The present study introduces an overview of gentamicin-clay mineral systems for applications in biomedicine and then focuses on the development of a series of gentamicin/clay hybrid materials to be used as the bioactive phase of hydroxypropylmethylcellulose (HPMC) to produce bionanocomposite membranes possessing antimicrobial activity of interest in wound-dressing applications. Gentamicin (Gt) was adsorbed from aqueous solutions into a montmorillonite (Cloisite®-Na+) to produce intercalation compounds with tunable content of the antibiotic. The hybrids were characterized by CHN chemical analysis, energy-dispersive X-ray analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, and thermogravimetric analysis, confirming the intercalation of Gt by an ion-exchange mechanism. The release of Gt from the hybrids was tested in water and in buffer solution to check their stability. Hybrids with various amounts of Gt were incorporated into a HPMC matrix at various loadings and processed as films by the casting method. The resulting Gt-clay/HPMC bionanocomposites were characterized by means of field-emission scanning electron microscopy, and were also evaluated for their water-adsorption and mechanical properties to confirm their suitability for wound-dressing applications. The antimicrobial activity of the bionanocomposite films was tested in vitro toward various microorganisms (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus faecium, Acinetobacter baumannii, and Klebsiella pneumonia), showing a complete bacterial reduction even in films with small Gt contents.

Infectious diseases impair Se metabolism, and low Se status is associated with mortality risk in adults with critical disease. The Se status of neonates is poorly characterised, and a potential impact of connatal infection is unknown. We hypothesised that an infection negatively affects the Se status of neonates. We conducted an observational case–control study at three intensive care units at the Charité-Universitätsmedizin Berlin, Germany. Plasma samples were collected from forty-four neonates. On the basis of clinical signs for bacterial infection and concentrations of IL-6 or C-reactive protein, neonates were classified into control (n 23) and infected (n 21) groups. Plasma Se and selenoprotein P (SePP) concentrations were determined by X-ray fluorescence and ELISA, respectively, at day of birth (day 1) and 48 h later (day 3). Se and SePP showed a positive correlation in both groups of neonates. Se concentrations indicative of Se deficit in adults (<20 µg/l) were observed in four infected neonates and one control subject, and three infected neonates had very low SePP concentrations (<0·5 mg/l). The univariate analysis revealed a significant difference in Se and SePP concentrations between the groups. Both parameters correlated inversely to IL-6 in neonates with severe inflammation (IL-6>500 ng/l). During antibiotic therapy, SePP increased significantly from day 1 (1·03 (sd 0·10) mg/l) to day 3 (1·34 (sd 0·10) mg/l), indicative of improved hepatic Se metabolism. We conclude that both Se and SePP are suitable biomarkers for assessing Se status in neonates and for identifying subjects at risk of deficiency.

Objective: The aim of this study was to assess the experiences and outcomes of patients receiving intratympanic gentamicin treatment for Ménière's disease in Norfolk, UK.

Design: This study was based on a retrospective questionnaire survey and a review of patients' medical records.

Setting: Two district hospitals.

Participants: All 29 patients treated between 1999 and 2001, with a minimum follow up of two years post-treatment, were included in the study. Twenty-three patients completed the questionnaires (79 per cent response rate).

Main outcome measures: Glasgow benefit inventory (GBI) and vertigo symptom scale (VSS) scores, plus change in hearing thresholds.

Results: The mean GBI total score was +36, indicating substantial improvement in patients' overall quality of life following gentamicin treatment. The VSS scores demonstrated low levels of vertigo or unsteadiness in treated patients. Three patients suffered deterioration in their hearing thresholds following a single injection of gentamicin. However, 96 per cent of responders stated that they would be willing to have such treatment again, if necessary.

Conclusion: Intratympanic gentamicin treatment ought to be offered to Ménière's patients suffering from disabling vertigo, with the proviso that they be made aware of the possibility of hearing deterioration.

Objectives: To evaluate patients' quality of life after receiving intratympanic gentamicin as treatment for Ménière's disease.

Design: Retrospective study using the Glasgow benefit inventory scale (GBI) questionnaire.

Participants: Patients diagnosed with Ménière's disease, according to the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) diagnostic criteria (refractory to medical management), who were treated with intratympanic gentamicin injection.

Materials and methods: This retrospective study included all patients diagnosed with Ménière's disease (according to AAO-HNS criteria; refractory to medical management) undergoing gentamicin labyrinthectomy in our unit over the preceding three years. Other causes of hearing loss were ruled out as all patients underwent magnetic resonance imaging, electronystagmography and sway magnetometry. Patients underwent gentamicin infiltration at a concentration of 2 ml of 30 mg/ml and were reviewed six weeks later and received a repeat injection if no benefit was evident. Six months after their last follow up, they were sent a GBI questionnaire. Twenty-one questionnaires were posted, and the response rate was 81 per cent.

Results: As per the responses received, the total benefit of intratympanic gentamicin injection was found to be +30.3. The three components of GBI were analysed separately; it was found that general benefit was greatest (+33.3), followed by physical benefit (+28.1) and social benefit (+21.6).

Conclusion: This study suggests that gentamicin definitely improves quality of life in patients with Ménière's disease and should be the first line of treatment if medical management fails.

The pathogenesis of Ménière's disease is associated with a disorder of ionic homeostasis, with the pathologic correlate being endolymphatic hydrops. Despite uncertainty as to its particular mode of action, it is accepted wisdom that intra-tympanic gentamicin has a definite therapeutic role in the control of symptoms in patients who fail to respond to medical therapy. This study reports an evaluation of the efficacy of intra-tympanic gentamicin in the treatment of Ménière's disease and also presents a simple, reliable, safe method of administering gentamicin for this purpose.

A retrospective review of 56 patients undergoing intra-tympanic gentamicin treatment for Ménière's disease was conducted. Response to treatment was analysed using a patient survey and examination of pure-tone averages. An overall significant improvement in vertigo symptoms of 81.3 per cent was found. There was a 21.4 per cent rate of significant hearing loss, defined as greater than 10 dB, with an average loss in this group of 18.5 dB. A single dose of gentamicin applied directly to the round window resulted in a high rate of control of vertigo, with acceptably low rates of hearing loss.

Objectives: Transtympanic pressure has been shown to influence endolymphatic hydrops. As endolymphatic hydrops plays a key role in Ménière’s disease, a few studies, undertaken by the inventors, manufacturers and associates of the Meniett device,have demonstrated positive short-term effects of transtympanic pressure treatment via the Meniett device in medically intractable Ménière’s disease. The aim of our study was to independently investigate the long-term efficacy and safety of transtympanic pressure treatment in the management of recalcitrant vertigo in Ménière’s disease.

Design: Cross-sectional case study.

Setting: Tertiary referral centre.

Participants: Eighteen patients with Ménière’s disease, suffering from medically intractable symptoms. All patients in the study had Ménière’s disease according to the criteria of the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology, Head & Neck Surgery.

Main outcome measurements: Outcome and severity of symptoms were assessed, using the six-point functional scale and the vertigo visual analogue scale (VAS), as recommended by the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology, Head & Neck Surgery. Changes of pure tone average thresholds and vestibular calorics before and during treatment with the Meniett device were recorded. The mean follow-up time was 18 months.

Results: Twelve out of 18 patients showed significant improvement in the functional score and in the VAS. Five patients displayed an audiometric improvement, out of which three patients showed a pertaining significant hearing gain of more than 10 dB; the remainder had stable hearing levels. Of six patients without any improvement, four had previous invasive surgery for theirMénière’s disease and two had previous vestibular ablation with gentamicin.No changes in vestibular function were noted. There were no complications duringthe treatment with the Meniett device.

Conclusion: According to this independent study, the Meniett device seems to be a minimally invasive, non-destructive treatment tool, which can reduce vertigo and associated functional handicap in Ménière’s disease. These effects are maintained up to 18 months after treatment so far. Previous surgical or chemical vestibular ablation procedures may adversely influence the effect of the Meniett device.

There has been a steady increase in the number of cases of methicillin-resistant Staphylococcus aureus (MRSA) otorrhoea; this is a growing concern. The purpose of this study was to evaluate the efficacy of topical vancomycin treatment in patients with MRSA otorrhoea. Fifty-five patients with MRSA otorrhoea were prospectively enrolled into the study. Thirty-five patients were treated with vancomycin eardrops as outpatients. The concentration of the locally prepared vancomycin solution was 25 mg/ml. The dose of vancomycin was two drops three times daily for 10 days. As a control group, 20 patients were treated with gentamicin 0.3% solution. Data were analysed by the Mann-Whitney U test to compare the efficacy of vancomycin eardrops and gentamicin eardrops. In the vancomycin group, the otorrhoea was significantly reduced in 33 ears (94%); in the gentamicin group, in four ears (20 per cent); this reduction was statistically significant (P < 0.03). The use of topical vancomycin treatment was effective for patients with MRSA otorrhoea refractory to conventional antibiotic treatment.

Scanning electron microscopy (SEM) was used to study the endometrium of nine 1-year-old thoroughbred mares after twice intrauterine infusions of gentamicin, on 2 consecutive days. Five mares were infused on 2 consecutive days with 40 ml gentamicin (50 mg/ml) mixed with 80 ml of normal saline. Four mares served as controls and were infused with 120 ml of saline on 2 consecutive days. Endometrial biopsies were obtained from all mares 3 days after the second intrauterine infusion. Each biopsy was processed for SEM by standard methods. The endometrial epithelium of the gentamicin-infused mares had more cellular perforations than the saline-infused mares. The gentamicin-infused mares had less and shorter microvilli. The ciliated cells were fewer and some ciliated cells had disrupted and some had drooping cilia. The endometrial epithelium of the gentamicin-infused mares had a considerable number of endometrial cells that lost their luminal surfaces and some that lost their microvilli, compared to the saline-infused mares. We suggest that the information gathered in this pilot study should be used as basis for further investigation, on a larger scale basis, of the effects of repeated intrauterine infusion of gentamicin on the endometrial mucosa of mares.