In plant genetic engineering, selectable marker is needed to distinguish transformant. As the commercialization of transgenic plants, people are more and more paying close attention to their safety, among which mainly refers to the safety of selectable marker. In order to increase the safety of transgenic plants, biologists began to search for biosafe selectable marker.Current research progress of taking key enzyme in metabolic pathways were overviewed,which include glycometabolism, amino acid metabolism, hormone metabolism ,nucleotide metabolism and protein metabolism et cetera, as selectable marker in transgenic plants.

The rodipicolinate synthase gene was cloned from Nicotiana tabacum L.cv,which encodes the key enzyme in the synthesis of lysine,and then a vitro molecular reform reliefing feedback suppression was made. Some resistant seedlings were acquired using the mutated gene as selectable marker and analog of lysine as selectable reagent,and the detection results were positive by means of PCR and Real-Time PCR,however the phenotype is somewhat abnormal.

Heart ; drug effects ; Heart Failure ; drug therapy ; Humans ; Hydrogen Bonding ; Nitrogen Oxides ; pharmacology ; therapeutic use

Malignant biliary tract obstruction is a common disease.Nowadays,endoscopic biliary drainage (EBD) and percutaneous transhepatic biliary drainage (PTBD) have been used to treat such disease.EBD is a first-line intervention for lower segment of biliary duct obstruction caused by pancreatic cancer or other tumors.PTBD is a first-line treatment for gallbladder cancer or other tumors which lead to the hilar and intrahepatic bile duct obstruction and abnormal digestive anatomy.In a word,the proper selection of the drainage should be based on the patients' condition with minimal trauma and maximum therapeutic effect.

Raman spectroscopy has generated many branches during the development for more than 90 years. Surface enhanced Raman spectroscopy (SERS) improves SNR by using the interaction between tested materials and the surface of rough metal, as to quickly get higher sensitivity and precision spectroscopy without sample pretreatment. This article describes the characteristic and classification of SERS, and updates the theory and clinical application of SERS. It also summarizes the present status and progress of SERS in various disciplines and illustrates the necessity and urgency of its research, which provides rationale for the application for SERS in microbiology.
Microbiology ; Spectrum Analysis, Raman

AIM:To put forward three-level design(Box-Behnken design)for fitting response surfaces to optimize the extraction technology of total flavonoids from Hypericum ascyron L.METHODS:Four factors,including temperature,reflux time,concentration of ethanol,ratio of solvent to raw material were used to examine the yield of total flavonoids.Prediction was carried out through comparing the observed and predicted values.RESULTS:The results suggested that ethanol concentration and extraction temperature were two statistically significant factors.The optimum conditions of extraction process consisted of the ratio(mL:g)of solvent to material(13.3:1),ethanol concentration(53.2%),extraction temperature(78.7℃)and extraction time(2.3h).Regression coefficient of binomial fitting complex model was as high as 0.984 6.Bias between observed and predicted values was-4.01%.CONCLUSION:Box-Behnken design is success in optimizing the extaction in close agreement with the predicted values of the mathematic model.

Objective To develop a one-step PCR assay for rapid discrimination of six Brucella species and some intraspecific biovars.Methods Using 6 pairs of primers in one-step PCR to differentiate six classical Brucella species and some biovar in ordinary PCR instrument.The tested strains including 27 reference strains of six Brucella species and 239 Brucella strains were estimated by the PCR assay and biological identification methods.Results The six Brucella species could be precisely differentiated by the onestep PCR assay from the tested strains.Five biovars and vaccine strain of B.suis species could be determined,and biovars 1,3,4 and biovars 2,5,6,7,9 of B.abortus species could be identified at the level of their biovar,moreover,biovars 1,2 and 3,and vaccine strain Rev 1 of B.melitensis species were also discriminated at the biovar and strain level.The accurate rates of the biological identification method and the PCR assay were 98.33％ and 100％ respectively.Conclusion One-step PCR assay was a rapid,specific,and low cost method for identification of Brucella species and discriminating biovars in ordinary PCR instrument.

Water soluble extract (WSE) is an important index for the quality evaluation of Astragali Radix (AR). In this study, the WSE of the wild AR from Shanxi province (SX) and the cultivated AR from Gansu Province (GS) were compared. The WSEs of two types of AR were determined according to the appendix of Chinese pharmacopoeia. Then the WSEs were subjected to NMR analysis, and the obtained data were analyzed using HCA, PCA, OPLS-DA, microarray analysis, and Spearman rank analysis. In addition, the Pearson correlation of differential metabolites were also calculated. The results showed that the WSE content of GS-AR (37.80%) was higher than that of SX-AR (32.13%). The main constituent of WSE was sucrose, and other 18 compounds, including amino acids, organic acids, were also detected. Multivariate analysis revealed that SX-AR contained more choline, succinic acid, citric acid, glutamate, taurine and aspartate, while GS samples contained more sucrose, arginine and fumaric acid. In addition, the Pearson correlations between different metabolites of the two types of AR also showed apparent differences. The results suggested that the WSE of two types of AR differs not only in the content, but also in the chemical compositions. Thus, the cultivation way is important to the quality ofAR. This study supplied a new method for the comparison of extract of herbal drugs.

Embryo Transfer ; Endometrium ; Female ; Fertilization in Vitro ; Humans ; Integrative Medicine

Objective To compare the cardiac function parameters in gated SPECT determined by filtered back projection (FBP) and OSEM reconstruction methods. Methods One hundred and forty-four patients underwent 99Tcm-MIBI gated-SPECT imaging studies. The parameters LVEF, EDV and ESV, were derived using quantitative gated SPECT (QGS), four-dimensional model SPECT (4D-MSPECT) and emory cardiac toolbox (ECToolbox) softwares. Each image was reconstructed by FBP or OSEM. Bland-Altman analysis and paired t-test were applied to evaluate those parameters. Results Correlation coefficients for LVEF, EDV and ESV between FBP and OSEM methods were all more than 0.93 (all P<0.001). EDV calculated by FBP was lower than that by OSEM using QGS software, but became the opposite when using 4D-MSPECT and ECToolbox softwares. (QGS: (82.2±39.1) ml vs (83.5±40.8) ml, t=-2.53, P<0.05; 4D-MSPECT: (93.5±46.9) ml vs (88.8±45.2) ml, t=5.95, P<0.01; ECToolbox: (106.4±51.1) ml vs (100.8±49.0) ml, t=3.99, P<0.01). ESV calculated by FBP was higher than that by OSEM using 4D-MSPECT software (4D-MSPECT:(37.5±41.4) ml vs (34.8±37.6) ml, t=3.92, P<0.01). LVEF calculated by FBP was lower than that by OSEM using QGS software ((62.1±16.9)% vs (63.1±16.1)%, t=-3.14, P<0.05), but higher than that by OSEM using ECToolbox software ((74.1±18.8)% vs (71.3±17.1)%, t=5.28, P<0.01). Conclusion Generally, cardiac functional parameters based on FBP and OSEM construction methods correlated well, although they might have singnificantly different results.