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Hibiscus syriacus L. exhibited promising potential as a new source of food and colorants containing various anthocyanins. However, the function of anthocyanins from H. syriacus L. has not been investigated. In the current study, we evaluated whether anthocyanins from the H. syriacus L. varieties Pulsae and Paektanshim (PS and PTS) inhibit melanin biogenesis. B16F10 cells and zebrafish larvae were exposed to PS and PTS in the presence or absence of α-melanocyte-stimulating hormone (α-MSH), and melanin contents accompanied by its regulating genes and proteins were analyzed. PS and PTS moderately downregulated mushroom tyrosinase activity in vitro, but significantly decreased extracellular and intracellular melanin production in B16F10 cells, and inhibited α-MSH-induced expression of microphthalmia-associated transcription factor (MITF) and tyrosinase. PS and PTS also attenuated pigmentation in α-MSH-stimulated zebrafish larvae. Furthermore, PS and PTS activated the phosphorylation of extracellular signal-regulated kinase (ERK), whereas PD98059, a specific ERK inhibitor, completely reversed PS- and PTS-mediated anti-melanogenic activity in B16F10 cells and zebrafish larvae, which indicates that PS- and PTS-mediated anti-melanogenic activity is due to ERK activation. Moreover, chromatography data showed that PS and PTS possessed 17 identical anthocyanins as a negative regulator of ERK. These findings suggested that anthocyanins from PS and PTS inhibited melanogenesis in vitro and in vivo by activating the ERK signaling pathway.

Epitaxial MgB2 thick films are grown on Al2O3 substrates at 600 °C by using the hybrid physical (HP)CVD technique. In order to obtain a high magnesium vapor pressure around the substrates, we use a special susceptor having a susceptor cap and achieve a very high growth rate of 0.17 μm min–1. Hexagonal-shaped columnar structures are observed by cross-sectional and planar-view transmission electron microscope (TEM) images. For the 1.7 μm thick film, the Tc is observed to be 40.5 K with a Jc of 1.5 × 106 A cm–2 at 30 K. The vortex pinning mechanism by intercolumnar boundaries will be discussed.

The aim of this study was to evaluate the surgical outcomes of laparoscopic cholecystectomy (LC) in patients who were diagnosed with severe acute cholecystitis (SAC) and to clarify the useful treatment modalities of SAC. Of 112 patients who presented SAC, we selected 99 patients and divided them into 3 groups: 37 patients who underwent preoperative percutaneous transhepatic gallbladder drainage (PTGBD; group 1), 62 patients with SAC but not indicated for PTGBD (group 2), and 59 patients with acute and chronic cholecystitis (group 3). The conversion rate was 2.7% (1/37) in group 1, 6.5% (4/62) in group 2, and 1.7% (1/59) in group 3. In groups 1 and 2, the postoperative stay and operative time were longer than those in group 3 with significant difference, respectively (P < 0.05). In group 2, there was correlation not only between postoperative stay and age but also between postoperative stay and ASA class (P < 0.05). In group 2, there was no correlation between time to operation and operative time and also between time to operation and postoperative stay, however, there was surprisingly significant correlation between time to operation and conversion rate in SAC (P = 0.018). In conclusion, PTGBD should selectively be performed in patients with severe comorbidities rather than improving surgical outcomes of LC for severe acute cholecystitis. If patients are not indicated for PTGBD, an early laparoscopic cholecystectomy is recommended because it can decrease conversion rate, although it cannot decrease operative time and postoperative stay.