Utility of the psychomotor vigilance task in screening for obstructive sleep apnoea

PURPOSE

The study aimed to assess the performance of the PVT in patients with suspected OSA, evaluate its role in population screening for OSA.

METHODS

The NoSAS, STOP-Bang, ESS scores and PVT tests were performed after suspected OSA patients' admission, followed by PSG. Then we compared the PVT results, calculated the sensitivity, specificity and ROC curve of PVT, and analyzed the accuracy of STOP-Bang and NoSAS questionnaire combined with PVT in predicting OSA.

RESULTS

A total of 308 patients were divided into four groups based on AHI: primary snoring (2.74 ± 1.4 events/h, n = 37); mild OSA (9.96 ± 3.25 events/h, n = 65); moderate OSA (22.41 ± 4.48 events/h, n = 76); and, severe OSA (59.42 ± 18.37 events/h, n = 130). There were significant differences in PVT lapses (p < 0.001) and reaction time (RT, p = 0.03) among the four groups. The PVT lapses and RT were positively correlated with AHI (p < 0.001) and ODI (p < 0.001), and negatively correlated with LSpO2 (p < 0.001). When diagnosing OSA (AHI ≥ 5 events/h), the AUCs of PVT, ESS, STOP-Bang, and NoSAS were 0.679, 0.579, 0.727, and 0.653, respectively; the AUCs of STOP-Bang and NoSAS combined with PVT increased. After combined PVT, the diagnostic specificity of STOP-Bang and NoSAS at nodes with AHI ≥ 5, ≥ 15 and ≥ 30 events/h increased to varying degrees.

CONCLUSION

Patients with OSA exhibited impairment in the PVT, and the combination of the PVT and STOP-Bang or NoSAS scores can improve the diagnostic efficacy and specificity for OSA.

Effectiveness and safety of radiotherapy plus programmed death-1 inhibitors and lenvatinib in patients with advanced biliary tract carcinoma: a real-world study

BACKGROUND

Radiotherapy (RT) may function synergistically with immunotherapy and targeted agents (TA). This study aimed to assess the effectiveness and safety of RT combined with programmed death-1 (PD-1) inhibitors and lenvatinib in patients with relapsed or refractory advanced biliary tract carcinoma (BTC).

METHODS

This retrospective study included patients with relapsed or refractory advanced BTC who received RT combined with PD-1 inhibitors and lenvatinib at the Peking Union Medical College Hospital (PUMCH). Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and safety were evaluated.

RESULTS

Thirty-one patients who received RT combined with PD-1 inhibitors and lenvatinib as a second- or later-line therapy were analyzed. RT sites were mainly distributed in the liver lesions (64.5%) and lymph nodes (58.1%). The ORR and DCR were 32.3% (10/31; 95% CI: 14.8-49.7) and 87.1% (27/31; 95% CI: 74.6-99.6), respectively. The median PFS (mPFS) and median OS (mOS) were 7.9 (95% CI: 7.1-8.7) and 11.7 (95% CI: 8.3-15.0) months, respectively. Subgroup analyses of this cohort included 12 and 19 patients who received concurrent and salvage (> 6 weeks after commencing PD-1 inhibitor therapy) RT, respectively. The salvage RT group had higher mOS (11.7 vs. 10.5; p = 0.75) and mPFS (7.9 vs. 6.9; p = 0.85) than the concurrent RT group; however, statistical significance was not reached. All patients experienced any-grade adverse events (AEs), and excessive PD-1 inhibitors or RT toxicity were not observed.

CONCLUSIONS

RT, PD-1 inhibitors, and lenvatinib may be safely combined and have antitumor effectiveness in patients with advanced BTC.

Melatonin Alleviates the Oxygen-Glucose Deprivation/Reperfusion-Induced Pyroptosis of HEI-OC1 Cells and Cochlear Hair Cells via MT-1,2/Nrf2 (NFE2L2)/ROS/NLRP3 Pathway

Substantial evidence suggests that pyroptosis is involved in renal, cerebral, and myocardial ischemia-reperfusion injury. However, whether pyroptosis is involved in ischemia-reperfusion injury of cochlear hair cells has not been explored. In this study, we examined the effects of melatonin on the oxygen-glucose deprivation/reperfusion (OGD/R) of hair cell-like House Ear Institute-Organ of Corti 1 (HEI-OC1) cells and cochlear hair cells in vitro to mimic cochlear ischemia-reperfusion injury in vivo. We found that melatonin treatment protected the HEI-OC1 and cochlear hair cells against OGD/R-induced cell pyroptosis and reduced the expression level of ROS in these cells. However, these effects were completely abolished by the application of luzindole (a non-selective melatonin receptor blocker) and largely offset by the use of ML385 (an nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor). These findings suggest that melatonin alleviates OGD/R-induced pyroptosis of the hair cell-like HEI-OC1 cells and cochlear hair cells via the melatonin receptor 1A (MT-1) and melatonin receptor 1B (MT-2)/Nrf2 (NFE2L2)/ROS/NLRP3 pathway, which may provide credible evidence for melatonin being used as a potential drug for the treatment of idiopathic sudden sensorineural hearing loss in the future.

Pyroptosis: A Newly Discovered Therapeutic Target for Ischemia-Reperfusion Injury

Ischemia-reperfusion (I/R) injury, uncommon among patients suffering from myocardial infarction, stroke, or acute kidney injury, can result in cell death and organ dysfunction. Previous studies have shown that different types of cell death, including apoptosis, necrosis, and autophagy, can occur during I/R injury. Pyroptosis, which is characterized by cell membrane pore formation, pro-inflammatory cytokine release, and cell burst, and which differentiates itself from apoptosis and necroptosis, has been found to be closely related to I/R injury. Therefore, targeting the signaling pathways and key regulators of pyroptosis may be favorable for the treatment of I/R injury, which is far from adequate at present. This review summarizes the current status of pyroptosis and its connection to I/R in different organs, as well as potential treatment strategies targeting it to combat I/R injury.

Dual inhibition of autophagy and PI3K/mTOR pathway as a potential therapeutic strategy against laryngeal squamous cell carcinoma

Background

New and effective chemotherapy or targeted therapy strategies are needed against laryngeal squamous cell carcinoma (LSCC). We aimed to explore the antitumor effect of dual PI3K/mTOR inhibitor combined with autophagy suppression on LSCC and its underlying mechanism.

Methods

Hep-2 and AMC-HN-8 cell lines were treated with the Akt inhibitor LY294002, mTOR inhibitor rapamycin, and dual inhibitor NVP-BEZ235 separately. The biological characteristics of in vitro proliferation, cell cycle, apoptosis, migration, invasion, and autophagy were analyzed, and the expression levels of PI3K/Akt/mTOR pathway-related proteins were also measured. The in vivo effects of NVP-BEZ235 combined with inhibition of autophagy using pharmacological inhibitor was further assessed.

Results

Compared with Akt or mTOR inhibitor, NVP-BEZ235 had the most significant biological effects on LSCC cells. When combined with various autophagy inhibitors, along with siRNA against ATG7, NVP-BEZ235 showed a synergic antitumor effect in LSCC through increasing cell apoptosis and death both in vitro and vivo.

Conclusions

NVP-BEZ235 exerted potent antitumor effects on LSCC, especially when combined with the autophagy inhibitor both in vitro and vivo, providing convincing experimental data for new molecular targeted therapy for LSCC.

The volcanic relationship between HER activity and lattice constant of RuCo alloy nanofilm as a high efficient electrocatalyst

RuCo-ANFs with different proportions can be successfully prepared by magnetron sputtering, and their lattice constants can be adjusted accurately. In the RuCo-ANF, there is an obvious electronic interaction between Ru...

Promoting effect of amorphous support on ruthenium-based catalyst for electrochemical hydrogen evolution reaction

Nano-network Ru with definite lattice defects on amorphous Co nanosheets is obtained for the first time. Amorphous Co support can promote the surface Ru to obtain special morphology and modified...

Exposure assessment for Cox proportional hazards cure models with interval-censored survival data

Mixture cure models have been developed as an effective tool to analyze failure time data with a cure fraction. Used in conjunction with the logistic regression model, this model allows covariate-adjusted inference of an exposure effect on the cured probability and the hazard of failure for the uncured subjects. However, the covariate-adjusted inference for the overall exposure effect is not directly provided. In this paper, we describe a Cox proportional hazards cure model to analyze interval-censored survival data in the presence of a cured fraction and then apply a post-estimation approach by using model-predicted estimates difference to assess the overall exposure effect on the restricted mean survival time scale. For baseline hazard/survival function estimation, simple parametric models as fractional polynomials or restricted cubic splines are utilized to approximate the baseline logarithm cumulative hazard function, or, alternatively, the full likelihood is specified through a piecewise linear approximation for the cumulative baseline hazard function. Simulation studies were conducted to demonstrate the unbiasedness of both estimation methods for the overall exposure effect estimates over various baseline hazard distribution shapes. The methods are applied to analyze the interval-censored relapse time data from a smoking cessation study.

A Prospective Study of the Effect of Tinnitus Sound Matching Degree on the Efficacy of Customized Sound Therapy in Patients with Chronic Tinnitus

OBJECTIVES

The aim of this study was to explore and compare the customized sound therapy effect between tinnitus sound matching and nonmatching patients in tinnitus customized sound therapy and therapy-related influencing factors.

METHODS

This prospective study investigated a total of 100 patients with unilateral chronic tinnitus who received customized sound therapy. The participants were dichotomously divided into matching (group A) and nonmatching (group B) groups after 4 stages of tinnitus matching via the tinnitus assistant app (provided by Sound Ocean Company, SuZhou, China). Each group consists of 50 participants. Before and 6 months after the treatment, Hospital Anxiety and Depression Scale (HADS), tinnitus handicap inventory (THI), and tinnitus loudness Visual Analog Scale (VAS) were used to evaluate the customized sound therapy effect and explore other related influencing factors.

RESULTS

(1) The HADS-A, HADS-D, THI, and VAS scores of 2 groups were both significantly decreased after treatment. (2) The HADS-A and THI scores improved markedly in group A than that in group B, which could be related to the hearing loss of the tinnitus side ear before treatment; the lighter the degree of hearing loss, the better the improvement. No statistically significant differences were detected in HADS-D and VAS scores between the 2 groups, and also, these were not related to the degree of hearing loss. The differences in age, gender, and tinnitus duration did not show any statistically significant effect on the improvement of the 2 groups.

CONCLUSIONS

Both tinnitus sound matching and nonmatching of the customized sound therapy brought a significant effect to tinnitus participants. Our study also suggests that THI and HADS-A scores of those with tinnitus matching participants improved markedly as compared to those of nonmatching participants, and the customized sound therapy effect is negatively correlated with the severity of hearing loss.

SGN nerve filaments develop synapses with IHCs earlier than with OHCs in C57BL/6 mouse inner ear

OBJECTIVE

To explore the connections between hair cells and spiral ganglion neurons (SGNs) during the development of the C57BL/6 mouse inner ear.

MATERIALS AND METHODS

The specimens of C57BL/6 mouse inner ear, from E15 (embryo day 15) to adult mouse, were collected; immunohistochemistry was employed to explore the frozen sections of specimens.

RESULTS

The development of cochlea starts sequentially from the basal turn to the apex turn. Morphological development of SGNs occurs mainly from E16 to P12 (postnatal day 12). Hair cells appear from E18 to P12, and inner hair cells (IHCs) develop earlier than outer hair cells (OHCs). The connections between hair cells and SGNs begin to develop during E18-P1, morphologically resemble mature synapses during P8-P12, and completely mature in adult mice.

CONCLUSIONS

The genesis of auditory ribbon synapse occurs from E18 to P1. Synchronized with the development of SGNs and hair cells, the functional filaments remain connected to hair cells, while the spare ones get disconnected from the surface of hair cells. Connections between SGN nerve filaments and IHCs occur earlier than those between SGN nerve filaments and OHCs.

Evaluations on the stability and bio-compatibility of a new piezoelectric microphone for the implantable middle ear microphone

BACKGROUND

A new floating piezoelectric microphone (NFPM), driven by the acoustic vibration of the ossicles, has been manufactured in the lab.

OBJECTIVES

This study aimed at exploring the stability and bio-compatibility of this NFPM.

MATERIALS AND METHODS

The NFPM was implanted into the cat tympanic cavity by clamping it to the handle of the malleus, and then a temporal bone computed tomography (CT) plain scan and three dimensional reconstruction were performed to observe its coupling with the handle of the malleus. After six months of implantation, cats' blood samples were taken for pro-inflammatory factor analysis. Then, the operative cavity was opened to check the NFPM, the auditory ossicular chain and some granulation tissue surrounding the NFPM.

RESULTS

The NFPM was firmly clamped to the handle of the malleus of the cats during the six months of implantation. Besides, there was no obvious systemic inflammatory response in the experimental animals. In addition, local proliferation of granulation tissue occurred in the tympanic cavity without hampering the movement of the auditory ossicle,or causing ischemia of the auditory ossicle.

CONCLUSION

The NFPM could be implanted in our experimental cats for a long period of time and had good bio-compatibility.

Sound localization, speech and tone recognition for stimuli presented from the rear in bilateral cochlear implant users

OBJECTIVE

To assess any differences in spatial listening ability of cochlear implant recipients when using both or only one of two bilateral cochlear implants (BCIs) for stimuli originating from behind the subject.

DESIGN

Twelve loudspeakers were placed in the rear horizontal plane of the subjects to test the sound localisation performance of BCI users and normal-hearing listeners (NHLs) with or without interfering noise. Stimuli were presented via two rear loudspeakers simultaneously during the speech recognition test. In the tone recognition test, another anechoic chamber was used with stimuli presenting from a loudspeaker behind the participants.

STUDY SAMPLE

Twenty-seven NHLs and eleven BCI users.

RESULTS

Average root-mean-square (RMS) error for the bilateral condition was significantly lower than that for the right and left cochlear implant (CI) conditions with or without interfering noises (p < 0.05). Average speech or tone recognition scores for the bilateral condition and the right and left CI conditions were not statistically significant (p > 0.05).

CONCLUSION

Sound localisation with BCIs was significantly more accurate than with either implant alone. Speech and tone recognition scores were not better with two compared to those of one activated implant. Given the small number of subjects, the results should be considered as preliminary.

Transarterial Chemoembolization Followed by Radiotherapy Versus Sandwich Treatment for Unresectable or Ablative Hepatocellular Carcinoma

Objective:

Our objective is to assess whether the outcome of intrahepatic unresectable or ablative hepatocellular carcinoma (HCC) could be improved by supplemental transarterial chemoembolization (TACE) following initial treatment of TACE with 3-dimensional conformal radiotherapy (3DCRT), compared to TACE followed by 3DCRT alone.

Methods:

We retrospectively analyzed intrahepatic unresectable or ablative HCC patients who underwent TACE, followed by 3DCRT with or without additional TACE, from June 2010 to December 2016 at our institution. Survival was assessed using the Kaplan-Meier method and compared with the log-rank test. Cox regression analyses were used to identify factors that influenced prognosis. Toxicity profiles were evaluated using CTCAE 4.0.

Results:

27 patients received TACE with 3DCRT (TR group) and 11 received additional TACE following TACE and 3DCRT (sandwich group), respectively. The median intrahepatic progression-free survival (IPFS), progression-free survival (PFS), and overall survival (OS) in the TR group and sandwich group were 5.4 months vs. 17 months (P = 0.018), 5.4 months vs. 17 months (P = 0.008), and 13.5 months vs. 29.2 months (P = 0.011), respectively. Multivariate Cox regression demonstrated that TACE followed by radiotherapy alone had a shorter IPFS (HR: 2.516, 95% CI (1.136-5.570), P = 0.023) and PFS (HR: 2.637, 95% CI (1.182-5.880), P = 0.018) compared with the sandwich treatment. Hepatitis B virus reactivation occurred in 1 patient in the sandwich group. Myleosuppresion was considered a grade 3/4 adverse event.

Conclusion:

Unresectable or ablative HCC patients possibly benefit from the combination of TACE and 3DCRT followed by additional TACE therapy, compared with TACE followed by 3DCRT alone.

AuIr alloy with arbitrarily adjustable lattice parameters as a highly efficient electrocatalyst for the oxygen reduction reaction

AuIr alloy nanoparticles were successfully prepared without using surfactants for the first time despite Au and Ir being immiscible according to phase diagrams. The lattice parameters of the AuIr alloy can be adjusted arbitrarily. The oxygen reduction reaction (ORR) activity of Au5Ir5 alloy is better than that of Au or Ir, and the oxygen evolution reaction (OER) activity of the Au5Ir5 alloy is as good as that of Ir in alkaline solution.

The Atoh1 expression levels are correlated with the arrangement, ciliary morphology, and electrophysiological characteristics of ectopic hair cell-like cells

Previous reports have suggested that the level and duration of Atoh1 expression are correlated with the survival, arrangement and stereociliary bundle-related morphology of hair cells during development, but whether Atoh1 expression levels are correlated with the arrangement, bundle formation and electrophysiological characteristics of newly formed hair cells is unknown. To address this question, cultured cochlear explants obtained from neonatal rats were treated with different titers of a human adenovirus serotype 5 (Ad5) vector encoding Atoh1 and/or EGFP (EGFP-Atoh1+/-). The results showed that higher EGFP-Atoh1 concentrations led to higher initial Atoh1 mRNA expression levels and induced greater numbers of ectopic hair cell-like cells (EHCLCs) in the lesser epithelial ridge (LER). Furthermore, gradual increases in the number of EHCLCs were associated with the progressive conversion of the LER region similarly to that of hair cells during development. Some of the cilia on EHCLCs with higher Atoh1 expression were regularly arranged in a manner similar to that of normal hair bundles. As demonstrated through patch clamp recordings, high Atoh1 expression was associated with significantly decreased proportions of cells with I_h currents, significantly reduced proportions of transient potassium channel currents, and potassium channel currents with a greatly increased mean amplitude, which indicated that EHCLCs with high Atoh1 expression were more mature than those with low Atoh1 expression. Overall, the evidence suggests that the Atoh1 expression levels affect not only the arrangement and ciliary morphology of hair cells but also the electrophysiological characteristics of Atoh1-induced EHCLCs, and these findings provide important guidance for future therapies aimed at treating deafness.

Peroxiredoxin1 promotes cell proliferation, migration and invasion of colorectal cancer via p38MAPK signaling

OBJECTIVE

Peroxiredoxin1 (PRDX1), a class of thiol peroxidases, is a multifunctional protein. We aimed at analyzing the effect of PRDX1 on proliferation, apoptosis, migration and invasion of colorectal cancer and to investigate the potential mechanism.

MATERIALS AND METHODS

Western blot and PCR were used to validate the silencing efficiency in SW480 cell by transfection of PRDX1-siRNA. The cell proliferation was detected by Cell Counting Kit-8 (CCK-8) test. Flow cytometry Annexin V/PI double staining was used to analyze cell apoptosis. Transwell and scratch test were used to detect the migration and invasion of cells. Signal pathway protein expression was analyzed by Western blot.

RESULTS

The expression of PRDX1 in SW480 cells could be reduced by siRNA effectively. The cell proliferation, migration and invasion were reduced significantly compared with control group after down-regulation of PRDX1 (p<0.05), while the cell apoptosis was enhanced significantly (p<0.05). The ratio of phospho-p38 mitogen-activated protein kinases (p-p38) /p38 mitogen-activated protein kinases (p38) was down-regulated after the down-regulation of PRDX1 (p<0.05). The ratio of phospho-c-Jun N-terminal protein kinase (p-JNK)/c-Jun N-terminal protein kinase (JNK) and phospho-extracellular regulated protein kinases (p-ERK)/extracellular regulated protein kinases (ERK) showed changes with no significant difference (p>0.05).

CONCLUSIONS

Down-regulation of PRDX1 in colorectal cancer SW480 cells could inhibit the cell proliferation, migration, invasion, and induce cell apoptosis. This is very likely to be achieved by activating the p38MAPK-signaling pathway.

A nano AuTiO2-x composite with electrochemical characteristics of under-potential deposition of H (H-UPD) as a highly efficient electrocatalyst for hydrogen evolution

An obvious H-UPD for a nano AuTiO2-x composite has been found for the first time in terms of the electrochemical characteristics of the Au composite. The electronic effect between Au and TiO2 and the oxygen vacancy defect would change the adsorption energy of H and HER activity. The HER activity of the AuTiO2-x electrode is 6.44 times that of the Au electrode.

Triptolide induces toxicity in inner ear stem cells via promoting DNA damage

Emerging evidence and clinical case reports have observed a risk of cytotoxic effects of triptolide in patients. We aimed to investigate the triptolide-induced toxicity in mouse inner ear stem cells. The utricular sensory epithelium from adult BALB/C6 mice was used for the isolation of inner ear stem cells. Sphere formation assay was applied to examine the stemness of the cells. Cell count kit-8 and Bromodeoxyuridine assays were employed to detect the cell proliferation ability. Cell apoptosis was measured with Annexin V-FITC & propidium iodide Apoptosis kit. The relative expression levels of gamma H2A histone family member X (γH2AX), tumor suppressor p53-binding protein 1 (53BP1) and optic atrophy 1 (OPA-1) were measured by Western Blot. Mitochondrial function was analyzed by the MitoGreen green-fluorescent mitochondrial dye kit. Triptolide significantly inhibited the cell viability and proliferation and suppressed the capability of sphere formation. Furthermore, triptolide induced apoptosis as indicated by increased expression of DNA damage repair markers γH2AX and 53BP1. Moreover, triptolide influenced the function of mitochondria by inducing the cleavage of OPA-1. Our work clarifies the toxicity of triptolide in mouse inner ear stem cells, which provides clues of the toxicology mechanism for future studies and basis for clinical use.

A note on misspecification in general linear models with correlated errors for the analysis of crossover clinical trials

Among various approaches to the repeated measures analysis in crossover clinical trials, the general linear models (GLMs) with correlated errors attract substantial attention due to their simplicity in model specification, implementation, and interpretation. The goal of this research note is to conduct simulation studies to numerically investigate the impact of model misspecification in the GLMs with correlated errors in the analysis of crossover trials. A series of synthetic two-treatment and three-treatment crossover trials were designed, and simulation studies were conducted to assess how treatment effect estimation, type I error rates, and power can be affected by misspecified period effects, carryover effects, and variance-covariance structures in the GLMs. Numerical studies confirm that (i) the GLMs with terms for both carryover and period effects and with an unstructured variance-covariance matrix can provide unbiased treatment effect estimates and control of Type I error rates and that (ii) misspecification in either period effects, carryover effects, or covariance structures in the GLMs can induce inflated type I error, declined power, or biased treatment effect estimates. Although methodologic contribution of this research note is minimal, we provide practical recommendations and advice to pharmaceutical sponsors and other investigational drugs and device applicants in designing and analyzing crossover trials using the GLMs with correlated errors.

Mimic Cochlear Implant Surgery-Induced Cochlear Infection Fails to Further Damage Auditory Pathway in Deafened Guinea Pigs

Background

Kanamycin and subsequent furosemide administration was applied to the healthy guinea pigs to induce deafness.

Material/Methods

Of the deafened guinea pigs, 10 were further infused with anti-infection procedures (Group B) and the other 10 animals did not undergo anti-infection procedures (Group C). In Group B, the deafened animals were able to restore cochlear and middle ear functions following the anti-infection procedure. In Group C, all animals developed cochlear and middle ear infections.

Results

Compared to the healthy guinea pigs, hair cells and spiral ganglion neurons (SGN) of deafened animals (in Group B and Group C) were severely damaged. SGN density of deafened animals was significantly lower than that of healthy control animals in all ear turns except the basal turn. There was no significant difference between Group B and Group C in SGN density. The average optical density value of neurofilaments of deafened animals was also significantly decreased after the ototoxic drug administration. Notably, the density of the neurons in the cochlear nucleus region (CNR) of the brainstem were not significantly different between the healthy control guinea pigs and deafened animals.

Conclusions

Mimic cochlear implant surgery-induced cochlear infection caused no significant damage to the auditory pathway in ototoxic drug-induced deafened guinea pigs.

Celastrol enhances Atoh1 expression in inner ear stem cells and promotes their differentiation into functional auditory neuronal-like cells

We aimed to investigate the beneficial effect of Celastrol on inner ear stem cells and potential therapeutic value for hearing loss. The inner ear stem cells were isolated and characterized from utricular sensory epithelium of adult mice. The stemness was evaluated by sphere formation assay. The relative expressions of Atoh1, MAP-2 and Myosin VI were measured by RT-PCR and immunoblotting. The up-regulation of MAP-2 was also analysed with immunofluorescence. The in vitro neuronal excitability was interrogated by calcium oscillation. The electrophysiological property was determined by inward current recorded on patch clamp. Our results demonstrated that Celastrol treatment significantly improved the viability and proliferation of mouse inner ear stem cells, and facilitated sphere formation. Moreover, Celastrol stimulated differentiation of mouse inner ear stem cells to neuronal-like cells and enhanced neural excitability. Celastrol also enhanced neuronal-like cell identity in the inner ear stem cell derived neurons, as well as their electrophysiological function. Most notably, these effects were apparently associated with the upregulation of Atoh1 in response to Celastrol treatment. Celastrol showed beneficial effect on inner ear stem cells and held therapeutic promise against hearing loss.

Junctional E-cadherin/p120-catenin Is Correlated with the Absence of Supporting Cells to Hair Cells Conversion in Postnatal Mice Cochleae

Notch inhibition is known to generate supernumerary hair cells (HCs) at the expense of supporting cells (SCs) in the mammalian inner ear. However, inhibition of Notch activity becomes progressively less effective at inducing SC-to-HC conversion in the postnatal cochlea and balance organs as the animal ages. It has been suggested that the SC-to-HC conversion capacity is inversely correlated with E-cadherin accumulation in postnatal mammalian utricles. However, whether E-cadherin localization is linked to the SC-to-HC conversion capacity in the mammalian inner ear is poorly understood. In the present study, we treated cochleae from postnatal day 0 (P0) with the Notch signaling inhibitor DAPT and observed apparent SC-to-HC conversion along with E-cadherin/p120ctn disruption in the sensory region. In addition, the SC-to-HC conversion capacity and E-cadherin/p120ctn disorganization were robust in the apex but decreased toward the base. We further demonstrated that the ability to regenerate HCs and the disruption of E-cadherin/p120ctn concomitantly decreased with age and ceased at P7, even after extended DAPT treatments. This timing is consistent with E-cadherin/p120ctn accumulation in the postnatal cochleae. These results suggest that the decreasing capacity of SCs to transdifferentiate into HCs correlates with E-cadherin/p120ctn localization in the postnatal cochleae, which might account for the absence of SC-to-HC conversion in the mammalian cochlea.

Cell proliferation during hair cell regeneration induced by Math1 in vestibular epithelia in vitro

Hair cell regeneration is the fundamental method of correcting hearing loss and balance disorders caused by hair cell damage or loss. How to promote hair cell regeneration is a hot focus in current research. In mammals, cochlear hair cells cannot be regenerated and few vestibular hair cells can be renewed through spontaneous regeneration. However, Math₁ gene transfer allows a few inner ear cells to be transformed into hair cells in vitro or in vivo. Hair cells can be renewed through two possible means in birds: supporting cell differentiation and transdifferentiation with or without cell division. Hair cell regeneration is strongly associated with cell proliferation. Therefore, this study explored the relationship between Math₁-induced vestibular hair cell regeneration and cell division in mammals. The mouse vestibule was isolated to harvest vestibular epithelial cells. Ad-Math₁-enhanced green fluorescent protein (EGFP) was used to track cell division during hair cell transformation. 5-Bromo-2′-deoxyuridine (BrdU) was added to track cell proliferation at various time points. Immunocytochemistry was utilized to determine cell differentiation and proliferation. Results demonstrated that when epithelial cells were in a higher proliferative stage, more of these cells differentiated into hair cells by Math₁ gene transfer. However, in the low proliferation stage, no BrdU-positive cells were seen after Math₁ gene transfer. Cell division always occurred before Math₁ transfection but not during or after Math₁ transfection, when cells were labeled with BrdU before and after Ad-Math₁-EGFP transfection. These results confirm that vestibular epithelial cells with high proliferative potential can differentiate into new hair cells by Math₁ gene transfer, but this process is independent of cell proliferation.

Contrasting results of tests of peripheral vestibular function in patients with bilateral large vestibular aqueduct syndrome

OBJECTIVE

To analyze and summarize the effect of bilateral large vestibular aqueducts in peripheral vestibular organ function.

METHODS

Eighteen patients with bilateral large vestibular aqueduct syndrome (LVAS; Study Group) and 18 healthy volunteers (Control Group) were investigated using audiometry, caloric test, sensory organization test (SOT), and vestibular-evoked myogenic potential (VEMP) tests.

RESULTS

All 18 patients (36 ears) exhibited sensorineural hearing loss. For cervical VEMP (cVEMP), the Study Group showed lower thresholds (Study Group vs.

CONTROL GROUP

71.4vs. 75.3dBnHL; p=0.006), N1 latencies (24.1vs. 25.2ms; p=0.026) and shorter P1 (15.3vs. 16.6ms; p=0.003), and higher amplitudes (400.7vs. 247.2µV; p<0.001) than the Control Group. For ocular VEMP (oVEMP), the Study Group had lower thresholds (79.3vs. 81.8dBnHL; p=0.046) and higher amplitudes (40.6vs. 14.4µV; p<0.001) than the Control Group. Fourteen of 16 patients (87.5%) who completed caloric tests had abnormal results, and 10 of 18 patients (55.6%) exhibited abnormal results in SOTs.

CONCLUSIONS

The hyperfunction of vestibular test in otolithic organs and the hypofunction of vestibular test in semicircular canals, as well as the dysfunction in the balance test were demonstrated in patients with LVAS.

SIGNIFICANCE

Our findings can help clinicians gain a better understanding of the characteristics of vestibular organ function in patients with LVAS, which can facilitate optimal targeted treatment.

Allergic rhinitis and allergy are risk factors for otitis media with effusion: A meta-analysis

OBJECTIVE/HYPOTHESIS

We systematically reviewed the associations between allergic rhinitis or allergy and otitis media with effusion, by reference to published data.

STUDY DESIGN

A meta-analysis of case-controlled studies.

DATA SOURCE

Five databases (Pubmed, Highwire, Medline, Wanfang, and China National Knowledge Infrastructure) were searched for relevant studies in the English language published prior to November 12, 2015.

STUDIES CHOSEN

Studies with clearly defined experimental and control groups, in which the experimental groups had otitis media with effusion together with allergic rhinitis or allergy, were selected.

METHODS

We performed a meta-analysis on data from the identified cross-sectional and case-controlled studies using fixed- or random-effects models (depending on heterogeneity). We used Reviewer Manager 5.3 software to this end.

RESULTS

Seven studies met the inclusion criteria. The prevalence of allergic rhinitis in patients with otitis media with effusion and the control groups differed significantly in three studies (P<0.00001), as did the prevalence of allergy (in six studies; P=0.003).

CONCLUSION

Allergic rhinitis and allergy appear to be risk factors for otitis media with effusion.

Activation of ETA Receptor by Endothelin-1 Induces Hepatocellular Carcinoma Cell Migration and Invasion via ERK1/2 and AKT Signaling Pathways

Endothelin-1 (ET-1), a member of endothelins family, binds to ETA receptor (ETAR) and ETB receptor to exert its role in multiple cellular processes. Although ET-1 and its receptors has been reported to be overexpressed in many cancers, and overexpression of ET-1 is able to trigger hepatocarcinogenesis in zebrafish, the functions of ET-1 and its receptors in hepatocellular carcinoma (HCC) cell migration and invasion remain unclear. In the present study, we found that ETAR was greatly expressed in HCC cells and HCC tissues. ETAR expression as well as ET-1 expression was associated with vascular invasion and tumor stage in HCC. Activation of ETAR by ET-1 dose-dependently promoted cell migration and invasion of HCC cells, while silencing of ETAR by siRNA or blocking of ETAR by specific inhibitor resulted in significant reduction in ET-1-mediated migration and invasion. Furthermore, ET-1 induced activation of ERK1/2 and AKT and increased MMP-3 production via ETAR. In addition, using inhibitors of ERK1/2 and AKT, we found that ERK1/2 and AKT pathways were both involved in ETAR-mediated migration, invasion, and MMP-3 production. Taken together, our findings suggest that activation of ETAR by ET-1 promotes HCC cell migration and invasion via activating ERK1/2 and AKT signaling pathways and upregulating MMP-3 expression. Thus, ETAR may play an important role in the progress of HCC.

The hepatitis B virus reactivation after transarterial chemoembolization in Chinese hepatocellular carcinoma patients with low serum hepatitis B virus DNA level

Objective

To investigate the reactivation of the hepatitis B virus (HBV) following transarterial chemoembolization (TACE) in Chinese hepatocellular carcinoma (HCC) patients with low serum HBV DNA level, and to analyze the factors related to HBV reactivation in HCC patients with low serum HBV DNA level.

Methods

From November 2011 to January 2014, 109 patients newly diagnosed with HCC with an HBV DNA level less than 2,000 IU/mL were enrolled in the study. These patients underwent at least two TACE procedures and were followed-up for at least 3 months to assess the reactivation of HBV DNA. Ten variables were compared in patients with and without HBV reactivation to evaluate the factors related to HBV reactivation in HCC patients with low serum HBV DNA level.

Results

Of 109 HCC patients with low level HBV DNA, nine patients were HBeAg-positive, the other 100 patients were HBeAg-negative. Twenty-three of 109 (21.1%) patients developed HBV reactivation after TACE. Of nine HBeAg-positive patients, 55.6% (5/9) developed HBV reactivation, while in 100 HBeAg-negative patients, the rate of HBV reactivation was 18% (18/100) (P=0.019). Of ten variables of patients with low level HBV DNA, the levels of AFP and HBeAg status were found to be significantly correlated with HBV reactivation. Nevertheless, on binary logistic regression analysis, only HBeAg-positive status was the independent predictor of HBV reactivation in HCC patients with low serum HBV DNA level (odds ratio, 7.41; P=0.013).

Conclusion

HCC patients with low serum HBV DNA level still remain associated with risk of viral reactivation after TACE, and HBeAg-positive HCC patients have a higher risk than patients with HBeAg-negative status.

ABCG2 regulated by MAPK pathways is associated with cancer progression in laryngeal squamous cell carcinoma

ATP-binding cassette, subfamily G, member 2 (ABCG2) overexpression has been associated with multidrug resistance and cancer progression by promoting proliferation and/or suppressing apoptosis, but how this process happens remains to be determined. In this study, the roles and the mechanisms of ABCG2 in the progression of Laryngeal squamous cell carcinoma (LSCC) were investigated. We found that introduction of ABCG2 siRNA into Hep-2 and Hep-2T cells significantly enhanced the intracellular accumulation of mitoxantrone (MX). Down-regulation of ABCG2 by transient RNAi inhibited cell proliferation and blocked cell cycle progression by regulating the expression of cyclin D3 and p21 Cip1. ABCG2 silence also induced cell apoptosis by regulating the expression of surviving, bcl-2 and the cleavage of poly (ADP-ribose) polymerase (PARP) in Hep-2 and Hep-2T cells. ABCG2-specific inhibitor, fumitremorgin C (FTC), and mitogen-activated protein kinase (MAPK) pathway inhibitor, U0126, inhibited cell proliferation and promoted cell apoptosis by degrading endogenous ABCG2 in Hep-2T cells. Furthermore, inhibition of MAPK pathway by U0126 enhanced anti-cancer effects of MX in vivo. In conclusion, suppression of ABCG2 inhibits the procession of LSCC tumor growth by regulating cell proliferation and apoptosis. Our data also provide more evidence for the importance of the MAPK pathway as a suitable therapeutic target for LSCC.

Association between glutathione S-transferase T1, M1, and P1 genotypes and the risk of colorectal cancer

Glutathione S-transferases (GSTs) are enzymes which play an important role in the neutralization of toxic compounds and eradication of electrophilic carcinogens. Genetic polymorphisms within the genes encoding for GSTs may therefore cause variations in their enzyme activity, which may in turn influence the interindividual susceptibility to cancers. In this study, we aimed to investigate the association between genetic polymorphisms of GSTT1, GSTM1, and GSTP1 and the risk of colorectal cancer (CRC) in 264 cases and 317 controls in a Chinese population. Genotyping was performed by using multiplex PCR (for GSTT1 and GSTM1) and PCR-RFLP (for GSTP1) methods. The association between the polymorphic genotypes and CRC risk was evaluated by deriving odds ratios (ORs) and 95% confidence intervals (CIs) using unconditional logistic regression analysis. Our results showed that individuals with GSTT1 and GSTM1 null genotypes exhibited a higher risk of CRC (GSTT1, OR,1.66; 95% CI, 1.20-2.31, P=0.003; GSTM1, OR,1.57; 95% CI,1.13-2.18, P=0.007), while no association was observed for GSTP1 (P heterozygous=0.790 or P variant=0.261). Furthermore, individuals who simultaneously carried the null genotypes for both GSTT1 and GSTM1 showed a stronger risk association (OR, 1.95; 95% CI, 1.33-2.85; P<0.001). In conclusion, the GSTT1 and GSTM1 polymorphisms, but not GSTP1, may modulate the CRC risk among Chinese.

Association between carcinoembryonic antigen levels and the applied value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in post-operative recurrent and metastatic colorectal cancer

Positron emission tomography (PET) using ¹⁸F-fluorodeoxyglucose has been widely used for analyzing cellular metabolism. The present study aimed to evaluate the association between the diagnostic value of PET/computed tomography (CT) in patients with post-operative recurrent and metastatic colorectal cancer (CRC), and the different levels of carcinoembryonic antigen (CEA). A total of 105 suspected recurrent and metastatic CRC patients (67 males and 38 females; mean age, 48.5 years) were included in this retrospective study. All the patients underwent PET/CT examination. The differences in the PET/CT diagnostic values of CEA-positive and -negative patients with recurrent CRC following surgery were retrospectively analyzed and compared. Among the 105 CRC patients, 87 exhibited recurrence and metastasis, as confirmed by histopathological diagnosis or clinical follow-up data. By contrast, the PET/CT examination results revealed that 85 cases were true positives (a false positive foci was diagnosed in one of the patients), 18 were true negatives and 2 were false negatives. Correspondingly, the sensitivity and degree of accuracy were 97.7 and 97.1%, respectively. The detection rates of PET/CT for the recurrence and metastases were 85.3% in the CEA-positive group and 75.7% in the CEA-negative group. No significant differences were observed between the two groups. Overall, CEA levels do not help improve the detection rate of PET/CT in the recurrence and metastasis of CRC. PET/CT imaging has a high sensitivity and degree of accuracy in detecting recurrence and metastasis following CRC surgery. Therefore, this method is ideal for monitoring relapsed and metastatic foci of post-operative colon cancer cases.

Transarterial chemoembolization combined with sorafenib for advanced hepatocellular carcinoma

Sorafenib has been demonstrated to improve survival rate in patients with advanced hepatocellular carcinoma (HCC); however, the survival benefit remains modest and the response rates remain poor. Transarterial chemoembolization (TACE) may be used for the treatment of advanced HCC with well-preserved liver function and has a high local tumor control rate. We hypothesized that patients with advanced HCC may benefit from the combination of sorafenib with TACE. A retrospective study was conducted involving patients with advanced HCC, who had received at least one TACE session. Patients subsequently received 400 mg sorafenib twice per day and were monitored monthly. A dose reduction from 400 to 200 mg of sorafenib twice per day was permitted. The overall survival and side effects were subsequently followed up. In total, 38 patients were included from April 1st, 2009 to March 31st, 2012. All patients were treated with sorafenib after TACE was performed. As of March 31st, 2013, seven patients remained on sorafenib, and were censored at that time point. The median overall survival time was 12 months (95% confidence interval, 6.3-17.7 months). The sorafenib dose was reduced temporarily in 32 patients (84.2%). The most common toxicities were dermatological adverse effects (94.7%), diarrhea (63.2%) and alopecia (26.3%). The survival benefit of sorafenib combined with TACE for advanced HCC is promising, with no intolerable adverse events, provided that dose adjustment is permitted.

Efficacy of Sorafenib for Advanced Hepatocellular Carcinoma and Prognostic Factors

BACKGROUND/AIMS

Sorafenib, a drug that inhibits Raf serine/threonine kinases mediating cell proliferation and receptor tyrosine kinases involved in angiogenesis, is approved for treatment of advanced hepatocellular carcinoma. The study aims to evaluate the efficacy and analyze the prognostic factors of sorafenib treatment in patients with advanced hepatocellular carcinoma (HCC).

METHODOLOGY

Consecutive cases of HCC were treated with sorafenib (400 mg, Bid). Baseline clinical parameters, adverse events and survival were collected.

RESULTS

A total of 60 patients received sorafenib and transarterial therapy. There was no CR; 2 (3.3%) patients achieved partial response, but 30 patients (50.0%) achieved stable disease. The median follow-up time was 16 months. The median OS and median TTP were 13.6 months and 4.4 months respectively. The common adverse events were dermal reaction (60.0%, 36/60), diarrhea (46.7.0%, 28/60), hypertension (5.0%, 3/60), hair loss (16.7%, 10/60), myelosuppression (20.0%, 12/60), and liver dysfunction (25.0%, 15/60). In most patients, these side effects were mild-to-moderate, and alleviated remarkably after symptomatic treatment. The patients with lower tumor burden and without extrahepatic spread had better prognosis.

CONCLUSIONS

Soafenib is effective for unresectable primary HCC with tolerable toxicity. Tumor stage is a predominant prognostic factor.

Hepatocellular carcinoma metastasis to the lacrimal gland: A case report

Hepatocellular carcinoma (HCC) is a globally common neoplasm, with regional metastasis associated with >50% of the tumors. Extrahepatic metastasis is also common, with the lungs, diaphragm, abdominal lymph nodes and bone being the most frequently affected regions. However, to the best of our knowledge, HCC metastasis to the lacrimal gland has not been reported in the literature. Only one case of metastasis to the lacrimal sac from a renal cell carcinoma has been reported. The current study presents the case of a 56-year-old male with ocular symptoms who was eventually diagnosed with HCC. The therapeutic alternatives for such cases are also discussed according to the reviewed literature. Clinicians should be watchful for the appearance of tumors in the lacrimal gland in patients with a history of malignancy.

miR-146a G>C polymorphisms and risk of hepatocellular carcinoma in a Chinese population

MicroRNAs (miRNAs) are thought to have a role in cancer development. We investigated the association among miR-146a G>C genetic variations, hepatitis B (HBV), and C (HCV) infection, and risk of hepatocellular carcinoma (HCC). Unconditional logistical regression analysis suggested that the miR-146a GG genotype and G allele carried a 2.10- (95 % confidence interval (CI)=1.03-4.37) and 1.42-fold (95 % CI=1.07-1.92) increased HCC risk, respectively. HBV-positive subjects carrying the miR-146a GG genotype (odds ratio (OR)=2.95, 95 % CI=1.31-6.81) and G allele (OR=1.65, 95 % CI=1.15-2.58) had an increased risk of HCC. However, the miR-146a GG genotype and G allele did not carry a significantly enhanced risk of HCC in either hepatitis-negative or HCV-infected subjects. miR-146a G>C polymorphisms appear to influence susceptibility to HCC, especially in HBV-infected patients.

Ectopic hair cell-like cell induction by Math1 mainly involves direct transdifferentiation in neonatal mammalian cochlea

Math1, also known as Atoh1, is a basic helix-loop-helix transcription factor that plays a key role in hair cells (HCs) development. Previous studies have reported that Math1 gene transfer could induce the production of ectopic hair cell-like cells both in vitro and in vivo. Here, we focused on the mechanism of ectopic hair cell-like cellular differentiation from cells in the lateral epithelial ridge (LER) of cochlea with a human adenovirus serotype 5 (Ad5) vector encoding both Math1 and the reporter gene EGFP. Within the Ad5-EGFP-Math1 infection, hair-cell like cells could be detected in the LER. 5'-Bromo-2' deoxyuridine (BrdU) incorporation test results at different time points suggested that LER cells possessed high potential to proliferation, but they could not transdifferentiate into hair cells spontaneously. Almost all of Math1 induced hair cell-like cells were BrdU negative when BrdU incorporation occurred after Math1 expression. In conclusion, Math1 induced hair cell-like cells from LER cells mainly underwent direct trans-differentiation instead of mitosis of LER cells or newly hair cell-like cells.

[Transdifferention of some supporting cells in the cochlea induced by Ad5 atoh1/EGFP in the young adult guinea pigs]

OBJECTIVE

To explore whether the Ad5-atoh1/EGFP could transdifferent the supporting cells into the new hair cells in young adult guinea pigs cochlea in vivo.

METHOD

Twelve healthy pigmented guinea pigs weighted 200-250 g were included in this experiment. 5 ul of Ad5-E1/E3 defected-atoh1/EGFP were infused into the scala media through a hole made on the lateral wall of the cochlea. Six of the 12 animal were killed 2 weeks after the infusion operation. The others were killed 4 weeks after the operation. The whole mount of the basal membranes were directly observed under the fluorescence microscope for the expression of the EGFP (enhance green fluorescent protein) or for the expression of the hair cellspecific marker and nuclear after staining with myosin VIIa rabbit polyclonal antibody and Dapi dye.

RESULT

New cells with big nuclear, ellipse body and expressed with EGFP were found in the region near to the outmost row of the outer hair cells in 2 animal 2 weeks after the infusion. Moreover there were 3 animals with specific morphologic new cells in the location where ever been located by the outer hair cells and the region as 2 weeks animals 4 weeks after the infusion. Those cells were stained by myosin VIIa antibody.

CONCLUSION

Atoh1 gene could transdifferent some supporting cells in the basal membrane into hair cell like cells in young adult guinea pigs in vivo. These supporting cells locate in the region of outer hair cells and the basal membrane which do not belong to the region of outer hair cells.

[Analysis of BRAF mutation and extracellular regulated protein kinases activation in nasal mucosa melanomas]

OBJECTIVE

To determine the rate of BRAF gene mutation and the expression of activated extracellular regulated protein kinases (ERK) in nasal mucosa malignant melanomas and compare the results with those in cutaneous melanomas so as to explore the difference in the pathogenesis between nasal mucosa malignant melanomas and cutaneous melanomas.

METHODS

Twenty nasal mucosa melanomas samples were collected. Genomic DNA was extracted and the BRAF mutation detected by PCR (polymerase chain reaction) and direct sequencing analysis. Total protein was obtained and the activated ERK detected by Western blot.

RESULTS

BRAF mutation was detected in 5% (1/20) samples of all patients. The mutation rate was much lower than that in cutaneous melanomas. And phosphorylated ERK protein was detected in 60% (12/20). And the result was almost similar to that of cutaneous melanomas.

CONCLUSIONS

The high expression of activated ERK is not caused mainly by BRAF gene mutation in nasal mucosa malignant melanomas. The pathogenic pathways are different between nasal mucosa malignant melanomas and cutaneous melanomas.

Clinicopathological implications of tumour-associated macrophages and vascularization in sinonasal melanoma

This study investigated tumour-associated macrophages (TAMs) and their effects on tumour vascularization in sinonasal melanoma (SNM). Data on 45 patients with SNM undergoing surgery were reviewed retrospectively. Tumour sections were analysed immunohistochemically for TAMs, microvessels, lymph vessels, and vasculogenic mimicry in both intra- and peritumoural areas. The density of intratumoural TAMs was associated with tumour thickness and with overall survival in SNM stages I and II but there were no correlations between micro- or lymph vessel density and TAM infiltration. Greater TAM infiltration was observed in tumour tissues with vasculogenic mimicry although this was not statistically significant. These data suggest that high intratumoural TAM infiltration is associated with tumour aggressiveness and a poor prognosis for SNM, and that activation of macrophages can be polarized by different micro-environments. TAMs could be potential prognostic indicators for patients with SNM.

A six-generation Chinese family in haplogroup B4C1C exhibits high penetrance of 1555A > G-induced hearing Loss

Background

The 1555A > G mutation is the most common cause of aminoglycoside-induced and non-syndromic deafness. However, the variable clinical phenotype and incomplete penetrance of A1555G-induced hearing loss complicate our understanding of this mutation. Environmental factors, nuclear genes, mitochondrial haplotypes/variants and a possible threshold effect have been reported to may be involved in its manifestation.

Methods

Here, we performed a clinical, molecular, genetic and phylogenic analysis in a six-generation Chinese family.

Results

A clinical evaluation revealed that affected individuals without aminoglycoside exposure developed hearing loss extending gradually from 12000 Hz to 8000 Hz and then to 4000 Hz. Using pyrosequencing, we detected an identical homoplasmic 1555A > G mutation in all individuals except one. We did not find any correlation between the mutation load and the severity of hearing loss. T123N coexisted with the 1555A > G mutation in six affected subjects in our pedigree. Analysis of the complete mtDNA genome of this family revealed that this family belonged to haplotype B4C1C and exhibited high penetrance. Upon the inclusion of subjects that had been exposed to aminoglycosides, the penetrance of the hearing loss was 63.6%.; without exposure to aminoglycosides, it was 51.5%. This pedigree and another reported Chinese pedigree share the same haplotype (B4C1C) and lack functionally significant mitochondrial tRNA variants, but nevertheless they exhibit a different penetrance of hearing loss.

Conclusions

Our results imply that the factors responsible for the higher penetrance and variable expression of the deafness associated with the 1555A > G mutation in this pedigree may not be mtDNA haplotype/variants, but rather nuclear genes and/or aminoglycosides.

Three-dimensional reconstruction of C57BL/6 mouse inner ear during development

PURPOSE

To explore the three-dimensional (3-D) morphological characteristics of the complicated inner ear development of the C57BL/6 mouse.

METHODS

Specimens of C57BL/6 mouse embryos on days E7.5, E8.5, E9.5, E10.5, E11.5, E12.5 and E14.5 were collected and sectioned serially in this experiment. After hematoxylin and eosin staining, parts of the inner ear were pictured under the microscope with specific positional control. Using the protocol of 3D-DOCTOR software, we outlined the inner ear margin including the inner and extra face in different colors and put them into the 3-D program to reconstruct the 3-D model.

RESULTS

3-D models of the E9.5, E10.5, E11.5, E12.5 and E14.5 inner ear were obtained and proved to be fine. Different parts of the inner ear were shown clearly in different colors in the 3-D model and significant morphological changes of the inner ear were shown during development between E9.5 and E14.5.

CONCLUSION

The new technology of 3-D reconstruction is a useful and important tool to directly observe the complex development of the inner ear, and the development between E9.5 and E14.5 has been proved by the 3-D model to be the most complex and important period of the development of the C57BL/6 mouse inner ear.