[Sample pretreatment methods of pesticide residues in Panax notoginseng of Chinese traditional medicine].

Two sample pretreatment methods of pesticide residues in Panax notoginseng of Chinese traditional medicine were developed. For Method I, the residues were extracted from homogenized tissue with n-hexane-dichloromethane (6:4) by means of ultrasonication, the crude extract was purified by an Envi-carb/NH2 solid-phase extraction (SPE) column. For Method II, matrix solid-phase dispersion (MSPD) technique was used for extracting and cleaning up. The eluates were concentrated by rotary evaporation, and then were redissolved in dichloromethane prior to GC-MS determination. The determination was performed in selected ion monitoring (SIM) mode with the external calibration for quantitative analysis. Under the optimal conditions, the results indicated that the methods are easier and faster, the recoveries of method I for the spiked standards at concentration of 0.01, 0.5, and 2.0 mg x kg(-1) were 81.90%-102.10% with the relative standard deviations (RSDs) of 3.60%-7.10%. The recoveries of method II were 96.26%-104.20% with the RSDs of 3.52%-7.94%. The detection limits (S/N) for residues of pesticides were in the range of 0.48-1.34 ng x g(-1). The results indicated that these multiresidue analysis methods can meet the requirements for determination of residue pesticides and can be appropriate for trace analysis of residue pesticides in Panax notoginseng.

Two GH3 genes from longan are differentially regulated during fruit growth and development.

In the present work, two full length cDNAs of GH3 genes, named DlGH3.1 and DlGH3.2 were cloned from pericarp and aril tissues of the longan fruit, respectively. Three conserved motifs, SSGTSAGERK, YASSE and YRVGD, as a characteristic of the acyladenylate/thioester forming enzyme superfamily were observed in DlGH3.1 and DlGH3.2 proteins. DlGH3.1 mainly expressed in pericarp tissues while DlGH3.2 accumulated in both the pericarp and aril tissues during fruit growth and development. In addition, NAA treatment induced the expression of DlGH3.1 and DlGH3.2 in the pericarp tissues at 21 and 77days after anthesis (DAA), while only DlGH3.2 in the aril tissues could be induced by NAA at 77DAA. More importantly, ABA and ethrel treatments suppressed the accumulations of DlGH3.1 and DlGH3.2 in the pericarp tissues of longan fruit at 21DAA (a rapid growth stage of pericarp), but enhanced DlGH3.2 expression in the aril tissues at 77DAA (a fruit ripening stage). Furthermore, the expression patterns of DlGH3.1 and DlGH3.2 showed different tissue specificity. Thus, our results suggest that DlGH3.1 gene expression might be associated with pericarp growth, while DlGH3.2 accumulation is likely to be related to both pericarp growth and fruit ripening, and the responses of DlGH3s to plant growth hormones are different and dependent on fruit development stage and fruit tissue.

[Effects of pretreatment regimen on mice liver injury in hematopoietic stem cell transplantation].

OBJECTIVE: To investigate the effects of conditioning regimen on mice liver injury during hematopoietic stem cell transplantation. METHODS: Forty healthy 8-10 weeks old female BALB/c mice were randomly divided into control group, non-myeloablative total body irradiation group, myeloablative total body irradiation group, busulfan group and cyclophosphamide group with 8 mice each. The general condition of each mouse was continuously observed. Peripheral white blood cells were counted and pathological changes of liver were examined by hematoxylin and eosin stain under microscope. The ultrastructure changes of hepatocyte and liver vascular endothelium were detected under transmission electron microscope. RESULTS: Compared to control group, each experimental group showed that the count of white blood cells was decreased significantly after conditioning pretreatments (P < 0.05). The conditioning regimen had injury effects on the mice liver in each experimental group. There were various degrees of damage to the hepatocyte and liver vascular endothelium. CONCLUSION: Total body irradiation, Busulfan and Cyclophosphamide all led to the damage of liver vascular endothelium in hematopoietic stem cell transplantation, and may be the important triggers of hepatic veno-occlusive disease.