OBJECTIVE To study the protective effects of Schwann cell derived neurotrophic factor (SDNF) on motoneurons of spinal anterior horn from spinal root avulsion induced cell death. METHODS Twenty SD rats were made the animal model of C6.7 spinal root avulsion induced motoneuron degeneration, and SDNF was applied at the lesion site of spinal cord once a week. After three weeks, the C6.7 spinal region was dissected out for motoneuron count, morphological analysis and nitric oxide synthase (NOS) enzyme histochemistry. RESULTS 68.6% motoneurons of spinal anterior horn death were occurred after 3 weeks following surgery, the size of survivors was significantly atrophy and NOS positive neurons increased. However, in animals which received SDNF treatment, the death of motoneurons was significantly decreased, the atrophy of surviving motoneurons was prevented, and expression of NOS was inhibited. CONCLUSION SDNF can prevent the death of motoneurons following spinal root avulsion. Nitric oxide may play a role in these injury induced motoneuron death.
ObjectiveTo explore the predictive value of fractional exhaled nitric oxide (FeNO) in the treatment response of adult asthmatic patients.
Methods64 adult outpatients with asthma from Peking Union Hospital between March and September 2013 were recruited in the study. All patients completed asthma control test (ACT) together with exhaled nitric oxide (FeNO) and pulmonary function test. Then the patients were classified into a higher FeNO group (n=33) and a normal FeNO group (n=31) according to FeNO level. All patients accepted regular inhaled ICS/LABA treatment (salmeterol and fluticasone 50/250). Three months later all patients reaccepted ACT,FeNO and pulmonary function test.
ResultsThe ACT score increased in all patients,and was significantly higher in the higher FeNO group than that in the normal FeNO group[22.07±5.49 vs. 19.23±5.48,t=2.893,P<0.05]. The complete control rate of the higher FeNO group was higher than that in the normal FeNO group (42.42% vs. 19.35%,χ2=3.960,P<0.05). The FEV1 and FEV1%pred of two groups both increased significantly (P<0.05),but there was no significant difference between two groups (P>0.05). Correlation analysis showed that FeNO and the declined rate of FeNO was negatively correlated with the ACT score(r=-0.302,P<0.05;r=0.674,P<0.01) and positively correlated with the improvement of ACT score (r=0.514,P<0.01;r=0.674,P<0.01). No significant correlation was found between FeNO and FEV1 or FEV1%pred.
ConclusionThe effect of ICS/LABA therapy is better for asthma patients with higher FeNO. FeNO can be used for predicting the response to ICS/LABA therapy in patients with asthma and guiding the treatment.
Objective To assess the variation and its significance of messenger ribonucleic acid(mRNA) expression of endothelial nitric oxide synthase (eNOS) in allografts of common carotid transplantation model in white rabbits. Methods To establish an animal model of common carotid transplantation in vivo, 30 rabbits were divided into four groups with random number table. Group A (n=3): autografts; group B (n=9): allografts with the least treated; group C (n=9): allografts treated by penicillin/streptomycin and preserved under room temperature; group D (n=9): allografts treated by penicillin/streptomycin and cryopreserved in liquid nitrogen. All the transplanted grafts were harvested 1-3 weeks later, then compared and evaluated the histomorphological variation and eNOS mRNA expression. Results The vascular structures of autografts in group A were kept approximately normal, only a few infiltration of inflammatory cells could be found. The structural variations of allografts in other trial groups behaved similarly as, intima proliferation in the 1st week, intima hyperplasia in the 2nd week, and both intima and media hypertrophy in the 3rd week. And also there seemed that luminal thrombosis could be found in all the allografts. Allografts in group B were destructed utmost the worst in all the groups. The expression of eNOS mRNA in allografts of group B was significantly less than that in other groups (Plt;0.05). Conclusion The down-regulation of eNOS mRNA expression might lead to intima hyperplasia and thrombosis of allografts.
Medical nitric oxide (NO) flow control system plays an important role in lowering pulmonary hypertension. The design requirements, overall scheme, delivery system and hardware circuits of a medical NO flow control system were introduced in this paper. Particularly, we proposed the design of NO delivery system and hardware circuits in detail. To deliver nitric oxide of a variable concentration, the designed system needs to work with a ventilator. The system can adjust and monitor the inhaled nitric oxide concentrations and send out sound and light alarms when the inhaled nitric oxide concentrations are out of the set range. To validate reliability and efficacy, we measured specifications such as linearity, stability and response time of the proposed NO flow control system by continuously administering nitric oxide into inspiratory circuit to deliver nitric oxide of variable concentrations to a test lung. The experiments showed that these specifications can meet the desired requirements.
ObjectiveTo understand the effect of nitric oxide (NO) on the formation of hyperdynamic circulatory syndrome (HCS) and the influence of level of NO on HCS. MethodsAfter establishment of stable HCS in partial portal vein ligated rats,the quantity of NO in blood of portal vein and the activity of nitric oxide synthase (NOS) in liver were determined by pre and post injection of inhabitor of NOS (NGmethylLarginine) and hemodynamics was supervised simultaneously.ResultsThe quantity of NO was paralleled with the activity of NOS and was elevated markedly by 24 hours after operation and reached the top by 48 hours after surgery. These sequential changes were coincided with the dilation of general vascularture. There was a close relation between this changes and the formation of HCS.The quantity of NO and the activity of NOS were decreased significantly to the level of the control group after injection of NGmethylLarginine (LNMMA). LNMMA inhabited the activity of NOS and blocked the production of NO. HCS ameliorated obviously. ConclusionNO plays an important role in initiating the dilation of general vascularture and plays a critical role in the formation of HCS. HCS will be ameliorated obviously or be blocked completely by eliminating the effect of NO and the portal pressure will decreased significantly or recover to normal range.