Objective To explore the risk factors for methicillin-resistant Staphylococcus aureus (MRSA)infection of refractory wound,and provide reference for clinical prevention and control.Methods Clinical data of patients who were isolated Staphylococcus aureus (SA)from wound at the burn ward in a hospital from January 2006 to December 2013 were analyzed,patients were divided into four groups according to whether the isolated SA were MRSA and whether SA were from refractory wound or from non-refractory wound.Risk factors for MRSA infection of refractory wound were analyzed. Results A total of 112 isolates of SA were isolated from wound,statistical differences existed in the length of hospital stay,recent invasive operation,and recent antimicrobial use between patients in refractory wound MRSA group and refrac-tory wound methicillin-sensitive SA (MSSA)group (all P <0.05);non-conditional logistic regression analysis revealed that length of hospital stay>30 days (OR 95% CI :1.14-30.69)and recent invasive operation (OR 95% CI :1.41 -17.84) were independent risk factors for refractory wound MRSA infection.There were statistically differences in previous MRSA infection,burn depth,recent operation and recent antimicrobial use between refractory wound MRSA group and non-refrac-tory wound MRSA group(all P <0.05);non-conditional logistic regression analysis revealed that recent antimicrobial use (OR 95% CI :2.080-26.800)was independent risk factor for the persistence of MRSA infection of refractory wound. Conclusion Shortening the length of hospital stay,reducing invasive operation,and using antimicrobial agents ra-tionally are helpful for the prevention and control of MRSA infection of refractory wound.

Objective To investigate the characteristic of surgical treatment of burns in pediatrics patients. Methods From January 2006 to March 2012,47 pediatrics patients and 244 adult patients were received the surgical treatment in our hospital. The clinical data of two groups were analyzed retrospectively and compared. Results The female ratio in pediatric patients was higher than adult group,and almost patients received operation,especially plastic surgery and skin repair,with less surgeries of wound repair and infected surgeries. The preopera-tive physiological index between two groups was no significantly different. Conclusion On the premise of effective preoperative preparation, we could carry out surgical treatment of burns for pediatrics patients positively.

Alfalfa(Medicago sativa L.)is the most important legume forage crop worldwide with high nutritional value and yield.For a long time,the breeding of alfalfa was hampered by lacking reliable information on the autotetraploid genome and molecular markers linked to important agro-nomic traits.We herein reported the de novo assembly of the allele-aware chromosome-level genome of Zhongmu-4,a cultivar widely cultivated in China,and a comprehensive database of genomic variations based on resequencing of 220 germplasms.Approximate 2.74 Gb contigs(N50 of 2.06 Mb),accounting for 88.39％of the estimated genome,were assembled,and 2.56 Gb contigs were anchored to 32 pseudo-chromosomes.A total of 34,922 allelic genes were identified from the allele-aware genome.We observed the expansion of gene families,especially those related to the nitrogen metabolism,and the increase of repetitive elements including transposable elements,which probably resulted in the increase of Zhongmu-4 genome compared with Medicago truncatula.Population structure analysis revealed that the accessions from Asia and South America had rela-tively lower genetic diversity than those from Europe,suggesting that geography may influence alfalfa genetic divergence during local adaption.Genome-wide association studies identified 101 sin-gle nucleotide polymorphisms(SNPs)associated with 27 agronomic traits.Two candidate genes were predicted to be correlated with fall dormancy and salt response.We believe that the allele-aware chromosome-level genome sequence of Zhongmu-4 combined with the resequencing data of the diverse alfalfa germplasms will facilitate genetic research and genomics-assisted breeding in variety improvement of alfalfa.