A Case Found to Be Severe Acute Respiratory Syndrome Coronavirus 2 Positive Immediately Before Hospitalization for Infectious Mononucleosis.

The cases of coronavirus disease 2019 (COVID-19) mainly present with symptoms such as persistent fever, cough, and general malaise, which may become severe or fatal; while young people do not show these typical symptoms and are asymptomatic, some cases are infected with minor symptoms or none. Herein, we report a case of a 20-year-old woman who was hospitalized for infectious mononucleosis (IM). Initially, fever and sore throat were observed without typical COVID-19 symptoms, but polymerase chain reaction (PCR) tests performed before admission confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positivity. Fortunately, she was discharged without any serious symptoms as IM and COVID-19. Virological examination suggested a primary infection with the Epstein-Barr virus. In the COVID-19 pandemic, we should also pay attention to the possibility of SARS-CoV-2 coinfection in mild and asymptomatic young cases, even if the symptoms suggesting IM are preceded.

A Case of Carcinoid Tumors in the Ear Canal With Long-Term Postoperative Follow-Up.

Carcinoid tumors in the ear canal are very rare. In this report, we experienced a case of carcinoid tumor of the ear canal that underwent total tumor resection. This study included a 39-year-old man presented with a chief complaint of right-sided hearing loss. Computed tomography scan showed a shadow from the ear canal to the right tympanic chamber. There were no suspicious findings of metastasis in the cervical lymph nodes or other organs. At the time of surgery, the tumor was simply removed because it was small and there was no adhesive invasion. Postoperatively, the patient has been under observation for 11.5 years without any recurrence. Carcinoid tumors in the ear canal can rarely metastasize or recur after more than 10 years. It is important to follow up with the patient for a long time after surgery, using the Ki-67 index of the removed tissue as a prognostic reference.

Third Epidemiological Analysis of Nasopharyngeal Carcinoma in the Central Region of Japan from 2006 to 2015.

The present study aimed to clarify the incidence and clinical outcomes of nasopharyngeal carcinoma (NPC) in the Chubu region of Japan from 2006 to 2015, compared with previous reports. A retrospective analysis was conducted based on medical records from 40 hospitals located in the Chubu region in the central Japanese main island, with a population of around 22.66 million individuals. This study was designed in line with to two previous clinical studies into NPC conducted in the same area of Japan. We recruited NPC patients diagnosed in hospitals across this area over a 10-year period (2006-2015) using a questionnaire about sex, age, primary site, clinical symptoms, pathology, Union for International Cancer Control (UICC) staging, serological exam, treatment, and survival. A total of 620 NPC patients were identified. The age-standardized incidence of NPC from 2006 to 2015 was 0.27 per 100,000 individuals per year. There were no significant differences between this study and the previous two studies conducted in the same area of Japan. The five-year overall survival rate for all patients was 75.9%, while those for patients with stages I, II, III, and IVA were 97%, 91%, 79%, and 68%, respectively. The age-standardized annual incidence of NPC in the present study was 0.27 per 100,000 individuals per year, which was relatively low and stable. The five-year overall survival rate for all NPC patients was significantly improved in this decade compared with previous studies. The smoking rates in male and female NPC patients were 64.5% and 18.8%, respectively, thereby suggesting the involvement of smoking in the incidence of NPC.

Galectin-1 enhances the generation of neural crest cells.

Neural crest (NC) cells are multipotent cells that emerge from the dorsal region of the neural tube. After delaminating from the neural tube, NC cells migrate throughout the developing embryo and differentiate into various cells: neurons and glial cells of the peripheral nervous system, melanocytes of skin, and skeletal elements of the face and head. We previously analyzed the gene expression profile of a NC subpopulation isolated from Sox10-IRES-Venus mice and found that the carbohydrate-binding protein, Galectin-1 (Gal-1) was strongly expressed in generating NC cells. In the present study, we identified GAL-1 as a factor that promotes NC cell generation. Gal-1 was significantly expressed in NC cells generated in explanted neural tubes. The presence of GAL-1 enhanced the generation of NC-like cells from mouse embryonic stem (ES) cells. In the differentiation of ES cells into NC-like cells, GAL-1 enhanced neurogenesis in the early stages and facilitated NC-like cell generation in the later stages. GAL-1 also enhanced the generation of NC cells from explanted neural tubes. These results suggest that GAL-1 plays a facilitative role in NC cell generation.

[Eight Cases of Small Cell Neuroendocrine Carcinoma of the Head and Neck].

Small cell neuroendocrine carcinoma of the head and neck is a rarely occurring poorly differentiated and high-grade malignant neoplasm characterized by highly active proliferation of neuroendocrine tumor cells. There are no established therapies for this disease. To clarify the clinical course and develop effective treatment(s) for the carcinoma, we reviewed the data of 8 patients of small cell neuroendocrine carcinoma of the head and neck treated by us between 2006 and 2014 at the Department of Otolaryngology, Gifu University School of Medicine and our affiliated hospitals. The patients consisted of 3 men and 5 women, ranging in age from 38 to 84 years old (mean : 60.9 years). The tumor arose from the nasal cavity or the paranasal sinuses in 3 cases, from the parotid grand in 2 cases, from the oropharynx in 2 cases, and from the hypopharynx in 1 case. The tumor that arose from the hypopharynx was a combined small-cell carcinoma with squamous cell carcinomas, and the one that arose from the oropharynx had already metastasized to the brain. Most of the patients were treated by chemotherapy and radiotherapy based on the treatment employed for small cell carcinoma of the lung. Only the patient in whom the tumor arose from a paranasal sinus was treated by surgery despite the definitive diagnosis of small cell carcinoma. We selected CPT-11 and a platinum agent for 4 patients, and VP-16 and a platinum agent for 3 patients as the first-line chemotherapy. Although two patients showed carcinoma-free survival, one died of recurrence of the regional lymph node metastases and five died of distant metastases despite the absence of locoregional recurrence. The 5-year survival rate was a dismal 25%, suggesting that we need to establish effective treatment(s) for the control of distant metastases in cases of the small cell neuroendocrine carcinoma of the head and neck.

Neural crest-derived cells sustain their multipotency even after entry into their target tissues.

BACKGROUND: Neural crest cells (NC cells) are highly migratory multipotent cells. Their multipotency is transient at the early stage of their generation; soon after emerging from the neural tube, these cells turn into lineage-restricted precursors. However, recent studies have disputed this conventionally believed paradigm. In this study, we analyzed the differentiation potency of NC-derived cells after their arrival at target tissues. RESULTS: Using Sox10-IRES-Venus mice, we found that the NC-derived cells in the skin, DRG, and inner ear could be divided into two populations: Sox10-positive/Kit-negative cells (Sox10+/Kit- cells) and Sox10- and Kit-positive cells (Sox10+/Kit+ cells). Only the Sox10+/Kit- cells were detected in the intestines. Unexpectedly, the Sox10+/Kit+ cells differentiated into neurons, glial cells, and melanocytes, showing that they had maintained their multipotency even after having entered the target tissues. The Sox10+/Kit+ cells in the DRG maintained their multipotency for a restricted period during the earlier embryonic stages, whereas those in the skin and inner ear were multipotent yet even in later embryonic stages. CONCLUSIONS: We showed that NC-derived Sox10+/Kit+ cells maintained their multipotency even after entry into the target tissues. This unexpected differentiation potency of these cells in tissues seems to have been strictly restricted by the tissue microenvironment.

The association between impaired perception of verticality and cerebral white matter lesions in the elderly patients with orthostatic hypotension.

BACKGROUND: The morbidity of orthostatic hypotension (OH) increases with aging and the elderly often complain of dizziness associated with OH, which is implicated in white matter lesions (WMLs) on MRI. However little is known how WMLs are contributed to the development of dizziness in elderly patients. OBJECTIVE: We evaluated the involvement of cerebral WMLs in the vertical perception in the elderly with OH. METHODS: This study consisted of 71 dizzy patients who underwent the examinations including the Schellong orthostatic test and subjective visual vertical (SVV) test. RESULTS: The male patients aged <65 years with OH (1.9 ± 0.9°) showed a significantly higher magnitude of variance of SVV, which reflects an impaired vertical perception, in comparison with the male patients aged <65 years without OH and the male patients aged < 65 years with OH (1.0 ± 0.4°, 0.9 ± 0.4°, p < 0.05). The variance of SVV significantly correlated with the volume of WMLs in both sides on MRI in the male, but not female patients (p < 0.01). CONCLUSIONS: Our results suggest that severe WMLs in the elderly with OH are involved in impaired perception of verticality, resulting in inducing subjective dizziness.

Tracing Sox10-expressing cells elucidates the dynamic development of the mouse inner ear.

The inner ear is constituted by complicated cochlear and vestibular compartments, which are derived from the otic vesicle, an embryonic structure of ectodermal origin. Although the inner ear development has been analyzed using various techniques, the developmental events have not been fully elucidated because of the intricate structure. We previously developed a Sox10-IRES-Venus mouse designed to express green fluorescent protein under the control of the Sox10 promoter. In the present study, we showed that the Sox10-IRES-Venus mouse enabled the non-destructive visualization and understanding of the morphogenesis during the development of the inner ear. The expression of the transcription factor Sox10 was first observed in the invaginating otic placodal epithelium, and continued to be expressed in the mature inner ear epithelium except for the hair cells and mesenchymal cells. We found that Sox10 was expressed in immature hair cells in the developing inner ear, suggesting that hair cells were generated from the Sox10-expressing prosensory cells. Furthermore, we demonstrated that scattered Sox10-expressing cells existed around the developing inner ear, some of which differentiated into pigmented melanocytes in the stria vascularis, suggesting that they were neural crest cells. Further analyzing the Sox10-IRES-Venus mice would provide important information to better understand the development of the inner ear.

Dual origin of melanocytes defined by Sox1 expression and their region-specific distribution in mammalian skin.

Melanocytes are pigment-producing cells generated from neural crest cells (NCCs) that delaminate from the dorsal neural tube. The widely accepted premise that NCCs migrating along the dorsolateral pathway are the main source of melanocytes in the skin was recently challenged by the finding that Schwann cell precursors are the major cellular source of melanocytes in the skin. Still, in a wide variety of vertebrate embryos, melanocytes are exclusively derived from NCCs. In this study, we show that a NCC population that is not derived from Sox1(+) dorsal neuroepithelial cells but are derived from Sox1(-) cells differentiate into a significant population of melanocytes in the skin of mice. Later, these Sox1(-) cells clearly segregate from cells that originated from Sox1(+) dorsal neuroepithelial cell-derived NCCs. The possible derivation of Sox1(-) cells from epidermal cells also strengthens their non-neuroepithelial origin.

Damping control of balance in the medial/lateral direction and the risk of falling in the elderly.

AIMS: A proportional-integral-derivative (PID) control has recently been used as a control algorithm of body balance. The purpose of this study was to elucidate an association of the proportional and derivative gain based on the PID control gain for balance for quiet standing with the risk factor for falls in the elderly. METHODS: The movement of a marker on the back of 23 elderly participants (age 75.6±6.6 years) was measured by our developed device with a complementary metal oxide semiconductor video camera and the trunk sway speed in the medial/lateral (M/L) direction (TSSX) was calculated as absolute values of the whole time series. The PID control gain (proportional gain: K(P), integral gain: K(I), derivative gain: K(D)) was identified using the trunk sway data, and normalized by individual height and weight (K(P)n, K(D)n and K(I)n). Individual risk factor for falls was additionally assessed with the Tinetti Performance Oriented Mobility Assessment (POMA) and the fall risk questionnaire. RESULTS: The score in the POMA and the K(D)n significantly decreased with age (P<0.01). The score in the POMA showed a positive correlation with the K(D)n, and negative correlations with the TSSX and K(P)/K(D) ratios (P<0.01). The average K(D)n and the score in the POMA of fallers were significantly lower than those of non-fallers (P<0.05). CONCLUSION: These results suggest that the decreased damping control by derivative gain for balance in the M/L direction is one of the risk factors for falls in the elderly.