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OBJECTIVE: Acute liver injury (ALI) is mainly characterized by the symptom of metabolic disorders, homeostasis unbalance, and loss of liver function. There are no effective treatment methods at present stage except the liver transplantation. Effective treatment for early ALI is of great significance for the treatment of liver injury thereof. Glycyrrhizin (GL) is a promising inhibitor of the high-mobility group box-1 gene (HMGB1) which is expressed much higher in an inflammatory injury. However, it is not clear whether GL improves ALI via the inhibition of HMGB1. The present study is to probe the function and mechanism of glycyrrhizin on acute liver injury. MATERIALS AND METHODS: The expression of HMGB1 and inflammation in liver macrophages were analyzed. Lipopolysaccharide (LPS) was used in stimulating the macrophages to activate inflammatory response and recombined human HMGB1 was used to resist the function of GL to explore whether GL acted via the target of HMGB1. Then, LPS injection was utilized to induce ALI in mice, and then we evaluated GL treatment in ALI model. RESULTS: The results showed that the expressions of HMGB1 and inflammatory factors were markedly increased in LPS-activated liver macrophages. GL inhibited the progress of macrophages inflammation by restraining HMGB1, and the administration of GL could reverse the effects of LPS-induced ALI in mice. Moreover, PI3K/mTOR pathway was significantly suppressed by GL application. CONCLUSIONS: These results suggest that GL prevents inflammation in liver macrophages via inhibition of HMGB1. GL restrains inflammation and cell apoptosis by inhibiting HMGB1 via PI3K/mTOR signaling pathway in ALI. GL may become a novel drug for the therapy of ALI in the future. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) plays an important role both to condition soil properties and to mitigate climate change. SOM change pattern after intensive tillage is still not well revealed. Taking Sanhu Farm, Jiangling County, Hubei Province, China as a case area, based on topsoil survey samples of 1990, 1994 and 2000 respectively, the spatial distribution pattern and temporal change of SOM content was analyzed. The results show that (1) SOM content successively decreased with the increase of land exploitation history; (2) topsoil SOM value of the three survey years showed a similar spatial pattern whereby the highest SOM value was distributed in the center, and SOM value decreased incrementally as the distance from the center increased, which showed the SOM values were negatively correlated to the altitude of study area; (3) there was an overall tendency for the maximum or minimum value of SOM to approach to the average value over time; (4) SOM concentration changes were influenced by crop systems changes related to the price of crops and related policies. The study depicts SOM variability after the reclamation from virgin land to arable land at a landscape scale, which may contribute to research revealing spatial distribution patterns and controlling elements of SOM change. [ABSTRACT FROM AUTHOR]

Soluble starch synthase II (SSII) plays an important role in the biosynthesis of starch and in rice it consists of three isoforms encoded by SSII-1, SSII-2 and SSII-3. However, the genetic effects of various SSII alleles on grain quality have not been systematically characterized. In the present study, the japonica alleles on SSII-1, SSII-2 and SSII-3 (SSIIa) loci from a japonica cultivar, Suyunuo, were respectively introgressed by molecular marker-assisted selection into a typical indica cultivar, Guichao2, through successive backcrossing, generating three sets of near-isogenic lines (NILs). Grain quality and starch property analysis showed that NIL-SSII-3j exhibited significant decreases in the following parameters: amylose content, average granule size, and setback viscosity and consistency; but increases in peak viscosity, hot paste viscosity, gelatinization temperature and relative crystallinity. Moreover, the proportion of short amylopectin chains and branching degree also increased when compared with those of NIL-SSII-3i (Guochao2). Similar effects were observed in NIL-SSII-1j, and certain alterations in the fine structure of starch (granule size) were revealed. However, NIL-SSII-2j did not exert significant effect on grain quality and starch properties. In brief, among the SSII gene family, the functional diversity occurred on SSII-1 and SSII-3, and not on SSII-2. Therefore, it appears that more attention should be directed to SSII-1 and SSII-3 loci for improving the eating and cooking quality of rice. [ABSTRACT FROM PUBLISHER]

A new pore forming process for the casting of microarray holes in Al components was proposed. This pore forming process depended on both the poor wettability of C and Al, and high strength of extension of carbon fibre. In contrast to conventional pore forming methods, such as mechanical or special process, the proposed method did not require any additional sophisticated equipment and acquired super large aspect ratio by casting. Aiming at demonstrating the feasibility and making comparative superiority of the proposed pore forming method, pore forming principle and the regularities of aperture were studied. The results show molten aluminium pore formed around the carbon fibre bundle. The actual diameter of holes is almost 20% larger than that of the theoretical value, the average aspect ratio of holes reaches 290 and the average diameter of holes is ~0·222 mm under the influence of loose quantity. [ABSTRACT FROM AUTHOR]

Samples of the (Mg0.585Cu0.305Y0.11)97(Zr0.35Ti0.3Be0.275Cu0.075)3 bulk metallic glass (BMG) with 3mm in diameter were successfully fabricated by copper mould casting method. The amorphous nature, thermal stability, microstructure and mechanical properties of the alloy were investigated by using X-ray diffraction (XRD), differential scanning calorimeter (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electronic testing machine. The results show that the alloy presents a fully amorphous structure containing two glassy phases caused by phase separation. The Zr-rich amorphous spherical phase is distributed in the Mg-rich glassy matrix of the as-cast sample. Under uniaxial compressive loading, the compressive fracture strength, elastic strain and plastic strain of the BMG with a diameter of 3mm are 1026MPa, 2.2% and 0.3%, respectively. The ridge form vein-like patterns and multiple shear bands are observed in the fracture surface, indicating the improvement of the mechanical properties of the alloy. The formation of phase separation and the corresponding fracture mechanism were discussed. [ABSTRACT FROM AUTHOR]

F1 progenies of a genic male sterile and early maturing indica line 6442S-7 crossed with sixteen medium or late maturing varieties, such as Minghui 63, shared the same heading date as 6442S-7 under long day and short day, suggesting that 6442S-7 has completely dominant earliness. Segregation of heading dates of the F2 and B1F1 populations indicated that the earliness of 6442S-7 is mainly controlled by two dominant major genes. Whereas, heading dates of F1 progenies of 6442S-7 crossed with other four late maturing varieties, i.e. IR68, Xianguo, 9311, and BG1639, closed to the mid-parent value under long day. In F2 populations of 6442S-7 crossed with each of the four late maturing varieties, F1 from three-way crosses between 6442S-7 and each F1 of Minghui 63 crossed with each of the four late maturing varieties, and F1 from three-way crosses between 6442S-7 and each F1 of crosses between each two of the four late maturing varieties, segregation of heading dates showed that an incompletely diminant allelic suppressor for the dominant earliness of 6442S-7 existed in the late maturing varieties, IR68, Xianguo, 9311, and BG1639. It is considered that dominant earliness genes harbored in 6442S-7 have splendid future in rice improvement.

We report the generation of sub-Poissonian pulses of light by means of traveling-wave second-harmonic generation (SHG) in a type II phase-matched nonlinear crystal. On direct detection, the quantum noise on the output light, which is polarized orthogonally to the input fundamental field, is measured to be below the shotnoise limit by as much as 0.3 +/- 0.2 dB (6 +/- 4%). We show that the input fundamental-power dependence of the measured Fano factor, direct-detection noise as a fraction of the shot-noise limit, is in qualitative agreement with the quantum theory of SHG.

SP-6 was synthesized by solid phase method in 95% purity on HPLC. The data obtained from amino acid analysis and fast atom bombardment were in good agreement with theoretical values. Intravenous injection of SP-6 in rabbits at the dosage of 14.3 micrograms/kg. resulted in blood pressure reduction of 4.4 kPa, i.e. 34% (P < 0.001). When the concentration of SP-6 in Tyrode solution was 5.2 x 10(-4) mg/ml the contraction of rabbit duodenum longitudinal muscle increased by 105%. (P < 0.001). When the concentration was more than 1 x 10(-3) mg/ml, the contractile effect was restrained significantly. Dropping 30 microliters of SP-6 (1 x 10(-3) mg/ml) to toad intestinum tenue mesenteriale in situ, the mesentery arterioles were expanded by 30%.

We have analyzed squeezing of the fundamental field by means of traveling-wave, type-II phase-matched, secondharmonic generation, taking into account depletion of the fundamental field and phase mismatch between the fundamental and the harmonic fields. For the phase-matched case we show that the generated squeezing is S = 1 - gamma, where gamma is the harmonic conversion efficiency. In the case of a large phase-mismatch we have identified a new mechanism that generates squeezing. It is the nonlinear phase shift of the fundamental field that is due to the cascaded chi((2)) nonlinearity.

We analyze pulse propagation in a nonlinear optical fiber in which linear loss in the fiber is balanced by a chain of periodically spaced, phase-sensitive, degenerate parametric amplifiers. Our analysis shows that no pulse evolution occurs over a soliton period owing to attenuation in the quadrature orthogonal to the amplified quadrature. Evidence is presented that indicates that stable pulse solutions exist on length scales much longer than the soliton period. These pulses are governed by a nonlinear fourth-order evolution equation, which describes the exponential decay of arbitrary initial pulses (within the stability regime) onto stable, steady-state, solitonlike pulses.

Electron microscopy of purified Chlamydia trachomatis treated by various physical and chemical means shows that the envelope of the elementary bodies (EB) consists of the outer cell wall layer, the inner cell wall layer, and the inner membrane. The outer cell wall layer is mainly made up of granular subunits arranged in a hexagonal pattern and may be called the "mural structural protein layer". It forms together with the inner cell wall layer the rigid cell wall. The inner or protoplasmic membrane is not easily shown in the young EB. In the negatively stained specimen, a frail and easily removable superficial layer is seen adhering to the "mural structural protein layer". But in ultra-thin sections this superficial layer is not shown separately. There are fold-like grooves which are special structures probably related to reproduction. There are seen some EB's in binary fission, and a number of bodies very big in size yet having morphological characteristics of the EB's, which are in various processes of multiplication, such as binary fission, budding, and "multicentered germination". These observations give a challenge to the current opinion that only the initial bodies have the power of reproduction.