Phosphorylation of phase-separated p62 bodies by ULK1 activates a redox-independent stress response.

NRF2 is a transcription factor responsible for antioxidant stress responses that is usually regulated in a redox-dependent manner. p62 bodies formed by liquid-liquid phase separation contain Ser349-phosphorylated p62, which participates in the redox-independent activation of NRF2. However, the regulatory mechanism and physiological significance of p62 phosphorylation remain unclear. Here, we identify ULK1 as a kinase responsible for the phosphorylation of p62. ULK1 colocalizes with p62 bodies, directly interacting with p62. ULK1-dependent phosphorylation of p62 allows KEAP1 to be retained within p62 bodies, thus activating NRF2. p62S351E/+ mice are phosphomimetic knock-in mice in which Ser351, corresponding to human Ser349, is replaced by Glu. These mice, but not their phosphodefective p62S351A/S351A counterparts, exhibit NRF2 hyperactivation and growth retardation. This retardation is caused by malnutrition and dehydration due to obstruction of the esophagus and forestomach secondary to hyperkeratosis, a phenotype also observed in systemic Keap1-knockout mice. Our results expand our understanding of the physiological importance of the redox-independent NRF2 activation pathway and provide new insights into the role of phase separation in this process.

Sarcopenia Index Predicts Short-Term Prognosis of Head and Neck Squamous Cell Carcinoma.

The sarcopenia index (SI), calculated as [(serum creatinine/serum cystatin C) × 100], maybe a simpler alternative for measuring muscle mass than computed tomography (CT) and bioelectrical impedance analysis (BIA). We enrolled 112 patients with head and neck cancers (HNC). The correlation of the SI with muscle surface area measured by CT (CTMSA, n = 82) and muscle mass by BIA (BIA-MM, n = 41) was tested. Cutoff values were set for SI, CTMSA, and BIA-MM. Overall survival (OS) was compared between the high- and low-SI/CTMSA/BIA-MM groups. The SI was correlated with CTMSA (r = 0.43) and BIA-MM (r = 0.52). The optimal cutoff values of SI, CTMSA, and BIA-MM were 76.1 (area under the curve [AUC] = 0.67), 129.2 (AUC = 0.59), and 46.1 (AUC = 0.62), respectively. OS was significantly lower in the low-SI group (78% at 1 year and 69% at 2 years) than in the high-SI group (94% at 1 year and 86% at 2 years; p = 0.006). There was no significant difference in OS between the low-and high-CTMSA and -BIA-MM groups. The SI, which only requires a blood sample, is a useful marker of muscle mass that correlates with short-term prognosis in patients with HNC.

Safety and efficacy of neoadjuvant chemotherapy with paclitaxel, carboplatin, and cetuximab for locally advanced head and neck squamous cell carcinoma.

BACKGROUND: As a substantial waiting time is usually required for radical surgery, safe and effective preoperative neoadjuvant chemotherapy (NAC) is desired for the treatment of locally advanced head and neck squamous cell carcinoma (HNSCC). However, the significance of NAC in advanced HNSCC is still unclear. This study aimed to assess the safety and efficacy of NAC using the paclitaxel, carboplatin, and cetuximab (PCE) regimen. METHODS: We retrospectively evaluated the background characteristics, incidence of adverse events, overall response rate (ORR), pathological response, recurrence-free survival (RFS), and overall survival (OS) in 26 patients. Patients receiving the PCE regimen were further divided into two groups based on the number of chemotherapy cycles (one cycle or more) and eligibility for cisplatin. Patients aged ≥ 75 years and those with an estimated glomerular filtration rate (eGFR) < 60 mL/min were classified as ineligible for cisplatin. RESULTS: The median age was 70 (27-81) years. The median eGFR at treatment initiation was 63.2 (41.1-89.7) mL/min. Fourteen (53.8%) patients were ineligible for cisplatin. Grade 3 or higher neutropenia was observed in 11 of 25 (42.3%) patients. No delay in or withdrawal from surgery was observed. The ORR was 65.4%. The 2-year RFS and OS were 61.5% and 76.7%, respectively. No significant differences in safety and efficacy between the number of chemotherapy cycles and cisplatin eligibility were observed. CONCLUSION: NAC using the PCE regimen for patients with locally advanced HNSCC, including cisplatin-ineligible patients, has acceptable toxicity and favorable efficacy.

Multicenter prospective phase II trial of concurrent chemoradiotherapy with weekly low-dose carboplatin for cisplatin-ineligible patients with advanced head and neck squamous cell carcinoma.

BACKGROUND: The optimal chemotherapy regimen in concurrent chemoradiotherapy (CCRT) for cisplatin-ineligible head and neck squamous cell carcinoma (HNSCC) has not been established. We aimed to evaluate the feasibility, efficacy, and safety of CCRT with weekly low-dose carboplatin for the treatment of advanced HNSCC in patients who are cisplatin-ineligible. METHODS: This prospective phase II study enrolled adult patients (age ≥ 20 years) with HNSCC receiving whole-neck irradiation including bilateral levels II-IV and who were aged (≥ 75-year-old patients with 40 mL/min estimated glomerular filtration rate [eGFR] or better) or had renal dysfunction (< 75-year-old patients with 30-60 mL/min eGFR). Carboplatin was administered weekly (area under the plasma concentration-time curve = 2.0) for up to seven cycles during concurrent radiotherapy (70 Gy/35 Fr). The primary endpoint was the completion rate of CCRT. Secondary endpoints included overall response rate and incidence of adverse events. RESULTS: Among the 30 patients enrolled, 28 were men. The median age was 73.5 years. Seventeen patients were < 75 years whereas 13 were ≥ 75 years old. The completion rate of CCRT was 90%. The overall response rate was 90%. Grade 3 adverse events that occurred in 10% or more patients were oral/pharyngeal mucositis (47%), leukocytopenia (20%), and neutropenia (10%). Grade 4 adverse events occurred in one patient (elevation of alanine aminotransferase level). No treatment-related deaths occurred. CONCLUSION: CCRT with weekly low-dose carboplatin is a promising treatment option, with favorable feasibility, efficacy, and acceptable toxicity, for patients who are cisplatin-ineligible with advanced HNSCC. CLINICAL TRIAL REGISTRATION NUMBER: jRCTs031190028.

Aortic rupture following acute aortitis in a patient with head and neck carcinoma treated with nivolumab: a rare but severe immune-related adverse event.

INTRODUCTION: Immune-related adverse events (irAEs) due to immune checkpoint inhibitors may lead to discontinuation and treatment-related death. Acute aortitis is a rare but severe irAE. CASE PRESENTATION: A 67-year-old man with recurrent lower gingival carcinoma received nivolumab therapy. Twenty-three months later, he experienced chest compression, which resulted in syncope. Following a whole-body computed tomography (CT) scanning, which revealed diffuse thickening of the aorta, and systemic assessments of the causes of aortitis, he was diagnosed with acute aortitis due to irAE. Nivolumab discontinuation and oral steroids improved CT findings. However, 11 months after nivolumab discontinuation, he developed an aortic aneurysmal rupture. Endovascular aortic repair rescued him. A durable anti-cancer response was still observed 4 months after the aortic rupture. CONCLUSION: Although severe irAE, such as acute aortitis, occurred, the patient may still achieve a durable response. A broad examination and prompt treatment of irAE can help improve the patient's survival.

Plus moist HS-W®: a new nasal packing material for the middle meatus in endoscopic sinus surgery.

PURPOSE: Removal of the current calcium alginate packing materials to the middle meatus in endoscopic sinus surgery (ESS) is usually accompanied by discomfort or pain owing to the hard and brittle nature of these materials. Plus moist HS-W® is a new calcium alginate packing material released in 2022 developed to overcome this issue by changing the uronic acid component. We aimed to compare the discomfort/pain during the removal of Plus moist HS-W® with Kaltostat®, as well as their suitability as packing materials in ESS. METHODS: Kaltostat® and Plus moist HS-W® were used as packing materials in 22 and 21 patients who underwent ESS in 2021 and 2022, respectively. Patients were asked to rate the pain during the packing removal 10 days after ESS using the Numerical Rating Scale (NRS). The ratio of residual packing materials, number of suctions (insertions/extractions of the suction cannula), and time required to remove packing materials were measured. Postoperative complications such as hemorrhage, local infection, lateralization of the middle turbinate, and synechia of the middle meatus were also evaluated. RESULTS: The Plus moist HS-W® group exhibited significantly lower NRS pain scores, a lower ratio of residual packing materials, a reduced number of suctions, and a shorter time required to remove the packing. No obvious postoperative complications occurred in both groups except for one suspicious case of a slight infection in the Kaltostat® group. CONCLUSION: Compared with Kaltostat®, Plus moist HS-W®, characterized by better gelatinization than Kaltostat®, benefits patients by minimizing discomfort/pain during removal. LEVEL OF EVIDENCE: Level 3.

Effect of Dupilumab on Depression in Asthma with Eosinophilic Chronic Rhinosinusitis in the Japanese Population.

INTRODUCTION: Psychological disorders, such as depression, are markedly prevalent in patients with airway diseases. In this study, we assessed the effect of treatment with dupilumab, an IL-4 receptor α chain antibody, on depressive symptoms in a cohort of patients with asthma with eosinophilic chronic rhinosinusitis (ECRS). METHODS: The study participants, diagnosed with asthma and ECRS, were assessed for symptoms and quality of life (QOL) scores for asthma and ECRS and medications. The Patient Health Questionnaire-9 (PHQ-9) scores were used to evaluate the depressive state. The depressive symptoms were compared with asthma and ECRS symptoms both at the time of initiation and after 4 months of dupilumab treatment. RESULTS: Ultimately, 31 patients were included in the study. Most patients demonstrated a depressive state that was correlated with the nasal symptom score. In the evaluation 4 months after dupilumab treatment, the PHQ-9 score was significantly reduced, and the decrease was remarkable in patients whose nasal symptom score was reduced by 50% or more. Additionally, the PHQ-9 scores in patients with improved nasal and asthma symptoms were significantly reduced. DISCUSSION/CONCLUSION: Dupilumab may improve QOL in patients with bronchial asthma with ECRS by reducing depressive symptoms through the improvement of clinical symptoms.

Electrochemical properties of the non-excitable tissue stria vascularis of the mammalian cochlea are sensitive to sounds.

Excitable cochlear hair cells convert the mechanical energy of sounds into the electrical signals necessary for neurotransmission. The key process is cellular depolarization via K+ entry from K+ -enriched endolymph through hair cells' mechanosensitive channels. Positive 80 mV potential in endolymph accelerates the K+ entry, thereby sensitizing hearing. This potential represents positive extracellular potential within the epithelial-like stria vascularis; the latter potential stems from K+ equilibrium potential (EK ) across the strial membrane. Extra- and intracellular [K+ ] determining EK are likely maintained by continuous unidirectional circulation of K+ through a putative K+ transport pathway containing hair cells and stria. Whether and how the non-excitable tissue stria vascularis responds to acoustic stimuli remains unclear. Therefore, we analysed a cochlear portion for the best frequency, 1 kHz, by theoretical and experimental approaches. We have previously developed a computational model that integrates ion channels and transporters in the stria and hair cells into a circuit and described a circulation current composed of K+ . Here, in this model, mimicking of hair cells' K+ flow induced by a 1 kHz sound modulated the circulation current and affected the strial ion transport mechanisms; the latter effect resulted in monotonically decreasing potential and increasing [K+ ] in the extracellular strial compartment. Similar results were obtained when the stria in acoustically stimulated animals was examined using microelectrodes detecting the potential and [K+ ]. Measured potential dynamics mirrored the EK change. Collectively, because stria vascularis is electrically coupled to hair cells by the circulation current in vivo too, the strial electrochemical properties respond to sounds. KEY POINTS: A highly positive potential of +80 mV in K+ -enriched endolymph in the mammalian cochlea accelerates sound-induced K+ entry into excitable sensory hair cells, a process that triggers hearing. This unique endolymphatic potential represents an EK -based battery for a non-excitable epithelial-like tissue, the stria vascularis. To examine whether and how the stria vascularis responds to sounds, we used our computational model, in which strial channels and transporters are serially connected to those hair cells in a closed-loop circuit, and found that mimicking hair cell excitation by acoustic stimuli resulted in increased extracellular [K+ ] and decreased the battery's potential within the stria. This observation was overall verified by electrophysiological experiments using live guinea pigs. The sensitivity of electrochemical properties of the stria to sounds indicates that this tissue is electrically coupled to hair cells by a radial ionic flow called a circulation current.

Aberrant mucosal immunoreaction to tonsillar microbiota in immunoglobulin A nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is the most common glomerulonephritis worldwide, characterized by mesangial polymeric IgA1 deposition. IgAN is believed to develop owing to aberrant mucosal immunoreaction against commensals in the tonsils. However, the exact interrelation between pathogenic IgA and mucosal microbiota in IgAN patients is unclear. METHODS: Biopsy-proven IgAN or recurrent tonsillitis (RT) patients who had undergone tonsillectomy were enrolled. We used 16S ribosomal RNA gene amplicon sequencing with a flow cytometry-based bacterial cell sorting technique) and immunoglobulin repertoire sequencing of the IgA heavy chain to characterize IgA-coated bacteria of the tonsillar microbiota (IgA-SEQ) and their corresponding IgA repertoire. Furthermore, we fractionated patient serum using gel-filtration chromatography and performed flow cytometry-based analysis of IgA binding to bacteria cultured from incised tonsils. RESULTS: Tonsillar proliferation-inducing ligand and B-cell activating factor levels were significantly higher in IgAN than in RT patients. IgA-SEQ for tonsillar microbiota revealed the preferential binding ability of IgA to Bacteroidetes in IgAN tonsils compared with those from RT patients. Expression of immunoglobulin heavy (IGH) constant alpha 1 with IGH variable 3-30 was significantly higher in IgAN than that in RT, and positively correlated with the IgA-coated enrichment score of Bacteroidetes. Serum polymeric IgA, comprising high levels of GdIgA1, exhibited considerable binding to Bacteroidetes strains cultured from the tonsils of IgAN patients. CONCLUSIONS: These findings provide evidence that aberrant mucosal immune responses to tonsillar anaerobic microbiota, primarily consisting of members of the phylum Bacteroidetes, are involved in IgAN pathophysiology.

Sarcopenia predicts a poor treatment outcome in patients with head and neck squamous cell carcinoma receiving concurrent chemoradiotherapy.

PURPOSE: Sarcopenia, defined as a decrease in the skeletal muscle mass and its function, is associated with a poor clinical outcome in several malignancies. We aimed to examine whether sarcopenia can be a predictor of incompletion of concurrent chemoradiotherapy (CCRT) and survival for head and neck cancer (HNC) patients. METHODS: Forty-one male HNC patients who received CCRT were enrolled in the study. Cross-sectional muscle areas at the third lumbar vertebral level were normalized by the squared height of the patients and were termed the lumbar skeletal muscle index (LSMI, cm2/m2), a marker of sarcopenia. Patients were divided into high (30/41, 73%) and low (11/41, 27%) LSMI groups. The LSMI cut-off value was set at 39.7 cm2/m2 based on a receiver operating characteristic curve for incompletion of CCRT. The groups were compared for survival rate by the Kaplan-Meier method. Factors predicting incompletion of CCRT were investigated among several variables. RESULTS: Multivariate analysis showed that a pre-treatment low LSMI (P = 0.033) and age over 70 years (P = 0.023) were the only significant predictors for incompletion of CCRT. The 2-year disease-specific survival (DSS) rate was significantly lower in the low LSMI group (61%) than in the high LSMI group (97%, P = 0.012), whereas there were no differences in the DSS rate between the low and high body mass index groups. CONCLUSION: The prevalence of sarcopenia in HNC patients receiving CCRT was 27%. Its presence before treatment was a significant predictor of incomplete CCRT and poor DSS rate in HNC patients.

Prediction of effectiveness of potassium-competitive acid blocker and serotonin noradrenaline reuptake inhibitor on abnormal sensation in the throat: use of patient-reported outcome measures (PROMs).

PURPOSE: To determine patients with abnormal sensation in the throat (AST) who would respond to potassium-competitive acid blocker (P-CAB) or serotonin noradrenaline reuptake inhibitor (SNRI) treatment. METHODS: AST patients were randomly divided into two groups. Thirty-one and 21 patients received P-CAB and SNRI treatment, respectively. GETS-J, the Japanese version of Glasgow Edinburgh Throat Scales (GETS), consisted of three subscales of throat symptoms (globus sensation, pain/swelling of the throat, and dysphagia) and somatic distress due to the disease, Frequency Scale for the Symptoms of Gastro-esophageal reflux disease (FSSG), and Hospital Anxiety and Depression Scale (HADS) were used before and after treatments. Responders to treatments were defined as those who showed 50% or more decrease in symptom scores or somatic distress. RESULTS: Pre-treatment GETS-J pain/swelling scores and FSSG acid reflux scores were higher in P-CAB responders and decreased after treatment. Receiver operating characteristic curve for pain/swelling subscale had an area under the curve (AUC) of 0.792 to predict P-CAB responders and a score of 11 provided the best combination of sensitivity (62.5%) and specificity (80%). Somatic distress and HADS anxiety scores, but no other GETS-J symptom scores, decreased after SNRI treatment. Pre-treatment globus scores were lower in SNRI responders. AUC value for globus subscale to predict SNRI responders was 0.741 and a score of 6.5 provided the best combination of sensitivity (70%) and specificity (73%). CONCLUSIONS: Pain/swelling is a characteristic symptom in AST patients who respond to P-CAB treatment. SNRI treatment would be effective for somatic distress in cases with mild symptoms.

Predicting the treatment outcome of nivolumab in recurrent or metastatic head and neck squamous cell carcinoma: prognostic value of combined performance status and modified Glasgow prognostic score.

PURPOSE: The importance of nivolumab for recurrent or metastatic (R/M) head and neck squamous cell carcinoma (HNSCC) is rapidly increasing. However, prognostic factors have not been determined for predicting treatment outcome. We aimed to investigate the prognostic factors in R/M HNSCC patients treated with nivolumab. METHODS: This retrospective study included 42 patients with R/M HNSCC who received nivolumab therapy. Correlations of overall survival (OS) with various patient characteristics including age, recurrent/metastatic site, performance status (PS), programmed death-ligand 1 positivity, body mass index, neutrophil-to-lymphocyte ratio, modified Glasgow prognostic score (mGPS), previous cetuximab administration, and immune-related adverse events were investigated. RESULTS: The overall response rate and disease control rate were 16.7% and 45.2%, respectively. Estimated 1-year OS and progression-free survival (PFS) were 56.4% and 24.5%, respectively. Multivariate analysis revealed that PS = 2 (hazard ratio 0.147; 95% CI 0.041-0.527; p = 0.003) and mGPS = 2 (hazard ratio 0.188; 95% CI, 0.057-0.620; p = 0.006) were independent predictors of poor OS. Given that the PS and mGPS were independent prognostic factors, we classified patients into three groups according to PS and mGPS: Group 1, both PS and mGPS were 0 or 1 (n = 30); Group 2, either PS or mGPS was 2 (n = 9); Group 3, both PS and mGPS were 2 (n = 3). The OS curves were significantly stratified among the three groups. CONCLUSION: The combination of PS and mGPS accurately predicted OS after nivolumab therapy. Preventive intervention to maintain general condition without simultaneously exceeding level 2 of PS and mGPS might be important for improving treatment outcomes of nivolumab.

Rat Model of Ménière's Attack: Intratympanic Injection of Potassium Chloride Produces Direction-Changing Spontaneous Nystagmus and Hearing Fluctuations.

The major symptoms of Ménière's disease are episodic vertigo, fluctuating hearing loss, and tinnitus. Direction-changing spontaneous nystagmus is a characteristic vestibular finding in Ménière's disease. In the acute stage, spontaneous nystagmus beating to the affected side (irritative nystagmus) is often observed, while paralytic nystagmus beating to the healthy side is found in the chronic stage. This direction-changing nystagmus can be reproduced in guinea pigs by increasing the potassium ion concentration in the perilymph. The objectives of the present study were to examine the effects of increasing the potassium ion concentration of the rat perilymph on hearing and nystagmus. Under isoflurane anesthesia, 22 rats received intratympanic injection of different concentrations of potassium chloride (KCl) solution or distilled water: groups 1, 2, 3, and 4 received saturated (3.4 M) KCl solution, 2 M KCl, 1 M KCl, and distilled water, respectively. The nystagmus direction and number per 15 s were monitored for 150 min. In the other 8 rats, hearing was monitored 30 min and 20 h after intratympanic injection of 2 M KCl (group 5) or distilled water (group 6) using the auditory brainstem responses. Rats in groups 1 and 2 showed spontaneous irritative nystagmus beating to the affected ear followed by paralytic nystagmus beating to the contralateral side. In group 3, irritative nystagmus occurred but paralytic nystagmus was rarely observed. Rats in group 4 showed no nystagmus. Rats in group 5 showed significant hearing impairment 30 min after KCl injection that recovered 20 h later. Control animals in group 6 showed no significant changes in hearing. The reversible hearing impairment with direction-changing spontaneous nystagmus induced by potassium injection into the tympanic cavity in rats was quite similar to that observed in acute Ménière's attacks. This rat model could be used for basic research investigating the pathophysiological mechanisms underlying Ménière's attacks.

Otosclerosis: anatomical distribution of otosclerotic loci analyzed by high-resolution computed tomography.

PURPOSE: To clarify the anatomical distribution of otosclerotic loci in otosclerosis. METHODS: Ninety-five patients with surgically confirmed uni- or bilateral otosclerosis were enrolled into the study. Hypodense areas observed in the otic capsule by high-resolution computed tomography (HRCT) were defined as otosclerotic loci. The location and number of lesions were examined, and the probability of lesion overlap and correlation with age/hearing parameters (air and bone conduction threshold, air-bone gaps) were tested. RESULTS: Otosclerotic loci were confirmed by HRCT in 77 out of 115 operated ears. The three commonly affected sites were the anterior part of the oval window (ant-OW), anterior part of the internal auditory canal (ant-IAC), and pericochlear area (PCochA), with lesions detected in 96.1%, 46.8%, and 26.0% of ears, respectively. Only the ant-OW area was affected in 48.1% of the ears; the ant-IAC in 3.9%; and PCochA in none with significant differences (p < 0.01). The ant-OW lesions preferentially overlapped with ant-IAC (44.6%) than PCochA lesions (27.0%) (p < 0.05). Among double sites diseases, triple sites diseases occurred more commonly in the ant-OW + PCochA group (80%) than ant-OW + ant-IAC group (48.5%) (p < 0.05). There was no correlation between a number of lesions and age/hearing parameters. CONCLUSIONS: Based on the probability of lesion overlap, otosclerotic lesions may initiate at ant-OW followed by ant-IAC and later PCochA. Although the number of lesions showed no immediate correlation with hearing level or age, anatomical stage of the disease estimated by the location and the number of otosclerotic loci could be useful in predicting the future hearing status.

Lower Airway Inflammation in Eosinophilic Chronic Rhinosinusitis as Determined by Exhaled Nitric Oxide.

BACKGROUND: Chronic rhinosinusitis (CRS) is classified into eosinophilic CRS (ECRS) and non-ECRS. The objectives of this study were to evaluate lower airway inflammation by measuring the fractional concentration of exhaled nitric oxide (FeNO) and to examine the effects of endoscopic sinus surgery (ESS) on FeNO in patients with ECRS compared to non-ECRS. METHODS: CRS patients with nasal polyps (23 with ECRS and 22 with non-ECRS) were enrolled into this study. ECRS was diagnosed based on the definition proposed by the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis (JESREC) study group. Several clinical markers including blood eosinophil counts, percent of eosinophils in white blood cells (WBC), number of eosinophils in nasal polyps, JESREC scores, total IgE, FeNO, and Lund-Mackay paranasal sinus CT scores were compared between ECRS and non-ECRS. These markers were also tested before and 2 months after ESS. RESULTS: FeNO was significantly higher in patients with ECRS than in non-ECRS patients. When all CRS patients were tested, a significant correlation was found between FeNO and eosinophilic markers including blood eosinophil counts, percent of eosinophils in WBC, number of eosinophils in nasal polyps, and JESREC scores. FeNO showed a significant correlation with Lund-Mackay scores only in ECRS patients. Blood eosinophil counts, percent of eosinophils in WBC, and FeNO decreased after ESS only in ECRS patients. CONCLUSIONS: ECRS patients had lower airway inflammation as revealed by an elevated FeNO, which was parallel to the Lund-Mackay CT scores. ESS decreased the blood eosinophils and FeNO, leading to an improvement of the occult pulmonary dysfunction in ECRS patients.

Comprehensive microbiome analysis of tonsillar crypts in IgA nephropathy.

BACKGROUND: Immunoglobulin A nephropathy (IgAN) is the most prevalent primary chronic glomerular disease, in which the mucosal immune response elicited particularly in the tonsils or intestine has been estimated to be involved in the development of the disease. To explore the relationship between IgAN and bacterial flora in the tonsils, we conducted a comprehensive microbiome analysis. METHODS: We enrolled 48 IgAN patients, 21 recurrent tonsillitis (RT) patients without urine abnormalities and 30 children with tonsillar hyperplasia (TH) who had undergone tonsillectomy previously. Genomic DNA from tonsillar crypts of each patient was extracted, and V4 regions of the 16S ribosomal RNA gene were amplified and analysed using a high-throughput multiplexed sequencing approach. Differences in genus composition among the three study groups were statistically analysed by permutational multivariate analysis of variance and visualized by principal component analysis (PCA). RESULTS: Substantial diversity in bacterial composition was detected in each sample. Prevotella spp., Fusobacterium spp., Sphingomonas spp. and Treponema spp. were predominant in IgAN patients. The percentage of abundance of Prevotella spp., Haemophilus spp., Porphyromonas spp. and Treponema spp. in IgAN patients was significantly different from that in TH patients. However, there was no significant difference in the percentage of abundance of any bacterial genus between IgAN and RT patients. PCA did not distinguish IgAN from RT, although it discriminated TH. No significant differences in microbiome composition among the groups of IgAN patients according to clinicopathological parameters were observed. CONCLUSIONS: Similar patterns of bacteria are present in tonsillar crypts of both IgAN and RT patients, suggesting that the host response to these bacteria might be important in the development of IgAN.

Evaluation of endolymphatic hydrops using 3-T MRI after intravenous gadolinium injection.

Aim of this work is to establish evaluation criteria for identifying endolymphatic hydrops in the vestibule and cochlea using a magnetic resonance imaging (MRI) scanner. This is a retrospective diagnostic study. We evaluated 70 ears of 35 unilateral Ménière's disease patients. We performed 3-T MRI 4 h after intravenous gadolinium injection. Otologists manually traced the outline of vestibule, cochlea, and endolymphatic space of the vestibule and cochlea on two-dimensional fluid-attenuated inversion-recovery (2D-FLAIR) images. The traced area was measured, and rates of endolymphatic space to the vestibule and cochlea were calculated. The same otologists judged whether the low signal intensity area of the cochlea was at the edge of the cochlea. For measuring the rate of endolymphatic space to the vestibule, when the cut-off value was 30%, the presence of endolymphatic hydrops was determined with sensitivity of 87.1% and specificity of 94.3%. In contrast, the rate of endolymphatic space to the cochlea produced low accuracy. Therefore, when the presence of endolymphatic hydrops in the cochlea was judged by whether the low signal intensity area in the cochlea was at the edge of cochlea, endolymphatic hydrops could be detected with sensitivity of 91.4% and specificity of 94.3%. We were able to identify endolymphatic hydrops in the vestibule when the rate of endolymphatic space to the vestibule was greater than 30%, and could detect endolymphatic hydrops in the cochlea when a low signal intensity area was located at the edge of the cochlea in 2D-FLAIR images. Level of evidence 4.

Functional Expression of an Osmosensitive Cation Channel, Transient Receptor Potential Vanilloid 4, in Rat Vestibular Ganglia.

Transient receptor potential vanilloid (TRPV) 4 is a nonselective cation channel expressed in sensory neurons such as those in the dorsal root and trigeminal ganglia, kidney, and inner ear. TRPV4 is activated by mechanical stress, heat, low osmotic pressure, low pH, and phorbol derivatives such as 4α-phorbol 12,13-didecanoate (4α-PDD). We investigated the expression of TRPV4 in rat vestibular ganglion (VG) neurons. The TRPV4 gene was successfully amplified from VG neuron mRNA using reverse-transcription polymerase chain reaction. Furthermore, immunoblotting showed positive expression of TRPV4 protein in VG neurons. Immunohistochemistry indicated that TRPV4 was localized predominantly on the plasma membrane of VG neurons. Calcium (Ca2+) imaging of VG neurons showed that 4α-PDD and/or hypotonic stimuli caused an increase in intracellular Ca2+ concentration ([Ca2+]i) that was almost completely inhibited by ruthenium red, a selective antagonist of TRPV channels. Interestingly, a [Ca2+]i increase was evoked by both hypotonic stimuli and 4α-PDD in approximately 38% of VG neurons. These data indicate that TRPV4 is functionally expressed in VG neurons as an ion channel and that TRPV4 likely participates in VG neurons for vestibular neurotransmission as an osmoreceptor and/or mechanoreceptor.

[A Case of Cystic Cervical Lymph Node Metastasis of HPV-positive Tonsil Cancer, Being Discriminated as the Branchiogenic Carcinoma].

In recent years, human papillomavirus (HPV)-positive oropharyngeal carcinomas have been increasing. The first manifestation of these tumors is frequently as cystic metastasis to cervical lymph nodes that may precede recognition of the primary tumor, so, they often result in misdiagnosis as branchial cleft cysts. We report a case of cystic cervical lymph node metastasis of HPV-positive tonsil cancer. The patient was a 70-years-old man who noticed a mass on his left neck. The tumor was large and soft, and it was diagnosed as benign in fine-needle aspiration cytology. We diagnosed the tumor as a branchial cleft cyst and undertook surgery. The histopathological diagnosis was squamous cell carcinoma arising from a branchiogenic cyst. However, because it did not satisfy the diagnostic criteria, we diagnosed the tumor as an unknown primary tumor. One year later, left tonsil cancer was suspected based on PET-CT imaging and a left tonsillectomy was undertaken, whereafter tonsil cancer was found. In p16 immunostaining, it was positive in both cystic mass and tonsil. The cervical mass was cystic lymph node metastasis of HPV-positive tonsil cancer. It is important to investigate the oropharynx, when we found cystic cervical mass, because HPV-positive oropharyngeal carcinoma frequently results in cystic neck metastasis.