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During the traumatic brain injury (TBI), improved expression of circulatory miR-21 serves as a diagnostic feature. Low levels of exosome-miR-21 in the brain can effectively improve neuroinflammation and blood-brain barrier (BBB) permeability, reduce nerve apoptosis, restore neural function and ameliorate TBI. We evaluated the role of macrophage derived exosomes-miR-21 (M-Exos-miR-21) in disrupting BBB, deteriorating TBI, and Rg1 interventions. IL-1
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Objective To investigate influence of exogenous insulin in all-in-one parenteral nutrition on blood glucose in infants with very low birth weight (VLBW). Methods Forty-two infants with VLBWI admitted to the department of pediatrics of Xuzhou Hospital affiliated to Southeast University during September 2005 to March 2009 were randomly assigned to Group Ⅰ ( n = 13 ) with exogenous insulin added to all-in-one parenteral nutrition at infusion rate of 0.4 U·kg-1·h-1,GroupⅡ(n = 13) with exogenous insulin at infusion rate of 0.1U·kg-1·h-1 and Group Ⅲ (n = 16) with no exogenous insulin added.Their blood glucose was monitored every two hours. Chi-square test was used for comparing difference in blood glucose abnormality between the three groups and association between blood glucose levels at admission and during hospitalization was analyzed with Spearman correlation. Results Incidence of hyperglycemia and hypoglycemia was 10. 9 percent (29/265) and 18. 1 percent (48/265) in Group Ⅰ, 20. 8 percent (59/284) and 14. 1 percent (40/284) in Group Ⅱ , and 20. 5 percent (61/298) and 11.7 percent (35/298) in Group Ⅲ, respectively. There was significant difference in incidence of hyperglycemia between Groups Ⅰ and Ⅱ ( x2 = 9. 844, P = 0. 002 ) and between Groups Ⅰ and Ⅲ ( x2 = 9. 478, P = 0. 002 ), but no significant difference in it between Groups Ⅱ and Ⅲ ( x2 = 0. 008, P = 0. 928 ). There was significant difference in incidence of hypoglycemia between Groups Ⅰ and Ⅲ ( x2 = 4. 526, P =0. 033 ), but no significant difference in it between Groups Ⅰ and Ⅱ (x2 =1.653, P=0. 199) or between Groups Ⅱ and Ⅲ (x2 =0.709, P =0.400).No significant correlation between endogenous blood insulin level at admission and during hospitalization( r = 0. 082, P = 0. 661 ) was found. Conclusions Blood glucose in infants with VLBW can not be regulated timely by their endogenous insulin itseff. Exogenous insulin added to all-in-one parenteral nutrition at infusion rate of 0. 1 U · kg-1 · h-1 may not significantly reduce incidence of hyperglycemia,while incidence of hypoglycemia can be reduced by exogenous insulin at infusion rate of 0. 4 U · kg- 1 · h -1 that can increase incidence of hypoglycemia Therefore, exogenous insulin is not recommended to be prophylactically added to all-in-one parenteral nutrition for infants with VLBW.
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Objective This study was carried out to compare chnical efficiency of methylprednisolone (MP) and dexamethasone (Dex) and their effects on Th cytokines in asthmatic children.Methods A total of 39 children with moderate and severe asthma at acute exacerbation were randomly divided into two groups, one (A) with MP 1 -2 mg/kg (n=21) and the other (B) with Dex 0.25 -0.75 mg/kg (n= 18),every 12 -24 h by intravenous drip.Scores of respiratory effort and peak expiratory flow rate prior to and three days after treatment in the asthmatic children aged over five years were evaluated,respectively,as well as the time of wheezing vanishing after treatment.Serum levels of interleukin-2 (IL-2) and IL-4 were determined by radioimmunoassay (RIA) prior to and three days after treatment,respectively.Results There was statistically significant difference in the time of wheezing vanishing between groups A and B (P = 0.042).Three days after treatment,PEER was significantly higher in group A than that in group B (P = 0.025).No statistically significant difference in serum IL-2 and IL-4,as well as ratio of IL-2/IL-4,was found in group B prior to and three days after treatment (P>0.05).Statistically significant difference in serum IL-2 was not observed in group B prior to and three day after treatment (P>0.05),and serum IL-4 decreased significantly (P=0.001) and ratio of serum IL-2/IL-4 (P=0.027) increased significantly three days after treatment than those prior to treatment.No significant correlation between respiratory-effort scores and ratio of serum IL-2/IL-4 prior to treatment was found (P=0.613).Conclusions Up-regulation of IL-2,or inhibition of release of IL-4,probably is not the main anti-inflammatory mechanism of dexamethasone.Methylprednisolone has little effect on serum IL-2,but can effectively reduce serum IL-4, thus increasing the ratio of serum IL-2/IL-4 and counterbalancing function of the Thl/Th2 cells.
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It is very important to obtain high yield mutant strains on the base of metabolic flux analysis of Actinobacillus succinogenes S.JST for the industrial bioconversion of succinic acid. The metabolic pathway was analized at first and the flux of the metabolic networks was calculated by matrix. In order to decrease acetic acid flux, the strains mutated by soft X-ray of synchronous radiation were screened on the plates with high concentration of fluoroacetic acid. For decreasing the metabolic flux of ethanol the site-directed mutagenesis was carried out for the reduction of alcohol dehydrogenase(Adh) specific activity. Then the enzyme activity determination and the gene sequence analysis of the mutant strain was compared with those of the parent strain. Metabolic flux analysis of the parent strain indicated that the flux of succinic acid was 1.78(mmol/g/h) and that the flux of acetic acid and ethanol were 0.60 (mmol/g/h) and 1.04( mmol/g/h), respectively. Meanwhile the metabolic pathway analysis showed that the ethanol metabolism enhanced the lacking of H electron donor during the synthesis of succinic acid and that the succinic acid flux was weakened by the metabolism of byproducts ethanol and acetic acid. Compared with the parent strain, the acetic acid flux of anti-fluoroacetic mutant strain S.JST1 was 0.024 (mmol/g/h), decreasing by 96%. Then the enzyme determination showed that the specific activity unit of phosphotransacetylase(Pta) decreased from 602 to 74 and a mutated site was founded in the pta gene of the mutant strain S.JST1. Compared with that of the parent strain S.JST1 the ethanol flux of adh-site-directed mutant strain S.JST2 was 0.020 (mmol/g/h), decreasing by 98%. Then the enzyme determination showed that the specific activity unit of Adh decreased from 585 to 62 and the yield of end product succinic acid was 65.7 (g/L). The interdiction of Adh and Pta decreased the metabolism of byproducts and the H electron donor was well balanced, thus the succinic acid flux was strengthened by the redundant carbon flux from these byproducts. The mutant strain S.JST2 obtained in this paper deserves being extended to application of industrial fermentation.