OBJECTIVESTo review the identified deafness genes related to nonsyndromic hearing loss (NSHL) and summarize their expressions and functions in the cochlea and to introduce the current studies of molecular genetics on NSHL in China.

METHODSThe presented data are based on a review of the literature as well as the author' s experience with NSHL and communications with other researchers in China over the past 3 years.

RESULTSCurrently, 23 deafness genes related to NSHL have been cloned and identified. Some genes are associated with both NSHL and syndromic hearing loss (SHL), in both dominant and recessive deafness. Deafness genes have a highly specific expression pattern in the inner ear. Some functional categories are starting to emerge from a characterization of deafness genes. There are interacting genes in the genetic background that influence the extent of hearing impairment. The GJB3 gene, which is associated with high-frequency hearing impairment, was cloned in a Chinese laboratory. Mutations in some genes, such as GJB2 and mitochondrial 12S rRNA, have been screened in Chinese patients with NSHL. Mapping new deafness gene loci as well as identifying new genes and their functions is an active area of study in China.

CONCLUSIONSIt is challenging for us to continue identifying new deafness genes and analyze gene functions. By identifying genes responsible for monogenic hearing impairment, more insight may be gained into the molecular process of hearing and the pathology of hearing loss.

Chromosome Mapping ; Cloning, Molecular ; Connexin 26 ; Connexin 30 ; Connexins ; genetics ; Deafness ; genetics ; Humans ; Mutation

OBJECTIVE: To review the clinical manifestations and management of nasal sinus mucoceles with visual loss. METHOD: Medical records for 23 patients of paranasal sinus mucoceles with visual impairment were re viewed retrospectively during 8-year period (from 2002 to 2010). Ten mucoceles were found in the frontal or fronto-ethmoidal sinuses, 6 in the ethmoidal sinuses, 7 in the sphenoidal or spheno-ethmoidal sinuses. Because the majority of early chief complaints were problems related to vision, patients were often seen by ophthalmologists first. Poor vision was more common in patients with sphenoid or spheno-ethmoidal sinus mucoceles because of their proximity to the optic nerve. CT and MRI were important tools for diagnosing nasal sinus mucocele. The patients received endoscopic surgery to remove mucocele and to decompress the optic nerve. Steroid therapy was given postoperatively and routine examination with endoscopy were carried out during follow-up. RESULT: Postoperatively, the majority of symptoms, such as exophthalmos, epiphora, diplopia and headache, disappeared in all patients. However, vision recovery was observed only in some patients. Recovery of vision depended on the timing of surgery and severity of initial visual loss. Delay in treatment can seriously compromise recovery of vision impairment. Moreover, patients without light perception before surgery had poor visual recovery even if optic nerve decompressions were performed. CONCLUSION Endoscopic surgery is effective to nasal sinus mucocele with visual loss. Because visual recovery depends on prompt diagnosis and surgical intervention, a good understanding of the disease and prompt imaging studies are important.
Adolescent ; Adult ; Cysts ; complications ; diagnosis ; surgery ; Female ; Humans ; Male ; Middle Aged ; Paranasal Sinus Diseases ; complications ; diagnosis ; surgery ; Retrospective Studies ; Vision, Low ; etiology ; Young Adult

OBJECTIVE: To identify the genetic characteristics in patients with nonsydromic hearing loss (NSHL) in Hunan province, to determine the prevalence and spectrum of mutations in GJB2 gene, and to explore the pathogenic mechanism. METHODS: A total of 140 sporadic patients with NSHL were enrolled after clinical examination. Molecular studies were performed by amplifing the coding region of GJB2 gene, purifying the PCR products, and sequencing directly. Sequences were analysed by DNAStar software to determine GJB2 mutations in the patients. Special method was designed to confirm the unreported mutation. RESULTS: We detected GJB2 mutation in 56 out of the 140 patients (40%, 56/140). Both of the 2 alleles were mutated in 29 patients and 1 allele in the other 27 patients, and the rate of allele mutation was 30.4%(85/280). Ten variations were detected, including 7 mutations and 3 polymorphisms. The deaf-causing mutations were nonsense mutation c.139G>T; frameshift mutation c.235delC and c.176-191del16; and missense mutation c.109G>A, c.344T>G, c.550C>T and c.571T>C. The unreported missense mutation was c.344T>G. The c.235delC mutation was the most prevalent mutation found in the 27 patients (19.3%, 27/140). The frequency of c.109G>A mutation was next to c.235delC found in 25 patients (17.9%, 25/140). CONCLUSION GJB2 mutation is a major cause for NSHL. The most common-spot in Chinese patients with NSHL is c.235delC. The unreported missense mutation is c.344T>G.
Base Sequence ; China ; Connexin 26 ; Connexins ; genetics ; DNA Mutational Analysis ; Gene Deletion ; Hearing Loss ; genetics ; Humans ; Molecular Sequence Data ; Mutation, Missense ; Point Mutation ; genetics

OBJECTIVE: To establish the kanamycin-induced deafness model in SD rats, and to investigate the expression and significance of transmembrane protease, serine 3 (TMPRSS3) in the cochlea following kanamycin ototoxicity. METHODS: A total of 40 male SD rats were randomly divided into 4 groups. The experimental rats received intramuscular kanamycin sulfate for 3, 7, and 14 consecutive days, and the control group were treated with normal saline for 14 days. Auditory brainstem responses (ABR) were obtained before and after the kanamycin administration. The expression of TMPRSS3 in the cochlea was identified and detected by immunohistochemistry and Western blot. RESULTS: Kanamycin-induced deafness model in the SD rats was successfully established. ABR thresholds were increased and the expression of TMPRSS3 in the cochlea was reduced after the kanamycin injection (P<0.01). CONCLUSION TMPRSS3 may play an important role in normal cochlea function and involve in the process of aminoglycoside antibiotics induced deafness.
Animals ; Anti-Bacterial Agents ; toxicity ; Cochlea ; drug effects ; metabolism ; Deafness ; chemically induced ; metabolism ; Disease Models, Animal ; Evoked Potentials, Auditory, Brain Stem ; physiology ; Kanamycin ; toxicity ; Male ; Membrane Proteins ; metabolism ; Rats ; Rats, Sprague-Dawley ; Serine Endopeptidases ; metabolism

OBJECTIVE: To enhance the cure rate and lower the complication rate and the mortality rate through summarizing the clinical features and experiences in diagnosis and therapy of carotid body tumor (CBT). METHOD: Retrospectively analyzed the clinical data of 21 cases (23 sides) of CBT from 1995-2095 occurring in our hospital. RESULT: The accurate diagnosis rates hy using digital subtraction angiography (DSA) and magnetic resonance imaging (MRI) were 100%. Seventeen cases (19 sides) accepted surgical operation with different kinds of procedures. The tumors of 8 cases were simplex isolated from the carotid artery. Both the tumour and the external carotid artery were resected in 9 cases. One case underwent resection of both the internal and external carotid artery and the tumour without carotid reconstruction. One case underwent resection of the internal, external carotid artery and the tumor with reconstruction of the internal carotid artery. No operative mortality was observed. The ventricular arrhythmia which had not been controlled pre-operation occurred in 1 case who was finally self-cured. One case had hoarseness and completely recovered in one week. and 1 case without carotid reconstruction had a frequent headache and gradually recovered in 5 months. The others had no complications. CONCLUSION OSA and MRI are the best methods for diagnosing CBT. Surgery is the first choice concerning the treatment of CBT. Accurate preoperative evaluation, correct therapeutic decision exquisite vascular surgical techniques can help to significantly decrease, even avoid the complications.
Adolescent ; Adult ; Aged ; Angiography, Digital Subtraction ; Carotid Body Tumor ; diagnosis ; diagnostic imaging ; surgery ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Retrospective Studies ; Young Adult

Objective: A subset of intractable allergic rhinitis (iAR) patients experience severe symptoms which cannot be effectively controlled by standard drug therapy and/or antigen specific immunotherapy. In recent decades, endoscopy vidian neurectomy and posterior nasal nerve neurectomy (PNNN) were introduced as treatments of iAR that have shown to be highly successful at symptom management in a number of patients. But some patients experience relapse or suboptimal symptom control postoperation. To improve the effectiveness of PNNN to control iAR, a modified PNNN surgical approach (mPNNN) combined with accessory posterior nasal nerve neurectomy (aPNNN), which called as mPNNN-aPNNN was used. This study aims to compare the effects between mPNNN-aPNNN and PNNN on controlling the symptoms of iAR and evaluate the surgical effectiveness and safety of mPNNN-aPNNN. Methods: The patients with iAR experienced mPNNN-aPNNN or PNNN surgery at the department of Otolaryngology Head and Neck Surgery of the Second Xiangya Hospital, Central South University from January 2018 to December 2019 were analyzed retrospectively. The approach of PNNN, a selective resection of the posterior nasal nerve branches, was modified to the neurectomy of total branches of posterior nasal nerve at the sphenopalatine foramen, and combined the operation of aPNNN in which the accessory posterior nasal nerve at the palatine bone perpendicular plate was resect in our study. Daily Nasal Symptom Scores (DNSS), Total Rhinitis Medication Score (TRMS), and the Rhinoconjunctivitis Qualities of Life Questionnaires Scores (RQLQS) were used to evaluate the complications during the operation and after the operation at the 3rd, 6th, 12th, and 24th month postoperatively. Total Nasal Symptom Scores (TNSS) was used to assess the total effective rate and markedly effective rate of the operations. Results: A total of 140 iAR patients experienced mPNNN-aPNNN or PNNN. Those with concomitant septoplasty and/or inferior turbinate reduction, and were absent during the postoperative follow-up were excluded. The final 62 patients with mPNNN-aPNNN and 34 with PNNN were enrolled. DNSS, TNSS, TRMS, and RQLQS at the postoperation were significantly improved compared with the preoperation in all patients (all P<0.001). Compared with PNNN, the postoperative DNSS, TNSS, and TRMS of mPNNN-aPNNN were obviously improved (all P<0.001). There was a persisted relief of symptoms at the postoperation in all patients with mPNNN-aPNNN. The total effective rate and markedly effective rate at the postoperative 24th month were 100％ and 83.3％, respectively. Furthermore, the postoperative RQLQS decreased significantly (P<0.001). Only 5 sides of all patients (5/192, 2.6％) reported upper palate numbness during the first week after operation, with all recovered spontaneously in 1 month without treatment. No other postoperative complications occurred in mPNNN-aPNNN and PNNN.Conclusion: The surgery of mPNNN-aPNNN improve TNSS more significantly than PNNN. The operation of mPNNN-aPNNN is safe and effective to control iAR symptoms.