Loss of Pax3 causes reduction of melanocytes in the developing mouse cochlea.

Cochlear melanocytes are intermediate cells in the stria vascularis that generate endocochlear potentials required for auditory function. Human PAX3 mutations cause Waardenburg syndrome and abnormalities of skin and retinal melanocytes, manifested as congenital hearing loss (~ 70%) and hypopigmentation of skin, hair and eyes. However, the underlying mechanism of hearing loss remains unclear. Cochlear melanocytes in the stria vascularis originated from Pax3-traced melanoblasts and Plp1-traced Schwann cell precursors, both of which derive from neural crest cells. Here, using a Pax3-Cre knock-in mouse that allows lineage tracing of Pax3-expressing cells and disruption of Pax3, we found that Pax3 deficiency causes foreshortened cochlea, malformed vestibular apparatus, and neural tube defects. Lineage tracing and in situ hybridization show that Pax3+ derivatives contribute to S100+, Kir4.1+ and Dct+ melanocytes (intermediate cells) in the developing stria vascularis, all of which are significantly diminished in Pax3 mutant animals. Taken together, these results suggest that Pax3 is required for the development of neural crest cell-derived cochlear melanocytes, whose absence may contribute to congenital hearing loss of Waardenburg syndrome in humans.

Clinical characteristics in Japanese patients with chronic rhinosinusitis who underwent endoscopic sinus surgery.

OBJECTIVE: There is heterogeneity in the pathophysiology of chronic rhinosinusitis (CRS). Obtaining a detailed understanding of patient profiles in specific regions can provide valuable information not only for clinical practice but also future research plans. The aim of this study was to investigate the characteristics of patients who underwent endoscopic sinus surgery (ESS) for CRS. METHODS: This retrospective, single-center study examined the features of 453 patients with CRS who underwent ESS in the Tokyo area of Japan. The study evaluated various factors in patients with CRS including sex and age, the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) score, the recurrence rate of CRS, comorbidities of asthma and/or allergic diseases, and IgE sensitization to 12 inhaled allergens. RESULTS: Age-related declines in the sensitization rate to inhaled allergens were observed, and the most notable age-related decrease in specific IgE antibodies was observed for house dust mites (HDM) (p = 8.3 × 10-7). Sensitization to HDM, cat dander, and various types of fungi, including Aspergillus, was frequently observed in the CRS with asthma group, with rates of 54%, 17%, and 17%, respectively. We found that 23% of the patients had recurrence. In the recurrence group, the positive rates of specific IgE antibodies for birch and cat dander were significantly higher than in the no recurrence group. Bronchial asthma was identified as an important factor for recurrence. Among male patients, the recurrence group was younger than the no-recurrence group (p = 0.0032). Severe eosinophilic CRS (ECRS) showed early recurrence after surgery, with over the half of the patients experiencing at least one recurrence within 2 years post-surgery. Among patients with ECRS, the recurrence rate for females was 1.92 times higher than for males. CONCLUSION: Our study revealed the influences of age and sex on various clinical phenotypes of CRS patients undergoing ESS. There was a high sensitization rate to cat dander in both the recurrence and asthma groups. Further research on diverse disease etiologies is necessary to improve therapeutic strategies for patients with CRS.

Pax3 deficiency diminishes melanocytes in the developing mouse cochlea.

Cochlear melanocytes are intermediate cells in the stria vascularis that generate endocochlear potentials required for auditory function. Human PAX3 mutations cause Waardenburg syndrome and abnormalities of melanocytes, manifested as congenital hearing loss and hypopigmentation of skin, hair and eyes. However, the underlying mechanism of hearing loss remains unclear. During development, cochlear melanocytes in the stria vascularis are dually derived from Pax3-Cre+ melanoblasts migrating from neuroepithelial cells including neural crest cells and Plp1+ Schwann cell precursors originated from also neural crest cells, differentiating in a basal-apical manner. Here, using a Pax3-Cre mouse line, we found that Pax3 deficiency causes foreshortened cochlea, malformed vestibular apparatus, and neural tube defects. Lineage tracing and in situ hybridization show that Pax3-Cre derivatives contribute to S100+ , Kir4.1+ and Dct+ melanocytes (intermediate cells) in the developing stria vascularis, all significantly diminished in Pax3 mutant animals. Taken together, these results suggest that Pax3 is required for the development of neural crest cell-derived cochlear melanocytes, whose absence may contribute to congenital hearing loss of Waardenburg syndrome in human.

A case of fungal otitis externa caused by coinfection of Candida auris and Aspergillus flavus.

Fungal otitis externa is a disease encountered occasionally and is caused mostly by Aspergillus or Candida spp. We report a woman with fungal otitis externa who also had typical findings in the external auditory canal. The results of a culture showed coinfection with Candida auris and Aspergillus flavus. Identification of both species was performed by sequencing analysis of the 26S rDNA (D1/D2) and ß-tubulin regions. Additionally, the newly developed CHROMagar™ Candida Plus medium was a useful tool for the easy and rapid identification of C. auris. To the best of our knowledge, this is the first report of fungal otitis externa caused by coinfection with C. auris and A. flavus. This case showed good susceptibility to many antifungal drugs and fortunately had a good clinical course with 1% bifonazole cream, which was applied to the fungal coinfection. Notably, C. auris is a multidrug-resistant yeast-like fungus. The increase in drug-resistant fungi and co-infections caused by these pathogens can make the diagnosis and treatment more complex and difficult. To solve these problems, performing rapid and accurate identification and susceptibility testing using chromogenic medium and molecular biological analysis would be useful.

Real-world burden and treatment of chronic rhinosinusitis in Japan: A retrospective claims database analysis.

Objectives: Chronic rhinosinusitis (CRS) is a heterogeneous disease, which can be subdivided into CRS with (CRSwNP) or without (CRSsNP) nasal polyps. An intractable form of CRSwNP that is associated with an eosinophil-dominant inflammatory cell infiltration (eosinophilic CRS) has become more prevalent in Japan. There is currently limited information on the burden of CRS in Japan and treatment approaches used in real-world practice. Methods: This retrospective, observational, comparative cohort study used information from the Japanese JMDC insurance claims database (study period April 1, 2015, to March 31, 2020). A CRS cohort was identified and matched with a control group without CRS. The primary objective was to clarify disease burden and treatment approaches by comparing comorbidities, healthcare resource utilization (HRU), and drug prescriptions in the CRS and non-CRS groups. Results: In total, 23,256 individuals with CRS (1762 with CRSwNP and 21,494 with CRSsNP) were matched with 23,256 controls. The mean age was 45 years and the majority of individuals were male (57%). Individuals with CRS had a higher disease burden than controls, with more frequent comorbidities (particularly, type 2 inflammatory disease [e.g., allergic rhinitis and asthma], and those caused by systemic corticosteroids [SCS]), and higher HRU (including outpatient visits, laboratory examinations and surgical procedures). Further, individuals with CRS were prescribed more medications, both for CRS (including SCS) and non-CRS conditions, than controls. Conclusion: In Japan, CRS is associated with a high disease burden, and multiple treatment approaches are used in affected individuals, including long-term SCS, which is generally not recommended. Level of Evidence: 3.

Analysis of the epidermal growth factor receptor/phosphoinositide-dependent protein kinase-1 axis in tumor of the external auditory canal in response to epidermal growth factor stimulation.

Objectives: The epidermal growth factor receptor (EGFR) is related to the invasion and metastasis of external auditory canal (EAC) squamous cell carcinoma (SCC). The phosphoinositide-dependent protein kinase-1 (PDPK1) accelerates tumor cell growth through anti-apoptotic signaling under the influence of downstream EGFR-mediated signaling pathways. In this study, we investigated the EGFR/PDPK1 axis in the EAC under EGF stimulation. Methods: We confirmed EGFR and PDPK1 expression in human EACSCC specimens immunohistochemically. We next transfected the EGF expression vector in the mouse EAC and then conducted a PDPK1 inhibitory experiment. Immunohistochemical analysis was performed in the mouse EAC, using anti-EGF, anti-EGFR, anti-PDPK1, and anti-Ki67 antibodies. Immunohistochemical analysis of cleaved caspase-3 and terminal deoxy(d)-UTP nick end labeling (TUNEL) detection assays were also performed for the assessment of apoptosis in the inhibitory experiment. Results: Immunohistochemical analysis revealed overexpression and colocalization of EGFR and PDPK1 in human EACSCC specimens. The growth of a protuberant tumor was observed in the mouse EAC in which EGF expression vector was transfected, and EGF, EGFR, PDPK1, and Ki67 labeling indexes (LIs) were significantly increased. PDPK1 inhibition then induced normal epithelial appearance in the EAC. Moreover, EGF, EGFR, PDPK1, and Ki67 LIs were decreased, and cleaved caspase-3 and TUNEL LIs were increased in the EAC. Conclusion: We demonstrated the possibility that PDPK1 plays an important role in EACSCC.Level of Evidence: NA.

A Phase II, Multicenter, Randomized, Placebo-Controlled Study of Benralizumab, a Humanized Anti-IL-5R Alpha Monoclonal Antibody, in Patients With Eosinophilic Chronic Rhinosinusitis.

BACKGROUND: Strong eosinophil infiltration in chronic rhinosinusitis with nasal polyp (CRSwNP) is highly associated with recalcitrance and higher nasal polyp recurrence rate after surgery. The prevalence of eosinophilic CRSwNP (ECRS) is increasing in Asian countries including Japan. Benralizumab is a humanized anti-IL-5R alpha monoclonal antibody that depletes eosinophils by antibody-dependent cell-mediated cytotoxicity. OBJECTIVE: To assess the efficacy and safety of benralizumab in patients with ECRS. METHODS: This phase II, randomized, double-blind, placebo-controlled study was conducted in Japan. Patients were randomized 1:2:2 to placebo, a single administration of benralizumab 30 mg, or benralizumab 30 mg every 4 weeks (q4w) for a total of three doses. The primary endpoint was the change in nasal polyp score from baseline at Week 12. RESULTS: Overall, 56 patients were enrolled (placebo, n = 11; benralizumab single dose, n = 22; benralizumab q4w, n = 23). Although the mean total nasal polyp score began to decrease after the initiation of benralizumab treatment, there were no statistically significant differences in change in nasal polyp score from baseline at Week 12 between benralizumab and placebo (placebo, -0.5 ± 0.8; benralizumab single, -0.3 ± 0.8; benralizumab q4w, -0.5 ± 1.5). Post-hoc analysis showed that the administration of benralizumab decreased nasal polyp scores ≥2 points in 42.2% of ECRS patients and that patients with high blood eosinophil levels had a greater tendency to respond to benralizumab treatment. The safety profile was similar to that in previous studies and no unexpected adverse events were noted. CONCLUSION: Although benralizumab did not meet the primary efficacy endpoint, reductions of nasal polyp scores were seen in the benralizumab group compared with the placebo group over the whole study period, especially in patients with high levels of blood eosinophils.

Regulation of DNA methylation levels in the process of oral mucosal regeneration in a rat oral ulcer model.

DNA methylation is an important epigenetic mechanism for cellular maintenance. However, the methylation pattern and the key molecule regulated epigenetically in oral mucosal regeneration is unclear. In this study, we generated a rat oral ulcer model and investigated the cell proliferative activities and DNA methylation patterns immunohistochemically. We also performed immunohistochemical analysis of a regulator of epithelial stem/progenitor cell differentiation in the rat model. We demonstrated immunohistochemistry using antibodies for the molecules as follows: Ki-67, a marker of cellular proliferation; 5-methylcytosine (5-mC), a marker of DNA methylation; 5-hydroxymethylcytosine (5-hmC), a marker of DNA demethylation; Dnmt1, a maintenance DNA methyltransferase; Dnmt3a and Dnmt3b, de novo DNA methyltransferases; and Wnt5a, a regulator of stem/progenitor cell differentiation. In this model, re-epithelialization was completed at Day 4 after ulceration. Regenerating mucosal hypertrophy reached a peak at Day 5 and appeared normal at Day 14. Ki-67-positive cells increased at Day 2 and returned to normal at Day 6 after ulceration. The ratio of the expression level of 5-mC to 5-hmC declined at Day 5 and returned to normal at Day 6. The expression level of Dnmt1 had not changed compared to the normal control at every time point. On the other hand, the expression levels of Dnmt3a and Dnmt3b had decreased significantly at Day 5 and returned to normal at Day 6. Moreover, Wnt5a-positive cells increased at Day 5. In conclusion, oral mucosal regeneration was strictly regulated by DNA methylation. Moreover, Wnt5a might play a critical role in oral mucosal regeneration.

JESREC score and mucosal eosinophilia can predict endotypes of chronic rhinosinusitis with nasal polyps.

OBJECTIVE: Recently, JESREC score and mucosal eosinophil count have been used to diagnose eosinophilic chronic rhinosinusitis (ECRS) in Japan. However, it remains unknown whether the subtypes of CRS diagnosed by these criteria have different endotypes. In the present study, we investigated whether JESREC score and mucosal eosinophil count were appropriate for classification of CRS subgroups into endotypes. METHODS: A cross-sectional study involving 71 consecutive patients with CRS with nasal polyps (CRSwNP) and 13 control patients was performed. Nasal polyp tissues from CRSwNP patients and uncinate process tissues from control patients were collected for analysis of inflammatory cells by immunohistochemistry and measurement of cytokines and chemokines by ELISA and quantitative real-time PCR. We compared the differences between subtypes according to JESREC score and mucosal eosinophil count and investigated the subgroups with different endotypes by cluster analysis and principal component analysis. RESULTS: In the 71 CRSwNP patients, 9 patients had JESREC score <11 and mucosal eosinophil count <70/HPF (Group A), 20 patients had JESREC score ≥11 and mucosal eosinophil count <70/HPF (Group C), and 42 patients had JESREC score ≥11 and mucosal eosinophil count ≥70/high-power field (HPF) (Group D). Semiquantitative analysis of inflammatory cells showed that eosinophils, neutrophils, macrophages, mast cells, and basophils differed significantly between the subgroups. At the mRNA level, CLC, IL5, IL13, CCL11, CCL24, CCL26, POSTN, CSF3, and IL8 showed significant differences. At the protein level, eotaxin-2/CCL24, eotaxin-3/CCL26, and G-CSF had significant differences. Cluster analysis using gene expression levels in 55 CRS patients and 11 control patients revealed that the patients could be classified into five clusters. Cluster 1 (n=27) contained all patients with Group D. Cluster 2 (n=11) comprised all control patients. Cluster 3 (n=4) included mixed subtypes: one with Group A and three with Group D. Cluster 4 (n=7) and Cluster 5 (n=17) contained all patients with Groups A and C, respectively. Furthermore, the principal component analysis revealed that the subtypes had different characteristics. CONCLUSION: CRS subtypes based on JESREC score and mucosal eosinophil count showed different inflammatory patterns, and unsupervised statistical analyses supported the classification that can predict endotypes. From these results, we concluded that the classification based on JESREC score and mucosal eosinophil count was useful for predicting CRS endotypes.

Distinct gene expression profiles and regulation networks of nasal polyps in eosinophilic and non-eosinophilic chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is known to have 2 phenotypes in East Asia. Eosinophilic CRSwNP (ECRSwNP), defined as tissue eosinophilia and easily recurrent, is distinguished from other non-eosinophilic CRSwNP (NECRSwNP) types. However, the pathogenesis of each remains unclear. METHODS: Nasal polyp tissues from ECRS (ECRSwNP) and NECRS (NECRSwNP) patients were obtained, and their comprehensive gene expression profiles were investigated by microarray analysis. Bioinformatics approaches (eg, Ingenuity Pathway Analysis [IPA]) were used to interrogate the data sets. RESULTS: Hierarchical clustering and principal component analysis (PCA) collectively showed that ECRSwNP and NECRSwNP had distinct gene expression patterns. Of note, these genes could be divided into 8 distinctive clusters having different expression patterns and functions. Upstream Regulator Analysis revealed that not only T-helper 2 (Th2) and the eosinophilia-related molecules (interleukin 4 [IL4], IL5, and colony stimulating factor 2 [CSF2]) reported so far, but also cell cycle regulators (cyclin dependent kinase inhibitor 1A [CDKNA1] and cyclin D1 [CCND1]) and a tissue fibrosis-related molecule (transforming growth factor ß [TGFß]) were identified in ECRSwNP. On the other hand, mainly interferons (IFNs) and acute inflammatory cytokines (IL1 and IL6) were predicted as upstream regulators in NECRSwNP. CONCLUSION: These results are useful for understanding the molecular basis of the mechanisms of CRSwNP and point to new targets for developing specific biomarkers and personalized therapeutic strategies for CRSwNP.

Assessment of suitable reference genes for RT-qPCR studies in chronic rhinosinusitis.

Reverse transcription-quantitative polymerase chain reaction is a valuable and reliable method for gene quantification. Target gene expression is usually quantified by normalization using reference genes (RGs), and accurate normalization is critical for producing reliable data. However, stable RGs in nasal polyps and sinonasal tissues from patients with chronic rhinosinusitis (CRS) have not been well investigated. Here, we used a two-stage study design to identify stable RGs. We assessed the stability of 15 commonly used candidate RGs using five programs-geNorm, NormFinder, BestKeeper, ΔCT, and RefFinder. Ribosomal protein lateral stalk subunit P1 (RPLP1) and ribosomal protein lateral stalk subunit P0 (RPLP0) were the two most stable RGs in the first stage of the study, and these results were validated in the second stage. The commonly used RGs ß-actin (ACTB) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were unstable according to all of the algorithms used. The findings were further validated via relative quantification of IL-5, CCL11, IFN-γ, and IL-17A using the stable and unstable RGs. The relative expression levels varied greatly according to normalization with the selected RGs. Appropriate selection of stable RGs will allow more accurate determination of target gene expression levels in patients with CRS.

Evaluation of YAP signaling in a rat tympanic membrane under a continuous negative pressure load and in human middle ear cholesteatoma.

OBJECTIVES: Mechanotransduction plays an important role in cell-proliferative activities. Negative pressure in the middle ear is thought to be an important factor related to the etiology of acquired middle ear cholesteatoma. However, the correlation between negative pressure in the middle ear and the mechanism of middle ear cholesteatoma formation remains unclear. In this study, we investigated the expression of key molecules for mechanotransduction immunohistochemically. METHODS: An immunohistochemical analysis was performed using anti-Wnt5a (a marker of alternative Wnt signaling), -Yes-associated protein (YAP) (a marker of mechanosensing) and -pYAP (phosphorylated YAP at Ser 127: inactivated YAP) antibody in the tympanic membrane (TM) under a negative pressure load and in human middle ear cholesteatoma tissues. RESULTS: The number of Wnt5a-positive cells had increased and YAP nuclear translocation was observed in epithelial and mesenchymal cells in the pars flaccida (PF) of the TM under a negative-pressure load and in human middle ear cholesteatoma tissues. CONCLUSIONS: We demonstrated that negative pressure in the middle ear might possibly induce cell proliferation PF of TM in response to mechanical force (mechanotransduction) through YAP nuclear translocation mediated by alternative Wnt signaling, thus affecting human middle ear cholesteatoma formation.

Internal Jugular and Subclavian Vein Thrombosis in a Case of Ovarian Cancer.

Central venous catheter insertion and cancer represent some of the important predisposing factors for deep venous thrombosis (DVT). DVT usually develops in the lower extremities, and venous thrombosis of the upper extremities is uncommon. Early diagnosis and treatment of deep venous thrombosis are of importance, because it is a precursor of complications such as pulmonary embolism and postthrombotic syndrome. A 47-year-old woman visited our department with painful swelling on the left side of her neck. Initial examination revealed swelling of the region extending from the left neck to the shoulder without any redness of the overlying skin. Laboratory tests showed a white blood cell count of 5,800/mm3 and an elevated serum C-reactive protein of 4.51 mg/dL. Computed tomography (CT) of the neck revealed a vascular filling defect in the left internal jugular vein to left subclavian vein region, with the venous lumina completely occluded with dense soft tissue. On the basis of the findings, we made the diagnosis of thrombosis of the left internal jugular and left subclavian veins. The patient was begun on treatment with oral rivaroxaban, but the left shoulder pain worsened. She was then admitted to the hospital and treated by balloon thrombectomy and thrombolytic therapy, which led to improvement of the left subclavian venous occlusion. Histopathologic examination of the removed thrombus revealed adenocarcinoma cells, indicating hematogenous dissemination of malignant cells.

The usefulness of measuring tear periostin for the diagnosis and management of ocular allergic diseases.

BACKGROUND: Chronic ocular allergic diseases such as vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are accompanied by serious comorbidities; however, the underlying pathogenesis remains obscure. Furthermore, diagnosing conjunctival lesions in patients with atopic dermatitis and estimating the severity in AKC are important for the treatment of ocular allergic diseases. OBJECTIVE: We addressed whether periostin, a novel mediator and biomarker in allergic inflammation, is involved in the pathogenesis of ocular allergic diseases and whether periostin can be a biomarker for these diseases. METHODS: We investigated tear periostin in patients with seasonal allergic conjunctivitis (SAC), VKC, and AKC and allergic patients without conjunctivitis and compared it with tear IL-13 and serum periostin. Furthermore, in patients with AKC, we measured tear periostin before and after topical treatment with tacrolimus. RESULTS: Tears from patients with ocular allergic disease showed significantly high periostin levels than did tears from allergic patients without conjunctivitis and from patients with AKC, VKC, and SAC in descending order. Tear periostin was associated with serious comorbidities such as large papilla formation and corneal damage in AKC, although both tear IL-13 and serum periostin had little to no such abilities. Furthermore, after topical tacrolimus treatment, tear periostin tended to decrease in most patients with AKC along with their clinical improvement. CONCLUSIONS: Periostin produced in conjunctival tissues stimulated by IL-13 may contribute to the pathogenesis of ocular allergic diseases. Furthermore, tear periostin can be potentially applied as a biomarker to diagnose conjunctivitis in allergic patients and to evaluate disease severity as well as the efficacy of treatments in AKC.

Sinus fungus ball in the Japanese population: clinical and imaging characteristics of 104 cases.

Sinus fungus ball is defined as noninvasive chronic fungal rhinosinusitis occurring in immunocompetent patients with regional characteristics. The clinical and imaging characteristics of paranasal sinus fungus ball were retrospectively investigated in 104 Japanese patients. All patients underwent endoscopic sinus surgery. Preoperative computed tomography (CT), magnetic resonance (MR) imaging, age, sex, chief complaint, causative fungus, and clinical outcome were analyzed. Patients were aged from 25 to 79 years (mean 58.8 years). Female predominance was noted (58.7%). Most common symptoms were nasal discharge and facial pain. CT showed high density area in 82.0% of the cases (82/100), whereas T2-weighted MR imaging showed low intensity area in 100% of the cases (32/32). Histological examination showed that most causative agents were Aspergillus species (94.2% (98/104)). Culture test was positive for 16.7% (11/66). Recurrence was found in 3.2% (3/94). Older age and female predominance were consistent with previous reports. MR imaging is recommended to confirm the diagnosis.

Increased CXCL10 expression in nasal fibroblasts from patients with refractory chronic rhinosinusitis and asthma.

BACKGROUND: Chronic rhinosinusitis (CRS) is characterized by local inflammation of the sinonasal tissues. CRS patients with nasal polyps and asthma often develop acute exacerbation of sinonasal symptoms after upper respiratory tract infections. However, the influence of concomitant asthma on the nasal immune response to viral infection remains unclear. METHODS: Specimens of nasal polyp and mucosal tissues were obtained from 3 groups of CRS patients (n = 14 per group): 1) patients without asthma (CRS group), 2) patients with aspirin-tolerant asthma (ATA group), and 3) patients with aspirin-intolerant asthma (AIA group). Nasal fibroblasts isolated from the specimens were stimulated with poly I:C. CXCL10 expression was analyzed by the quantitative real-time polymerase chain reaction and enzyme-linked immunoadsorbent assay. Biopsy specimens from CRS patients without asthma were subjected to immunohistochemistry for detection of T-bet and GATA-3 expression in CD3+ T cells by double labeling. RESULTS: Nasal fibroblasts from the ATA and AIA groups showed significantly enhanced expression of CXCL10 mRNA and protein after poly I:C stimulation compared with cells from the CRS group and the control group (normal nasal mucosa). In addition to T helper (Th)2 cells, there was more abundant infiltration of Th1 cells into tissues from the AIA and ATA groups. CONCLUSIONS: Our findings suggest that CRS associated with asthma may become intractable through the over-production of CXCL10 in response to viral infection.