Effect of Sowing Date on the Growth Characteristics and Yield of Growth-Constrained Direct-Seeding Rice.

To investigate changes in the yield and physiological characteristics of indica hybrid rice varieties sown on different dates, we evaluated appropriate hybrid rice varieties and their optimal sowing dates in the hilly areas of Sichuan. Three popular indica rice varieties were used as experimental materials, and five sowing dates were set uniformly locally [16 May (SD1), 23 May (SD2), 30 May (SD3), 6 June (SD4), and 13 June (SD5)] to investigate differences in the yield characteristics, growth period, and dry matter accumulation. The results showed that, over the two years, the sowing-to-heading period and overall growth period of the three varieties shortened as the sowing date was delayed, and the difference in yield between the SD1 and SD2 treatments was not significant, owing to higher material accumulation after flowering and higher assimilative material transport capacity. These varieties are both photosensitive and tolerant to low temperatures. Among the three varieties tested, the Huangyouyuehesimiao (V3) cultivar had the highest yield, with 10.75 t ha-1 under the SD2 treatment. The impact of shifting the sowing date on yield components varied. Delaying the sowing date increased and then decreased the number of effective panicles, and the number of grains per panicle and the seed setting rate decreased by differing degrees. In summary, a high yield of indica hybrid rice can be maintained by sowing between 16 and 23 May each year in the study area. It indicated that indica hybrid rice in the hilly rice-producing region of Sichuan is highly adaptable to different sowing dates.

Isolation and anti-fatty liver activity of a novel cerebroside from the sea cucumber Acaudina molpadioides.

Cerebrosides are a kind of important bioactive substance in sea cucumber. A novel cerebroside, AMC-2, was purified from the less-polar lipid fraction of the sea cucumber Acaudina molpadioides by repeated column chromatography. The major structure of AMC-2 was analyzed by gas chromatography-mass spectra. The amide-linked fatty acid unit was confirmed to be four saturated and monounsaturated α-hydroxy fatty acids, the long-chain base was dihydroxy sphingoid base with one double bond, and the glycosyl group was glucose. We also investigated the anti-fatty liver activity of AMC-2 in rats with fatty liver induced by orotic acid. AMC-2 significantly reduced hepatic triglyceride (TG) and total cholesterol (TC) levels at a diet supplement of 0.03% and 0.006%. The indexes of stearoyl-CoA desaturase (SCD) activity and mRNA expression were significantly decreased by AMC-2. This indicates that AMC-2 ameliorated nonalcoholic fatty liver disease (NAFLD) through suppression of SCD activity and impaired the biosynthesis of monounsaturated fatty acids in the livers of the rats.

[Effect of sea cucumber cerebroside on lipid metabolism in fatty liver rats].

OBJECTIVE: To investigate the effect of sea cucumber cerebroside (SCC) on the lipid metabolism in rats with orotic acid-induced fatty liver. METHODS: The non-alcoholic fatty liver disease (NAFLD) model was established by adding orotic acid to the diets in rats. The rats were randomly assigned to four groups:control group, NAFLD group, NAFLD + low SCC group and NAFLD + high SCC group. After 10 days of feeding, the serum and hepatic lipid concentrations and the aminopherase activities were measured; the composition of hepatic fatty acids was also analyzed. RESULT: The serum TC and TG levels reduced significantly in the NAFLD group as compared with the controls (P<0.05), while the sea cucumber cereborside feeding raised the serum lipid concentrations (P<0.05). The hepatic TC and TG levels dramatically increased in the NAFLD group in comparison with the controls (P<0.05, P<0.01), while the hepatic lipid accumulations decreased in both SCC groups (P<0.05, P<0.01). The ALT and AST activities in the NAFLD group increased markedly when compared with the controls (P<0.05, P <0.01), while the sea cucumber cerebroside feeding attenuated the hepatic injury levels (P<0.05, P<0.01). Compared with the control group, the stearoyl-CoA desaturase (SCD) activity increased significantly in the NAFLD group (P<0.05), but decreased in SCC groups (P<0.05). CONCLUSION: Sea cucumber cerebroside can attenuate the rat fatty liver induced by orotic acid.

Advances in research on the role of nitric oxide in regulating sleep and arousal / 药学学报

Nitric oxide (NO) is widely present in peripheral and central nervous system and regulates many physiological functions. Sleep-arousal is an advanced physiological activity. Studies have shown that NO is involved in the regulation of sleep and arousal. Nitric oxide synthases (NOSs) are a family of enzymes that catalyze the production of NO from L-arginine. Through guanylate cyclase or S-nitrosation of protein, NO can affect the activity of the ascending reticular activating system to regulate the sleep-arousal process. This paper summarizes the production of NO, its effect on sleep-arousal and its mechanism in the ascending reticular activating system, and provides new ideas and directions for the study of sleep and arousal.

Regulatory effect and mechanism of novel sedative hypnotic compound YZG-331 on glutamate and its receptor / 药学学报

This study investigated the effect of a novel adenosine derivative YZG-331 on the glutamate (Glu) content and its receptor N-methyl-D-aspartate receptor (NMDAR) in mouse frontal cortex. All procedures in this research were approved by the Institutional Animal Care and Use Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences. High performance liquid chromatography (HPLC) was used to detect the Glu contents in the mouse frontal cortex tissue homogenate and extracellular fluid which were collected by brain microdialysis method. Western blot and co-immunoprecipitation methods were used to detect the expressions of NMDAR in cell membranes and endosomes, as well as the expression levels of endocytosis-related proteins and their interaction. The results showed that there was no significant change in Glu content in the dialysates from mouse frontal cortex within 0-0.5 h period and 0.5-1 h period after intragastric administration of YZG-331 (40 mg·kg-1). Compare to the control group, the Glu content in mouse frontal cortex homogenates has no significant statistical differences after 15 minutes of administration of compound YZG-331. YZG-331 significantly decreased the expressions of NMDAR subunits NR1 and NR2B in the mouse frontal cortex cell membrane, meanwhile significantly increased the expressions of NR1 and NR2B proteins in the frontal cortex endosomes. It also increased the phosphorylation levels of NMDAR subunit NR2B in the frontal cortex. In addition, the result of co-immunoprecipitation which used NR2B as bait protein showed that the expression of postsynaptic density-95 (PSD95) in NR2B and PSD95 immunoprecipitation complexes in mouse frontal cortex tissues was significantly reduced. These results indicate that YZG-331 does not affect the Glu content in mouse frontal cortex, but it weakens the interaction between NR2B and PSD95 by increasing the phosphorylation level of NR2B in the mouse frontal cortex. Therefore, it reduces the membrane stability of NMDAR and promotes NMDAR's endocytosis, which leading to the decrease of excitotary transmission. It may be one of the mechanisms of YZG-331 to exert sedative and hypnotic effects.