ABSTRACT
Mytilus is a bivalve species with important economic and ecosystem value over worldwide. Mytilus antimicrobial peptides‚ with strong molecular diversity‚ has become a research focus. Two novel antimicrobial peptides were identified from Mytilus‚ with structural features that similar to arthropod defensins. However‚ the functional features and the immune mechanism of these two mussel defensins are unknown. For this reason‚ the two novel defensins‚ Arthropod like defensn-1 and -2 (ALD-1 and ALD-2‚ respectively)‚ were studied for the sequence features‚ expression profiles‚ and the dynamic expression pattern after different microbe induction. In addition‚ solid phase chemical synthesis technology was used for the synthesis of these two novel ALDs‚ and the function of synthesized peptides of ALD was verified. The results indicated that‚ two ALDs of M. coruscus have classical structure features similar to those of other arthropod defensins. These two ALDs are mainly presented in the tissues of mantle and digestive gland of mussel. The results also suggest that ALD-1 was expressed at higher levels in the gonads of males than in females (P<0. 05). The expression of two ALDs is developmentally regulated‚and both ALD-1 and ALD-2 were undetectable in larvae‚ but can be detected with high expression level at adult mussel with age of six months. The dynamic changes in the expression level of two ALDs after microbial induction were examined‚ and the results showed a marked increase in expression level observed in vivo for both ALDs. Interestingly‚ two ALDs showed different sensitivities to different microbes‚ indicating very complex responses during the mussel immune response. This observation strongly suggests the existence of different recognition mechanism or signal transduction pathway in mussels for the expression of ALD-1 and ALD-2. Moreover‚ both of two chemical synthesized ALDs showed significant antimicrobial activities against five tested microbes with an inhibition ratio of 20%-80%. These results provided basis for understanding the molecule mechanism of Mytilus immunology‚ and the function of novel Mytilus defensins‚ and thusly provided basis for the development of molecular resource for mussel antimicrobial peptides.
ABSTRACT
Objective: To explore GRACE (global registry of acute coronary events)score on short term prognosis of ST-segment elevation myocardial infarction (STEMI)in patients elder than 75 years with primary percutaneous coronary intervention(PCI). Methods: A total of 104 STEMI patients elder than 75 years with primary PCI in our hospital from 2011-11 to 2014-01 were studied. Based on GRACEscore at admission, the patients were divided into 2 groups: Lower/mid risk group, n=72 patients with GRACEscore at 112-154 (136.5±10.6) and High risk group, n=32 patients with GRACE score at 155-202(167.8±12.3). The baseline condition and outcomes were compared between 2 groups and the primary endpoint was 1 year mortality. Predictive value of GRACEscore on 1 year mortality was evaluated by ROC curve, the relationships between Lower/mid risk group, High risk group and clinical outcomes were assessed by log-ranksurvive curve andunivariate Cox regression analysis. Results: The area under ROC curve for GRACEscore predicting 1 year mortality was 0.788 with the sensitivity at 70.0%and specificity at 84.0 %.Univariate Cox regression analysis indicated that compared with Lower/mid risk group, High risk group had the higher risk of 1-year death (HR=5.75, 95% CI 1.486-22.256, P=0.0113); log-rank survive curve presented that High risk group had the higher 1 year mortality (21.9% vs 4.2%, P=0.0039). Conclusion: GRACE score may further distinguish the lower/mid risk and high risk populations in elder STEMI patients; it may also predict 1 year clinical prognosis.