The fermentation conditions which affect C-15? hydroxylation o f 18-methyl-estr- 4-ene-3,17-dione were investigated. As the key step in the Hydroxylation, the dissolution of substrate was focused on. Tween80, MeOH, DMSO,?-CD and 2-HP?CD were studied to improve the dissolvability of 18-met hyl-estr-4-ene-3,17-dione.The other factors such as pH, substrate concent ration and aeration strategies which affected conversion rate were also resea rched. As a result, the conversion rate can be up to 60% in shake flask and ach i(eve 50% in fermentor,which would overcome the disadvantage of 15?-hydroxyl -18-methyl-estr-4-ene-3,17-dione chemosynthesis and provide a good techn ics to industry.

The regulatory region and the signal peptide sequence of the sacB gene has been amplified by PCR using Bacillus subtilis chromosomal DNA as template, and an inducible secretion vector has been developed based on this sequence, which was ligated with Bacillus subtilis alkaline proteinase gene. Transform Bacillus subtilis DB403 with this vector, and the expression of the inserted Bacillus subtilis alkaline proteinase gene can be induced by addition of sucrose into the medium.

The degQ gene, amplified from Bacillus subtilis by PCR, was cloned to pUBS (sucrose induced secretion vector). After transformed into DB403, recombination named DB403(pUBSD) was formed. The results of the fermentation showed that degQ gene enhanced the expression of B. subtilis fibrin enzyme. The activity of the enzyme was increased to 2.2 times as the original one. In this article, the effects of different conditions, such as different kinds of sugar, different concentration of sucrose and different induced time were also be investigated and compared.

The synthesized full-length hGLP-1 gene was cloned into pET-32a(+) to get the recombinant plasmid pET32-GLP-1, which could express a fusion protein containing thioredox, hexahistidine, and rhGLP-1 consecutively. The recombinant plasmid containing hGLP-1 was transformed into E.coli BL21 (DE3) and expressed by IPTG induction. The fusion protein was purified from lysates with Ni?IDA His?Bind affinity chromatography. rhGLP-1 with the purity of 90% was achieved after enterokinase digestion, Ni?IDA His?Bind affinity chromatography again, then was concentrated by ultrafiltration. The purified rhGLP-1 showed a single band on IEF gel with an isoelectric point between pH5.2 and pH5.85. ESI mass spectrometry showed that the molecular weight was 3355.0kDa as expected. rhGLP-1 was digested with trypsin followed by mass analysis and the peptide mapping produced two expected fragments with the molecular weights of 2097.7kDa and 1005.5kDa, respectively. The purified rhGLP-1 also showed obvious biological activity for both lowering plasma glucose and stimulating insulin secretion in mice.

Objective To determine whether the susceptibility to ischemia-reperfusion injury in aged heart is higher than that in adult heart and,if so,to clarify the mechanisms underlying this change.Methods Wister rats(5-or 20-month-old)were randomly divided into 4 groups(6 animals in each group).The rats were subjected to 30 minutes of myocardial ischemia via ligating the left anterior descending coronary artery,followed by 3 hours of reperfusion(Young-MI/R group and Old-MI/R group);A silk suture around the left anterior descending coronary artery was not ligated in young and old rats(Young-sham group and Old-sham group).Myocardial apoptosis was detected by terminal deoxynueleotidyl transferase biotin-d UTP nick end labeling(TUNEL)staining and caspase-3 activity was detected by using a caspase-3 colorimetrie assay.Nitrotyrosine content,a footprint of in vivo ONOO~-formation,and total NO content were determined by ELISA and chemiluminescence method respectively.Results A significantly exacerbated cardiac reperfusion injury was found in Old-MI/R group as evidenced by increased TUNEL positive myocytes[(19.0?2.1)% vs.(14.6?1.7)%],and increased myocardial caspase-3 activity[(436?35)?mool/mg vs.(340?32)?mol/mg] compared with Young-MI/R group(P＜0.05).Aged hearts had a markedly increased basal NOx level compared with young adult hearts.Marked higher myocardial nitrotyrosine content was found in OId-MI/R group[(7.25?0.18)nmol/g]than that in Young-MI/R group[(4.68?0.15)nmol/g] (P＜0.05).Conclusions In aged hearts,high levels of NO might form highly toxie derivant, ONOO~-,and its subsequent nitrified protein.This may attribute to the increased susceptibility of the aged heart to isehemic-reperfusion injury.

Preparation of a poly (gamma-glutamic acid)-cisplatin conjugate was introduced and its in vitro antitumor effect was investigated. Poly (gamma-glutamic acids) was obtained by using fermentation methods. The hydrolyzed small molecular weight of poly (gamma-glutamic acids) was prepared by acid hydrolysis. The interaction between poly (gamma-glutamic acids) -cisplatin conjugate (PGA-CDDP) and DNA was investigated by PCR model. MTT assay was used to investigate the in vitro anticancer activity of the conjugate. Apoptosis assay of the conjugate was investigated by FCM assay and the in vivo toxicity was also proceeded. The results showed that the poly (gamma-glutamic acids) -cisplatin conjugate was obtained successfully and its yield is 10% - 12%. It has obvious antitumor effects on human liver tumor BEL7404 cells, human lung tumor H446 cells and human colon tumor RKO cells. At the same time, it also has apoptosis effects on the three kinds of tumor cell lines. The in vivo toxicity of PGA-CDDP was examined in normal mice and the results showed that the in vivo toxicity of this conjugate was significantly lower than that of free CDDP. In conclusion, the poly (gamma-glutamic acids) -cisplatin conjuate could be used as a potential clinic antitumor drug. The poly (gamma-glutamic acids) obtained by fermentation can be used as a valuable drug carrier system.
Animals ; Antineoplastic Agents ; administration & dosage ; pharmacology ; Apoptosis ; drug effects ; Cell Survival ; drug effects ; Cisplatin ; administration & dosage ; pharmacology ; Drug Carriers ; Female ; Fermentation ; Hydrogen-Ion Concentration ; Male ; Mice ; Polyglutamic Acid ; administration & dosage ; pharmacology

OBJECTIVETo investigate the biomechanical differences between the surgery and adjacent segments of intervertebral discs in the lower lumbar spine, which were implanted with Coflex into the segments of L4, and L5S1, respectively.

METHODSThree finite-element models (the model of the intact lower lumbar sacrum,the L4.5 and L5S1 segments implanted by Coflex) were developed, respectively. According to the spinal three-column loading theory, three models were forced by the physiological loads of upright standing, flexion and extension. The stress of the different areas of the disc annulus, the changes of intervertebral dorsal height and the degree of nucleus pulposus pressure were compared and analyzed.

RESULTSCoflex implanted into the L4.5 and L5S1 segments in compression and extension could both decrease the stress of the posterior area of intervertebral disc in the surgery segment, resist the changes of the intervertebral disc dorsal height and reduce the perssure of nucleus pulposus. Furthermore, the stress of the L5S1 segment decreased when Coflex fixed the L4.5 segment in extension. However, when Coflex fixed the L5S1 segment, the stress of L4.5 segment had no significant changes.

CONCLUSIONCoflex fixing the L4,5 and L5S1 segments can effectively decrease the stress of the surgery segmental discs, respectively. Furthermore, Coflex fixing L4,5 segment may play a biomechanical role in reducing the stress of L5S1 segment.

Adult ; Biomechanical Phenomena ; Finite Element Analysis ; Humans ; Internal Fixators ; Intervertebral Disc ; physiopathology ; surgery ; Lumbar Vertebrae ; surgery ; Male ; Stress, Mechanical

OBJECTIVETo investigate performance of a biotinylated imaging probe 3a for targeted imaging of breast cancer cells.

METHODSUltraviolet absorption spectrum and fluorescence spectrum were employed to analyze the spectral characteristics of 3a. The fluorescence spectrums of 3a treated with different concentrations of glutathione (GSH) were obtained to determine the sensibility of 3a to GSH. Flow cytometry was used to determine the cellular uptake of 3a by MCF-7 cells, MDA-MB-231 cells and Hs 578Bst cells in the presence or absence of biotin, and the imaging performance of 3a in the 3 cell lines was assessed under an inverted fluorescent microscope. The toxicity of 3a to the cells was evaluated using MTT method.

RESULTS3a showed the strongest absorption peak at 510 nm, and its fluorescence emission signal was the strongest at 544 nm. As the concentration of GSH increased (0-6 mmol/L), 3a exhibited an increasing fluorescence signal at 544 nm. The cellular uptake of 3a was markedly higher in MDA-MB-231 cells and MCF-7 cells than in Hs 578Bst cells. The imaging studies showed that 3a had a good breast cancer cell-targeting property and produced clear images under fluorescent microscope. MTT assay demonstrated no obvious toxicity of 3a in Hs 578Bst cells even at the concentration of 20 µmol/L, but MCF-7 cells and MDA-MB-231 cells exposed to 2-20 µmol/L 3a showed a lowered cell viability.

CONCLUSION3a is capable of targeted imaging of breast cancer cells mediated by biotin. 3a at the concentration of 2-20 µmol/L has minimal cytotoxicity to normal breast cells but can lower the viability of breast cancer cells.

Human glutamate decarboxylase 65(hGAD65) is an enzyme that catalyzes the transformation of L-glutamic acid into ?-aminobutyric acid.It has been found that Type 1 diabetes mellitus(T1DM)is an autoimmune disease,in which pancreatic islet ?-cells are destroyed due to immune response mediated by autoantigen.hGAD65 is considered as a key autoantigen of the autoimmune response,so anti-hGAD65 antibody(hGAD65-Ab) is the most effective and specific immune marker for T1DM diagnosis,and hGAD65 can be used to detect hGAD65-Ab in serum of T1DM patients.The hGAD65 gene was cloned into pET32a(+),then the recombinant plasmid with hGAD65 was transformed into E.coli BL21(DE3) and expressed by IPTG induction.The fusion protein containing thioredox,hexahistidine and hGAD65(Trx-hGAD65) was mostly insoluble,but the band of soluble Trx-hGAD65 could also be detected by SDS-PAGE,and it was a great improvement compared with the results reported.Trx-hGAD65 was isolated from lysate and purified by immobilized metal ion affinity chromatography(IMAC).After enterokinase digestion and IMAC purification,hGAD65 with high purity was obtained.Detection of thin-layer chromatography(TLC) showed that both Trx-hGAD65 and hGAD65 had enzymatic activity,whereas Trx-hGAD65 had better stability.Furthermore,it was confirmed that Trx-hGAD65 was able to conjugate with hGAD65-Ab in the serum of T1DM patients by ELISA assay.In conclusion,Trx-hGAD65 instead of hGAD65 can be used for T1DM diagnosis,and its application in prophylaxis and therapy of T1DM is expectable.

Prawn white spot syndrome is caused by the pathogen prawn white spot syndrome virus (WSSV). VP19 is a vesicle membrane protein of WSSV. HyNPV (Hybrid of AcNPV and BmNPV) constructed by the recombination of BmNPV and AcNPV is a new hybrid virus having both of their advantages. The recombinant transfer vector pBlueBicHisC-vp19 and recombinant baculovirus HyNPV-VP19 were constructed on the basis of the successful cloning of VP19. Newly-molted silkworms Bombyx mori of fifth instar were inoculated by the recombinant virus. SDS-PAGE and Western blotting analysis showed a specific band, about 21kD, which was consistent with the expectation suggesting that the WSSV-VP19 gene was successfully expressed in silkworm bodies.
Animals ; Baculoviridae ; genetics ; metabolism ; Bombyx ; genetics ; metabolism ; virology ; Genetic Vectors ; Penaeidae ; virology ; Recombinant Fusion Proteins ; genetics ; Viral Envelope Proteins ; genetics ; metabolism ; Virus Replication ; White spot syndrome virus 1 ; genetics