Tokyo University of Science

About: Tokyo University of Science is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Catalysis & Thin film. The organization has 15800 authors who have published 24147 publications receiving 438081 citations. The organization is also known as: Tōkyō Rika Daigaku & Science University of Tokyo.

Nuclear β-catenin and CD44 upregulation characterize invasive cell populations in non-aggressive MCF-7 breast cancer cells

Abstract: Background In breast cancer cells, the metastatic cell state is strongly correlated to epithelial-to-mesenchymal transition (EMT) and the CD44+/CD24- stem cell phenotype. However, the MCF-7 cell line, which has a luminal epithelial-like phenotype and lacks a CD44+/CD24- subpopulation, has rare cell populations with higher Matrigel invasive ability. Thus, what are the potentially important differences between invasive and non-invasive breast cancer cells, and are the differences related to EMT or CD44/CD24 expression?

Change in the hormone receptor status following administration of neoadjuvant chemotherapy and its impact on the long-term outcome in patients with primary breast cancer.

Abstract: To evaluate the impact of change in the hormone receptor (HR) status (HR status conversion) on the long-term outcomes of breast cancer patients treated with neoadjuvant chemotherapy (NAC). We investigated 368 patients for the HR status of their lesions before and after NAC. On the basis of the HR status and the use/non-use of endocrine therapy (ET), the patients were categorised into four groups: Group A, 184 ET-administered patients with HR-positive both before and after NAC; Group B, 47 ET-administered patients with HR status conversion; Group C, 12 ET-naive patients with HR status conversion; Group D, 125 patients with HR-negative both before and after NAC. Disease-free survival in Group B was similar to that in Group A (hazard ratio, 1.16; P=0.652), but that in Group C was significantly lesser than that in Group A (hazard ratio, 6.88; P<0.001). A similar pattern of results was obtained for overall survival. Our results indicate that the HR status of tumours is a predictive factor for disease-free and overall survival and that ET appears to be suitable for patients with HR status conversion. Therefore, both the CNB and surgical specimens should be monitored for HR status.

Enhanced User Fairness Using Non-Orthogonal Access with SIC in Cellular Uplink

Abstract: This paper investigates the enhancement of cell-edge user throughput by using non-orthogonal access with a successive interference canceller (SIC) in the cellular uplink compared to orthogonal access, which is widely used in 3.9 and 4G mobile communication systems. Since both the total user throughput and cell-edge user throughput are important in a real system, we compare the cell-edge user throughput, while subject to the same total user throughput. The optimum resource allocation such as bandwidth and transmission power for each user is assumed for the respective access schemes based on the instantaneous channel conditions. Based on the evaluation results, we show that non-orthogonal access with a SIC can significantly enhance the cell-edge user throughput (thus user fairness) compared to the orthogonal access while achieving the same total user throughput in the context of the cellular uplink, which can yield some insights regarding the direction of the wireless access scheme for the systems beyond IMT-Advanced.

Life-span of solutions to semilinear wave equation with time-dependent critical damping for specially localized initial data

Abstract: This paper is concerned with the blowup phenomena for initial value problem of semilinear wave equation with critical time-dependent damping term DW $$\begin{aligned} {\left\{ \begin{array}{ll} \partial _t^2 u(x,t) -\Delta u(x,t) + \dfrac{\mu }{1+t}\partial _t u(x,t)=|u(x,t)|^p, &{} (x,t)\in \mathbb {R}^N \times (0,T),\\ u(x,0)=\varepsilon f(x),&{} x\in \mathbb {R}^N,\\ \partial _t u(x,0)=\varepsilon g(x),&{} x\in \mathbb {R}^N, \end{array}\right. } \end{aligned}$$ where $$N\in \mathbb {N},$$ $$\mu \in [0,\frac{N^2+N+2}{N+2})$$ and $$\varepsilon >0$$ is a parameter describing the smallness of initial data. Given data f, g are compactly supported in a small area inside of the unit ball. The result is the upper bound of lifespan of solution u with respects to the small parameter $$\varepsilon $$ when $$p_F(N)\le p\le p_0(N+\mu ),$$ where $$p_F(N)$$ denotes the Fujita exponent for the nonlinear heat equations and $$p_0(n)$$ denotes the Strauss exponent for nonlinear wave equation (DW) in n-dimension with $$\mu =0.$$ Consequently, by connecting the result of D’Abbicco–Lucente–Reissig (J Differ Equ 259:5040–5073, 2015), our result clarifies the threshold exponent $$p_0(N+\mu )$$ for dividing blowup phenomena and global existence of small solutions when $$N=3.$$ The crucial idea is to construct suitable test functions satisfying the conjugate linear equation $$\partial _t^2\Phi -\Delta \Phi -\partial _t(\frac{\mu }{1+t}\Phi )=0$$ of (DW) including the Gauss hypergeometric functions; note that the construction of test functions is different from Zhou–Han (Commun Partial Differ Equ 39:439–451, 2014).