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As L-type voltage-gated calcium channels (VGCCs) control Ca(2+) influx and depolarisation of cardiac and vascular smooth muscle, they represent a specific therapeutic target for calcium channel blockers (CCBs), which are approved and widely used to treat hypertension, myocardial ischaemia and arrhythmias. L-type currents also play a role in calcium entry in the sensory cells of the inner ear. In hair cells of both cochlea and labyrinth, calcium cytoplasmic influx is the first physiological process that activates complex intracellular enzymatic reactions resulting in neurotransmitter release. Excessive calcium ion entry into sensory cells, as a consequence of L-VGCCs malfunction is responsible for over-activation of phospholipase A2 and C, protein kinase II and C, nitric oxide synthase and both endonucleases and depolymerases, which can cause membrane damage and cellular death if the cytoplasmic buffering capacity is overcome. Nimodipine, a highly lipophilic 1-4 dihydropyridine that easily crosses the brain-blood barrier, is generally used to reduce the severity of neurological deficits resulting from vasospasm in patients with subarachnoid haemorrhage. Moreover, due to its selective blocking activity on L-channel calcium currents, nimodipine is also suggested to be an effective countermeasure for cochlear and vestibular dysfunctions known as channelopathies. Indeed, experimental data in amphibians and mammalians indicate that nimodipine has a stronger efficacy than other CCBs (aminopyridine, nifedipine) on voltage-dependent whole-cell currents within hair cells at rest and it is the only agent that is also effective during their mechanically induced depolarisation. In humans, the efficacy of nimodipine is documented in the medical management of peripheral vestibular vertigo, sensorineural hearing loss and tinnitus, even in a pathology as complex as Ménière's disease. Nimodipine is also considered useful in the prophylaxis of damage to the facial and cochlear nerves caused by ablative surgery of cerebellopontine tumours; it has been recently hypothesised to accelerate functional recovery of recurrent nerve lesions during thyroid cancer surgery. Further trials with adequate study design are needed to test the efficacy of nimodipine in the treatment of vertigo due to cerebrovascular disease and vestibular migraine.I canali del calcio di tipo L sono indispensabili alla normale contrattilità del miocardio e della muscolatura liscia del sistema vascolare. In quanto tali, essi rappresentano uno specifico bersaglio terapeutico di una vasta famiglia di farmaci ad attività calcio-antagonista, che sono ampiamente usati per trattare l'ipertensione, l'ischemia miocardica e le aritmie. Tuttavia, i canali del calcio di tipo L svolgono un ruolo determinante anche nel normale funzionamento delle cellule sensoriali nell'orecchio interno. Nelle cellule cigliate, infatti, sia della coclea che del labirinto, l'ingresso del calcio all'interno del citoplasma è il primo processo fisiologico che attiva un complesso di meccanismi intracellulari, ovvero una sequenza di attivazioni enzimatiche, il cui risultato finale è il rilascio dei neurotrasmettitori a livello delle sinapsi. Al contrario, una concentrazione eccessiva di ioni calcio nelle stesse cellule sensoriali, ad esempio come conseguenza di un malfunzionamento dei canali del calcio di tipo L, è responsabile dell'attivazione delle fosfolipasi di tipo A2 e C, delle protein-chinasi II e C, dell'ossido nitrico sintetasi che possono causare un danno alla membrana plasmatica e la stessa morte cellulare qualora i limiti funzionali dei sistemi tampone del citoplasma vengano superati. La nimodipina, un agente altamente lipofilo, appartenente alla famiglia delle 1-4 diidropiridinine, che attraversa facilmente la barriera emato-encefalica, è generalmente utilizzata per ridurre la gravità dei deficit neurologici derivanti da vasospasmo nei pazienti con emorragia subaracnoidea. Inoltre, a causa della sua azione calcio-antagonista che si esplica selettivamente nei confronti dei canali del calcio di tipo L, viene suggerita come trattamento farmacologico efficace principalmente per quelle disfunzioni cocleari e vestibolari che vengono considerate delle "canalopatie". In effetti, i dati sperimentali ottenuti negli anfibi e in alcune specie di mammiferi indicano che nimodipina ha maggiore efficacia di altri calcioantagonisti (aminopiridina e nifedipina) nel bloccare le correnti di ioni calcio in ingresso nelle cellule ciliate e che è l'unico calcio-antagonista a mantenere tale efficacia anche durante la loro depolarizzazione indotta da stimolo meccanico. Negli esseri umani l'efficacia terapeutica della nimodipina è stata documentata nel trattamento della vertigine labirintica, dell'ipoacusia neurosensoriale e dell'acufene anche se riferibili ad una patologia complessa e non ancora del tutto chiarita come la malattia di Ménière. La nimodipina è inoltre considerata un valido approccio farmacologico nella profilassi dei danni neurali ai nervi facciali e cocleari causati dalla chirurgia ablativa dei tumori dell'angolo ponto-cerebellare ed è stata recentemente indicata per accelerare il recupero funzionale delle lesioni del nervo ricorrente conseguenti alla chirurgia del cancro alla tiroide. Per verificare, infine, l'efficacia della nimodipina nel trattamento delle vertigini di origine centrale, perlopiù associate ai disordini cerebrovascolari, e nel trattamento della vertigine emicranica, sono necessari ulteriori studi che confermino con maggiore rigore scientifico tali prospettive, peraltro già ampiamente riportate nella letteratura scientifica.

Background: Meniere's disease (MD) has been recently linked to gluten assumption. Approximately 75% of MD patients show positive skin test to food and about 50% of the positive responses are specific to the gliadin acid extract fraction. Aim of this study was to investigate the humoral immune responses to wheat antigens and related autoantigens in MD patients. Methods. We assessed the reactivity of sera from 28 patients with definite MD and 100 healthy controls against a repertoire of 51 antigens usually associated with immune reaction to gluten. Results. MD patients showed an increase of anti-wheat IgA, anti-cerebellar peptide IgA and anti-glutamic acid decarboxylase (GAD) 65 IgM compared to healthy controls. In particular, the increase of anti-wheat IgA and GAD 65 IgM has been confirmed in a subgroup of MD patients symptomatically responding to a gluten free diet (GFD). Conclusion. In MD patients, an increase of the antibody production against gluten biomarkers was observed; in particular, anti-wheat IgA seems to be associated to clinical response to GFD.

Currently, the most commonly used electrophysiological tests for cochlear implant evaluation are Averaged Electrical Voltages (AEV), Electrical Advisory Brainstem Responses (EABR) and Neural Response Telemetry (NRT). The present paper focuses on the study of acoustic auditory cortical responses, or slow vertex responses, which are not widely used due to the difficulty in recording, especially in young children. Aims of this study were validation of slow vertex responses and their possible applications in monitoring postimplant results, particularly restoration of hearing and auditory maturation. In practice, the use of tone-bursts, also through hearing aids or cochlear implants, as in slow vertex responses, allows many more frequencies to be investigated and louder intensities to be reached than with other tests based on a click as stimulus. Study design focused on latencies of N1 and P2 slow vertex response peaks in cochlear implants. The study population comprised 45 implant recipients (aged 2 to 70 years), divided into 5 different homogeneous groups according to chronological age, age at onset of deafness, and age at implantation. For each subject, slow vertex responses and free-field auditory responses (PTAS) were recorded for tone-bursts at 500 and 2000 Hz before cochlear implant surgery (using hearing aid amplification) and during scheduled sessions at 3rd and 12th month after implant activation. Results showed that N1 and P2 latencies decreased in all groups starting from 3rd through 12th month after activation. Subjects implanted before school age or at least before age 8 yrs showed the widest latency changes. All subjects showed a reduction in the gap between subjective thresholds (obtained with free field auditory responses) and objective thresholds (obtained with slow vertex responses), obtained in presurgery stage and after cochlear implant. In conclusion, a natural evolution of neurophysiological cortical activities of the auditory pathway, over time, was found especially in young children with prelingual deafness and implanted in preschool age. Cochlear implantation appears to provide hearing restoration, demonstrated by the sharp reduction of the gap between subjective free field auditory responses and slow vertex responses threshold obtained with hearing aids vs. cochlear implant.

EPD is the only preventive symptomatic immunotherapy available on the market and approved by competent bodies. Recent double-blind placebo controlled (DBPC) studies have demonstrated its efficacy in seasonal and perennial rhinitis. The aim of the study was to confirm the efficacy and safety of a single dose of immunotherapy administered six-eight weeks before the pollen season.Two simultaneous DBPC trials were carried out. The first consisted of 20 children with grass-pollen seasonal rhinitis (Bollate-Milano, Italy) and the second included 30 adult patients with Parietaria-pollen seasonal rhinitis (Genova, Italy). EPD was administered only to the active groups.A significant difference in favour of the active treatment groups was seen in oral antihistamine use (p0.05) during the peak pollen seasons. Throughout the pollen seasons, rhinoconjunctivitis scores for the two groups in both studies presented no significant difference, even if the values were lower in the active groups.The oral antihistamine reduction, observed in the active groups during the seasonal period, supports the efficacy of this treatment, although a significant improvement in the rhinoconjunctivitis symptoms was not observed, probably due to the use of oral antihistamine in the placebo groups. The overall profile of the EPD was good. It could be particularly suited for short term therapy to prevent seasonal symptoms in allergic patients.