Prospective experimental studies on the renal protective effect of ulinastatin after paraquat poisoning

BACKGROUND:Paraquat(PQ) is an effective herbicide and is widely used in agricultural production,but PQ poisoning is frequently seen in humans with the lung as the target organ.Currently,there are many studies on lung injury after PQ poisoning.But the kidney as the main excretory organ after PQ poisoning is rarely studied and the mechanisms of this poisoning is not very clear.In this study,we observed the expression of caspase-3 and livin protein in rat renal tissue after PQ poisoning as well as the therapeutic effects of ulinastatin.METHODS:Fifty-four Sprague-Dawley(SD) rats were randomly divided into three experimental groups:control group(group A),paraquat poisoning group(group B) and ulinastatin group(group C),with 18 rats in each group.Rats in group B and group C were administered intragastrically with 80mg/kg PQ,rats in group C were injected peritoneally with 100 000 U/kg ulinastatin once a day,while rats in group A were administered intragastrically with the same volume of saline as PQ.At 24,48,72 hours after poisoning,the expression of livin in renal tissue was detected by Westen blotting,the expression of caspase-3 was detected by immunohistochemistry,and the rate of renal cell apoptosis was tested by TUNEL detection.The histopathological changes were observed at the same time.RESULTS:Compared to group A,the expression of caspase-3 in the renal tissue of rats in groups B and C increased significantly at any time point.Compared with group B,the expression of caspase-3 in renal tissue of rats in group C decreased.Compared with group A,the expression of livin in renal tissue in rats of groups B and C increased significantly at any time point(P<0.01),especially in group C(P<0.01).TUNEL method showed that the rate of renal cell apoptosis index was higher in group B at corresponding time points than in group A(P<0.01),and was lower in group C at corresponding time points than in group B(P<0.01).CONCLUSION:UTI has a protective effect on the renal tissue of rats after paraquat poisoning through up-regulating the expression of livin and down-regulating the expression of caspase-3,but the regulation path still needs a further research.

Expression of heat shock protein 70 in lung tissuesof acute paraquat poisoned rats and interventionof ulinastatin

BACKGROUND： Paraquat （PQ） is an effective herbicide and is widely used in agricultural production, but PQ poisoning is frequently seen in humans with the lung as the target organ. Clinically pulmonary pathological changes are often used to predict the severity and prognosis of the patients. In this study, we observed the expression of heat shock protein 70 （HSP70） in rat lung after PQ poisoning and to investigate the therapeutic effects of ulinastatin.METHODS： Seventy-two adult healthy SD rats were randomly divided into a control group （group A, n=24）, a poisoning group （group B, n=24）, and an ulinastatin group （group C, n=24）. The rat models of acute PQ poisoning were established by intra-gastric administration of 80 mg/kg PQ to rats of groups B and C, and the rats of group C were intra-peritoneally injected with 100 000 IU/kg ulinastatin 30 minutes after poisoning. The expression of HSP70 in lung tissue was observed, and W/D and histopathological changes in the lung tissue were compared 12, 24, 48 and 72 hours after poisoning. The expression of HSP70 in the lung tissue was assayed by using RT-PCR. All quantitative data were processed with one-way analysis of variance to compare multiple sample means.RESULTS： Compared to group A, the expression of HSP70 in the lung of rats in groups B and C increased signi？ cantly at all intervals （P〈0.05）. The pathological changes in lung tissue of rats with PQ poisoning included congestion, leukocytes in？ ltration and local hemorrhage, whereas those of group C were signi？ cantly lessened.CONCLUSION： Ulinastatin may ameliorate acute lung injury to some extent after PQ poisoning in rats by enhancing the expression of HSP70.

HSP70 regulates Bcl-2 to inhibit endothelial cell damage in emergency sepsis patients

Objective:To analyze the mechanism of HSP70 regulating endothelial cell injury in patients with acute sepsis.Methods:From February 2017 to December 2018,3 patients with acute sepsis in our hospital were selected as the observation group,and 3 patients with fracture undergoing surgical treatment were selected as the control group.The endothelial cells were extracted and divided into blank subgroup,10 mg/L,50 mg/L and 100 mg/L subgroups.The cell viability of each group was detected by MTT,the nucleus morphology was observed by fluorescence microscope,and autophagosomes of endothelial cells were observed by transmission electron microscope,and then the level of Bcl-2,Beclin-1 andβ-actin protein expression were detected.Results:HSP70 intervention can effectively improve the endothelial cell vitality of patients with acute sepsis.The cell viability of 100 mg/L subgroup was the highest in the observation group and the control group,and the cell viability of the blank subgroup was the lowest,and the difference was statistically significant(P<0.05).Compared with the control group,the endothelial cell nuclear defect of acute sepsis patients was serious.HSP70 intervention can effectively improve the nuclear morphology,autophagy morphology and structural morphology,and the 100 mg/L subgroup had the best nuclear morphology and autophagy morphology.HSP70 intervention can effectively improve the levels of Bcl-2 and beclin-1 in endothelial cells of patients with acute sepsis.The levels of Bcl-2 and beclin-1 were the highest in the 100 mg/L subgroup of the observation group and the control group,and the lowest in the blank subgroup,and the difference was statistically significant(P<0.05).Conclusion:HSP70 can effectively regulate the level of Bcl-2 in endothelial cells of patients with acute sepsis,which effectively inhibit cell apoptosis and alleviate cell skin damage.

OPTIMAL CONTROL FOR A NONLINEAR n-DIMENSIONAL COMPETING SYSTEM WITH AGE-STRUCTURE

This paper is concerned with optimal harvesting control of a first order partial differential equation system representing a nonlinear n-dimensional competitive population model with age-structure. By the Ekeland＇s variational principle, the existence and unique char- acterization of the optimal control strategy are established. The optimality conditions for the control problem are obtained by the concept of the normal cone.