9 research outputs found
Pediatric vulvar squamous cell carcinoma in a liver transplantation recipient: a case report
Here we report the first Korean case of a girl who developed noninvasive squamous cell carcinoma of the vulva at the age of 16 years. She was taking tacrolimus, an immunosuppressive agent, after living-related liver transplantation. The vulvar masses were microscopically proved as vulvar intraepithelial neoplasm II and III, even squamous cell carcinoma in situ. Human papillomavirus subtypes (69 and 73) and human papillomavirus types (66, 70, 73, and 43) were detected in the vulvar mass and the cervicovaginal smear, respectively. The outcome of liver transplantation for children has been markedly improved during the last several decades. However, the present case highlights the need to perform periodic genital examinations for the adolescents after liver transplantation. In addition to the high risk and probable high subtypes, uncommonly found human papillomavirus subtypes were extracted from her vulvar cancer. The present case is the first to show the possible relationship between previously unknown and uncommon human papillomavirus subtypes and pediatric post-transplant vulvar squamous cell carcinoma. More attention should be paid to the vulvar and cervical surveillance of pediatric transplant recipients by both medical specialists and general physicians
Novel roles of luteinizing hormone (LH) in tissue regeneration-associated functions in endometrial stem cells
Abstract Luteinizing hormone (LH) stimulates the synthesis and secretion of the key steroid hormone estrogen, which subsequently promotes ovarian follicular growth and development. Therefore, the administration of exogenous LH to achieve superovulation (multiple ovulations) and an LH surge is commonly used as the most effective therapeutic option in a majority of in vitro fertilization (IVF) clinics. However, a relatively low pregnancy rate (between 20% and 35%) is one of the most challenging aspects of LH-based infertility treatment. Furthermore, the major cause of this low pregnancy rate in LH-based infertility treatment remains unidentified. Recent studies have shown that endometrial stem cell loss or deficiency can significantly decrease tissue regeneration ability during the menstrual cycle and reduce endometrial receptivity. In this context, we postulated that the low pregnancy rates following LH-based ovarian hyperactivation may be the result of the adverse effects of consecutive exogenous LH administration on endometrial stem cells. To the best of our knowledge, this study revealed for the first time that in addition to its previously reported roles in stimulating ovarian functions through the pituitary-gonadal axis, LH brings about the extragonadal suppression of various tissue regeneration-associated functions in endometrial stem cells, such as self-renewal, migration ability, multilineage differentiation potential, and pluripotency/stemness, by inhibiting pro-survival Akt and ERK1/2 signaling pathways in vitro and in vivo, and as a consequence, it decreases the endometrial receptivity
Attention-based reinforcement learning for real-time UAV semantic communication
Abstract
In this article, we study the problem of air-to-ground ultra-reliable and low-latency communication (URLLC) for a moving ground user. This is done by controlling multiple unmanned aerial vehicles (UAVs) in real time while avoiding inter-UAV collisions. To this end, we propose a novel multiagent deep reinforcement learning (MADRL) framework, coined a graph attention exchange network (GAXNet). In GAXNet, each UAV constructs an attention graph locally measuring the level of attention to its neighboring UAVs, while exchanging the attention weights with other UAVs so as to reduce the attention mismatch between them. Simulation results corroborates that GAXNet achieves up to 4.5x higher rewards during training. At execution, without incurring inter-UAV collisions, G2ANet improves reliability of air-to-ground network in terms of latency and error rate
SERPINB2 Is a Novel Indicator of Cancer Stem Cell Tumorigenicity in Multiple Cancer Types
Drug resistance is one of the major characteristics of cancer stem cells (CSCs) and a mechanism of tumor recurrence. Therefore, selectively targeting CSCs may be an effective therapeutic strategy to overcome cancer recurrence. In the present study, we found that exposure to tumorigenic compounds significantly increased the growth potential and stem-cell-like properties of various CSCs. Early-response genes involved in tumorigenesis can be used as specific markers to predict potential tumorigenicity. Importantly, for the first time we identified, a labile tumorigenic response gene—SERPINB2—and showed that tumorigenic compound exposure more profoundly affected its expression in CSCs than in non-stem cancer cells, although both cells exhibit basal expression of SERPINB2 in multiple cancer types. Our data also revealed a strong relationship between the significantly enhanced expression of SERPINB2 and metastatic progression in multiple cancer types. To the best of our knowledge, this is the first study to focus on the functions of SERPINB2 in the tumorigenicity of various CSCs and these findings will facilitate the development of promising tumorigenicity test platforms