Background and purpose:This study aimed to investigate the effect of glucagon-like peptide-1 receptor agonists on proliferation, secretion of calcitonin and energy metabolism of medullary thyroid cancer (MTC) cell.Methods:The MTC cell line (TT) was culturedin vitro. After treatment with exenatide and liraglutide (0, 1, 10 and 100 nmol/L) for 24, 48 and 72 h, the proliferation of TT was analyzed by CCK-8 kit, the calcitonin was measured by calcitonin assay kits, and the energy metabolism of TT was measured by Seahorse XF instrument.Results:When compared with control group, neither exenatide nor liraglutide had effects on proliferation of TT (P>0.05); the calcitonin levels did not change signiifcantly after treatment with GLP-1 receptor agonists (P>0.05). Exenatide and liraglutide did not alter glycolysis and mitochondrial respiration in TT cells in a dose- and time-dependent manner.Conclusion:GLP-1 receptor agonists have no effect on the development of TT. Further collection of the safety data of exenatide and liraglutide on thyroid is still needed.

Filamentous fungi are widely used in industrial fermentation. Particular fungal morphology acts as a critical index for a successful fermentation. To break the bottleneck of morphological analysis, we have developed a reliable method for fungal morphological analysis. By this method, we can prepare hundreds of pellet samples simultaneously and obtain quantitative morphological information at large scale quickly. This method can largely increase the accuracy and reliability of morphological analysis result. Based on that, the studies of Aspergillus niger morphology under different oxygen supply conditions and shear rate conditions were carried out. As a result, the morphological responding patterns of A. niger morphology to these conditions were quantitatively demonstrated, which laid a solid foundation for the further scale-up.
Aspergillus niger ; cytology ; Fermentation ; Industrial Microbiology ; Reproducibility of Results

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

Objective To investigate the effect of CXCL16 on the development of murine collageninduced arthritis (CIA). Methods CXCL16 mRNA of the involved synovium and serum CXCL16 protein were determined respectively by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme linked immunosorbent assay (ELISA) in murine collagen-induced arthritis. The proliferation of lymphocytes from murine spleen and the level of RANKL mRNA, stimulated by CXCL16 at different concentrations (0,100, 200, 400, 800 ng/ml), was detected respectively by CCK-8 and RT-PCR, then the level of IL-2 and IFN-γ in culture supernatant was detected by ELISA. Comparisons between groups were tested by t test and one-way ANOVA analysis. Results The serum CXCL16 [(127± 10) vs (72±8) pg/ml, P＜0.05] and synovial CXCL16 mRNA (0.214±0.007 vs 0.375±0.009, P＜0.01) in CIA were all significantly higher than those in normal controls. The proliferation of CXCL16 (200, 400, 800 ng/ml) in CIA mouse lymphocytes, was significantly higher than that of CXCL16 (0 ng/ml) (0.51±0.06, 0.56±0.05, 0.55±0.04, (0.41±0.04, P＜0.05). And CXCL16 on the CIA stimulated lymphocyte proliferation was significantly higher than controls on normal lymphocytes (P＜0.05). Compared with blank control group, the expression of IL-2, IFN-γ and RANKL mRNA of CIA CXCL16 (400, 800 ng/ml) groups was higher significantly (P＜0.01). Conclusion CXCL16 plays an important role in the development of murine CIA by activating lymphocytes.

The triple negative breast cancer is one of importance in clinical subtypes of breast cancer, which is easy to recur and metastasis, and its prognosis is very poor.Radiotherapy, as an effective method for breast cancer,can reduce the risk of local recurrence.This article elaborates its characteristics,the progress of ra-diotherapy in the breast conserving surgery and modified radical mastectomy in triple negative breast cancer,when is the appropriate time for radiotherapy and radiotherapy sensitization,and hope that it will be helpful to the treat-ments.

Carbon-limited continuous culture was used to study the relationship between the growth of Aspergillus niger and the production of glucoamylase. The result showed that when the specific growth rate was lower than 0.068 h(-1), the production of glucoamylase was growth-associated, when the specific growth rate was higher than 0.068 h(-1), the production of glucoamylase was not growth-associated. Based on the result of continuous culture, the Monod dynamics model of glucose consumption of A. niger was constructed, Combining Herbert-Pirt equation of glucose and oxygen consumption with Luedeking-Piret equation of enzyme production, the black-box model of Aspergillus niger for enzyme production was established. The exponential fed-batch culture was designed to control the specific growth rate at 0.05 h(-1) by using this model and the highest yield for glucoamylase production by A. niger reached 0.127 g glucoamylase/g glucose. The black-box model constructed in this study successfully described the glucoamylase production by A. niger and the result of the model fitted the measured value well. The black-box model could guide the design and optimization of glucoamylase production by A. niger.
Aspergillus niger ; metabolism ; Batch Cell Culture Techniques ; Carbon ; Culture Media ; Glucan 1,4-alpha-Glucosidase ; biosynthesis ; Glucose ; Industrial Microbiology ; methods ; Oxygen

The aim of this study is to develop a synthetic medium suitable for 13C metabolic flux analysis (13C-MFA) of Streptomyces rimosus. The cell growth rate and oxytetracycline production by S. rimosus M4018 were compared when M4018 cells were growth on the optimized chemically defined media with organic nitrogen sources or inorganic nitrogen sources. First, a synthetic medium contained KNO3 as the main nitrogen source was screened, then optimized by a response surface method. Using this new medium, the oxytetracycline yield was increased from 75.2 to 145.6 mg/L. Furthermore, based on the 13C-MFA, we identified that Entner-Doudoroff pathway does not exist in S. rimosus cells cultured in a chemically defined medium with feed of 100% 1-13C labeled glucose. This study is helpful for subsequent 13C-MFA application of S. rimosus.
Carbon Isotopes ; analysis ; Culture Media ; chemistry ; Metabolic Flux Analysis ; Nitrogen ; chemistry ; Oxytetracycline ; biosynthesis ; Streptomyces rimosus ; metabolism

13 C isotopic abundance of intracellular free amino acid with a characteristic of fast- turnover can quickly reflect changes in intracellular metabolic state. But the concentration of intracellular free amino acid is low, the existed 13 C isotope detection method based on GC-MS can not satisfy the requirement with full scan mode. In this study, the selected ion monitoring method was used to detect accuracy higher likelihood of analysis of 13 C isotopic abundance of free intracellular amino acid. First, in the full scan mode we analyzed of the fracture law of different amino acids, found the feature corresponding to each amino acid fragments, and established 16 kinds of free intracellular amino acids characteristic fragment library. Then using this characteristic fragment library, only specific m/z signal was detected in sample analysis, which realized the selected ion monitoring and improved the quality of signal. The results of amino acid standards showed that the signal-to-noise ratio, measurement precision and accuracy were improved by 17, 2. 0 and 3. 8 times compared with the full scan mode. In the analysis of coenzyme Q10 producing strains of samples, this method was successfully used to detect isotopic abundance of 8 kinds of free intracellular amino acids. This method plays an important role in the detection of 13 C isotopic abundance of the intracellular free amino acid in cell metabolism research.

A method for measuring 13C isotopic abundance of intracellular metabolites of Saccharopolysporaerythraea by ultra-high performance liquid chromatography (UPLC)-triple quadrupole mass spectrometry was established.First, the chromatographic conditions of UPLC were optimized, and then the MS conditions such as unique tube lens voltage, collision energy, and ion pair were optimized.On the bases of length of the parent and daughter ions carbon chains and whether the daughter ions contain 13C atoms, the one-to-one method, one-to-many method and SIM method were established for measuring 13C isotopic abundance.Then these methods were used to measure naturally labeled intracellular metabolite standards and 13C labeled samples, and according to the gap between the experimental value and the theoretical value, the best method was established for each metabolite of different characteristics.The results showed that one-to-one method was most effective for measuring the metabolites of daughter ions not containing 13C atoms represented by sugar phosphates, one-to-many method was the best for measuring the metabolites of both parent and daughter ions containing 13C short carbon chains represented by carboxylic acids, SIM method could play a role in measuring the metabolites of both parent and daughter ions containing 13C long carbon chains represented by coenzyme A.This method had a good measurement precision and could be applied to the measurement of Saccharopolysporaerythraea intracellular metabolites, which contributed to the consequent study of metabolic mechanism and the efficient expression of erythromycin.

Recently the methylotrophic Pichia pastoris,with many advantages such as high expression,stable genetics and protein secretion,has been used extensively as a host expressing heterologous proteins.The optimal seed medium among seven media MM,MD,MGY,BMGY,YMPD,YMPGy and MGyB is BMGY with addition of 4mL/L PTM1 The high density synthesized medium in shake flask culture is as follows: Glycerol 4%(NH 4) 2SO 4 10g/L,CaSO 4 0.93g/L,K 2SO 4 18 2g/L,MgSO 4?7H 2O 14 9g/L,add 0.1mol/L PBS(pH=6 0) to 1 0 liter.The harvested yeast cell optical density (OD 600 ) reached 65 or more after 26 hours cultivation.By analysis of SDS\|PAGE,the results of Pichia pastoris culture by methanol inducement for 72 hours showed that the expression of recombinant human serum albumin had been achieved by methanol inducement after 12 hours,and the mount of targeted protein reached the summit after 24 hours inducement by methanol.The high density synthesized medium in shake flask culture in this experiment,which is similar to the mediums of batch fermentation and batch\|fed fermentation,is benefit to direct the P.pastoris fermentation in the fermentor.