cdh23 affects congenital hearing loss through regulating purine metabolism

Introduction

The pathogenic gene CDH23 plays a pivotal role in tip links, which is indispensable for mechanoelectrical transduction in the hair cells. However, the underlying molecular mechanism and signal regulatory networks that influence deafness is still largely unknown.

Methods

In this study, a congenital deafness family, whole exome sequencing revealed a new mutation in the pathogenic gene CDH23, subsequently; the mutation has been validated using Sanger sequencing method. Then CRISPR/Cas9 technology was employed to knockout zebrafish cdh23 gene. Startle response experiment was used to compare with wide-type, the response to sound stimulation between wide-type and cdh23-/-. To further illustrate the molecular mechanisms underlying congenital deafness, comparative transcriptomic profiling and multiple bioinformatics analyses were performed.

Results

The YO-PRO-1 assay result showed that in cdh23 deficient embryos, the YO-PRO-1 signal in inner ear and lateral line neuromast hair cells were completely lost. Startle response experiment showed that compared with wide-type, the response to sound stimulation decreased significantly in cdh23 mutant larvae. Comparative transcriptomic showed that the candidate genes such as atp1b2b and myof could affect hearing by regulating ATP production and purine metabolism in a synergetic way with cdh23. RT-qPCR results further confirmed the transcriptomics results. Further compensatory experiment showed that ATP treated cdh23-/- embryos can partially recover the mutant phenotype.

Conclusion

In conclusion, our study may shed light on deciphering the principal mechanism and provide a potential therapeutic method for congenital hearing loss under the condition of CDH23 mutation.

Deep Underground Laboratory Measurement of ^{13}C(α,n)^{16}O in the Gamow Windows of the s and i Processes

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

Vestibular function in children with cochlear implant: Impact and evaluation

Over the last 30 years, cochlear implant (CI) has been dedicated to improving the rehabilitation of hearing impairments. However, CI has shown potential detrimental effects on vestibular function. For children, due to atypical symptoms and difficulty in cooperating with vestibular function tests, systematic and objective assessments of vestibular function with CI have been conducted sparsely. This review focuses on the impact of vestibular function in children with CI and summarized the evaluation of vestibular function in children. In addition, some recommended strategies are summarized and proposed.

Cochlear implantation in prelingually deafened patients: Evaluation in hearing, speech ability, and quality of life

OBJECTIVES

The main purpose of cochlear implantation for prelingual deafness is to restore the deaf children's auditory function, obtain normal speech development, learning and social ability, and improve the quality of life. Previous studies mostly focused on the improvement of simple hearing or speech ability. This study aims to evaluate the changes of hearing and speech ability and family life quality of patients after cochlear implantation, and to explore the effect of cochlear implantation on hearing and speech rehabilitation of patients.

METHODS

In February 2021, using the convenient sampling method, 171 patients who have completed cochlear implantation were selected from the database of cochlear implantation follow-up center of a class III Tertiary hospital in Hunan Province. Questionnaires were used to investigate the patients' parents, which were Categories of Auditory Performance (CAP), Speech/Spatial and Qualities of Hearing Scale-Parents' Version (SSQ-P), and Children using Hearing Implants Quality of Life (CuHI-QoL). T-test and analysis of variance were used to explore the postoperative auditory and speech ability of patients at different ages in different periods (<2.5-year group, 2.5-4.5-year group and >4.5-year group), and Pearson correlation analysis was used to explore the correlation. Multiple linear regression was used to explore the relationship between the dimension of patients' quality of life and the scores of scale for evaluating auditory ability (CAP, speech perception, spatial hearing, and other hearing characteristics).

RESULTS

The values of CAP and SSQ-P in the <2.5-year group were lower than those in the 2.5-4.5-year and >4.5-year groups (all P<0.05). Pearson correlation analysis showed that postoperative years and CuHI-QoL scores (parental expectations and patients' quality of life) were positively correlated with score of CAP, SSQ-P and its dimension, respectively (all P<0.05). The results of multiple linear regression analysis showed the CAP scores and speech perception were the influencing factors for the quality of life (R2=0.170, P<0.01).

CONCLUSIONS

Two and a half years after operation is the rapid growth period of patients' hearing and language ability, and the growth rate becomes slow after stabilization. With the extension of postoperative years, the patients' hearing and speech ability becomes stronger, and the quality of life is better.

[An analysis of surgical management of difficulties during cochlear implant with inner ear anomalies]

Objective:The purpose of this study is to review the difficulties that can occur during cochlear implant surgery in patients with inner ear abnormalities and the management. Method:A retrospective analysis was made on 186 cases of cochlear implant with inner ear malformation, the types of inner ear malformations included 6 cases（3.23%） of isolated semicircular dysplasia, 137 cases（73.66%） of isolated large vestibular aqueducts, 26 cases（13.98%） of Mondini malformations, 6 cases（3.23%） of incomplete septal type Ⅲ, 3 cases（1.61%） of internal auditory stenosis, 7 cases（3.76%） of cochlear dysplasia and 1 case（0.54%） of incomplete septal typeⅠ. Two hundred patients with normal inner ear structures were randomly selected as the control group. The data collected included the types of inner ear abnormalities, intraoperative manifestations, clinical management strategies, and postoperative speech rehabilitation, and the literature was reviewed. Result:148 patients（77.49%） with inner ear malformation underwent successful surgery, electrode insertion was incomplete in 6 patients（3.14%）, and cerebrospinal fluid blowout occurred in 29 patients（15.18%）, it was difficult to locate the window because of the abnormal structure of the window in 8 cases（4.19%）. In 191 patients, the facial recess approach was adopted intraoperatively, and 17.8% of the patients had significant structural abnormalities of the facial nerve, significantly more than the group with normal inner ear structure. Only 1 patient showed delayed facial nerve paralysis 1 week after surgery, and recovered well after treatment. 6.81% of the patients adopted the expanded round window approach, which was significantly lower than that of the group with normal inner ear structure（28%）. There was no significant difference between patients with inner ear malformation and patients with extremely severe deafness with normal inner ear structure who received cochlear implant in speech rehabilitation. Conclusion:Cochlear implant is safe, feasible and effective for patients with inner ear malformation. For patients with inner ear malformation, special attention should be paid to the preoperative imaging reading to predict the possible risks during the operation. The safest surgical plan, including the type of electrode and the manner in which the window is opened, must be prepared before the operation, and the operation must be performed or directed by an experienced surgeon who can adjust the optimal surgical plan according to what is seen during the operation.

[Clavien-Dindo classification of complications after complete mesocolic excision in laparoscopic radical resection of right hemicolon cancer and analysis on its influencing factors]

Objective: To investigate the Clavien-Dindo (CD) classification of complications after complete mesocolic excision (CME) in laparoscopic radical resection of right-sided hemicolon cancer and its influencing factors. Methods: A retrospective case-control study was performed. Inclusion criteria: (1) the adenocarcinoma located at colon from cecum to hepatic flexure; (2) laparoscopic right hemicolectomy with CME was completed. Exclusion criteria: (1) patients had severe organ dysfunction before operation; (2) tumor invaded adjacent organs or developed distant organ metastasis; (3) emergency surgery; (4) failure of laparoscopic surgery, and conversion to laparotomy; (5) without complete clinical data. Finally, clinical data of 141 patients in our hospital form March 2015 to February 2019 were retrospectively analyzed. CD grading standard was used to evaluate postoperative complications. Univariate and multivariate logistic regression analyse were used to analyze the factors that might affect the complications. Survival analysis was conducted by grouping the indicators with statistically significant difference in multivariate analysis. Kaplan-Meier method was used to draw the survival curve and log-rank test was used to analyze the difference. Results: Of the 141 patients, 89 were male and 52 were female with mean age of (61.8±11.0) years. All the operations completed successfully. A total of 37 postoperative complications were developed in 26 (18.4%) patients had postoperative 37 cases of complications, mainly including 7 delayed incision healing, 6 diarrhea, and 5 respiratory dysfunction. According to CD classification standard, grade I, II, and IV a complication rates were 40.5% (15/37), 56.8% (21/37), and 2.7% (1/37) respectively. Univariate analysis showed that age ≥ 65 years (χ(2)=4.338, P=0.037), BMI ≥ 28 kg/m(2) (χ(2)=5.971, P=0.015), and preoperative hemoglobin < 100 g/L (χ(2)=3.985, P=0.046) were risk factors of postoperative complications. Multivariate analysis testified that age ≥ 65 years (OR=7.991, 95%CI: 2.203 to 28.983, P=0.002) and body mass index (BMI) ≥ 28 kg/m(2) (OR=4.231, 95%CI: 1.034 to 17.322, P=0.045) were independent risk factors for complications after laparoscopic CME surgery for right-sided hemicolon cancer. All the patients were followed up for median time of 24 (1-48) months. The log-rank test showed that there were no significant differences in the cumulative survival rate between patients of age < 65 years and age ≥ 65 years (χ(2)=0.986, P=0.321), and between those with BMI < 28 kg/m(2) and BMI ≥ 28 kg/m(2) (χ(2)=0.370, P=0.543). Conclusions: The main complications after CME in laparoscopic radical resection of right hemicolon cancer are CD grade I and II. Elderly and obesity are independent risk factor for postoperative complications. Before the operation, reasonable preventive measures should be taken for the elderly and the obese in order to reduce postoperative complications.

[Primary Ewing's sarcoma of the temporal bone: a rare case]

SummaryEwing's sarcoma is a malignant, round cell tumor arising from the bones and primarily affecting children and adolescent. Involvement of the skull bones is rarely reported, constituting 1%-6% of the total Ewing's sarcoma cases. We describe a 33 years old male patient having Ewing sarcoma of the mastoid and petrous parts of temporal bone, whose clinical presentation mimicked mastoiditis with facial nerve palsy. We discuss the clinical and therapeutic course of an extensive primary Ewing sarcoma of the temporal bone and review this entity's literature in detail. The etiopathology of an acute peripheral facial palsy is often hard to identify. If the facial weakness starts together with symptoms suggesting an inflammatory process, the differential diagnosis may be focused first on diseases like herpes zoster oticus and a severe course of acute purulent otitis media. As an uncommon tumor of the temporal bone, physicians should consider Ewing's sarcoma in the differential diagnosis of children and adolescents who present with facial nerve paralysis. And in the case of ambiguous clinical findings, a surgical exposure of the middle ear is recommended.

Orbital-Selective Kondo Entanglement and Antiferromagnetic Order in USb_{2}

In heavy-fermion compounds, the dual character of f electrons underlies their rich and often exotic properties like fragile heavy quasiparticles, a variety of magnetic orders and unconventional superconductivity. 5f-electron actinide materials provide a rich setting to elucidate the larger and outstanding issue of the competition between magnetic order and Kondo entanglement and, more generally, the interplay among different channels of interactions in correlated electron systems. Here, by using angle-resolved photoemission spectroscopy, we present the detailed electronic structure of USb_{2} and observe two different kinds of nearly flat bands in the antiferromagnetic state of USb_{2}. Polarization-dependent measurements show that these electronic states are derived from 5f orbitals with different characters; in addition, further temperature-dependent measurements reveal that one of them is driven by the Kondo correlations between the 5f electrons and conduction electrons, while the other reflects the dominant role of the magnetic order. Our results on the low-energy electronic excitations of USb_{2} implicate orbital selectivity as an important new ingredient for the competition between Kondo correlations and magnetic order and, by extension, in the rich landscape of quantum phases for strongly correlated f electron systems.

Efficient introduction of an isogenic homozygous mutation to induced pluripotent stem cells from a hereditary hearing loss family using CRISPR/Cas9 and single-stranded donor oligonucleotides

BACKGROUND

Heterozygous purinergic receptor p2x gene ( P2RX2) c.178G>T (p.V60L) mutations can lead to progressive hearing loss (HL) and increased susceptibility to noise. However, the underlying mechanisms remain unclear. A combination of human induced pluripotent stem cell (hiPSC) technology with clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein (Cas)9-mediated gene editing may provide a promising tool to study gene function and treat hereditary deafness in humans.

METHODS

hiPSC technology and CRISPR/Cas9-mediated gene editing were used to generate heterozygous and homozygous P2RX2 c.178G>T (p.V60L) cell models.

RESULTS

We generated non-integrative hiPSCs from urine samples derived from three members of a large Chinese family carrying heterozygous P2RX2 c.178G>T mutations (designated P2RX2+/-) as a model to study P2RX2-mediated hereditary HL. Furthermore, we used CRISPR/Cas9 and single-stranded donor oligonucleotides to genetically establish homozygous P2RX2 c.178G>T hiPSCs (designated P2RX2-/-) from heterozygous patient-specific hiPSCs as a control to further study the pathological gene function.

CONCLUSIONS

Heterozygous and homozygous P2RX2-mutated hiPSC lines are good models to investigate the pathological mechanisms of P2RX2 mutations in HL pathogenesis. Our findings confirmed our hypothesis that it is feasible and convenient to introduce precise point mutations into genomic loci of interest to generate gene-mutated hiPSC models.

[The expression of P19ink4d in the pathogenesis and development of hearing loss]

Objective: This study aimed to investigate the P19ink4d expression in cochlea of mice model with noise induced hearing loss and the role of P19ink4d in the degeneration of inner ear cells. It also searched for P19ink4d gene alterations in patients with profound sensorineural deafness.Method: CBA/J mice were exposed to broad band noise at 101 dB SPL for 2 hours, auditory brainstem response (ABR) were examined to confirm noise lead to the permanent threshold shift. Immunohistochemical staining, Western blotting, and real-time polymerase chain reaction (PCR) were performed on cochlear tissues, to elucidate changes in P19ink4d expression in mice after noise exposure. For clinical evaluation, 400 children from unrelated families with severe or profound sensorineural hearing loss (SNHL) were recruited, genomic DNA was obtained from the patients and was subjected to DNA microarray to screen mutations in 4 most common genes. The sample that carried none of the common mutant alleles were subjected to PCR and sequenced to detect mutations in P19ink4d gene.Result: The ABR threshold shift of mice in the experimental group significantly increased after noise exposure and was higher than that in the null-noise group. The ABR of 1 day post noise was least among experimental groups and there is no statistical different between ABR of 7 days and 14 days post noise. The missing of outer hair cells occurred after noise exposure, while the inner hair cells hardly miss. It was found that the P19ink4d expression increased significantly in the inner ear cells 3 hours after noise exposure, then recovered in 24 hours. Western blot indicated that the amount of P19ink4d increased transitorily 3-6 h after the noise. However, no mutation existed within the coding exons of P19ink4d in the patients with profound sensorineural deafness.Conclusion: The results support the concept that P19ink4d may play an important role in the pathogenesis and development of noise induced hearing loss.

Anti-neutrophil cytoplasmic antibody-associated hypertrophic cranial pachymeningitis and otitis media: a review of literature

Background and objective

It has been recognized that anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides may lead to hypertrophic pachymeningitis (HP) or intractable otitis media (OM). To our knowledge, few cases of coexistent ANCA-related HP and OM have been described previously. To increase awareness of this disease, we reviewed the literature describing patients with HP and intractable OM in a population with AAV to guide clinical decision making for otolaryngologists.

Methods

 PubMed was searched with the following terms: ANCA-associated vasculitis, otitis media, and hypertrophic pachymeningitis. Only patients with concomitant AAV, OM and HP were considered and included in this review.

Results

A total of 243 articles were reviewed, and of these, 6 met inclusion criteria. Headache, cranial polyneuropathy, and intractable OM with effusion or granulation were common. Serum MPO–ANCA positivity was most common in Asian patients. Almost all patients had dural mater thickening on gadolinium-enhanced magnetic resonance imaging of the brain. Corticosteroids plus an immunosuppressant was more effective and most patients had improved hearing after treatment, but approximately 50% of subjects had disease relapse.

Conclusion

In this review, we summarized the current knowledge on the clinical features, diagnosis, treatment, and pathogenesis of this disease. We should carefully detect the potential cases of ANCA-related HP and OM in patients with intractable OM, HP, or AAV, and make the optimal treatment plan to avoid long-term neurological complications and irreversible hearing loss. Furthermore, due to an increased possibility of relapse, close follow-up, including a hearing test, ANCA titers, imaging examination, and detection of toxic and side effects of immunosuppressive therapy, are necessary.

Role of Hsp90/Akt pathway in the pathogenesis of gentamicin-induced hearing loss

Studies have suggested that gentamicin may induce hair cell apoptosis through the Hsp90/Akt signaling pathway. Nevertheless, the exact mechanisms remain unclear. The following study investigated Hsp90 expression in gentamicin-treated cochleae (in vitro and in vivo) and explored whether the Hsp90/Akt signaling pathway has a role in gentamicin ototoxicity. For in vitro experiments, organotypic cultures from post-natal organ of Corti, collected from post-natal day 2 or 3 (p2-3) CBA/J explants were treated with 0.2 mM gentamicin for 24 h; for the in vivo experiments, 6-week-old male CBA/J mice were injected with gentamicin (150 mg/kg) to induce hearing loss. P-Akt and AKT proteins expression and the levels of Hsp90-Akt complex were examined using immunochemistry and western blot. Our data suggested that Hsp90 expression decreased in the hair ear cells after treatment. In addition, the pAkt and Hsp90/AKT levels significantly decreased in treated mice compared to the control group. To conclude, these results support the idea that the Hsp90/Akt signaling pathway may have an important role in the ototoxic effects of gentamicin.

[Analysis of the application and funding projects of National Natural Science Foundation of China in the field of burns and plastic surgery from 2010 to 2016]

We analyzed the data of application and funding projects of the National Natural Science Foundation of China (NSFC) during 2010-2016 in the field of burns and plastic surgery and summarized the NSFC funding pattern, the research hotspots, and weaknesses in this field. The NSFC has funded 460 projects in the field of burns and plastic surgery, with total funding of RMB 227.96 million. The scientific issues involved in the funding projects include orthotherapy against malformations, wound repair, basic research of burns, skin grafting, scars prevention, and regeneration of hair follicle and sweat glands. The research techniques involved in the funding projects are diversified. NSFC plays an important role in the scientific research and talents training in the field of burns and plastic surgery.

[Clinical possibility of low ligation of inferior mesenteric artery and lymph nodes dissection in laparoscopic low anterior resection]

OBJECTIVE

To investigate the clinical possibility of low ligation of inferior mesenteric artery (IMA) and lymph nodes dissection in laparoscopic low anterior resection.

METHODS

Data was collected retrospectively from 216 patients who underwent laparoscopic low anterior resection in our hospital from June 2011 to January 2015.Patients were divided into control group (132 cases) and observation group (84 cases). The observation group was treated with low ligation of IMA and lymph nodes dissection, and the control group was cured by high ligation of IMA and lymph nodes dissection. We analyzed the operation time, the number of lymph nodes dissection, the number of lymph nodes removed around the root of IMA, the rate of lymph node metastasis around the root of IMA, the incidence of anastomotic leakage and the ventilation time after the operation.

RESULTS

There was no significant difference between the two group in the pre-operative data, operation time, the number of lymph nodes dissection the number of lymph nodes removed around the root of IMA, the rate of lymph node metastasis around the root of IMA and the incidence of anastomotic leakage (P>0.05). The observation group were significantly better than the control group the in the ventilation time after the operation (P<0.05). The follow up time was 12 to 67 months. The median follow up time was 37 months. One patient in observation group died of cardiovascular disease. One patient in control group died of metastatic carcinoma.

CONCLUSION

Detection of low ligation of inferior mesenteric artery and lymph nodes dissection in laparoscopic low anterior resection is safe and practicable, which should be widely applied.

Intelligence development of pre-lingual deaf children with unilateral cochlear implantation

OBJECTIVE

The present study aims to test whether deaf children with unilateral cochlear implantation (CI) have higher intelligence quotients (IQ). We also try to find out the predictive factors of intelligence development in deaf children with CI.

METHODS

Totally, 186 children were enrolled into this study. They were divided into 3 groups: CI group (N = 66), hearing loss group (N = 54) and normal hearing group (N = 66). All children took the Hiskey-Nebraska Test of Learning Aptitude to assess the IQ. After that, we used Deafness gene chip, Categories of Auditory Performance (CAP) and Speech Intelligibility Rating (SIR) methods to evaluate the genotype, auditory and speech performance, respectively.

RESULTS

At baseline, the average IQ of hearing loss group (HL), CI group, normal hearing (NH) group were 98.3 ± 9.23, 100.03 ± 12.13 and 109.89 ± 10.56, while NH group scored higher significantly than HL and CI groups (p < 0.05). After 12 months, the average IQ of HL group, CI group, NH group were99.54 ± 9.38,111.85 ± 15.38, and 112.08 ± 8.51, respectively. No significant difference between the IQ of the CI and NH groups was found (p > 0.05). The growth of SIR was positive correlated with the growth of IQ (r = 0.247, p = 0.046), while no significant correlation were found between IQ growth and other possible factors, i.e. gender, age of CI, use of hearing aid, genotype, implant device type, inner ear malformation and CAP growth (p > 0.05).

CONCLUSIONS

Our study suggests that CI potentially improves the intelligence development in deaf children. Speech performance growth is significantly correlated with IQ growth of CI children. Deaf children accepted CI before 6 years can achieve a satisfying and undifferentiated short-term (12 months) development of intelligence.

[Combination measurement of liver and spleen stiffness with portal vein width to evaluate risk of bleeding in esophageal and gastric varices patients]

OBJECTIVE

To evaluate the utility of combined liver stiffness measurement (LSM) and spleen stiffness measurement (SSM), by transient elastography, along with measurement of portal vein width (PVW) for evaluating risk of bleeding in patients with esophageal and gastric varices (EV).

METHODS

A total of 73 patients with cirrhosis who were treated in the Department of Gastroenterology of the Second Affiliated Hospital of Xi'an Jiaotong University between April 2014 and March 2015 were included in the study. Child-Pugh classifications were obtained, portal vein widths were measured by ultrasound, liver and spleen stiffness were measured by transient elastography using FibroTouch®. Patients were examined by electronic endoscopy, upper abdominal computed tomography and standard serum testing. The serum indexes of fibrosis (aspartate aminotransferase (AST) to platelet ratio index (APRI), and AST to alanine aminotransferase ratio (AAR)) were calculated. Patients were grouped according to the results of gastroscopy, with severe (EV) and high risk of bleeding comprising group A and no or mild-to-moderate EV and low risk of bleeding comprising group B. Statistical analysis was carried out with t-test for continuous variables and χ(2) test for categorical variables to first screen out variables different between groups then the correlation with severe EV was assessed by generating receiver operating characteristic (ROC) curves. Lastly, binary logistic regression was used to evaluate the performance of combined variables for diagnosing severe EV and their predictive value for risk of bleeding.

RESULTS

Group A and B showed significant differences for LSM, SSM and PVW (all P < 0.05). The cutoff values for diagnosing severe EV were 23.4 kPa for LSM, 40.3 kPa for SSM and 11.5 mm for PVW, with areas under the ROC curve (AUROC) as 0.655, 0.788 and 0.709 respectively. For combined measurements, the AUROC was 0.773 for LSM plus PVW and 0.840 for LSM plus PVW (with highest diagnostic performance).

CONCLUSIONS

Combination of SSM plus PVW measurement shows high diagnostic performance for evaluating severe EV, and better performance than LSM plus SSM plus PVW and LSM plus PVW, with good predictive value for risk of EV bleeding.

DAPT mediates atoh1 expression to induce hair cell-like cells

Hearing loss is currently an incurable degenerative disease characterized by a paucity of hair cells (HCs), which cannot be spontaneously replaced in mammals. Recent technological advancements in gene therapy and local drug delivery have shed new light for hearing loss. Atoh1, also known as Math1, Hath1, and Cath1, is a proneural basic helix-loop-helix (bHLH) transcription factor that is essential for HC differentiation. At various stages in development, Atoh1 activity is sufficient to drive HC differentiation in the cochlea. Thus, Atoh1 related gene therapy is the most promising option for HC induction. DAPT, an inhibitor of Notch signaling, enhances the expression of Atoh1 indirectly, which in turn promotes the induction of a HC fate. Here, we show that DAPT cooperates with Atoh1 to synergistically promote HC fate in ependymal cells in vitro and promote hair cell regeneration in the cultured basilar membrane (BM) which mimics the microenvironment in vivo. Taken together, our findings demonstrated that DAPT is sufficient to induce HC-like cells via enhancing of the expression of Atoh1 to inhibit the progression of HC apoptosis and to induce new HC formation.

BMP4: a Possible Key Factor in Differentiation of Auditory Neuron-Like Cells from Bone-Derived Mesenchymal Stromal Cells

BACKGROUND

Previous studies have shown that BMP4 may play an important part in the development of auditory neurons (ANs), which are degenerated in sensorineural hearing loss. However, whether BMP4 can promote sensory fate specification from mesenchymal stromal cells (MSCs) is unknown so far.

METHODS

MSCs isolated from Sprague-Dawley (SD) rats were confirmed by expression of MSC markers using flow cytometry and adipogenesis/osteogenesis using differentiation assays. MSCs treated with a complex of neurotrophic factors (BMP4 group and non-BMP4 group) were induced into auditory neuron-like cells, then the differences between the two groups were analyzed in morphological observation, cell growth curve, qRT-PCR, and immunofluorescence.

RESULTS

Flow cytometric analysis showed that the isolated cells expressed typical MSC surface markers. After adipogenic and osteogenic induction, the cells were stained by oil red O and Alizarin Red. The neuronal induced cells were in the growth plateau and had special forms of neurons. In the presence of BMP4, the inner ear genes NF-M, Neurog1, GluR4, NeuroD, Calretinin, NeuN, Tau, and GATA3 were up-regulated in MSCs.

CONCLUSIONS

MSCs have the capacity to differentiate into auditory neuron-like cells in vitro. As an effective inducer, BMP4 may play a key role in transdifferentiation.

The role of transcription factors of neurosensory cells in non-syndromic sensorineural hearing loss with or without inner ear malformation

CONCLUSIONS

Previous studies have stated the roles and correlation of the four TFs (Sox2, Atoh1, Neurog1, and Neurod1) in the development of neurosensory cells. but whether they are inherited pathogenic factors to cause non-syndromic sensorineural hearing loss is unknown so far. This is the first time for screening the Sox2, Atoh1, Neurog1, and Neurod1 genes in children with NSHL. The c.133A > G in Neurod1 gene is a polymorphism, which is not associated with NSHL. Although these genes are the recognized TFs for modulating the development and transformation of NSCs, they may not be the inherited pathogenic factors to cause congenital severe or profound NSHL directly.

OBJECTIVE

To investigate the effect of the transcription factors (TFs) for the development of neurosensory cells (NSCs) and to explore the genetic etiology of congenital profound non-syndromic sensorineural hearing loss (NSHL).

METHODS

Children with NSHL, from multi-national and regional group, and control group were recruited to screen for the most common mutations for non-syndromic deafness among East Asian (mtDNA 12S rRNA: 1555A > G, 1494C > T; SLC26A4: IVS7-2 A > G, 2168 C > T). And mutational analysis of the coding regions in Sox2, Atoh1 and Neurog1, Neurod1 genes were performed.

RESULTS

Only the c.133A > G (p. Ala45Thr) in the Neurod1 gene was detected in this study. The allele frequencies of this variant were 88.00% and 84.88% in the inner ear malformation group and the normal inner ear group, respectively, while 90.85% of children in the control group carried c.133A > G. This variant existed in every group commonly and had no significant difference among them. No variant in the other two TFs was detected in this cohort.

Role of p19ink4d in the pathogenesis of hearing loss

This study aimed to investigate the p19 expression in cisplatin-treated rats and the role of p19 in the degeneration of inner ear cells. It also searched for p19 gene alterations in patients with profound sensorineural deafness. P19ink4d is essential for the postmitotic maintenance of hair cells. It is presumed that a mutation in the functional homolog of p19 or a disturbance in its regulated expression can be the underlying cause of hearing loss. Experiments were conducted on male and female Sprague-Dawley rats (aged 6-7 weeks, 280-320 g) with thresholds of auditory brainstem responses <30 dB in the sound pressure level, and signs of middle ear infection were used for the experiment. For clinical evaluation, 400 children (age less than 13 years) from unrelated families with severe or profound sensorineural hearing loss (SNHL) were recruited at the second Xiangya Hospital of Central South University between 2005 and 2013, and genomic DNA for deafness gene analysis was obtained from peripheral blood samples of the patients and their lineal relatives. It was found that the p19 expression increased over time in the inner ear cells after cisplatin administration, but the p19 mRNA and protein levels significantly decreased in rats with manifested hearing loss induced by cisplatin. However, no mutation existed within the coding exons of p19 in the patients with profound sensorineural deafness. To conclude, the results support the concept that p19 may play an important role in the ototoxic effects of cisplatin and is probably involved in the pathogenesis of hearing loss.

Prevalence of mutations in GJB2, SLC26A4, and mtDNA in children with severe or profound sensorineural hearing loss in southwestern China

AIM

To study the distribution characteristics of common mutations in the GJB2, SLC26A4, and mtDNA genes in children with severe or profound sensorineural hearing loss (SNHL) in southwestern China.

MATERIALS AND METHODS

A total of 1,164 individuals were recruited to screen for the common GJB2, SLC26A4, and mtDNA mutations by microarrays. Subsequencing for the coding region of the GJB2 gene in the samples without the GJB2 hotspot mutations as well as subsequencing for the exon 1 of the TRMU gene in those samples with the mtDNA hotspot mutations was performed by Sanger sequencing. All mutations were analyzed in association with medical imaging.

RESULTS

In this study, 28.43% of all subjects carried mutations. The mutation frequencies in the GJB2, SLC26A4, and mtDNA genes were 17.27%, 7.04%, and 4.12%, respectively. No TRMU mutation was found in the study. The frequency of the mtDNA mutations in the multiethnic minorities was six times that in the Han (11.23% vs. 1.91%; p approaches 0.000) and in the urban group was one-third of that in the suburban group(1.49% vs. 4.47%; p=0.047). The frequency of the GJB2 mutations in urban and suburban groups was 23.38% and 15.99%, respectively (p=0.012). The enlarged vestibular aqueduct (EVA) was the most common inner ear malformation and ∼79.10% of EVA cases were associated with the SLC26A4 mutations.

CONCLUSIONS

More than one-fourth of children with severe or profound SNHL carried the common deafness mutations. The proportions of ethnic minorities and urban subjects could impact the frequency of the GJB2 and mtDNA mutations. The SLC26A4 hotspot mutations are prevalent and correlate strongly with EVA.

The application of genome editing in studying hearing loss

Targeted genome editing mediated by clustered, regularly interspaced, short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9) technology has emerged as one of the most powerful tools to study gene functions, and with potential to treat genetic disorders. Hearing loss is one of the most common sensory disorders, affecting approximately 1 in 500 newborns with no treatment. Mutations of inner ear genes contribute to the largest portion of genetic deafness. The simplicity and robustness of CRISPR/Cas9-directed genome editing in human cells and model organisms such as zebrafish, mice and primates make it a promising technology in hearing research. With CRISPR/Cas9 technology, functions of inner ear genes can be studied efficiently by the disruption of normal gene alleles through non-homologous-end-joining (NHEJ) mechanism. For genetic hearing loss, CRISPR/Cas9 has potential to repair gene mutations by homology-directed-repair (HDR) or to disrupt dominant mutations by NHEJ, which could restore hearing. Our recent work has shown CRISPR/Cas9-mediated genome editing can be efficiently performed in the mammalian inner ear in vivo. Thus, application of CRISPR/Cas9 in hearing research will open up new avenues for understanding the pathology of genetic hearing loss and provide new routes in the development of treatment to restore hearing. In this review, we describe major methodologies currently used for genome editing. We will highlight applications of these technologies in studies of genetic disorders and discuss issues pertaining to applications of CRISPR/Cas9 in auditory systems implicated in genetic hearing loss.

The utility of MRI for pre-operative T and N staging of gastric carcinoma: a systematic review and meta-analysis

OBJECTIVE

To perform a meta-analysis and literature review regarding the diagnostic accuracy of MRI for pre-operative tumour depth invasion (T) and regional lymph node invasion (N) staging of gastric carcinoma (GC).

METHODS

Articles were identified through systematic search of Medline, PubMed, Cochrane Library, Web of Science, Springerlink and several Chinese databases. The study quality was assessed by the quality assessment for studies of diagnostic accuracy. 2 reviewers independently extracted and assessed the data from 11 eligible studies. A meta-analysis was then carried out. Subgroup and sensitivity analyses were also performed.

RESULTS

11 studies (439 patients) were finally included in the current review. Among these studies, the significant evidence of heterogeneity was only discovered for specificity in T4 stage (I(2) = 59.8%). Pooled sensitivity and specificity of MRI to diagnose T stage tumour (T3-4 vs T1-2) were 0.93 [95% confidence interval (CI), 0.89-0.96] and 0.91 (95% CI, 0.87-0.95), respectively. Pooled estimates of sensitivity and specificity of MRI to diagnose N stage tumour (N0 vs N+) were 0.86 (95% CI, 0.80-0.92) and 0.67 (95% CI, 0.54-0.79), respectively. Subgroup analyses showed that diffusion-weighted imaging was more helpful for T staging.

CONCLUSION

The present systematic review suggests that MRI has a good diagnostic accuracy for pre-operative T staging of GC and should be widely used in clinical work. However, the ability for N staging is relatively poor on MRI.

ADVANCES IN KNOWLEDGE

In the pre-operative staging of GC, MRI was a useful tool and may enhance accuracy for the T staging of advanced GC.

A rare disorder mimics otitis media: Langerhans cell histiocytosis of the temporal bone in a child with interstitial pulmonary fibrosis

Langerhans cell histiocytosis (LCH) is a rare disease ranging from a benign to a rapidly fatal condition affecting young children predominantly, and is characterized by an abnormal clonal proliferation of Langerhans cells. We report a case of a 3-year-old child presenting with a 1-year history of otorrhea and otorrhagia followed by a 6-month history of postauricular swelling in the right ear. Imaging demonstrated a large mass of organized tissue. A biopsy was conducted, and the diagnosis of LCH was confirmed by histopathological and immunohistochemical examination. The child was treated with a 12-month course of vinblastine chemotherapy with prednisolone. No clinical evidence of recurrence was noticed after 3 years of follow-up. This rare case highlights the importance for otolaryngologists to keep LCH in mind for differential diagnosis in very young patients with symptoms and signs suggestive of acute mastoiditis or chronic otitis media.

Whole-exome sequencing to decipher the genetic heterogeneity of hearing loss in a Chinese family with deaf by deaf mating

Inherited deafness has been shown to have high genetic heterogeneity. For many decades, linkage analysis and candidate gene approaches have been the main tools to elucidate the genetics of hearing loss. However, this associated study design is costly, time-consuming, and unsuitable for small families. This is mainly due to the inadequate numbers of available affected individuals, locus heterogeneity, and assortative mating. Exome sequencing has now become technically feasible and a cost-effective method for detection of disease variants underlying Mendelian disorders due to the recent advances in next-generation sequencing (NGS) technologies. In the present study, we have combined both the Deafness Gene Mutation Detection Array and exome sequencing to identify deafness causative variants in a large Chinese composite family with deaf by deaf mating. The simultaneous screening of the 9 common deafness mutations using the allele-specific PCR based universal array, resulted in the identification of the 1555A>G in the mitochondrial DNA (mtDNA) 12S rRNA in affected individuals in one branch of the family. We then subjected the mutation-negative cases to exome sequencing and identified novel causative variants in the MYH14 and WFS1 genes. This report confirms the effective use of a NGS technique to detect pathogenic mutations in affected individuals who were not candidates for classical genetic studies.

[Mutation screening in taperin gene in Chinese with prelingual nonsyndromic hearing impairment]

OBJECTIVE

To screen and identify the frequency and characteristic of mutation in stereocilium-related gene Taperin of Chinese prelingual nonsyndromic hearing impairment with DNA microarray combined with PCR.

METHOD

One hundred and thirty-four patients of prelingual nonsyndromic deafness and one hundred health individuals in China were investigated in this study. Genomic DNA was extracted from the patients and was subjected to DNA microarray to screen mutations in 4 most common genes. The samples that carried none of the common mutant alleles were subjected to PCR and sequenced to detect mutations in Taperin gene.

RESULT

Ninteen out of one hundred and thirty-four patients of prelingual nonsyndromic deafness were detected carring common deafness gene with DNA microarray. Taperin gene were detected in one hundred and fifteen patients with PCR. A187S was detected in Taperin as hetrozygous state in 2 patients and their unaffected members of their family. It occurred at the evolutionary conservation of the amino acids of taperin according to alignment analysis. Two polymorphism, 157C>T and 318C>T, were found in the patients and the control group.

CONCLUSION

A novel Taperin mutation, A187S was detected in Chinese patients with prelingual nonsyndromic hearing loss, which may be relevant to hearing loss. Two polymorphism, 157C>T and 318C>T, were found in Chinese in our research. The carrier frequency for Taperin mutation is about 1.74% of prelingual nonsyndromic deafness in Chinese patients.

[Treatment of esophageal perforation complicated with lethal massive hemorrhage induced by foreign body]

OBJECTIVE

To explore the clinical characteristics and therapies for esophageal perforation complicated with lethal massive hemorrhage caused by esophageal foreign body.

METHOD

To retrospective analysis the treatment of massive hemorrhage at the carotid artery or aorta caused by esophageal foreign body in forty seven patients, Foreign body characters, surgical approaches, and postsurgical management were summarized.

RESULT

Among 24 patients with cervical esophageal foreign body, the object was removed either by esophagoscopy or through lateral cervical incision. After controlling carotid artery hemorrhage and repairing Fistula of artery from cervical incision, 19 patients survived. For the 23 patients with thoracic esophageal foreign body accompanied with aorta hemorrhea, thoracotomy was performed to remove the foreign body and repair the aortic fistula. Only 3 of these 23 patients recovered from the emergent surgery, other 20 patients died.

CONCLUSION

For the patients with esophageal foreign body inducing large vessel impingement, the most reliable therapeutic method is surgical repairing of arterial perforation and extraction of the foreign body via cervical or thoracic incision. Carotid ligation should be considered in patients with recurrent carotid hemorrhage. For the patient with mediastinitis, esophageal exclusion is recommended to prevent infection and to promote healing of aortic perforation after aortic fistula repairing.

Bilateral sudden hearing loss following habitual abortion: a case report and review of literature

Sudden sensorineural hearing loss (SSNHL) is usually unilateral and can be associated with tinnitus and vertigo. The most common causes of this disease are known to be the vascular and viral agents, but immune disorders are involved in the development of sudden deafness. The antiphospholipid syndrome (APS) is an acquired autoimmune system disorder, which is defined as the presence of antiphospholipid antibodies (APA) in the patient's blood, then cause venous and/or arterial thrombosis in various organs of the body, for example, thrombosis can occur in the placenta and/or the inner ear. As a result, it can cause abortion and/or sudden deafness. Bilateral SSNHL following habitual abortion is a rare clinical event. Here, we report a case of 32-year-old woman who presented with bilateral sudden hearing loss following recurrent pregnancy loss (RPL) as the first manifestation of primary antiphospholipid syndrome. Combine the literature, the diagnosis, clinical implication and treatment are discussed.

Effect of mitomycin on normal dermal fibroblast and HaCat cell: an in vitro study

OBJECTIVE

To evaluate the effects of mitomycin on the growth of human dermal fibroblast and immortalized human keratinocyte line (HaCat cell), particularly the effect of mitomycin on intracellular messenger RNA (mRNA) synthesis of collagen and growth factors of fibroblast.

METHODS

The normal dermal fibroblast and HaCat cell were cultured in vitro. Cell cultures were exposed to 0.4 and 0.04 mg/ml of mitomycin solution, and serum-free culture medium was used as control. The cellular morphology change, growth characteristics, cell proliferation, and apoptosis were observed at different intervals. For the fibroblasts, the mRNA expression changes of transforming growth factor (TGF)-β1, basic fibroblast growth factor (bFGF), procollagen I, and III were detected by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS

The cultured normal human skin fibroblast and HaCat cell grew exponentially. A 5-min exposure to mitomycin at either 0.4 or 0.04 mg/ml caused marked dose-dependent cell proliferation inhibition on both fibroblasts and HaCat cells. Cell morphology changed, cell density decreased, and the growth curves were without an exponential phase. The fibroblast proliferated on the 5th day after the 5-min exposure of mitomycin at 0.04 mg/ml. Meanwhile, 5-min application of mitomycin at either 0.04 or 0.4 mg/ml induced fibroblast apoptosis but not necrosis. The apoptosis rate of the fibroblast increased with a higher concentration of mytomycin (p<0.05). A 5-min exposure to mitomycin at 0.4 mg/ml resulted in a marked decrease in the mRNA production of TGF-β1, procollagen I and III, and a marked increase in the mRNA production of bFGF.

CONCLUSIONS

Mitomycin can inhibit fibroblast proliferation, induce fibroblast apoptosis, and regulate intracellular protein expression on mRNA levels. In addition, mitomycin can inhibit HaCat cell proliferation, so epithelial cell needs more protecting to avoid mitomycin's side effect when it is applied clinically.

[Clinical analysis on extramedullary plasmacytoma in the upper airway]

OBJECTIVE

To investigate the clinical manifestation, treatment and prognosis of extramedullary plasmacytoma(EMP) in the upper airway, and to improve the diagnosis and outcome of EMP treatment.

METHOD

Clinical data of 26 EMP cases were reviewed retrospectively, and then compared with multiple myeloma(MM) patients presenting with lesions in upper airway.

RESULT

Of 26 cases, 9 cases with the tumors occurred in nasal cavities, 7 in nasal sinuses, 6 in pharyngeal, 4 in throat, mainly manifesting with local masses and relevant symptoms. The manifestations of clinical, endoscopy findings and pathologic results in EMP patients were not distinguishable from the lesions of MM patients, while MM patients often accompanied by other findings, such as anemia and bone damage. Involvement of neck lymph nodes was more common in MM patients than in EMP patients. Ten patients were treated with surgery, and 16 patients with surgery and radiotherapy. Of the seven EMP patients with involvement of neck lymph nodes, four patients received additional chemotherapy besides surgery and radiotherapy, and no local relapse and MM happened in them, while of the three patients only received surgery and radiotherapy, one local relapse were found and one progressed to MM.

CONCLUSION

The diagnosis of EMPs mainly depends on pathological results. The judgment of pathologists and application of molecular biology technology are vital for the diagnosis of EMP in upper airway, and MM must be excluded very carefully in the diagnosis of EMP. Surgery combined with radiotherapy is the main treatment for EMP in the upper airway, and the prognosis is good but the follow-up should be taken. Besides surgery and radiotherapy, chemotherapy is beneficial for the EMP patients accompanied with lesions in neck lymph nodes.

[CD44 regulates epithelial-mesenchymal transition and metastasis in nasopharyngeal cancer cells]

OBJECTIVE

To study the correlation of CD44 with epithelial-mesenchymal transition(EMT) and metastasis in nasopharyngeal cancer cells, and explore the possible mechanism of CD44 regulates EMT and metastasis in nasopharyngeal cancer cells.

METHOD

The CD44 and EMT-associated proteins in 5-8F and 6-10B nasopharyngeal cancer cell lines were assayed by Western blotting. The erasion trace test was performed to observe the migratory ability of 5-8F and 6-10B nasopharyngeal cancer cells. Using lipid-mediated DNA transfection technique, the low metastatic nasopharyngeal cancer cells 6-10B were transfected in vitro with plasmid which contained CD44 gene, and then new nasopharyngeal cancer cells were obtained. The CD44 and EMT-associated proteins in 6-10B, empty vector transfected and CD44-transfected cells were assayed by Western blotting. The erasion trace test was performed to observe the alteration of migratory ability of nasopharyngeal cancer cells before and after CD44 transfection.

RESULT

The expression of CD44 and EMT-associated protein MMP-9 in 5-8F was higher than that in 6-10B, but EMT-associated protein E-Cadherin in 5-8F was lower than that in 6-10B. The migratory ability of 5-8F was higher than that of 6-10B. The expression of CD44 and MMP-9 were significantly higher in the CD44-transfected nasopharyngeal cancer cells than in the control groups. Compared with control groups, the migratory ability of CD44-transfected nasopharyngeal cancer cells was significantly increased.

CONCLUSION

CD44 positively regulates the metastatic ability of nasopharyngeal cancer cells, which is relevant to the process of EMT.

Hearing loss and PRPS1 mutations: Wide spectrum of phenotypes and potential therapy

OBJECTIVE

The purpose of this review was to evaluate the current literature on phosphoribosylpyrophosphate synthetase 1 (PRPS1)-related diseases and their consequences on hearing function.

DESIGN

A literature search of peer-reviewed, published journal articles was conducted in online bibliographic databases.

STUDY SAMPLE

Three databases for medical research were included in this review.

RESULTS

Mutations in PRPS1 are associated with a spectrum of non-syndromic to syndromic hearing loss. Hearing loss in male patients with PRPS1 mutations is bilateral, moderate to profound, and can be prelingual or postlingual, progressive or non-progressive. Audiogram shapes associated with PRPS1 deafness are usually residual and flat. Female carriers can have unilateral or bilateral hearing impairment. Gain of function mutations in PRPS1 cause a superactivity of the PRS-I protein whereas the loss-of-function mutations result in X-linked nonsyndromic sensorineural deafness type 2 (DFN2), or in syndromic deafness including Arts syndrome and X-linked Charcot-Marie-Tooth disease-5 (CMTX5).

CONCLUSIONS

Lower residual activity in PRS-I leads to a more severe clinical manifestation. Clinical and molecular findings suggest that the four PRPS1 disorders discovered to date belong to the same disease spectrum. Dietary supplementation with S-adenosylmethionine (SAM) appeared to alleviate the symptoms of Arts syndrome patients, suggesting that SAM could compensate for PRS-I deficiency.

[Expression of proteinase TMPRSS3 in mouse cochlea]

OBJECTIVE

To observe the expression of proteinase transmembrane protease, serine 3 (TMPRSS3) in mouse cochlea, and to investigate the significance of TMPRSS3 in the inner ear.

METHODS

The protein expression of TMPRSS3 in C57/BL mouse cochlea was identified and detected by immunohistochemistry and immunofluorescence. Different cochlear tissues, such as spiral ganglion neurons, corti organ, stria vascularis and so on, were separated to detect the gene expression of TMPRSS3 by real-time fluorescence quantitative polymerase chain reaction (qPCR). The cochlear tissues with different ages were collected and the expression of TMPRSS3 mRNA was detected by qPCR.

RESULTS

TMPRSS3 was mainly expressed in the spiral ganglion neurons, and there was TMPRSS3 mRNA in the cochlea in groups with different age. The expression level of TMPRSS3 mRNA was much weaker.

CONCLUSION

The distribution of TMPRSS3 was observed in many regions of the mouse cochlea, but mainly in the spiral ganglion neurons. This indicates that TMPRSS3 may be involved in the physiological functional regulation of the spiral ganglion neurons.

Diagnosis and treatment of nine cases with carotid artery rupture due to hypopharyngeal and cervical esophageal foreign body ingestion

The aim of our study is to present our experience in the diagnosis and treatment of patients with carotid artery rupture (CAR) due to foreign body ingestion. A total of nine admissions with CAR due to foreign body ingestion were recorded in Second Xiangya Hospital between 1969 and 2011. The carotid artery was sutured with muscle flap coverage in six cases, ligated in three cases. We retrospectively compared different surgical procedures of the patients and their clinical outcomes. Results show that CAR was found in all of these nine cases in imaging examinations or surgery. Among these six patients treated by suture of the carotid artery, five patients had a complete recovery without any complications, one patient underwent common carotid artery (CCA) ligation after suture surgery, but finally died of massive hemorrhage due to uncontrollable infection with carotid artery erosion. Among these three patients treated only by CCA ligation, one patient had no complications, one patient had hemiplegia, and one patient died of severe cerebral edema. Hence, timely diagnosis and open surgery are important for the patients of CAR due to foreign body ingestion. Suture of the carotid artery with muscle flap coverage is a better method compared with ligation of the carotid artery in the treatment of CAR.

Evaluation of intratympanic dexamethasone for treatment of refractory sudden sensorineural hearing loss

OBJECTIVE

To observe and compare the efficacy of intratympanic application of dexamethasone (DXM) for the treatment of refractory sudden sensorineural hearing loss (SSNHL), the DXM was given in three different ways: by tympanic membrane injection, by drip through a ventilation tube, and by perfusion through a round window catheter.

METHODS

We conducted a nonrandomized retrospective clinical trial involving 55 patients with refractory SSNHL. For 21 patients (the perfusion group), DXM (2.5 mg/0.5 ml) was perfused transtympanically through a round window catheter using an infusion pump for 1 h twice a day for 7 d giving a total amount of 35.0 mg. For 23 patients (the injection group), DXM (2.5 mg/time) was injected by tympanic membrane puncture at intervals of 2 d on a total of four occasions giving a total amount of 10.0 mg. For 11 patients (the drip group), DXM (2.5 mg/0.5 ml) was dripped via a ventilation tube placed by myringotomy, once on the first day and twice a day for the remaining 6 d giving a total amount of 32.5 mg. Thirty-two patients with refractory SSNHL who refused to undertake further treatments were defined as the control group. Hearing recovery and complications were compared among the groups. Hearing results were evaluated based on a four-frequency (0.5, 1.0, 2.0, 4.0 kHz) pure tone average (PTA).

RESULTS

Post-treatment audiograms were obtained one month after treatments were completed. The improvements in average PTA for the perfusion, injection, and drip groups were 9.0, 8.6, and 1.7 dB, respectively. Hearing improvement was significantly greater in the perfusion and injection groups than in the control group (1.4 dB) (P<0.05). In the perfusion group, 8 out of 21 patients (38.1%) had a PTA improvement of 15‒56 dB (mean 29.8 dB); in the injection group, 8 out of 23 patients (34.8%) had a PTA improvement of 16‒54 dB (mean 24.9 dB); in the drip group, 1 of 11 patients (9.1%) had a PTA improvement of 26.0 dB; in the control group, 3 out of 32 patients (9.4%) had a PTA improvement of 15‒36 dB (mean 14.9 dB).

CONCLUSIONS

Topical intratympanic application of DXM is a safe and effective method for the treatment of SSNHL cases that are refractory to conventional therapies.

Comparative proteomic analysis of secreted proteins from nasopharyngeal carcinoma-associated stromal fibroblasts and normal fibroblasts

Since the concept of the secretome (ensemble of proteins secreted and/or shed from cells) was proposed, it has become an attractive and challenging proteomic technology in recent years. However, secretome analysis still faces some difficulties mainly related to sample collection and preparation. In the present study, we established a reliable method for extracting secreted proteins by ultrafiltration centrifugation and conducting secretomic analysis. Accumulating evidence suggests that carcinoma-associated stromal fibroblasts (CAFs) play an important role in cancer initiation and progression. To investigate the expression patterns of secreted proteins from fibroblasts and to identify the secreted proteins involved in nasopharyngeal carcinoma (NPC) carcinogenesis, we conducted comparative secretome analysis between CAFs and normal fibroblasts. After two-dimensional gel electrophoresis (2-D PAGE), 11 significant spots were differentially expressed and identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS). These proteins may take part in the regulation of the tumor micro-environment through different processes. The expression level of galectin-1 in the CAF supernatant was also determined by ELISA. This study provides useful information and new clues for the further understanding of the regulatory mechanisms of CAFs in the NPC microenvironment.

[Expression of TMPRSS3 in the rat cochlea following kanamycin ototoxicity]

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.

Acute Mediastinitis Associated with Foreign Body Erosion from the Hypopharynx and Esophagus

Objective. Mediastinitis secondary to hypopharyngeal and esophageal foreign bodies is a rare but lethal complication. So far, no literature on a large scale has been reported. This investigation reviewed cases of mediastinitis associated with foreign body ingestion during the past 40 years.

Study Design. Case series with chart review.

Setting. Second Xiangya Hospital, Central South University.

Subjects and Methods. Of 2981 patients with hypopharyngeal and esophageal foreign body impaction included between 1969 and 2010, 93 had complications of acute mediastinitis. Four patients were dead within 4 hours after admission. The rest of the 89 patients underwent surgical drainage. Thirteen underwent primary repair (7 cases with suture, 6 cases with omentum onlay graft), and 9 patients underwent endoscopic stent placement at the same time.

Results. The mean (SD) time between ingestion and initial treatment of patients who developed mediastinitis was 7.72 (1.93) days, compared with 1.92 (1.41) days for those who did not ( P < .05). Morbidity was 3.1% and mortality was 30.1% (28/93), but the mortality of every decade has decreased from 38.7% in the 1970s to 8.3% today. Nine cases with local stent were all recovered.

Conclusions. Delay in initiating treatment and intrathoracic esophageal foreign bodies are the main risk factors of mediastinitis secondary to foreign body ingestion. Computed tomography plays an important role in diagnosis and guiding treatments. In conjunction with aggressive surgical debridement and drainage, endoscopic stent placement could be the optimal management for most patients.

Impaired membrane targeting and aberrant cellular localization of human Cx26 mutants associated with inherited recessive hearing loss

CONCLUSION

This study demonstrated that five Cx26 mutations (R32H, S199F, 572delT, 631-632delGT, and Y155X) affect gap junction (GJ) functions by causing impaired membrane targeting and aberrant cellular localization, and one mutation (R165W) leads to a constriction of the channel pore with no dye coupling.

OBJECTIVE

To investigate the pathogenetic roles of six recessive Cx26 mutations (p.R32H, p.R165W, p.S199F, c.572delT, c.631-632delGT, and p.Y155X), which have not been functionally analyzed in vitro.

METHODS

The six mutants and wild-type Cx26 (wtCx26) were cloned into the EcoRI and SalI sites of pEGFP-N1 vector. We transfected the seven constructs into HeLa cells, followed by analysis of their protein expression using the western blot method, study of the protein localizations and gap junction-plaques on the cytomembrane under confocal microscopy, and assessment of the dye coupling of the mutated GJ channels by intercellular dye transfer experiment.

RESULTS

p.R165W targeted the cytomembrane and formed GJ-like structures in adjacent HeLa cells, causing null dye coupling. The mutants (p.R32H, p.S199F, c.572delT, c.631-632delGT, and p.Y155X) failed to reach the cell surface, and perfectly co-localized with endoplasmic reticulum (ER) throughout the cells.

[Effect of brain-derived neurotrophic factor gene transfected bone-marrow mesenchymal stem cells on damaged cochlear spiral ganglion cells of guinea pigs]

OBJECTIVE

To investigate the protective role of brain-derived neurotrophic factor (BDNF) gene transfected bone-marrow mesenchymal stem cells (BMSC) on cochlear spiral ganglion cells (SGC) impaired by aminoglycoside antibiotics (AmAn).

METHODS

The differentiation of BMSC transfected by BDNF gene (BDNF-BMSC) were detected with immunohistochemical examination of Nestin, neuron-specific enolase (NSE), and glial fibrillary acid protein (GFAP) antibody in vitro. BDNF gene transfected BMSC were transplanted into the cochleae of guinea pigs deafened by amikacin, while the control groups were designed in which artificial perilymphatic fluid (APF), BMSC or BDNF gene was injected into cochleae alone. The cochleae were obtained on the week 1, 2 and 4 after injection, respectively, paraffin-embedded, and cut in a paramodiolar plane subsequently. The histopathological changes of cochleae were observed, the density of SGC was calculated by staining with HE, and the corresponding optical density (COD) was calculated with immunohistochemical staining using NSE antibody. And the protective role of various groups on the cochlear SGC were compared.

RESULTS

The positive staining rate of BDNF gene transfected BMSC with Nestin, NSE and GFAP antibody were all higher than that of BMSC in vitro (P < 0.01). After transplantation into cochleae, the differences of SGC density and COD among various groups were all significant on the same time points (P < 0.05). The SGC density and COD of the BDNF gene transfected BMSC group were the highest. The SGC density and COD of various groups on week 4 were all obviously decreased than those on week 1 and 2 (P < 0.05).

CONCLUSION

AmAn-induced SGC damage could be depressed by BMSC, BDNF gene or BDNF gene transfected BMSC transplantation into cochleae, while BDNF gene transfected BMSC showed the best protective role.

[Expression of brain-derived neurotrophic factor modified bone marrow mesenchymal stem cells in the cochlea of drug deafened guinea pigs and its protection role]

OBJECTIVE

To study the expression of brain-derived neurotrophic factor (BDNF) gene modified bone marrow mesenchymal stem cells (MSC) in the cochlea of drug-deafened guinea pigs and its protection to spiral ganglion cells (SGC).

METHODS

Guinea pigs deafened by subcutaneous injection of amikacin were randomly divided into two groups, BDNF gene modified bone marrow MSC were injected into the cochlea through fenestration of scala tympani in the experimental group, while artificial perilymphatic fluid were injected in the control group. Experimental animals were executed at 7 and 28 days post-operation. Expression of BDNF mRNA was examined by quantitate real time RT-PCR, histological images of cochlear sections were analyzed to calculate the cellular density of the SGC, and terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) was used to identify the apoptotic neurons.

RESULTS

The BDNF expressive level in experimental group was higher than in the control group at 7 d and 28 d post-operation, whose differences were both statistically significant (P < 0.01). And, It showed a higher abundance of ganglion cell numbers, as well as a decreased apoptotic index in experimental group compared with the control group at 7 d and 28 d post-operation, whose differences were all statistically significant (P < 0.01).

CONCLUSION

BDNF gene modified MSC could maintain expression for at least 28 days after transplantation into cochlea of drug deafened guinea pigs, and protect SGC.

[Expressions of LL-37 and IL-8 in chronic sinusitis with nasal polyps]

OBJECTIVE

To investigate the expressions of LL-37 and IL-8 in chronic sinusitis with nasal polyps.

METHOD

Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemical staining were used to detect the expressions of LL-37 and IL-8 in nasal polyp tissues of 31 patients with chronic sinusitis and inferior turbinate tissues of 11 patients with chronic rhinitis.

RESULT

LL-37 and IL-8 mRNA were all positively expressed in all nasal polyps and inferior turbinate tissues. There were significant increases of LL-37 and IL-8 mRNA expressions in nasal polyps compared with the inferior turbinate tissues (P < 0.01). There were also significant increases of positive expression rates of LL-37 and IL-8 protein in nasal polyps, compared with the inferior turbinate tissues (P < 0.01). There was a positive relationship between the mRNA and protein expressions of LL37 and IL-8 (P < 0.01).

CONCLUSION

The expressions of LL-37 and IL-8 in nasal polyps suggest that they may play a role in the pathogenesis of chronic sinusitis. Besides its innate immune, LL-37 could enhance human body's anti-infected function by increasing acquired immune.

[The incidence of facial nerve dehiscence at mastoidectomy and its risk factors]

OBJECTIVE

To study the incidence and locations of facial nerve dehiscence (FND) in mastoidectomy for the patients with cholesteatoma and chronic otitis media, and to determine its relevance as pre-operative prediction.

METHOD

Three hundred and fifteen ears (217 ears with cholesteatoma and 98 with chronic otitis media) undergoing mastoidectomy with or without tympanoplasties were selected for retrospective study, in which the incidence and locations of FND was studied, and the relevance for FND were analyzed by univariate test following by multivariate stepwise logistic regression.

RESULT

The presence of FND was 22.9% of total surgical procedures and the locations of FND were 93.1% in the tympanic segment, which was significantly higher than in the mastoid segment. The factors as otogenic facial paralysis, pathologic style (cholesteatoma or chronic otitis media) and lateral semicircular canal (LSC) fistula were related to FND, while others factors as sex, age, revision operations, preoperative complications, dural exposure, sigmoid sinus exposure were not risk factors for FND.

CONCLUSION

The incidence of FND was 22.9% in this study, the most common location for FND was in the tympanic segment, therefore, the facial nerves should be especially taken care in mastoidectomy for patients with presence of otogenic facial paralysis, cholesteatoma and LSC fistula.

[The expressions and clinical significance of tumor suppressor gene CX26 in laryngeal squamous cell carcinoma]

OBJECTIVE

To investigate the expressions of tumor suppressor gene CX26 mRNA and coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between CX26 gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma.

METHOD

Laryngeal carcinoma tissues (studying group), which takeda from the center of tumors and laryngeal normal tissues (control group) takeda at the place of 1.0 cm out of the edge of the tumors, were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression level of CX26 mRNA, and immunohistochemical staining (frozen section) was used to detect the expression of CX26 protein in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively.

RESULT

mRNA of CX26 gene was all positively expressed in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases by RT-PCR. However, CX26 mRNA was obviously down-regulated in laryngeal carcinoma tissues than that in laryngeal normal tissues (P < 0.05). Immunohistochemical staining showed CX26 protein was strong-positively expressed in laryngeal normal tissues in 34 cases (89.5%), while it was positively expressed in laryngeal carcinoma tissues in 18 cases (47.4%), and with the location alteration of CX26 protein in laryngeal carcinoma cells. There was significant difference between the expression rate of CX26 protein in laryngeal carcinoma tissues and in laryngeal normal tissues (P < 0.05). Meanwhile, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein of the laryngeal carcinoma tissues in the advanced stage patients group (III stage and IV stage) were significantly lower than these in the early stage patients group (I and II) (P < 0.05), and it was significantly lower in those who have a cervical lymph node metastasis than those without metastasis. (P < 0.05). Moreover, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein reduced along with the reduction of pathological differentiation, and there was significant difference among the well-differentiated group, moderately-differentiated group and poorly-differentiated group (P < 0.05).

CONCLUSION

CX26 gene may play an important role in the pathogenesis and development of laryngeal carcinoma and may be related to its prognosis.

[Clinical analysis of extramedullary plasmacytomas in the head and neck]

OBJECTIVE

To summarize the clinical features and the experiences of diagnosis and treatment of extramedullary plasmacytomas (EMPs), and to enhance the cure rates of EMPs.

METHOD

Clinical data of 8 patients with EMPs in head and neck, who treated in our hospital from Jan. 1990 to Dec. 2004, were reviewed. Of 8 cases, 3 cases with the tumors occurred in nasal cavities, 1 in maxillary sinus, 2 in nasopharynx, 1 in posterior wall of oropharynx.

RESULT

Eight patients who were all pathologic confirmed EMP accepted surgical resections of the tumors, and 4 of 8 cases were boosted radiation therapy post-operation. Four cases were still alive disease-free for more than 1, 5, 10 and 12 years after treatments, respectively. One died of local recurrence in 2 years, 1 died of multiple myeloma in 3 year, and 1 died of heart attack in 2 years after treatments, respectively. One lost follow-up.

CONCLUSION

EMPs in head and neck are low potential malignancy tumors. The diagnosis of EMPs mainly depends on clinical manifestations and pathological results. Surgery and radiation therapy are the main treatments for EMPs in head and neck.

[Reconstructive methods for hypopharynx and cervical esophagus]

OBJECTIVE

To review the surgical treatment for reconstructing hypopharynx and cervical esophagus after hypopharyngo-oesophagectomy, and to evalue its efficacy.

METHODS

Different methods were adopted to reconstruct the hypopharynx and cervical esophagus among 25 cases, including 14 cases of carcinoma of the hypopharynx and 11 of carcinoma of hypopharynx and cervical esophagus. In accordance with the standard of the International Union Against Cancer in 1997, the 25 cases were divided into different clinic stages, among which 5 were in T(2)N(0), 2 in T(2)N(1), 4 in T(3)N(0), 3 in T(3)N(1), 7 in T(4)N(1) and 3 in T(4)N(2). Treatment protocol was as follow: Pure operation for 5 cases, re-operation after radiotherapy for 2 cases, operation plus radiotherapy for 18 cases, laryngeal conservation operation for 8, and neck dissection for 21 cases. Reconstruction was done by using free jejunal transplantation, gastric pull-up, the laryngotracheal flap, and myocutaneous flap.

RESULTS

After the reconstruction, 3 cases of free jejunal graft and gastric pull-up, 4 of laryngotracheal flap recovered oral fleeding within 2 weeks. No serious complications occurred. After 18 cases underwent the myocutaneous flap reconstruction, no complications occurred in 10 patients, but there were different complications in 8 cases, including pharyngocutaneous fistula (6 cases), haryngoesphageal stenosis (7 cases), and pectoralis major myocutaneous flap necrotic (1 case). The 3-year survival rate was 38.9% (7/18).

CONCLUSION

Reconstruction with free jejunal graft, gastric pull-up, and laryngotracheal flap constitutes is a safe and reliable method to restore the continuity of the upper digestive tract after pharyngo-laryngo-oesophagectomy. After the reconstruction with myocutaneous flap, there is high incidence of pharyngocutaneous fistula and haryngoesophageal stenosis.

[Diagnosis and surgical treatment of the carotid body tumors]

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.