Cochlear implantation in osteogenesis imperfecta in India: a case report

<p class="abstract">A 25 years old male patient with osteogenesis imperfecta presented with bilateral profound hearing loss, not benefitted with hearing aid. Cochlear implantation of 12 channel intracochlear implant was done successfully, intracochlear insertion of the 12 electrodes resulted in hearing improvement of 80 dB at frequency 250 Hz to 4 KHz. The patient complained of facial twitching on first visit after switching on speech processer device, reducing the current level at the electrode 6 abolished the non-acoustic nerve excitation with preservation of acoustic performances. Osteogenesis imperfecta patient may involve a risk for non-acoustic nerve activation in cochlear implant patients possibly resulting from a decrease impedance to current spread, it happens because of abnormal bone tissue. Non acoustic nerve activation can be overcome by modification in mapping.</p>

Retina and optic nerve complications and hearing injury caused by Sclerotherapy of Facial Vascular Malformation

This report describes a complication of symptoms consistent with transiency visual acuity damage and hearing injury following sclerotherapy with a polidocanol injection to a facial vascular malformation. After the direct injection of 5cc polidocanol-room air emulsion into the subcutaneous malformation, a 3-year-old boy developed bilateral eyelid swelling the next day, and on 7 days later at referral, visual acuity in the left eye was light perception. Fundoscopy revealed retinal hemorrhage; fluorescein angiography (FA) disclosed hyperreflective leakage on the optic disk 15 days later, and OCT showed nerve fiber edema between the disk and macular. The orbital magnetic resonance imaging (MRI) demonstrated the normal extraocular muscles. In a month later, bilateral eyelid swelling resolved but the visual acuity remained 20/500, and 20/20 in two months later, but the hearing injury remained. It needs much more special attention in sclerotherapy for facial malformation because the sclerosants may cause severe toxicity or inflammation in retina and optic nerve, resulting in transiency visual acuity damage and acoustic nerve injury. The related examination including ophthalmic investigation after the sclerotherapy is necessary.

HCG11 up-regulation induced by ELK4 suppressed proliferation in vestibular schwannoma by targeting miR-620/ELK4

Background Vestibular schwannoma (VS) is a kind of benign tumor deriving from the acoustic nerve sheath. Substantial long non-coding RNAs (lncRNAs) were illustrated to have crucial roles in multiple cancers. However, few lncRNAs were elucidated in VS. Methods HCG11, miR-620 and ELK4 expression were tested by RT-qPCR. Gain-of-function experiments were conducted to confirm the effect of HCG11 on VS. Results HCG11 possessed a low expression in VS cell lines. Overexpression of HCG11 repressed cell proliferation but accelerated apoptosis of VS cells. Moreover, we identified ELK4 stimulated the transcription of HCG11 and their affinity was verified by ChIP assays. MiR-620 was chosen to be a target of HCG11 and it was tested to have a high expression in VS cell lines. Moreover, depletion of miR-620 could inhibit cell proliferative ability while fostering apoptosis rate of VS cells. ELK4 was low expressed in VS cell lines and knockdown of ELK4 could rescue the effects made by HCG11 overexpression on progression of VS. Conclusions HCG11 could inhibit the growth of VS by targeting miR-620/ELK4 in VS cells. HCG11 was a novel therapeutic target for VS treatment.

Mosaic PTEN alteration in the neural crest during embryogenesis results in multiple nervous system hamartomas

The contribution of mosaic alterations to tumors of the nervous system and to non-malignant neurological diseases has been unmasked thanks to the development of Next Generation Sequencing (NGS) technologies. We report here the case of a young patient without any remarkable familial medical history who was first referred at 7 years of age, for an autism spectrum disorder (ASD) of Asperger type, not associated with macrocephaly. The patient subsequently presented at 10 years of age with multiple nodular lesions located within the trigeminal, facial and acoustic nerve ganglia and at the L3 level. Histological examination of this latter lesion revealed a glioneuronal hamartoma, exhibiting heterogeneous PTEN immunoreactivity, astrocyte and endothelial cell nuclei expressing PTEN, but not ganglion cells. NGS performed on the hamartoma allowed the detection of a PTEN pathogenic variant in 30% of the reads. The presence of this variant in the DNA extracted from blood and buccal swabs in 3.5 and 11% of the NGS reads, respectively, confirmed the mosaic state of the PTEN variant. The anatomical distribution of the lesions suggests that the mutational event affecting PTEN occurred in neural crest progenitors, thus explaining the absence of macrocephaly. This report shows that mosaic alteration of PTEN may result in multiple central and peripheral nervous system hamartomas and that the presence of such alteration should be considered in patients with multiple nervous system masses, even in the absence of cardinal features of PTEN hamartoma tumor syndrome, especially macrocephaly.

Pathophysiology of noise-induced cardiovascular diseases

According to the noise reaction model introduced by Babisch, two principal pathways have been theorized as being responsible for the adverse health effects of noise: a direct and an indirect pathway. The direct pathway is activated by an instantaneous interaction of the acoustic nerve with structures of the central nervous system. The indirect pathway in turn represents the cognitive perception of the sound and its subsequent cortical activation, and is related to emotional responses.