Objective To study the effect of tail-suspending on myostatin(MSTN)expression in the soleus muscle of rats.Methods The MSTN mRNA levels in soleus muscle of tail-suspended and normal control rats were measured and compared.Results The MSTN mRNA in soleus muscle of tail-suspended rats was 2.2 times(hind limb unloading for 14 days)and 3.5 times(hind limb unloading for 30 days) higher than that in normal control rats (P<0.05).The relative wet weight of the soleus muscle in tail-suspended rats was decreased by 11%(unloading 14 days)and 1 9%(unloading 30 days),respectively,compared with that in normal control rats.Conclusion The expression of MSTN mRNA is elevated in the soleus muscle of tail-suspended rats,probably due to atrophy of the soleus muscle.

Objective To detect the physico-chemical properties , cytotoxicity and antimicrobial activity of dressings containing Ag +.Methods The morphology of this dressing was shown by the scanning electron microscope ( SEM ) .The cytotoxicity was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) method.Using the shake flask test method , the antibacterial effect of dressings was studied .Result There was no significant difference in the water vapor transmission rate between the dressings (P>0.05).Compared with the alginate calcium dressing ,silver ion dressings had a stronger swelling rate .A higher ion concentration would lead to a much larger swelling rate and slower degradation . A lower cytotoxicity was exhibited among the dressings .The silver ion dressing had stronger bacteriostasis to Gram-positive ( G+) and Gram-negative ( G-) bacteria than the alginate calcium dressing .Conclusion The experiment has proved that the silver ion dressing has stronger antibacterial activity and lower cytotoxicity , and it is more effective for wound surface healing, with a shortened treatment course .

In the last few decades, with the development of recombinant DNA technology, metabolic engineering has made tremendous advances. Synthetic biology is a newly and rapidly emerging discipline. It has great potential in assisting and simplifying the study of metabolic engineering. This review focuses on the recent development of synthetic biology and its application in optimizing metabolic pathway and engineering cellular chassis.
Genetic Engineering ; methods ; Industrial Microbiology ; methods ; Metabolism ; Synthetic Biology ; trends

One pair of primers were designed and synthesized on the base of the cDNA sequence encoding Schizosaccharomyces pombe N-glycanase reported on the GenBank. The cDNA sequence encoding Peptide N-glycanase was cloned from the Schizosaccharomyces pombe by RT-PCR. And then the RT-PCR product was cloned into the expression vector pET-15b. The expression vector pET-15b(+)/Png1p was transformed into E. coli BL21(DE3). The results showed that the relative molecular weight of the enzyme was determined to be approximately 39 kD using SDS-PAGE. The expression products after induction and purification can catalyze the cleavage of N-linked oligosaccharides from glycoprotein coped with heat, but have no action on the native glycoprotein with the help of DTT. The percentage of deglycosylated RNase B treated with equate Png1p in different reaction temperature, pH, concentration of DTT and denatured temperature showed that the optimum temperature, the optimum pH is 30 degrees C; the optimum concentration of DTT is 10 mmol/L and the optimum denatured temperature is 100 degrees C.
Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Glycosylation ; Hydrogen-Ion Concentration ; Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase ; biosynthesis ; genetics ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; Schizosaccharomyces ; enzymology ; genetics ; Temperature

The China-European environmental biotechnology cooperation research project on the biodegradation of waste plastics is jointly funded by the National Natural Science Foundation of China (NSFC) and the European Commission (EC), and aims to encourage Chinese and European scientists to carry out substantive research in the field of "Microorganism communities for plastics biodegradation". The goal of the project is to use the metabolic capacity of microbial communities to degrade petrochemical plastics that are easy to cause environmental pollution into monomers and small molecules, thereby realizing the biosynthesis of high-value biochemicals by microorganisms. This can not only solve the problem of plastic pollution, but also "turn waste into treasure" and create higher economic benefits. The China-European cooperative research project will promote in-depth cooperation between scientists from both sides in the field of synthetic biology, and help the two sides establish long-term and stable international exchanges and cooperation. Both China and the EU will work to solve the global plastic pollution problem, form a strategic force of science and technology, and jointly open a new chapter in the field of resource utilization of non-degradable plastics.
Biodegradation, Environmental ; China ; Europe ; Plastics

Based on carbon metabolic pathway analysis of Escherichia coli MG1655, an aerobic succinate fermentation platform was constructed by knocking out five genes (ptsG, poxB, pta, iclR and sdhA), which was named E. coli QZ1111. Flask cultivation results showed that E. coli QZ1111 could accumulate succinate with a concentration of 26.4 g/L under aerobic conditions. The byproduct acetate was only 2.3 g/L. The production ratio of succinate and acetate reached 11.5:1.
Aerobiosis ; Escherichia coli ; genetics ; metabolism ; Fermentation ; Gene Expression Regulation, Bacterial ; Gene Knockout Techniques ; Protein Engineering ; methods ; Recombinant Proteins ; biosynthesis ; genetics ; Succinic Acid ; metabolism

Based on the fermentation analysis of Escherichia coli strains and cheap renewable resources suitable for polyhydroxybutyrate (PHB) production, we constructed a ptsG mutant of Escherichia coli DH5alpha. Application of E. coli DH5alpha mutant together with stress-induced system, we could produce PHB efficiently from cheap renewable sugar mixture by the simultaneous consumption of different sugars. Batch fermentation at lab scale (5 liter) showed that E. coli DH5alpha deltaptsG/pQKZ103 produced PHB from sugar mixture up to 84.6% of cell dry weight in 32 hours; meanwhile, the cell dry weight reached 8.24 g/L.
Escherichia coli ; genetics ; metabolism ; Fermentation ; Genetic Vectors ; genetics ; Hydroxybutyrates ; metabolism ; Metabolic Engineering ; methods ; Mutation ; Polyesters ; metabolism

Objective To evaluate the diagnosis and treatment of transcatheter small bowel radiography in intestinal obstruction.Methods From January 2016 to December 2016,150 cases of adhesive small intestine obstruction were divided into small bowel radiography group and control group.The long-term results were collected after 6-month follow-up.Results First aerofluxus time [(72 ± 5) h vs.(109 ±7) h],defecation [(89 ±8)h vs.(139 ± 17)h],extubation [(81 ± 18)h vs.(105 ± 17)h] and first oral intake [(84 ±6)h vs.(109 ±9)h] in catheter group were shorter compared with control group (all P ＜ 0.05).The accuracy of determining obstruction site were superior in catheter group than control group (92％ vs.63％,P ＜ 0.05).Conclusion Endoscopic transnasal ileus tube significantly relieves symptoms in the adhesive intestinal obstruction,the transcatheter small intestinal radiography helps determine the obstruction site.

Objective This study aims to investigate the frequency and characteristics of vascular involvement in Beh(c)et's disease (BD).Methods We enrolled patients who were hospitalized at Changhai Hospital affiliated Naval Medical University and who had been diagnosed with BD at discharge from January 1999 to July 2017.Patientswere divided into two groups,Vascular Beh(c)et's disease (VBD) group and non-VBD group,according to vascular involvement or not.We recorded and compared the demographicinformation,disease activity scores Beh(c)et’s Disease Current Activity Form (BDCAF),other systemic involvement and laboratory test results between the two groups.The clinical features of vascular involvement were analyzed.The measureddata were statistically analyzed with Student's t/t’ test or Mann-Whitney U test.The numerical data were statistically analyzed with x2 test or continuity correction x2 test.Results The total numbers of BD patients were 224,including 120 males and 104 females.Vascular involvements were found in 41 (18.3％) cases,including 34 males and 7 females.VBD was more common in males (28.3％ vs 6.7％,x2=17.388,P＜0.01).Of 41 VBD patients,11 cases (26.8％) had single vascular lesions,and 30 cases (73.2％) had multiple vascular lesions.Moreover,24 cases (58.5％) had arterial lesions,and 25 cases (61.0％) had venous lesions.Eight (19.5％) patients had both arterial and venous lesions.Compared to the non-VBD group,the VBD group had a higher frequency of cardiac involvement (22.0％ vs 3.8％,x2=16.592,P＜0.01),a higher disease activity index score (BDCAF) [3.0(2.0,4.0) score vs 2.0(2.0,3.0) score,U=2 609.5,P=0.001],higher levels of C-reactiveprotein (CRP) (14.45(4.97,64.08) mg/L vs 9.02(3.16,26.53) mg/L,U=2 809,P=0.046) and plasma homocysteine (Hcy) [(17.6±7.7) μmol/L vs (7.1±2.1) μmol/L,t'=7.894,P＜0.01].Conclusion VBD mainly affectsmales.It mainly presentsas multiple lesions.Moreover,patients in the VBD group havehigher frequency of cardiac complications,higher disease activity index scores (BDCAF),higher levels of CRP and Hcy than the non-VBD group.These results may have great valueto predict and diagnoseof VBD.

Laboratory evolution is an important approach to improve the performance of microorganisms. In the past decades, the methods for laboratory evolution have developed rapidly and applied widely. However, the commonly used evolution strategies for strains or specific proteins cannot achieve continuous mutation, and require multiple rounds of operation, therefore they are considered as a labor intensive process. The development of mutation and screening technologies have facilitated the development of continuous evolution in vivo and greatly improved the efficiency of laboratory evolution. The continuous in vivo evolution achieves in vivo mutation, perfectly combining mutation with screening to evolve a specific phenotype with minimal human intervention. This review summarizes the recent advances of in vivo continuous evolution technologies for either genome-scale mutation or evolution of specific proteins. The principles of these technologies and their applications are introduced. On this basis, the advantages and limitations of these technologies are discussed. We also give a perspective of future development of continuous in vivo evolution.
Directed Molecular Evolution ; Humans ; Mutation ; Phenotype ; Proteins