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Objective:To analyze the plasma metabolomic characteristics of elderly patients with acute myocardial infarction and identify potential metabolic makers.Methods:Thirty elderly patients with acute myocardial infarction at the Second Affiliated Hospital of Soochow University were enrolled into the myocardial infarction group and thirty elderly people recruited at the physical examination center and meeting the inclusion criteria served as the control group.Plasma metabolites were measured by ultra-high performance liquid chromatography and quadrupole time-of-flight mass spectrometry.Information about metabolites was searched and sorted via the Kyoto Encyclopedia of Genes and Genomes(KEGG)database.Principal component analysis and orthogonal partial least square-discriminant analysis were carried out to compare overall trends and the Mann-Whitney U test was used for preliminary screening of differential metabolites in the two groups.Then the Mann-Whitney U test and a model of mutual information with random forests were used to analyze the importance of differential metabolites.A tandem liquid chromatography-mass spectrometry-based approach was subsequently performed for targeted detection of the content of differential metabolites in the two groups, and the t-test was used for comparison between the two groups. Results:There were no significant differences in the prevalence of hypertension, hyperlipidemia and diabetes mellitus between the two groups( P>0.05), while the plasma troponin T level in the myocardial infarction group was significantly higher than that in the control group, (2.16±0.36)μg/L vs.(0.26±0.03)μg/L( t=5.17, P<0.05). A clear difference in the overall trend was presented on the scatter plot of PCA and OPLS-DA, and a total of 32 differential metabolites met the preliminary screening criteria.Further analysis showed that pyrocatechol and 4 small peptides were closely correlated with grouping and was strongly predictive of group designation.Targeted quantification revealed the pyrocatechol concentration was(310.3±40.0)ng/L in the myocardial infarction group and(2 607.0±758.1)ng/L in the control group.The difference between the two groups was statistically significant( P<0.01). Conclusions:Plasma pyrocatechol has the potential to be metabolic marker of acute myocardial infarction in elderly patients and might be closely related to the occurrence and prognosis of this disease.
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Overexpression of exogenous lineage-determining factors succeeds in directly reprogramming fibroblasts to various cell types. Several studies have reported reprogramming of fibroblasts into induced cardiac progenitor cells (iCPCs). CRISPR/Cas9-mediated gene activation is a potential approach for cellular reprogramming due to its high precision and multiplexing capacity. Here we show lineage reprogramming to iCPCs through a dead Cas9 (dCas9)-based transcription activation system. Targeted and robust activation of endogenous cardiac factors, including GATA4, HAND2, MEF2C and TBX5 (G, H, M and T; GHMT), can reprogram human fibroblasts toward iCPCs. The iCPCs show potentials to differentiate into cardiomyocytes, smooth muscle cells and endothelial cells . Addition of MEIS1 to GHMT induces cell cycle arrest in G2/M and facilitates cardiac reprogramming. Lineage reprogramming of human fibroblasts into iCPCs provides a promising cellular resource for disease modeling, drug discovery and individualized cardiac cell therapy.
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The spike gene of porcine epidemic diarrhea virus (PEDV) was sequenced from 55 South China field strains isolated from pigs with symptoms of diarrhea. The sequences were compared within the set of field strains as well as with reference strains available in GenBank. Within the 55 South China PEDV field strains, the deduced amino acid sequence identities ranged from 93.8% to 99.9 % and ranged from 90.7% to 99.5% when compared with the foreign reference strains in GenBank. Our phylogenetic analysis showed that 10 of the 55 South China PEDV strains belonged to G1b and 45 belonged to G2b.
Subject(s)
Amino Acid Sequence , China , Databases, Nucleic Acid , Diarrhea , Porcine epidemic diarrhea virus , Sequence Analysis , SwineABSTRACT
Aim To investigate the apoptosis mechanism of human gastric cancer cell SGC-7901 induced by Omphalia lapidescens protein pPeOp.Methods CCK-8 and flow cytometry were used to detect the inhibitory effect of different concentrations of pPeOp(30, 60, 90 mg·L-1) on SGC-7901.The mRNA and protein expression of TNF-R1, Fas/FasL, Bcl-2, caspase-3 and caspase-8 were detected by qRT-PCR and Western blot.Results SGC-7901 cells were treated with different concentrations of pPeOp(30, 60, 90 mg·L-1) for 24 h.CCK-8 test showed that there was no significant difference between PVP group and the control group.The survival rate of the 5-Fu group was(53.71±7.34)% (P<0.05).The survival rates of pPeOp group(30, 60, 90 mg·L-1) were(80.95±6.25)%, (53.48±5.70)% and(44.61±6.50)%(r=0.984,P=0.016),respectively.Flow cytometry showed that the apoptosis rate of PVP group had no significant difference with control group, and the apoptosis rate of 5-Fu group was about(39.30±3.34)%(P<0.05).The apoptotic rates of pPeOp group(30, 60, 90 mg·L-1) were(10.90±1.25)%, (28.80±2.70)% and (32.00±3.50)%,respectively(P<0.05).The mRNA and protein expression levels of Bcl-2 were down-regulated,whereas the expression of TNF-R1, Fas/FasL, caspase-3 and caspase-8 were significantly up-regulated(P<0.05).Conclusions pPeOp can significantly inhibit the proliferation of gastric cancer cell line SGC-7901 and induce apoptosis in a dose-dependent manner.Death receptor pathway and mitochondrial pathway may be related to pPeOp-induced apoptosis of gastric cancer SGC-7901.
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Objective:In this study,a prokaryotic expression of the 3-ketosteroid-Delta (1)-dehydrogenase (KSDD) which came from Arthrobacter simplex was built.Moreover,in order to investigate the catalytic mechanism of KSDD and improve its stability,the structure of KSDD was predicted by computer and the critical sites were confirmed by site-directed mutations.Methods:The recombinant plasmid was constructed by eukaryotic expression vector pET-22b and the recombinant strain was constructed and expressed in Escherichia coli BL21 (DE3).High-performance liquid chromatography was used to determine the transformation rate of 4-AD to ADD.The KSDD structure and key sites were predicted by SWISS-MODEL.Site-directed mutations for the amino acid residues of key sites were constructed and activities of the mutations were detected.Results:The recombinant strain E.coli pET-22-ksdd was successfully constructed.It was induced to express the dehydrogenase by IPTG and the conversion rate of 4-AD to ADD was 27％ at 21 ℃.The structure of 3-ketosteroid-Delta (1)-dehydrogenase and the four key sites was analyzed by SWISS-MODEL.Four mutants,Y120R,Y320L,Y488F and G492Y were constructed.Mutants Y120R and Y488F were inactivated,so they were proved to be the key active sites of KSDD.The conversion rate of mutant Y320L was consistent with that of wild type,but the stability at 37 ℃ was improved.The conversion rate of mutant G492Y was 1.2 times of the wild type and the stability has been improved at 37 ℃.Conclusions:At present,there are few studies about the structure and catalytic mechanism of dehydrogenase.The active sites of the enzyme were verified by this study,which laid the foundation for the further study of the properties of the enzyme KSDD.