Comparison of Sudden Sensorineural Hearing Loss with Tinnitus and Short-Term Tinnitus

Objective. As one of the common symptoms of sudden sensorineural hearing loss (SSH), tinnitus seriously affects the life and work of SSH patients. The present study is aimed at exploring whether SSH can receive acoustic therapy and the factors that affect the efficacy of SSH acoustic therapy. Methods. A total of 162 patients were outpatients and inpatients, 86 were SSH, and 76 were short-term tinnitus (STT). Both groups received pure tone audiometry, tinnitus matching, and residual inhibition test (RI). The Tinnitus Handicap Inventory (THI), visual analog scale with respect to tinnitus loudness (VAS), and RI in each group were evaluated. The effects of age, degree of hearing loss, and tinnitus course on the efficacy of SSH acoustic therapy were also evaluated. Results. In the comparison of RI, THI, and VAS, there was no difference between SSH and STT ( P > 0.05 ). SSH patients with mild hearing loss showed better acoustic therapy efficacy compared with SSH patients with severe hearing loss ( P < 0.05 ), but there is no statistical difference in age and the course of tinnitus ( P > 0.05 ). Conclusion. The present study showed that SSH may improve tinnitus symptom through receiving acoustic therapy and SSH patients with mild hearing loss can get better acoustic therapy effects.

Prediction of Acoustic Residual Inhibition of Tinnitus Using a Brain-Inspired Spiking Neural Network Model

Auditory Residual Inhibition (ARI) is a temporary suppression of tinnitus that occurs in some people following the presentation of masking sounds. Differences in neural response to ARI stimuli may enable classification of tinnitus and a tailored approach to intervention in the future. In an exploratory study, we investigated the use of a brain-inspired artificial neural network to examine the effects of ARI on electroencephalographic function, as well as the predictive ability of the model. Ten tinnitus patients underwent two auditory stimulation conditions (constant and amplitude modulated broadband noise) at two time points and were then characterised as responders or non-responders, based on whether they experienced ARI or not. Using a spiking neural network model, we evaluated concurrent neural patterns generated across space and time from features of electroencephalographic data, capturing the neural dynamic changes before and after stimulation. Results indicated that the model may be used to predict the effect of auditory stimulation on tinnitus on an individual basis. This approach may aid in the development of predictive models for treatment selection.

Susceptibility to Residual Inhibition Is Associated With Hearing Loss and Tinnitus Chronicity

Residual inhibition, that is, the temporary suppression of tinnitus loudness after acoustic stimulation, is a frequently observed phenomenon that may have prognostic value for clinical applications. However, it is unclear in which subjects residual inhibition is more likely and how stable the effect of inhibition is over multiple repetitions. The primary aim of this work was to evaluate the effect of hearing loss and tinnitus chronicity on residual inhibition susceptibility. The secondary aim was to investigate the short-term repeatability of residual inhibition. Residual inhibition was assessed in 74 tinnitus subjects with 60-second narrow-band noise stimuli in 10 consecutive trials. The subjects were assigned to groups according to their depth of suppression (substantial residual inhibition vs. comparator group). In addition, a categorization in normal hearing and hearing loss groups, related to the degree of hearing loss at the frequency corresponding to the tinnitus pitch, was made. Logistic regression was used to identify factors associated with susceptibility to residual inhibition. Repeatability of residual inhibition was assessed using mixed-effects ordinal regression including poststimulus time and repetitions as factors. Tinnitus chronicity was not associated with residual inhibition for subjects with hearing loss, while a statistically significant negative association between tinnitus chronicity and residual inhibition susceptibility was observed in normal hearing subjects (odds ratio: 0.63; p = .0076). Moreover, repeated states of suppression can be stably induced, reinforcing the use of residual inhibition for within-subject comparison studies.

EVALUTION OF ANTIMICROBIAL ACTIVITY OF PARTIAL PURIFIED BACTERIOCIN FROM LOCAL ISOLATE OF BACILLUS LICHENIFORIMS HJ2020 MT192715.1

This study was aimed to produce bacteriocin from Bacillus. licheniformis isolated from local soil of corn and sunflower fields and using as antimicrobial agent . Fourteen of local isolates of Bacillus sp. were obtained and ability of these isolates for growth on Brain heart infusion agar (BHI) at 550C were tested. Isolate C4 was revealed high growth density in comparison with other isolates. Isolate C4 was identified as Bacillus licheniformis according to morphological, cultural and biochemical tests, Moreover genetic analysis for 16S rRNA gene and given accession number MT192715.1 in GenBank of NCBI . Production of bacteriocin from this isolate was carried out in Luria Broth (LB) and partially purified by precipitation with 30-70 % saturation of ammonium sulfate followed by concentrated using poly ethylene glycol (PEG).The antimicrobial activity of partially purified bacteriocin was assayed against many species of food spoilage microorganism. Results were revealed that anitimicrobial activity of bacteriocin were between (0 - 360 ) units / ml. Stability of antimicrobial activity of partially purified bacteriocin toward Staphylococcus aureus were tested after incubation at different values of pH, temperature and some of enzyme which included proteolytic enzymes, α-amylase and lipase .The results indicated that residual inhibition activity of bacteriocin were varied according to conditions of incubation and type of treatment .

Neurophysiological correlates of residual inhibition in tinnitus: Hints for trait-like EEG power spectra

Magneto- and electroencephalography (M/EEG) investigations in tinnitus patients demonstrated anomalous oscillatory brain activity patterns compared to healthy controls. A well-established phenomenon in tinnitus is the possibility to temporary suppress tinnitus following acoustic stimulation, which is termed residual inhibition (RI). The few former neurophysiological investigations of RI reported partly conflicting results hampering consensus on tinnitus-specific brain activity and basic neural models.Hence, our objective was to investigate RI-specific oscillatory brain activity changes and whether these changes can be associated with behavioral measures of tinnitus loudness. Further, contrasts between acoustic stimulation responders and non-responders provide further insights in RI-related spontaneous brain activity.Three different types of noise stimuli were administered for acoustic stimulation in 45 tinnitus patients. Subjects resting state brain activity was recorded before and during RI via EEG alongside with subjective measurements of tinnitus loudness.On the whole-group level, tinnitus-unspecific changes were observed which fit established knowledge about basic neural responses after acoustic stimulation. Responder non-responder contrasts revealed differences in alpha and gamma band activity in line with the proposed neural models for oscillatory brain activity in tinnitus. Further analysis of sample characteristics demonstrated divergences between responders and nonresponders notably for tinnitus duration. During RI, distinct differences between responders and non-responders were exclusively observed for alpha band activity in auditory cortical areas. Neither correlations of behavioral tinnitus measures nor differences between stimulus-induced changes in ongoing brain activity could be detected.Taken together, our observations might be indicative of trait-specific forms of oscillatory signatures in different subsets and chronification grades of the tinnitus population possibly related to acoustic tinnitus suppression. Results and insights are not only useful to understand basic neural mechanisms behind RI but are also valuable for general neural models of tinnitus.HighlightsResidual inhibition provides a key method to study the basic mechanisms of tinnitus.We compared residual inhibition EEG activity between responders and non-responders.In responders, the alpha activity in auditory areas was increased during tinnitus suppression.Results and insights are valuable for understanding the neural mechanisms behind acoustic tinnitus suppression.

Susceptibility to Residual Inhibition is Associated with Hearing Loss and Tinnitus Chronicity

Residual inhibition, i.e. the temporary suppression of tinnitus loudness after acoustic stimulation, is a frequently observed phenomenon that may have prognostic value for clinical applications. However, it is unclear in which subjects residual inhibition is more likely and how stable the suppression can be induced repeatedly. The primary aim of this work was to evaluate the effect of hearing loss and tinnitus chronicity on residual inhibition susceptibility. The secondary aim was to investigate the short-term repeatability of residual inhibition. Residual inhibition was assessed in 74 tinnitus subjects with 60-second narrow-band noise stimuli in 10 consecutive trials. The subjects were assigned to groups according to their depth of suppression (substantial residual inhibition vs. comparator group). In addition, a categorization in normal hearing and hearing loss groups, related to the degree of hearing loss at the frequency corresponding to the tinnitus pitch, was made. Logistic regression was used to identify factors associated with susceptibility to residual inhibition. Repeatability of residual inhibition was assessed using mixed-effects ordinal regression including post-stimulus time and repetitions as factors. Tinnitus chronicity was not associated with residual inhibition for subjects with hearing loss, while a statistically significant negative association between tinnitus chronicity and residual inhibition susceptibility was observed in normal hearing subjects (odds ratio: 0.63; CI: 0.41 to 0.83; p = 0.0076). Moreover, repeated states of suppression can be stably induced. Our results suggest that long chronicity and residual inhibition susceptibility could be indicators for hidden lesions along the auditory pathway in subjects with normal hearing thresholds at their tinnitus frequency.