视网膜母细胞瘤中P16基因蛋白表达的免疫组化研究

目的研究视网膜母细胞瘤肿瘤组织中P16蛋白的表达状况,并探讨它与RB病理分化程度、视神经浸润能力和预后之间的关系。方法采用免疫组化SABC法。结果17例正常视网膜组织中P16蛋白表达阳性率明显高于49例RB肿瘤组(P＜0.05);13例分化型RBP16蛋白阳性表达率明显高于36例未分化型RB(P＜0.05);31例视神经未浸润组RBP16阳性表达率明显高于18例视神经浸润组(P＜0.05);RB存活组P16蛋白阳性表达率与死亡组差异无显著性(P＞0.05)。结论RB中可能存在P16基因异常,所致的P16蛋白失表达与RB的组织学分型和视神经浸润能力的获得有关,但尚不能认为与RB的预后有关。     

口腔粘膜鳞癌组织中P53和nm23蛋白的表达分析

目的研究口腔粘膜鳞癌组织中P     

人听觉器官线粒体DNA4977缺失与老年聋的关系

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鼻息肉组织中Th1、Th2细胞因子的表达及其意义

目的探讨IL-4、IL-5等8种细胞因子在鼻息肉发病中的作用和对鼻息肉治疗的意义。方法采用酶联免疫吸附实验(ELISA)法检测25例鼻息肉患者鼻息肉组织中Th     

60钴辐射致豚鼠内耳前庭终器损害的功能研究及超微结构观察

目的为了观察60钴对内耳前庭终器的影响。方法本实验对豚鼠耳颞部行60钴50Gy辐射,在结束辐射后4个小时、第3天、第5天对实验鼠行正弦摆动、旋转及4℃冰水诱发眼震检测。并对内耳前庭终器标本行扫描和透射电镜观察。结果50Gy60钴辐射后4小时已有前庭功能损害,随结束辐射后时间推移,前庭功能损害随之加剧。电镜观察可见内耳前庭器毛细胞纤毛有散乱及倒伏,线粒体内质网出现肿胀崩解,细胞可呈空泡样变。前庭神经末梢可见髓鞘水肿和髓鞘破坏。结论耳颞部60钴辐射可造成内耳前庭终器结构与功能的损害。     

Cochlear microphonic evidence for mechanical propagation of distortion products (ƒ2 − ƒ1) and (2ƒ1 − ƒ2)

The present cochlear microphonic (CM) study was undertaken to help resolve a conflict in the literature regarding cochlear nonlinear properties. The CM studies of Dallos and his coworkers have concluded that “(up to 70–80 dB SPL [re 20 μPa]), all orders of distortion components … do not seem to be accompanied by traveling waves of their own” (Dallos P. (1973): The Auditory Periphery: Biophysics and Physiology. Academic Press, New York). However, studies of spatial distributions of cochlear nerve fiber responses, acoustic distortion products in the ear canal, and related modeling studies of Kim et al. (Kim D.O. and Molnar C.E. (1975): in: The Nervous System. Vol. 3: Human Communication and Its Disorders. Editor: D.B. Tower, Raven Press, New York; Kim D.O., Molnar C.E. and Matthews J.W. (1980): J. Acoust. Soc. Am. 67, 1704–1721) have led to conclusions to the contrary. In the present study, CM data were obtained from the second and third turns of the chinchilla cochlea using fluid-filled glass micropipettes in scala media and nichrome wire electrodes in scala vestibuli and scala tympani. We sought responses containing predominant distortion products (?₂ ? ?₁) and (2?₁ ? ?₂) by fixing a distortion frequency (?_d) near the characteristic frequency (CF) of the recording site and varying the stimulus frequencies ?₁ and ?₂ and SPLs (with L₁ = L₂). By subsequently varying the distortion frequency around the CF, e.g., fixing ?₁ well above the CF and varying ?₂, we measured the tuning characteristics of the distortion products (?₂ ? ?₁) and (2?₁ ? ?₂). Tuning characteristics of single-tone responses were measured by applying single-tone stimuli of various frequencies with a constant SPL at the eardrum. We have observed, with SPLs as low as 25 dB, that these distortion products in CM display tuning similar to the single-tone response which is consistent with the above neural results. From these tuning similarities, we conclude that our CM data reflect the presence of mechanically propagated distortion products at low SPLs, in agreement with the above studies by Kim et al. Validity of our results is supported by the sensitivity and sharp tuning of our CM data and, in the case of the scala media recordings, by the presence of a normal d.c. endolymphatic potential. Plausible explanations for the opposing conclusions of previous studies of Dallos et al. and the present study are discussed.     

Particular distribution of the GJB2/GJB6 gene mutations in Mexican population with hearing impairment

Background

Hereditary sensorineural hearing loss (SNHL) is a genetically heterogeneous disorder worldwide. Mutations in the GJB2 gene are a frequent cause of hereditary SNHL. There is a prevalence of certain mutations in various populations which suggests that specific mutations may be influenced by ethnic background.

Objective

To analyze the prevalence of GJB2, GJB6 mutations in several geographic areas of Mexico in patients with hereditary SNHL.

Materials and methods

One hundred and forty Mexican unrelated propositi with prelingual SNHL were included in the study. All patients had three previous generations born in Mexico and belonged to no specific ethnic group. Analyses of the GJB2 and GJB6 genes and mt.1555A < G were performed in all subjects.

Results

Twenty-three homozygous mutations, 57 heterozygous mutations, 1 double heterozygous (GJB2/GJB6) and 59 wild-type genotypes in the GJB2 gene were observed. Three patients had the homozygous c.del35 mutation whereas 26 patients were heterozygous for this gene defect. Only one patient with the GJB6 gene deletion was present (it includes the double heterozygous GJB2/GJB6). The mt.1555A > G mutation was not detected.

Conclusion

We found a great variety of mutations depending on the analyzed region in patients with SNHL; 57.86% of patients had affection in one or two alleles in GJB2 or GJB6 genes whereas 42.14% were wild-type. In some cases, allele distribution depended on region. Molecular studies of more genes involved in hereditary non-syndromic SNHL are required to completely confirm the molecular basis of hearing loss in Mexican population.     

Screening of SLC26A4, FOXI1 and KCNJ10 genes in unilateral hearing impairment with ipsilateral enlarged vestibular aqueduct

Objective

To investigate the implication of SLC26A4, FOXI and KCNJ10 genes in unilateral hearing impairment associated with ipsilateral inner ear malformation (Enlargement of the vestibular aqueduct and/or Mondini dysplasia).

Methods

We have gathered 25 patients presenting unilateral hearing impairment and ipsilateral enlarged vestibular aqueduct. For each of the patients, we have analyzed SLC26A4, FOXI1 and KCNJ10 genes sequences.

Results

The analysis of SLC26A4 revealed only eight heterozygous SLC26A4 sequence variants, three of them being novel (p.Met147Ile, p.Asn538Asn and p.Leu627Arg). None of the patients carried a second mutation on the other allele. Moreover, the SLC26A4 locus was excluded by segregation analysis in two families. No mutations were present in FOXI1 and KCNJ10 genes.

Conclusions

Together, these data suggest that SLC26A4, FOXI1 and KCNJ10 are not major determinants in unilateral deafness and enlarged vestibular aqueduct compared with their implication in Pendred syndrome and non-syndromic bilateral enlarged vestibular aqueduct.     

Distortion in the cochlea: Acoustic f2−f1 at low stimulus levels

The stimulus level and frequency dependence of the quadratic difference tone (QDT) measured as an otoacoustic emission in the ear canal has been investigated in the guinea pig and compared with simultaneously measured cubic difference tone (CDT) and with the round window electrical response. Acoustic QDT level tended to be highly labile. Growth of the ear canal response with covaried stimuli was very gradual (slope < 0.5). Acoustic and CM responses showed similar behaviour when f₂ alone was incremented. The QDT was strongly dependent on stimulus frequency separation for high frequency stimuli. It is suggested that, at low stimulus levels and high frequencies, the acoustic QDT may originate in the ‘tonic’ motile responses of outer hair cells as they follow the envelope of the two-tone stimulus.     

CD43CD20及总IgE在鼻息肉组织中表达的研究

目的探讨CD     

Tonsil cryptolysis usingCO2 Swiftlase

Treatment for inflammation of the tonsils has taken a variety of therapeutic forms over the years, ranging from the application of iodine and massage in the preantibiotic era to the tonsillectomy, which prevails today. The architecture of the cryptic tonsil, its clinical implications, and the rationale for a conservative, yet effective treatment modality focusing on the tonsillar crypts are addressed in this article. Also described are the procedures and results of a retrospective clinical study in which conventional tonsillectomy was compared with CO₂ SwiftLase cryptolysis. Although our observations are not based on a prospective, controlled study, the information disseminated here may be useful to otolaryngologists who routinely perform tonsillectomy in their practice, using conventional surgical dissection methods or the CO₂ laser. According to our experience with a population of 120 patients, cryptolysis offers some clear advantages, particularly when performed with the SwiftLase apparatus. The procedure can be performed safely in an ambulatory surgery or office setting under local anesthesia. The cooperative patient avoids the cost and risks of general anesthesia. Limited tissue destruction significantly reduces operative and postoperative complications, discomfort, and recovery time. To conclude, CO₂ SwiftLase cryptolysis is a safe and cost-effective method of treating tonsil pathology without unnecessary sacrifice of the organ, and undue risks and expenses to the patient.^11,12