Effect of ulinastatin on serum levels of tumor necrosis factor-α, P-selectin, and thrombin-antithrombin complex in young rats with sepsis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of ulinastatin (UTI) for early drug intervention on the serum levels of tumor necrosis factor-α (TNF-α), P-selectin, and thrombin-antithrombin complex (TAT) in young rats with sepsis.</p><p><b>METHODS</b>A total of 120 male rats aged 4 weeks were randomly divided into normal control group, sham-operation group, sepsis group, low-dose UTI group (50 000 U/kg), and high-dose UTI group (200 000 U/kg), with 24 rats in each group. Modified cecal ligation and puncture was performed to establish a rat model of sepsis, and the rats in the low- and high-dose UTI groups were given caudal vein injection of UTI after model establishment. ELISA was used to measure the serum levels of TNF-α, P-selectin, and TAT at 6, 12, and 24 hours after model establishment.</p><p><b>RESULTS</b>The sepsis group had significant increases in the serum levels of TNF-α, P-selectin, and TAT at 6 hours, and the serum levels of TNF-α and TAT continued to increase by 24 hours (P<0.05); P-selectin reached the peak at 12 hours and decreased slightly at 24 hours (P<0.05). The UTI groups had similar change patterns in the levels of P-selectin and TAT as the sepsis group. The UTI groups had significant increases in the level of TNF-α at 6 hours, but gradually decreased over time. The changes in serum levels of TNF-α, P-selectin, and TAT in the UTI groups were significantly smaller than in the sepsis group (P<0.05). The high-dose UTI group had significantly smaller changes in serum levels of TNF-α, P-selectin, and TAT than the low-dose UTI group (P<0.05).</p><p><b>CONCLUSIONS</b>Early intervention with UTI can significantly improve coagulation function and inhibit the production of TNF-α, P-selectin, and TAT in young rats with sepsis. High-dose UTI has a significantly greater effect than low-dose UTI.</p>

Effect of leptin on expression of calpain-1 and Bcl-2 and apoptosis in myocardial tissue of neonatal rats after asphyxia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effect of leptin on the expression of calcium-activated neutral protease 1 (calpain-1) and B cell lymphoma-2 (Bcl-2) and apoptosis in the myocardial tissue of neonatal rats after asphyxia.</p><p><b>METHODS</b>A total of 48 neonatal rats were randomly and equally divided into normal control group, asphyxia group, leptin treatment groups, and calpain-1 inhibitor (CAI-1) group. The neonatal rat model of asphyxia under normal atmospheric condition was established in all groups except the control group. For the leptin treatment groups, rats received 20, 80, and 160 μg/kg leptin by intraperitoneal injection immediately after model establishment, respectively. For the CAI-1 group, rats received 10 mg/kg CAI-1 by intraperitoneal injection immediately after model establishment. For all the groups, the myocardial tissue was collected at 2 hours after model establishment. Immunohistochemistry was used to measure the expression of calpain-1 and Bcl-2. The TUNEL method was used to evaluate apoptosis of myocardial cells.</p><p><b>RESULTS</b>The expression of calpain-1 and Bcl-2 and apoptosis index (AI) were significantly higher in the asphyxia group than in the normal control group (P˂0.05). The leptin treatment groups and the CAI-1 group had significantly lower expression of calpain-1, significantly lower AI, and significantly higher expression of Bcl-2 than the asphyxia group (P˂0.05). The CAI-1 group had the largest changes in all the indices compared with the asphyxia group. However, there were no significant differences in all indices between the 160 μg/kg leptin treatment group and the CAI-1 group. After asphyxia, the expression of calpain-1 was positively correlated with AI, while the expression of Bcl-2 was negatively correlated with AI and the expression of calpain-1 (P˂0.05).</p><p><b>CONCLUSIONS</b>Leptin reduces apoptosis of myocardial cells in asphyxiated neonatal rats by the inhibition of calpain-1 activation and upregulation of Bcl-2 expression.</p>

Effects of erythropoietin on cardiomyocyte apoptosis and endoplasmic reticulum stress-related proteins in neonatal rats with asphyxia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the effects of erythropoietin (EPO) on cardiomyocyte apoptosis and endoplasmic reticulum stress (ERS)-related proteins, glucose-regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP), in neonatal rats with asphyxia.</p><p><b>METHODS</b>A total of 120 newborn Sprague-Dawley rats (7 days old) were randomly divided into sham-operated (n=40), asphyxia (n=40) and EPO-treated asphyxia groups (n=40). A neonatal rat model of normobaric asphyxia was established in the asphyxia and EPO-treated asphyxia groups. The rats in the EPO-treated asphyxia group received intraperitoneal injection of recombinant human erythropoietin (500 U/mL) immediately after the model was established, while the other two groups received the same volume of normal saline (0.9%). Heart blood and myocardial tissue samples were collected from 8 rats in each group at 2, 6, 12, 24 or 48 hours after the model was established. Serum creatine kinase (CK) and lactate dehydrogenase (LDH) levels were measured; cardiomyocyte apoptosis was evaluated, and expression of myocardial GRP78 and CHOP was measured.</p><p><b>RESULTS</b>Compared with the sham-operated and EPO-treated asphyxia groups, the asphyxia group had significantly increased serum CK and LDH levels, number of apoptotic cells, and expression of myocardial GRP78 and CHOP at each time point (P<0.01), and all the indices were significantly higher in the EPO-treated asphyxia group than in the sham-operated group (P<0.01). At 24 hours after asphyxia, the expression of myocardial CHOP was positively correlated with the myocardial apoptosis index (r=0.944, P<0.01).</p><p><b>CONCLUSIONS</b>EPO exerts a protective effect on the myocardium of neonatal rats with hypoxic-ischemic injury by regulating ERS-related proteins GRP78 and CHOP and reducing cardiomyocyte apoptosis.</p>

Comparing the effect of high frequency oscillatory ventilation and conventional mandatory ventilation on the myocardial function of rabbit with inhalation injury / 中华烧伤杂志

<p><b>OBJECTIVE</b>To compare the effect of high frequency oscillatory ventilation (HFOV) and conventional mandatory ventilation (CMV) on the myocardial function of rabbits with inhalation injury.</p><p><b>METHODS</b>Steam inhalation injury model was reproduced in 16 New Zealand albino rabbits. They were randomly divided into CMV group (n = 8) and HFOV group (n = 8) by drawing lots, and they received ventilation in metered volume and HFOV treatment respectively. Heart blood was drawn from rabbits before they were sacrificed 4 hours after treatment to determine the plasma activity of lactate dehydrogenase 1 (LDH1) and creatine phosphorylated kinase (CPK-MB). Myocardial tissue from left ventricle was harvested and homogenized to determine the concentration of TNF-α and IL-8, the activity of caspase-1, and the activity of myosin-light-chain kinase (MLCK) and the ATPase of myosin light chain (MLC-ATPase) by enzyme-linked immunosorbent assay, spectrophotometry, and the nuclide liquid scintillation technique respectively. Part of the myocardial tissue sample was examined pathologically. Data were processed with analysis of variance.</p><p><b>RESULTS</b>(1) The activities of LDH1 and CPK-MB in plasma were obviously higher in CMV group than in HFOV group [(643 ± 108), (342 ± 48) U vs. (233 ± 92), (186 ± 36) U, with F value respectively 10.326 and 9.846, P values all below 0.01]. (2) The contents of TNF-α, IL-8 and the activity of caspase-1 in myocardial tissue homogenate were obviously higher in CMV group than in HFOV group [(181 ± 35), (89 ± 19) pg/g, and (0.56 ± 0.27) g/g protein vs. (94 ± 21), (43 ± 11) pg/g, and (0.24 ± 0.12) g/g protein, with F value respectively 8.239, 7.826, 5.716, P values all below 0.01]. (3) The activities of MLC-ATPase and MLCK were lower in CMV group than in HFOV group [(0.24 ± 0.12) µmol×mg(-1)×min(-1), (3.3 ± 1.1) mmol×mg(-1)×min(-1) vs. (0.48 ± 0.16) µmol×mg(-1)×min(-1), (7.7 ± 1.7) mmol×mg(-1)×min(-1), with F value respectively 4.125, 4.766, P values all below 0.01]. (4) No obvious necrosis, degeneration or inflammatory cell infiltration was observed in myocardial tissue of rabbits in 2 groups under light microscope; but the myocardial fiber was slightly swollen, and it was less marked in the HFOV group.</p><p><b>CONCLUSIONS</b>The influence of HFOV on myocardial myosin phosphorylation system of rabbits with inhalation injury is less than that of CMV.</p>

Effects of high frequency oscillatory ventilation and its combination with pulmonary surfactant treatment on inflammatory response in rabbit lung with inhalation injury / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate the effects of high frequency oscillatory ventilation (HFOV) and its combination with administration of pulmonary surfactant (PS) on inflammatory response of lung tissue in rabbits with inhalation injury.</p><p><b>METHODS</b>Severe steam inhalation injury models were reproduced in 24 New Zealand albino rabbits. They were divided into control group (n = 8), HFOV group (n = 8), and HFOV + PS group (n = 8) according to the random number table, and they received ventilation in metered volume, HFOV, and HFOV + PS treatment respectively. Lung tissue samples of rabbits were collected at 3.5 h after treatment for pathological inspection and pulmonary injury score, assay of the activity of myeloperoxidase (MPO) and cysteinyl aspartate-specific protease 1 (caspase-1), and the determination of the contents of TNF-alpha, IL-18, IL-10, IL-13 and their mRNA expression.</p><p><b>RESULTS</b>Pathological change in different degree of rabbit lung tissue in each group were observed, and they were most obvious in the control group, and least in the HFOV + PS group. The lung tissue injury scores of control group, HFOV group, and HFOV + PS group was 3.71 +/- 0.43, 2.87 +/- 0.26, and 2.08 +/- 0.28 respectively. The difference between either two of them were statistically significant (P < 0.01). The MPO content and caspase-1 activity of rabbits in HFOV and HFOV + PS groups were obviously lower than those in control group (P < 0.01), and MPO content and caspase-1 activity of rabbits in HFOV + PS group were obviously lower than those in HFOV group (P < 0.05). In HFOV group and HFOV + PS group, the contents of TNF-alpha, IL-18 and their mRNA expression in lung tissue homogenates were obviously lower than those in control group (P < 0.01); while the contents of IL-10, IL-13 and their mRNA expression were obviously higher than those in control group (P < 0.01). Changes in these contents and expression in HFOV + PS group were more obvious than those in HFOV group (P < 0.05).</p><p><b>CONCLUSIONS</b>HFOV can alleviate inflammatory response in rabbit lung tissue and pulmonary injury induced by inhalation injury, and the effect is more obvious when combined with PS.</p>

Effect of Xinmailong on hypoxia-inducible factor-1alpha expression in neonatal rats with asphyxia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Xinmailong, a compound extracted from Periplaneta americana, is used for the treatment of cardiovascular diseases. This study investigated the effects of Xinmailong on myocardial hypoxia-inducible factor-1alpha (HIF-1alpha) and plasma endothelin-1(ET-1) levels in neonatal rats with asphyxia and explored the protection mechanism of Xinmailong in hypoxia-ischemic myocardial injury.</p><p><b>METHODS</b>Seven-day-old Sprague-Dawley rats were randomly divided into three groups (n=30 each): sham-operated, asphyxia, Xinmailong-treated asphyxia. Each group was randomly subdivided into three groups according to the observed time points: 6 hrs, 24 hrs and 72 hrs. Xinmailong (5 mg/kg) was intraperitoneally injected to the rats in the Xinmailong-treated group five minutes before asphyxia. Myocardial HIF-1alpha expression, and plasma ET-1 and creatine kinase (CK) levels were measured. The histopathologic changes of the myocardium were observed by hematoxylin-eosin staining.</p><p><b>RESULTS</b>Four rats died in the asphyxia group while only one died in the Xinmailong-treated group during the experiment. The plasma ET-1 and CK levels as well as myocardial HIF-1alpha expression increased at 6 hrs, reached a peak at 24 hrs, and declined at 72 hrs after asphyxia in the asphyxia group, being higher than that in the sham-operated group (P<0.01). Myocardial ischemia was observed in the three time points, and cell necrosis occurred at 24 hrs after asphyxia in the asphyxia group. Myocardial HIF-1alpha expression was positively correlated with plasma ET-1 levels (r=0.876, P<0.01). In the Xinmailong-treated group, plasma levels of CK and ET-1 as well as myocardial HIF-1alpha expression were significantly lower than those in the asphyxia group (P<0.01). Myocardial ischemia was alleviated and no cell necrosis was found in the Xinmailong-treated group.</p><p><b>CONCLUSIONS</b>Asphyxia leads to increase in myocardial HIF-1alpha expression and plasma levels of ET-1 and CK. Xinmailong can reduce the myocardial expression of HIF-1alpha and decrease plasma ET-1 levels, thus alleviating hypoxia-ischemic myocardial injury.</p>

Etiology and high risk factors of neonatal ventilator-associated pneumonia / 中国当代儿科杂志

<p><b>OBJECTIVE</b>Ventilator-associated pneumonia (VAP) is a common nosocomial infection and is responsible for a very high mortality in neonatal intensive care unit (NICU) patients. This study was designed to investigate the etiology and high risk factors of neonatal VAP.</p><p><b>METHODS</b>The clinical data of 106 critical neonates who were treated with mechanical ventilator between 2003 and 2005 were studied retrospectively.</p><p><b>RESULTS</b>Of the 106 neonates, 84 received mechanical ventilation for > or = 48 hrs. Thirty-five (41.7%) out of the 84 patients developed VAP. Univariate analysis showed that gestational age, duration of mechanical ventilation, reintubation, birth weights, primary lung disease and gamma globulin administration were associated with the development of VAP (P < 0.05). Multivariate stepwise logistic regression analysis showed that primary lung disease (OR=3.671, 95% CI=1.0-13.45, P < 0.05), duration of mechanical ventilation (OR=4.945, CI=1.51-16.21, P < 0.01), reintubation (OR=7.721, 95% CI=2.31-25.85, P < 0.01) and high-dose gamma globulin administration (OR=5.520, 95%CI=2.08-16.26, P < 0.01) were predicted factors for the development of VAP. The detection rate of gram negative bacilli (76.9%) was the highest, followed by gram positive coccus (17.9%) in VAP patients.</p><p><b>CONCLUSIONS</b>Opportunistic drug-resistant bacteria are common pathogens for neonatal VAP. The risk of VAP is multifactorial, including external medical environments and patients' internal agents.</p>