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Two novel acylated steroidal sapogenins, 3β-acetoxy-1α, 2α, 4β, 5α, 7α-pentahydroxy-spirost-25(27)-en-6-one (1) and (25S)-3α-acetoxy-1α, 2β, 4α, 5α, 7α-pentahydroxyspirostan-6-one (2), together with two known steroidal sapogenins (3 and 4), were isolated from Rohdea chinensis rhizomes. Their structures were elucidated by nuclear magnetic resonance (NMR) and mass spectrometry (MS) data. In addition, the antifungal activities of the isolated compounds against Penicillium digitatum and Rhizopus stolonifera were evaluated. Compound 2 significantly inhibited R. stolonifera growth, which was comparable to the positive control (sodium benzoate and carbendazim). Compound 4 showed the highest potency to inhibit P. digitatum growth compared to other compounds. [ABSTRACT FROM AUTHOR]

Twenty-one polycyclic polyprenylated acylphloroglucinols, including three new compounds named as hyperichoisins A (3), B (14) and C (21), were isolated from the aerial parts of Hypericum choisianum. The structures of those new compounds were elucidated by analysis of mass, NMR data, and chiroptical properties. A bioassay showed that otogirinin B had significant inhibitory effect on cell proliferation of A549. [ABSTRACT FROM AUTHOR]

A phytochemical investigation on the 75% EtOH extract of the aerial parts of Lycopodiastrum casuarinoides resulted in the isolation of three new lycodine alkaloids, 16-hydroxy-9-oxo-lycocasuarinine D (1), 6α-hydroxy-16-dehydroxy-lycocasuarinine A (2), and 6α,16-dihydroxy-lycocasuarinine B (3). Structural elucidation of all the compounds was performed by spectral methods such as 1D- and 2D-NMR, infrared, ultraviolet, and HR-ESI-MS. The isolated alkaloids were tested in vitro for cytotoxic potential against six lung cancer cell lines. Consequently, alkaloid 1 exhibited cytotoxicity against all the tested tumor cell lines with IC50 values less than 20 μM. [ABSTRACT FROM AUTHOR]

With the development of high-performance fighters, the function of pilot helmets is also constantly upgrading, and helmet-mounted display (HMD) has become a future development trend. To solve the inter-restriction between the eye position control and the pressure comfort under high overloads of pilot helmets, this paper optimizes the helmet design by building a head-helmet finite element model: (1) Under a 10 G overload, the deformation of helmet soft liner should not exceed 2 mm; and (2) The combination of liner materials used in various areas should satisfy the requirements of most comfortable head pressure distribution (Pfront: Ptop: Pside: Pback = 2:2:1:3). The study on 46 different combinations of materials finds that the helmet can meet both the eye position maintenance requirement under overloads and the requirement of comfortable pressure distribution when linear elastic materials with Young’s modulus of 1000 pa, 55000 pa and 65000 pa are used for the side, top and front parts of the head, and nonlinear elastic hyperfoam material with two-fold stress variation is used for the head back area. [ABSTRACT FROM AUTHOR]

Aim: To investigate the protective effect of hypothermia (HT) on brain injury in moderate traumatic brain injury (TBI) rat models and the potential mechanisms, especially the involvement of RIPK1 in apoptosis and necroptosis. Methods: Adult Sprague-Dawley rats were randomized to four groups: sham+normothermia (sham+NT), sham+hypothermia (sham+HT), moderate TBI+normothermia (TBI+NT) and moderate TBI+hypothermia (TBI+HT). The sham+HT and TBI+HT groups were submitted to 32°C for 6 hours. The regional cerebral blood flow (rCBF) was assessed 24 hours after TBI; 24 and 48 hours after TBI, the modified neurological severity score (mNSS) was assessed. Immediately after behavioural tests, rats were sacrificed to harvest the brain tissues. Results: mNSS scores were lower in the TBI+HT group compared with the TBI+NT group (p < 0.01) and cerebral blood flow was better (p < 0.01). H&E staining of the cortex and ipsilateral hippocampus showed pyknotic and irregularly shaped neurons in TBI+NT rats, which were less frequent in TBI+HT rats. The TBI+NT and TBI+HT groups showed higher TNF-α, TRAIL, FasL, FADD, caspase-3, caspase-8, PARP-1, RIPK-1 and RIPK-3 levels than the sham+NT group (all p < 0.05), but the levels of these proteins were all lower in the TBI+HT group compared with the TBI+NT group (all p < 0.01). Conclusion: HT treatment significantly reduced RIPK-1 upregulation, which may inhibit necroptosis and apoptosis pathways after moderate TBI. [ABSTRACT FROM AUTHOR]

To investigate the effects ofβ-carboxyethyl germanium sequioxide (Ge-132) and germanium dioxide (GeO2) on improving salt tolerance of evening primrose (Oenothera biennisL.), seed germination, seedling growth, antioxidase and malondialdehyde (MDA) were observed under treatments of various concentrations (0, 5, 10, 20, 30 μM) of Ge in normal condition and in 50 mM NaCl solution. The results showed that both Ge-132 and GeO2treatments significantly increased seed germination percentage and shoot length in dose-dependent concentrations but inhibited early root elongation growth. 5–30 μM Ge-132 and 10, 20 μM GeO2treatments could significantly mitigate even eliminate harmful influence of salt, representing increased percentage of seed germination, root length, ratio between length of root and shoot, and decreased shoot length. These treatments also significantly decreased peroxidase (POD) and catalase (CAT) activities and MDA content. The mechanism is likely that Ge scavenges reactive oxygen species – especially hydrogen peroxide (H2O2) – by its electron configuration 4S24P2so as to reduce lipid peroxidation. This is the first report about the comparison of bioactivity effect of Ge-132 and GeO2on seed germination and seedling growth under salt stress. We conclude that Ge-132 is better than GeO2on promoting salt tolerance of seed and seedling. [ABSTRACT FROM AUTHOR]

The complete chloroplast genome of Youngia gracilipes was identified. Here, we sequenced and annotated complete chloroplast genome of Youngia gracilipes. The whole genome length is 152,811 bp, including a large single-copy (LSC) region with length of 84,337 bp, a small single-copy (SSC) region with length of 18,392 bp, a pair of inverted repeat (IR) regions with length of 25,041 bp. A total of 114 unique genes was found, of which 80 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Simultaneously, molecular phylogenetic analysis suggested that Youngia gracilipes was the closest to Youngia japonica. [ABSTRACT FROM AUTHOR]

The Michael reactions of indole and pyrrole compounds to α,β-unsaturated ketones catalyzed by triflic acid (HOTf, 0.1–1 mol%) were performed in water to give alkylated indoles (3a–m) and dialkylsubstituted pyrroles (6a–b) in good to excellent yields. [ABSTRACT FROM AUTHOR]