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991.
Hyun Ji Kim Hye Ja Lee Mi Kyung Park Kyung Jin Gang Hyun Jung Byun Jeong Ho Park Mi Kyung Kim Soo Youl Kim Chang Hoon Lee 《Biomolecules & therapeutics.》2014,22(3):207-212
Skin hyperpigmentation is one of the most common skin disorders caused by abnormal melanogenesis. The mechanism and key factors at play are not fully understood. Previous reports have indicated that cystamine (CTM) inhibits melanin synthesis, though its molecular mechanism in melanogenesis remains unclear. In the present study, we investigated the effect of CTM on melanin production using ELISA reader and the expression of proteins involved in melanogenesis by Western blotting, and examined the involvement of transglutaminase-2 (Tgase-2) in SK-MEL-2 human melanoma cells by gene silencing. In the results, CTM dose-dependently suppressed melanin production and dendrite extension in α-MSH-induced melanogenesis of SK-MEL-2 human melanoma cells. CTM also suppressed α-MSH-induced chemotactic migration as well as the expressions of melanogenesis factors TRP-1, TRP-2 and MITF in α-MSH-treated SK-MEL-2 cells. Meanwhile, gene silencing of Tgase-2 suppressed dendrite extension and the expressions of TRP-1 and TRP-2 in α-MSH-treated SK-MEL-2 cells. Overall, these findings suggested that CTM suppresses α-MSH-induced melanogenesis via Tgase-2 inhibition and that therefore, Tgase-2 might be a new target in hyperpigmentation disorder therapy. 相似文献
992.
993.
Chan-Woo Park Sung Wook Seo Noeul Kang BeomSeok Ko Byung Wook Choi Chang Min Park Dong Kyung Chang Hwiyoung Kim Hyunchul Kim Hyunna Lee Jinhee Jang Jong Chul Ye Jong Hong Jeon Joon Beom Seo Kwang Joon Kim Kyu-Hwan Jung Namkug Kim Seungwook Paek Soo-Yong Shin Soyoung Yoo Yoon Sup Choi Youngjun Kim Hyung-Jin Yoon 《Journal of Korean medical science》2020,35(48)
994.
Julieann C. Lee Javier E. Villanueva‐Meyer Sean P. Ferris Elaine M. Cham Jacob Zucker Tabitha Cooney Ahmed Gilani Bette K. Kleinschmidt‐DeMasters Dimitri Trembath Manuela Mafra Jason Chiang David W. Ellison Soo‐Jin Cho Andrew E. Horvai Jessica Van Ziffle Courtney Onodera Patrick Devine James P. Grenert Carmen M.A. de Voijs W.T. Marja van Blokland Wendy W.J. de Leng Marieke J. Ploegmakers Uta Flucke Melike Pekmezci Andrew W. Bollen Tarik Tihan Christian Koelsche Andreas von Deimling Pieter Wesseling David A. Solomon Arie Perry 《Brain pathology (Zurich, Switzerland)》2020,30(2):213-225
Desmoplastic small round cell tumors (DSRCTs) are highly aggressive sarcomas that most commonly occur intra‐abdominally, and are defined by EWSR1‐WT1 gene fusion. Intracranial DSRCTs are exceptionally rare with only seven previously reported fusion‐positive cases. Herein, we evaluate the clinical, morphologic, immunohistochemical and molecular features of five additional examples. All patients were male (age range 6–25 years; median 11 years), with four tumors located supratentorially and one within the posterior fossa. The histologic features were highly variable including small cell, embryonal, clear cell, rhabdoid, anaplastic and glioma‐like appearances. A prominent desmoplastic stroma was seen in only two cases. The mitotic index ranged from <1 to 12/10 HPF (median 5). While all tumors showed strong desmin positivity, epithelial markers such as EMA, CAM 5.2 and other keratins were strongly positive in only one, focally positive in two and negative in two cases. EWSR1‐WT1 gene fusion was present in all cases, with accompanying mutations in the TERT promoter or STAG2 gene in individual cases. Given the significant histologic diversity, in the absence of genetic evaluation these cases could easily be misinterpreted as other entities. Desmin immunostaining is a useful initial screening method for consideration of a DSRCT diagnosis, prompting confirmatory molecular testing. Demonstrating the presence of an EWSR1‐WT1 fusion provides a definitive diagnosis of DSRCT. Genome‐wide methylation profiles of intracranial DSRCTs matched those of extracranial DSRCTs. Thus, despite the occasionally unusual histologic features and immunoprofile, intracranial DSRCTs likely represent a similar, if not the same, entity as their soft tissue counterpart based on the shared fusion and methylation profiles. 相似文献
995.
996.
Soohyun Nam Genevieve F. Dunton Monica R. Ordway Garrett I. Ash Sangchoon Jeon David Vlahov Robin Whittemore LaRon E. Nelson Rajita Sinha Marcella Nunez-Smith Douglas A. Granger 《Research in nursing & health》2020,43(5):453-464
Perceived racial discrimination is linked to unhealthy behaviors and stress-related morbidities. A compelling body of research indicates that perceived racial discrimination may contribute to health disparities among African Americans (AAs). The purposes of this study were to describe the study protocol including data collection procedures and study measures and to evaluate the feasibility and acceptability of intensive biobehavioral data collection using ecological momentary assessment (EMA), salivary biomarkers, and accelerometers over 7 days among middle-aged AAs with a goal of understanding the relationships between perceived racial discrimination and biobehavioral responses to stress. Twelve AA men and women participated in the feasibility/acceptability study. They completed surveys, anthropometrics, and received in-person training in EMA and saliva sample collection at baseline. Participants were asked to respond to the random prompt text message-based EMA five times a day, wear an accelerometer daily for 7 days, and to self-collect saliva samples four times a day for 4 consecutive days. The EMA surveys included perceived racial discrimination, affective states, lifestyle behaviors, and social and physical contexts. The mean EMA response rate was 82.8%. All participants collected saliva samples four times a day for 4 consecutive days. About 83% of participants wore the accelerometer on the hip 6 out of 7 days. Despite the perception that the intensive nature of assessments would result in high participant burden, the acceptability of the study procedures was uniformly favorable. 相似文献
997.
Jin Yang Baek In Ho Park Jae-Hoon Song Kwan Soo Ko 《Journal of clinical microbiology》2014,52(6):2096-2099
The prevalence of serogroup 6 among 1,206 Streptococcus pneumoniae clinical isolates collected from Korean hospitals over three periods (1996 to 2001, 2004 to 2006, and 2008 to 2009) was investigated. The number of serogroup 6 isolates increased from 9.7 to 17.5% over the three periods. While the proportion of serotype 6A and 6D isolates increased significantly, that of serotype 6B isolates decreased. Twenty-four isolates (2.0%) were typed as the recently identified putative serotype 6E or genetic variants of serotype 6B. The results suggest that the lack of change in frequency of serotype 6B, in spite of the introduction of the PCV7 vaccine as seen in previous studies in South Korea, might be due mainly to the improper inclusion of putative serotype 6E in serotype 6B. All but three serotype 6E isolates belonged to CC90, indicating their clonal expansion. 相似文献
998.
999.
1000.
Jung Yum Eun Hye Park Keun Bon Ku Ji An Kim Seung Kyoo Oh Hyun Soo Kim Sang Heui Seo 《Archives of virology》2014,159(10):2745-2749
We studied the pathogenesis and transmissibility of a novel avian-origin H7N9 influenza virus in pigs. When pigs were infected with H7N9 influenza virus, they did not show any clear clinical signs (such as sneezing, fever and loss of body weight), and they shed viruses through their noses for 2 days after infection. No transmission occurred between infected and naïve pigs. Pigs suffered from mild pneumonia, which was accompanied by the induction of inflammatory cytokines and chemokines such as IL-8 and CCL1. Taken together, our results suggest that pigs may not play an active role in transmitting H7N9 influenza virus to mammals. 相似文献