auto-percepção leve/moderada do handicap auditivo e um (2,0%) demonstrou auto-percepção severa/significativa do handicap auditivo. Dos 20 motoristas (28,6%) que apresentaram perdas auditivas sugestivas de PAIR (Grupo 2), 16 sujeitos (80,0%) não apresentaram auto-percepção do handicap auditivo, três (15,0%) apresentaram auto-percepção leve/moderada do handicap auditivo e um (5,0%) demonstrou auto-percepção severa/significativa do handicap auditivo. Com isso, foi observado que nem todos os sujeitos com alterações auditivas sugestivas de PAIR demonstraram auto-percepção do handicap auditivo, porém, aqueles com audição dentro dos padrões de normalidade puderam apresentá-la. Conclusões: A prevalência de alterações auditivas na população estudada foi de 28,6%. Além disso, não houve associação entre os resultados da avaliação audiométrica e a auto-percepção do handicap auditivo

Made available in DSpace on 2016-04-27T18:12:25Z (GMT). No. of bitstreams: 1 Priscila Feliciano de Oliveira.pdf: 298919 bytes, checksum: d19d00fc10c4a2440c760088e47f3528 (MD5) Previous issue date: 2007-10-10 / Introduction: Continuous exposure to loud sound pressure levels can cause noise-induced hearing loss (NHIL) and consequently affect the quality of life for these subjects. The handicap of hearing loss has a psychological effect characterized by isolation, stress, difficulties with family relationships, anxiety, sleep difficulties, less confidence and depression. Objective: This research shows the handicap of nourishing branch workers, intent juice workers and cement workers with noise induced hearing loss. Methods: An anamnese and a questionnaire of the handicap scale named Hearing Handicap Inventory for Adults (HHIA) were administered to 72 workers. The subjects were 23 to 58 years old and the mean age at which exposed to occupational noise was 14,5 years. Results: In 72 workers, 21 (29,2%) had handicap presence. The led/moderate auto-perception was shown in 10 (13,9%) workers and severe/significant was shown in 11 people (15,3%). In social/situational scale, the main complaints were using less telephone (38,9%), difficulties to hearing/understanding business colleagues (34,7%) and watching TV and listening to the radio (33,3%). In emotional scale 33,3% were irritated, 30,6% were bored of having difficulties in hearing and 27,8% were constrained or felt sad when they were presented to someone new. In audiograms analysis, the most affected frequency was in the range of 3 to 8 kHz, with worse thresholds in 4 kHz. The relationship between hearing loss and handicap presence was not shown. Conclusion: The handicap presence was observed in 29,2% and there did not appear to be a significant statistical difference between handicap and age, time of noise exposure, tinnitus, and hearing loss / Introdução: A exposição continuada a elevados níveis de pressão sonora podem ocasionar uma perda auditiva induzida por ruído (PAIR) e conseqüentemente provocar efeitos na qualidade de vida do indivíduo. O handicap decorrente de uma perda auditiva é uma alteração psicossocial caracterizada por isolamento, estresse, dificuldades nas relações familiares, ansiedade, dificuldade de sono, diminuição da auto-estima e depressão. Objetivo: Este estudo avaliou a auto-percepção do handicap auditivo decorrente de PAIR em trabalhadores do segmento alimentício e da produção de cimento no Estado de Sergipe. Método: A amostra foi composta por 72 trabalhadores na faixa etária de 23 a 58 anos e com tempo médio de exposição a ruído de 14,5 anos. Foram utilizados um protocolo de anamnese e o questionário de auto-percepção de handicap auditivo- Hearing Handicap Inventory for Adults (HHIA). Resultados: Dos 72 trabalhadores, 21 (29,2%) apresentaram presença handicap auditivo. A auto-percepção de grau leve/moderado foi encontrada em 10 (13,9%) sujeitos e de grau severo/significativo em 11 sujeitos (15,3%).Na escala social/situacional, as principais queixas foram utilizar menos o telefone (38,9%), dificuldades para ouvir/entender os colegas de trabalho (34,7%) e para assistir TV e ouvir rádio (33,3%). Na escala emocional 33,3 % ficam irritados, 30,6% ficam chateados por apresentar dificuldades em ouvir e 27,8% ficam constrangidos ou sem jeito quando são apresentados a pessoas estranhas. Na análise dos audiogramas, o maior comprometimento foi na faixa de freqüência de 3 a 8kHz com piores limiares em 4 kHz. Não foi observada relação da perda auditiva com a presença de handicap. Conclusões: A presença de auto-percepção de handicap auditivo foi de 29,2% e não houve diferença estatisticamente significante entre o handicap a as variáveis idade, tempo de exposição ao ruído, zumbido e grau de perda auditiva

Made available in DSpace on 2016-04-27T18:12:43Z (GMT). No. of bitstreams: 1 ADRIANA SOARES ALVES.pdf: 924579 bytes, checksum: 2f204404494bf32fb7678a29fc64cb3e (MD5) Previous issue date: 2010-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: Continuous exposition to high levels of sonorant pressure can cause a noise induced hearing loss (NIAL) and consequently provoque negative effects on the individual quality of life. Objective: Analysing the hearing handicap auto-perception on textile industry employees with and without noise induced hearing loss. Method: The transversal type of the epidemiological study sample was constituted by 83 employees, being 54 from the Normal Group and 29 from the NIAL group. The age group varyed from 23 to 62 years old. All the employees had been exposed to an occupational noise above 85dB(A) at least for two years. A brief question protocol and the questionnaire about hearing handicap auto-perception named Hearing Handicap Inventory for Adults (HHIA) have been used. Results: 27.8% of the Normal Group employees presented an audiometric notch in one ear at least. The highest frequency was 6kHz. In the NIAL Group the hearing losses were from 3kHz to 8kHz in the right ear, and from 2kHz to 8kHz in the left ear. 24.1% of the NIAL group presented a light / moderate handicap. The Normal Group employees did not present hearing handicap. There was a statiscally significant association between an auto-reporting hearing loss and being part of the NIAL group.Conclusion: Despite the low rate of handicap in the HHIA, the high occurrence of hearing complaints indicates the importance of the studies about noise effects, independently of the hearing loss presence / Introdução: A exposição continuada a elevados níveis de pressão sonora pode ocasionar uma perda auditiva induzida por ruído (PAIR) e, conseqüentemente, provocar efeitos na qualidade de vida do indivíduo. Objetivo: analisar a auto-percepção do handicap auditivo em trabalhadores de uma indústria têxtil com e sem a presença de perda auditiva induzida por ruído. Método: A amostra do estudo epidemiológico do tipo transversal foi composta por 83 funcionários, sendo 54 do grupo Normal e 29 do grupo PAIR. A faixa etária variou de 23 a 62 anos. Todos os trabalhadores estavam expostos a ruído ocupacional acima de 85 dB(A) há, no mínimo, dois anos. Foram utilizados um breve protocolo de anamnese e o questionário de auto-percepção de handicap auditivo denominado Hearing Handicap Inventory for Adults ( HHIA). Resultados: No Grupo Normal, 27,8% apresentaram entalhe audiométrico em pelo menos uma orelha. A freqüência mais acometido foi 6 kHz. No Grupo PAIR, as perdas auditivas foram entre 3 kHz a 8 kHz na orelha direita e entre 2 kHz e 8 kHz na orelha esquerda. Foi identificado handicap de grau leve/moderado em 24,1% do Grupo PAIR. Os trabalhadores do Grupo Normal não apresentaram handicap auditivo. Houve associação estatisticamente significante entre auto-referir perda auditiva e pertencer ao Grupo PAIR. Conclusão: Apesar do baixo índice de handicap no HHIA, a alta ocorrência de queixas auditivas indica a importância de estudos sobre os efeitos do ruído, independente da presença de perda auditiva

INTRODUÇÃO: A exposição a níveis elevados de pressão sonora é a segunda causa mais comum de perda auditiva sensorioneural adquirida. Está relacionada à morte celular por apoptose, necrose e/ou necrose programada (necroptose) devido ao dano mecânico e/ou metabólico, ocasionando a degeneração de estruturas cocleares como células ciliadas, sobretudo externas, células de suporte e de fibras aferentes do nervo coclear. Estudos têm demostrado um aumento na citocina inflamatória TNFa após a exposição ao ruído, bem como a melhoria auditiva relacionada ao uso de etanercepte, que é um bloqueador destacitocina. Neste contexto, este estudo teve por objetivo avaliar o efeito do silenciamento gênico do Tnfa na audição de ratos Wistar, expostos ao ruído branco, e identificar o perfil de expressão gênica na via metabólica desse gene. METODOLOGIA: Foram incluídos ratos Wistar do sexo masculino, jovens com limiar auditivo no Peate clique de 50 dBSPL. Os animais foram submetidos à introdução do siRNA Tnfa em uma orelha, e siRNA scramble na orelha contralateral por via trans-timpânica com posterior exposição à 120 dBSPL de ruído branco por 3h. Foi realizado Peate clique e remoção das cócleas para obtenção do cDNA e avaliação da expressão gênica da via metabólica do Tnfa por meio de qRT-PCR. Um grupo de animais, não submetidos ao silenciamento, foi exposto ao ruído para análise dessa via metabólica. Para o cálculo da expressão gênica relativa (Rq) utilizamos o método do deltaCT comparativo e o teste t-Student pareado para avaliar os parâmetros no Peate clique. RESULTADOS: A taxa de silenciamento observada foi de 74,1%. A média do limiar eletrofisiológico nas orelhas silenciadas foi estaticamente melhor que a orelha scramble (p < 0,001) com valores médios de 49,5 +- 10.5. A amplitude média da onda I em 80 dBSPL e das ondas II e IV em 90 dBSPL foi estatisticamente maior na orelha siRNA Tnfa, sem alteração na latência nas intensidades audíveis,para ambos os lados. A exposição ao ruído promoveu aumento da expressão do gene Tnfa e de seu receptor Tnfrsf1A, 24h após à exposição, associado ao aumento da expressão de genes relacionados à apoptose e diminuição de genes relacionados à sobrevida celular. CONCLUSÃO: O ruído promoveu aumento de expressão do gene Tnfa e de genes envolvidos na apoptose, associado à perda auditiva em modelo experimental. A administração trans-timpânica do siRNA Tnfa promoveu preservação do limiar eletrofisiológico e da amplitude da onda I, II e IV no Peate clique, após exposição ao ruído intenso, sugerindo que a inibição deste pode ser uma estratégia de preservação auditiva promissora. O silenciamento do Tnfa inibiu a disfunção coclear após estímulo acústico, sugerindo que esta proteína é um dos principais agentes envolvidos na perda auditiva induzida pelo ruído, devendo ser considerada como alvo terapêutico na estratégia de preservação auditiva / INTRODUCTION: Exposure to high levels of sound pressure is the second most common cause of acquired sensorineural hearing loss. It is related to cell death through apoptosis, necrosis and/or programmed necrosis (necroptosis) due to mechanical and/or metabolic damage, causing the degeneration of cochlear structures, such as cilliary cells, mainly external, as well as support cells and afferent fibers of the cochlear nerve. Studies have demonstrated an increase in the inflammatory cytokine TNFalfa after exposure to noise, as well as auditory improvement related to the use of etanercept, a cytokine blocker. In this context, this study aimed to evaluate the effect of Tnfa gene silencing on the hearing of Wistar rats exposed to white noise and to identify the expression profile in the metabolic pathway of this gene. METHODOLOGY: Young male Wistar rats with 50 dBSPL threshold in auditory brainstem responses click (ABR) were included in this study and submitted to the introduction of the TnfasiRNA in one ear and the scramble siRNA in the contralateral ear by trans-tympanic route, with subsequent exposure to 120 dB SPL of white noise for 3h. ABR was measured and the cochleae were dissected and used for the extraction of total RNA to obtain cDNA and conduct evaluations of the Tnfa metabolic pathway gene expression by qRT-PCR. A group of animals, not submitted to silencing, was exposed to noise to analyze this metabolic pathway. The relative gene expression (Rq) was calculated by the comparative deltaCT method and the paired Student t-test were applied to evaluate the parameters of the ABR click. RESULTS: The silencing rate was 74.1%. The mean electrophysiological threshold in the silenced ears was statistically higher than the scrambled ear (p < 0.001) with mean values of 49.5 +- 10.5. The mean amplitudes of wave I at 80 dBSPL and waves II and IV at 90dBSPL were statistically higher in the TnfasiRNA ear, with no change in latency at audible intensities for both sides. Noise exposure promoted increased expression of the Tnfa gene and its receptor, Tnfrsf1A, 24h after exposure, associated with increased expression of genes related to apoptosis and decreased expression of genes related to cell survival. CONCLUSIONS: Noise exposure promoted increased in Tnfa gene expression as well as in genes involved in apoptosis, associated with hearing loss in an experimental model. The trans-tympanic administration of TnfasiRNA promotes the preservation of the electrophysiological threshold and the amplitude of wave I, II and IV in the ABR click, after exposure to intense noise, suggesting that this inhibition may be a promising auditory preservation strategy. The Tnfa knockdown inhibited cochlear dysfunction after acoustic injury, suggesting that this protein plays an important role in noise induced hearing loss and should be considered a therapeutic target in auditory preservation strategies

Submitted by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-07-13T13:07:53Z No. of bitstreams: 1 Diss FinaL. Tatiane Meira.2015.pdf: 1405490 bytes, checksum: dfc6231ff4ce6b1dcb27ea991d10b355 (MD5) / Approved for entry into archive by Maria Creuza Silva (mariakreuza@yahoo.com.br) on 2015-07-13T14:40:56Z (GMT) No. of bitstreams: 1 Diss FinaL. Tatiane Meira.2015.pdf: 1405490 bytes, checksum: dfc6231ff4ce6b1dcb27ea991d10b355 (MD5) / Made available in DSpace on 2015-07-13T14:40:56Z (GMT). No. of bitstreams: 1 Diss FinaL. Tatiane Meira.2015.pdf: 1405490 bytes, checksum: dfc6231ff4ce6b1dcb27ea991d10b355 (MD5) / Objetivo: Identificar fatores associados ao uso do equipamento de proteção auditiva (EPA) no trabalho e suas diferenças entre homens e mulheres. Métodos: Estudo transversal realizado com uma amostra aleatória de subáreas de base domiciliar, da cidade de Salvador, Bahia, Brasil. Questionários foram aplicados para a obtenção de dados sociodemográficos, ocupacionais e de saúde. Foram considerados expostos ao ruído aqueles que relataram trabalhar em local onde era necessário gritar para ser ouvido. Os trabalhadores expostos foram questionados sobre o uso e regularidade do uso do EPA. A análise foi conduzida separadamente por sexo, estimando-se a prevalência do uso do EPA, razões de prevalência e os respectivos intervalos de confiança. Resultados: Foram identificados 2.429 trabalhadores entre 18 e 65 anos, dos quais 299 (12,3%) referiram trabalhar expostos ao ruído. A prevalência do uso do EPA foi 59,3% e 21,4%, para homens e mulheres, respectivamente. Entre os homens, apenas o maior nível socioeconômico (razão de prevalência, RP = 1,47; intervalo de confiança, IC95% 1,14;1,90) e ter realizado audiometria (RP = 1,47; IC95% 1,15;1,88) foram fatores associados ao uso do EPA. Em contraste, entre as mulheres, a percepção de um melhor clima de segurança se associou ao uso do EPA (RP = 2,92; IC95% 1,34;6,34), especialmente, ter supervisores comprometidos com a segurança (RP = 2,09; IC95% 1,04;4,21;), a existência de regras claras para evitar acidentes de trabalho (RP = 2,81; IC95% 1,41;5,59) e receber informações sobre a segurança no trabalho (RP = 2,42; IC95% 1,23;4,76). Conclusão: Os resultados deste estudo mostram que há um viés de gênero em relação ao uso do EPA, menos favorável às mulheres em comparação com os homens; e indicam que o uso do EPA entre mulheres é influenciado positivamente pelo clima de segurança, sugerindo que o gênero precisa ser considerado nos programas de conservação auditiva.

Noise is the most common harmful physical agent found in the workplace. This hazardous agent gains more importance when it is proved that the hearing damage caused by it is irreversible, and that the continuous exposure produces other organic, physiological and psycho-emotional disturbances that result in lower life quality and health of workers. This work evaluated the degree of hearing loss and life quality related to the workers health exposed to occupational noise. A total of 110 male workers between 22 and 58 years old were evaluated, with time exposure to occupational noise varying between 3 and 28 years. The workers were submitted to an audiometric evaluation, answered a semi-structured survey and filled in a life quality quiz SF-36. Noise-Induced Hearing Loss (NIHL) was classified according to the diagnostic criteria proposed by Fiorini (1994). Out of the total, 87 (79.1%) presented hearing conditions within normal standards (Group 1) and 23 (20.9%) were classified as suggestive to NIHL (Group 2). Among the 87 audiograms from Group 1, 47 (54%) were within normal standards without loss, and 29 (33%) with unilateral loss. Out of the 23 audiograms from Group 2, 19 (82.6%) were suggestive of bilateral HLIN. In the semi-structured survey, the main complaints from Groups 1 and 2, respectively, were: (95.4%) and (95.7%), considered the workplace to be noisy and had difficulties hearing/understanding others (85%) and (82.6%). Every worker stated that they use safety equipment for the ears. There has not been found a connection between the exposure to noise at the workplace and bad life quality independently of the presence of hearing loss, comparing the dominants as well as the mental and physical components. There has been a relatively high rate of hearing loss, however, the presence of it associated or not to a noisy workplace did not determine a bad global life quality. / O ruído é o agente físico nocivo mais comum encontrado no ambiente de trabalho. Este agente pernicioso ganha maior importância quando se constata que o dano auditivo por ele ocasionado é irreversível, e que a exposição continuada produz outros distúrbios orgânicos, fisiológicos e psicoemocionais que resultam em diminuição da qualidade de vida e de saúde dos trabalhadores. Este estudo avaliou o impacto do ruído ocupacional na audição e qualidade de vida de trabalhadores inseridos em um programa de conservação auditiva. Foram avaliados 110 trabalhadores, do sexo masculino, com idades entre 22 a 58 anos, com tempo de exposição ao ruído ocupacional variando entre três e 28 anos. Os sujeitos realizaram avaliação audiométrica, responderam a um questionário semi-estruturado e preencheram o questionário de qualidade de vida SF-36. A Perda Auditiva Induzida por Ruído (PAIR) foi classificada segundo o critério diagnóstico proposto por Fiorini (1994). Do total, 87 (79,1%) apresentaram audição dentro dos padrões de normalidade (Grupo 1) e 23 (20,9%) foram classificados como sugestivos de PAIR (Grupo 2). Dentre os 87 audiogramas do Grupo 1, 47 (54%) foram dentro da normalidade sem entalhe, e 29 (33%) com entalhe unilateral. Dos 23 audiogramas do Grupo 2, 19 (82,6%) foram sugestivos de PAIR bilateral. No questionário semiestruturado, as principais queixas dos Grupos 1 e 2, respectivamente, foram: (95,4%) e (95,7%) consideram o ambiente de trabalho ruidoso e dificuldade de ouvir/entender as outras pessoas (85%) e (82,6%). Todos os trabalhadores relataram utilizar protetor auditivo. Não foi observada relação entre a exposição ocupacional ao ruído e má qualidade de vida independente da presença de perda auditiva, comparando tanto os domínios, quanto os componentes físico e mental. Houve uma taxa relativamente alta de perda auditiva, no entanto a presença da mesma associada ou não ao ruído ocupacional não determinou uma má qualidade de vida global.

In individuals claiming compensation for occupational noise induced hearing loss, a population with a high incidence of nonorganic hearing loss, a reliable and valid behavioural pure tone (PT) threshold is not always achievable. Recent studies have compared the accuracy of behavioural PT threshold estimation using the slow cortical auditory evoked potentials (SCAEP) and auditory steady-state responses (ASSR) but there is no consensus regarding recommended technique. A review of the literature indicated that no comparison has been completed on the use of SCAEP and a single frequency ASSR technique. A research project was therefore initiated with the aim of comparing the clinical effectiveness (accuracy) and clinical efficiency (time required) of SCAEP and ASSR for behavioural PT threshold estimation in adults exposed to occupational noise. Adult participants were divided into a group with normal hearing (behavioural PT thresholds < 20 dBHL; n = 15) and a group of participants with hearing loss (n = 16 adults), the latter of which were recruited from individuals referred for audiometric screening, as part of hearing conservation programs, and who were, therefore, exposed to occupational noise. The GSI Audera electrophysiological system was used for both SCAEP and ASSR threshold measurement at 0.5, 1, 2 and 4 kHz. Use was made of tone burst stimuli for the SCAEP (rise and fall of 10 ms with 80 ms plateau), while amplitude and frequency modulated (AM/FM) stimuli was used during ASSR testing. The system’s 40 Hz protocol was chosen for use during ASSR recording while participants slept because this led to lparticipants. ASSR thresholds could not be measured in two of the three sleeping participants in the preliminary study using an 80 Hz modulation rate due to excessive noise. The mean SCAEP difference scores (SCAEP threshold minus behavioural PT threshold) for both participant groups were -0.2+10.2, 2.8+10.1,5.8+9.7, 0.5+10.4 at 0.5, 1, 2, and 4 kHz respectively, while ASSR difference scores were 25.3+12.8, 21.7+11.3,32.3+12.2, 27.1+13.8. The SCAEP correlations with behavioural PT thresholds across frequencies (r = 0.85) were also stronger than ASSR correlations (r = 0.75). Therefore, with regard to proximity of auditory evoked potentials (AEP) to behavioural PT thresholds and consistency of this relationship, the SCAEP, rather than ASSR, is the AEP of choice. However, the SCAEP took on average 10.1 minutes longer to complete than the ASSR. Clinical effectiveness was given comparably more weight than the clinical efficiency of the AEP technique to estimate behavioural PT thresholds due to the impact on overcompensation for occupational noise induced hearing loss. As such, the study acknowledged the SCAEP as the AEP of choice for the purpose of behavioural PT thresholds in adults exposed to occupational noise. It is important to note that the conclusion reached in the current study arose from the comparison of the SCAEP with a specific ASSR technique. Accuracy of ASSR estimation of behavioural PT thresholds is strongly influenced by stimulus and recording parameters of the system used, and by the participant variables. Copyright / Dissertation (MCommunication Pathology)--University of Pretoria, 2010. / Speech-Language Pathology and Audiology / Unrestricted

This study focused on designing a training programme for audiometricians, using the principles of instructional design. Instructional design is the continuing, systematic development of instructional specifications, utilizing researched strategies and principles to create detailed outcomes for the development, implementation, evaluation and maintenance of training programmes. An audiometrician is defined by SANS (10083:2004), as a person registered with the Health Professions Council of South Africa as an audiometrician, hearing aid acoustician or someone trained in audiometry. Audiometricians are adult learners. Therefore, in addition to instructional design principles, the principles of adult learning were also incorporated in the training programme. The successful training of audiometricians may ensure that noise induced hearing loss is significantly reduced when audiometric monitoring is appropriately implemented as part of a hearing conservation programme. Training for audiometricians is critical in this process as incorrect audiometric monitoring may negatively influence the outcomes of a hearing conservation programme. This study followed a descriptive research design where the results were described in a quantitative manner. Data was collected by means of electronically mailed questionnaires. All participants were practicing audiometricians at the time of the study and were registered with the South African Society for Occupational Health Nursing. All participants had an audiometric certificate as qualification. For the analysis of data, 181 completed questionnaires were used. The results were analyzed and described in terms of the respondents’ own experience regarding audiometry; their opinions regarding the topics they have been taught in audiometry; the duration of their own training programmes and their opinions regarding a future training programme for audiometricians. Based on the results of the above analysis, the instructional design programme for audiometricians was developed. The obtained results were used to determine what the topics, content, duration, learning outcomes and learner evaluation methods should be in the development of a training programme for audiometricians. This research study developed a training programme for audiometricians in order to ensure that all future audiometricians have the necessary knowledge to perform comprehensive hearing evaluations, interpret audiometric findings and thereby assist in reducing noise induced hearing loss in the industrial sector through hearing conservation programmes. AFRIKAANS : Hierdie studie is toegespits op die ontwerp van ‘n onderrigprogram vir oudiometriste waarin die beginsels van onderrigontwerp toegepas is. Onderrigontwerp behels die deurlopende en stelselmatige ontwikkeling van onderrigspesifikasies deur gebruik te maak van nagevorsde strategieë en beginsels om gedetailleerde uitkomste vir die ontwikkeing, evaluering en onderhoud van opleidingsprogramme daar te stel. ‘n Oudiometris word gedefinieer deur wetgewing (SANS 10083:2004) as ‘n person wat geregistreer is by die Health Professions Council of South Africa as ‘n oudiometris, gehoorapparaat akoestikus of iemand wat opgelei is in oudiometrie. Oudiometriste is volwasse leerders. Om hierdie rede is nie net die beginsels van onderrigontwerp nie, maar ook die beginsels van volwasse leer in die onderrigprogram geïnkorporeer. Suksesvolle onderrig van oudiometriste kan verseker dat die voorkoms van geraas-geïnduseerde gehoorverlies verminder, mits oudiometriese monitering toepaslik as deel van ‘n program vir gehoorkonservering geïntegreer word. Opleiding vir oudiometriste is krities belangrik in hierdie proses want indien oudiometriese monitering verkeerd gedoen word, kan dit die gehoorkonserveringsprogram in totaliteit negatief beïnvloed. ‘n Beskrywende navorsingsontwerp is in hierdie studie gebruik en die resultate is kwantitatief beskryf. Data is deur middel van vraelyste wat elektronies versend is, versamel. Al die deelnemers was ten tye van die studie praktiserende oudiometriste wat by die South African Society for Occupational Health Nursing geregistreer was. Elkeen was in besit van ‘n oudiometriese sertifikaat as kwalfikasie. Vir data-ontleding is 181 voltooide vraelyste gebruik. Die data was geanaliseer en beskryf in terme van die respondente se eie ervaring ten opsigte van oudiometrie; hul mening omtrent die temas wat by hul opleiding ingesluit was; die duur van hul opleidingsprogramme en hul idees omtrent ‘n toekomstige opleidingsprogram vir oudiometriste. Die onderrigontwerp-program is op grond van die resultate van bognoemde analise ontwikkel. Die resultate wat verkry is, is gebruik om die temas, inhoud, duur, leeruitkomste en evalueringsmetodes in die ontwikkeling van ‘n opleidingsprogram vir oudiometriste te bepaal. Hierdie studie is gerig op die ontwikkeling van ‘n opleidingsprogram vir oudiometriste met die doel om te verseker dat hulle oor die nodige kennis beskik om omvattende gehoorevaluerings uit te voer, om oudiometriese bevindinge te interpreteer en daardeur, in gesondheidssorgprogramme, by te dra tot die vermindering van geraas-geïnduseerde gehoorverlies in die industriële sektor Copyright / Dissertation (MCommunication Pathology)--University of Pretoria, 2012. / Speech-Language Pathology and Audiology / unrestricted

<div>Hearing loss hinders the communication ability of many individuals despite state-of-the-art interventions. Animal models of different hearing-loss etiologies can help improve the clinical outcomes of these interventions; however, several gaps exist. First, translational aspects of animal models are currently limited because anatomically and physiologically specific data obtained from animals are analyzed differently compared to noninvasive evoked responses that can be recorded from humans. Second, we lack a comprehensive understanding of the neural representation of everyday sounds (e.g., naturally spoken speech) in real-life settings (e.g., in background noise). This is even true at the level of the auditory nerve, which is the first bottleneck of auditory information flow to the brain and the first neural site to exhibit crucial effects of hearing-loss. </div><div><br></div><div>To address these gaps, we developed a unifying framework that allows direct comparison of invasive spike-train data and noninvasive far-field data in response to stationary and nonstationary sounds. We applied this framework to recordings from single auditory-nerve fibers and frequency-following responses from the scalp of anesthetized chinchillas with either normal hearing or noise-induced mild-moderate hearing loss in response to a speech sentence in noise. Key results for speech coding following hearing loss include: (1) coding deficits for voiced speech manifest as tonotopic distortions without a significant change in driven rate or spike-time precision, (2) linear amplification aimed at countering audiometric threshold shift is insufficient to restore neural activity for low-intensity consonants, (3) susceptibility to background noise increases as a direct result of distorted tonotopic mapping following acoustic trauma, and (4) temporal-place representation of pitch is also degraded. Finally, we developed a noninvasive metric to potentially diagnose distorted tonotopy in humans. These findings help explain the neural origins of common perceptual difficulties that listeners with hearing impairment experience, offer several insights to make hearing-aids more individualized, and highlight the importance of better clinical diagnostics and noise-reduction algorithms. </div>