Loss of synaptic ribbons is an early cause in ROS-induced acquired sensorineural hearing loss.

Considerable evidence of reactive oxygen species (ROS) involvement in cochlear hair cell (HC) loss, leading to acquired sensorineural hearing loss (SNHL), were reported. Cochlear synaptopathy between HCs and spiral ganglion neurons has been gathering attention as a cochlear HC loss precursor not detectable by normal auditory evaluation. However, the molecular mechanisms linking ROS with HC loss, as well as the relationship between ROS and cochlear synaptopathy have not been elucidated. Here, we examined these linkages using NOX4-TG mice, which constitutively produce ROS without stimulation. mRNA levels of Piccolo 1, a major component of the synaptic ribbon (a specialized structure surrounded by synaptic vesicles in HCs), were decreased in postnatal day 6 NOX4-TG mice cochleae compared to those in WT mice; they were also decreased by noise exposure in 2-week-old WT cochleae. As noise exposure induces ROS production, this suggests that the synaptic ribbon is a target of ROS. The level of CtBP2, another synaptic ribbon component, was significantly lower in NOX4-TG cochleae of 1-month-old and 4-month-old mice compared to that in WT mice, although no significant differences were noted at 1.5- and 2-months. The decrease in CtBP2 plateaued in 4-month-old NOX4-TG, while it gradually decreased from 1 to 6 months in WT mice. Furthermore, CtBP2 level in 2-month-old NOX4-TG mice decreased significantly after exposure to cisplatin and noise compared to that in WT mice. These findings suggest that ROS lead to developmental delays and early degeneration of synaptic ribbons, which could be potential targets for novel therapeutics for ROS-induced SNHL.

Vestibular schwannoma extending into the tympanic cavity and jugular fossa by invasion of the petrous bone.

Vestibular schwannomas usually originate in the internal acoustic meatus, and gradually extends into the cerebellopontine cistern. Invasive growth into the petrous bone is extremely rare. We describe a case of a vestibular schwannoma that aggressively extended into the petrous bone and extracranial space. This may have arisen because of an unusually peripheral site of origin on the vestibular nerve.

Glycoprotein NMB promotes tumor formation and malignant progression of laryngeal squamous cell carcinoma.

Laryngeal squamous cell carcinoma (LSCC), although one of the most common head and neck cancers, has a static or slightly decreased survival rate because of difficulties in early diagnosis, lack of effective molecular targeting therapy, and severe dysfunction after radical surgical treatments. Therefore, a novel therapeutic target is crucial to increase treatment efficacy and survival rates in these patients. Glycoprotein NMB (GPNMB), whose role in LSCC remains elusive, is a type 1 transmembrane protein involved in malignant progression of various cancers, and its high expression is thought to be a poor prognostic factor. In this study, we showed that GPNMB expression levels in LSCC samples are significantly higher than those in normal tissues, and GPNMB expression is observed mostly in growth-arrested cancer cells. Furthermore, knockdown of GPNMB reduces monolayer cellular proliferation, cellular migration, and tumorigenic growth, while GPNMB protein displays an inverse relationship with Ki-67 levels. Therefore, we conclude that GPNMB may be an attractive target for future LSCC therapy.

Are Intraoral Stents Effective for Reducing the Severity of Oral Mucositis During Radiotherapy for Maxillary and Nasal Cavity Cancer?

PURPOSE: The intraoral stent (IOS) is an individualized mouth opening device that can be used during radiotherapy (RT) for head and neck cancer to prevent unnecessary irradiation to normal tissues. The purpose of the present study was to compare the severity of oral mucositis (OM) between patients using and not using an IOS during RT for maxillary and nasal cavity cancer. PATIENTS AND METHODS: We designed and implemented a retrospective cohort study. The study sample included patients with maxillary and nasal cavity cancer who had undergone RT. The primary predictor variable was IOS application, and the outcome variable was the grade of OM. RESULTS: The IOS group included 18 patients with an IOS and the control group, 16 patients without an IOS. The parameters of the dose-volume histogram included the median dosage covering 1 mL (D1mL) for the tongue and the mean dosage. The D1mL (36.2 vs 65.4 Gy) and mean dosage (4.9 Gy vs 25.9 Gy) were both significantly lower in the IOS group than in the control group (P < .005). The incidence of OM using the National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0, were significantly different between the oral stomatitis grade and the use of an IOS (P = .028). A significant difference was found in opioid use between the IOS and control groups (P = .009). CONCLUSIONS: The use of an IOS decreased the radiation dosage to the tongue, the grade of OM, and opioid usage during RT.

Development of a relational workplace social capital scale for Japanese nurses.

BACKGROUND: Although nurses' workplace social capital for a healthy work environment has received considerable attention, few scales about nurses' workplace social capital are based on the attributes of clinical settings in Japan. This study aims to develop a Relational Workplace Social Capital Scale for Japanese Nurses (RWSCS-JN), which includes bonding, linking, and bridging social capital and assessing its reliability and validity. METHODS: We assessed its reliability and validity using questionnaire survey data collected from 309 nurses in the first survey and 105 nurses in the second survey in four hospitals in Japan. First, we determined the number of factors and items for the RWSCS-JN through the parallel and factor analyses after conducting the item analysis. Then, we confirmed the omega coefficients and intraclass correlation coefficients (ICC) of the RWSCS-JN. Finally, we examined the Pearson product-moment correlation coefficient between the RWSCS-JN score and other variables, including an existing measurement of workplace social capital, work engagement, and turnover intention. RESULTS: The newly developed RWSCS-JN contained 15 items, comprising three factors as follows: bonding social capital, linking social capital, and bridging social capital. The omega coefficient and the ICC of the RWSCS-JN were 0.90 and 0.85, respectively. The Pearson product-moment correlation coefficient between the RWSCS-JN and the existing scale of the workplace social capital was 0.88 (p < 0.01). Furthermore, the Pearson product-moment correlation coefficient between the RWSCS-JN and work engagement was 0.36 (p < 0.01) and that of the RWSCS-JN and turnover intention was - 0.40 (p < 0.01). CONCLUSIONS: This study suggests that the RWSCS-JN could be sufficiently useful for a healthy work environment in a clinical setting.

A comparative study of the physiological and psychological effects of forest bathing (Shinrin-yoku) on working age people with and without depressive tendencies.

BACKGROUND: In recent years, many of Japanese workers have complained of fatigue and stress, considering them as risk factors for depression. Studies have found that "forest bathing" (Shinrin-yoku) has positive physiological effects, such as blood pressure reduction, improvement of autonomic and immune functions, as well as psychological effects of alleviating depression and improving mental health. In this study, we investigate the physiological and psychological effects of "forest bathing" on people of a working age with and without depressive tendencies. METHODS: We conducted physiological measurements and psychological surveys before and after forest bathing with subjects who participated in day-long sessions of forest bathing, at a forest therapy base located in Hiroshima Prefecture. After excluding severely depressed individuals, the participants were classified into two groups: those with depressive tendencies (5 ≤ K6 ≤ 12) and those without depressive tendencies (K6 < 5) for comparative study. The evaluation indices measured were systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse rate (PR), autonomic functions, and profile of mood states (POMS). RESULTS: Of the 155 participants, 37% had depressive tendencies, without any differences observed between males and females. All participants showed significant decrease in SBP, DBP, and in negative POMS items after a forest bathing session. Before the session, those with depressive tendencies scored significantly higher on the POMS negative items than those without depressive tendencies. After forest bathing, those with depressive tendencies demonstrated significantly greater improvement in many of POMS items than those without depressive tendencies, and many of them no longer differed between those with and without depressive tendencies. CONCLUSIONS: Examining the physiological and psychological effects of a day-long session of forest bathing on a working age group demonstrated significant positive effects on mental health, especially in those with depressive tendencies. Not applicable; this is not a report of intervention trial.

A qualitative study on the attributes of nurses' workplace social capital in Japan.

AIM: To identify attributes of nurses' workplace social capital in Japan. BACKGROUND: Much attention has been paid to nurses' workplace social capital to improve the quality of the work environment; however, few studies are available on the attributes of nurses' workplace social capital. METHODS: Semi-structured interviews were conducted with 32 nurses at seven hospitals. Nurses reported on the attributes of workplace social capital, such as characteristics facilitating individual positive action in an organisation, which were qualitatively analysed using the Kawakita Jiro method. RESULTS: The attributes of nurses' workplace social capital were organised into six groups: affirmation; exchange of appreciation; unrestricted information sharing; ability to trust; access to the strength; and altruistic reciprocity. CONCLUSION: The attributes of nurses' workplace social capital included a social structure that allowed nurses to make full use of their abilities both vertically and horizontally and were supported by a sense of security. In particular, newly emerged exchange of appreciation and altruistic reciprocity were important for nurses in Japan in building cooperative relationships with others. IMPLICATIONS FOR NURSING MANAGEMENT: Managing human relationships, such as exchange of appreciation and altruistic reciprocity, in clinical settings based on nurses' workplace social capital may promote positive emotions in the organisation, positive ideas among staff and cooperative teamwork, which may lead to high-quality patient care.

Ceramide/sphingomyelin cycle involvement in gentamicin-induced cochlear hair cell death.

Ceramide, a sphingolipid metabolite, regulates diverse cellular processes including apoptosis, cell senescence, the cell cycle, and cellular differentiation. Exogenously administered ceramide reportedly increased cochlear hair cell death due to gentamicin-induced ototoxicity. Ceramide is mainly generated via a ceramide/sphingomyelin cycle by sphingomyelinase and sphingomyelin synthase or via de novo synthesis by serine palmitoyltransferase and ceramide synthase. This study was designed to investigate the possible involvement of neutral sphingomyelinase, sphingomyelin synthase, or serine palmitoyltransferase in hair cell death due to gentamicin. The basal turns of the organ of Corti of Sprague-Dawley rats were dissected on postnatal days 3-5. Cochlear cultures were exposed to media containing 35 µM gentamicin for 48 h to assess the effects of GW4869 (a neutral sphingomyelinase inhibitor), 2-hydroxyoleic acid (a sphingomyelin synthase activator), and myriocin (a serine palmitoyltransferase inhibitor). Hair cell loss was significantly decreased in the presence of GW4869 or 2-hydroxyoleic acid. Myriocin had no significant effects against gentamicin-induced hair cell loss. In addition, neutral sphingomyelinase was activated by gentamicin exposure. The present findings strongly suggest that the ceramide/sphingomyelin cycle plays an important role in the protection of hair cells against gentamicin-induced ototoxicity.

A randomized controlled clinical trial of topical insulin-like growth factor-1 therapy for sudden deafness refractory to systemic corticosteroid treatment.

BACKGROUND: To date, no therapeutic option has been established for sudden deafness refractory to systemic corticosteroids. This study aimed to examine the efficacy and safety of topical insulin-like growth factor-1 (IGF-1) therapy in comparison to intratympanic corticosteroid therapy. METHODS: We randomly assigned patients with sudden deafness refractory to systemic corticosteroids to receive either gelatin hydrogels impregnated with IGF-1 in the middle ear (62 patients) or four intratympanic injections with dexamethasone (Dex; 58 patients). The primary outcome was the proportion of patients showing hearing improvement (10 decibels or greater in pure-tone average hearing thresholds) 8 weeks after treatment. The secondary outcomes included the change in pure-tone average hearing thresholds over time and the incidence of adverse events. RESULTS: In the IGF-1 group, 66.7% (95% confidence interval [CI], 52.9-78.6%) of the patients showed hearing improvement compared to 53.6% (95% CI, 39.7-67.0%) of the patients in the Dex group (P = 0.109). The difference in changes in pure-tone average hearing thresholds over time between the two treatments was statistically significant (P = 0.003). No serious adverse events were observed in either treatment group. Tympanic membrane perforation did not persist in any patient in the IGF-1 group, but did persist in 15.5% (95% CI, 7.3-27.4%) of the patients in the Dex group (P = 0.001). CONCLUSIONS: The positive effect of topical IGF-1 application on hearing levels and its favorable safety profile suggest utility for topical IGF-1 therapy in patients with sudden deafness. TRIAL REGISTRATION: UMIN Clinical Trials Registry Number UMIN000004366, October 30th, 2010.

Visual Field Improvement and Electrode Extrusion Prevention by Extended Endaural Incision With Cavity Obliteration for Cochlear Implantation in Ears After Canal Wall-Down Mastoidectomy: Experience of Four Cases.

There is no global consensus on the surgical technique of cochlear implantation (CI) in ears with an open cavity after canal wall-down (CWD) mastoidectomy. Here, we report CI surgery with an endaural incision for the ears after CWD mastoidectomy. The endaural incision was extended upward to obliterate the open cavity of the temporal fascial flap. The endaural incision was extended downward to close the open cavity inlet. After inserting the implanted electrode, the open cavity was obliterated using a temporal fascial flap, and the cavity was closed at the inlet. We performed this type of CI surgery in four ears in three patients. This extended endaural incision provided an excellent view for pedicling the temporal fascial flap with the superficial temporal artery and for open cavity closure without any serious complications. This technique allowed us to opt for CI surgery of the ears after CWD mastoidectomy.

Predicting lymph node recurrence in cT1-2N0 tongue squamous cell carcinoma: collaboration between artificial intelligence and pathologists.

Researchers have attempted to identify the factors involved in lymph node recurrence in cT1-2N0 tongue squamous cell carcinoma (SCC). However, studies combining histopathological and clinicopathological information in prediction models are limited. We aimed to develop a highly accurate lymph node recurrence prediction model for clinical stage T1-2, N0 (cT1-2N0) tongue SCC by integrating histopathological artificial intelligence (AI) with clinicopathological information. A dataset from 148 patients with cT1-2N0 tongue SCC was divided into training and test sets. The prediction models were constructed using AI-extracted information from whole slide images (WSIs), human-assessed clinicopathological information, and both combined. Weakly supervised learning and machine learning algorithms were used for WSIs and clinicopathological information, respectively. The combination model utilised both algorithms. Highly predictive patches from the model were analysed for histopathological features. In the test set, the areas under the receiver operating characteristic (ROC) curve for the model using WSI, clinicopathological information, and both combined were 0.826, 0.835, and 0.991, respectively. The highest area under the ROC curve was achieved with the model combining WSI and clinicopathological factors. Histopathological feature analysis showed that highly predicted patches extracted from recurrence cases exhibited significantly more tumour cells, inflammatory cells, and muscle content compared with non-recurrence cases. Moreover, patches with mixed inflammatory cells, tumour cells, and muscle were significantly more prevalent in recurrence versus non-recurrence cases. The model integrating AI-extracted histopathological and human-assessed clinicopathological information demonstrated high accuracy in predicting lymph node recurrence in patients with cT1-2N0 tongue SCC.

Extracting interpretable features for pathologists using weakly supervised learning to predict p16 expression in oropharyngeal cancer.

One drawback of existing artificial intelligence (AI)-based histopathological prediction models is the lack of interpretability. The objective of this study is to extract p16-positive oropharyngeal squamous cell carcinoma (OPSCC) features in a form that can be interpreted by pathologists using AI model. We constructed a model for predicting p16 expression using a dataset of whole-slide images from 114 OPSCC biopsy cases. We used the clustering-constrained attention-based multiple-instance learning (CLAM) model, a weakly supervised learning approach. To improve performance, we incorporated tumor annotation into the model (Annot-CLAM) and achieved the mean area under the receiver operating characteristic curve of 0.905. Utilizing the image patches on which the model focused, we examined the features of model interest via histopathologic morphological analysis and cycle-consistent adversarial network (CycleGAN) image translation. The histopathologic morphological analysis evaluated the histopathological characteristics of image patches, revealing significant differences in the numbers of nuclei, the perimeters of the nuclei, and the intercellular bridges between p16-negative and p16-positive image patches. By using the CycleGAN-converted images, we confirmed that the sizes and densities of nuclei are significantly converted. This novel approach improves interpretability in histopathological morphology-based AI models and contributes to the advancement of clinically valuable histopathological morphological features.

c-Ret-mediated hearing loss in mice with Hirschsprung disease.

A significantly increased risk for dominant sensorineural deafness in patients who have Hirschsprung disease (HSCR) caused by endothelin receptor type B and SOX10 has been reported. Despite the fact that c-RET is the most frequent causal gene of HSCR, it has not been determined whether impairments of c-Ret and c-RET cause congenital deafness in mice and humans. Here, we show that impaired phosphorylation of c-Ret at tyrosine 1062 causes HSCR-linked syndromic congenital deafness in c-Ret knockin (KI) mice. The deafness involves neurodegeneration of spiral ganglion neurons (SGNs) with not only impaired phosphorylation of Akt and NF-kappaB but decreased expression of calbindin D28k in inner ears. The congenital deafness involving neurodegeneration of SGNs in c-Ret KI mice was rescued by introducing constitutively activated RET. Taken together with our results for three patients with congenital deafness with c-RET-mediated severe HSCR, our results indicate that c-Ret and c-RET are a deafness-related molecule in mice and humans.

Endoscopic observation of pharyngeal mucosal suture healing process after total laryngectomy: case series.

BACKGROUND: Pharyngocutaneous fistula (PCF), a major complication of total laryngectomy, is caused by pharyngeal repair failure. OBJECTIVE: Assess the usefulness of endoscopic observation of the pharyngeal suture's healing process for the early detection of PCF development. METHODS: Pharyngeal mucosal sutures were endoscopically observed postoperatively in patients who underwent total laryngectomy with primary closure. RESULTS: Postoperatively, a white coat adhered to the pharyngeal mucosal suture of all patients. In most cases, the white coat gradually receded, which was considered to be a normal healing process. Thickening of the white coat and/or dehiscence of surgical wound were interpreted as 'poor healing conditions'. Three cases were judged to have developed poor healing conditions of the pharyngeal mucosal suture and one patient developed PCF. The other two patients did not develop PCF, possibly due to early detection of 'poor healing condition' and conservative approach, such as discontinuation of oral intake. CONCLUSIONS: Postoperative poor healing conditions of the pharyngeal mucosal suture may be precursors to PCF development. Endoscopic observation enables early detection of these conditions and may enable the prevention of PCF.

Estradiol protects hair cells from cisplatin-induced ototoxicity via Nrf2 activation.

Cisplatin-induced ototoxicity is caused by reactive oxygen species. It has been recognized that estradiol (E2) regulates redox balance. However, little is known about the protective mechanisms of E2 against cisplatin-induced ototoxicity. In this study, we investigated the effect of E2 on nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated hair cell protection using the organ of Corti isolated from mice. The organ of Corti collected from C57BL/6 mice at 3-5 postnatal days was used in all experiments. The organ of Corti was exposed to 20 µM cisplatin with/without 100 nM E2 to examine the effect of E2 on cisplatin-induced hair cell loss. The mRNA expression of Nrf2 and the phase II detoxification gene after E2 and cisplatin treatment was analyzed using quantitative real-time PCR. E2 significantly reduces cisplatin-induced cochlear hair cell death. In addition, 100 nM E2 increased the mRNA expression of Nrf2 and phase II detoxification genes in the organ of Corti under cisplatin treatment. Our results suggest that E2 activates Nrf2, phase II detoxification enzymes and exerts a protective effect against cisplatin-induced ototoxicity.

Successful Treatment of Basaloid Squamous Cell Carcinoma of the Nasal Cavity With Brain Invasion.

Basaloid squamous cell carcinoma (BSCC) is a rare and aggressive subtype of squamous cell carcinoma (SCC). To date, no consensus on the treatment of BSCC has been established yet, especially in cases of invasion of the skull base. In addition, long-term prognosis has not been reported in T4b cases. Herein, we report the case of a 36-year-old Japanese man with locally advanced nasal BSCC that directly invaded the skull base and the brain. The patient was then treated with induction chemotherapy (IC). Owing to his good response to IC, we planned and performed en bloc resection followed by adjuvant proton beam therapy (PBT). Follow-up examinations five years after treatment showed no evidence of recurrence. This is the first report of IC followed by radical surgery and adjuvant PBT in a patient with T4b. IC has the potential to play an important role in treatment strategies.

Development of Monoclonal Antibodies Specific to Either CD300AR111 or CD300AQ111 or Both.

CD300A is a member of the CD300 immunoglobulin (Ig)-like receptor family consisting of eight molecules in humans, all of which contain one Ig-like domain in the extracellular portion. Upon binding its ligand phosphatidylserine or phosphatidylethanolamine, CD300A mediates an inhibitory signal through the immunoreceptor tyrosine-based inhibitory motif in the cytoplasmic portion. The CD300 family molecules are highly homologous to each other. In addition, CD300A has a single nucleotide polymorphism (rs2272111), which is a nonsense mutation encoding glutamine (CD300AQ111) instead of arginine (CD300AR111) at residue 111 in the Ig-like domain of CD300A. In this study, we successfully generated monoclonal antibodies (mAbs) specific to either CD300AR111 or CD300AQ111 or both. These mAbs are useful for the analysis of CD300A genotype by flow cytometry and the development of an antibody drug for the treatment of various diseases.

Elevation of C-reactive protein during concurrent chemoradiotherapy is a poor predictive factor for head and neck cancer.

OBJECTIVE: The prognostic role of pretreatment C-reactive protein (CRP) has been reported for head and neck cancer. However, little is known about the relationship between the changes in CRP levels during treatment and prognosis. This study aimed to investigate the correlation between CRP elevation during concurrent chemoradiotherapy (CCRT) and survival outcomes. METHODS: The medical records of patients with oropharyngeal, hypopharyngeal, and laryngeal cancer treated with CCRT at the University of Tsukuba Hospital and National Hospital Organization Mito Medical Center from April 2014 to December 2019 were retrospectively reviewed. Patients were divided into normal (<0.3 mg/dl) and elevated (≥0.3 mg/dl) CRP groups according to the CRP level after the first cycle of cisplatin. The primary endpoint was progression-free survival (PFS). RESULTS: A total of 74 patients were enrolled, of whom 36 (49%) showed elevated CRP levels after the first cycle of cisplatin. The 3-year PFS was 83.3% and 61.0% in the normal and elevated CRP groups, respectively, showing significant differences between the two groups. CONCLUSION: Elevated CRP levels after the first cycle of cisplatin is an objective predictive marker for survival in patient with head and neck squamous cell carcinoma treated with CCRT.

Proton beam therapy in multimodal treatment for locally advanced squamous cell carcinoma of the nasal cavity and paranasal sinus.

BACKGROUND: To evaluate proton beam therapy (PBT) in multimodal treatment for locally advanced squamous cell carcinoma of the nasal cavity and paranasal sinus (NPSCC). METHODS: The cases in this study included T3 and T4 NPSCC without distant metastases that were treated at our center using PBT between July 2003 and December 2020. These cases were classified into 3 groups based on resectability and treatment strategy: surgery followed by postoperative PBT (group A); those indicated to be resectable, but the patient refused surgery and received radical PBT (group B); and those declared unresectable based on the extent of the tumor and treated with radical PBT (group C). RESULTS: The study included 37 cases, with 10, 9 and 18 in groups A, B and C, respectively. The median follow-up period in surviving patients was 4.4 years (range 1.0-12.3 years). The 4-year overall survival (OS), progression-free survival (PFS), and local control (LC) rates were 58%, 43% and 58% for all patients; 90%, 70% and 80% in group A, 89%, 78% and 89% in group B; and 24%, 11% and 24% in group C. There were significant differences in OS (p = 0.0028) and PFS (p = 0.009) between groups A and C; and in OS (p = 0.0027), PFS (p = 0.0045) and LC (p = 0.0075) between groups B and C. CONCLUSIONS: PBT gave favorable outcomes in multimodal treatment for resectable locally advanced NPSCC, including surgery followed by postoperative PBT and radical PBT with concurrent chemotherapy. The prognosis for unresectable NPSCC was extremely poor, and reconsideration of treatment strategies, such as more active use of induction chemotherapy, may improve outcomes.

Effect of Average Relative Humidity on Epistaxis.

Background Epistaxis is a very common symptom. The occurrence of epistaxis may be affected by dry environments, but there are some differences among previous reports and this view is controversial. Objective We investigated the relationship between the number of epistaxes and daily average relative humidity. Methods Data on patients with epistaxis between March 2011 and February 2021 were collected from two hospitals. The daily average relative humidity was examined, and the change in the number of patients with epistaxis due to humidity was investigated using a generalized linear mixed model. Results A total of 4184 cases of epistaxis were identified. The number of epistaxis cases per day was significantly associated with the daily average relative humidity (p < 0.001). One percent increment in average relative humidity decreases the number of epistaxis cases per day by 1.1%. Conclusion A negative correlation was found to exist between daily average relative humidity and occurrences of epistaxis.