Delightful achievements have been obtained in forestry genetic breeding since the application of transgenic technology in this field during the past 20 years. Field trials of some genetic modified (GM) trees have been carried out, and some GM trees have been commercialized. Meanwhile, the risks of ecological safety caused by GM trees have raised attention in the public gradually. These issues mainly include the horizontal transfer and vertical flow of foreign genes, and the potential effects on insects, soil ecosystems and virus. The current status of field trials, commercial applications and the potential ecological risks of GM trees were summarized. Then the prospects of GM trees were also presented.

Objective To study the correlation between drug-resistance of paclitaxel and the expres- sion levels of anti-apoptotic protein survivin and the role of matrine reversal resistance of PTX in non-small cell lung cancer.Methods The expressions of survivin in 120 samples of human lung cancer with paclitaxel chemotherapy were detected by immunohistochemical staining.Results The positive expression rate of sur- vivin was 57.5%.In the positive expression of survivin group,chemotherapy combined matrine could improve response rate and survival time(P0.05).Conclusion The survivin expression was related to the response rate of paclitaxel in lung cancer.It might be a valuable new marker to predict the drug-resistance of paclitaxel.In this prospective research,survivin protein,which promoted the apoptosis caused by paclitaxel,may be the target of martine.It could partly reverse the drug re- sistance to paclitaxel.

Objective To investigate the effect of high power microwave(HPM) irradiation on neuropeptide Y (NPY) and neural nitric oxide synthase (nNOS) expression in the cerebral cortex and hippoeampus of Wistar rats. Methods A total of 110 Wistar rats were used for this study.Three groups of 30 Wistar rats were exposed to HPM irradiation at intensities of 3,10,30 and 100 mW/cm~2,respectively.Twenty rats served as controls and were ex- posed to sham HPM irradiation.At 6 h,and at 1,3,7,14 and 28 d after irradiation,five rats from each group were sacrificed,and their cerebral cortices and hippocampi were harvested.HE staining was used to highlight any change in the structure of the cerebral cortex or hippocampus.Immunohistochemistry techniques and image analysis were used to study the changes in NPY and nNOS expression.Results 10 to 100 mW/cm~2 HPM irradiation caused pyc- nosis and deep staining of some neurons in the cerebral cortex and hippocampus.The increase in nNOS expression and decrease in NPY expression observed were significant at 3 days after irradiation.Conclusion HPM irradiation can induce injury in neurons of the cerebral cortex and hippoeampus,and abnormal NPY and nNOS expression.

Based on the genomic information of Emericella sp. 1454, in conjunction with literature analysis of its secondary metabolite emestrin, this study identified the biosynthetic precursors of emestrin and enhanced its production by supplementing the culture medium with these precursors. In this study, it was found for the first time that the addition of biosynthetic precursor, reduced glutathione, to the culture medium significantly increased emestrin yield. By incorporating 1.5 g of reduced glutathione into 50 g of rice culture medium and fermenting for 15 days, a yield of 30.82 mg of emestrin was obtained, which marked an 11.71-fold increase compared to the original fermentation approach. The method is both simple and cost-effective, establishing a solid foundation for the efficient synthesis of emestrin and similar compounds. Additionally, it serves as an important reference for enhancing the production of other epipolythiodioxopiperazine compounds.

Objective To investigate the effects of CD137-CD137L interaction on the nuclear factor of activated T cells c1 (NFATc1) in apolipoprotein E knockout (ApoE-/-) mice.Methods Atherosclerotic plaque model was produced by rapid perivascular carotid collar placement in ApoE-/- mice.In vivo,the expression of NFATc1 in mice plaque and lymphocytes was detected by immunohistochemical and flow cytometry, respectively.In vitro, the NFATc1 mRNA and protein expressions in cultured lymphocytes of ApoE -/- mice were measured by RT-PCR and flow cytometry,respectively.Results In vivo,after stimulating CD137-CD137L signal pathway, the expression of NFATc1 was significantly upregulated in the atherosclerotic plaques and lymphocytes.In vitro,the mRNA and protein expressions of NFATc1 in cultured leukocytes of ApoE-/- mice were also significantly increased,the maximal effect appeared post 20 μg/ml anti-CD137 mAb- stimulation and reached maximum at 24 h at any concentrations.Anti-CD137L mAb significantly downregulated the mRNA and protein expressions of NFATcl in lymphocytes of ApoE -/- mice,maximal effect appeared at 20 μg/ml anti-CD137L mAb and reached minimum at 24 h.Conclusion CD137-CD137L interactions can modulate the expression of NFATc1 in this ApoE -/- mice atherosclerotic plaque model.

OBJECTIVETo establish a method for the determination of theacrine in rat plasma after ig. administration of theacrine.

METHODBlood sample was taken timely from the eyes canthus of rats. Plasma was isolated and the protein was precipitated by ethyl acetate. Then the plasma concentration of theacrine was determined with RP-HPLC. Caffeine was used as the internal standard. The chromatographic conditions were as follows: Phenomenex Luna C18 (4.6 mm x 250 mm, 5 microm) at 25 degrees C, a mixture of methanol-water (25: 75) as the mobile phase, at the flow rate of 1.0 mL x min(-1) and the detection wavelength of 290 nm.

RESULTThe linear range of theacrine was 0.5-100 mg x L(-1) (R2 = 0.998 9). The lower limit of quantification was 0.5 mg x L(-1). The intra-day RSD was 1.49% 4.40% and inter-day RSD was 0.80% -10.27%. The average extraction recoveries of theacrine were 90.3% -95.8% at concentrations of 0.5, 5.0, 50 mg x L(-1). The main pharmacokinetic parameters after ig. administration of theacrine at concentration of 30 mg x kg(-1) were as follow: C(max) (35.45 +/- 30 2.68) mg x L(-1), t(max) (0.51 +/- 0.13) h, t1/2 (3.13 +/- 1.37) h, AUC(0-infinity) (2.65.39 +/- 94.71) mg x L(-1) x h.

CONCLUSIONThe method has been confirmed to be simple, stable, reproducible and with high specificity, and can be used for the pharmacokinetic study of theacrine in rats.

Animals ; Blood Chemical Analysis ; methods ; Calibration ; Chromatography, High Pressure Liquid ; methods ; Chromatography, Reverse-Phase ; methods ; Rats ; Rats, Sprague-Dawley ; Reproducibility of Results ; Uric Acid ; analogs & derivatives ; blood ; pharmacokinetics

Objective To develop a eoexpression plasmid which expressing envelope protein and nucleoprotein of hepatitis B virus and know of its expressing efficiency. Methods The plasmid coexpressing envelope protein and nucleoprotein of hepatitis B virus under the CMV promoter respectively was constructed by gene recombination. Cellular expression was assessed by ELISA. Results Multiple cloning site was inserted into expression vector contain hepatitis B virus PreS2-S gene. And expression unit containing hepatitis B virus PreC-C was cloned into it. HBsAg and HBeAg was detected both in the culture supernatant and in the cells. Conclusion The coexpressing plasmid was constructed successfully and it can express effectively in vitro. This has provided a basis for further research of the therapeutic HBV DNA vaccine.

OBJECTIVETo explore the feasibility of a dual-energy computed tomographic angiography (DECTA) protocol using test-bolus injection with reduction of contrast material (CM) dose in second generation dual-source CT system.

METHODSTotally 57 consecutive patients underwent CT angiography scan covering the cervical and cerebral arteries. CT was performed with second generation dual-source CT system. The time to peak (T) using a test-bolus injection was calculated. The patients were divided into three groups (A, B, and C) with different CM doses (40, 45, and 50 ml) and different delay time points [ (T+1) , (T+1) , and (T+2) s] . All the patients were followed by a 48 ml saline flush. Arterial enhancements were quantified by measuring attenuation values of the aortic arch, bifurcation of common carotid artery, contralateral internal jugular vein of the CM injection, superior vein cava, proximal middle cerebral artery, basilar artery, and straight sinus on source images. Visualizations of intracranial artery and ipsilateral venous effect of the CM injection were rated on a four-point grading scale on CTA images for qualitative assessment.

RESULTSAlthough the attenuation of internal jugular vein and straight sinus were significantly lower in group A than in groups B and C (P<0.05) , the attenuation of aortic arch, superior vein cava, common carotid artery, middle cerebral artery, and basilar artery vessels showed no significant differences among these three groups. The scores of the visualizations of intracranial artery and ipsilateral venous effect of the CM injection were also not significantly different among these three groups.

CONCLUSIONBased on the delay time calculated by a test-bolus injection, a reduced-dose contrast material may provide an equal degree of arterial attenuation and a lower attenuation of vein for dual-energy CTA covering the craniocervical region in second generation dual-source CT system.

Adult ; Aged ; Angiography ; methods ; Contrast Media ; administration & dosage ; Feasibility Studies ; Female ; Head ; diagnostic imaging ; Humans ; Male ; Middle Aged ; Neck ; diagnostic imaging ; Radiation Dosage ; Tomography, X-Ray Computed ; methods

This study was aimed to investigate the effect of all-trans retinoic acid (ATRA) combined with SBA-Na on the biologic activities of human leukemia K562 and Kasumi-1 cell lines and their mechanism. The ATRA solution of 10(-6) mol/L (W1), 10(-4) mol/L (W2) and the SBA-Na solution of 100 µg/ ml (Z1) and 200 µg/ml (Z2) were prepared respectively. The K562 and Kasumi-1 cells were treated with W1, W2, Z1, Z2, W1 + Z1 and W2 + Z2 respectively, at same time, the blank control was set up. The cell morphology and growth in different treated groups were observed under light microscope. The CCK-8 method was used to detect the proliferation ability of cells, the cell growth curves were drawn, the inhibitory rate of cells was calculated. The flow cytometry with PI single staining and PI/Annexin V double stainings was used to detect the change of cell cycle and apoptosis of 2 cell lines treated with different drugs. The RQ-PCR was used to detect the change of Cyclin A mRNA expression in K562 cells. The results showed both ATRA and SBA-Na displayed inhibitory effect on cell proliferation, and the combination of these two drugs had stronger effect. As compared with the control group, the cell cycle distribution were changed obviously, and the apoptosis increased more significantly in treated groups, especially in group of ATRA combined with SBA-Na. The Cyclin A mRNA expression was up-regulated in Z1 group, while Cyclin A mRNA expression was down-regulated in other groups. It is concluded that both ATRA and SBA-Na can inhibit the proliferation of K562 and Kasumi-1 cell lines and promote their apoptosis. This effect may be stronger when both drugs combined. For K562 cells, the inhibitory effect may be accomplished through down-regulation of Cyclin A mRNA.
Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclin A1 ; metabolism ; Deoxycholic Acid ; pharmacology ; therapeutic use ; Humans ; K562 Cells ; Tretinoin ; pharmacology ; therapeutic use

OBJECTIVETo investigate the effect of 5-Aza-2'-deoxycytidine (5-Aza-dC) on TIP30 gene expression and the relationship between TIP30 expression and the sensitivity to 5-fluouracil (5-Fu) in colorectal cancer cells.

METHODSThe methylation profile of TIP30 gene in HCT116 colorectal cancer cells was determined by methylation-specific PCR. The levels of TIP30 mRNA and protein were determined by RT-PCR and Western blot after the 5-Aza-dC treatment. MTT assay was used to detect the chemosensitivity of HCT116 cells to 5-Fu.

RESULTSTIP30 gene displayed complete DNA methylation in the HCT116 cells without 5-Aza-dC pretreatment. After the 5-Aza-dC treatment for 3 days, only demethylating PCR amplification product was detected and TIP30 gene showed DNA demethylation. With the prolongation of the time of removal of 5-Aza-dC treatment, methylated and demethylated PCR amplification products were observed and TIP30 gene displayed both DNA methylation and DNA demethylation in the colorectal cancer cells. At the day 10 after removal of 5-Aza-dC, methylating PCR amplification product appeared and TIP30 gene showed DNA methylation. No expressions of TIP30 mRNA and protein were detected in the HCT116 cells untreated with 5-Aza-dC. After the treatment of 5-Aza-dC for 3 d and then removed the 5-Aza-dC, the expressions of TIP30 mRNA and protein were increased obviously. With the prolonged time after 5-Aza-dC removal, the expressions of TIP30 mRNA and protein decreased and reached the lowest level on day 10. The IC50 values of 5-Fu were 41.62, 33.17 and 4.96 µg/ml in the HCT116 cells pretreated with 5-Aza-dC, d0 and d10 with the drug removal after drug treatment for 3 d, respectively.

CONCLUSIONSThe results of this study show that the expression of TIP30 gene may be associated with its DNA methylation status and may affect the sensitivity of colorectal cancer cells to 5-Fu.

Acetyltransferases ; genetics ; metabolism ; Antimetabolites, Antineoplastic ; pharmacology ; Azacitidine ; analogs & derivatives ; pharmacology ; Cell Proliferation ; drug effects ; CpG Islands ; genetics ; DNA Methylation ; drug effects ; Drug Resistance, Neoplasm ; drug effects ; Fluorouracil ; pharmacology ; Gene Expression Regulation, Neoplastic ; HCT116 Cells ; Humans ; Inhibitory Concentration 50 ; RNA, Messenger ; metabolism ; Transcription Factors ; genetics ; metabolism