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Corresponding author:Tao Shaohua,Email:tsh1987﹫sina. com [Abstract] Continuous renal replacement therapy(CRRT)has become the standard treatment for acute kidney injury or severe metabolic derangement in the pediatric intensive care unit. Anticoagulation for circuit patency is the prerequisite during CRRT operation. Regional citrate anticoagulation for CRRT is more effective and safe than systemic or regional heparin. Regional citrate anticoagulation can decrease the risk of circuit loss and filter failure;furthermore,it is safer than systemic heparin anticoagulation for the reduction of bleeding risk. Complications of citrate anticoagulation ( such as acid－base imbalance and electrolyte disturbances)can be avoided by using an appropriate protocol and regu﹣lar monitoring. Therefore,citrate should be considered as the first choice for anticoagulation during CRRT in critically ill pediatric patients,and further studies are needed to evaluate the safety and efficacy of citrate anticoagulation in the pediatric population.
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Objective To preliminarily investigate the role of Vitamin C in cecal ligation and puncture-induced septic brain injury.Methods Male specific pathogen free (SPF) Sprague-Dawley male rats were randomly assigned into control group,sham operation group,sepsis group and sepsis therapy group.The rats in sepsis group were prepared by cecal ligation and puncture.The rats in sepsis therapy group were injected sodium ascorbate through the tail vein 3 h after the cecal ligation and punature procedure.The animals in other groups were subjected only to subcutaneous bolus injection of 9 g/L saline only.Animals were evaluated by neurologic reflex scores before sacrifice and brain tissues were quickly removed at the indicated time points.Reactive oxygen species (ROS),superoxide dismutase (SOD),malondialdehyde (MDA),nitric oxide (NO),inducible nitric oxide synthase (iNOS) and catalase (CAT) were determined by using enzyme assay kits.Hematoxylin-eosin (HE) staining was used to observe morphological changes in brain tissues.Results The survival rate of the sepsis group (30％ at 7th day) was significantly lower than that of the control group (100％ at 7th day)and sham operation group(100％ at 7th day).The survival rate of the sepsis therapy group (45％ at 7th day)was significantly higher than that of the sepsis group(P ＜ O.05).The neurological reflex assessment began to decrease at 6 h in sepsis group and reached the lowest at 24 h (6.00 ± 0.53).The sepsis therapy group (7.62 ± 0.52) was significantly higher (P ＜ 0.05) than the sepsis group and began to recover at 72 h (8.63 ±0.52).ROS,SOD,MDA,NO and iNOS in the sepsis group and the sepsis therapy group reached a peak at 24 h,which decreased at 72 h.The value in sepsis therapy group was significantly decreased than that in the sepsis group,and the difference was statistically significant(P ＜0.05).CAT changed in the opposition.The SOD/CAT in sepsis group was the highest 24 h after the operation,while the ratio in sepsis therapy group was significantly improved.SOD/CAT and MDA were positively correlated(r =0.968,P ＜ 0.05).HE staining showed significant damage to the brain tissue structure in the sepsis group,however some improvement was observed in the sepsis therapy group.Conclusion Vitamin C can significantly improve the survival rate and encephalopathy prognosis in the cecal ligation and puncture SD rat models.The mechanism may be related to the reduction of oxidative stress.
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Objective To research the protective effect of insulin(IN)on lipopolysaccharide(LPS)- induced impairments of rat cardiomyocytes H9c2,and the role of uncoupling protein 2(UCP2)in this process. Methods Using randomized controlled grouping,after cultured for 24 h,H9c2 cells were randomly divided into 5 groups as follows:con-trol group,LPS stimulation group(LPS group),LPS + 70 IU/ L IN group(IN 70 IU/ L group),LPS + 350 IU/ L IN group(IN 350 IU/ L group),and LPS + 700 IU/ L IN group(IN 700 IU/ L group). H9c2 cells in IN group were treated with 70 IU/ L,350 IU/ L or 700 IU/ L IN 15 min before LPS stimulation,and H9c2 cells in control group were treated with an equal volume of saline. After that,cells in group LPS and IN were treated with LPS for 24 h. Lactate dehydro-genase(LDH)in the culture was determined with LDH detecting assay kit. The activity of reactive oxygen species (ROS)and superoxide dismutase(SOD),and content of malonaldehyde(MDA)were determined by colorimetric detec-tion. Cell viability was evaluated by cell count kit - 8. The expressions of UCP2 in transcription and translation levels were detected through transcription polymerase chain reaction and Western blot respectively. Results The levels of LDH,MDA,and intracellular ROS in LPS group significantly increased compared with control group[LDH:(829. 3 ± 75. 3)U/ L vs(223. 5 ± 23. 6)U/ L,MDA:(60. 90 ± 5. 73)nmol/ mgprot vs(19. 70 ± 1. 99)nmol/ mgprot,ROS:(410. 2 ± 81. 6)U/ well vs(94. 3 ± 18. 5)U/ well,all P ﹤ 0. 05)],while the cell viability and SOD activity significantly decreased[cell viability:0. 822 ± 0. 058 vs 1. 012 ± 0. 023,SOD:(49. 20 ± 5. 81)U/ mgprot vs(89. 80 ± 2. 57)U/ mg-prot,all P ﹤ 0. 05]. And the mRNA and protein expressions of UCP2 in LPS stimulation group were up - regulated (1. 867 ± 0. 130 vs 1. 028 ± 0. 097,0. 288 ± 0. 018 vs 0. 180 ± 0. 008,all P ﹤ 0. 05). 350 IU/ L and 700 IU/ L IN inter-vention significantly decreased the levels of LDH,MDA and intracellular ROS[LDH:(568. 2 ± 35. 7)U/ L,(622. 8 ± 27. 6)U/ L vs(829. 3 ± 75. 3)U/ L,MDA:(29. 20 ± 4. 20)nmol/ mgprot,(42. 10 ± 2. 32)nmol/ mgprot vs(60. 90 ± 5. 73)nmol/ mgprot,ROS:(270. 3 ± 46. 8)U/ well,(301. 5 ± 16. 9)U/ well vs(410. 2 ± 81. 6)U/ well,all P ﹤ 0. 05], increased the cell survival and the levels of SOD activity[cell viability:0. 960 ± 0. 029,0. 906 ± 0. 039 vs 0. 822 ± 0. 058,SOD:(75. 20 ± 2. 21)U/ mgprot,(61. 20 ± 3. 38)U/ mgprot vs(49. 20 ± 5. 81)U/ mgprot,all P ﹤ 0. 05]. And IN with 350 IU/ L and 700 IU/ L increased the mRNA and protein expression of UCP2(3. 830 ± 0. 265,2. 855 ± 0. 215 vs 1. 867 ± 0. 130,0. 464 ± 0. 215,0. 355 ± 0. 006 vs 0. 288 ± 0. 018,all P ﹤ 0. 05). Compared with 70 IU/ L and 700 IU/ L IN group,350 IU/ L IN group had better results. Conclusions IN attenuates LPS - induced oxidative injury in H9c2 cells,which is probably mediated through up - regulating the expression of UCP2.
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Objective To investigate the differential expression of microRNA - 30e in sepsis - induced acute lung injury(ALI)and its correlation with interleukin(IL)- 1β and tumor necrosis factor(TNF)- α from two aspects of in vivo and in vitro. Methods Thirty SD male rats were randomly divided into 5 groups:normal control group,3 - hour sepsis group,6 - hour sepsis group,12 - hour sepsis group and 24 - hour sepsis group in equal number. Sepsis - in-duced ALI model was induced by intraperitoneal injection of lipopolysaccharide(LPS,10 mg/ kg). The rat alveolar mac-rophages NR8383 were divided into blank control group and LPS(1 mg/ L)stimulated 3,6,12,24 hour groups. Inverse transcription - polymerase chain reaction was used to assay the production changes of IL - 1β,TNF - α and miRNA - 30e in lungs and cells. The injury of lung tissue was evaluated through histopathology. Results The levels of IL - 1β and TNF - α in lung tissues of rats in sepsis groups were obviously up - regulated when compared with those in normal control groups(all P ﹤ 0. 01). The lung tissue hematoxylin - eosin staining indicated ALI in the sepsis group. The relative expression of miR - 30e in rat lung tissue in sepsis 3,6,12,24 hour groups were respectively 0. 26 ± 0. 02, 0. 41 ± 0. 08,0. 29 ± 0. 05 and 0. 18 ± 0. 05,which were significantly lower than those in normal control group(1. 23 ± 0. 24,all P ﹤ 0. 01). The levels of IL - 1β and TNF - α in LPS stimulated NR8383 cells at different time points were obviously up - regulated when compared with those in blank control groups(all P ﹤ 0. 01). The relative expression of miR - 30e in LPS stimulated 3,6,12,24 hour groups were respectively 0. 27 ± 0. 04,0. 55 ± 0. 05,0. 65 ± 0. 02 and 0. 41 ± 0. 10,which were significantly lower than those in blank control group(1. 17 ± 0. 21,all P ﹤ 0. 01). The expres-sion of miR - 30e in lung tissues of groups showed significantly negative correlations with those of IL - 1β and TNF - α(IL - 1β:r = - 0. 417,P = 0. 022;TNF - α:r = - 0. 437,P = 0. 016). The expression of miR - 30e in LPS stimulated NR8383 cells of groups also showed significantly negative correlations with those of IL - 1β and TNF - α(IL - 1β :r =- 0. 713,P = 0. 003;TNF - α:r = - 0. 712,P = 0. 002). Conclusions The expression level of miR - 30e was signifi-cantly down - regulated in sepsis - induced ALI,and had a significantly negative correlation with IL - 1β and TNF - α, which may be used as a new biomarker of diagnostic,prognosis evaluation and therapy of sepsis - induced ALI.
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Objective To investigate the protective effect of continuous intravenous infusion of Isoproterenol (ISO)on myocardial mitochondria of early septic rats and the corresponding mechanism.Methods Thirty Sprague Dawley (SD)rats were randomly divided into 5 groups (6 cases per group):control group,endotoxin group,ISO small-dose group,ISO medium-dose group and ISO large-dose group.Endotoxin group and ISO intervene group received same management apart from drug intervention:receiving intravenous injection of lipopolysaccharide (LPS)10 mg/kg followed by an continuous intravenous infusion of 9 g/L saline 1 mL/h or ISO 0.06 μg/(kg · min),0.30 μg/(kg · min)and 0.60 μg/(kg · min).Control group received intraperitoneal injection and continuous intravenous infusion with the same amount of 9 g/L saline.The primary endpoint of the study was 24 hours after injection of 9 g/L saline or LPS.Serum creatine kinase (CK) and creatine kinase isoenzyme (CK-MB),oxidative and nitrosative stress levels and swelling of isolated heart mitochondrion were detected.The pathological changes of the myocardium and morphologic changes of the heart mitochondria were observed through light microscope and scanning electron microscope,respectively.Results The levels of CK,CK-MB,nitric oxide (NO) content,inducible nitric oxide synthase (iNOS) activity and malondialdehyde (MDA)content in endotoxin group were increased compared with control group (all P ＜ 0.05),while the superoxide dismutase (SOD) activity decreased [(11.543 ± 1.080) U/mg prot vs (9.892 ±0.815) U/mg prot,P ＜0.05].The morphology of the heart mitochondria significantly changed (such as swelling,disordered arrangement,crest fracture,fusion and cavitations,and so on).ISO intervention significantly decreased the levels of CK,CK-MB and mitochondrial swelling (all P ＜ 0.05) and increased the SOD activity (all P ＜ 0.05).The levels of NO content,iNOS activity and MDA content were significantly decreased in small-dose group [(10.823 ± 2.240) μmol/g prot vs (7.917 ± 2.203) μmol/g prot,(0.045 ± 0.008) U/mg prot vs (0.033 ± 0.003) U/mg prot,(1.663 ± 0.618) mmol/mg prot vs (0.768 ± 0.312) mmol/mg prot,all P ＜ 0.05],while the levels of iNOS activity and MDA content were significantly increased in medium-and large-dose group (all P ＜ 0.05) ; compared with medium-dose group,the degree of mitochondrial swelling in large-dose group increased (1.160 ± 0.186 vs 1.393 ± 0.128,P ＜ 0.05).The pathological changes of the myocardium mitochondria significantly improved.Conclusions The myocardium and myocardial mitochondria of early septic rats were damaged,continuous intravenous infusion of low-dose ISO revealed protective effect on these damages,and the corresponding mechanism may relate to the decrease of the oxidative and nitrosative stress.
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Sepsis-associated encephalopathy is a diffuse brain dysfunction that occurs secondary to infection.It is characterized by alteration of consciousness and cognition,seizure or focal neurological signs.Sepsis-associated encephalopathy is accompanied by abnormalities of electroencephalogram and somatosensoryevoked potentials,increased biomarkers of brain injury and,frequently,by neuroradiological abnormalities.Its diagnosis relies essentially on neurologic examination.Hepatic/uremic encephalopathy,metabolic disturbances,drug overdose,withdrawal syndrome and Wernicke's encephalopathy are the main differential diagnosis of sepsis-associated encephalopathy.Currently,treatment consists mainly of controlling sepsis.Various drugs acting on septic pathophysiology have been tested in septic animals.