Trophic support of mouse inner ear by neural stem cell transplantation

In the auditory system, efforts to reduce degeneration of spiral ganglion neurons have the immediate objective of improving clinical benefits of cochlear implants, which are small devices designed to stimulate spiral ganglion neurons electronically. Recent studies have indicated several neurotrophins can enhance survival of spiral ganglion neurons. However, the strategy for application of neurotrophins in inner ear is still a matter of debate. In this study, we examined the potential of cell therapy as a strategy for application of neurotrophins in the inner ear. Neural stem cells obtained from green fluorescent protein-transgenic mice were used as donor cells. Medium containing neural stem cells was injected into mouse inner ear. Histological analysis 4 weeks later revealed that transplant-derived cells survived in inner ear and that most transplant-derived cells in the cochlea had differentiated into glial cells. Moreover, expression of glial cell line-derived neurotrophic factor and brain-derived neurotrophic factor was observed in transplant-derived cells. These findings indicate that transplantation of neural stem cells can be a useful strategy for application of neurotrophins in inner ear.     

Arterial injury associated with tension-free vaginal tape procedure successfully treated by radiological embolization: a case report

A 75-year-old woman underwent a tension-free vaginal tape (TVT) procedure for urinary stress incontinence. The patient complained of lower abdominal pain, a feeling of lower abdominal distension and nausea three hours after the operation. In addition, systolic blood pressure decreased gradually to 80 mmHg. Enhanced computed tomography revealed a retropubic hematoma sized up to 16 cm X 12 cm X 11 cm and bleeding from a vessel running through the posterosuperior aspect of the pubic bone. Successively, arteriography was performed. The arteriogram also confirmed arterial injury, which was successfully treated by selective embolization using a gelatin sponge and pushable coils. Postoperative course was uneventful requiring neither blood transfusion nor surgical removal of the hematoma.     

Phonomicrosurgery for posterior glottic lesions using triangular laryngoscope

It is important to fully expose the posterior glottis to achieve adequate phonomicrosurgical resection of lesions in the posterior glottis. However, it is often difficult to obtain a sufficient view of the posterior glottis by ordinary direct laryngoscopy. We attempted to expose posterior glottic lesions using a triangular laryngoscope for adequate achievement of the surgery. We have performed phonomicrosurgery for 14 lesions in the posterior glottis including 5 early cancers, 1 dysplasia, 1 hemangioma, and 7 granulomatous lesions. Under general anesthesia, a triangular laryngoscope was set lateral to an intubation tube, shifting the tube anterolaterally toward the opposite side to expose the posterior glottis, which allowed simultaneous visualization of the vocal fold, the lateral wall, and a part of the posterior wall of the posterior glottis. The procedures were completed successfully in all cases. Modified placement of the triangular laryngoscope provided an excellent surgical view including the membranous portion of the vocal fold through the posterior glottis. All lesions have been well controlled during the follow up periods of 6–23 months. The triangular laryngoscope enables an alternative method for posterior glottic exposure. Modified placement of the laryngoscope can be easily performed and provides sufficient exposure of posterior glottic lesions for an adequate resection of those lesions.     

Regeneration of Aged Vocal Fold: First Human Case Treated With Fibroblast Growth Factor

Background/Objectives: Aged vocal folds are characterized by atrophy of the mucosa, which causes dysphonia and is difficult to treat. We have revealed a therapeutic potential of basic fibroblast growth factor (bFGF) for tissue regeneration of the aged vocal fold. We report here the first human case that has been treated with bFGF. Study Design: Institutional review board approved clinical human trial. Methods: A 63‐year‐old man with atrophied vocal folds was treated by local injection of 10 μg of bFGF into the left vocal fold under topical anesthesia. The effects of the injection were examined after 1 to 3 months by videostroboscopy, acoustic and aerodynamic measurements. Results: The atrophy of the vocal fold was improved at 1 week after the injection and glottic gap disappeared. Aerodynamic and acoustic parameters also showed remarkable improvement. These positive effects were maintained up to 3 months. Conclusion: The first case with aged vocal folds treated with bFGF administration is presented. The results are encouraging, suggesting therapeutic effects of bFGF for atrophied vocal folds in human.     

Afferent projection from reticular nuclei, inferior olive and cerebellum to lateral vestibular nucleus of the cat as demonstrated by horseradish peroxidase

Afferent connection to lateral vestibular nucleus (LVN) was examined using retrograde transport of horseradish peroxidase (HRP). When HRP was microiontophoretically applied to the immediate vicinity of the LVN neuron, which monosynaptically fired spike upon VIIIth cranial nerve stimulation, HRP-labelled cells were observed in the ipsilateral lateral reticular nucleus, bilateral gigantocellular nucleus, and contralateral dorsal cap and beta-nucleus of inferior olive in addition to various parts of cerebellum.     

Studies on intestinal absorption of sulpiride (2): transepithelial transport of sulpiride across the human intestinal cell line Caco-2

To determine the transport mechanism of sulpiride in an in vitro model of the human intestine, we investigated the transepithelial transport of this agent in Caco-2 cells. The transepithelial transport and intracellular accumulation of sulpiride were measured using Caco-2 cell monolayers cultured on a permeable membrane. The transepithelial transport of sulpiride in Caco-2 cells showed temperature dependence, and the transport was enhanced at weakly acidic pH on the apical side. These results demonstrate that the transepithelial transport of sulpiride is carrier mediated. To identify the drug transporter species that take part in the transepithelial transport of sulpiride, we examined the effects with the addition and preloading with specific substrates and inhibitors of various drug transporters. The results obtained from these examinations indicated that the apical-to-basolateral transport of sulpiride is mediated by the peptide transporter PEPT1, organic cation transporters OCTN1 and OCTN2 on the apical membrane, and the basolateral peptide transporter on the basolateral membrane. The basolateral-to-apical transport is mediated by the basolateral peptide transporter and organic cation transporter OCT1 on the basolateral membrane and by P-glycoprotein on the apical membrane. A decrease in the absorption of sulpiride may occur in coadministration protocols involving PEPT1-, OCTN1-, and OCTN2-transported drugs. Coadministration using the P-glycoprotein-transported drugs, in contrast, may enhance the absorption of sulpiride.     

Vocal cord fixation caused by an impacted fish bone in hypopharynx: report of a rare case

We report a rare case of vocal cord fixation caused by a fish bone in the hypopharynx. The patient was a 72-year-old woman. She presented with hoarseness that had appeared suddenly while eating baked fish. The diagnosis was suggested by a clinical history and confirmed by a computed tomography scan. The fish bone was removed via microlaryngoscopic operation under general anesthesia. The restoration of her vocal cord mobility required a few months. Vocal cord fixation is an extremely rare complication of a pharyngeal foreign body. In all of the few cases reported previously, the fixation was caused by mechanical obstruction of vocal cord movement or by recurrent nerve palsy secondary to inflammation. Our case is not typical of mechanical or inflammatory fixation. It is possible that the recurrent nerve was damaged directly by the fish bone.     

Drug delivery systems for the treatment of sensorineural hearing loss

Sensorineural hearing loss is one of the most common disabilities in our society. Experimentally, many candidates for therapeutic molecules have been discovered. However, the lack of safe and effective methods for drug delivery to the cochlea has been a considerable obstacle to clinical application. Local application of therapeutic molecules into the cochlea has been used in clinic and in animal experiments. Advances in pharmacological technology provide various drug delivery systems via biomaterials, which can be utilized for local drug delivery to the cochlea. Recent studies in the field of otology have demonstrated the potential of synthetic and natural biomaterials for local drug delivery to the cochlea. Although problems still remain to be resolved for clinical application, introduction into clinical practice of these controlled-release systems may be reasonable because of their certain advantages over previous methods.