Leupeptin reduces impulse noise induced hearing loss

<p>Abstract</p> <p>Background</p> <p>Exposure to continuous and impulse noise can induce a hearing loss. Leupeptin is an inhibitor of the calpains, a family of calcium-activated proteases which promote cell death. The objective of this study is to assess whether Leupeptin could reduce the hearing loss resulting from rifle impulse noise.</p> <p>Methods</p> <p>A polyethelene tube was implanted into middle ear cavities of eight fat sand rats (16 ears). Following determination of auditory nerve brainstem evoked response (ABR) threshold in each ear, the animals were exposed to the noise of 10 M16 rifle shots. Immediately after the exposure, saline was then applied to one (control) ear and non-toxic concentrations of leupeptin determined in the first phase of the study were applied to the other ear, for four consecutive days.</p> <p>Results</p> <p>Eight days after the exposure, the threshold shift (ABR) in the control ears was significantly greater (44 dB) than in the leupeptin ears (27 dB).</p> <p>Conclusion</p> <p>Leupeptin applied to the middle ear cavity can reduce the hearing loss resulting from exposure to impulse noise.</p

Inferior Flap Tympanoplasty: A Novel Technique for Anterior Perforation Closure

Objective. To report a novel tympanoplasty modification for anterior tympanic membrane perforation closure. Materials and Methods. A prospective study on 13 patients who underwent inferior tympanoplasty between December 2008 and May 2011 was carried out. In our technique, an inferior rather than a posterior flap is raised and the graft is laid from the inferior direction to obtain better access to the anterior part of the tympanic membrane perforation and provide better support. Results. A total of 13 patients underwent the novel inferior tympanoplasty technique with a mean age of 33 years. Six patients had undergone tympanoplasties and/or mastoidectomies in the past, 3 in the contralateral ear. A marginal perforation was observed in 3 cases, total perforation in 2 and subtotal in 1 case. The mean preoperative pure-tone average was 40.4 dB (10 to 90 dB), compared to 26.5 dB (10 to 55 dB) postoperatively. All perforations were found to be closed but one (92.3% success rate). Conclusions. The inferior tympanoplasty technique provides a favorable outcome in terms of tympanic membrane closure and hearing improvement for anterior perforations, even in difficult and complex cases. It is based on a well-known technique and is easy to implement

Extended High Frequency Audiometry for Revealing Sudden Sensory Neural Hearing Loss in Acute Tinnitus Patients

Introduction The measurement of extended high-frequency (EHF) audiometry has become more popular recently, mainly in connection with ototoxicity and noiseinduced hearing loss. New-onset tinnitus evaluation includes a standard hearing test that shows no pathology. Objective The aim of the present study was to evaluate the possibility that acute tinnitus is essentially connected to sudden sensory neural hearing loss (SSNHL), by utilizing EHF audiometry in cases in which standard audiometry for frequencies between 250 Hz to 8 kHz is within normal limits. Methods A retrospective study was conducted between January 2009 and May 2014 that included all patients presenting with acute tinnitus and normal standard audiometry. All patients underwent EHF audiometry and were treated accordingly. Results Thirty-two patients with acute tinnitus and asymmetric sensorineural hearing loss on EHF audiometry were identified. The average deltas between the ears were between 9.2 and 33dB (worse in the affected ear). Conclusion Extended high-frequency audiometry up to 20,000 Hz should be performed in all patients with acute tinnitus and standard audiometry within normal limits

Peri-implant disease affects systemic complete blood count values-an experimental in vivo study.

OBJECTIVES To assess complete blood count (CBC) dynamics following ligature removal and open flap debridement in experimental peri-implantitis in dogs. MATERIALS AND METHODS Seven male beagle dogs were included in the study. Four rough-surface implants were placed pair-wise in both sides of the mandible 14 weeks after tooth extraction. Second stage surgery was performed after 14 weeks. Experimental peri-implantitis was initiated 3 weeks later by ligature placement around the healing caps thus facilitating plaque accumulation and inducing inflammation and destruction of peri-implant tissues. Ligature removal and open flap debridement were performed 11 weeks later. The CBC values were compared with baseline after each procedure. Wilcoxon paired tests were conducted in order to identify statistically significant differences between baseline data and values obtained after each procedure. RESULTS Following experimental peri-implantitis, statistically significant (p < 0.05) increases were noted for white blood cells-WBC (9.62 ± 4.34 vs. 6.48 ± 1.34 cells per microliter of blood × 1000), hemoglobin-Hb (15.25 ± 0.94 vs. 13.52 ± 1.46, grams per deciliter), red blood cells-RBC (7.26 ± 0.79 vs. 5.9 ± 0.61 cells per microliter of blood × 1000), mean corpuscular hemoglobin-MCH (23.64 ± 0.96 vs. 23.16 ± 0.83 picograms/cell), platelets-PLT (349.86 ± 51.05 vs. 277.57 ± 66 cells per microliter of blood × 1000), and mean corpuscular hemoglobin concentration-MCHC (35.83 ± 0.27 vs. 31.04 ± 0.48 grams per deciliter). A statistically significant (p < 0.05) decrease in values was noted only for after ligature removal and open flap debridement. Mean corpuscular volume-MCV values were significantly lower (65.99 ± 2.31 vs. 74.65 ± 2.85 femtoliter) following 1st ligature. Values returned to baseline after open flap debridement. CONCLUSIONS Within its limits, the present data suggest that experimentally induced peri-implantitis affects CBC values. Following surgical treatment, CBC values returned to normal. Clinical relevance This is the first study suggesting possible relationships between peri-implantitis and CBC values. Future studies, confirming such correlation, may provide an insight into the importance of peri-implant maintenance and treatment to minimize supporting tissues disease and reduce systemic effects

Effects of peri-implant infection on serum biochemical analysis.

BACKGROUND Peri-implant disease (PID) has not been directly linked to pathological organ changes. The present study assessed the dynamics of serum biochemical parameters in a model of experimental peri-implantitis in dogs, followed by open flap debridement. MATERIAL AND METHODS Seven male Beagle dogs comprised the study group. Procedures were performed as follows-extractions of two premolars and one molar on each mandibular quadrant (Day 0); bone healing time (week14); placement of four rough-surface endoosseous implants, two on each mandibular side; implant uncovering (week 28); induction of experimental peri-implantitis by the use of three ligatures (weeks 31, 34, 37) followed by open flap debridement (week 42). Serum biochemical analysis following each procedure was compared to baseline. Biochemical parameters were assigned into four subsets of variables-inflammation, renal function, liver function, and blood glucose. Wilcoxon paired tests were conducted in order to identify statistically significant differences between baseline data and values obtained after each procedure RESULTS: Following experimental peri-implantitis, the dynamics of renal parameters and blood glucose were minimal whereas statistically significant (P < 0.05) increases were noted for inflammatory (total protein and albumin concentrations) and hepatic (ALT, AST) parameters. A statistically significant (P < 0.05) decrease was only noted for total bilirubin. After open flap debridement, inflammatory (total protein and albumin concentrations) and hepatic (AST) parameters returned to baseline. CONCLUSIONS Within their limits, the present results indicate that: (a) PID affects inflammatory and hepatic serum biochemical parameters, and (b) following open flap debridement most of the values returned to baseline

How Patients Percept Their Recovery Following Impacted Mandibular Third Molar Coronectomy

Objectives: To compare the quality of life (QOL), side effects, risks, and complications following mandibular third molar coronectomy compared with conventional third molar extraction

Effects of peri‐implant infection on serum biochemical analysis

BACKGROUND Peri-implant disease (PID) has not been directly linked to pathological organ changes. The present study assessed the dynamics of serum biochemical parameters in a model of experimental peri-implantitis in dogs, followed by open flap debridement. MATERIAL AND METHODS Seven male Beagle dogs comprised the study group. Procedures were performed as follows-extractions of two premolars and one molar on each mandibular quadrant (Day 0); bone healing time (week14); placement of four rough-surface endoosseous implants, two on each mandibular side; implant uncovering (week 28); induction of experimental peri-implantitis by the use of three ligatures (weeks 31, 34, 37) followed by open flap debridement (week 42). Serum biochemical analysis following each procedure was compared to baseline. Biochemical parameters were assigned into four subsets of variables-inflammation, renal function, liver function, and blood glucose. Wilcoxon paired tests were conducted in order to identify statistically significant differences between baseline data and values obtained after each procedure RESULTS: Following experimental peri-implantitis, the dynamics of renal parameters and blood glucose were minimal whereas statistically significant (P < 0.05) increases were noted for inflammatory (total protein and albumin concentrations) and hepatic (ALT, AST) parameters. A statistically significant (P < 0.05) decrease was only noted for total bilirubin. After open flap debridement, inflammatory (total protein and albumin concentrations) and hepatic (AST) parameters returned to baseline. CONCLUSIONS Within their limits, the present results indicate that: (a) PID affects inflammatory and hepatic serum biochemical parameters, and (b) following open flap debridement most of the values returned to baseline