Description: 3-Oxotaraxer-14-en-30-al ( 1 ), a new taraxastane-type triterpene, together with 14 known compounds, taraxerone ( 2 ), 3-epiursolic acid ( 3 ), 2 α ,3 β -dihydroxyurs-12-en-28-oic acid ( 4 ), lupeol ( 5 ), betulinic acid ( 6 ), casticin ( 7 ), artemetin ( 8 ), luteolin ( 9 ), 4-hydroxybenzoic acid ( 10 ), docosanoic acid ( 11 ), tetracosanoic acid ( 12 ), cerotic acid ( 13 ), β -sitosterol ( 14 ), and β -daucosterol ( 15 ), was isolated from the leaves and twigs of Vitex trifolia var. simplicifolia . Compounds 2 – 6 were found for the first time in this plant. Their structures were established by spectroscopic analysis, including 2D-NMR techniques. Cytotoxic activities of compounds 3 , and 5 – 10 were tested on the three cancer cell lines, PANC-1, K562, and BxPC-3. Results revealed that 7 exhibited cytotoxicity against PANC-1, K562, and BxPC-3, with IC 50 values of 4.67, 0.72, and 4.01 μg/ml, respectively, whereas 8 was inactive against these cancer cell lines. The structure activity relationship of compound 7 and 8 indicated that the 3′-OH group in polymethoxyflavonoids is essential for antitumor activity.

Description: G protein-regulated cell function is crucial for cardiomyocytes, and any deregulation of its gene expression or protein modification can lead to pathological cardiac hypertrophy. Herein, we report that protein prenylation, a lipidic modification of G proteins that facilitates their association with the cell membrane, might control the process of cardiomyocyte hypertrophy. We found that geranylgeranyl diphosphate synthase (GGPPS), a key enzyme involved in protein prenylation, played a critical role in the postnatal heart growth through regulating the cardiomyocyte size. Cardiac-specific knockout of GGPPS in mice led to spontaneous cardiac hypertrophy beginning from 4 th week, accompanied with the persistent enlargement of cardiomyocytes. This hypertrophic effect occurred by altered prenylation of G proteins. Evaluation of the prenylation, membrane association and hydrophobicity showed that Rheb was hyperactivated and increased mTORC1 signaling pathway after GGPPS deletion. Protein farnesylation or mTORC1 inhibition blocked GGPPS knockdown-induced mTORC1 activation and suppressed the larger neonatal rat ventricle myocyte size and cardiomyocyte hypertrophy in vivo , demonstrating a central role of FPP/Rheb/mTORC1 axis for GGPPS deficiency-induced cardiomyocyte hypertrophy. The sustained cardiomyocyte hypertrophy progressively provoked cardiac decompensation and dysfunction, ultimately causing heart failure and adult death. Importantly, GGPPS was downregulated in the hypertrophic hearts of mice subjected to transverse aortic constriction (TAC) and in the failing human hearts. Moreover, HPLC-MS/MS detection revealed that myocardial farnesyl diphosphate (FPP) to geranylgeranyl diphosphate (GGPP) ratio was enhanced after pressure overload. Our observations conclude that the alteration of protein prenylation promotes cardiomyocyte hypertrophic growth, which acts as a potential cause for pathogenesis of heart failure and may provide a new molecular target for hypertrophic heart disease clinical therapy.

Description: A traffic flow Lighthill, Whitham, and Richards (LWR) model is studied by means of a proper orthogonal decomposition (POD) technique. A POD-based reduced-order finite difference (FD) extrapolating algorithm (FDEA) with lower dimension and fully second-order accuracy is established. Two numerical experiments are used to show that the POD reduced-order FDEA is feasible and efficient for finding numerical solutions of traffic flow LWR model.MSC: 76M20, 65M12, 65M15.

Description: We show that a carbon nanotube (CNT) diode fabricated by asymmetric contacts shows a linear photocurrent in response to illumination for over six decades or dynamic range of 120 dB; in particular, it shows no sign of degradation under illumination intensity of up to 100 kW/cm 2 . This CNT diode also exhibits a continued response for incident wavelength from 1165 nm to 2100 nm, promising potentials applications in robust and wide bandwidth light sensing.