Proteomic analysis and qRT-PCR verification of temperature response to Arthrospira (Spirulina) platensis.

Arthrospira (Spirulina) platensis (ASP) is a representative filamentous, non-N2-fixing cyanobacterium that has great potential to enhance the food supply and possesses several valuable physiological features. ASP tolerates high and low temperatures along with highly alkaline and salty environments, and can strongly resist oxidation and irradiation. Based on genomic sequencing of ASP, we compared the protein expression profiles of this organism under different temperature conditions (15°C, 35°Cand 45°C) using 2-DE and peptide mass fingerprinting techniques. A total of 122 proteins having a significant differential expression response to temperature were retrieved. Of the positively expressed proteins, the homologies of 116 ASP proteins were found in Arthrospira (81 proteins in Arthrospira platensis str. Paraca and 35 in Arthrospira maxima CS-328). The other 6 proteins have high homology with other microorganisms. We classified the 122 differentially expressed positive proteins into 14 functions using the COG database, and characterized their respective KEGG metabolism pathways. The results demonstrated that these differentially expressed proteins are mainly involved in post-translational modification (protein turnover, chaperones), energy metabolism (photosynthesis, respiratory electron transport), translation (ribosomal structure and biogenesis) and carbohydrate transport and metabolism. Others proteins were related to amino acid transport and metabolism, cell envelope biogenesis, coenzyme metabolism and signal transduction mechanisms. Results implied that these proteins can perform predictable roles in rendering ASP resistance against low and high temperatures. Subsequently, we determined the transcription level of 38 genes in vivo in response to temperature and identified them by qRT-PCR. We found that the 26 differentially expressed proteins, representing 68.4% of the total target genes, maintained consistency between transcription and translation levels. The remaining 12 genes showed inconsistent protein expression with transcription level and accounted for 31.6% of the total target genes.

Risk factors and prognosis of new on-set postoperative atrial fibrillation undergoing isolated coronary artery bypass grafting surgery / 中华胸心血管外科杂志

Objective To analyse the risk factors and prognosis of new on-set postoperative atrial fibrillation in different age and gender groups.Methods The study is a retrospective analysis in 516 patients from a single center.All cases were divided into 5 groups by ages as:＜ 40 years (n =61),40-49 years (n =97),50-59 years (n =115),60-75 years (n =140),and ＞ 75 years(n =103).We retrospectively analysed the difference in the occurrence-and recurrence-rate of POAF,risk factors,feature of coronary artery in different age and gender groups.Results There were no statistics differences in the same age group.The major risk factors were smoking,family history of coronary artery disease and hyperlipaemia in age ＜40 years group and 40 ～ 49 years group.while the major risk factors were hypertension and diabetes in the 60-75 years group and age ＞ 75 years group.The percentage of smoking patients decreased along with adding age.There was obviously statistical difference in the recurrence-rate of POAF across all groups during 24 follow-up months (P ＜ 0.05).The number of coronary lesion was increased with age.There were more ostial lesions in the 60-75 years group and age ＞ 75 years group.Conclusion There are different risk factors and characteristics among POAF patients in different age and gender groups.It is of great significance for us that comprehensive clinical intervention measures are taken to prevent recurrence of AF.