The nuclear scaffold protein SAF-A is required for kinetochore-microtubule attachment and contributes to the targeting of Aurora-A to mitotic spindles

Ma N., Matsunaga S., Morimoto A., et al. The nuclear scaffold protein SAF-A is required for kinetochore-microtubule attachment and contributes to the targeting of Aurora-A to mitotic spindles. Journal of Cell Science, 124, 3, 394. https://doi.org/10.1242/jcs.063347

High-pressure xenon gas time projection chamber with scalable design and its performance at around the Q value of 136^{136}Xe double-beta decay

We have been developing a high-pressure xenon gas time projection chamber (TPC) to search for neutrinoless double beta ($0\nu\beta\beta$) decay of $^{136}$Xe. The unique feature of this TPC is in the detection part of ionization electrons, called ELCC. ELCC is composed of multiple units, and one unit covers 48.5 $\mathrm{cm}^2$. A 180 L size prototype detector with 12 units, 672 channels, of ELCC was constructed and operated with 7.6 bar natural xenon gas to evaluate the performance of the detector at around the Q value of $^{136}$Xe $0\nu\beta\beta$. The obtained FWHM energy resolution is (0.73 $\pm$ 0.11) % at 1836 keV. This corresponds to (0.60 $\pm$ 0.03) % to (0.70 $\pm$ 0.21) % of energy resolution at the Q value of $^{136}Xe$ $0\nu\beta\beta$. This result shows the scalability of the AXEL detector with ELCC while maintaining high energy resolution. Factors determining the energy resolution were quantitatively evaluated and the result indicates further improvement is feasible. Reconstructed track images show distinctive structures at the endpoint of electron tracks, which will be an important feature to distinguish $0\nu\beta\beta$ signals from gamma-ray backgrounds.Comment: 33 pages, 24 figures, preprint accepted by PTE

Pathological evaluation of the accuracy of a fluorescence spectroscopy system for detecting parathyroid glands

Purpose A fluorescence-based technique for the detection of parathyroid glands (PGs) intraoperatively was previously reported. The technique was based on the phenomenon in which PGs emit autofluorescence when exposed to near-infrared light and we undertook an evaluation to consider the pathological accuracy of the method. Methods The study comprised 17 patients (18 specimens) who underwent thyroid surgery at Kushiro City General Hospital between November 2018 and June 2019. We searched for PGs intraoperatively using a fluorescence spectroscopy system and evaluated the pathological accuracy of the system. We statistically evaluated the clinical factors associated with the accuracy of the system, including age, gender, body mass index, laterality, disease state, renal function, and comorbidity. Results Eighteen specimens were evaluated pathologically, with 13 specimens confirmed as PGs. These were evaluated as "true positive," giving a positive predictive value of 72.2% (13/18). Among the false-negative cases, one specimen was a metastatic lymph node in a patient with papillary thyroid carcinoma. There was a significant difference in the true-positive rates between malignant (25%) and benign (85.7%) disease (P = 0.044). Conclusion We consider that this technique is useful, however, we have to exercise care in malignant cases as the true-positive rate may be low

Residual tumour detection in post-treatment granulation tissue by using advanced diffusion models in head and neck squamous cell carcinoma patients

Purpose: To evaluate the detectability of the residual tumour in post-treatment granulation tissue using parameters obtained with an advanced diffusion model in patients with head and neck squamous cell carcinoma (HNSCC) treated by chemoradiation therapy. Materials and methods: We retrospectively evaluated 23 patients with HNSCC after the full course of chemoradiation therapy. The diffusion-weighted image (DWI) acquisition used single-shot spin-echo echo-planar imaging with 11 b-values (0-1000). We calculated 10 DWI parameters using a mono-exponential model, a bi-exponential model, a stretched exponential model (SEM), a diffusion kurtosis imaging (DKI) model and a statistical diffusion model (SDM) in the region of interest (ROI) placed on the post-treatment granulation tissue. The presence of residual tumour was determined by histological findings or clinical follow-up. Results: Among the 23 patients, seven patients were revealed to have residual tumour. The univariate analysis revealed significant differences in six parameters between the patients with and without residual tumour. From the receiver operating characteristic curve analysis, the highest area under curve was detected in the center of the Gaussian distribution of diffusion coefficient (Ds) obtained by the SDM. The multivariate analysis revealed that the Ds and diffusion heterogeneity (α) obtained by the SEM were predictors for the presence of residual tumour. Conclusion: DWI parameters obtained by advanced fitting models will be one of the diagnostic tools for the detection of residual tumour

Confirmation of the 8th edition of the AJCC/UICC TNM staging system for HPV-mediated oropharyngeal cancer in Japan

Background: Several studies have demonstrated that the 7th edition of the AJCC/UICC TNM staging classification system does not consistently distinguish between prognostic subgroups for human papillomavirus (HPV)-mediated oropharyngeal squamous cell carcinoma (OPSCC). The 8th edition of the AJCC/UICC TNM staging came into effect for use with HPV-mediated OPSCC on or after January 1, 2017. This study confirms that the 8th edition of the AJCC/UICC TNM staging system for HPV- mediated OPSCC accurately reflects disease outcomes. Patients and methods:We retrospectively analyzed 195 patients with OPSCC treated at Hokkaido University Hospital, Sapporo, Japan between 1998 and 2015. HPV status was evaluated by immunohistochemical analysis of p16. Results: Of the 195 OPSCC patients, 111 (56.9%) were p16 positive, and 84 (43.1%) were p16 negative. The 3-year overall survival rate (OS) was significantly lower in the p16-negative patients with stage III-IV in comparison with those with stage I-II (55.0% vs 93.1%, p<0.01). The 3-year OS did not differ significantly between stage I-II and stage III-IV in the p16-positive patients (86.7% vs 87.7%). According to the 8th edition of the AJCC/UICC TNM staging system, stage I-II and stage III could be differentiated on the basis of the 3-year OS in the p16-positive patients (90.9% vs 70.2%, p<0.01). Conclusions: The 7th edition of the AJCC/UICC TNM staging system is suitable for use with p16-negative patients; however, it does not effectively discriminate between p16-positive patients. Therefore, the 8th edition of the AJCC/UICC TNM staging system is more suitable for HPV-mediated OPSCC in Japan

Lymph node metastasis in the suprasternal space from thyroid papillary cancer

The suprasternal space is a narrow space between the superficial and deep layers of the investing layers of the deep cervical fascia above the manubrium of the sternum. The suprasternal space has been paid little attention as a space with the potential for lymph node metastasis from both thyroid cancer and head and neck cancer. We experienced 2 patients who were found to have a lymph node in the suprasternal space preoperatively. Both of them had well-differentiated thyroid papillary carcinomas and level III and IV lymph node metastases as well as metastasis in the suprasternal space. We have not previously dissected the suprasternal space prophylactically in other patients with thyroid papillary cancer, but no patient has developed metastasis in this space to date. The suprasternal space is not usually dissected in atients with thyroid cancer. However, suprasternal space metastasis has been reported to occur occasionally in patients with lymph node metastases in levels III and IV. We consider that dissection of the suprasternal space, which is not routinely performed, should be done when preoperative examination suggests lymph node metastasis in the suprasternal space as dissection of this space is less invasive, easy to achieve, and is not time consuming. Greater attention should be paid to the suprasternal space as an area with the otential for lymph node metastasis from thyroid cancer