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Objectives: Noise-induced hearing loss (NIHL) may result from occupational noise exposures and is considered as an 'Occupational Disease'; therefore, it is compensable. To verify the existence and severity of the work-related hearing loss, there is a need of an objective, reliable auditory measure in cases of arbitration of financial disputes to resolve any medicolegal aspects. The objective of the study was to compare between the ABR and ASSR for predicting the behavioural threshold in subjects with normal hearing or NIHL. Design: The study included 82 subjects regularly exposed to high levels of occupational noise, with normal hearing and NIHL. ABR to clicks and to tone bursts were recorded followed by multiple-frequency ASSR. Physiological and behavioural thresholds were compared for specific frequencies (1000, 2000 Hz) and average of high-frequency range (2000 and 4000 Hz). In addition, Pearson correlations and the specificity and sensitivity of each measure were also calculated using receiver operating characteristic (ROC) curves. Results: In the NIHL group, there was a significantly smaller difference between the behavioural threshold and click-ABR than the ASSR in high-frequency range. Pearson correlations were significantly higher for click-ABR. Analysis of specific frequencies yielded a smaller difference between behavioural and ASSR than tone-burst-ABR thresholds, with a slightly better correlation for ASSR than tone-burst- ABR. Higher sensitivity but lower specificity was suggested for ASSR than ABR. Conclusions: ASSR is associated with high-frequency specificity, shorter test sessions and good correlations with behavioural thresholds, making it a potentially better measure than ABR for predicting audiograms in subjects with NIHL. These findings have diagnostic implications, especially in cases of workers' compensation when subjects may be uncooperative. [ABSTRACT FROM AUTHOR]

Nageris BI, Ulanovski D, Attias J. Ann Otol Rhilol Laryngol 2004;113:672-675. Magnesium treatment has been repeatedly shown to reduce the incidence of both temporary and permanent noise-induced hearing loss. We [...]

The objective of the study was to investigate the prevalence of congenital and early-onset hearing loss, and the influence of the known risk factors for hearing loss on infants in Jordan and Israel. Subjects were a total of nearly 17000 infants from both countries, including infants with and without risk factors for hearing loss. The hearing screening protocol included distortion product otoacoustic emission, followed in case of repeated OAE referral or high risk (HR) infant by diagnostic auditory brainstem responses. The results indicate that the prevalence and severity of hearing loss amongst Jordanian infants (1.37%) is remarkably higher as compared to the Israeli infants (0.48%). The overall prevalence of bilateral SNHL was seven times more in the Jordanian infants, 18 times in non-risk, and three times in the HR infants relative to the Israeli infants. Risk factors including family history, hyperbilirubinemia, bacterial meningitis, and associated syndromes were more prevalent amongst Jordanian infants. This unique study underscores the importance of sharing and exchanging information to create empirical data to guide health-care providers in adapting protocols to the local constraints in developing countries. [ABSTRACT FROM AUTHOR]

Filtration stress, consisting in the rapid filtration of Acer pseudoplatanus L. cell suspension cultures, resulted in significant differences between the peroxidases (EC 1.11.1.7) released during cell growth and those released after filtered cells were resuspended in fresh medium (recovery medium). These differences concerned mainly modifications of (i) the pH optimum of peroxidase activity (guaiacol as electron donor), (ii) the number and the pI values of the peroxidase isoenzymes as shown by isoelectric focusing, and (iii) the molecular weights of the different peroxidase fractions determined by gel filtration chromatography. The presence of 1 mM Li+ in the recovery medium inhibited the release of peroxidase and this effect was partially reversed by K+. The release of peroxidase by stressed cells was also strongly inhibited by Na2CO3 in the recovery medium. The results presented are consistent with the proposal that the characteristic isoperoxidase patterns induced by filtration stress might be used as a model to study the response of plant cells to stress. [ABSTRACT FROM AUTHOR]

The effect of transdermal scopolamine on salivary flow and composition was analyzed in 21 healthy volunteers. The flow rate of whole saliva was significantly lowered by transdermal scopolamine. Significant positive correlations were found between the placebo rate of flow and both the quantity and percentage decreases in response to transdermal scopolamine. The magnesium concentration was significantly increased during transdermal scopolamine administration, whereas the sodium, potassium, and calcium concentrations were not consistently altered. Accordingly, the magnesium secretion rate was unaltered, whereas sodium, potassium, and calcium secretion rates were significantly lowered by transdermal scopolamine administration. [ABSTRACT FROM AUTHOR]