Clinical effect analysis of microscopic surgery for epiglottis cysts with coblation.

This study aims to explore the effects and advantages of coblation combined with microscopy to treat epiglottis cysts. Ninety patients with epiglottis cysts were randomly assigned to three groups: the first group: marsupialisation + electric coagulation group, n = 30; the second group: marsupialisation + coblation, n = 30; and the third group: marsupialisation + coblation + microsurgery, n = 30. To compare the cure rate, intraoperative bleeding volume, postoperative pain, operation time and postoperative complications were investigated among these three groups. The comparison among three procedures showed a significant difference for intraoperative bleeding volume, operation time and postoperative pain (P < 0.05), whereas no significant difference was observed for cure rate (P > 0.05). These three procedures are effective in treating epiglottis cysts. Microscopic surgery with coblation has the advantages of less bleeding, short procedure duration, less pain and few complications. Thus, microscopic surgery is worthy of clinical application.

Phenotype and genotype analysis of a Chinese family with prelingual X-linked hereditary hearing impairment.

BACKGROUND: X-linked hearing impairment is clinically and genetically a heterogeneous disease. Although many disorders manifest with hearing loss, a limited number of sex-linked loci and only one gene (POU3F4) have been shown to be implicated in X-linked non-syndromic hearing impairment. In the present study, we have performed a clinical and genetic analysis of a Chinese family with X-linked non-syndromic hearing loss, with emphasis on audiological findings and genomic mapping. METHODS: The clinical features of Family JX01 were evaluated by physical and audiometric examination in eighteen family members. Mutation screening of POU3F4 was identified by polymerase chain reaction (PCR) amplification and sequencing. Molecular evaluation consisted of X-chromosome wide genotyping by microsatellite makers (STR), followed by analyzing using MLINK computer program. RESULTS: Five affected males demonstrated bilateral, symmetrical sensorineural and profound hearing loss. The hearing impairment started prelingual. The female carriers did not have any complain of hearing loss, however, two of them were tested with milder loss with high frequency. No causative mutations in POU3F4 gene were detected by DNA sequencing. Linkage analysis indicated that the responsible gene was linked to locus DXS1227 (maximum lod score = 2.04 at theta = 0). CONCLUSIONS: The affected males in Family JX01 have profound prelingual sensorineural hearing impairment. In addition, two female carriers showed mild to moderate hearing losses. However, none of females complained of any hearing loss. Analysis of hereditary deafness in this family mapped most compatibly to the Xq27.2.

[Mutation screening of MITF gene in patients with Waardenburg syndrome type 2].

Warrgenburg syndrome type 2 (WS2) is the most common autosomal dominantly-inherited syndrome with hearing loss. MITF (microphthalmia associated transcription factor)is a basic-helix-loop-helix-luecine zipper (bHLHZip) factor which regulates expression of tyrosinase, and is involved in melanocyte differentiation. Mutations in MITF associated with WS2 have been identified in some but not all affected families. Here, we report a three-generation Chinese family with a point mutation in the MITF gene causing WS2. The proband exhibits congenital severe sensorineural hearing loss, heterochromia iridis and facial freckles. One of family members manifests sensorineural deafness, and the other patients show premature greying or/and freckles. This mutation, heterozygous deletion c.639delA, creates a stop codon in exon 7 and is predicted to result in a truncated protein lacking normal interaction with its target DNA motif. This mutation is a novel mutation and the third case identified in exon 7 of MITF in WS2. Though there is only one base pair distance between this novel mutation and the other two documented cases and similar amino acids change, significant difference is seen in clinical phenotype, which suggests genetic background may play an important role.

Nonsense mutations in the PAX3 gene cause Waardenburg syndrome type I in two Chinese patients.

BACKGROUND: Waardenburg syndrome type I (WS1) is an autosomal dominant disorder characterized by sensorineural hearing loss, pigmental abnormalities of the eye, hair and skin, and dystopia canthorum. The gene mainly responsible for WS1 is PAX3 which is involved in melanocytic development and survival. Mutations of PAX3 have been reported in familiar or sporadic patients with WS1 in several populations of the world except Chinese. In order to explore the genetic background of Chinese WS1 patients, a mutation screening of PAX3 gene was carried out in four WS1 pedigrees. METHODS: A questionnaire survey and comprehensive clinical examination were conducted in four Chinese pedigrees of WS1. Genomic DNA from each patient and their family members was extracted and exons of PAX3 were amplified by PCR. PCR fragments were ethanol-purified and sequenced in both directions on an ABI_Prism 3100 DNA sequencer with the BigDye Terminator Cycle Sequencing Ready Reaction Kit. The sequences were obtained and aligned to the wild type sequence of PAX3 with the GeneTool program. RESULTS: Two nonsense PAX3 mutations have been found in the study population. One is heterozygous for a novel nonsense mutation S209X. The other is heterozygous for a previously reported mutation in European population R223X. Both mutations create stop codons leading to truncation of the PAX3 protein. CONCLUSIONS: This is the first demonstration of PAX3 mutations in Chinese WS1 patients and one of the few examples of an identical mutation of PAX3 occurred in different populations.

[Mutation screening of the COCH gene in familial and sporadic patients with late onset nonsyndromic sensorineural hearing loss among Chinese population].

OBJECTIVE: To investigate the mutational of the coagulation factor C homology (COCH) gene related to autosomal dominant sensorineural nonsyndromic hearing loss (DFNA) with late onset in Chinese population. METHODS: Peripheral blood samples were collected from he members of 26 DFNA families, members of 19 small DFNA families with un recognized inheritance pattern, and 22 sporadic patients with sensorineural nonsyndromic late onset hearing loss, the hearing loss of all of which occurred during the age range 10 - 40, and 100 normal controls. From different parts of China, these subjects underwent questionnaire survey too. Genomic DNA was isolated, COCH mutation was screened by PCR and sequencing, and restriction endonuclease analysis was used to detect the mutation sites of the COCH gene. The conservation in evolution of the target amino acid sequences was analyzed using CluatalX1.82 software. RESULTS: DNA sequencing of coding regions and exon/intron boundaries of COCH 2 - 12 exons identified a heterozygous G-to-A substitution at position 1625 in exon 12 in a large DFNA family, leading to a C542Y substitution, and a heterozygous T-to-C substitution at position 1535 in exon 12 in a small family, leading to a M512T substitutions. Both the residues of Cys542 and M512 were conserved across human, mouse, chicken, and zebrafish. These mutations were not detected in the 100 control subjects. CONCLUSION: The C542Y and the M512T mutations cause hearing loss in Chinese DFNA families.

[Mapping of gene underlying autosomal dominant non-syndromic hearing loss(DFNA)].

Hereditary non-syndromic sensorineural hearing loss is a genetically highly heterogeneous group of disorders. To date, at least 50 loci for autosomal dominant non-syndromic sensorineural hearing loss (DFNA) have been identified by linkage analysis. Here we report a huge family with late onset autosomal dominant hereditary non-syndromic hearing loss. In this family, 73 of 170 family members have been conducted physical examination, pure-tone audiometry, immittance testing and auditory brainstem response testing (ABR). The results indicated that 39 of 73 tested family members have sensorineural hearing loss in various degrees. No associated visible abnormalities in other systems were found in this family. After exclusion of the 14 known DFNA loci with markers from the Hereditary Hearing Loss Homepage (URL: http://dnalab-www.uia.ac.be/dnalab/hhh), a genome wide scan was carried out using 382 highly informative microsatellite markers at approximately 9.2 cM intervals throughout the genome. Linkage analysis was carried out under a fully penetrant autosomal dominant mode of inheritance with no phenocopies. A maximum two-point LOD score of 6.69 at theta=0 was obtained for marker D14S1040. Haplotype analysis placed the locus within a 7.6 cM genetic interval defined by marker D14S1021 and D14S70, overlapping with the DFNA9 locus.

[Clinical features of a Chinese pedigree with Waardenburg syndrome type 2].

OBJECTIVE: To investigate detailed clinical features of a Chinese pedigree with Waardenburg syndrome type 2. METHODS: Members of this pedigree were interviewed to identify personal or family medical histories of hearing loss, the use of aminoglycosides, and other clinical abnormalities by filling questionnaire. The audiological and other clinical evaluations of the proband and other members of this family were conducted, including pure-tone audiometry, immittance and auditory brain-stem response and ophthalmological, dermatologic, hair, temporal bone CT examinations. RESULTS: This family is categorized as Waardenburg syndrome type 2 according to its clinical features. It's an autosomal dominant disorder with incomplete penetrance. The clinical features varied greatly among family members and characterized by sensorineural hearing loss, heterochromia irides, freckle on the face and premature gray hair. Hearing loss can be unilateral or bilateral, congenital or late onset in this family. CONCLUSION: This Chinese family has some unique clinical features comparing with the international diagnostic criteria for Waardenburg syndrome. This study may provide some evidences to amend the diagnostic criteria for Waardenburg syndrome in Chinese population.