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Abstract: The As-doped (Zn0.93Mn0.07)O layer, formed by As+ ion implantation and subsequent annealing at 900°C for 30s, showed a clear peak from (Ao,X) emission. The sample exhibited the positive charge polarity indicative of p-type conductivity in the rectification measurement. The hole concentration and the hole mobility were determined to be 2.6×1018 cm−3 and of 13.1cm2 V−1 s−1, from Hall effect measurements, respectively. The sample showing the stable p-type conductivity revealed high-T C ferromagnetism persisting up to ∼320K. At 300K, the periodic magnetic domain was clearly observed along the in-plane direction but not dependent on the surface morphology. The observed room temperature ferromagnetism is expected to originate from the increase of hole-mediated exchange interactions. [Copyright &y& Elsevier]

Portulaca oleracea is as a medicinal plant known for its neuroprotective, hepatoprotective, antidiabetic, antioxidant, anticancer, antimicrobial, antiulcerogenic, and anti-inflammatory activities. However, the specific active compounds responsible for the individual pharmacological effects of P. oleracea extract (95% EtOH) remain unknown. Here, we hypothesized that alkaloids, the most abundant constituents in P. oleracea extract, are responsible for its anti-inflammatory activity. We investigated the phytochemical substituents (compounds 1–22) using nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) and screened their effects on NO production in lipopolysaccharide (LPS)-induced macrophages. Compound 20, 1-carbomethoxy-β-carboline, as an alkaloid structure, ameliorated nitric oxide (NO) production, inducible nitric oxide synthase (iNOS), and proinflammatory cytokines associated with the mitogen-activated protein kinase (MAPK) pathways, p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Subsequently, we observed that compound 20 suppressed nuclear translocation of nuclear factor κB (NF-κB) using immunocytochemistry. Moreover, we recently reported that compound 8, trans-N-feruloyl-3', 7'-dimethoxytyramine, was originally purified from P. oleracea extracts. Our results suggest that 1-carbomethoxy-β-carboline, the most effective anti-inflammatory agent among alkaloids in the 95% EtOH extract of P. oleracea, was suppressing the MAPK pathway and nuclear translocation of NF-κB. Therefore, P. oleracea extracts and specifically 1-carbomethoxy-β-carboline may be novel therapeutic candidates for the treatment of inflammatory diseases associated with the activation of MAPKs and NF-κB. [ABSTRACT FROM AUTHOR]

Alkaloids 1–10 were isolated from the aerial parts of Tetrastigma hemsleyanum (APTH) and obtained from species of the genus Tetrastigma for the first time. The chemical structures of the isolated compounds were identified by NMR, UV, and MS analyses. Their anti-inflammatory activities were investigated by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. Among all the isolates, compounds 6, 7 and 10 showed potent inhibitory activity against LPS-stimulated NO production in RAW264.7 cells (IC50: 31.9, 25.2 and 6.3 μM, respectively). Furthermore, APTH and S-(−)-trolline (10) inhibited induction of inflammatory cytokines or mediators such as interleukin-1β (IL-1β) and inducible nitric oxide synthase (iNOS) via suppression of nuclear factor κB (NF-κB) translocation into the nucleus. In addition, 10 suppressed extracellular signal-regulated protein kinase 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) phosphorylation in a dose-dependent manner. These results conclusively demonstrated that compound 10 displays anti-inflammatory activity via suppression of NF-κB activation and the ERK-MAPK signaling pathway in LPS-stimulated RAW264.7 cells. [ABSTRACT FROM AUTHOR]

An abstract of the study "Sesquiterpenoids From the Rhizomes of Curcuma Phaeocaulis and Their Inhibitory Effects on LPS-Induced TLR4 Activation" by S. W. Lee and colleagues is presented.

Semiconductor nanopyramids (NPs) provide advantages in the development of novel functional optoelectronic devices due to their unique size-dependent properties. Here we demonstrate a new method for the fabrication of selectively self-assembled single-crystalline GaN NPs on the m-plane of periodically strained GaN/InGaN multiquantum disks embedded in the middle of GaN nanorods. The GaN NPs, which have ∼100 nm diameters and heights, are observed by scanning electron microscopy and their crystalline structure is confirmed by high-resolution transmission electron microscopy. Experimental analysis directly reveals the strain distribution along the growth direction of the NPs. Cathodoluminescence measurements on a single NP show that its emission energy redshifts compared with that of bulk GaN, corroborating the results showing the formation of tensile strain in the NP. Observations of the uniform distribution and localization of these NPs show the possibility of further tuning their size and density by controlling periodically strained nanorod surfaces. [ABSTRACT FROM AUTHOR]

The article presents a correction to the article "Improved ferromagnetism of (Zn0.93Mn0.07)O through rapid thermal annealing," by Sejoon Lee, Yoon Shon, Seung-Woong Lee, Sun Jae Hwang, Hye Sung Lee, Tae Won Kang and Deuk Young Kimb published in an earlier issue of the journal.

Celastrus orbiculatus Thunb has been known as an ethnopharmacological medicinal plant for antitumor, anti-inflammatory, and analgesic effects. Although various pharmacological studies of C . orbiculatus extract has been reported, an anti-inflammatory mechanism study of their phytochemical constituents has not been fully elucidated. In this study, compounds 1 - 17 , including undescribed podocarpane-type trinorditerpenoid ( 3 ), were purified from C . orbiculatus and their chemical structure were determined by high-resolution electrospray ionization mass (HRESIMS) and nuclear magnetic resonance (NMR) spectroscopic data. To investigate the anti-inflammatory activity of compounds 1 - 17 , nitric oxide (NO) secretion was evaluated in LPS-treated murine macrophages, RAW264.7 cells. Among compounds 1 - 17 , deoxynimbidiol ( 1 ) and new trinorditerpenoid ( 3 ) showed the most potent inhibitory effects (IC 50 : 4.9 and 12.6  μ M, respectively) on lipopolysaccharide- (LPS-) stimulated NO releases as well as proinflammatory mediators, such as inducible nitric oxide (iNOS), cyclooxygenase- (COX-) 2, interleukin- (IL-) 1 β , IL-6, and tumor necrosis factor- (TNF-) α . Its inhibitory activity of proinflammatory mediators is contributed by suppressing the activation of nuclear transcription factor- (NF-) κ B and mitogen-activated protein kinase (MAPK) signaling cascades including p65, inhibition of NF- κ B (I κ B), extracellular signal-regulated kinase (ERK), c-Jun NH 2 -terminal kinase (JNK), and p38. Therefore, these results demonstrated that diterpenoids 1 and 3 obtained from C . orbiculatus may be considered a potential candidate for the treatment of inflammatory diseases., Competing Interests: The authors have declared that there is no conflict of interest., (Copyright © 2020 Hyun-Jae Jang et al.)

Three undescribed diarylheptanoids (3: -5: ) and six known curcuminoids (1, 2: , and 6: -9: ) were obtained from the ethyl acetate-soluble fraction of an ethanolic extract of Curcuma phaeocaulis . Their chemical structures and absolute configurations were elucidated by high-resolution electrospray ionization mass spectrometry, nuclear magnetic resonance spectroscopy, circular dichroism spectroscopy, and the modified Mosher's method. Previous studies constructed Hep3B cells stably transfected with pSTAT3-Luc plasmid containing STAT3 binding site to discover STAT3 inhibitors from natural products. The STAT3 inhibitory activities of all isolates were measured in transfected Hep3B cells after treatment with IL-6. Compound 5: ((5 R )-1,7-Bis(3,4-dimethoxyphenyl)-3-methoxy-1-hepten-5-ol), demethoxycurcumin (7: ), and curcumin (8: ) exhibited significant inhibitory activity (IC 50 values: 11.1, 1.9, and 1.6 µM, respectively). Furthermore, IL-6-induced phosphorylation of STAT3, and the mRNA expression levels of inflammation-related genes such as CRP, IL-1β, ICAM-1, and SOCS3 were significantly reduced by exposure to compound 5: . These data suggested that the inhibitory activity of 5: is associated with the suppression of STAT3 phosphorylation. Thus, compound 5: may be a promising candidate for the treatment of cancer or inflammatory diseases related to the IL-6/STAT3 signaling pathway., Competing Interests: The authors declare no conflicts of interest., (Georg Thieme Verlag KG Stuttgart · New York.)

The seeds of Alpinia katsumadai yielded two new acyclic triterpenoids, 2,3,6,22,23-pentahydroxy-2,6,11,15,19,23-hexamethyl-tetracosa-7,10,14,18-tetraene ( 3 ) and 2,3,6,22,23-pentahydroxy-2,10,15,19,23-hexamethyl-7-methylenetetracosa-10,14,18-triene ( 4 ), as well as two known compounds, 2,3,22,23-tertrahydroxy-2,6,10,15,19,23-hexamethyl-tetracosa-6,10,14,18-tetraene ( 1 ) and 2,3,5,22,23-pentahydroxy-2,6,10,15,19,23-hexamethyl-tetracosa-6,10,14,18-tetraene ( 2 ). The absolute configurations of 2 and 3 , which were determined by means of a modified Mosher's method, are suggested as ( 3 R ; 5 S ; 22 R ) and ( 3 R ; 22 R ), respectively. Compounds 1 - 4 inhibited IL-6-induced JAK2/STAT3 activity in a dose-dependent fashion, with IC 50 values of 0.67, 0.71, 2.18, and 2.99 μM. Moreover, IL-6-stimulated phosphorylation of STAT3 was significantly suppressed in U266 cells by the administration of A. katsumadai EtOH extract and Compounds 1 and 2 . These results suggest that major phytochemicals, Compounds 1 and 2 , obtained from A. katsumadai may be useful candidates for designing new IL-6 inhibitors as anti-inflammatory agents.

This study investigated the chemical composition changes of Salvia plebeia R.Br. cultivated under different light sources, including florescent light and sunlight. The plants were exposed to fluorescent light for four months and sunlight and then examined for the next 5-7 months. Plants were harvested monthly during the seven months, and we examined whether the difference in light source affected the phenolic and flavonoid contents and antioxidant activity. A simple and reliable HPLC method using a PAH C 18 column was applied for the quantitative analysis of two triterpenoids from the S. plebeia groups. Oleanolic acid (OA) and ursolic acid (UA) showed good linearity ( R ² > 0.9999) within the test ranges (0.005-0.05 mg/mL), and the average percentage recoveries of the OA and UA were 95.1-104.8% and 97.2-107.1%, respectively. The intra- and inter-day relative standard deviations (RSDs) were less than 2.0%. After exposure to sunlight, the phenolic contents, including rosmarinic acid, showed a reduced tendency, whereas the flavonoid contents, including homoplantaginin and luteolin 7-glucoside, were increased. The content of the triterpenoids also showed an increased tendency under sunlight irradiation, but the variance was not larger than those of the phenolic and flavonoid contents. Among experimental groups, the group harvested at six months, having been exposed to sunlight for two months, showed the most potent antioxidant activity. Therefore, these results showed that the chemical composition and antioxidant activities of S. plebeia R.Br. was affected from environmental culture conditions, such as light source. Our studies will be useful for the development of functional materials using S. plebeia R.Br., Competing Interests: The authors declare no conflicts of interest.

Two new feruloyl amides, N-cis-hibiscusamide (5) and (7'S)-N-cis-feruloylnormetanephrine (9), and eight known feruloyl amides were isolated from Portulaca oleracea L. and the geometric conversion of the ten isolated feruloyl amides by UV light was verified. The structures of the feruloyl amides were determined based on spectroscopic data and comparison with literature data. The NMR data revealed that the structures of the isolated compounds showed cis/trans-isomerization under normal laboratory light conditions. Therefore, cis and trans-isomers of feruloyl amides were evaluated for their convertibility and stability by UV light of a wavelength of 254 nm. After 96 h of UV light exposure, 23.2%-35.0% of the cis and trans-isomers were converted to trans-isomers. Long-term stability tests did not show any significant changes. Among all compounds and conversion mixtures collected, compound 6 exhibited the strongest inhibition of IL-6-induced STAT3 activation in Hep3B cells, with an IC50 value of 0.2 μM. This study is the first verification of the conversion rates and an equilibrium ratio of feruloyl amides. These results indicate that this natural material might provide useful information for the treatment of various diseases involving IL-6 and STAT3.

Endoplasmic reticulum (ER) stress is linked with development and maintenance of cancer, and serves as a therapeutic target for treatment of cancer. Verrucarin A, isolated from the broth of Fusarium sp. F060190, showed potential inhibitory activity on tunicamycin-induced ER stress in FaO rat liver cells. In addition, the compound decreased tunicamycin-induced GRP78 promoter activity in a dose dependent manner without inducing significant inhibition of luciferase activity and cell growth for 6 and 12 h. Moreover, the compound decreased the expression of GRP78, CHOP, XBP-1, and suppressed XBP-1, and reduced phosphorylation of IRE1α in FaO rat liver cells. This evidence suggests for the first time that verrucarin A inhibited tunicamycin-induced ER stress in FaO rat liver cells.

Three saikosaponins were isolated from the MeOH extract of the roots of Bupleurum falcatum L.: saikosaponins B3 (1); B4 (2); and D (3). Of the three, compound 3 inhibited the interaction of selectins (E, L, and P) and THP-1 cells with IC50 values of 1.8, 3.0 and 4.3 µM, respectively. Also, the aglycone structure 4 of compound 3 showed moderate inhibitory activity on L-selectin-mediated cell adhesion. From these results, we suspect that compound 3 isolated from Bupleurum falcatum roots would be a good candidate for therapeutic strategies to treat inflammation.

A reproducible analytical method using reverse-phase high liquid performance chromatography combined with UV detecting was developed for the quantitative determination of four compounds isolated from the ethanol extract of Phaseolus angularis seeds (PASE): oleanolic acid (1), oleanolic acid acetate (2), stigmasterol (3) and β-sitosterol (4). This method was fully validated in terms of linearity (r2 > 0.999), accuracy (98.5%-100.8%), precision (<0.92%), LOD (<0.0035 mg/mL), and LOQ (<0.0115 mg/mL). The effects of the PASE and isolated compounds 1-4 on TLR4 activation were tested in THP1-Blue cells. Among the tested substances, compound 2 showed potent inhibitory activity with an IC50 value of 3.89 ± 0.17 µM.

Inhibiting interleukin-6 (IL-6) has been postulated as an effective therapy in the pathogenesis of several inflammatory diseases. In this study, seven flavonoids were isolated from the methanol extracts of Psoralea corylifolia by bioactivity-guided fractionation. The structures of bakuchiol (1), bavachinin (2), neobavaisoflavone (3), corylifol A (4), corylin (5), isobavachalcon (6), and bavachin (7) were determined by spectroscopic analysis (1H-, 13C- NMR and MS). We demonstrated that compounds 1-7 showed an inhibitory effect on IL-6-induced STAT3 promoter activity in Hep3B cells with IC50 values of 4.57 ± 0.45, 3.02 ± 0.53, 2.77 ± 0.02, 0.81 ± 0.15, 1.37 ± 0.45, 2.45 ± 0.13, and 4.89 ± 0.05 µΜ, respectively. These compounds also inhibited STAT3 phosphorylation induced by IL-6 in Hep3B cells. Overall, several flavonoids from P. corylifolia might be useful remedies for treating inflammatory diseases by inhibiting IL-6-induced STAT3 activation and phosphorylation., (Georg Thieme Verlag KG Stuttgart · New York.)

Phenylpyropenes A, B, and C, isolated from Penicillium griseofulvum F1959, inhibited DGAT in rat liver microsomes with IC50 values of 78.7+/-1.6, 21.7+/-0.2, and 11.04+/-0.2 mM, respectively. In addition, a kinetic analysis using a Lineweaver-Burk plot revealed that phenylpyropene C was a noncompetitive inhibitor of DGAT. The apparent Michaelis constant (Km) value and inhibition constant (Ki) value were calculated to be 8 mM and 10.4 mM, respectively. Moreover, phenylpyropene C inhibited triglyceride formation in HepG2 cells.

Acyl-coenzyme A: cholesterol acyltransferase (ACAT) catalyzes cholesterol esterification and plays an important role in the intestinal absorption of cholesterol, hepatic production of lipoproteins, and accumulation of cholesteryl ester within cells. During the course of screening to find ACAT inhibitors from microbial sources, the present authors isolated pyripyropene A from Penicillium griseofulvum F1959. Pyripyropene A, an ACAT2-specific inhibitor, has already been produced from Aspergillus fumigatus. Yet, Aspergillus fumigatus is a pathogen and only produces a limited amount of pyripyropene A, making the isolation of pyripyropene A troublesome. In contrast, Penicillium griseofulvum F1959 was found to produce approximately 28 times more pyripyropene A than Aspergillus fumigatus, plus this report also describes the ideal conditions for the production of pyripyropene A by Penicillium griseofulvum F1959 and its subsequent purification.