Age-Related Changes on CD40 Promotor Methylation and Immune Gene Expressions in Thymus of Chicken.

One hundred and twenty one-day-old breeder cocks, included 15 cages of 8 birds each, were fed to learn the aging's effect on chicken's thymus immunity. At 2 (2-W) and 40 (40-W) weeks of age, one chicken each cage was randomly chosen and slaughtered to get the thymus sample. The results showed that thymus weight and morphology of 40-W group were far different from that of 2-W group, and exhibited a property of degeneration. Considering this phenotype variance, we analyzed the thymus' transcriptome to investigate the molecular mechanism that had been implicated in this phenotype diversity with age. Pearson correlation coefficients and principal component analysis indicated that two major populations corresponding to 40-W and 2-W group were identified, and 1949 differentially expressed genes (DEGs, 1722 up-regulated and 127 down-regulated) were obtained. Results of GO and KEGG pathway enrichment found that 4 significantly enriched KEGG pathways (Cytokine-cytokine receptor interaction, Intestinal immune network for IgA production, Toll-like receptor signaling pathway, AGE-RAGE signaling pathway in diabetic complications) related to immunoregulation were screened between 40-W and 2-W group. These results confirmed that thymus immunity of chickens had a strong age-related correlation. DEGs related to these 4 enriched KEGG pathways were suppressed in the thymus of 2-W group, this indicated that thymus immunity of 2-weeks-age chick was down-regulated. CD40 is involved in 3 of the 4 significantly enriched pathways, and it is critical for thymus immune-regulation. CD40 promoter methylation level of 2-W group was higher than that of 40-W group, it is consistent with the transcriptional differences of the gene. Our study concluded that thymus immunity of chicken was varied with age. Compared to the 40-W group, thymus immunity of 2-W group was down-regulated, and in a status of hypo-activation on the whole, and these effects might be related to CD40 suppression induced by promoter hyper-methylation of the gene.

[Meta-analysis on limb salvage and amputation for patients with local Enneking II osteosarcoma].

OBJECTIVE: To explore 5-year survival rate, local recurrence and metastasis rate of limb salvage and amputation for patients with local Enneking II osteosarcoma by Meta-analysis. METHODS: From January 1, 1970 to December 1, 2015, Subject term and keywords about limb salvage and amputation for local Enneking II osteosarcoma with pathological fracture were searched from Cochrane, PubMed, Ovid, Spinger Link, Embase, CNKI and WanFang database foundation. Literature confirm with inclusion criteria were choose and quality evaluation were performed. RevMan 5.0 software from Cochrane collaboration was used to perform Meta-analysis. Local recurrence, 5-year survival rate and odds ratio of transfer risk were compared between limb salvage and amputation group. RESULTS: Ten literatures confirm with inclusion criteria were included, and total sample size was 453. There were 315 patients in limb salvage group and 138 patients in amputation group. Five-year survival rate in amputation group was lower than that of limb salvage group [OR=2.88, 95%CI(1.40, 5.93)], however metastasis rate in limb salvage was less than that of amputation group [OR=0.43, 95%CI(0.20, 0.94)];there were no significant differences in local recurrence between two groups [OR=1.47, 95%CI (0.73, 2.97)]. Functional rehabilitation in limb salvage group was better than that of amputation group by MSTS systematic review. CONCLUSIONS: Limb salvage as an alternative in treating local Enneking II osteosarcoma with pathological fracture does not greatly increase risk of local recurrence or 5-year overall survival rate compared with amputation group, and has a lower risk of metastatic occurrence.