[Objective] To measure the nitrogen content in Agrocybe cylindracea R.Maire,compare the advantages of Kai's Nitrogen-testing method and Spectrophotometric method.[Method]Take Kai's Nitrogen-testing method and Spectrophotometric method.[Result]The two methods were almost the same in the measurement of nitrogen,i.e.30.70mg/g,which had no marked difference by t test.[Conclusion]Spectrophotometric method is simple and convenient for operation,quickly and correctly,and can be used for measurement of total nitrogen.

Although heterologous biosynthesis of polyketide erythromycin has been successfully achieved in Escherichia coli, the titer remains at a very low level (-10 mg/L). In this study, based on genome-scale metabolic model of E. coli, in silico method flux distribution comparison analysis was used to discover novel potential targets for heterologous 6-dEB biosynthesis. Synthetic small regulatory RNAs (sRNAs) was used to experimentally test 12 down-regulated targets. The results showed that repression of each of these target genes e.g. lsrC and ackA led to significantly improve heterologous 6-dEB biosynthesis. Using co-repression of lsrC and ackA, 6-dEB titer was improved by 59.9% in shake-flask with a maximum yield of 22.8 mg/L. This study indicates that combined flux distribution comparison analysis and synthetic small regulatory RNAs is an effective strategy to improve 6-dEB production in E. coli.
Down-Regulation ; Erythromycin ; biosynthesis ; Escherichia coli ; genetics ; metabolism ; Industrial Microbiology ; methods ; RNA

Epidermalgrowthfactorreceptor-tyrosinekinaseinhibitor(EGFR-TKI)resistanceinnon-small cell lung cancer(NSCLC)has become more and more common,which includes primary and secondary resistance.The primary resistance is mainly related with EGFR gene mutation,and the secondary resistant is mainly related with T790M,MET and other genes.

The pathway of 2-methyl-D-erythritol-4-phosphate (MEP) is the exclusive isoprenoid precursor biosynthetic pathway in Escherichia coli, with a higher theoretical yield than mevalonate (MVA) pathway. However, due to lack of information about the regulation of MEP pathway, only engineering MEP pathway in E. coli achieved limited improvement of heterologous isoprenoid production. We used exogenous MEP pathway genes to improve MEP pathway in E. coli and optimized the glucose feeding to release the potential of MEP pathway. The results demonstrate that co-expression of dxs2 from Streptomyces avermitilis and idi from Bacillus subtilis can increase amorphadiene production with 12.2-fold compared with the wild-type strain in shake flask fermentation. Then we established a high-cell density fermentation process for the engineered strain, and found that the phase from 24 to 72 h is important for product biosynthesis. The optimization of glucose feeding rate during 24 to 72 h significantly improved product accumulation, which was improved from 2.5 to 4.85 g/L, within the same process time. Considering the attenuation of strain metabolism after 72 h, this study further modulated the glucose feeding rate during exponential phase to control strain growth and the amorphadiene yield eventually reached to 6.1 g/L. These results provided useful information to develop engineered E. coli for isoprenoid production through MEP pathway engineering.
Bacillus subtilis ; Biosynthetic Pathways ; Culture Media ; chemistry ; Erythritol ; analogs & derivatives ; metabolism ; Escherichia coli ; genetics ; metabolism ; Genetic Engineering ; Glucose ; chemistry ; Industrial Microbiology ; Sesquiterpenes ; metabolism ; Sugar Phosphates ; metabolism ; Terpenes ; metabolism

AIM:To investigate the changes of apelin in blood and myocardium, and the protective mechanisms of ganoderma spores on myocardial ischemia injury induced by isoproterenol in rats. METHODS: The model of myocardial ischemia injury was induced by subcutaneous injection of high dose isoproterenol. Enzyme linked immunosorbent assay (ELISA) was used to measure the apelin contents in blood and myocardium. Semi-quantitative RT-PCR was used to measure the apelin mRNA level in myocardium. Electron microscope was used to observe the pathomorphological changes of myocardium. Ganoderma spores was administered i.g. for 7 weeks. RESULTS: Compared with the normal control group, the apelin contents in blood and myocardium and the apelin mRNA level in myocardium were significantly decreased in the model group (P

OBJECTIVE: To explore whether pre-administration of Ganoderma lucidum spore (GASP) can reduce incidence of neural tube defects (NTDs) induced by all-trans retinoic acid (ATRA) in pregnant mice. METHODS: Twenty pregnant mice were randomly divided into four groups: normal control group, solvent-treated group, ATRA-induced group, and GASP-treated plus ATRA-induced group. GASP solution, which was prepared with solvent (sodium carboxymethyl cellulose), was fed to the pregnant mice in the GASP-treated plus ATRA-induced group twice a day from embryo (E) 0 d to E10.5 d. The same dose of solvent was given to the pregnant mice in the solvent-treated group. At E7.75 d, ATRA (50 mg/kg) was given to the pregnant mice in both ATRA-induced group and GASP-treated plus ATRA-induced group for single time. Embryos were sampled from pregnant mice at E10.5 d. Then the incidence rate of NTDs in mouse embryo was calculated and the crown-rump length of mouse embryo was measured. The positive rate of nestin expression and the distribution of cell cycle of embryonic neural tube neuroepithelial cells were detected by histochemical staining technique and flow cytometry respectively. Reverse transcription-polymerase chain reaction method was used to detect the gene expressions of cyclin-dependent protein kinase 2 (Cdk2) and Cdk4 mRNAs. RESULTS: The incidence rates of NTDs in mouse embryos in the ATRA-induced group and the GASP-treated plus ATRA-induced group were 79.41% and 21.67% respectively, while the crown-rump length of mouse embryos in these two groups were (3.62+/-1.27) mm and (5.84+/-0.92) mm respectively. The positive rate of nestin expression in embryonic neural tube neuroepithelial cells of mouse embryo at E10.5 d in the ATRA-induced group was 32.44%, while that in the GASP-treated plus ATRA-induced group was 77.65%. The cell cycle of embryonic neural tube neuroepithelial cells was obviously arrested at G(0)/G(1) phase in the ATRA-induced group as compared with that in the GASP-treated plus ATRA-induced group. The Cdk4 mRNA was transcripted at a high level in embryonic neural tube in the GASP-treated plus ATRA-induced group, but the Cdk2 mRNA was not detected in this group. CONCLUSION: Pre-administration of GASP can reduce the incidence of NTDs induced by ATRA in pregnant mice.

Objective To investigate the relationship between the polymorphism of transforming growth factor-β1 (TGF-β1 ) gene and risk of chronic hepatitis B virus(HBV)infection progressing to hepatocellular carcinoma(HCC).Methods 120 patients with chronic HBV infection(case group)and 100 age-and sex-matched healthy individuals(healthy control group)were randomly enrolled to this study.The polymerase chain reaction-restriction fragment length polymorphism technique was adopted to detect the single nucleotide polymorphism of TGF-β1 gene(T29C),and made the comparative analysis combined with TGF-β1 mRNA level. Results The risk of HCC occurrence in the patients carrying genotype CC was decreased than that in the patients carrying geno-type TT (OR=0.317,95%CI =0.110-0.913,P =0.033;OR=284,95%CI =0.093 -0.866,P =0.027),the risk of HCC in pa-tients carrying allele C was significantly decreased compared with that in the patients carrying allele T(OR =0.570,95%CI =0.341 -0.953,P =0.032;OR=0.548,95%CI =0.320-0.936,P =0.028).In the HCC group,the patients carrying genotype CC had the lower lever of TGF-β1 mRNA.Conclusion TGF-β1 gene polymorphism(T29C)may be related to the risk of chronic HBV infection progressing to HCC.

OBJECTIVE: To standardize and simplify the drug receving and preparing model. METHODS: Reasonable pharamcy inventory parameters were set up based on our experience; second order drug storeroom dynamic inventory system was designed and applied, and the indexes of drug storeroom inventory and workload of the new and the old models were reported and analyzed. RESULTS: The new warning system provided an optimal inventory, and in which the incidences of overstock or stock shortage, the frequency of daily drug receving, drug kinds and the time used with checking stock and filling receipt were all significantly less than in the traditional model. CONCLUSION: Due to the second order drug storeroom dynamic inventory warning system, the drug receiving was more scientific, the drug stock amount was reduced and the drug receiving time was saved, and the mangament level of hospital drug storeroom inventory was enhanced.

Objective To evaluate the imaging performance and characteristics of peripheral primitive neuroectodermal tumors (pPNET), in order to raise awareness of the disease and the diagnostic accuracy. Methods Thirteen patients with pPNET who confirmed by puncture or pathology were enrolled in this study. The CT and MRI features were retrospectively analyzed. Four patients received simple routine CT examination, and 9 patients had MRI examination based on X-ray, CT examination. Results The part of body involved was more widely.Two patients occurred in the sinuses, 1 patient in the chest wall, 1 patient in the lung, and 3 patients in the abdominal and pelvic(1 patient involved the pelvic floor through the pelvic wall lesions to basins), 1 patient in the spine, and 5 patients located in the extremities. The characteristics of pPNET by CT and MRI in soft tissue of 8 patients showed single large soft tissue mass, and the biggest was 11.2 cm × 10.6 cm. In bonds and joints of 5 patients, CT and MRI showed wide range of soft tissue mass, mixed internal signal/density with obviously uneven enhancement, significant bone destruction and dissolvable osseous changes, and no obvious tumor bone and calcification. Conclusions Each site has its relative imaging characteristics of pPNET. CT and MRI can show lesions involving the scope, internal structure, with or without adjacent tissue invasion and metastasis, and provide guidance for clinical treatment and selecting treatment regimen. But in the end, it depends on the diagnosis of pathological and immunohistochemical examination.

OBJECTIVE: To investigate the effects of Ganoderma spores on mitochondria-related molecular substances in hippocampus of young rats birthed by rats with gestational hypertension. METHODS: Nitric oxide synthase (NOS) inhibitor Nw-nitro-L-arginine methylester (L-NAME) was intraperitoneally injected into pregnant rats to induce gestational hypertension, and Ganoderma spores were administered orally. The effects of Ganoderma spores on levels of mitochondria-related molecular substances in hippocampus of young rats birthed by the rats with gestational hypertension were evaluated with immunoradiometric assay of cAMP, RT-PCR analysis of related genes, and detection of enzyme activity. RESULTS: In hippocampus of the new-born rats birthed by rats with gestational hypertension, the cAMP level, mitochondrial DNA (mtDNA) level and adenosine triphosphatase (ATPase) activity were decreased, and the expression level of peroxisome proliferator activated receptor gamma coactivator 1 alpha (pgc1 alpha) was unchanged compared to the normal control group. The cAMP level, mtDNA level, ATPase activity and pgc1 alpha expression level in hippocampus of 30-day post-natal rats were lower than those of the rats in normal control group. After oral administration of Ganoderma spores, the cAMP and mtDNA levels in hippocampus of the new-born rats and 30-day post-natal rats recovered almost to the levels of normal control rats, and the ATPase activity and pgc1 alpha expression level were also increased significantly. CONCLUSION: Ganoderma spores may regulate the levels of mitochondria-related molecular substances in hippocampus of young rats birthed by rats with gestational hypertension.