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Myrcauones A–D (1–4), four new phloroglucinol–terpene adducts were isolated from the leaves of Myrciaria cauliflora. Their structures with absolute configurations were elucidated by combination of spectroscopic analysis, single crystal X-ray diffraction, and electronic circular dichroism (ECD) calculations. Compound 1 was a rearranged isobutylphloroglucinol–pinene adduct featuring an unusual 2,3,4,4a,10,11-hexahydro-1H-3,11a-methanodibenzo[b,f]oxepin backbone. Compound 4 showed moderate antibacterial activity against Gram-positive bacteria including multiresistant strains. [ABSTRACT FROM AUTHOR]

This study focused on the role of methionine (MET) in the autophagy of gastric cancer stem cells (GCSCs) and aims to elaborate its regulatory mechanism. In the present study, the GCSCs were isolated from human gastric cancer cell lines using an anti-CD44 antibody, and then cultured in MET+ homocysteine (HCY)− or MET−HCY+ medium. In MET+HCY–treated GCSCs, autophagy was suppressed, the methylation and phosphorylation of RAB37 were elevated, and miR-200b expression was down-regulated. Lentiviral vector (LV-) carrying methionine-γ lyase (an enzyme that could specifically lyse MET; Metase) promoted autophagy, reduced the methylation and phosphorylation of RAB37, and up-regulated miR-200b expression in MET+HCY–-treated GCSCs. Then, we found that miR-200b suppressed the expression of protein kinase C α (PKCα), a protein that could inactivate RAB37 through promoting its phosphorylation. LV-Metase down-regulated RAB37 phosphorylation via miR-200b/PKCα, thus promoting the RAB37-mediated autophagy and suppressing cell viability in MET+HCY–treated GCSCs. Finally, the in vivo study proved that LV-Metase treatment inhibited tumor growth through up-regulating RAB37 expression. In conclusion, MET suppressed RAB37 expression via enhancing its methylation and suppressed RAB37 activity via miR-200b/PKCα axis, thus repressing RAB37-mediated autophagy in GCSCs. The supplementation of Metase lysed MET, thus inducing the autophagy of GCSCs and inhibiting tumor growth. [ABSTRACT FROM AUTHOR]

The intraoperatively rotational control of femoral shaft fractures treated with a closed intramedullary interlocking nailing is a challenging problem. A novel surgical technique that includes respective insertions of guidewires into the proximal and distal femur under the guidance of a 2-dimensional fluoroscopy-based navigation system and the measurements of the intersection angle subtended by the proximal and distal guidewires with the smartphone positional software has been designed to provide intraoperatively quantitative parameters of femoral rotation deformation. The comparison of these parameters with preoperative measurement values of the contralateral intact femur on computed tomography images was used to align the proximal and distal femur fragments based on periaxial rotation. The purpose of this study was to evaluate its clinical suitability. Ten adult patients with femoral shaft fractures were attempted to correct intraoperatively femoral rotational deformity using this novel technique. The additional operation time was 20.04 ± 3.27 minutes. The angle of femoral anteversion was 20.85° ± 4.22°, 38.14° ± 19.07°, and 22.77° ± 3.38° in the contralateral intact and preoperatively and postoperatively injured femur, respectively. The mean absolute difference between both limbs was preoperatively 21.55° ± 10.14° with a statistically significant difference ( P = .005) and postoperatively 3.24° ± 1.69° with no statistically significant difference ( P = .092). Our results showed this novel technique could become an effective tool to correct intraoperatively rotational malalignment of femoral fractures. [ABSTRACT FROM AUTHOR]

PEGylated and folate-targeted chitosan polymeric nanoparticles (FPNs) for the treatment of gastric carcinoma were prepared successfully. OQC-anchored folate conjugates were synthesized and used in assembling FPNs nano-system for enhancing intracellular uptake against folate receptor overexpressing cancer cells. The results indicated that folate-targeted chitosan polymeric nanoparticles (CPNs) can reverse drug-resistant SGC-7901 cells of 5-fluorouracil (5-FU) compared with non-targeted CPNs. Increased therapeutic efficiency of 5-FU/METHFR shRNA co-loaded PNs were also tested in SGC-7901 cells and compaed with 5-FU or METHFR shRNA in solution, which was associated with increased cell inhibition function for single drug group and synergistic effects of 5-FU and METHFR shRNA at 2.0 µg/mL FPNs concentration. In addition, the cell accumulation levels of 5-FU in SGC-7901 cells was time dependent for these nanoparticles. FPNs (effective diameter: 83.2 ± 1.1 nm; polydispersity index: 0.193) could significantly boost cellular accumulation of 5-FU and overcome the drug efflux mechanism of MDR than 5-FU-loaded NPNs and 5-FU in solution. In conclusion, ligand-targeted PNs can be used as a potentially effective drug delivery system. [ABSTRACT FROM AUTHOR]

Two new isoaurones derivatives were obtained from Callistephus chinensis flower. Their structures were elucidated on the basis of extensive spectroscopic analyses. Both of the new compounds were evaluated cytotoxic activity. Phytochemical investigation of Callistephus chinensis flower led to the isolation of two new isoaurones derivatives (Z)-4′,4,10-trihydroxy-siamaurone (1) and (E)-4′,4,10-trihydroxy-siamaurone (2). The structures of these new compounds were identified by the interpretation of spectroscopic data (mainly 1D and 2D NMR) and by comparison with data reported in the literature. Both of the new compounds were evaluated for their cytotoxicity. [ABSTRACT FROM AUTHOR]

Two novel noroleanane saponins, tubeimoside A ( 1) and tubeimoside B ( 2), and a new dammarane triterpene saponin, tubeimoside C ( 3), together with two known compounds, 4 and 5, were isolated from the bulbs of Bolbostemma paniculatum ( Maxim.) Franquet. Compound 4 was found in this genus for the first time. Based on spectroscopic methods, including IR, NMR (DEPT, COSY, HMQC, HMBC, and TOCSY), and MS experiments, and chemical reactions, the structures of the new compounds were elucidated as 3 β-[ β- D-glucopyranosyl-(1→2)- β- D-glucopyranosyloxy]-2 β,23-dihydroxy-28-norolean-12-en-16-one ( 1), 3 β-[ β- D-glucopyranosyl-(1→2)- β- D-glucopyranosyloxy]-2 β,23-dihydroxy-28-norolean-12-en-22-one ( 2), (3 β,7 β)-7,18,20-trihydroxydammar-24-en-3-yl 2- O- α- L-arabinopyranosyl- β- D-glucopyranoside ( 3). [ABSTRACT FROM AUTHOR]

A new dammarane-type triterpene saponin was isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino. Its structural elucidation was accomplished mainly on the basis of the interpretation of spectroscopic data, such as IR, HR–TOF–MS and NMR. Its cytotoxic activity was evaluated against one human cancer cell line HL-60 using MTT assay. [ABSTRACT FROM PUBLISHER]

Four new dammarane-type triterpene saponins, 1-4, were isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino. Their structural elucidations were accomplished mainly on the basis of spectroscopic methods, such as IR, HR-TOF-MS, and NMR. Compounds 1-4 showed moderate cytotoxic activities against cancer cell lines HL-60, Colon205, and Du145 in vitro. [ABSTRACT FROM AUTHOR]

From the dried petals of Carthamus tinctorius, a new flavonoid, (2R)-4',5-dihydroxyl-6,7-di-O-β-d-glucopyranosyl flavanone (1) and a new aromatic glucoside, methyl-3-(4-O-β-d-glucopyranosylphenyl) propionate (4) were isolated along with four known compounds (2S)-4',5-dihydroxyl-6,7-di-O-β-d-glucopyranosyl flavanone (2), 6-hydroxykaempferol-3,6-di-O-β-d-glucopyranoside (3), 4-O-β-d-glucosyl-trans-p-coumaric acid (5), and 4-O-β-d-glucosyl-cis-p-coumaric acid (6). Their structures were identified on the basis of chemical and spectroscopic methods. [ABSTRACT FROM AUTHOR]

A new bufadienolide named 16β-acetoxy-bufarenogin (1), together with six known bufadienolides, namely, 11α,12β-dihydroxy-bufalin (2), bufotalin (3), hellebrigenin (4), desacetylbufotalin (5), gamabufotalin (6), and resibufagin (7) were isolated from Chan'Su. Of these, 2 was a new natural product. Their structures were elucidated by spectral methods. The cytotoxic activities in vitro of these compounds have been assayed against HeLa cell line. They all showed strong cytotoxic activities. [ABSTRACT FROM AUTHOR]

A new phenolic glycoside, sinapic acid 4-O-β-d-(6'-sinapoyl)glucopyranoside (1) and a new sucrose ester, 6,6'-di-O-sinapoylsurcose (3), were isolated from the roots of Cynanchum amplexicaule (Sieb. et Zucc.), along with two known compounds, 6-O-[E]-sinapoyl-d-glucopyranoside (2) and sibricose A1 (4). Their structures were elucidated on the basis of both chemical and spectroscopic methods. [ABSTRACT FROM AUTHOR]

In bone remodeling, osteogenesis is closely coupled to angiogenesis. Bone tissue engineering using multifunctional bioactive materials is a promising technique which has the ability to simultaneously stimulate osteogenesis and angiogenesis for repair of bone defects. We developed mesoporous bioactive glass (MBG)-doped poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) composite scaffolds as delivery vehicle. Two bioactive molecules, dimethyloxalylglycine (DMOG), a small-molecule angiogenic drug, and recombinant human bone morphogenetic protein-2 (rhBMP-2), an osteoinductive growth factor, were co-incorporated into the scaffold. The synergistic effects of DMOG and rhBMP-2 released in the composite scaffolds on osteogenic and angiogenic differentiation of hBMSCs were investigated using real-time quantitative polymerase chain reaction and western blotting. Moreover, in vivo studies were conducted to observe bone regeneration and vascular formation of critical-sized bone defects in rats using micro-computed tomography, histological analyses, Microfil® perfusion, fluorescence labeling, and immunohistochemical analysis. The results showed that DMOG and rhBMP-2 released in the MBG-PHBHHx scaffolds did exert synergistic effects on the osteogenic and angiogenic differentiation of hBMSCs. Moreover, DMOG and rhBMP-2 produced significant increases in newly-formed bone and neovascularization of calvarial bone defects in rats. It is concluded that the co-delivery strategy of both rhBMP-2 and DMOG can significantly improve the critical-sized bone regeneration. [ABSTRACT FROM AUTHOR]