[Spatial-temporal trend of grassland net primary production and their driving factors in the Loess Plateau, China]. / é»„åœŸé«˜åŽŸè‰åœ°å‡€åˆçº§ç”Ÿäº§åŠ›æ—¶ç©ºè¶‹åŠ¿åŠå ¶é©±åŠ¨å› ç´ .

Net primary productivity (NPP) of grassland is a key link and important part of the ecosystem's carbon cycle. We estimated the changes of NPP in grasslands of the Loess Plateau with unchanged land use types during 2000-2015 and analyzed its responses to the variation of main climate factors (annual precipitation, annual heavy rainfall, annual effective rainfall days, annual average temperature, annual maximum temperature, annual minimum temperature) using piecewise linear regression and Pearson correlation analysis. The driving factors of grassland NPP were further analyzed by pixel-by-pixel with boosted regression tree analysis. The results showed that annual mean grassland NPP in the Loess Plateau showed an increasing trend during the study period, with 51.3% of the total grassland area showing a significant increasing trend. The average increase rate of annual mean NPP declined from 15.23 g C·m-2·a-1 in 2000-2004 to 3.58 g C·m-2·a-1 in 2004-2015. There was a significant positive correlation between grassland NPP and precipitation, but negative correlation with temperature factors. Annual precipitation was the dominant climatic factor affecting NPP of the whole study area with the highest relative importance. Annual maximum temperature was the dominant driving force of grassland NPP of central Loess Plateau, while annual minimum temperature mainly affected the growth of grassland in high-altitude area of the western Loess Plateau.

[Identification of chemical constituents in Guizhi Fuling Capsules by UPLC-Q-TOF-MS/MS].

To qualitatively characterize the chemical composition of Guizhi Fuling Capsules using UPLC-ESI-Q-TOF-MS/MS. The analysis was performed on Agilent ZORBAX RRHD Eclipes Plus C_(18)(2.1 mm×100 mm, 1.8 µm) column,that was eluted with mobile phase consisting of acetonitrile and 0.1% formic acid in a gradient mode. The flow rate was 0.4 mL·min~(-1), and column temperature was 30 ℃. Tandem mass spectrometry was acquired in both negative and positive ESI modes. These components were further analyzed based on high-resolution mass-to-charge ratios, fragment ion species, reference substances and literature data. In conclusion, a total of 200 compounds were identified, in which 40 were verified with reference substances. The current study laid a foundation for in-depth studies of its mass balance and pharmacodynamics.

Berberine Ameliorates Oxygen-glucose Deprivation/Reperfusion-induced Apoptosis by Inhibiting Endoplasmic Reticulum Stress and Autophagy in PC12 Cells.

This study aimed to elucidate the molecular mechanisms by which berberine protects against cerebral ischemia/reperfusion (I/R) injury. The oxygen-glucose deprivation/reperfusion (OGD/R) PC12 model was established. Cell counting kit-8 (CCK-8) was used to detect the toxicity of berberine and the viability of PC12 cells. Hoechst 33258 staining and flow cytometry were used to observe the nuclear morphology, and changes of apoptosis and reactive oxygen species (ROS), respectively. Western blotting and immunofluorescence assay were employed to detect autophagy-related proteins [microtubule-associated protein 1A/1B-light chain 3 (LC3), P62/SQSTM-1, Beclin-1] and endoplasmic reticulum (ER) stress-related markers [glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), Bcl-2-associated X (Bax) and cleaved caspase-3]. The GFP-RFP-LC3 adenovirus was used to assay the change of autophagic flux. Our results showed that berberine could increase the viability of PC12 cells, decrease the concentrations of ROS after OGD/R treatment, and suppress OGD/R-induced ER stress and autophagy. Moreover, the results revealed the involvement of the mammalian target of rapamycin (mTOR) pathway in the induction of autophagy, and berberine could activate the phosphorylation of mTOR and thus mitigate autophagy. In conclusion, our study suggested that berberine may protect against OGD/R-induced apoptosis by regulating ER stress and autophagy, and it holds promises in the treatment of cerebral I/R injury.

[Research Progress on Role of Gene Mutations in Prognostic Evaluation of Patients with Myelodysplastic Syndrome after Stem-Cell Transplantation--Review].

Abstract　　Myelodysplastic syndromes (MDS) represent a clonal hematopoietic stem cell disorder characterized by morphologic features of dyspoiesis, high risk of transformation from MDS into AML. Allogeneic hematopoietic stem-cell transplantation is the only curative therapy for MDS, but the failure rate of transplantation is still high, which attribute to relapsed disease and transplant-related complications. Recently, the spectrum of gene abnormalities in MDS has been revealed by next generation genomic sequencing techniques. It was found that more than 80% MDS patients have at least one gene mutation. Mutated genes in MDS are powerfully associated with clinical phenotype and prognosis. In this review , the recent advancements regarding recurrent gene mutations in MDS are briefly summarized, and the  prognostic values of gene mutations are discussed in MDS or after allogeneic hematopoietic stem-cell transplantation,so as to set up a predicting model and to guide the treatment.

Two new labdane diterpenoids from aerial parts of Leonurus japonicus and their anti-inflammatory activity.

Two new labdane diterpenoids, Leojaponin E (1) and F (2), together with three known compounds were isolated from the dried herb of Leonurus japonicus Houtt., Lamiaceae. Their structures were determined based on extensive spectroscopic analyses. The absolute configurations of 1 and 2 were elucidated on the basis of experimental and calculated electronic circular dichroism spectra. In addition, compounds 1 and 2 exerted inhibition of LPS-induced PGE2 production in a dose-dependent manner at concentrations ranging from 5 to 20 µM.

[A new aurone with anti-inflammatory activity from Cleistocalyx operculatus flower buds].

A new compound(Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone was isolated from Cleistocalyx operculatus flower buds. Its structure was identified by spectroscopic data including MS, ¹H-NMR, ¹³C-NMR HSQC and HMBC. A known compound, 2',4'-dihydroxy-6'-methoxy-3'5'-dimethylchalcone (DMC), was also isolated and identified,and used as material to synthesize (Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone.Anti-inflammatory activities of the two compounds were tested in vitro. The results showed that (Z)-6-hydroxy-4-methoxy-5,7-dimethylaurone possesses much stronger PGE2 inhibitory activity (IC50 6.12 nmol·L⁻¹) than the positive control ibuprofen （68.66 nmol·L⁻¹ï¼‰.

Brønsted acid-catalysed enantioselective construction of axially chiral arylquinazolinones.

The axially chiral arylquinazolinone acts as a privileged structural scaffold, which is present in a large number of natural products and biologically active compounds as well as in chiral ligands. However, a direct catalytic enantioselective approach to access optically pure arylquinazolinones has been underexplored. Here we show a general and efficient approach to access enantiomerically pure arylquinazolinones in one-pot fashion catalysed by chiral phosphoric acids. A variety of axially chiral arylquinazolinones were obtained in high yields with good to excellent enantioselectivities under mild condition. Furthermore, we disclosed a method for atroposelective synthesis of alkyl-substituted arylquinazolinones involving Brønsted acid-catalysed carbon-carbon bond cleavage strategy. Finally, the asymmetric total synthesis of eupolyphagin bearing a cyclic arylquinazolinone skeleton was accomplished with an overall yield of 32% in six steps by utilizing the aforementioned methodology.

[Effect of rat intestinal flora in vitro on metabolites of acteoside].

Acteoside was used for anaerobic incubation with rat intestinal flora in vitro. HPLC was used to detect the changes of acteoside at different incubation time points and HPLC-Q-TOF-MS was used to identify the metabolites of acteoside. The results showed that acteoside could be metabolized by rat intestinal flora in vitro and the metabolites were 3,4-dihydroxyphenyl acid, caffeic acid and 3-(3'-hydroxyphenyl) propionic acid.

[Quality evaluation of domestic Echinacea extracts].

OBJECTIVE: To determine the content of polyphenol contained samples, in order to provide basis for comprehensive quality evaluation on Echinacea extracts. METHOD: LC-MS was used for qualitative analysis on relevant compounds of the samples of Echinacea extracts. Optimized USP methods, RP-HPLC and QAMS (quantitative analysis of multi-components by single-marker) were used to determine the content of polyphenol. Meanwhile, UV method was adopted for comparative analysis on content according to international standard IS014502-1-2005. RESULT: The six batches of samples could not meet the export standard for polyphenol content by HPLC. UV showed four batches in line with the standard and two batches in inconformity. CONCLUSION: UV method is generally adoptedfor the content determination of domestic Echinacea extracts, but shows results that are significantly different from that by HPLC method. it is suggested to use HPLC method to standardize quality of extracts and raise market access standards.

[Significance of combining tests of thyroid autoantibodies in differential diagnosis between Graves's disease and Hashimoto's hyperthyroidism].

OBJECTIVE: To investigate the differential diagnosis between Graves's disease and Hashimoto's hyperthyroidism to improve positive diagnostic rate in Hashimoto's hyperthyroidism, to facilitate proper management. METHODS: Cytological examination was conducted by fine needle biopsy (FNB) on the thyroids of patients with hyperthyroidism diagnosed by clinical data, including 22 cases of Hashimoto's hyperthyroidism, 5 males and 17 females, aged 39 +/- 12, and 49 cases of Graves's disease, 20 males and 29 females, aged 41 +/- 11. Thyroid auto-antibodies-thyroid peroxidase antibody (TPOAb), thyroid microsomal antibody (TMA), thyroglobulin antibody (TGA), thyroid-stimulating hormone receptor antibody (TRAb), and free serum triiodothyronine (FT3), free thyroxin (FT4), and serum thyroid-stimulating hormone (S-TSH) were tested. The correlation between the pathology of thyroid and different autoantibodies and thyroid hormone was analyzed. RESULTS: TRAb was 42.28 +/- 75.89 in Graves disease group, significantly higher than that in Hashimoto's hyperthyroidism group (5.77 +/- 12.69, P < 0.001). FT3 was 16.13 +/- 9.95, significantly higher than that in Hashimoto's hyperthyroidism group (9.54 +/- 6.76, P < 0.01). In Graves's disease group the positive rates for TRAb, TPOAb, TMA, and TGA were 83.67%, 75.51%, 57.14% and 48.98% respectively. In Hashimoto's hyperthyroidism group, the positive rate for TRAb was 13.64%, and the positive rates for the rest autoantibodies were all 86.36%. The double positive rate of TPOAb and TGA was 86.36% in Hashimoto's hyperthyroidism group, significantly higher than that in Graves's disease group (48.98%). There was a positive association between TRAb and FT3, and between diffuse and symmetric increased size of thyroid and FT3 TRAb. CONCLUSION: Comprehensive analysis of TRAb, TPOAb, TGA, and FT3 is helpful to the differential diagnosis between Graves's disease and Hashimoto's hyperthyroidism.