What stress components drive mechanochemistry? A study of ZDDP tribofilm formation.

Zinc dialkyldithiophosphate (ZDDP), the most widely used antiwear additive in engine oils, has been extensively studied over the last few decades to help understand the origin of its effectiveness. Glassy phosphate-based tribofilms, approximately 100 nm thick, are often formed on surfaces sliding in ZDDP-containing oils, which help to prevent or reduce wear. Recent studies reveal that a combination of applied shear and compressive stresses drive mechanochemical reactions that promote tribofilm growth, and that growth is further accelerated by increased temperature.

The profile of otoacoustic emissions and multifrequency tympanometry in otosclerotic patients undergoing two types of stapes surgery: small fenestra and microtraumatic stapedotomy.

Background: Otoacoustic emissions (OAEs) are influenced in otosclerosis. The aim of the current study was to investigate the profile of transient evoked (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) in association with multifrequency tympanometry measures in otosclerotic patients undergoing 2 types of stapes surgery: small fenestra and microtraumatic stapedotomy.

Material And Methods: A retrospective analysis of prospectively collected data was conducted evaluating 51 otosclerotic patients and 50 normal hearing subjects.

Contribution of Vestibular-Evoked Myogenic Potential (VEMP) testing in the assessment and the differential diagnosis of otosclerosis.

Background: The aim of this prospective clinical study was to evaluate the clinical importance of Vestibular-Evoked Myogenic Potentials (VEMPs) in the assessment and differential diagnosis of otosclerosis and otologic diseases characterized by "pseudo-conductive" components. We also investigated the clinical appearance of balance disorders in patients with otosclerosis by correlating VEMP results with the findings of caloric testing and pure tone audiometry(PTA).

Material And Methods: Air-conducted(AC) 4-PTA, bone-conducted(BC) 4-PTA, air-bone Gap(ABG), AC, BC tone burst evoked VEMP, and calorics were measured preoperatively in 126 otosclerotic ears.

A longitudinal study of changes in distortion-product otoacoustic emissions and pure-tone thresholds in an industrial setting.

In a longitudinal study of 76 noise-exposed industrial workers, 34 (68 ears) of them were available for final evaluation after 9 years of observation. Distortion-product otoacoustic emissions (DP) at 65/55 dB SPL and pure-tone audiometry were used to detect noise-induced inner ear changes. Repeated measures analyses of variance were made on the subjects and in a control group, whereas significant threshold shifts (STS) and significant emission shifts (SES) were calculated.

Apogeotropic variant of lateral semicircular canal benign paroxysmal positional vertigo: is there a correlation between clinical findings, underlying pathophysiologic mechanisms and the effectiveness of repositioning maneuvers?

Objective: The apogeotropic variant of horizontal semicircular canal (h-SCC) benign paroxysmal positional vertigo (BPPV) is attributed to canalithiasis of the anterior arm or cupulolithiasis. This study is an attempt to distinguish the most effective maneuvers for each case, by investigating any correlation, between the clinical findings or the treatment options and the possible location of the displaced debris.

Data Sources: A review of the literature (1990-2012) was conducted via the PubMed database with the search terms "apogeotropic nystagmus and benign paroxysmal positional vertigo.

Cochlear dysfunction in patients with acute hypothyroidism.

The effect of acute hypothyroidism on the cochlear function was studied prospectively, in a group of 52 patients with thyroid carcinoma who underwent total thyroidectomy. All patients were examined before surgery and 6-8 weeks postoperatively. During this period there was no replacement with levothyroxine and the magnitude of thyroxin depletion was monitored by serum thyroid-stimulating hormone levels.

Inner ear dysfunction in myotonic dystrophy type 1.

Objectives: Myotonic dystrophy type 1 is associated with various oculomotor, vestibular, and auditory abnormalities. However, auditory system investigation has been mainly performed with the subjective method of pure-tone audiometry. In this study, a detailed vestibular and audiological evaluation was undertaken, including the objective and more sensitive method of transiently evoked otoacoustic emissions (TEOAEs).

Monosymptomatic clinically isolated syndrome with sudden sensorineural hearing loss: case report and critical review of the literature.

Introduction: Isolated cranial nerve involvement is rare in patients with multiple sclerosis (10.4%) and extremely rare is an eighth nerve palsy, especially in the context of a clinically isolated syndrome (<1%).

Case Report: A 34-year-old male presented with a history of left-sided tinnitus and sudden sensorineural hearing loss (SSNHL).

Subjective benign paroxysmal positional vertigo.

Objective: To study the demographic, clinical, pathogenetic, and nystagmographic features and treatment outcomes of subjective benign paroxysmal positional vertigo (BPPV).

Study Design: Prospective clinical trial.

Setting: Tertiary referral center.

Treatment of the horizontal semicircular canal canalithiasis: pros and cons of the repositioning maneuvers in a clinical study and critical review of the literature.

Objective: Several repositioning maneuvers have been proposed for the treatment of benign paroxysmal positional vertigo (BPPV) due to canalithiasis of the horizontal semicircular canal (HSC). However, comparisons between these canalith repositioning procedures as well as a generally accepted algorithm for the management of HSC canalithiasis are currently lacking. The aim of this study was to compare the efficacy of 3 different treatment proposals and review the relevant literature.

Inner ear disease and benign paroxysmal positional vertigo: a critical review of incidence, clinical characteristics, and management.

Background. This study is a review of the incidence, clinical characteristics, and management of secondary BPPV. The different subtypes of secondary BPPV are compared to each other, as well as idiopathic BPPV.

Detection of deafness-causing mutations in the Greek mitochondrial genome.

Mitochondrion harbors its own DNA, known as mtDNA, encoding certain essential components of the mitochondrial respiratory chain and protein synthesis apparatus. mtDNA mutations have an impact on cellular ATP production and many of them are undoubtedly a factor that contributes to sensorineural deafness, including both syndromic and non-syndromic forms. Hot spot regions for deafness mutations are the MTRNR1 gene, encoding the 12S rRNA, the MTTS1 gene, encoding the tRNA for Ser^{(UCN)}, and the MTTL1 gene, encoding the tRNA for Leu^{(UUR)}.

Universal newborn hearing screening, a revolutionary diagnosis of deafness: real benefits and limitations.

The finding that early detection of permanent congenital childhood hearing loss produces worthwhile benefit in terms of improved speech and language provides the rationale for the universal screening of newborns. The aim of the present study is to collect the current evidence with regard to the efficacy, the results and outcomes of universal hearing screening programs. An extensive search of the literature was performed in Medline and other available database sources.

Vestibular evoked myogenic potentials in patients with BPPV.

Background: The probable cause of Benign Paroxysmal Positional Vertigo (BPPV) is a degeneration of the oto lithic organs (utricle and saccule). The aim of the study is to find possible alterations in Vestibular Evoked Myogenic Potentials (VEMP) recordings in BPPV patients, because the saccule is part of the VEMP pathway.

Material/methods: 27 BPPV patients (24 unilateral and 3 bilateral) aged 20 to 70 years and 30 healthy age matched controls.

Homoplasmy of the G7444A mtDNA and heterozygosity of the GJB2 c.35delG mutations in a family with hearing loss.

Objective: Mitochondrial mutations have been shown to be responsible for syndromic as well as non-syndromic hearing loss. The G7444A mitochondrial DNA mutation affects COI/the precursor of tRNA(Ser(UCN)), encoding the first subunit of cytochrome oxidase. Here we report on the first Greek family with the G7444A mitochondrial DNA mutation.

Prognosis of patients with idiopathic sudden hearing loss: role of vestibular assessment.

Objective: To evaluate the correlation between caloric and vestibular evoked myogenic potential test results, initial audiogram data, and early hearing recovery, in patients with idiopathic sudden hearing loss.

Materials And Methods: One hundred and four patients with unilateral idiopathic sudden hearing loss underwent complete neurotological evaluation. Results for vestibular evoked myogenic potential and caloric testing were compared with patients' initial and final audiograms.

Aural symptoms in patients with temporomandibular joint disorders: multiple frequency tympanometry provides objective evidence of changes in middle ear impedance.

Objective: The association of temporomandibular joint (TMJ) disorders with aural symptoms, such as tinnitus, otic fullness, and subjective decrease of hearing acuity, is a well-established clinical observation. Although several hypotheses have been made about the otic-conductive origin of these complaints, conventional 226-Hz tympanometry has failed to demonstrate any middle ear abnormalities. The aim of this study was to evaluate patients with TMJ disorders with multiple frequency tympanometry (MFT).

Design and construction of a novel tribometer with online topography and wear measurement.

We present a novel experimental platform that links topographical and material changes with the friction and wear behavior of oil-lubricated metal surfaces. This concept combines state-of-the-art methods for the analysis of the surface topography on the micro- and nanoscale with the online measurement of wear. At the same time, it allows for frictional and lateral force detection.

Screening protocols for the prevention of occupational noise-induced hearing loss: the role of conventional and extended high frequency audiometry may vary according to the years of employment.

Background: Although occupational noise-induced hearing loss (NIHL) has become a major problem in industrialized societies, there is a notable lack of effective screening protocols to ensure its early diagnosis. The aim of this study was to detect a potential role of extended high frequency (EHF) audiometry in industrial hearing screening protocols.

Material/methods: The population consisted of 151 persons, working for 8 hours daily in a noisy environment (90-110 dBA).

Canalithiasis of the anterior semicircular canal (ASC): treatment options based on the possible underlying pathogenetic mechanisms.

Benign paroxysmal positional vertigo (BPPV) of the anterior semicircular canal (ASC) is an uncommon disorder currently diagnosed with the Dix-Hallpike (D-H) examination. According to the literature, nystagmus and vertigo may be more pronounced when the affected ear is either up or down. In some patients, both right and left D-H tests can trigger nystagmus with the same direction.

Are GJB2 mutations an aggravating factor in the phenotypic expression of mitochondrial non-syndromic deafness?

Hearing impairment is a frequent condition, and genes have an important role in its etiology. The majority of hearing loss occurs in non-syndromic form, with deafness being the only clinically recognizable feature. More than 60 nuclear genes or loci have been shown to be involved in non-syndromic hearing loss, but mutations in mitochondrial DNA also cause hearing impairment.

Tinnitus Retraining Therapy (TRT): outcomes after one-year treatment.

The aim of the study is to present our results regarding the efficacy of TRT for tinnitus relief in patients with clinically significant tinnitus compared to a group treated with vasoactive agents. In a nonrandomized prospective study, 63 patients with disabling tinnitus were recruited. Greek translation of the Tinnitus Handicap Inventory (THI) and visual analogue scale (VAS) for annoyance caused by tinnitus when conducting four major activities of everyday life (work, sleep, relaxation and concentration) were examined in a 12-month period.

The diagnostic value of earlier and later components of Vestibular Evoked Myogenic Potentials (VEMP) in multiple sclerosis.

Aim Of The Study: To evaluate the ability of VEMP to disclose spatial dissemination of Multiple Sclerosis.

Materials And Methods: Forty-six MS patients with auditory and/or vestibular symptoms were studied. Patients were divided in two groups.