Salmonella enterica serovar Choleraesuis strain C500 is a live attenuated vaccine that has been widely used in Chi‐na for over 50 years to prevent piglet paratyphoid .However ,as C500 is obtained by chemical methods ,the genetic background of this strain remained unclear .In this study ,we compared the genomic differences between the virulent reference strain C 78‐2 and C500 by suppression subtractive hybridization combined with the mirror orientation selection method (MOS‐SSH ) .Six genes (asr ,ydgF ,ydgD ,ydgE ,rpoS ,and ptsG) were lost in C500 strain .Using real‐time PCR analysis ,we demonstrated that the genes regulated by rpoS ,a vital transcriptional regulator playing an important role in Salmonella infection ,were downregulated in C500 .Additionally ,the virulence of the rpoS mutant strain C78‐2ΔrpoS was 100 000 times lower than the parental strain in BALB/c mice .So loss of rpoS gene is the major factor leading to the attenuation of C500 strain .

Proteins encoded by regions of difference (RD) of Mycobacterium tuberculosis (MTB) constitute a potential source of specific antigens for vaccine development and immunodiagnosis .In the present study ,four genes named nrdF1 , pe_pgrs35 ,rv1985c ,and rv1986 from RD2 of MTB were cloned and overexpressed in E .coli with the induction of IPTG .Western blotting assay showed that these recombinant fusion proteins could well react with anti-His tag monoclonal antibody ,which in-dicated their good immunoreactivity .The serodiagnosis potential applications of these four proteins in bovine tuberculosis were further evaluated .An indirect ELISA assay was established by using fusion proteins as coating antigens for detection of their specific antibodies in bovine sera .The positive rates were 7 .35% in NrdF1 ,22 .06% in PE_PGRS35 ,16 .18% in Rv1985c and 16 .18% in Rv1986 respectively .All the results suggest that these fusion proteins have the potential application in serodiagnosis of bovine tuberculosis .

Objective To investigate the mechanism of icariin regulating the NLRP3 inflammasome in the treatment of cerebral ischemia-reperfusion injury in rats.Methods A rat model of focal cerebral ischemia-reperfusion was induced using the thread embolism method.At 24 hours post-operation,the rats were randomly allocated into a sham operation group,model group,butylphthalide group(70 mg/kg),ICA-low dose(20 mg/kg),ICA-middle dose(40 mg/kg),and ICA-high dose(80 mg/kg)groups.The corresponding drugs were administered by gavage at 10 mL/kg once a day for 13 consecutive days.One hour after the last administration,neurological function was scored.The cerebral cortex was observed by hematoxylin-eosin(HE)staining.Expression of interleukin(IL)-1β and IL-18 in the cerebral cortex was determined by immunohistochemistry.Expression of NLRP3,ASC,and Caspase-1 in the cerebral cortex was determined by Western Blot.Results In contrast to the sham operation group,there was a notable increase in neural function scores within the model group.The ischemic area around the visible cerebral cortex showed neuron necrosis at various level or glial cell proliferation,and the number of intact neurons was significantly reduced.IL-1β and IL-18 positive cells were significantly increased.Expression of NLRP3,ASC,and Caspase-1 was significantly increased(P＜0.01,P＜0.05).After treatment with icariin,the neural function score was decreased significantly.The degree of neuronal necrosis in the peri-ischemic area was significantly reduced,and the number of intact neurons was significantly increased.IL-1 β and IL-18-positive cells were decreased significantly.Expressions of NLRP3,ASC,and Caspase-1 were significantly decreased(P＜0.01,P＜0.05).Conclusions Treatment of cerebral ischemia-reperfusion injury by icariin may be related to regulation of the NLRP3 inflammasome.

Objective·To explore the effect of continuous nursing based on EMS[environment management(E),medicine direction(M)and self monitoring(S)]management mode on the preschool children with asthmatic diseases.Methods·A total of 67 children aged 0 to 6 years with asthmatic diseases admitted to the Department of Respiratory Medicine,Shanghai Children's Hospital,Shanghai Jiao Tong University School of Medicine from December 2019 to November 2020 were selected and divided into observation group(33 cases)and control group(34 cases)according to the random number table method,with 3 cases lost,and finally 32 cases in each group.The observation group received continuous nursing care based on EMS management mode,while the control group received routine care and discharge follow-up through the telephone.The children in the two groups were followed up at 1,3,and 6 months after discharge to evaluate the results of Test for Respiratory and Asthma Control in Kids(TRACK)and wheezing recurrence;Medication Adherence Report Scale for Asthma(MARS-A)and Nursing Job Satisfaction Questionnaire were used to evaluate medication adherence and nursing job satisfaction 6 months after discharge.Results·There was no significant difference in demographic characteristics and clinical baseline characteristics between the two groups.Repeated measures analysis of variance showed that effects of time,groups and the interaction of groups×time on the total score of TRACK were statistically significant.The total scores of TRACK in the observation group were significantly higher than those in the control group at 1,3,and 6 months after discharge(P=0.000).The total scores of TRACK in the two groups gradually increased with time(P=0.000).The recurrence rates of wheezing in the observation group were 25.0%,18.7%,and 9.4%at 1,3,and 6 months after discharge,which were significantly lower than those in the control group(50.0%,43.7%,and 31.3%,respectively,P<0.05).Generalized estimating equation analysis showed that there was a statistically significant difference between the two groups(P=0.013),and the intervention effect of the observation group was better than that of the control group(OR=0.292).The MARS-A score of the observation group was 4.519±0.395 at 6 months after discharge,which was significantly higher than that of the control group(3.994±0.739,P=0.001).The nursing job satisfaction of the observation group was significantly higher than that of the control group(P=0.000).There was a moderate positive correlation between the MARS-A score and the nursing job satisfaction(r=0.389,P=0.001).Conclusion·Continuous nursing based on EMS management mode can significantly improve the medication compliance and wheezing control level of the preschool children with asthmatic diseases,significantly reduce the recurrence rate of wheezing,and improve the nursing satisfaction.