Selective Phosphorylation of AMPA Receptor Contributes to the Network of Long-Term Potentiation in the Anterior Cingulate Cortex.

Phosphorylation of AMPA receptor GluA1 plays important roles in synaptic potentiation. Most previous studies have been performed in the hippocampus, while the roles of GluA1 phosphorylation in the cortex remain unknown. Here we investigated the involvement of the phosphorylation of GluA1 in the LTP in the anterior cingulate cortex (ACC) using mice with a GluA1 knock-in mutation at the PKA phosphorylation site serine 845 (s845A) or CaMKII/PKC phosphorylation site serine 831 (s831A). The network LTP, which is constructed by multiple recordings of LTP at different locations within the ACC, was also investigated. We found that the expression of LTP and network LTP was significantly impaired in the s845A mice, but not in the s831A mice. By contrast, basal synaptic transmission and NMDA receptor-mediated responses were not affected. Furthermore, to uncover potential information under the current acquired data, a new method for reconstruction and better visualization of the signals was developed to observe the spatial localizations and dynamic temporal changes of fEPSP signals and multiple LTP responses within the ACC circuit. Our results provide strong evidence that PKA phosphorylation of the GluA1 is important for the network LTP expression in the ACC.SIGNIFICANCE STATEMENT Previous studies have shown that PKA and PKC phosphorylation of AMPA receptor GluA1 plays critical roles in LTP in the hippocampus, while the roles of GluA1 phosphorylation in the cortex remain unknown. In the present study, by combining a 64-channel multielectrode system and a novel analysis and visualization method, we observed the accurate spatial localization and dynamic temporal changes of network fEPSP signals and LTP responses within the ACC circuit and found that PKA phosphorylation, but not PKC phosphorylation, of the GluA1 is required for LTP in the ACC.

MEKK4 Signaling Regulates Sensory Cell Development and Function in the Mouse Inner Ear.

Mechanosensory hair cells (HCs) residing in the inner ear are critical for hearing and balance. Precise coordination of proliferation, sensory specification, and differentiation during development is essential to ensure the correct patterning of HCs in the cochlear and vestibular epithelium. Recent studies have revealed that FGF20 signaling is vital for proper HC differentiation. However, the mechanisms by which FGF20 signaling promotes HC differentiation remain unknown. Here, we show that mitogen-activated protein 3 kinase 4 (MEKK4) expression is highly regulated during inner ear development and is critical to normal cytoarchitecture and function. Mice homozygous for a kinase-inactive MEKK4 mutation exhibit significant hearing loss. Lack of MEKK4 activity in vivo also leads to a significant reduction in the number of cochlear and vestibular HCs, suggesting that MEKK4 activity is essential for overall development of HCs within the inner ear. Furthermore, we show that loss of FGF20 signaling in vivo inhibits MEKK4 activity, whereas gain of Fgf20 function stimulates MEKK4 expression, suggesting that Fgf20 modulates MEKK4 activity to regulate cellular differentiation. Finally, we demonstrate, for the first time, that MEKK4 acts as a critical node to integrate FGF20-FGFR1 signaling responses to specifically influence HC development and that FGFR1 signaling through activation of MEKK4 is necessary for outer hair cell differentiation. Collectively, this study provides compelling evidence of an essential role for MEKK4 in inner ear morphogenesis and identifies the requirement of MEKK4 expression in regulating the specific response of FGFR1 during HC development and FGF20/FGFR1 signaling activated MEKK4 for normal sensory cell differentiation. SIGNIFICANCE STATEMENT: Sensory hair cells (HCs) are the mechanoreceptors within the inner ear responsible for our sense of hearing. HCs are formed before birth, and mammals lack the ability to restore the sensory deficits associated with their loss. In this study, we show, for the first time, that MEKK4 signaling is essential for the development of normal cytoarchitecture and hearing function as MEKK4 signaling-deficient mice exhibit a significant reduction of HCs and a hearing loss. We also identify MEKK4 as a critical hub kinase for FGF20-FGFR1 signaling to induce HC differentiation in the mammalian cochlea. These results reveal a new paradigm in the regulation of HC differentiation and provide significant new insights into the mechanism of Fgf signaling governing HC formation.

Traumatic noise activates Rho-family GTPases through transient cellular energy depletion.

Small GTPases mediate transmembrane signaling and regulate the actin cytoskeleton in eukaryotic cells. Here, we characterize the auditory pathology of adult male CBA/J mice exposed to traumatic noise (2-20 kHz; 106 dB; 2 h). Loss of outer hair cells was evident 1 h after noise exposure in the basal region of the cochlea and spread apically with time, leading to permanent threshold shifts of 35, 60, and 65 dB at 8, 16, and 32 kHz. Several biochemical and molecular changes correlated temporally with the loss of cells. Immediately after exposure, the concentration of ATP decreased in cochlear tissue and reached a minimum after 1 h while the immunofluorescent signal for p-AMPKα significantly increased in sensory hair cells at that time. Levels of active Rac1 increased, whereas those of active RhoA decreased significantly 1 h after noise attaining a plateau at 1-3 h; the formation of a RhoA-p140mDia complex was consistent with an activation of Rho GTPase pathways. Also at 1-3 h after exposure, the caspase-independent cell death marker, Endo G, translocated to the nuclei of outer hair cells. Finally, experiments with the inner ear HEI-OC1 cell line demonstrated that the energy-depleting agent oligomycin enhanced both Rac1 activity and cell death. The sum of the results suggests that traumatic noise induces transient cellular ATP depletion and activates Rho GTPase pathways, leading to death of outer hair cells in the cochlea.

Hierarchical Macroporous Agarose Materials with Polyethyleneimine-Assisted Multiple Boronate Affinity Binding Sites for the Separation of Neomycin.

Quantification of neomycin residues in food samples demands an efficient purification platform. Herein, hierarchical macroporous agarose monoliths with multiple boronate affinity sites were established for selective separation of neomycin. The silica core was synthesized by "one-step" Stöber procedures followed by modification with amino group and incorporation of polyethyleneimine. A versatile macroporous agarose monolith was prepared by emulsification strategies and functionalized with epoxy groups. After introducing polyethyleneimine-integrated silica nanoparticles onto the agarose monolith, fluorophenylboronic acids were immobilized. The physical and chemical characteristics of the composite monolith were analyzed systematically. After optimization, neomycin showed high binding ability of 23.69 mg/g, and the binding capacity can be manipulated by changing the pH and adding monosaccharides. The composite monolith was subsequently utilized to purify neomycin from the spiked model aquatic products followed by high-performance liquid chromatography analysis, which revealed a remarkable neomycin purification effect, indicating the great potential in the separation of neomycin from complicated aquatic products.

Causal effects of circulating vitamin levels on the risk of heart failure: a Mendelian randomization study.

BACKGROUND: Observational studies suggest inverse associations between serum vitamin levels and the risk of heart failure (HF). However, the causal effects of vitamins on HF have not been fully elucidated. Here, we conducted a Mendelian randomization (MR) study to investigate the causal associations between genetically determined vitamin levels and HF. METHODS: Genetic instrumental variables for circulating vitamin levels, including vitamins A, B, C, D, and E, which were assessed as either absolute or metabolite levels were obtained from public genome-wide association studies. Summary statistics for single-nucleotide-polymorphisms and HF associations were retrieved from the HERMES Consortium (47,309 cases and 930,014 controls) and FinnGen Study (30,098 cases and 229,612 controls). Two-sample MR analyses were implemented to assess the causality between vitamin levels and HF per outcome database, and the results were subsequently combined by meta-analysis. RESULTS: Our MR study did not find significant associations between genetically determined circulating vitamin levels and HF risk. For absolute vitamin levels, the odds ratio for HF ranged from 0.97 (95% confidence interval [CI]: 0.85-1.09, P = 0.41) for vitamin C to 1.05 (95% CI: 0.61-1.82, P = 0.85) for vitamin A. For vitamin metabolites, the odds ratio ranged between 0.94 (95% CI: 0.75-1.19, P = 0.62) for α-tocopherol and 1.11 (95% CI: 0.98-1.26, P = 0.09) for γ-tocopherol. CONCLUSION: Evidence from our study does not support the causal effects of circulating vitamin levels on HF. Therefore, there may be no direct beneficial effects of vitamin intake on the prevention of primary HF.

A novel mutation in COL1A1 causing osteogenesis imperfecta/hearing loss.

OBJECTIVES: To screen the COL1A1 and COL1A2 gene mutation sites in a family with type I osteogenesis imperfecta (OI)/hearing loss and analyze the characteristics and recovery of hearing loss in patients with osteogenesis imperfecta. METHODS: The basic clinical data of OI proband and her parents were collected, and the COL1A1 and COL1A2 genes were detected in peripheral blood by PCR amplification and generation Sanger sequencing. Literature of stapedial surgery in patients with osteogenesis imperfecta was collected. RESULTS: The heterozygous mutation of the 26 exon c.1922_1923 ins C in the OI progenitor COL1A1 gene led to the amino acid frameshift mutation of p.Pro 601FS, which was not detected in the phenotypic parents. The homozygous of exon 28 c.1782>G in COL1A2 was detected in the proband and her parents, resulting in changes in the protein p.Pro 549Ala. CONCLUSION: The clinical symptoms of the OI proband is caused by heterozygous mutation of the 26 exon c.1922_1923 ins C in COL1A1 gene. Stapedial surgery can provide short-term and long-term hearing benefits for OI patients with hearing loss. LEVEL OF EVIDENCE: Level 4.

Effect of treatment modality on the long-term survival of patients with early glottic squamous cancer: a retrospective cohort study based on the SEER database.

Background: The optimal treatment strategy for patients with early glottic (T1-2N0M0) squamous cancer remains unclear. Methods: A retrospective population-based analysis was performed using the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was used to balance treatment arms, and Cox regression analysis was used to determine prognostic factors for survival. Kaplan-Meier analysis, log-rank tests, and competing risk analysis were used to compare survival outcomes between treatment modalities (surgery vs. radiotherapy). Results: Among the 3,994 eligible patients in this study, surgery was associated with improved cancer-specific survival (CSS) and overall survival (OS) compared with radiotherapy (log-rank test, P<0.05). This survival trend favoring surgery was consistent in the T1a, well/moderately differentiated grade, male, and all age subgroups. However, after the baseline characteristics were balanced with PSM, the survival outcomes (CSS and OS) did not differ significantly between the surgery and radiotherapy groups. Interestingly, surgery was associated with a 39% reduced risk of cancer-related death compared with radiotherapy in patients aged ≥70 years (hazard ratio 0.61; 95% CI: 0.43-0.87; P=0.006). However, this survival trend favoring surgery was not observed in younger patients (age <70 years), T stage subgroups, male or female subgroups, or in any of the pathological grade subgroups. Conclusions: In patients with early glottic squamous cell carcinoma undergoing surgery or radiotherapy, there is no sufficient evidence favoring one method over another in terms of survival. However, surgery is recommended in patients aged ≥70 years because, in this group, it was associated with improved survival outcomes compared with radiotherapy.

Primary Middle Ear Meningioma with Intact Tympanic Membrane: A Case Report and Literature Review.

Primary ectopic meningioma of the middle ear is relatively rare in clinical practice. It is often difficult to distinguish it from chronic otitis media or otitis media with effusion due to its similar and atypical clinical symptoms. We report a case of epithelial tympanic ectopic meningioma with the main complaints of otalgia, aural fullness, and hearing loss. It was accidentally discovered during tympanotomy due to the symptoms of recurring refractory secretory otitis media. This article briefly reviews the relevant literature in recent years, summarizes the characteristics of primary ectopic tympanic meningioma with intact tympanic membrane, and emphasizes the diagnosis and treatment strategy of the middle ear mass.

Treatment With Calcineurin Inhibitor FK506 Attenuates Noise-Induced Hearing Loss.

Attenuation of noise-induced hair cell loss and noise-induced hearing loss (NIHL) by treatment with FK506 (tacrolimus), a calcineurin (CaN/PP2B) inhibitor used clinically as an immunosuppressant, has been previously reported, but the downstream mechanisms of FK506-attenuated NIHL remain unknown. Here we showed that CaN immunolabeling in outer hair cells (OHCs) and nuclear factor of activated T-cells isoform c4 (NFATc4/NFAT3) in OHC nuclei are significantly increased after moderate noise exposure in adult CBA/J mice. Consequently, treatment with FK506 significantly reduces moderate-noise-induced loss of OHCs and NIHL. Furthermore, induction of reactive oxygen species (ROS) by moderate noise was significantly diminished by treatment with FK506. In agreement with our previous finding that autophagy marker microtubule-associated protein light chain 3B (LC3B) does not change in OHCs under conditions of moderate-noise-induced permanent threshold shifts, treatment with FK506 increases LC3B immunolabeling in OHCs after exposure to moderate noise. Additionally, prevention of NIHL by treatment with FK506 was partially abolished by pretreatment with LC3B small interfering RNA. Taken together, these results indicate that attenuation of moderate-noise-induced OHC loss and hearing loss by FK506 treatment occurs not only via inhibition of CaN activity but also through inhibition of ROS and activation of autophagy.

Narrow-band red emitting oxonitridosilicate phosphor La4-xSr2+xSi5N12-xOx:Pr3+ (x≈ 1.69).

The new oxonitridosilicates Ln4-xSr2+xSi5N12-xOx (Ln = La, Ce) were synthesized by high temperature solid-state reactions. The crystal structures were solved and refined from both single-crystal and powder X-ray diffraction data. These oxonitridosilicate compounds crystallize in the monoclinic space group P21/n (no. 14) and exhibit a double-layer structure made up of corner-sharing Si(O/N)4 tetrahedra. When excited with near-UV and blue light, the Pr3+ doped La2.31Sr3.69Si5N10.31O1.69 phosphor shows a narrow-band red emission peaking at 625 nm with a full width at half-maximum of 40 nm.

Iron-chelated thermoresponsive polymer brushes on bismuth titanate nanosheets for metal affinity separation of phosphoproteins.

Separation of phosphoproteins plays an important role for identification of biomarkers in life science. In this work, bismuth titanate supported, iron-chelated thermoresponsive polymer brushes were prepared for selective separation of phosphoproteins. The iron-chelated thermoresponsive polymer brushes were synthesized by surface-initiated atom transfer radical polymerization of N-isopropylacrylamide and glycidyl methacrylate, followed by a ring opening reaction of epoxy group, and chelation of the obtained cis-diols with Fe3+ ions. The composite material was characterized to determine the size and thickness, the content of the organic polymer and the metal loading. The bismuth titanate supported, iron-chelated thermoresponsive polymer brushes showed selective binding for phosphoproteins in the presence of abundant interfering proteins, and a high binding capacity for phosphoproteins by virtue of the metal affinity between the metal ions on the polymer brushes and the phosphate groups in the phosphoproteins (664 mg ß-Casein per g sorbent). The thermoresponsive property of the polymer brushes made it possible to adjust phosphoprotein binding by changing temperature. Finally, separation of phosphoproteins from a complex biological sample (i.e. milk) was demonstrated using the nanosheet-supported thermoresponsive polymer brushes.

A novel mutation in COL1A1 causing osteogenesis imperfecta/hearing loss

Abstract Objectives: To screen the COL1A1 and COL1A2 gene mutation sites in a family with type I osteogenesis imperfecta (OI)/hearing loss and analyze the characteristics and recovery of hearing loss in patients with osteogenesis imperfecta. Methods: The basic clinical data of Ol proband and her parents were collected, and the COL1A1 and COL1A2 genes were detected in peripheral blood by PCR amplification and generation Sanger sequencing. Literature of stapedial surgery in patients with osteogenesis imperfecta was collected. Results: The heterozygous mutation of the 26 exon c.1922_1923 ins C in the Ol progenitor COL1A1 gene led to the amino acid frameshift mutation of p.Pro 601FS, which was not detected in the phenotypic parents. The homozygous of exon 28 c.1782>G in COL1A2 was detected in the proband and her parents, resulting in changes in the protein p.Pro 549Ala. Conclusion: The clinical symptoms of the Ol proband is caused by heterozygous mutation of the 26 exon c.1922_1923 ins C in COL1A1 gene. Stapedial surgery can provide short-term and long-term hearing benefits for Ol patients with hearing loss. Level of evidence: Level 4.

Narrow-band blue emitting nitridomagnesosilicate phosphor Sr8Mg7Si9N22:Eu2+ for phosphor-converted LEDs.

We report a novel narrow-band blue emitting phosphor Sr7.92Mg7Si9N22:0.08Eu2+. The crystal structure of Sr8Mg7Si9N22 is composed of corner-sharing and edge-sharing [SiN4] tetrahedra and distorted square-pyramid [MgN5] polyhedra. Under 350 nm excitation, Eu2+ doped Sr8Mg7Si9N22 emits narrow-band blue light with maximum intensity at 450 nm and a fwhm of 38 nm.

Intra-tympanic delivery of short interfering RNA into the adult mouse cochlea.

Trans-tympanic injection into the middle ear has long been the standard for local delivery of compounds in experimental studies. Here we demonstrate the advantages of the novel method of intra-tympanic injection through the otic bone for the delivery of compounds or siRNA into the adult mouse cochlea. First, a fluorescently-conjugated scrambled siRNA probe was applied via intra-tympanic injection into the middle ear cavity and was detected in sensory hair cells and nerve fibers as early as 6 h after the injection. The fluorescent probe was also detected in other cells of the organ of Corti, the lateral wall, and in spiral ganglion cells 48 h after the injection. Furthermore, intra-tympanic delivery of Nox3 siRNA successfully reduced immunofluorescence associated with Nox3 in outer hair cells 72 h after injection by 20%. Drug or siRNA delivery via intra-tympanic injection does not compromise the tympanic membrane or interfere with noise-induced hearing loss, while trans-tympanic injections significantly altered the cochlear response to noise exposure. In summary, intra-tympanic injection through the otic bone into the middle ear cavity provides a promising approach for delivery of compounds or siRNA to cochlear hair cells of adult mice, relevant for the study of mechanisms underlying inner ear insults and, specifically, noise-induced hearing loss.

Mitochondrial peroxiredoxin 3 regulates sensory cell survival in the cochlea.

This study delineates the role of peroxiredoxin 3 (Prx3) in hair cell death induced by several etiologies of acquired hearing loss (noise trauma, aminoglycoside treatment, age). In vivo, Prx3 transiently increased in mouse cochlear hair cells after traumatic noise exposure, kanamycin treatment, or with progressing age before any cell loss occurred; when Prx3 declined, hair cell loss began. Maintenance of high Prx3 levels via treatment with the radical scavenger 2,3-dihydroxybenzoate prevented kanamycin-induced hair cell death. Conversely, reducing Prx3 levels with Prx3 siRNA increased the severity of noise-induced trauma. In mouse organ of Corti explants, reactive oxygen species and levels of Prx3 mRNA and protein increased concomitantly at early times of drug challenge. When Prx3 levels declined after prolonged treatment, hair cells began to die. The radical scavenger p-phenylenediamine maintained Prx3 levels and attenuated gentamicin-induced hair cell death. Our results suggest that Prx3 is up-regulated in response to oxidative stress and that maintenance of Prx3 levels in hair cells is a critical factor in their susceptibility to acquired hearing loss.

Tumor necrosis factor-alpha-mutant mice exhibit high frequency hearing loss.

Exogenous tumor necrosis factor-alpha (TNF-α) plays a role in auditory hair cell death by altering the expression of apoptosis-related genes in response to noxious stimuli. Little is known, however, about the function of TNF-α in normal hair cell physiology. We, therefore, investigated the cochlear morphology and auditory function of TNF-α-deficient mice. Auditory evoked brainstem response showed significantly higher thresholds, especially at higher frequencies, in 1-month-old TNF-α(-/-) mice as compared to TNF-α(+/-) and wild type (WT); hearing loss did not progress further from 1 to 4 months of age. There was no difference in the gross morphology of the organ of Corti, lateral wall, and spiral ganglion cells in TNF-α(-/-) mice compared to WT mice at 4 months of age, nor were there differences in the anatomy of the auditory ossicles. Outer hair cells were completely intact in surface preparations of the organ of Corti of TNF-α(-/-) mice, and synaptic ribbon counts of TNF-α(-/-) and WT mice at 4 months of age were similar. Reduced amplitudes of distortion product otoacoustic emissions, however, indicated dysfunction of outer hair cells in TNF-α(-/-) mice. Scanning electron microscopy revealed that stereocilia were sporadically absent in the basal turn and distorted in the middle turn. In summary, our results demonstrate that TNF-α-mutant mice exhibit early hearing loss, especially at higher frequencies, and that loss or malformation of the stereocilia of outer hair cells appears to be a contributing factor.

Circulating MicroRNAs as potential risk biomarkers for hematoma enlargement after intracerebral hemorrhage.

BACKGROUND AND PURPOSE: MicroRNAs have recently been shown to regulate the downstream bioprocesses of intracerebral hemorrhage. The aim of this study was to investigate whether miRNAs can be used as biomarkers to predict secondary hematoma enlargement (HE) in patients with ICH. METHODS: Consecutively, 79 ICH patients admitted within 6 h of symptom onset and 30 healthy individuals were enrolled in this study. Whole-genome miRNA expression profiles were generated in 32 patients (HE/non-HE: 14/18). Representative differentially expressed miRNAs were measured in all cases (HE/non-HE: 30/49) and normal controls (n = 30) by real-time PCR. RESULTS: Thirty miRNAs showed differential expressions in the plasma samples from patients with HE as compared with the non-HE controls. Compared to the hierarchical cluster analysis with all probes on microarray, all patients were separated into two main branches with only four exceptions by 30 differentially expressed miRNAs, improving the overall accuracy from 47.62 to 77.78% in the HE and 72.73 to 100% in the non-HE group. Further support vector machine (SVM) test can discriminate the two groups with 100% accuracy with 10 differentially expressed miRNAs. CONCLUSIONS: We demonstrated that multiple miRNAs are differentially expressed in the plasma of ICH patients with or without HE and may serve as circulating biomarkers for predicting HE after ICH.

[A pilot study on the diagnosis of laryngopharyngeal reflux diseases].

OBJECTIVE: To study the value of the reflux symptom index (RSI) and reflux finding score (RFS) in laryngopharyngeal reflux disease (LPRD). METHODS: Twenty-five patients with RSI scores > 13 or RFS scores > 7 and sixteen patients with RSI scores > 13 and RFS scores > 7 were suspected as LPRD. Forty one patients with the RSI scores > 13 and/or RFS scores > 7 were suspected as LPRD, 15 patients with the RSI scores 13 and RFS scores > 7 (Kappa = 0.55, u = 3.06, P < 0.01). There was a significant decreasing in RSI and RFS scoring in patients after anti-acid treatment for 3 months (t(RSI) = 8.838, P(RSI) = 0.000; t(RFS) = 5.695, P(RFS) = 0.000). CONCLUSIONS: The RSI and RFS can be used as screening tool for laryngopharyngeal reflux diseases and as a simple method for evaluating the effectiveness of treatment.

[Cochlear reimplantation].

OBJECTIVE: To analyze retrospectively the outcome of 6 cases of cochlear reimplantation to summarize its experience. METHODS: The operation method of cochlear reimplantation was similar to routine cochlear implantation. A "H" incision for the muscle-periosteum was used to shorten the operation time. RESULTS: Of all the cases, the electrodes are successfully and totally inserted into the cochlea. The causes for revision are different. The electrode was found to be not in the proper situ of the cochlea after the first operation in one patient. The out part was ruptured because of trauma in another patient. The causes of the other four patients were unknown. CONCLUSIONS: The incision should not be too small. The control electrode should be put beneath the periosteum. The site used to fix up the out part need be burnished. Unabsorbable suture should do not be used. It is important to insert the new electrode quickly after drawing the old one out. The time to accommodate the new electrode often needs 3-4 weeks.