Objective To explore the causal relationship between immune cell-mediated intestinal flora and myasthenia gravis(MG)by two-sample Mendelian randomization(MR)analysis.Methods The published Genome-Wide Association Study(GWAS)covering a total of 412 intestinal flora phenotypes and 731 immune cell phenotypes were used as exposure factors.The GWAS data of MG were obtained from the IEU Open GWAS project database.The sample size of the case group was 1278 cases,and the sample size of the control group was 33652 cases,containing 22357218 SNP.The subjects were all Europeans.Firstly,a two-sample MR analysis method was used to verify the causal relationship between intestinal flora and MG,immune cells and MG,intestinal flora and immune cells.Re-verse MR verifies the positive relationship.At the same time,sensitivity analysis was carried out,including heterogeneity test,level multi-effect test,leave-one-out sensitivity analysis and a series of verification analysis.Finally,the mediating effect of immune cells in the causal relationship between intestinal flora and MG was determined by two-step MR analysis.Results The causal relationship be-tween immune cell-mediated intestinal flora and MG was analyzed by inverse-variance weighted(IVW)method.The results showed that:Barnesiella(OR=1.835,95％CI:1.388-2.426),Barnesiella_intestinihominis(OR=1.961,95％CI:1.473-2.612),Eu-bacterium_biforme(OR=1.429,95％CI:1.155-1.766),Bacteroides_clarus(OR=1.220,95％CI:1.017-1.464),Roseburia_unclassified(OR=1.260,95％CI:1.053-1.509)were positively correlated with MG(P＜0.05).Streptococcus_parasanguinis(OR=0.715,95％CI:0.528-0.967)and Roseburia_intestinalis(OR=0.712,95％CI:0.517-0.982)were negatively correlated with MG(P＜0.05).The coefficient product method showed that the mediating effect of CD8dim％leukocyte in the inhibition of MG de-velopment by Roseburia_intestinalis accounted for 9.25％of the total effect.Conclusion Roseburia_intestinalis inhibits the occurrence and development of MG through CD8dim％leukocyte as an intermediary factor.This may provide new reference and basis for the preven-tion,treatment and rehabilitation of MG in the future.

Objective To explore the causal relationship between immune cell-mediated intestinal flora and myasthenia gravis(MG)by two-sample Mendelian randomization(MR)analysis.Methods The published Genome-Wide Association Study(GWAS)covering a total of 412 intestinal flora phenotypes and 731 immune cell phenotypes were used as exposure factors.The GWAS data of MG were obtained from the IEU Open GWAS project database.The sample size of the case group was 1278 cases,and the sample size of the control group was 33652 cases,containing 22357218 SNP.The subjects were all Europeans.Firstly,a two-sample MR analysis method was used to verify the causal relationship between intestinal flora and MG,immune cells and MG,intestinal flora and immune cells.Re-verse MR verifies the positive relationship.At the same time,sensitivity analysis was carried out,including heterogeneity test,level multi-effect test,leave-one-out sensitivity analysis and a series of verification analysis.Finally,the mediating effect of immune cells in the causal relationship between intestinal flora and MG was determined by two-step MR analysis.Results The causal relationship be-tween immune cell-mediated intestinal flora and MG was analyzed by inverse-variance weighted(IVW)method.The results showed that:Barnesiella(OR=1.835,95％CI:1.388-2.426),Barnesiella_intestinihominis(OR=1.961,95％CI:1.473-2.612),Eu-bacterium_biforme(OR=1.429,95％CI:1.155-1.766),Bacteroides_clarus(OR=1.220,95％CI:1.017-1.464),Roseburia_unclassified(OR=1.260,95％CI:1.053-1.509)were positively correlated with MG(P＜0.05).Streptococcus_parasanguinis(OR=0.715,95％CI:0.528-0.967)and Roseburia_intestinalis(OR=0.712,95％CI:0.517-0.982)were negatively correlated with MG(P＜0.05).The coefficient product method showed that the mediating effect of CD8dim％leukocyte in the inhibition of MG de-velopment by Roseburia_intestinalis accounted for 9.25％of the total effect.Conclusion Roseburia_intestinalis inhibits the occurrence and development of MG through CD8dim％leukocyte as an intermediary factor.This may provide new reference and basis for the preven-tion,treatment and rehabilitation of MG in the future.

Organ transplantation is an effective treatment for end-stage organ failure. However, organ shortage has always been a common problem faced by countries around the world. The recognition and active participation of intensive care unit (ICU) medical staff in organ donation contributes to promoting the development of organ donation, thereby alleviating the shortage of donor organ. In this article, the key strategies of ICU donor management to promote organ donation and the key strategies of ICU medical staff management to promote organ donation were summarized, aiming to provide reference for organ donation practitioners (especially ICU medical staff) and jointly facilitate the professional development of organ donation.

Objective To discuss the clinical characteristics and prognosis of 15 children with hand foot and mouth disease (HFMD) and acute flaccid paralysis (AFP) who were admitted to Beijing Ditan Hospital during the outbreak of HFMD in 2008. Method The epidemiology, clinical manifestations, cerebrospinal fluid (CSF),magnetic resonance imaging and prognosis of 15 children with HFMD and AFP were retrospectively reviewed. The recovery of the patients' affected extremities were monitored for 4 weeks. Results The mean age of these patients was (22.47 ± 20.68) months (range: 5～72 months). Acute paralysis developed (3.47 ± 1.68) days after the onset of fever and progressed to maximum severity within (1～2) days. Poliomyelitis-like syndrome was observed in all cases. Of the 15 cases, 10 had monoplegia of lower limbs, two had paraplegia, one had monoplegia of upper limbs and two had quadriplegia. In these cases, the muscle power varied from level 0 to level 4, and six even showed no muscle power in their affected extremities. Thirteen cases developed neurologic complications (encephalitis, meningitis or ataxia) and three had transient urinary retention. Cerebrospinal MRI examination in eight cases showed hyperintense lesions on T2-weighted images, predominantly in the impaired anterior horn regions of the spinal cord (C2～C7 for cases with upper extremity impairments and T12～L1 for cases with lower extremity impairments), and displayed long T1 signals and long T2 signals. In addition, the midbrain, brain-stem or medulla was also involved in four cases who also contracted encephalitis or meningitis. The muscle strength in 11 patients with single lower extremity impairment showed improvements in the distal limb muscles within 4～8 days, and the other cases showed recovery 2～3 weeks later. Conclusions HFMD in combination with AFP most commonly occurs in children aged less than 2 years old. Acute paralysis develops during the early stage of infection and progresses to a maximum severity within 2 days. In most cases described here, paralysis occurred in a single lower extremity and recovered more rapidly than those with all four limbs affected or with single upper extremity impairment . MRI examination is particularly valuable for the diagnosis and prognosis of AFP because of its high sensitivity and accuracy.