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.

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.

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

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

ObjectiveTo investigate the effect of ulinastatin on perioperative renal function in patients undergoing orthotopic liver transplantation.MethodsSixty ASA Ⅱ or Ⅲ patients of both sexes aged 35-64 yr weighing 50-75 kg with normal blood urea nitrogen (BUN) and creatinine (Cr) before operation undergoing orthotopic liver transplantation were randomly divided into 2 groups ( n ＝ 30 each):control group (group C) and ulinastatin group ( group U).Anesthesia was induced with midazolam,fentanyl,etomidate and vecuronium and maintained with isoflurane inhalation,propofol TCI,continuous remifentanil infusion and intermittent iv boluses of fentanyl and vecuronium.The patients were tracheally intubated and mechanically ventilated.PET CO2 was maintained at 30-35 mm Hg.Ulinastatin 400 000 IU in normal saline 20 ml was infused iv after induction of anesthesia.Ulinastatin 200 000 IU was then infused every 4 h until 48 h after operation.Urine volume and the amount of furosemide administered were recorded before anhepatic phase,and during anhepatic and neohepatic phase.Venous blood samples and urine were collected before induction of anesthesia (T1),at 15 min of anhepatic phase ( T2 ),at 15min of neohepatic phase (T3),at the end of operation (T4) and 48 h after operation (T5) for determination of serum concentrations of BUN,Cr and creatinine clearance rate and urinary N-acetyl-beta-D-glucosaminidase (NAG)activity and microalbumin concentration.ResultsCompared with group C,ulinastatin significantly decreased the amount of furosemide administered and increased urine volume during anhepatic and neohepatic phase,decreased serum Cr concentration,increased creatinine clearance rate at T2.5,decreased urinary NAG activity and microalbumin concentration at T4.5 and serum BUN concentration at T3-s.ConclusionUlinastatin has protective effect on rehal function during perioperative period in patients undergoing orthotopic liver transplantation.

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.

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 analyze the biomechanical stress distribution on the sagittal fractured of the mandibular condyle(SFMC) fixed by double plates in 3 different ways.Methods:The fixation finite element models with double straight plates(SS),one straight and one L-form plates(SL),and double L-form plates(LL)were established.The biomechanical stresses on condyle were calculated with finite element analysis.Results:In the model of SS fixation the maximum equivalent stress (MES),maximum total displacement (MTD)and maximum total corner(MTC)of condylar stump were 525.475 MPa,0.902 2 mm and 0.260 1°;MES,MTD,and MTC on fractured free-end were 4.425 MPa,0.882 7 mm and 0.019 9°,respectively.In the model of SL fixation MES,MTD and MTC on condylar stump were 1 135 MPa,0.9367 mm and 0.126 1°;MES,MTD and MTC on fractured free-end were 2.656 MPa,0.887 1 mm and 0.016 9°,respectively.In the model of LL fixation MES,MTD and MTC on condylar stump were 2 208 MPa,0.923 8 mm and 0.172 2°;MES,MTD and MTC on fractured free-end were 14.66 8 MPa,0.876 6 mm and 0.018 1°,respectively.Conclusion:Double L plates fixation is a proper way for SFMC.

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.