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Extracellular vesicles from senescent hepatic stellate cells promote cell viability of hepatoma cells through increasing EGF secretion from differentiated THP‑1 cells
Since the discovery of the senescence-associated secretory phenotype, the role of senescent hepatic stellate cells (HSCs) in hepatocellular carcinoma (HCC) development has gained increasing attention. Similar to cytokines, extracellular vesicles (EVs) are essential for intercellular communication. However, the function of EVs derived from senescent HSCs in HCC progression has not been extensively studied. The aims of the present study were to characterize the EVs derived from senescent HSCs and determine their role in the tumor microenvironment. Cellular senescence was induced in human hepatic stellate cells (HHSteCs) with various concentrations of etoposide. Induction was confirmed using EdU staining and 53BP1 and p21 immunostaining. EVs were isolated by ultracentrifugation and analyzed by nanoparticle tracking analysis. Multiplex immunoassays were used to compare the levels of growth factors secreted from hepatoma cell lines and macrophage cells pretreated with EVs derived from senescent HHSteCs (senescent EVs) with those pretreated with EVs derived from normal cultured HHSteCs (normal EVs). Treatment with 25 µM etoposide for 3 days was the most effective at inducing senescence in HHSteCs. This finding was confirmed by induction of irreversible cell-cycle arrest, upregulation of 53BP1 and p21 expression, and increased SA-β-gal staining. Senescent HHSteCs released increased quantities of EV particles compared with normally cultured HHSteCs. Multiplex analysis revealed that there was no difference between hepatoma cell lines treated with normal EVs and those treated with senescent EVs in growth factor secretion. In contrast, the secretion of epidermal growth factor (EGF) was increased by macrophage cells treated with senescent EVs compared with those treated with normal EVs. Furthermore, senescent EVs did not affect the viability of hepatoma cells but increased the viability of hepatoma cells co-cultured with macrophage cells. In conclusion, the release of EVs from senescent HSCs was higher compared with normal HSCs. Furthermore, senescent EVs promoted HCC development by upregulating EGF secretion from macrophages
Perceived eHealth Literacy and Learning Experiences Among Japanese Undergraduate Nursing Students
This study aimed to describe undergraduate nursing students' perceived eHealth literacy and learning experiences of eHealth literacy in Japan and to clarify the relationship between these factors. We conducted a self-administered online questionnaire survey using a convenience sample of 353 Japanese undergraduate nursing students selected from three universities. Participants completed the eHealth Literacy Scale and questionnaires on learning experiences of eHealth literacy and some demographic factors. Participants had moderate perceived eHealth (mean [SD], 24.52 [5.20]). More than half the participants responded that they had no learning experiences of health or science literacy. We observed a positive correlation between the total mean eHealth literacy and learning experiences scores. Undergraduate nursing students in Japan had slightly lower perceived eHealth literacy than nursing students in other countries, hospital nurses, and even patients. Of the 353 participants in this study, 69.4% did not know “where to find helpful health resources on the Internet,” 80.2% of those lacked the skills “to evaluate health resources,” and 68.9% could not “differentiate the quality of health resources on the Internet”; few of the participants perceived themselves as having any experience in learning the six domains of eHealth literacy. Very few reported learning about health (43.3%) and scientific (21.8%) literacy. The low perceived eHealth literacy among participants might reflect lack of knowledge and confidence in eHealth literacy as well as their own low level of health-promoting behaviors; this might influence the quality of health education of clients and their families. Nursing educators should address the lack of eHealth literacy among undergraduate nursing students
Establishment of Novel High-Standard Chemiluminescent Assay for NTPase in Two Protozoans and Its High-Throughput Screening
Toxoplasma gondii is a major protozoan parasite and infects human and many other warm-blooded animals. The infection leads to Toxoplasmosis, a serious issue in AIDS patients, organ transplant recipients and pregnant women. Neospora caninum, another type of protozoa, is closely related to Toxoplasma gondii. Infections of the protozoa in animals also causes serious diseases such as Encephalomyelitis and Myositis-Polyradiculitis in dogs or abortion in cows. Both Toxoplasma gondii and Neospora caninum have similar nucleoside triphosphate hydrolases (NTPase), NcNTPase and TgNTPase-I in Neospora caninum and Toxoplasma gondii, respectively. These possibly play important roles in propagation and survival. Thus, we targeted the enzymes for drug discovery and tried to establish a novel high-standard assay by a combination of original biochemical enzyme assay and fluorescent assay to determine ADP content. We then validated whether or not it can be applied to high-throughput screening (HTS). Then, it fulfilled criterion to carry out HTS in both of the enzymes. In order to identify small molecules having inhibitory effects on the protozoan enzyme, we also performed HTS using two synthetic compound libraries and an extract library derived from marine bacteria and then, identified 19 compounds and 6 extracts. Nagasaki University collected many extracts from over 18,000 marine bacteria found in local Omura bay, and continues to compile an extensive collection of synthetic compounds from numerous drug libraries established by Japanese chemists
Development of an active fire monitoring algorithm for the GCOM-C observation
長崎大学学位論文 [学位記番号]博(水・環)乙第9号 [学位授与年月日]令和2年8月26
自動間欠的投与法を用いた胸部傍脊椎ブロックによる感覚遮断範囲の経時的変化に関する研究:ランダム化二重盲検群間試験
長崎大学学位論文 [学位記番号]博(医歯薬)乙第58号 [学位授与年月日]令和2年9月2
Evidence of sperm removal behaviour in an externally fertilizing species and compensatory behaviour for the risk of self-sperm removal
The removal of rival sperm from a female's sperm storage organ acts as a strong sperm competition avoidance mechanism, which has been reported only in internally fertilizing species and not at all in externally fertilizing species. This study demonstrated for the first time that nest-holding males of Bathygobius fuscus, an externally fertilizing marine fish, remove the sperm of rival sneaker males from the spawning nest by exhibiting tail-fanning behaviour within the nest. Males showed tail-fanning behaviour when semen was artificially
injected into the nest but not when seawater was injected, and in open nests this behaviour resulted in higher paternity rates for the focal male. The sperm removal behaviour entails the risk of removing their own sperm; therefore, additional sperm release behaviour is likely necessary to benefit from the sperm removal effect. Consistent with this, males increased post-fanning sperm release behaviour more
in the semen than in the seawater injection treatment. Moreover, males who had removed sperm for a longer time spent more time releasing sperm after the removal, suggesting that the additional sperm release behaviour compensated for the loss of their own sperm. These results suggest that sperm removal behaviour is not restricted to internally fertilizing organisms and deserves further investigation in this and other species