Objective To investigate the clinical application of multiplex allele-specific PCR assays for simultaneous detection of the mitochondrial 12S rRNA A1555G and C1494T mutations associated with aminoglycoside-induced hearing impairment.Methods Three standard plasmids of different genotypes (wild-type, A1555G mutant and C1494T mutant) were constructed for templates and allele-specific primers aiming directly at wild-type and mutant of mitochondrial DNA nt1555 and nt1494 were designed for developing a multiplex allele-specific PCR technique to detect the A1555G and C1494T mutations.Then the method was applied to clinical screening of 138 non-syndromic hearing loss subjects and confirmed by DNA sequencing.Results Multiplex allele-specific PCR was successfully applied to the detection of A1555G and C1494T mutations in a cohort of 138 Han Chinese genetically unrelated hearing-loss subjects.Finally, 11(7.97%) unrelated affected subjects harbored the A1555G and C1494T mutations in the 12S rRNA gene(10 cases for A1555G and 1 cases for C1494T), which was well consistent with results of DNA sequencing [7.97%(11/138), Kappa=1.000, P＜0.01].Conclusion This study indicates that the multiplex allele-specific PCR assay is useful, convenient and reliable in the detection of the A1555G and C1494T mutations, which could identify the subjects at risk and effectively prevent of aminoglycoside-induced hearing loss.

To realize the accurate positioning and quantitative volume measurement of tumor in head and neck tumor CT images, we proposed a level set method based on augmented gradient. With the introduction of gradient information in the edge indicator function, our proposed level set model is adaptive to different intensity variation, and achieves accurate tumor segmentation. The segmentation result has been used to calculate tumor volume. In large volume tumor segmentation, the proposed level set method can reduce manual intervention and enhance the segmentation accuracy. Tumor volume calculation results are close to the gold standard. From the experiment results, the augmented gradient based level set method has achieved accurate head and neck tumor segmentation. It can provide useful information to computer aided diagnosis.
Diagnosis, Computer-Assisted ; Head and Neck Neoplasms ; pathology ; Humans ; Tomography, X-Ray Computed ; Tumor Burden

OBJECTIVE To determine the distribution of allergens in patients with allergic rhinitis in Wenzhou area. METHODS Patients with AR symptoms from January 2013 to December 2014 were given skin prick test (SPT). The clinical data about SPT was retrospectively colleceted to analyze SPT results. RESULTS 1. Among 2991 individuals, the total positive rate of SPT was 82.0%, with Dermatophagoides farinae (Der. f) and Dermatophagoides pteronyssinus (Der.p) as the most common allergens; the positive rate of inhalant allergen was obviously higher than that of ingestive ones, with significantly statistical difference(χ2=2006.557,P<0.01). Most of patients were allergic to double allergens; the intensity of Der.f and Der.p mainly presented as (++++), with no significant difference(Z=-0.391, P=0.696). 2. There was significant difference of variation with seasons(χ2=34.254, P<0.01). 3. No significant difference of positive rate were observed in different AR-courses(χ2=16.102, P<0.01). 4. Significant difference of positive rate was found among different age-groups; The positive rate was increased along with growing age, got peak at group of 10-12 years old, and then got down after that. CONCLUSION Dust mite was the main allergen coursed AR in Wenzhou area. Seasons and age were two important factors effecting on positive of SPT and onset of AR. The positive rate of allergens was related to age.