ABSTRACT
The incidence of ovarian cancer has been epidemiologically related to female reproductive events and hormone replacement therapy after menopause. This highlights the importance of evaluating the role of sexual steroid hormones in ovarian cancer by the expression of enzymes related to steroid hormone biosynthesis in the tumor cells. This study was aimed to evaluate the presence of 17ß-hydroxysteroid dehydrogenase type 1 (17ß-HSD1), aromatase and estrogen receptor alpha (ERα) in the tumor cells and their association with the overall survival in 111 patients diagnosed with primary ovarian tumors. Positive immunoreactivity for 17ß-HSD1 was observed in 74% of the tumors. In the same samples, aromatase and ERα revealed 66% and 47% positivity, respectively. No association was observed of 17ß-HSD1 expression with the histological subtypes and clinical stages of the tumor. The overall survival of patients was improved in 17ß-HSD1-positive group in Kaplan-Meier analysis (P = 0.028), and 17ß-HSD1 expression had a protective effect from multivariate proportional regression evaluation (HR = 0.44; 95% CI 0.24-0.9; P = 0.040). The improved survival was observed in serous epithelial tumors but not in nonserous ovarian tumors. The expression of 17ß-HSD1 in the cells of the serous epithelial ovarian tumors was associated with an improved overall survival, whereas aromatase and ERα were not related to a better survival. The evaluation of hazard risk factors demonstrated that age and clinical stage showed worse prognosis, and 17ß-HSD1 expression displayed a protective effect with a better survival outcome in patients of epithelial ovarian tumors.
ABSTRACT
Hole spins in semiconductor quantum dots can be efficiently manipulated with radio-frequency electric fields owing to the strong spin-orbit interactions in the valence bands. Here we show that the motion of the dot in inhomogeneous strain fields gives rise to linear Rashba spin-orbit interactions (with spatially dependent spin-orbit lengths) and g-factor modulations that allow for fast Rabi oscillations. Such inhomogeneous strains build up spontaneously in the devices due to process and cool down stress. We discuss spin qubits in Ge/GeSi heterostructures as an illustration. We highlight that Rabi frequencies can be enhanced by 1 order of magnitude by shear strain gradients as small as 3×10^{-6} nm^{-1} within the dots. This underlines that spins in solids can be very sensitive to strains and opens the way for strain engineering in hole spin devices for quantum information and spintronics.
ABSTRACT
Harnessing the unique features of topological materials for the development of a new generation of topological based devices is a challenge of paramount importance. Using Floquet scattering theory combined with atomistic models we study the interplay among laser illumination, spin, and topology in a two-dimensional material with spin-orbit coupling. Starting from a topological phase, we show how laser illumination can selectively disrupt the topological edge states depending on their spin. This is manifested by the generation of pure spin photocurrents and spin-polarized charge photocurrents under linearly and circularly polarized laser illumination, respectively. Our results open a path for the generation and control of spin-polarized photocurrents.
ABSTRACT
The significance of the presence of androgen receptor (AR), estrogen receptor alpha (ER) and progesterone receptor (PR) in ovarian cancer patient survival has been a matter of numerous studies. This study was aimed to describe the expression profile of the three sexual steroid receptors in high-grade serous, endometrioid, mucinous and low-grade serous ovarian carcinoma and its association to the proliferation index in patients with primary ovarian carcinoma diagnosis, before any treatment. Eighty-one samples were obtained from the National Institute of Cancerology in Mexico City and were evaluated for the presence of AR, ER, PR and Ki67 by immunohistochemistry. The four subtypes of ovarian carcinoma displays a specific profile of the eight possible combinations of the steroid receptors with significant differences within the profile and the histological subtypes. High-grade serous carcinoma was characterized by a high frequency of both, triple-negative and AR+ ER- PR+ profiles. Endometrioid carcinoma presented a higher frequency of triple-positive profile. The presence of only AR+ profile was not observed in the endometrioid tumors. The relationship of the receptor profile with the proliferation index in the tumor epithelium shows that the expression of only ER is associated to a reduced proliferation index in endometrioid carcinoma. Steroid hormone receptor expression and co-expression could help characterize ovarian carcinoma.
ABSTRACT
The aim of this study was to examine the physical demands imposed on professional soccer players during 11-a-side friendly matches in relation to their playing position, using global positioning system (GPS) technology. One hundred and eleven match performances of a Spanish "La Liga" team during the 2010-11 and 2011-12 pre-seasons were selected for analysis. The activities of the players were monitored using GPS technology with a sampling frequency of 1 Hz. Total distance covered, distance in different speed categories, accelerations, and heart rate responses were analyzed in relation to five different playing positions: central defenders (n=23), full-backs (n=20), central midfielders (n=22), wide midfielders (n=26), and forwards (n=20). Distance covered during a match averaged 10.8 km, with wide and central midfielders covering the greatest total distance. Specifically, wide midfielders covered the greatest distances by very high-intensity running (>19.8 km·h-1) and central midfielders by jogging and running (7.2-19.7 km·h-1). On the other hand, central defenders covered the least total distance and at high intensity, although carried out more (p<0.05-0.01) accelerations than forwards, wide midfielders, and fullbacks. The work rate profile of the players obtained with the GPS was very similar to that obtained with semi-automatic image technologies. However, when comparing results from this study with data available in the literature, important differences were detected in the amount of distance covered by sprinting, which suggests that caution should be taken when comparing data obtained with the GPS with other motion analysis systems, especially regarding high-intensity activities.
