Value of Pediatric Early Warning Score in identifying the condition of critically ill children / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To study the value of Pediatric Early Warning Score (PEWS) in identifying the condition of critically ill children.</p><p><b>METHODS</b>A total of 120 children who were transferred to the pediatric intensive care unit (PICU) from the general ward during hospitalization or admitted to the PICU after emergency treatment in the Xiangya Hospital of Central South University from January to December, 2016 were enrolled as the PICU group. The other 120 children who were admitted to the general ward in the hospital were used as the control group. According to the disease type, the PICU group was further divided into two subgroups: respiratory/circulatory system diseases (n=55) and nervous/other system diseases (n=65). The PEWS score on admission was recorded, and the receiver operating characteristic (ROC) curve was used to analyze the value of PEWS in evaluating patients' condition.</p><p><b>RESULTS</b>The PICU group had a significantly higher PEWS score than the control group (P<0.05). The respiratory/circulatory system disease subgroup had a significantly higher PEWS score than the nervous/other system disease subgroup (P<0.05). In predicting whether the child was admitted to the PICU, PEWS had a sensitivity of 85%, a specificity of 95%, and an area under the ROC curve (AUC) of 0.951 (95% confidence interval: 0.923-0.980) at the optimal cut-off value of 3.5 (PEWS score). The AUC of PEWS was 0.768 in the nervous/other system disease subgroup and 0.968 in the respiratory/circulatory system disease subgroup. The mortality rate of children with a PEWS score of >6, 4-6 and ≤3 was 40%, 21% and 0 respectively (P<0.001).</p><p><b>CONCLUSIONS</b>PEWS can well identify disease severity in critically ill children, and it has different sensitivities in children with different varieties of diseases. PEWS has a good value in predicting children's prognosis.</p>

Regulation of rat airway smooth muscle cell proliferation by mitochondrial ATP-sensitive K(+) channel in asthmic rats / 生理学报

The objective of this paper was to investigate the effect and mechanism of mitochondrial ATP-sensitive K(+) (MitoK(ATP)) channel on the proliferation of airway smooth muscle cells (ASMCs) in asthmic rats. Thirty-six Sprague-Dawley (SD) rats were randomly assigned into 2 groups (18 in each): (1) Asthma group: the asthmic rat model was established by ovalbumin (OVA) sensitization and excitation; (2) Normal group: rats were subjected to inhalation of equal amount of normal saline. The rat ASMCs were isolated from fresh lung tissues and cultured respectively as follows: (1) CONTROL GROUP: normal ASMCs were cultured under normoxia for 24 h; (2) Diazoxide group: normal ASMCs were cultured under normoxia for 24 h with diazoxide (an opener of MitoK(ATP) channel); (3) 5-HD group: normal ASMCs were cultured under normoxia for 24 h with 5-hydroxydecanoate (5-HD) (an antagonist of MitoK(ATP) channel); (4) Asthma group: Asthmic ASMCs were cultured under normoxia for 24 h; (5) Asthma + diazoxide group: Asthmic ASMCs were cultured under normoxia with diazoxide for 24 h; (6) Asthma + 5-HD group: Asthmic ASMCs were cultured under normoxia with 5-HD for 24 h. The mitochondrial membrane potential (ΔΨm) was detected using Rhodamine 123 (R-123). The level of reactive oxygen species (ROS) was detected by DCF fluorescence. The expression of nuclear factor-kappa B (NF-κB) mRNA was examined by RT-PCR. The proliferation and apoptosis of rat ASMCs were examined respectively by MTT colorimetric assay and cell cycle analysis. The results were as follows. (1) After exposure to diazoxide for 24 h, the R-123 fluorescence intensity, the ROS level, NF-κB mRNA expression and the MTT absorbance value (A value) in normal ASMCs were significantly increased, and the apoptosis of rat ASMCs was significantly decreased compared to the control group (P<0.05). However, there was no significant changes in those indices after the normal ASMCs had been exposed to 5-HD for 24 h. (2) In Asthma and Asthma + diazoxide groups, the R-123 fluorescence intensity, ROS level and the MTT A value were markedly increased, and the apoptosis was markedly decreased compared to control group (P<0.05). These changes were more obvious in Asthma + diazoxide group than those in Asthma group (P<0.05). 5-HD partly weakened the effect of asthma on the R-123 fluorescence intensity, ROS level and the MTT A value and the apoptosis of rat ASMCs (P<0.05). R-123 fluorescence intensity and NF-κB mRNA expression were positively correlated with ROS level. NF-κB mRNA expression was positively correlated with the MTT A value and negatively correlated with the apoptosis of rat ASMCs. All the results suggest that the opening of MitoK(ATP) channel followed by a depolarization of ΔΨm contributes to the increase in ROS level and NF-κB mRNA expression in rat ASMCs and to the unbalance between cell proliferation and apoptosis of ASMCs induced by asthma. This might be a mechanism of the development of airway remodeling in asthma.

Effect of opening of mitochondrial ATP-sensitive K(+) channels on the expression of hypoxia inducible factor-1alpha and cell proliferation in pulmonary arterial smooth muscle cells of rats / 生理学报

The objective of this paper was to investigate the effect of mitochondrial ATP-sensitive K(+) (MitoK(ATP)) channels on the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and cell proliferation in pulmonary arterial smooth muscle cells (PASMCs) of rats. Cultured PASMCs were divided into six groups as follows: (1) normoxia group: cultured under normoxia for 24 h; (2) normoxia + diazoxide group: cultured under normoxia with diazoxide, an opener of MitoK(ATP) channel, for 24 h; (3) normoxia + 5-HD group: cultured under normoxia with 5-hydroxydecanoate (5-HD), an antagonist of MitoK(ATP) channel, for 24 h; (4) hypoxia group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) for 24 h; (5) hypoxia + diazoxide group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) with diazoxide for 24 h; (6) hypoxia + 5-HD group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) with 5-HD for 24 h. The relative changes in mitochondrial potential were tested with Rhodamine 123 (R-123) fluorescence technique. Immunohistochemical method was used to trace the expression of HIF-1alpha. The proliferation of PASMCs was examined by MTT colorimetric assay. The results were as follows: The intensity of R-123 fluorescence in normoxia + diazoxide group was significantly increased as compared with that in normoxia group (P<0.05), and the intensity of R-123 fluorescence in hypoxia + diazoxide group was also significantly increased as compared with that in hypoxia group (P<0.05). 24-hour hypoxia or 24-hour hypoxia + diazoxide markedly increased the intensity of R-123 fluorescence in PASMCs as compared with normoxia (P<0.05), and the change was more prominant in hypoxia + diazoxide group than that in hypoxia group (P<0.05). There was no significant difference in the intensity of R-123 fluorescence between normoxia group and normoxia + 5-HD group (P>0.05). However, 5-HD weakened the effect of 24-hour hypoxia on the intensity of R-123 fluorescence. The intensity of R-123 fluorescence in hypoxia + 5-HD group was significantly decreased as compared with that in hypoxia group (P<0.05). After exposure to hypoxia or hypoxia + diazoxide for 24 h, the expression of HIF-1alpha and the proliferation of PASMCs were significantly increased as compared with that in normoxia or normoxia + diazoxide group (P<0.05), and the change was more significant in hypoxia + diazoxide group than that in hypoxia group (P<0.05). There was no significant difference in the expression of HIF-1alpha and the proliferation of PASMCs between normoxia group and normoxia + 5-HD group (P>0.05). However, the expression of HIF-1alpha and the proliferation of PASMCs in hypoxia + 5-HD group were significantly decreased as compared with that in hypoxia group (P<0.05). All these results suggest that the opening of MitoK(ATP) channels followed by a depolarization of mitochondrial membrane might contribute to the increase of the expression of HIF-1alpha and the proliferation of PASMCs. This might be a mechanism of the development of hypoxic pulmonary hypertension.

The relationships among reactive oxygen species, hypoxia-inducible factor 1alpha and cell proliferation in rat pulmonary arterial smooth muscle cells under hypoxia / 生理学报

The objectives of this paper were to observe the changes of reactive oxygen species (ROS) in rat pulmonary arterial smooth muscle cells (PASMCs) under hypoxic condition and to test if hypoxia-induced proliferation of PASMCs was mediated by ROS. PASMCs were divided into three groups: normal group, hypoxia group and hypoxia + Mn-TBAP (a ROS scavenger) group. The level of ROS was determined by a laser scanning confocal microscope. The expression of hypoxia-inducible factor 1alpha (HIF-1alpha) mRNA was detected by semi-quantitative reverse transcription PCR (RT-PCR). HIF-1alpha protein was detected using immunohistochemical staining, and the proliferation of PASMCs was examined by MTT colorimetric assay. The results were as follows: (1) The level of ROS in hypoxia group was significantly increased as compared with that in the normal group (P<0.05). The level of ROS in hypoxia + Mn-TBAP group was significantly decreased as compared with that in hypoxia group (P<0.05), but was increased as compared with that in the normal group (P<0.05). (2) The expressions of HIF-1alpha mRNA and protein in hypoxia group and hypoxia + Mn-TBAP group were increased as compared with those in the normal group (P<0.05), and these changes were more significant in hypoxia group than those in hypoxia + Mn-TBAP group. (3) The proliferation of PASMCs in hypoxia group was more obvious than that in the normal group and hypoxia + Mn-TBAP group (P<0.05), and the proliferation of PASMCs in hypoxia + Mn-TBAP group was increased more significantly than that in the normal group (P<0.05). The results indicate that ROS is significantly increased in rat PASMCs under hypoxia, and that ROS affects the expression of HIF-1alpha and the proliferation of PASMCs under hypoxia. Therefore, ROS may play an important role in the pathogenesis of pulmonary hypertension and hypoxic signal transductions.

Effect of opening of mitochondrial ATP-sensitive K⁺ channel on the distribution of cytochrome C and on proliferation of human pulmonary arterial smooth muscle cells in hypoxia / 生理学报

The objective of this paper was to investigate the contribution of mitochondrial ATP-sensitive K+ channel (mitoK(ATP)) and mitochondrial membrane potential (Deltapsim) to the distribution of cytochrome C in human pulmonary arterial smooth muscle cells (HPASMCs) and to the proliferation of HPASMCs induced by hypoxia. HPASMCs were divided into 6 groups, as following: (1) control group: cultured under normoxia; (2) diazoxide group: cultured in normoxia with diazoxide, an opener of mitoK(ATP); (3) 5-HD group: cultured in normoxia with 5-hydroxydecanoate (5-HD), an antagonist of mitoK(ATP); (4) 24-hour hypoxia group: cultured in hypoxia for 24 h; (5) 24-hour hypoxia + diazoxide group: cultured in hypoxia with diazoxide for 24 h; (6) 24-hour hypoxia + 5-HD group: cultured in hypoxia with 5-HD for 24 h. The relative changes in mitochondrial potential were tested with rhodamine fluorescence (R-123) technique. Western blot was used to detect the expression of cytochrome C protein in cell plasma and mitochondria,respectively. The expression of cell caspase-9 protein was determined with Western blot. The proliferation of HPASMCs was examined by cell cycle analysis and MTT colorimetric assay. The results were as following: after exposure to diazoxide for 24 h, the intensity of R-123 fluorescence in normoxic HPASMCs was significantly increased compared with that in the control group (P<0.05), but there was no significant change of the intensity of R-123 fluorescence after the HPASMCs had been exposed to 5-HD for 24 h; 24-hour hypoxia or 24-hour hypoxia + diazoxide could markedly increase the intensity of R-123 fluorescence in HPASMCs compared with normoxia (P<0.05), and the change was more significant in 24-hour hypoxia + diazoxide group than that in 24-hour hypoxia group (P<0.05); 5-HD could weaken the effect of 24-hour hypoxia on the intensity of R-123 fluorescence. After exposure to diazoxide for 24 h, the ratio of the expression of cytosolic cytochrome C protein to that of mitochondrial cytochrome C protein was significantly decreased compared with that in the control group (P<0.05), and the expression of caspase-9 protein was significantly decreased compared with that in the control group (P<0.05). The percentage of S phase and A value of MTT were significantly increased compared with those in the control group (P<0.05). But there were no significant changes in these tests after HPASMCs had been exposed to 5-HD for 24 h (P>0.05). After exposure to hypoxia or hypoxia + diazoxide for 24 h, the ratio of the expression of cytosolic cytochrome C protein to that of mitochondrial cytochrome C protein and the expression of caspase-9 protein were significantly decreased compared with those in the control group (P<0.05). The percentage of S phase and A value of MTT were significantly increased compared with those in the control group (P<0.05). These changes were more significant in 24-hour hypoxia + diazoxide group than those in 24-hour hypoxia group (P<0.05). 5-HD could weaken the effect of hypoxia on the changes of the distribution of cytochrome C, the expression of caspase-9 in HPASMCs and the proliferation of HPASMCs induced by hypoxia (P<0.05). All these results suggest that the opening of mitoK(ATP) followed by a depolarization of Deltapsim induced by hypoxia might contribute to the inhibition of the release of cytochrome C from mitochondria to plasma in HPASMCs. This might be a mechanism of the development of hypoxic pulmonary hypertension. The signal transduction pathway of mitochondria might play an important role in the relationship between Deltapsim and apoptosis of HPASMCs.