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Two new triterpenoid saponins (

By HPLC-MS

Depression is a psychiatric disorder that presents with a persistent depressed mood as the main clinical feature and is accompanied by cognitive impairment. Changes in neuroplasticity and neurogenesis greatly affect depression. Without genetic changes, epigenetic mechanisms have been shown to function by regulating gene expression during the body’s adaptation to stress. Studies in recent years have shown that as important regulatory factors in epigenetic mechanisms, microRNAs (miRNAs) play important roles in the development and progression of depression through the regulation of protein expression. Herein, we review the mechanisms of miRNA-mediated neuroplasticity in depression and discus synaptic structural plasticity, synaptic functional plasticity, and neurogenesis. Furthermore, we found that miRNAs regulate neuroplasticity through several signalling pathways to affect cognitive functions. However, these pathways do not work independently. Therefore, we try to identify synergistic correlations between miRNAs and multiple signalling pathways to broaden the potential pathogenesis of depression. In addition, in the future, dual-function miRNAs (protection/injury) are promising candidate biomarkers for the diagnosis of depression, and their regulated genes can potentially be used as target genes for the treatment of depression.

To explore the dynamic impacts of simulated microgravity (SM) on different vital brain regions of rats.Microgravity was simulated for 7 and 21 days, respectively, using the tail-suspension rat model. Histomorphology, oxidative stress, inflammatory cytokines and the expression of some key proteins were determined in hippocampus, cerebral cortex and striatum.21-day SM decreased brain derived neurotrophic factor and induced neuron atrophy in the cerebral cortex. Strong oxidative stress was triggered at day 7 and the oxidative status returned to physiological level at day 21. Inflammatory cytokines were gradually suppressed and in striatum, the suppression was regulated partially through c-Jun/c-Fos.The results revealed that the significant impacts of SM on rat brain tissue depended on durations and regions, which might help to understand the health risk and to prevent brain damage for astronauts in space travel.

A 2xVDD output buffer with process and voltage (PV) compensation technique is proposed to keep slew rate (SR) within predefined ranges regardless PV variations. The reason of temperature variation is not considered is that it is found to be relatively low correlated to slew rate for 90 nm process or better. All bias voltages in process and voltage variation detectors are generated from bandgap circuits such that variations have been guaranteed by simulation within less than 4.10%. The data rate is 650/500 MHz given 1.0/2.0 V supply voltage with 20 pF load, respectively, by physical measurements. The Δ SR improvement is 30.7% and 31.4% for 1× VDD and 2× VDD, respectively, when the proposed PV compensation design is activated.

OBJECTIVE: To investigate the effect of androgen receptor (AR) on IgG protein expression and the proliferation and migration of prostate cancer cells. METHODS: Western blotting was used to detect the expression of AR protein and IgG in androgen-dependent prostate cancer LNCap cells and castration-resistant prostate cancer PC-3 cells. In AR-overexpressing cells (PC-3-AR cells) established by transfecting PC-3 with AR gene (pCDNA3.1) and LNCap cells with small interfering RNA-mediated AR silencing (LNCap-siAR cells) were analyzed for expressions of AR protein and IgG with Western blotting; the expression of IgG mRNA was detected by Q-PCR, and the cell proliferation and migration were assessed with MTT assay and wound healing assay, respectively. RESULTS: Compared with PC-3 cells, LNCap cells expressed a higher level of AR protein and a lower level of IgG (P < 0.05). PC-3-AR cells showed attenuated proliferation and migration with a lowered expression of IgG (P < 0.01), while LNCap-siAR cells showed enhanced proliferation and migration with increased expression of IgG (P < 0.01). CONCLUSION: The expression of AR is inversely correlated with IgG and is associated with the proliferation and migration of prostate cancer cells in vitro.

A 2[Formula: see text]VDD CMOS output buffer with process, voltage and leakage (PVL) detection mechanism is proposed such that slew rate is auto-adjusted to reduce the variations at different corners. To boost the driving current, low threshold voltage transistors are used instead of devices with typical threshold voltage in the driving transistor of output stage. More importantly, to prevent large leakage of those large low threshold voltage devices, leakage detection resistors are added at the gates of the always-on low threshold voltage transistors to clamp the leakage. The static power consumption is reduced when it is not activated. Another feature of the proposed design is that the gate-oxide leakage is also reduced by lengthening the driving transistors. Besides, all biases in the proposed design are generated from bandgap circuits such that not only is the variation caused by temperature drifting reduced, the area overhead and power dissipation are also minimized. The proposed design is carried out by using 28-nm CMOS process. The data rate proved by physical measurement is proved to be 2.0[Formula: see text]GHz given 1.8/1.05[Formula: see text]V supply voltage, namely, VDD or 2[Formula: see text]VDD, when the proposed PVL detection as well as the compensation circuitry are activated.

The chiral separations of four pharmaceutical racemates which contain N -alkyl groups were satisfactorily resolved using SBE- β -CD as a chiral mobile phase additive (CMPA) in a RP-HPLC system (the resolution is 2.701 for ondansetron hydrochloride, 1.996 for sulpiride, 1.293 for clenbuterol hydrochloride and 0.816 for omeprazole). In addition, the effects of different parameters such as CD type and CD concentration were investigated. The separation mechanism arises through the combination of several potential interactions, including electrostatic interactions as well as hydrogen bonding interactions and hydrophobic inclusion interactions, which allow for the SBE- β -CD–drug complexation with strong stereoselectivity and stability. The resolution also relates to the number and location of N atoms in the enantiomers. This method will be applicable to the isolation of various types of biologically important enantiomers containing N -alkyl groups.

The configuration and aerodynamics performance of the inlet system are important aspects in the process of gas turbine installation on naval vessels. Under the requirements, using CFD method simulated four kinds of structure cyclone flow field of the marine gas turbine intake filters, found the lowest flow resistance structure, then verified by experiment. Through comparison, the numerical simulation results agree with experimental study well. The methods used in the article have some reference significance for the design of the inlet system.

The enantiomers separation of eight pharmaceutical racemates collected in Chinese Pharmacopoeia 2010 (Ch.P2010), including nitrendipine, felodipine, omeprazole, praziquantel, sulpiride, clenbuterol hydrochloride, verapamil hydrochloride and chlorphenamine maleate, was performed on chiral stationary phase of amylose ramification by high performance liquid chromatography (HPLC) on Chiralpak AD-H column and Chiralpak AS-H column with the mobile phase consisted of isopropanol and n-hexane. The detection wavelength and the flow rate were set at 254 nm and 0.7 mL/min, respectively. The effects of proportion of organic additives, alcohol displacer and temperature on the separation were investigated. The results indicated that eight chiral drugs were separated on chiral stationary phase of amylase ramification in normal phase chromatographic system. The chromatographic retention and resolution of enantiomers were adjusted by factors, including the changes of the concentration of alcohol displacer in mobile phase, organic alkaline modifier and column temperature. It was shown that the resolution was improved with reducing concentration of alcohol displacer. When the concentration of organic alkaline modifier was 0.2%, the resolution and the peak shape were fairly good. Most racemates mentioned above had the best resolution at column temperature of 25 °C. The best temperature should be kept unchanged in the process of separation so as to obtain stable separation results.

9α‐(3‐Azabicyclo[3,3,1]nonanyl)‐2′‐cyclopentyl‐2′‐hydroxy‐2′‐phenylacetate (1) was synthesized and its enantiomers were obtained by the optical resolution of racemates with the chiral host N‐p‐toluenesulfonylglutamic acid. Optical pure 1 was also effective diastereoselective synthesized using benzaldehye as steric hindrance agent from the chiral starting material, (S) or (R)‐mandelic acid. The structure of the title compound was first elucidated by X‐ray analysis.

This paper studies red blood cell (RBC) partitioning and blood flux redistribution in microvascular bifurcation by immersed boundary and lattice Boltzmann method. The effects of the initial position of RBC at low Reynolds number regime on the RBC deformation, RBC partitioning, blood flux redistribution and pressure distribution are discussed in detail. It is shown that the blood flux in the daughter branches and the initial position of RBC are important for RBC partitioning. RBC tends to enter the higher-flux-rate branch if the initial position of RBC is near the center of the mother vessel. The RBC may enter the lower-flux-rate branch if it is located near the wall of mother vessel on the lower-flux-rate branch side. Moreover, the blood flux is redistributed when an RBC presents in the daughter branch. Such redistribution is caused by the pressure distribution and reduces the superiority of RBC entering the same branch. The results obtained in the present work may provide a physical insight into the understanding of RBC partitioning and blood flux redistribution in microvascular bifurcation.

To study the suitable oxygen concentration in hypoxic preconditioning.Short-term and long-term intermittent hypoxia modes were designed and the effects of various oxygen concentrations on body weight, blood oxygen saturation, swimming capability were analyzed.The rate of body weight gain in rat model decreased gradually when exposed to hypoxia environment for long time. When the concentration of oxygen changed from 15% to 8%, accompanied with the decreasing of oxygen concentration, a platform was observed in blood oxygen saturation of rat model after hypoxic preconditioning training. Rat swimming capability improved significantly. After trained in 10% hypoxia environment, the swimming capability of kunming mice improved obviously.Proper level of hypoxic preconditioning training could improve hypoxia tolerance and enhance the rat sport capability significantly. 15%-10% oxygen concentration range could be regarded as a helpful effective area for hypoxic preconditioning, 10% oxygen concentration might be the eligible concentration for hypoxic preconditioning training.

This paper analyzes characteristics of human capital property rights (HCPR) of knowledge employees. Using the framework of multi-task principle-agent, we establish the principle-agent model which involves the tasks of hard studying & hard working and the incentive of performance & property rights, then discuss the interaction between performance incentive and property rights incentive, and analyze the effort of hard studying and hard working. The results show that the property rights incentive may promote employees' efforts to work hard and study hard, also optimize the performance incentive mechanism. Knowledge employees have the optimal efficiency if they keep all the surplus value. However the property rights incentive has to match the performance incentive, the stronger property rights incentive, the better. When property rights incentive is taken as a long-term incentive, the employees are willing to study hard. When performance incentive is taken as a short-term incentive, they are apt to work hard. When they are lack of property rights incentive, knowledge employees will not be interest in studying or be inclined to external studying behavior.

To study the flavonoids compounds from the effective fraction of Thesium chinese in anti-inflammation.The isolation and purification were carried out by many kinds of column chromatographic techniques. The flavonoids were analyzed by HPLC-DAD, and elucidated by 1H-NMR, 13C-NMR and ESI-MS.Five compounds were obtained and therir structures were determined as kaempferol-3-O-glucoside (I), rutinoside (II), luteolin-7-O-glucoside (III), kaempferyl 5-methyl ether (IV), apigenin-5-O-neohesperidoside (V).Compounds IV and V are isolated from this plant for the first time.

To establish a determination method of astragulin in Thesium chinese.RP-HPLC analytical method was established using a Polaris C18 column and acetonitrile-water (23:77) as the mobile phase, with a flow rate of 10 mL x min(-1), detected at 346 nm. The method of sample is refluxing exation by 50% alcohol for 2 times.The content of astragulin was from 0. 120% to 0. 155%, in different groups of T. chinese collected from the same location.The method was validated to show convenient and reliable.

Samples extracted from the root of Iris japonica Thunb were analyzed and the optimal HPLC chromatographic conditions was confirmed. Through analyzing the chromatography, the HPLC-FPS of Iris japonica Thunb was established.

(9s)-N-methyl-3-azabicyclo[3.3.1]nonan-9-yl (cyclopentyl)(hydroxy)(2-thienyl)acetate hydrochloride, a more effective muscarinic receptor antagonist, was synthesised and its crystal structure elucidated by X-ray crystallography.

A self-propelled fish swimming in viscous fluid is investigated by solving the incompressible Navier–Stokes equations numerically with the space-time finite element method to understand the mechanisms of aquatic animal locomotion. Two types of propulsion strategies, undulatory body and traveling wave surface (TWS), are considered. Based on the simulations, we find that by performing lateral undulation, the fish is able to move forward with a reverse von Kármán vortex street in its wake. In addition, there is no vortex street in the wake of the fish using TWS. In this case, the thrust of the fish is generated by the jets outside the boundary layer and the high pressure on the leeward side of the traveling wave. The results obtained in this paper will be of help in understanding of the propulsive performance of aquatic animal locomotion.

A two-dimensional red blood cell (RBC) membrane model based on elastic and Euler–Bernoulli beam theories is introduced in the frame of immersed boundary-lattice Boltzmann method (IB-LBM). The effect of the flexible membrane is handled by the immersed boundary method in which the stress exerted by the RBC on the ambient fluid is spread onto the collocated grid points near the boundary. The fluid dynamics is obtained by solving the discrete lattice Boltzmann equation. A "ghost shape", to which the RBC returns when restoring, is introduced by prescribing a bending force along the boundary. Numerical examples involving tumbling, tank-treading and RBC aggregation in shear flow and deformation and restoration in poiseuille flow are presented to verify the method and illustrate its efficiency. As an application of the present method, a ten-RBC colony being compressed through a stenotic microvessel is studied focusing the cell–cell interaction strength. Quantitative comparisons of the pressure and velocity on specified microvessel interfaces are made between each aggregation case. It reveals that the stronger aggregation may lead to more resistance against blood flow and result in higher pressure difference at the stenosis.