Effects of irradiation on cumulative mortality in mice: shifting toward a younger age of death.

Recently, the question of whether cancer risk is only accelerated but not increased by radiation exposure has been raised. To explore this matter, we analyzed whether the cumulative mortality of irradiated mice could be explained by x-axis (age) shifted cumulative mortality of nonirradiated mice. We reanalyzed publicly available data on observed cumulative mortality or prevalence in irradiated female B6C3F1 mice that lived their entire lifespan. The results showed that the irradiated curve was well matched to uniformly shifted nonirradiated curve for the cumulative mortality of all causes of death but not for the cumulative mortality of all solid tumors and prevalence of ovarian tumors as is. After adjusting lifetime mortalities, it was also well matched for all solid and ovarian tumors. The shifted days by irradiation were 71-116 days for all causes of death, 56-135 days for all solid tumors, and 41-140 days for ovarian tumors in the 1.9 Gy-irradiated group. The response was switched between irradiation at 35 and 105 days consistently for all the above indexes, supporting the hypothesis that radiation sensitivity differs between juvenile and adults. The shifted days of all causes of death showed a tendency of linear response to dose. This concept of shifting the age of death can be applied not only for all cause of death but also for mortality of all solid tumors after adjusting the magnitude. These findings contribute to the discussion on the application of the 'shifting age of death' concept to radiation protection.

A multicenter, double-blind, randomized, parallel-group, placebo-controlled study to evaluate the efficacy and safety of camostat mesilate in patients with COVID-19 (CANDLE study).

BACKGROUND: In vitro drug screening studies have indicated that camostat mesilate (FOY-305) may prevent SARS-CoV-2 infection into human airway epithelial cells. This study was conducted to investigate whether camostat mesilate is an effective treatment for SARS-CoV-2 infection (COVID-19). METHODS: This was a multicenter, double-blind, randomized, parallel-group, placebo-controlled study. Patients were enrolled if they were admitted to a hospital within 5 days of onset of COVID-19 symptoms or within 5 days of a positive test for asymptomatic patients. Severe cases (e.g., those requiring oxygenation/ventilation) were excluded. Patients were enrolled, randomized, and allocated to each group using an interactive web response system. Randomization was performed using a minimization method with the factors medical institution, age, and underlying diseases (chronic respiratory disease, chronic kidney disease, diabetes mellitus, hypertension, cardiovascular diseases, and obesity). The patients, investigators/subinvestigators, study coordinators, and other study personnel were blinded throughout the study. Patients were administered camostat mesilate (600 mg qid; four to eight times higher than the clinical doses in Japan) or placebo for up to 14 days. The primary efficacy endpoint was the time to the first two consecutive negative tests for SARS-CoV-2. RESULTS: One-hundred fifty-five patients were randomized to receive camostat mesilate (n = 78) or placebo (n = 77). The median time to the first test was 11.0 days (95% confidence interval [CI]: 9.0-12.0) in the camostat mesilate group and 11.0 days (95% CI: 10.0-13.0) in the placebo group. Conversion to negative viral status by day 14 was observed in 45 of 74 patients (60.8%) in the camostat mesilate group and 47 of 74 patients (63.5%) in the placebo group. The primary (Bayesian) and secondary (frequentist) analyses found no significant differences in the primary endpoint between the two groups. No additional safety concerns beyond those already known for camostat mesilate were identified. CONCLUSIONS: Camostat mesilate did not substantially reduce the time to viral clearance, based on upper airway viral loads, compared with placebo for treating patients with mild to moderate SARS-CoV-2 infection with or without symptoms. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04657497. Japan Registry for Clinical Trials, jRCT2031200198.

The significance of thermomechanical processing on the cellular response of biomedical Co-Cr-Mo alloys.

Strengthening of biomedical Co-Cr-Mo alloys has been explored via thermomechanical processing for enhancing the durability of their biomedical applications. However, the effects of cold and hot deformation on the cellular activity continue to be unclear. In this study, we prepared Co-Cr-Mo alloy rods via cold swaging and hot-caliber rolling and studied the relationship between the microstructure and cellular response of pre-osteoblasts. The cold-swaged rod experienced strain-induced martensitic transformation, which increased the volume fraction of the hexagonal close-packed (hcp) ε-martensite to ∼60 vol.% with an increase in area reduction (r) to 30%. The 111γ fiber texture of the face-centered cubic (fcc) γ-matrix followed the Shoji-Nishiyama orientation relationship with ε-martensite. Cell culture results revealed beneficial effects of cold swaging on the cell response, in terms of adhesion, proliferation and morphology of cells, although increasing r did not significantly affect cellular metabolism levels. The addition of small content of Zr (0.04 wt.%) led to enhanced focal adhesion of cells, which became more significant at higher r. The microstructural evolution during hot-caliber rolling, namely, grain refinement without any phase transformation and strong texture development, did not appreciably affect the cellular activity. These findings are envisaged to facilitate alloy design and microstructural optimization for favorable tuning the osseointegration of biomedical Co-Cr-Mo alloys.

Pleural and pulmonary metastases from nonseminomatous germ cell tumors successfully managed by extrapleural pneumonectomy.

INTRODUCTION: Surgery for postchemotherapy residual nonseminomatous germ cell tumors may be difficult due to exceptional lesion size and location. CASE PRESENTATION: A 47-year-old man presented with swelling and pain in the left scrotum. Computed tomography revealed a solid occupied lesion in the left scrotum with huge metastases in the left lung and pleura. Results of a left high inguinal orchiectomy indicated a pathological diagnosis of germ cell tumors of several histological types. The patient declined postoperative chemotherapy but returned to our department 10 months later with dyspnea. Serum tumor marker levels were restored to normal range by adjuvant chemotherapy. Thereafter, an extrapleural pneumonectomy was performed for the remaining tumors. He has since been asymptomatic without recurrence or dyspnea for over 5 years. CONCLUSION: Extrapleural pneumonectomy is a valid treatment option for the management of huge pleural and pulmonary metastases of nonseminomatous germ cell tumors.

Long-term safety and efficacy of opicapone in Japanese Parkinson's patients with motor fluctuations.

The double-blind part of the COMFORT-PD (COMt-inhibitor Findings from Opicapone Repeated Treatment for Parkinson's Disease) study in Japanese levodopa-treated patients with Parkinson's disease and motor fluctuations found that both opicapone 25 and 50 mg were significantly more effective than placebo. This 52-week open-label extension study evaluated the long-term safety and efficacy of opicapone 50 mg tablets in patients who completed the double-blind part of the COMFORT-PD study. Safety was monitored via adverse events, laboratory testing, and physical, cardiovascular and neurological examinations. Efficacy was primarily assessed by change in OFF-time. Secondary efficacy measures included: ON-time, percentage of OFF/ON-time responders, other outcomes from the double-blind part. 391/437 patients were transferred to the open-label extension period and included in the safety analysis set (full analysis set, n = 387; open-label completers, n = 316). Adverse events were frequently reported (n = 338, 86.4%), but < 50% were considered drug-related (39.9%) and few were considered serious (2.6%) or led to discontinuation (2.8%). Decreased OFF-time was consistently observed over the open-label period regardless of initial randomization. Change [LSM (SE)] in OFF-time from the open-label baseline to the last visit showed a persistent effect in patients initially randomized to opicapone 25 mg [- 0.37 (0.20) h, P = 0.0689] and opicapone 50 mg [- 0.07 (0.21) h, P = 0.6913] whereas opicapone 50 mg led to a statistically significant reduction in the previous placebo group [- 1.26 (0.19) h, P < 0.05]. Once-daily opicapone 50 mg was generally well tolerated and consistently reduced OFF-time over 52 weeks in Japanese levodopa-treated patients with motor fluctuations.Trial registration JapicCTI-153112; date of registration: December 25, 2015.

Randomized, Controlled Study of Opicapone in Japanese Parkinson's Patients with Motor Fluctuations.

OBJECTIVES: This placebo-controlled, randomized study evaluated the efficacy and safety of opicapone 25-mg and 50-mg tablets in Japanese levodopa-treated patients with Parkinson's disease and motor fluctuations. METHODS: Japanese adults (n = 437, age 39-83 years) with Parkinson's disease (United Kingdom Parkinson's Disease Society criteria) received opicapone 25-mg (n = 145), opicapone 50-mg (n = 145), or placebo (n = 147) tablets over the double-blind treatment period (14-15 weeks). The primary efficacy assessment was change in OFF-time; secondary efficacy assessments included OFF/ON-time responders (≥1 hour change from baseline), total ON-time, ON-time with and without troublesome dyskinesia, and Unified Parkinson's Disease Rating Scale. RESULTS: The least squares mean (standard error) change in OFF-time from baseline to the last visit was -0.42 (0.21) hour for the placebo group, -1.16 (0.22) hour for the opicapone 25 mg group, and -1.04 (0.21) hour for the opicapone 50 mg group. The percentage of ON-time responders, changes in total ON-time/ON-time without troublesome dyskinesia, and Unified Parkinson's Disease Rating Scale II (at OFF) all showed statistically significant improvements versus placebo for both opicapone tablet doses (P < 0.05). Unified Parkinson's Disease Rating Scale III (at ON) was improved versus placebo in patients who received opicapone 50 mg (P < 0.05). Adverse events were more common in patients treated with opicapone 25 mg (60.0%) or opicapone 50 mg (54.5%) versus placebo (48.3%). The most commonly reported adverse event was dyskinesia (placebo, 2.7%; opicapone 25 mg, 9.0%; opicapone 50 mg, 12.4%). CONCLUSIONS: In Japanese patients, both opicapone 25 and 50 mg were significantly more effective than placebo with no dose-dependent difference in efficacy, and both doses were well tolerated. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Clinical features and prognostic impact of coexisting autoimmune disease other than myasthenia gravis in resected thymomas: analysis of a Japanese multi-institutional retrospective database.

OBJECTIVES: The purpose of this study was to clarify the prevalence, clinical features and survival of patients with thymoma and non-myasthenia gravis autoimmune disease (NMAD) using a nationwide cohort. METHODS: The Japanese Association for Research on the Thymus nationwide database, which includes data from 32 institutions, was examined to clarify the prevalence and characteristics of NMAD associated with thymomas and elucidate the prognostic impact of NMAD for thymoma patients. RESULTS: Among the 2423 patients with thymomas who were surgically treated between 1991 and 2010, 114 (4.7%) were identified with NMAD. The most frequently observed NMAD was pure red cell aplasia (PRCA) in 44 (1.8%), followed by hypogammaglobulinaemia (0.5%) and rheumatic arthritis (0.5%). Twenty-eight percent of patients with NMAD had concomitant myasthenia gravis. The presence of NMAD was not an independent prognostic factor for overall survival (OS) irrespective of the type of NMAD [PRCA+: hazard ratio (HR) 1.99, 95% confidence interval 0.74-4.47; PRCA- NMAD: HR 1.28, 0.30-3.56]; however, there were more cases with advanced age and disease of the thymoma amongst PRCA+ patients and these showed a worse OS than patients with PRCA- NMAD (P < 0.001), who had an OS similar to those without NMAD (P = 0.489). The 10-year OS rates in PRCA+, PRCA- NMAD and NMAD- groups were 45.5%, 97.4% and 89.5%, respectively. The main causes of death in PRCA+ patients were the progression of thymoma and other diseases including pneumonia. CONCLUSIONS: Although the presence of NMAD itself did not significantly affect survival after surgery for thymoma, the type of NMAD was associated with different clinical features and prognosis. The NMAD+ thymomas should be separately categorized according to the presence or absence of PRCA.

A Mathematical Model for Stem Cell Competition to Maintain a Cell Pool Injured by Radiation.

The effect of low-dose-rate exposure to ionizing radiation on cancer risk is a major issue associated with radiation protection. Tissue stem cells are regarded as one of the targets of radiation-induced carcinogenesis. However, it is hypothesized that the effect of radiation may be reduced if damaged stem cells are eliminated via stem cell competition between damaged and intact stem cells. This would be particularly effective under very low-dose-rate conditions, in which only a few stem cells in a stem cell pool may be affected by radiation. Following this hypothesis, we constructed a simple mathematical model to discuss the influence of stem cell competition attenuating the accumulation of damaged cells under very low-dose-rate conditions. In this model, a constant number of cells were introduced into a cell pool, and the numbers of intact and damaged cells were calculated via transition and turnover events. A transition event emulates radiation dose, whereby an intact cell is changed into a damaged cell with a given probability. On the other hand, a turnover event expresses cell competition, where reproduction and elimination of cells occur depending on the properties of cells. Under very low-dose-rate conditions, this model showed that radiation damage to the stem cell pool was strongly suppressed when the damaged cells were less reproductive and tended to be eliminated compared to the intact cells. Furthermore, the size of the stem cell pool was positively correlated with reduction in radiation damage.

Posterior mediastinal ganglioneuroblastoma in an adolescent: A case report and review.

Ganglioneuroblastoma is an uncommon malignant tumor of the sympathetic nervous system, which is considered a disease of children with the majority of cases in patients less than four years old and it rarely occurs in adults. We encountered a very unusual case of a posterior mediastinal ganglioneuroblastoma that developed in a 17-year-old male adolescent who underwent successful excision of the mediastinal mass and remained stable postoperatively. However, he developed lumbago one year after the surgery. Radiographic findings revealed osteolytic lesions in the lumbar vertebra and histological analysis confirmed bone metastasis of ganglioneuroblastoma. Here, we report the clinical course and present a review of the literature regarding adolescent and adult onset mediastinal ganglioneuroblastoma.

Horizontal transmission of foot-and-mouth disease virus O/JPN/2010 among different animal species by direct contact.

Foot-and-mouth disease (FMD) is highly contagious and easily transmitted among species of cloven-hoofed animals. To investigate the transmission of FMD virus (FMDV) among different animal species, experimental infections using the O/JPN/2010 strain were performed in cows, goats and pigs. One cow or two goats/pigs were housed with a different species of inoculated animals, and clinical observations, virus shedding and antibody responses were analysed daily. Whilst all cows and goats were infected horizontally by contact with inoculated pigs, transmission from cows to goats/pigs and from goats to cows/pigs was not observed in all in-contact animals. In particular, no pigs were infected horizontally by contact with inoculated goats. Comparison with our previous study on experimental infections among animals of the same species indicates that horizontal transmission occurred more easily between animals of the same species than between those of the different species. These findings will be useful for establishing and performing species-specific countermeasures in farms and regions where multiple species of animals coexist in potential future outbreaks.

Development and evaluation of silver amplification immunochromatography kit for foot-and-mouth disease virus antigen detection.

A silver amplification immunochromatography (SAI) kit for the detection of all seven serotypes of foot-and-mouth disease virus (FMDV)-FMDV-Ag SAI-was developed using the monoclonal antibody 1H5 recognizing the highly conserved N terminus region of VP2. The FMDV-Ag SAI can be used under conditions of high biosecurity containment as it does not require any apparatus. The FMDV-Ag SAI exhibited 10-100 times higher sensitivity against the five serotypes (O, A, Asia1, C, and SAT1) and similar sensitivity against SAT2 and SAT3, compared with the Svanodip® FMDV-Ag kit immunochromatography kit. The Svanodip kit showed inhibitory results with several saliva samples but not with the FMDV-Ag SAI kit. In a validation study using clinical samples (n = 132; vesicular epithelium = 92, vesicular lesion swabs = 20, saliva = 20) in Mongolia, the sensitivity of FMDV-Ag SAI in comparison with real-time reverse transcription-polymerase chain reaction revealed the following data: vesicular epithelium, 85.4% (76/89); vesicular lesion swab, 46.7% (7/17); and saliva, 36.8% (7/19). No cross-reactivity with the non-FMDV vesicular-forming viruses and taxonomically related viruses of the Picornaviridae family occurred. The FMDV-Ag SAI is a highly sensitive diagnostic tool that enables pen-side diagnosis without requiring the use of any equipment.

Mortality from extrathymic malignancy after thymic tumour resections: incidences and risk factors.

OBJECTIVES: To identify risk factors associated with extrathymic malignancy-related mortality after thymic epithelial tumour resection. METHODS: The Japanese Association for Research on the Thymus database registered the records of 2835 patients collected from 32 Japanese institutions from 1991 to 2010. The cumulative incidence function of death due to extrathymic malignancies or recurrence was calculated, with other causes of death as competing risks. Relevant risk factors associated with extrathymic malignancy-related deaths in patients with thymoma were evaluated using the Fine and Gray model. RESULTS: In total, 2701 patients were eligible for the analysis (thymoma, 2374; thymic carcinoma, 273; thymic neuroendocrine tumour, 54). The median follow-up period was 4.6 years. The cumulative incidence function of death due to extrathymic malignancies at 10 years was 2.2% (3.2% due to recurrence) in patients with thymoma, 1.6% (38.6% due to recurrence) in patients with thymic carcinoma and 0% (36.6% due to recurrence) in patients with thymic neuroendocrine tumour. In the multivariable analysis, age (every 10 years) at thymectomy [hazard ratio (HR) 2.19, 95% confidence interval (CI) 1.53-3.14; P < 0.001], male gender (HR 2.62, 95% CI 1.19-5.77; P = 0.017) and previous malignancies (HR 3.09, 95% CI 1.18-8.11; P = 0.022) were significant factors for death due to extrathymic malignancies after thymectomy. CONCLUSIONS: Continued management and early detection of extrathymic malignancies may improve survival of patients with thymoma who are male, of advanced age, or have previous malignancies. Prospective studies are required to further investigate the management of extrathymic malignancies.

Tumour size determines both recurrence-free survival and disease-specific survival after surgical treatment for thymoma.

OBJECTIVES: The tumour, node and the metastasis (TNM) staging system for thymic epithelial tumours was adopted by the Union for International Cancer Control (UICC) in 2016. Although the T factor is defined by the invasive nature of a thymoma, tumour size is not considered. The aim of this study was to examine the clinical importance of tumour size using a nationwide retrospective database of cases treated from 1991 to 2010 compiled by the Japanese Association for Research of the Thymus. METHODS: Tumour size was evaluated by the maximum diameter shown by computed tomography imaging prior to resection. Tumour size was available for 2083 thymoma patients undergoing upfront surgical treatment. The tumour size ranged from 0.6 to 19.4 cm (mean 5.1 cm, median 4.9 cm). Harrell's C-index was adopted to determine the cut-off value of the tumour size in 0.5-cm increments. RESULTS: The highest C-index value (0.7760) was obtained in terms of recurrence-free survival after the complete resection when the cut-off value was set at 5.0 cm. The 10-year recurrence-free survival rate was 93.8% in patients with a tumour ≤5.0 cm and 84.3% in patients with a tumour >5.0 cm (P < 0.0001). The highest C-index value (0.8885) in terms of disease-specific survival was obtained when the cut-off value was set at 8.0 cm. The 10-year disease-specific survival rate was 98.8% in patients with a tumour <8.0 cm and 90.1% in those with a tumour ≥8.0 cm (P < 0.0001). The Cox's proportional hazard model analysis showed that the tumour size and the TNM-based pathological stage were independent factors to determine both recurrence-free survival and disease-specific survival. CONCLUSIONS: Tumour size is an important prognostic factor and should be considered when determining the treatment strategy for thymoma patients.

Thoracoscopic resection of a cystic seminoma of the mediastinum.

Mediastinal seminoma is an uncommon tumor that accounts for 25% of primary mediastinal germ cell tumors, which in turn comprise fewer than 5% of all germ cell tumors. Although CT normally shows a solid, lobulated tumor, mediastinal cystic seminoma has rarely been described. Here, we report a 24-year-old man who presented with a mediastinal cystic tumor that was resected after an 18-month delay via video-assisted thoracoscopic surgery while in the supine position; the procedure involved lifting the chest wall with a subcutaneous Kirschner wire. Pathological examination revealed a mediastinal cystic seminoma. No evidence of recurrence has been noted during 25 months of follow-up. Mediastinal cystic seminoma should be considered in the differential diagnosis of cystic lesions of the mediastinum. Moreover, video-assisted thoracoscopic resection may be an appropriate option for the diagnosis and treatment of such lesions.

Multiple primary chordomas of the lung.

We here report the case of a 40-year-old man with primary pulmonary chordomas. Although an abnormality had been noted on a chest radiograph at age 26 years, the patient had not undergone further examination at that time because he was asymptomatic. Standard chest radiographs and computed tomography showed slow-growing, multiple bilateral pulmonary nodules. Two tumors were resected thoracoscopically to obtain a diagnosis. Pathologic examination resulted in a diagnosis of chordomas. Subsequent systemic examination revealed no additional lesions, not even in the axial skeleton. The patient is alive without any new lesions 38 months after surgery. These clinical and pathological findings suggest that our patient has multiple primary chordomas of the lung, which is an extremely rare condition.

Pathogenesis of the attenuated foot-and-mouth disease virus O/JPN/2000 in experimentally infected pigs.

We examined the pathogenesis of the attenuated foot-and-mouth disease virus (FMDV) O/JPN/2000 in pigs. The virus used in this study was passaged three times in primary bovine kidney (BK) cells and once in baby hamster kidney-21 (BHK-21) cells after isolation. A plaque assay demonstrated that this virus exhibited the small plaque (SP) phenotype. There was no clinical or histological evidence of vesicular lesions in pigs intraorally inoculated with 106 50% tissue culture infectious dose (TCID50)/ml of the SP virus (SPV) of FMDV O/JPN/2000. Although fever was detected from 2 or 3 days post inoculation (dpi), there was no other prominent clinical sign up to 6 dpi. Virus shedding from saliva and nasal swab samples was not observed in any pigs inoculated with the SPV of FMDV O/JPN/2000. In the foot, mild lamellar degeneration of prickle cells in the upper layer of the stratum spinosum was histologically observed without development into vesicular or necrotic lesions. Immunohistochemical virus antigen- and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL)-positive reactions observed in the foot at 1 dpi seemed to disappear after 3 and 6 dpi. Our findings suggest that the SPV of FMDV O/JPN/2000 had low pathogenicity against pigs by intraoral inoculation.

Comparative evaluation of two ELISA kits for detecting antibodies to a nonstructural protein of foot-and-mouth disease virus using serum samples collected from naturally and experimentally infected cows.

When foot-and-mouth disease (FMD) occurs and a "vaccination-to-live" policy is adopted in a country, the country must perform serological surveillance of a nonstructural protein (NSP) of FMD virus. The NCPanaftosa kit is the only kit for detecting antibodies to NSPs that is officially recognized as the reference regent by the World Organization for Animal Health; however, it is only used in South American countries. In this study, the specificity and sensitivity of the NCPanaftosa kit were compared with those of the PrioCHECK kit sold by an international company. Results in this study suggest that the PrioCHECK kit performs similarly to the NCPanaftosa kit in detecting antibodies to the NSP in the cattle population.