Assessment of the potential ototoxicity of high-dose celecoxib, a selective cyclooxygenase-2 inhibitor, in rats

OBJECTIVE

To evaluate the potential ototoxicity of high-dose celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor.

STUDY DESIGN

Prospective animal study.

SETTING

Laboratory.

METHODS

Twenty adult male Sprague Dawley rats were divided into 2 groups for hearing and tinnitus tests, respectively. The auditory brain-stem response (ABR) and the gap prepulse inhibition of acoustic startle (GPIAS) were used as indicators of hearing loss and tinnitus, respectively, and were measured before and at 2, 4, 6, 8, 12, 24, and 48 hours after administration of celecoxib (2 g/kg) via gavage.

RESULTS

ABR threshold and wave III latencies did not increase significantly at any frequency following celecoxib administration, at any time point (P > .05). GPIAS remained below 30% after celecoxib, from a baseline of 20.03% ± 3.62%; no change was significant.

CONCLUSION

High-dose celecoxib (2 g/kg), a selective COX-2 inhibitor, did not cause hearing loss or tinnitus in Sprague Dawley rats within 48 hours of administration. Further studies are needed to explore the roles played by COX-related mechanisms when nonselective COX inhibitors induce ototoxicity.

No association between the ApoE ε2 and ε4 alleles and the risk of obstructive sleep apnea: A systematic review and meta-analysis

Apolipoprotein E (ApoE) gene ε2 and ε4 alleles have been reported to be associated with the risk of obstructive sleep apnea (OSA); however, the results are controversial. Thus, we performed a meta-analysis to obtain a more precise estimate of the associations by pooling sporadic, inconsistent and small-sample-size studies. Electronic databases such as PubMed and Embase were searched to identify eligible studies focusing on the association between ApoE polymorphisms and susceptibility to OSA before April 2014. The associations were assessed by odds ratio (ORs) with 95% confidence intervals (CIs). The Begg and Egger's test was used to evaluate publication bias. Ten eligible studies (1,696 cases/2,216 controls for the ε2 allele and 2,449 cases/5,592 controls for the ε4 allele) were included in the meta-analysis. An association between the ApoE ε2 and ε4 alleles and OSA was not found in the overall population (OR=0.97, 95% CI: 0.75-1.25; OR=1.09, 95% CI: 0.86-0.38 for ApoE ε2 and ε4, respectively). Significant heterogeneity (ε2: I²=36.6%, P=0.16; ε4: I²=69.7%, P=0.001) was observed across studies, however, heterogeneity could not be explained by variations in mean age, body mass index, apnea hypopnea index, gender, ethnic background, or the ApoE ε2 and ε4 alleles. No evidence of publication bias was found according to the Begg and Egger's test. In conclusion, our findings show that the ApoE ε2 and ε4 alleles have no significant associations with OSA susceptibility based on available data.

Human papillomavirus infection in 674 Chinese patients with laryngeal squamous cell carcinoma

Objectives

Previous reports suggest a strong association between human papillomavirus (HPV) and the etiology of laryngeal squamous cell carcinoma (LSCC). However, clinical data regarding the HPV infection rate among LSCC patients remain largely inconsistent.

Methods

In total, 674 LSCC patients from three major hospitals in Shanghai were enrolled in this study. We determined the patients' HPV infection status using immunohistochemistry and the GenoArray HPV genotyping assay and calculated their long-term survival rate using the Kaplan-Meier method.

Results

The total P16-positive rate according to immunostaining results was 7.57% (51/674). None of the P16-negative patients were HPV-positive according to the HPV genotyping test. The rate of HPV infection among patients with LSCC was 4.9% (33/674). HPV infection was more common among nonsmokers (P<0.05), nondrinkers (P<0.05), and patients with supraglottic LSCC (P<0.05). Of the 33 HPV-positive patients, 28 (84.8%) were infected with HPV-16, 2 with HPV-18, 1 with HPV-31, 1 with HPV-33 and 1 with HPV-45. The 3-year overall survival rate and progression-free survival rate were higher in HPV-positive than HPV-negative patients, but the difference was not statistically significant (76.3% vs. 70.7%, P = 0.30 and 65.1% vs. 58.3%, P = 0.37, respectively).

Conclusion

HPV was not a main causal factor in LSCC carcinogenesis in this Chinese population. HPV infection did not alter patients' overall survival or progression-free survival rates in this study.

Evaluation of a 2-channel portable device and a predictive model to screen for obstructive sleep apnea in a laboratory environment

BACKGROUND

Various portable monitors for identifying obstructive sleep apnea (OSA) have been investigated and reported to enable accurate recording of OSA severity. However, more information is needed from different populations. This study was conducted to evaluate the efficiency of a portable 2-channel sleep apnea device (SleepView) for screening OSA in the Chinese population.

METHODS

Ninety-three consecutive subjects underwent simultaneous SleepView testing and laboratory polysomnography (PSG) monitoring. Data were collected and blindly analyzed. The efficiency of the SleepView device and a newly established predictive model for identifying OSA was evaluated in comparison with PSG.

RESULTS

Good agreement was evident between the SleepView and PSG based on the apnea-hypopnea index (AHI; r(2) = 0.84, P < .01). The median AHI yielded by the SleepView was higher than that of PSG: 33.2 (interquartile range of 10.5-53.3) versus 19.2 (interquartile range of 5.2-53.6). The sensitivity and specificity of the SleepView for a PSG AHI of ≥ 5 were 80.28% and 95.45%, respectively, and the cutoff was 16.8. The area under the receiver operating curve for PSG AHIs of ≥ 5, > 15, and > 30 was 0.923, 0.924, and 0.979, respectively. When the AHI and oxygen desaturation index calculated by the SleepView were combined with waist circumference, the new predictive model showed a higher sensitivity of 92.96% and a specificity of 95.45% for a PSG AHI of ≥ 5, and the corresponding area under the receiver operating curve was 0.983.

CONCLUSIONS

The SleepView device exhibited acceptable diagnostic accuracy for OSA in the Chinese population, especially in the severe OSA group. A practical predictive model comprising waist circumference, AHI, and oxygen desaturation index obtained with the SleepView was highly effective for screening even mild OSA. This simple and practical device may serve as a useful tool to screen for OSA. Further studies are required to validate the diagnostic efficiency of the SleepView in the home environment and in different populations.

Characterization of major histocompatibility complex class I allele polymorphisms in common marmosets

Currently, little information is available for major histocompatibility complex (MHC)-I that conditions the T-cell response of marmosets. In this study, 471 clones of MHC-I cDNA sequences were isolated from 12 marmosets. Twenty full-length sequences of class I G (Caja-G) alleles were obtained from these marmosets, 15 of them were novel. Among these 20 Caja-G alleles, 10 were found in individual animals while the rests were in two to four marmosets, but none was common to all animals. Ten marmosets possessed one to three Caja-G alleles, and two marmosets carried five or six alleles, which suggested that the Caja-G locus was duplicated in marmoset's genome. The high polymorphisms of Caja-G sequences provided important information helpful for understanding the cellular immune response in virus-infected marmosets.

In vivo overexpression of X-linked inhibitor of apoptosis protein protects against neomycin-induced hair cell loss in the apical turn of the cochlea during the ototoxic-sensitive period

Aminoglycoside-induced cochlear ototoxicity causes hair cell (HC) loss and results in hearing impairment in patients. Previous studies have developed the concept of an ototoxicity-sensitive period during which the cochleae of young mice are more vulnerable to auditory trauma than adults. Here, we compared neomycin-induced ototoxicity at the following four developmental ages in mice: postnatal day (P)1–P7, P8–P14, P15–P21, and P60–P66. We found that when neomycin was administered between P8 and P14, the auditory brainstem response threshold increase was significantly higher at low frequencies and HC loss was significantly greater in the apical turn of the cochlea compared to neomycin administration during the other age ranges. Quantitative real-time PCR (qPCR) data revealed that the expression of apoptotic markers, including Casp3 and Casp9, was significantly higher when neomycin was injected from P8 to P14, while the expression of the X-linked inhibitor of apoptosis protein (XIAP) gene was significantly higher when neomycin was injected from P60 to P66. Because XIAP expression was low during the neomycin-sensitive period, we overexpressed XIAP in mice and found that it could protect against neomycin-induced hearing loss at low frequencies and HC loss in the apical turn of the cochlea. Altogether, our findings demonstrate a protective role for XIAP against neomycin-induced hearing loss and HC loss in the apical turn of the cochlea during the ototoxic-sensitive period, and suggest that apoptotic factors mediate the effect of neomycin during the ototoxic-sensitive period.

Nocturnal snoring sound analysis in the diagnosis of obstructive sleep apnea in the Chinese Han population

PURPOSE

Loud snoring is one of the principle symptoms of obstructive sleep apnea (OSA). Snoring sound analysis is a potentially cost-effective, reliable alternative for the diagnosis of OSA. However, no investigation has determined the accuracy of snoring signal analysis for the diagnosis of OSA in the Chinese Han population. Therefore, we investigated whether whole-night snoring detection and analysis aids the diagnosis of OSA using a new snore analysis technique.

METHODS

Snoring sounds were recorded using a non-contact microphone and polysomnography (PSG) was performed simultaneously throughout the night. We randomly selected 30 subjects each from four groups based on the severity of OSA. The rhythm and frequency domain of the snoring signal were analyzed based on frequency energy endpoint detection (FEP) and the Earth mover's distance (EMD), for each subject to harvest the EMD-calculated Apnea-Hypopnea Index (AHIEMD). Finally, we compared the AHIEMD with the PSG-monitored AHI (AHIPSG).

RESULTS

The accuracy of the AHIEMD compared with the AHIPSG was 96.7, 86.7, 86.7, and 96.7% in non-, mild, moderate, and severe OSA patients, respectively. AHIEMD was correlated with AHIPSG (r(2) = 0.950, p < 0.001). The area under the receiver operating characteristic curve values for OSA detection was 0.974, 0.957, and 0.997 for AHIEMD thresholds of 5, 15, and 30 events/h, respectively. Bland-Altman analysis revealed 91.7% agreement of AHIEMD with AHIPSG.

CONCLUSIONS

This new method for identifying OSA by analyzing snoring is feasible and reliable in the Han population. The snoring sound-based technique appears to be a promising tool for OSA screening and diagnosis.

Comparative study of the efficacy of the canalith repositioning procedure versus the vertigo treatment and rehabilitation chair

CONCLUSION

Vertigo treatment and rehabilitation chair (TRV) may be suggested as the first choice for patients with posterior canal benign paroxysmal positional vertigo (p-BPPV).

OBJECTIVE

To investigate the short- and long-term treatment efficacy of the canalith repositioning procedure (CRP) versus TRV for patients with p-BPPV.

METHODS

A total of 165 patients with unilateral p-BPPV were assigned to either the CRP group or the TRV group. Patients were assessed at 1 week, 4 weeks, 3 months, and 6 months after their first treatment. The numbers of treatment sessions required for successful repositioning in both groups at 4 weeks, 3 months, and 6 months were recorded.

RESULTS

Treatment efficacy of patients in the TRV group was significantly better than that of patients in the CRP group 1 week after the first treatment. The number of treatment sessions needed for successful repositioning was significantly lower in the TRV group than in the CRP group at 4 weeks and 3 months after the first treatment.

Humoural immune response and pathological analysis in patients with false immune diagnosis of cystic echinococcosis

The patients with false immune diagnosis of hydatid disease were investigated for the humoural immune response to analyse the possible reasons and mechanism leading to false immune diagnosis. Two hundred and thirty-nine patients with nature-unknown cysts and 30 healthy controls were detected by immunological assays (four hydatid antigen-based immunogold filtration assay and enzyme-linked immune absorbent assay) and ultrasound. Sensitivity of and specificity of immunological assay and ultrasound were calculated, respectively. The serological diagnosis was compared with surgical pathology to screen the patients with false immune diagnosis for the immunoglobulin measurement and pathological analysis. The history and cyst characteristics were also reviewed. The results indicate the immunoglobulin has little influence on false immunodiagnosis. The false-negative immunodiagnosis was caused by the cysts' inactive status while the false positive caused by previous rupture, antigen cross-reaction. The clinical diagnosis of cystic echinococcosis requires a combination of immunodiagnosis and ultrasonography, which is the necessary complementary confirmation.

[Complementary self-treatment for posterior canal benign paroxysmal positional vertigo]

OBJECTIVE

To examine the value of self-treatment for Posterior canal benign paroxysmal positional vertigo (PC-BPPV). The treatment effect was compared between patients treated with modified Epley in outpatient clinic combined with self treatment at home and patients treated by modified Epley alone.

METHOD

A randomized controlled trial were carried out in the Department of Otolaryngology Head and Neck Surgery, the Affiliated Sixth People's Hospital of Shanghai Jiao Tong University from December 2012 to May 2013. 147 out of 150 patients with unilateral idiopathic BPPV-PSC were enrolled in follow-up. Among which, 73 patients were allocated in modified Epley-alone group and 74 were allocated in slef-treatment group.

RESULT

The success rate was 53.4% in modified Epley-alone group vs 83.8% in self-treatment group (P < 0.01) after 1 week treatment. In the modified Epley-alone group,the success rate of hand repositioning group and chair-assisted repositioning group was 45.9% vs 61.1% (P > 0.05), the risk rate was 0.752, 95% CI (0.486 - 1.163). In the self-treatment group, the success rate of hand repositioning group and chair-assisted repositioning group was 87.5% vs 81.0% (P > 0.05), the risk rate was 1.081, 95% CI (0.888-1.316). Incidence rate of serious complications was 0% in the modified Epley-alone group and 1.3% in the self-treatment group (P > 0.05).

CONCLUSION

Complementary self-treatment with modified Epley maneuver treated PC-BPPV sooner and more effectively, Compared with modified Epley maneuver alone. And its incidence rate of serious complications didn't increase. Chair-assisted repositioning showed better result than hand repositioning alone, and self-treatment at home can reduce the effect of the gap. We found that complementary self-treatment with modified Epley maneuver had more benefits for patients with PC-BPPV.

Effect of continuous positive airway pressure on lipid profile in patients with obstructive sleep apnea syndrome: a meta-analysis of randomized controlled trials

BACKGROUND

Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for development of dyslipidemia. Continuous positive airway pressure (CPAP) is the first-line treatment for OSAS. However, it is unclear whether CPAP improves lipid metabolism.

OBJECTIVES

To review the effect of CPAP on lipid profile of patients with OSAS.

METHODS

We searched PubMed, Embase, and the Cochrane Library to identify eligible articles published prior to October 30, 2013. Six randomized controlled trials (RCTs) were subjected to meta-analysis using Comprehensive Meta-Analysis software.

RESULTS

Six RCTs meeting the inclusion criteria were enrolled. The total numbers of measurements of total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol, in CPAP intervention patients and sham/control groups, were 370 and 371, 330 and 328, 276 and 274, and 269 and 266 respectively. The pooled estimate of the difference in the mean TC level between the CPAP and sham CPAP/control groups was significantly different (-0.15 [95% confidence interval, -0.27 to -0.03]; p = 0.01). Subgroup analysis revealed that OSAS patients of younger age, who were more obese, and who had been treated via CPAP for a longer duration, showed a significant decrease in TC levels (the differences in the means were -0.27, -0.24, and -0.20; and the p values 0.001, 0.01, and 0.04, respectively).

CONCLUSION

We confirmed that CPAP decreases the TC level, especially in OSAS patients who are younger, more obese, and who use CPAP for a longer period. CPAP did not alter TG, LDL, or HDL levels, suggesting that CPAP may have no clinically important effect on lipid metabolism.

The behavior of residual tumors and facial nerve outcomes after incomplete excision of vestibular schwannomas

OBJECT

The authors evaluated the behavior of residual tumors and facial nerve outcomes after incomplete excision of vestibular schwannomas (VSs).

METHODS

The case records of all patients who underwent surgical treatment of VSs were analyzed. All patients in whom an incomplete excision had been performed were analyzed. Incomplete excision was defined as near-total resection (NTR), subtotal resection (STR), and partial resection (PR). Tumors in the NTR and STR categories were followed up with a wait-and-rescan approach, whereas the tumors in the PR category were subjected to a second-stage surgery and were excluded from this series. All patients included in the study underwent baseline MRI at the 3rd and 12th postoperative months, and repeat imaging was subsequently performed every year for 7-10 years postoperatively or as indicated clinically. Preoperative and postoperative facial function was noted.

RESULTS

Of the 2368 patients who underwent surgery for VS, 111 patients who had incomplete excisions of VSs were included in the study. Of these patients, 73 (65.77%) had undergone NTR and 38 (34.23%) had undergone STR. Of the VSs, 62 (55.86%) were cystic and 44 (70.97%) of these cystic VSs underwent NTR. The residual tumor was left behind on the facial nerve alone in 62 patients (55.86%), on the facial nerve and vessels in 2 patients (1.80%), on the facial nerve and brainstem in 15 patients (13.51%), and on the brainstem alone in 25 patients (22.52%). In the 105 patients with normal preoperative facial nerve function, postoperative facial nerve function was House-Brackmann (HB) Grades I and II in 51 patients (48.57%), HB Grade III in 34 patients (32.38%), and HB Grades IV-VI in 20 patients (19.05%). Seven patients (6.3%) showed evidence of tumor regrowth on follow-up MRI. All 7 patients (100%) who showed evidence of tumor regrowth had undergone STR. No patient in the NTR group exhibited regrowth. The Kaplan-Meier plot demonstrated a 5-year tumor regrowth-free survival of 92%, with a mean disease-free interval of 140 months (95% CI 127-151 months). The follow-up period ranged from 12 to 156 months (mean 45.4 months).

CONCLUSIONS

The authors' report and review of the literature show that there is undoubtedly merit for NTR and STR for preservation of the facial nerve. On the basis of this they propose an algorithm for the management of incomplete VS excisions. Patients who undergo incomplete excisions must be subjected to follow-up MRI for a period of at least 7-10 years. When compared with STR, NTR via an enlarged translabyrinthine approach has shown to have a lower rate of regrowth of residual tumor, while having almost the same result in terms of facial nerve function.

Biochemical changes and oxidative stress induced by zearalenone in the liver of pregnant rats

The aim of the present research was to examine the toxic influence of different doses of zearalenone (ZEN) on the liver, especially oxidative stress induced by ZEN on the liver. A total of 48 pregnant Sprague-Dawley rats were randomly assigned into 4 treatments groups with 12 animals in each. The rats were fed with a normal diet treated with 0 mg/kg (control), 50 mg/kg (treatment 1), 100 mg/kg (treatment 2), or 150 mg/kg (treatment 3) ZEN in feed on gestation days (GDs) 0–7 and then all the rats were fed with a normal diet on GDs 8–20. The experimental period lasted 21 days. The results showed that exposure to ZEN induced increase in aspartate amino transferase, alanine aminotransferase, and alkaline phosphatase activities and decrease in total protein and albumin content in a dose-dependent manner and also induce decrease in superoxide dismutase and glutathione peroxidase activities and increase in malondialdehyde content in a dose-dependent manner in the serum and the liver. The increased transcription of cytochrome P450 2E1 (CYP2E1) was detected in the liver after exposure to ZEN. These results suggested that ZEN not only caused damage in the liver of pregnant rats in a dose-dependent manner but also induced the messenger RNA expression of CYP2E1 in the liver.

[Clinical analysis of 29 cases of cervical necrotizing fasciitis]

OBJECTIVE

To study the experience of clinical features and treatment of deep cervical necrotizing fasciitis.

METHOD

All 29 cases of cervical necrotizing fasciitis patients were diagnosed by CT, 12 cases underwent tracheostomies, lateral neck incisions and drainage operations, the other 17 patients underwent lateral neck incisions and drainage operations. Sequently washing, dressing changes and anti infection treatments were taken.

RESULT

Twenty-eight cases were cured, 1 cases died. During a follow-up of half a year,no relapse.

CONCLUSION

When patient was sufferd the cervical necrotizing fasciitis, surgical operation for exploration should be taken as soon as possible,and incision and drainage in the treatment of cervical abscess would obtain a satisfactory curative effect, which would prevent serious complications.

Comparison of hearing results of malleovestibulopexy and total ossicular replacement prosthesis for chronic otitis media patients with a mobile stapes footplate

OBJECTIVE

This study aimed to assess differences in hearing outcomes using the malleostapedotomy or malleovestibulopexy (MVP) and total ossicular replacement prosthesis (TORP) techniques in chronic otitis media patients with a mobile stapes footplate.

STUDY DESIGN

Case series with planned data collection.

SETTING

A university medical center.

SUBJECTS AND METHODS

In total, 27 patients with chronic otitis media at the Sixth Hospital affiliated with Shanghai Jiao Tong University, between January and October 2010, were included. All patients had destruction of incus and stapes superstructures and a mobile stapes footplate. In all patients, surgery was performed under general anesthesia by a retroauricular approach. After the lesions were removed completely, ossicular reconstruction was performed using 1 of the techniques. In all patients, pure-tone audiograms were assessed before and 12 months after surgery.

RESULTS

Thirteen patients underwent MVP surgery, whereas the other 14 cases received traditional TORP surgery. All patients showed improvements in functional hearing after surgery. Although the numbers of ears that had closure of the air-bone gap within 20 dB in the MVP group were not statistically significantly higher than those in the TORP group (Fisher's exact test, P > .05), the average postoperative gain of the MVP group was significantly higher than that of the TORP group (t test, P < .05).

CONCLUSION

Functional hearing in chronic otitis media patients with a mobile stapes footplate was better in those who underwent MVP surgery than in those who underwent TORP surgery.

A systematic review and meta-analysis of the association between serotonergic gene polymorphisms and obstructive sleep apnea syndrome

Background

5-Hydroxytryptamine receptor (5-HTR) and 5-hydroxytryptamine transporter (5-HTT) gene polymorphisms have been reported to be associated with susceptibility to obstructive sleep apnea syndrome (OSAS). The associations, derived from sporadic, inconsistent, small-sample-size studies, need to be evaluated further in a meta-analysis.

Methods

Relevant studies were identified by searching PubMed, Embase, The Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu. Eligible data were extracted from each included study. Odds ratios (ORs) were calculated using a fixed-effects or a random-effects model. The ORs and 95% confidence interval (CI) were used to assess the strength of the association between serotonergic gene polymorphisms and OSAS in the dominant and recessive models, as well as alleles. The Q statistic was used to evaluate homogeneity and Begg’s test was used to assess publication bias.

Results

Eight studies were finally included in the meta-analysis of the association between 5-HTR2A gene variants (including 102T/C and 1438G/A), 5-HTT gene polymorphisms (including 5-HTT gene-linked promoter region (5-HTTLRP), and serotonin transporter intron 2 variable number tandem repeat (STin2VNTR) and OSAS risk. The G allele of 5-HTR2A 1438G/A, long 5-HTTLPR, and 10-tandem-repeats STin2VNTR were shown to increase OSAS susceptibility, with ORs of 2.33 (A vs. G, 95% CI 1.48–3.66), 1.24 (L vs. S, 95% CI: 1.04–1.49), and 2.87 (10 vs. 12, 95% CI: 1.38–5.97), respectively. These significant differences were determined in both dominant and recessive models. Of the 5-HTR2A 1438G/A gene polymorphism, the AA genotype increased the OSAS risk, with an OR of 4.21 (95% CI: 2.83–6.25) in a recessive model in male OSAS patients, but no significant association was found in females.

Conclusions

Our meta-analysis demonstrated that polymorphisms in the 5-HTR2A 1438G/A and 5-HTT genes contributed to susceptibility to OSAS. The A allele of the 1438G/A gene polymorphism is predominantly distributed in males and increased the OSAS risk significantly.

Evaluation of cochlear implantation in children with inner ear malformation

OBJECTIVE

This study aimed to compare the outcomes of cochlear implantation (CI) in children with malformed versus normal inner ear anatomy.

METHODS

We assessed 63 children with prelingual deafness, including 12 with inner ear malformations. All had undergone CI before the age of 5 y. We evaluated Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) scores before surgery and at 6, 12, and 24 months after surgery.

RESULTS

In both groups, the CAP and SIR scores increased with time after implantation in follow-up assessments. No significant differences were found in the CAP or SIR scores between the two groups at any of the four follow-up assessments.

CONCLUSION

Children with inner ear malformation can benefit from CI. Although additional factors may influence the outcome of CI in children with inner ear malformations compared to children with deafness from other causes, early implantation may provide similar results.

Ribbon synapse plasticity in the cochleae of Guinea pigs after noise-induced silent damage

Noise exposure at low levels or low doses can damage hair cell afferent ribbon synapses without causing permanent threshold shifts. In contrast to reports in the mouse cochleae, initial damage to ribbon synapses in the cochleae of guinea pigs is largely repairable. In the present study, we further investigated the repair process in ribbon synapses in guinea pigs after similar noise exposure. In the control samples, a small portion of afferent synapses lacked synaptic ribbons, suggesting the co-existence of conventional no-ribbon and ribbon synapses. The loss and recovery of hair cell ribbons and post-synaptic densities (PSDs) occurred in parallel, but the recovery was not complete, resulting in a permanent loss of less than 10% synapses. During the repair process, ribbons were temporally separated from the PSDs. A plastic interaction between ribbons and postsynaptic terminals may be involved in the reestablishment of synaptic contact between ribbons and PSDs, as shown by location changes in both structures. Synapse repair was associated with a breakdown in temporal processing, as reflected by poorer responses in the compound action potential (CAP) of auditory nerves to time-stress signals. Thus, deterioration in temporal processing originated from the cochlea. This deterioration developed with the recovery in hearing threshold and ribbon synapse counts, suggesting that the repaired synapses had deficits in temporal processing.

[Reconstruction of external nose defect with local flaps]

OBJECTIVE

The role of different local flaps in small external nasal skin defect reconstruction was discussed.

METHOD

Forty-two cases of the small size nasal defects (diameter < 2 cm) were repaired with local external nose flap (includes the dorsal nasal flap, nasolabial flap and bilobed flap). The clinical and follow-up data were analyzed of patients with small external nasal skin defects, who accepted different local flaps reconstruction. Dorsal nasal flap, nasolabial flaps (includes island flap, slid flap and axial flap) and bilobed flap were tailored to reconstruct different external nasal defect. Twenty-seven patients were male and fifteen patients were female, the patients' age ranged from 28 to 74 years, the median age was 61 years. Thirty-eight cases resulted from resection of skin malignant tumor and four cases were benign lesions. The diameter of defects was 1-2 cm. The defects were reconstructed by single-stage dorsal nasal flap in 7 cases. There were 30 cases of caudolateral nasal defects were reconstructed by nasolabial flap, single-stage island nasolabial flap in 7 cases, axial flap in 18 cases and slid flap in 5 cases. Superior lateral defects were reconstructed by single-stage bilobed flap in 5 cases.

RESULT

All defects were repaired successfully. All tissue flaps survived and had not necrosis. There was no tumor recurrence during 3 months to 2 years follow-up.

CONCLUSION

The dorsal nasal flap, nasolabial flap and bilobed flap can be used safely and effectively to repair the small external nasal defect and have satisfactory curative effect.

Suppression of outward K⁺ currents by WIN55212-2 in rat retinal ganglion cells is independent of CB1/CB2 receptors

Cannabinoid CB1 receptor (CB1R) signaling system is extensively distributed in the vertebrate retina. Activation of CB1Rs regulates a variety of functions of retinal neurons through modulating different ion channels. In the present work we studied effects of this receptor signaling on K(+) channels in retinal ganglion cells by patch-clamp techniques. The CB1R agonist WIN55212-2 (WIN) suppressed outward K(+) currents in acutely isolated rat retinal ganglion cells in a dose-dependent manner, with an IC50 of 4.7 μM. We further showed that WIN mainly suppressed the tetraethylammonium (TEA)-sensitive K(+) current component. While CB1Rs were expressed in rat retinal ganglion cells, the WIN effect on K(+) currents was not blocked by either AM251/SR141716, specific CB1R antagonists, or AM630, a selective CB2R antagonist. Consistently, cAMP-protein kinase A (PKA) and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) signaling pathways were unlikely involved in the WIN-induced suppression of the K(+) currents because both PKA inhibitors H-89/Rp-cAMP and MAPK/ERK1/2 inhibitor U0126 failed to block the WIN effects. WIN-induced suppression of the K(+) currents was not observed when WIN was intracellularly applied. Furthermore, an endogenous ligand of the cannabinoid receptor anandamide, the specific CB1R agonist ACEA and the selective CB2R agonist CB65 also suppressed the K(+) currents, and the effects were not blocked by AM251/SR141716 or AM630 respectively. All these results suggest that the WIN-induced suppression of the outward K(+) currents in rat retinal ganglion cells, thereby regulating the cell excitability, were not through CB1R/CB2R signaling pathways.

The efficacy of moxifloxacin-based triple therapy in treatment of Helicobacter pylori infection: a systematic review and meta-analysis of randomized clinical trials

Recent evidence shows that moxifloxacin could exert an antimicrobial effect against Helicobacter pylori in both in vitro and in vivo models. To systematically evaluate whether moxifloxacin-containing triple therapy could improve eradication rates and reduce side effects in first-line or second-line anti-H. pylori treatment, eligible articles were identified by searches of electronic databases. We included all randomized trials comparing moxifloxacin-based triple therapy with standard triple or quadruple therapy during H. pylori eradication treatment. Statistical analysis was performed with Review Manager 5.0.10. Subanalysis/sensitivity analysis was also performed. We identified seven randomized trials (n=1263). Pooled H. pylori eradication rates were 79.03% (95%CI: 75.73-82.07) and 68.33% (95%CI: 64.44-72.04) for patients with moxifloxacin-based triple therapy or with standard triple or quadruple therapy, respectively (intention-to-treat analysis). The odds ratio (OR) was 1.82 (95%CI: 1.17-2.81), the occurrence of total side effects was 15.23% (95%CI: 12.58-18.20) and 27.17% (95%CI: 23.64-30.92) for groups with or without moxifloxacin, and the summary OR was 0.45 (95%CI: 0.26-0.77). In subgroup analyses, we noted that the second-line eradication rate in the moxifloxacin group was significantly higher than that in the quadruple therapy group (73.33 vs 60.17%, OR: 1.78, 95%CI: 1.16-2.73, P<0.001). However, there was no difference in first-line eradication treatment. Findings from this meta-analysis suggest that moxifloxacin-based triple therapy is more effective and better tolerated than standard triple or quadruple therapy. Therefore, a moxifloxacin-based triple regimen should be used in the second-line treatment of H. pylori infection.

[Endoscopic reconstruction skull base using pedicled nasoseptal flap and its anatomy measurement]

OBJECTIVE

The harvesting procedures on cadaver heads and a radioanatomic study of measuring dimensions of skull base by endoscopic endonasal approach were performed. The measurements could do help to design the nasoseptal mucoperiosteum and improve the rate of repair success.

METHOD

The surgical procedures were demonstrated on cadaver heads specimens. Then 20 adult CT scans of sinus and skull base were calculated by workstations. The dimensions of three different skull base (the defect of anterior skull base/cribriform plate approach, sellar region/planum sphenoidale region and clivus region) of maximum areas, length and width, were measured. And with these data the nasoseptal flap were designed for providing enough area to cover the defect. The distance from the projection of sphenopalatine foramen to related area of skull base were plused for obtaining desired the length of nasoseptal flap.

RESULT

The mean length from the projection of sphenopalatine to the anterior skull base, planum/sella area and clivus were 49.56 mm, 57.47 and 67.19 mm, respectively. The means of areas of anterior dural defect, transsellar defect and panclivectomy were 16.13 cm2, 14.03 cm2 and 13.12 cm2, respectively. The average length of the nasoseptal flap ranged between 64.71-65.93 mm, the width ranged between 28.57-30.95 mm with an average area of 22.95 cm2.

CONCLUSION

One side of nasal septal flap can provide enough area to reconstruct the anterior skull base and planum/sella area. In some cases, the flap can not completely cover the area of clivus region because of the limitation of its length.

Neuregulin-1 protects against doxorubicin-induced apoptosis in cardiomyocytes through an Akt-dependent pathway

In previous studies, it has been shown that recombinant human neuregulin-1(rhNRG-1) is capable of improving the survival rate in animal models of doxorubicin (DOX)-induced cardiomyopathy; however, the underlying mechanism of this phenomenon remains unknown. In this study, the role of rhNRG-1 in attenuating doxorubicin-induce apoptosis is confirmed. Neonatal rat ventricular myocytes (NRVMs) were subjected to various treatments, in order to both induce apoptosis and determine the effects of rhNRG-1 on the process. Activation of apoptosis was determined by observing increases in the protein levels of classic apoptosis markers (including cleaved caspase-3, cytochrome c, Bcl-2, BAX and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining). The activation of Akt was detected by means of western blot analysis. The study results showed that doxorubicin increased the number of TUNEL positive cells, as well as the protein levels of cleaved caspase-3 and cytochrome c, and reduced the ratio of Bcl-2/Bax. However, all of these effects were markedly antagonized by pretreament with rhNRG-1. It was then further demonstrated that the effects of rhNRG-1 could be blocked by the phosphoinositole-3-kinase inhibitor LY294002, indicating the involvement of the Akt process in mediating the process. RhNRG-1 is a potent inhibitor of doxorubicin-induced apoptosis, which acts through the PI3K-Akt pathway. RhNRG-1 is a novel therapeutic drug which may be effective in preventing further damage from occurring in DOX-induced damaged myocardium.

Comparison of cochlear cell death caused by cisplatin, alone and in combination with furosemide

Establishment of appropriate animal models is an important step in exploring the mechanisms of drug-induced ototoxicity. In the present study, using guinea pigs we compared cochlear lesions induced by cisplatin administered in two regimens: consecutive application alone and in combination with furosemide. The effects of furosemide alone were also evaluated; it was found to cause temporary hearing loss and reversible damage to the stria vascularis. Consecutive application of cisplatin alone appeared to be disadvantageous because it resulted in progressive body weight loss and higher mortality compared to the combined regimen, which used a smaller cisplatin dose. The combined regimen resulted in comparable hearing loss and hair cell loss but a markedly lower mortality. However, their coadministration failed to cause similar damage to spiral ganglion neurons (SGN), as seen in animals that received cisplatin alone. This difference suggests that the combined regimen did not mimic the damage to cochlear neuronal innervation caused by the clinical application of cisplatin. The difference also suggests that the SGN lesion is not caused by cisplatin entering the cochlea via the stria vascularis.

[Design and development of an automatic rotatory chair for canalith repositioning maneuver]

This paper demonstrates a 3D rotatory chair and the development of control rotatory system based on PLC, corresponding software and user interface. The PLC-based three-dimensional rotatory chair has the advantage of maneuverability and stability according to the result of the experiment.

Categories of auditory performance and speech intelligibility ratings of early-implanted children without speech training

OBJECTIVE

To assess whether speech therapy can lead to better results for early cochlear implantation (CI) children.

PATIENTS

A cohort of thirty-four congenitally profoundly deaf children who underwent CI before the age of 18 months at the Sixth Hospital affiliated with Shanghai Jiaotong University from January 2005 to July 2008 were included. Nineteen children received speech therapy in rehabilitation centers (ST), whereas the remaining fifteen cases did not (NST), but were exposed to the real world, as are normal hearing children.

METHODS

All children were assessed before surgery and at 6, 12, and 24 months after surgery with the Categories of Auditory Performance test (CAP) and the Speech Intelligibility Rating (SIR). Each assessment was given by the same therapist who was blind to the situation of the child at each observation interval. CAP and SIR scores of the groups were compared at each time point.

RESULTS

Our study showed that the auditory performance and speech intelligibility of trained children were almost the same as to those of untrained children with early implantation. The CAP and SIR scores of both groups increased with increased time of implant use during the follow-up period, and at each time point, the median scores of the two groups were about equal.

CONCLUSIONS

These results indicate that great communication benefits are achieved by early implantation (<18 months) without routine speech therapy. The results exemplify the importance of enhanced social environments provided by everyday life experience for human brain development and reassure parents considering cochlear implants where speech training is unavailable.

Ototoxicity of cisplatin administered to guinea pigs via the round window membrane

Animal models of ototoxicity represent an elementary tool in otolaryngologic research. Such models are usually created via the consecutive injection of ototoxic drugs or the co-administration of ethacrynic acid and low-dose ototoxic drugs. Injection via the round window membrane (RWM) is one approach that allows for local drug delivery into the inner ear. In this study, 47 guinea pigs received an injection of varying doses of cisplatin via the RWM, and data concerning the animals' auditory brainstem responses, hair cells, and spiral ganglion neurons were analyzed. Our results indicate the high efficiency and generally small reaction of the subjects, suggesting that the application of cisplatin via the RWM is an effective animal model for ototoxicity research.

[Reconstruction of large external nose defect with forehead flap]

OBJECTIVE

To discuss the role of forehead flap in large external nasal defect reconstruction.

METHOD

We retrospectively reviewed the clinical and follow-up data of 11 patients with large or full-thickness external nasal defects, which were reconstructed with single-or two-stage interpolated or island forehead flaps from January 2007 to June 2011. All patients were male,defects of 9 cases were resulted from resection of skin malignant tumor and traumatic defect in 2 cases. The average diameter of defects was 3.3 cm (2.5-5.0 cm). Four cases had alar full thickness defect. The supratrochlear and angular artery of the elders (>70 yrs) and patients with suspicious peripheral blood vessel lesions were scanned before the surgery by Doppler ultrasonic. The defects were reconstructed by two-stage interpolated flap in 7 cases; five cases were reconstructed by single-stage island flap technique. A nasolabial flap based on piriform aperture was turned into the nasal cavity to reconstruct the lining.

RESULT

All defects were repaired successfully. All tissue flap survived and the scar was not conspicuous. One patient had nostril stenosis with mild nasal congestion complain at the 6th postoperative month.

CONCLUSION

The forehead flap, interpolated or island, can be used safely and effectively to repair the large external nasal defect in experienced hands.

Silent damage of noise on cochlear afferent innervation in guinea pigs and the impact on temporal processing

Noise-exposure at levels low enough to avoid a permanent threshold shift has been found to cause a massive, delayed degeneration of spiral ganglion neurons (SGNs) in mouse cochleae. Damage to the afferent innervation was initiated by a loss of synaptic ribbons, which is largely irreversible in mice. A similar delayed loss of SGNs has been found in guinea pig cochleae, but at a reduced level, suggesting a cross-species difference in SGN sensitivity to noise. Ribbon synapse damage occurs “silently” in that it does not affect hearing thresholds as conventionally measured, and the functional consequence of this damage is not clear. In the present study, we further explored the effect of noise on cochlear afferent innervation in guinea pigs by focusing on the dynamic changes in ribbon counts over time, and resultant changes in temporal processing. It was found that (1) contrary to reports in mice, the initial loss of ribbons largely recovered within a month after the noise exposure, although a significant amount of residual damage existed; (2) while the response threshold fully recovered in a month, the temporal processing continued to be deteriorated during this period.

[The role of MR and endoscopy in postoperative management of skull base reconstruction by vascular pedicle septal flap]

OBJECTIVE

To explore the significance of MR and endoscopy in the postoperative management of skull base reconstruction with a vascular pedicle nasoseptal mucoperiosteal flap.

METHOD

The immediate, and delayed postoperative MR imaging scans and endoscopic data of 8 patients who underwent endonasal endoscopic reconstruction of skull base dural defects with a vascular pedicle nasoseptal mucoperiosteal flap were retrospectively studied. Among the 8 patients, 7 cases have integrated immediate, delayed postoperative MR and synchronous endoscopic data which were harvest at the first week and at a 3- to 7-month interval respectively. One case was followed up by CT and endoscopy. The intracranial parenchymal changes, local situation of skull base defect site, the septal flap, healing of flap donor site and the transition of naso sinus mucosa were fully evaluated to explore the healing process and to improve the success rate of the reconstruction.

RESULT

We can obtain the key postoperative information of intracranial and the skull base reconstruction site with MR and endoscopy. The MR can exclude the intracranial complications such as postoperative intracranial hematoma, cerebral edema, or pneumocephalus, and clearly show the location and extent of skull base defects, the position of the flap, the overlapping manner between the dural defect margin and the flap and the postoperative cerebrospinal fistula. In immediate and postoperative follow-up with MR, the septal flap had homogeneous enhanced image with a roughly "C" figure under the skull base, indicating stable blood supplement. The synchronous endoscopic examination also proved the survival of the septal flaps in 7 cases , the cerebrospinal fluid leakage in 1 case. One case flap necrosis. The septal flaps presented edema and congested in the immediate postoperative endoscopy, and returned to normal in the delayed examination. The non-vascular materials such as gelatin sponge and fat tissue had the different characteristics signal. Nasal mucosal edema and sinus ventilation continually recovered during the follow up and the exposed septal cartilage on the donor site resurfaced by mucosa in 2 months.

CONCLUSION

MR and endoscopy could provide the critical postoperative information about the vascular pedicle septal flap reconstruction. MR combined with endoscopy not only could rule out the complications, but also could gain the information such as the position, blood supply and healing of the flap, at the same time detected the cerebrospinal fluid leakage to provide accurate information for the secondary stage reconstruction. The information got from MR and endoscopy were important for the surgeon and the radiologist to recognize the flap and to evaluate for variations that may suggest potential flap failure.

Inner ear gene transfection in neonatal mice using adeno-associated viral vector: a comparison of two approaches

Local gene transfection is a promising technique for the prevention and/or correction of inner ear diseases, particularly those resulting from genetic defects. Adeno-associated virus (AAV) is an ideal viral vector for inner ear gene transfection because of its safety, stability, long-lasting expression, and its high tropism for many different cell types. Recently, a new generation of AAV vectors with a tyrosine mutation (mut-AAV) has demonstrated significant improvement in transfection efficiency. A method for inner ear gene transfection via the intact round window membrane (RWM) has been developed in our laboratory. This method has not been tested in neonatal mice, an important species for the study of inherited hearing loss. Following a preliminary study to optimize the experimental protocol in order to reduce mortality, the present study investigated inner ear gene transfection in mice at postnatal day 7. We compared transfection efficiency, the safety of the scala tympani injection via RWM puncture, and the trans-RWM diffusion following partial digestion with an enzyme technique. The results revealed that approximately 47% of inner hair cells (IHCs) and 17% of outer hair cells (OHCs) were transfected via the trans-RWM approach. Transfection efficiency via RWM puncture (58% and 19% for IHCs and OHCs, respectively) was slightly higher, but the difference was not significant.

[Endonasal endoscopic salvage surgical treatment for local recurrent nasopharyngeal cancer]

Nasopharyngeal cancer is a low differentiated squamous cell carcinoma, and the radiation therapy is the primary choice. It's 5 year survival rate may reach 64.4%, while 10.0% cases may suffer from the local recurrence. The salvage radiation or surgery is still the main choice for recurrent cases now. However the recurrent tumor become radiation insensitive and meanwhile, morbidity and mortality become higher. The experience of open salvage surgery on the recurrent radiation insensitive tumor had been proved safely, and the related morbidity and mortality are acceptable. Recently, the endoscopic salvage surgery has been developed, some preliminary experience has been obtained and the result looks promising. In this article, the pathobiological characteristics of the postradiation local recurrent nasopharyngeal cancer, the anatomy of nasopharyngus and related skull base area, especially the petroclival region and current situation of endonasal endoscopic salvage surgery were reviewed here. Basic principle of oncological surgery that endoscopic surgery should followed and possible endoscopic surgical approaches were proposed.

Leukemia-related chromosomal loss detected in hematopoietic progenitor cells of benzene-exposed workers

Benzene exposure causes acute myeloid leukemia and hematotoxicity, shown as suppression of mature blood and myeloid progenitor cell numbers. As the leukemia-related aneuploidies monosomy 7 and trisomy 8 previously had been detected in the mature peripheral blood cells of exposed workers, we hypothesized that benzene could cause leukemia through the induction of these aneuploidies in hematopoietic stem and progenitor cells. We measured loss and gain of chromosomes 7 and 8 by fluorescence in situ hybridization in interphase colony-forming unit-granulocyte-macrophage (CFU-GM) cells cultured from otherwise healthy benzene-exposed (n=28) and unexposed (n=14) workers. CFU-GM monosomy 7 and 8 levels (but not trisomy) were significantly increased in subjects exposed to benzene overall, compared with levels in the control subjects (P=0.0055 and P=0.0034, respectively). Levels of monosomy 7 and 8 were significantly increased in subjects exposed to <10 p.p.m. (20%, P=0.0419 and 28%, P=0.0056, respectively) and ≥ 10 p.p.m. (48%, P=0.0045 and 32%, 0.0354) benzene, compared with controls, and significant exposure-response trends were detected (P(trend)=0.0033 and 0.0057). These data show that monosomies 7 and 8 are produced in a dose-dependent manner in the blood progenitor cells of workers exposed to benzene, and may be mechanistically relevant biomarkers of early effect for benzene and other leukemogens.

P3-18-05: Triple-Negative Breast Cancer: Stem Cells, Cancer and New Treatment Strategy

Background: Women with triple negative breast cancer (TNBC) have a worse prognosis compared with other breast cancer subtypes. Hormonal or Herceptin-based therapies were found to be ineffective because of the loss of target receptors such as ER, PR and HER-2 amplification. TNBC has increased recurrence and poor survival, despite initial response to neoadjuvant chemotherapy. The aim of this study was to determine whether current drug treatment(s) eliminates bulk of tumor cells, but it has a minimal effect on cancer stem cells (CSCs) leading to tumor recurrence.

Materials and Methods: Cancer stem cells were identified by ALDH-positive population by fluorescence-activated cell sorting. CSCs ability to form mammospheres, are generated in nonadherent and nondifferentiated conditions. Apoptosis was assessed using the Cell Death Detection ELISAPLUS kit. Xenograft tumor formation was evaluated using Nod/Scid mice. Cancer stem cell levels in human TNBC and ER+, PR+ and HER2− tumors were obtained by CD44+/ CD24low/− immunohistochemistry.

Results: TNBC tumors express relatively higher levels of cancer stem cells compared to ER-positive, PR-positive and HER2−negative breast tumors. We studied the effects of PARP inhibitors (AZD2281 and BSI-201), paclitaxel, docetaxel, cisplatin and cisplatin plus TRAIL on CSCs derived from CRL-2335 and MDA-MB-468 TNBC cells in vitro. The in vitro data indicates that cisplatin plus TRIAL treatment was most effective in eliminating CSCs compared to PARP inhibitors, cisplatin, paclitaxel and docetaxel. Treatment with cisplatin plus TRAIL also inhibits Wnt-1 signaling and its downstream target, β-catenin, phospho β-catenin, cyclin D1, increased apoptosis, reduced proliferation and mammosphere formation. Inhibition of Wnt-1 by siRNA significantly reduced the ability of CSCs to form mammospheres compared to control. However, maximum effect was seen in cisplatin plus TRAIL treated cells. The combination of cisplatin/TRAIL also inhibited the growth of CRL-2335 Xenografts. Discussion: We demonstrate for the first time that cisplatin plus TRAIL is highly effective in reducing CSCs compared to PARP inhibitors, docetaxel or paclitaxel in TNBC cells in vitro. Inhibition of Wnt-1 signaling pathways by siRNA or cisplatin plus TRAIL reduces cell proliferation and increases apoptosis in CSCs. Taken together the data suggests that cisplatin plus TRAIL treatment has the potential of providing a new strategy for improving the therapeutic outcome in TNBC patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-18-05.

Immediate Repair Compared with Delayed Repair of Congenital Omphalocele: Short-Term Neonatal Outcomes in China

This prospective study evaluated the short-term outcomes of 16 neonates undergoing single congenital omphalocele repair. Parents made informed choices for their baby to receive either immediate repair (IR group, n = 8) or repair ≥ 3 h after delivery (control group, n = 8). All babies were delivered by elective caesarian section. Babies in the two groups were matched one-to-one according to their birth weight, bulging volume and gestational age. Short-term outcomes included the incidence of infection and the lengths of stay in the neonatal intensive care unit (NICU) and in the hospital. Compared with the control group, the IR group showed a significantly lower incidence of infection, shorter surgical duration, shorter NICU stay, less time on total parenteral nutrition, less time to total enteral nutrition and shorter length of hospital stay. Immediate repair significantly improved the short-term neonatal outcomes of congenital omphalocele in China.

Efficient cochlear gene transfection in guinea-pigs with adeno-associated viral vectors by partial digestion of round window membrane

The auditory portion of the inner ear, the cochlea, is an ideal organ for local gene transfection owing to its relative isolation. Various carriers have been tested for cochlear gene transfection. To date, viral vectors appear to have much higher transfection efficacy than non-viral mechanisms. Among these vectors, recombinant adeno-associated virus (rAAV) vectors have several advantages such as being non-pathogenic and the ability to produce prolonged gene expression in various cell types. However, rAAV vectors cannot pass through the intact round window membrane (RWM), otherwise a very attractive approach to access the human inner ear. In this study, performed in guinea-pigs, we describe a method to increase the permeability of RWM to rAAV vectors by partial digestion with collagenase solution. Elevated delivery of rAAV across the partially digested RWM increased transfection efficacy to a satisfactory level, even though it was still lower than that achieved by direct cochleostomy injection. Functional tests (auditory brainstem responses) showed that this enzymatic manipulation did not cause permanent hearing loss if applied appropriately. Morphological observations suggested that the damage to RWM caused by partial digestion healed within four weeks. Taken together, these findings suggest that partial digestion of the RWM is a safe and effective method for increasing the transfection of cochlear sensory cells with rAAV.

[Surgical management of sinonasal and adjacent skull base benign fibro-osseous lesions]

OBJECTIVE

To explore the use of transnasal endoscopy and open surgical approaches for management of sinonasal and adjacent skull base benign fibro-osseous lesions, the surgical methods, precautions, clinical efficacies were also described.

METHOD

Fifteen patients were reviewed, including osteoma in 6 cases, Ossifying fibroma in 2 cases and fibrous dysplasia in 7 cases. Analyzed the pathological features and CT images, and to select surgical approach according to the location and extent of lesions. Eleven patients were operated through transnasal endoscopic procedure, including 7 cases with ipsilateral nasal approach and 4 cases with extended binasal approach; 4 cases with open surgical approach, including trans-eyebrow approach in 1 case and bicoronal approach in 3 cases.

RESULT

All patients were followed up for 2 months to 4 years, gross resection of lesions in 10 cases but partial resection in 5 cases with fibrous dysplasia. The clinical symptoms and facial deformity in all cases were eliminated or significantly relieved postoperatively. Cerebrospinal fluid leakage occurred in 1 case, was successfully repaired during the endoscopic operation. Preoperative diplopia in 3 cases, 2 cases disappeared after six months, one case was improved significantly. There were no postoperative orbital or intracranial complications.

CONCLUSION

Surgery is an effective means to resect lesions which had obviously clinical symptoms. The location and extent of lesions were the decisive factor to choose an open or endoscopic approach. Endoscopic sinus surgery can manage the midline skull base lesions which extend from the posterior wall of the frontal sinus to the clivus, well the open surgical approach is suitable for lesions locating the area beyond the medial orbital wall. No matter choosing which approach, osteoma, ossifying fibroma can be completely removed. For the fibrous dysplasia, as an extensive but self-limiting lesion, the surgery is performed only for relieving symptoms and facial deformity. So the partial resection is preferred and reasonable other than radical total resection. Even the severe fibrous dysplasia lesions caused the optic canal stenosis but present normal vision, it is unnecessary to perform prophylactic decompression of the optic nerve.