Local conductance spectra of itinerant ferromagnetic SrRuO3 through break junction

We have measured the local differential conductance spectra (dI/dV-V) of an itinerant ferromagnet composed of polycrystalline SrRuO3 using the mechanically controllable break junction technique. Below the material's Curie temperature (T-C = 160 K), characteristic peak or dip conductance spectra are observed. The characteristic energy scale is comparable to the exchange spin splitting energy that is based on ferromagnetic band calculations. Both the peak and dip spectral shapes are explained based on the itinerant ferromagnetic characteristics of SrRuO3 in terms of spin-dependent transmission, which is similar to the giant magnetoresistance mechanism. (C) 2016 The Japan Society of Applied PhysicsArticleJAPANESE JOURNAL OF APPLIED PHYSICS. 55(9):93004 (2016)journal articl

Changes in parotid gland morphology and function in patients treated with intensity-modulated radiotherapy for nasopharyngeal and oropharyngeal tumors

OBJECTIVE: To evaluate the morphological changes of the parotid glands in patients treated with intensity-modulated radiotherapy (IMRT) for nasopharyngeal and oropharyngeal tumors and the correlations with parotid function. METHODS: Ten patients with nasopharyngeal and oropharyngeal tumors treated with IMRT between May 2009 and January 2010 at Hokkaido University Hospital were included in this study. In the morphological assessment of the parotid glands, the sizes and computed tomography (CT) numbers of the bilateral parotid glands before and after IMRT with CT were calculated. For functional assessment of the parotid glands, we conducted the Saxon test and used a visual analog scale (VAS) for xerostomia evaluation. RESULTS: Reductions in saliva secretion were observed in the patients treated with IMRT for nasopharyngeal and oropharyngeal tumors, and there was a significant correlation between the reduction in saliva secretion and the VAS. The reductions in the parotid gland size and CT number were larger on the ipsilateral side than on the contralateral side. The reduction in saliva secretion was not significantly correlated with the reduction in parotid gland size, but was significantly correlated with the reduction in CT number. CONCLUSIONS: Morphological and functional changes of the parotid glands were observed after IMRT for nasopharyngeal and oropharyngeal tumors, and preservation of the contralateral parotid glands was only partly achieved. Among the morphological changes of the parotid glands, the CT number may be considered a predictor of parotid function after radiotherapy

Cesium Implant for Tongue Carcinoma with a Thickness of 1.5 cm or More: Cases Successfully Treated with a Modified Manchester System

∙The authors have no financial conflicts of interest. Purpose: Deciding on treatment carcinoma of the tongue when the tumor has a thickness of 1.5 cm or more is difficult. Surgery often requires wide resection and re-construction, leading to considerable functional impairment. A cesium implant is an attractive option, but according to the Manchester System, a two plane implant is needed. Materials and Methods: According to the textbook, a tumor is sandwiched between the needles, which are implanted at the edge of the tumor. This may cause an unnecessarily high dose to the outer surface of the tongue, which sometimes leads to a persistent ulcer. To avoid this complication, we invented a modified implantation method, and applied the method to five consecutive patients. Results: With a minimum follow-up of 2 years, all primary tumors in 5 consecutive patients have been controlled. No complications occurred in soft tissu

A comparison of diagnostic tools for Sjögren syndrome, with emphasis on sialography, histopathology, and ultrasonography

Objective. The present study examined the reliability and correlation of sialography, salivary gland biopsy, and ultrasonography for Sjögren's syndrome (SS), and evaluated the usefulness of ultrasonography as a diagnostic tool for SS in comparison with sialography and histopathology. Methods. Seventy-three patients who underwent sialography, ultrasonography, and salivary gland biopsy were included in this study. The study evaluated the diagnostic reliability and correlation of each kind of examination with SS. Results. There was a statistically significant difference in the sensitivities of sialography and histopathology, in the specificities of sialography and ultrasonography, and in the accuracies of sialography and both of ultrasonography and histopathology. The correlation coefficient (r) between sialography and ultrasonography was significantly higher than the others and indicated a good correlation. Conclusions. Ultrasonography can be used as a diagnostic tool for SS with its advantage of non-invasiveness and facility

Crosstalk of the Androgen Receptor with Transcriptional Collaborators: Potential Therapeutic Targets for Castration-Resistant Prostate Cancer

Prostate cancer is the second leading cause of death from cancer among males in Western countries. It is also the most commonly diagnosed male cancer in Japan. The progression of prostate cancer is mainly influenced by androgens and the androgen receptor (AR). Androgen deprivation therapy is an established therapy for advanced prostate cancer; however, prostate cancers frequently develop resistance to low testosterone levels and progress to the fatal stage called castration-resistant prostate cancer (CRPC). Surprisingly, AR and the AR signaling pathway are still activated in most CRPC cases. To overcome this problem, abiraterone acetate and enzalutamide were introduced for the treatment of CRPC. Despite the impact of these drugs on prolonged survival, CRPC acquires further resistance to keep the AR pathway activated. Functional molecular studies have shown that some of the AR collaborative transcription factors (TFs), including octamer transcription factor (OCT1), GATA binding protein 2 (GATA2) and forkhead box A1 (FOXA1), still stimulate AR activity in the castration-resistant state. Therefore, elucidating the crosstalk between the AR and collaborative TFs on the AR pathway is critical for developing new strategies for the treatment of CRPC. Recently, many compounds targeting this pathway have been developed for treating CRPC. In this review, we summarize the AR signaling pathway in terms of AR collaborators and focus on pyrrole-imidazole (PI) polyamide as a candidate compound for the treatment of prostate cancer

Recent Discoveries in the Androgen Receptor Pathway in Castration-Resistant Prostate Cancer

The androgen receptor (AR) is the main therapeutic target in advanced prostate cancer, because it regulates the growth and progression of prostate cancer cells. Patients may undergo multiple lines of AR-directed treatments, including androgen-deprivation therapy, AR signaling inhibitors (abiraterone acetate, enzalutamide, apalutamide, or darolutamide), or combinations of these therapies. Yet, tumors inevitably develop resistance to the successive lines of treatment. The diverse mechanisms of resistance include reactivation of the AR and dysregulation of AR cofactors and collaborative transcription factors (TFs). Further elucidating the nexus between the AR and collaborative TFs may reveal new strategies targeting the AR directly or indirectly, such as targeting BET proteins or OCT1. However, appropriate preclinical models will be required to test the efficacy of these approaches. Fortunately, an increasing variety of patient-derived models, such as xenografts and organoids, are being developed for discovery-based research and preclinical drug screening. Here we review the mechanisms of drug resistance in the AR signaling pathway, the intersection with collaborative TFs, and the use of patient-derived models for novel drug discovery

Clinical Significance of Amyloid Precursor Protein in Patients with Testicular Germ Cell Tumor

Introduction. The biological role of amyloid precursor protein (APP) is not well understood, especially in testicular germ cell tumors (TGCTs). Therefore, we aimed to investigate the immunoreactivity (IR) and expression of APP in TGCTs and evaluated its clinical relevance. Materials and Methods. We performed an analysis of immunohistochemistry and mRNA expression of APP in 64 testicular specimens and 21 snap-frozen samples obtained from 1985 to 2004. We then evaluated the association between APP expression and clinicopathological status in TGCTs. Results. Positive APP IR was observed in 9.8% (4/41) of seminomatous germ cell tumors (SGCTs) and 39.1% (9/23) of nonseminomatous germ cell tumors (NGCTs). NGCTs showed significantly more cases of positive IR (P=0.00870) and a higher mRNA expression level compared with those of SGCTs (P=0.0140). Positive APP IR was also significantly associated with α-fetoprotein (αFP) elevation (P=0.00870) and venous invasion (P=0.0414). Conclusion. We observed an elevated APP expression in TGCTs, especially in NGCTs. APP may be associated with a more aggressive cancer in TGCTs