José Ángel González-García

20 kHz sonoelectrochemical degradation of perchloroethylene in sodium sulfate aqueous media: influence of the operational variables in batch mode.

A preliminary study of the 20 kHz sonoelectrochemical degradation of perchloroethylene in aqueous sodium sulfate has been carried out using controlled current density degradation sonoelectrolyses in batch mode. An important improvement in the viability of the sonochemical process is achieved when the electrochemistry is implemented, but the improvement of the electrochemical treatment is lower when the 20 kHz ultrasound field is simultaneously used. A fractional conversion of 100% and degradation efficiency around 55% are obtained independently of the ultrasound power used. The current efficiency is also enhanced compared to the electrochemical treatment and a higher speciation is also detected; the main volatile compounds produced in the electrochemical and sonochemical treatment, trichloroethylene and dichloroethylene, are not only totally degraded, but also at shorter times than in the sonochemical or electrochemical treatments.

Alternatives to systemic steroid therapy for refractory immune-mediated inner ear disease: a physiopathologic approach

Immune-mediated inner ear disease (IMIED) is one of the few forms of reversible sensorineural hearing loss. Corticosteroids-responsive patients are usually associated with hearing improvement. Due to the long clinical course of IMIED that frequently present recurrences (hearing loss and vertigo), alternatives to corticosteroids such as methotrexate and recently TNF-α blockers have been proposed. Likewise new procedures for delivering corticosteroids to the inner ear have been developed. The aim of this article is to assess the efficacy of methotrexate and transtympanic 6-methylprednisolone in refractory IMIED. From a database of 200 patients affected by IMIED, 16 selected patients with refractory disease were included in the present study. Five patients were treated with methotrexate and 11 by means of transtympanic injection of 6-methylprednisolone. All patients treated with methotrexate had an improvement in their vestibular symptoms. However, hearing loss did not improve. Most patients treated with local 6-methylprednisolone (68.75%) showed an improvement in hearing loss and vestibular symptoms. Methotrexate has been shown to be ineffective in maintaining long-term remissions of hearing relapses although patients presented an improvement in vestibular symptoms. However, transtympanic 6-methylprednisolone has been shown to be a safe, easy and useful therapy in refractory IMIED and it may actually become the first-line treatment for these patients based on the existence of glucocorticoid receptors and the possible targets of immune-mediated damage within the inner ear.

Kinetics of Electrocrystallization of PbO2 on Glassy Carbon Electrodes Partial Inhibition of the Progressive Three‐Dimensional Nucleation and Growth

Conselleria de Cultura, Educacion y Ciencia de la Generalidad Valenciana (project GV-2231-94) and D.G.I.C.Y.T. (project QUI97-1086).

Ginkgo biloba extract (EGb761) protects against aging-related caspase-mediated apoptosis in rat cochlea

Abstract Conclusions: EGb761 treatment has a significant benefit with an early and preventive effect, reversing the deleterious effect of aging in the integrity of the rat cochlea, even in the late stage of the rat lifespan. Objectives: We previously reported a significant relationship between aging and apoptosis in the rat cochlea. This study was designed to investigate the effects of Ginkgo biloba leaf extract (EGb761) on age-associated cochlear caspase activation. Methods: Sprague-Dawley rats (n = 80) divided into two groups according to their age (4 months old, younger, YR, and 12 months old, aged-mature, AM) were treated with 100 mg/kg/day body weight of EGb761 extract dissolved in tap water for two periods: 4 and 12 months. Then cochleae were harvested to measure caspase activities, ATP levels, total superoxide dismutase (SOD) activity, and caspase-3 gene expression. Auditory steady-state responses (ASSR) threshold shifts were also measured before sacrifice of the rats. Results: EGb761 treatment prevents significantly aging-related caspase-induced activities within the cochleae in YR and AM rats. In the short EGb761 treatment, YR rats showed lower levels of caspase-3/7 than AM rats. In contrast, longer treatment did not show significant differences between YR and AM rats. Reduced caspase-3/7 activity in presence of EGb761 correlates with significant improvements of ASSR threshold shifts.

Enlarged vestibular aqueduct: looking for genotypic–phenotypic correlations

The aim of this work is to provide a guide for clinical and genetic diagnosis and classification of the enlarged vestibular aqueduct syndrome based on a review of the literature and computerized databases with the words large and enlarged vestibular aqueduct. No more than 40 articles described association between the EVA phenotype and a known genetic alteration. Pendred’s syndrome, distal renal tubular acidosis, waardenburg’s syndrome, X-linked congenital mixed deafness, branchio-oto-renal syndrome, and oto-facio-cervical syndrome can express their genotypic alteration as enlarged vestibular aqueduct syndrome. We also found articles reporting familiar cases of enlarged vestibular aqueduct with no identified mutations in studied genes.

Endogenous protection against oxidative stress caused by cisplatin: role of superoxide dismutase

Abstract Conclusion: The administration of cisplatin induces the activation of superoxide dismutase (SOD) as a response to oxidative stress in the cochleae of Sprague-Dawley rats and this activation is proportional to the activation of the intrinsic pathway of apoptosis. Objectives: To determine the role of the antioxidant endogenous mechanism in the preservation of cochlear integrity and function in an experimental model of cisplatin ototoxicity. Methods: Sixteen Sprague-Dawley rats were studied at 7 days after intraperitoneal injection of CDDP (n = 8) or 10 ml/kg NaCl 0.9% w/v in the control group (n = 8) by means of auditory steady-state responses. These findings were compared with the expression of SOD and caspase-3/7 and caspase-9 activities. Results: Groups receiving cisplatin showed increased auditory thresholds after injection of cisplatin and control groups maintained normal hearing. Measurements of caspase-3/7 and caspase-9 showed a significant increase in cisplatin-treated rats. A significantly increased activity of total SOD in whole cochlear extracts was observed in animals from the CDDP groups vs control animals. Likewise, differences between CDDP groups were also statistically significant.

Electrochemical Synthesis of L-Histidinol Using Solvated Electrons

The feasibility of the preparation of L-histidinol (I) by reduction of L-histidine methyl ester (II) using an electrogenerated solvated electrons solution has been studied in a laboratory scale reactor. The solvated electrons solution was obtained by electrolysis of a solution of LiCI in EtNH 2 that permits an easier handling than NH 3 or MeNH 3 . All components of the electrochemical setup have been optimized for the reaction conditions used. The influence of some reaction variables on the yield of (I) has been studied. Thus, increasing current intensity and temperature enhances the yield of L-histidinol. Nevertheless, the volatility of ethylamine limits the increase of the intensity current and the temperature. A fractionated feeding procedure of (II) was shown to be desirable. The work-up and isolation procedure of (I) has also been described. It includes an electrodialysis process that makes easier the isolation of (I), as well as the recovered LiCl could be recycled as supporting electrolyte.

Incarceración total de prótesis fonatoria en la mucosa traqueoesofágica. Informe de una nueva complicación con el uso de prótesis fonatorias

We report the cases of three patients seen at the Otolaryngology Department after presenting a laryngeal carcinoma that required total laryngectomy, followed by trachaeo-oesophageal puncture and Provox voice prosthesis positioning. In all cases the growth of granulomatous tissue totally incarcerated the prosthesis in the trachaeo-oesophageal mucosa. In two of the cases the prosthesis could be extracted by oesophagoscopy and a new prosthesis was positioned in the same surgery. In the other case an external approach was performed using a peristomal wound to extract the prosthesis. In this case a new trachaeo-oesophageal puncture was performed 3 months after the extraction.

[Total voice prosthesis incarceration in the trachaeo-oesophageal mucosa. Report of a new complication when using phonatory prostheses].

Abstract We report the cases of three patients seen at the Otolaryngology Department after presenting a laryngeal carcinoma that required total laryngectomy, followed by tracheo-oesophageal puncture and Provox voice prosthesis positioning. In all cases, the growth of granulomatous tissue totally incarcerated the prosthesis in the tracheo-oesophageal mucosa. In two of the cases, the prosthesis could be extracted by oesophagoscopy and a new prosthesis positioned in the same surgery. In the third case, an external approach was performed using a peristomal incision to extract the prosthesis. A new tracheo-oesophageal puncture was then performed 3 months after the extraction.

Does the Serological Study for Viral Infection in Autoimmune Inner Ear Disease Make Sense

Viral infections of the labyrinth have been considered a major source of auditory and vestibular system pathology. However, the involvement of virus in the development of immune reactions responsible for immunomediated inner ear disease has not been studied enough. Following viral infection, an effector immune response, humoral (B cell) and/or cytotoxic (T cell) is directed against a virus and it might cross-react with self-protein or autoantigen, evoking an autoimmune response. Since clinically it can be very difficult to establish a viral etiology for such disorders, serologic studies can be used to confirm the suspected diagnosis. Patients affected by immunomediated inner ear disease that had presented an upper respiratory tract infection underwent an immunologic workup study including microbiological study. After the application of this diagnostic protocol, only one patient, that was subsequently diagnosed with Cogan’s syndrome, showed a positive serological test for viral infection. On the basis of the low efficacy of serological testing and due to the lack of evidence, we do not recommend to carry out serologic studies for viral infection.