A preliminary study of long-term mitochondrial dysfunction in rat brain caused by lipopolysaccharide-induced sepsis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To preliminarily investigate the long-term structural and functional injuries of mitochondria in rat brain caused by sepsis.</p><p><b>METHODS</b>Wistar rats were randomly assigned into sepsis and control groups. A rat model of sepsis was prepared by an intraperitoneal injection of 10 mg/kg lipopolysaccharide (LPS) of gram-negative bacteria, and the survival assay was performed. Eight rats in the sepsis group were sacrificed at 12, 24, 48, or 72 hours after LPS injection, while rats in the control group were sacrificed after an intraperitoneal injection of an equal volume of normal saline. Mitochondria were extracted from rat brain tissue. Mitochondrial membrane potential (MMP) and mitochondrial swelling level were determined by flow cytometry, and the activities of electron transport chain complexes (I-V) were measured using enzyme assay kits. Hematoxylin-eosin (HE) staining and electron microscopy were used to observe morphological changes in brain tissue and mitochondria.</p><p><b>RESULTS</b>The sepsis group had a significantly lower survival rate than the control group (P<0.01). The MMP and activities of electron transport chain complexes (I-V) in the sepsis group, which were significantly lower than those in the control group (P<0.05), were reduced to the lowest levels at 48 hours and partially recovered at 72 hours. The mitochondrial swelling level in the sepsis group, which was significantly higher than that in the control group (P<0.05), increased to the peak level at 48 hours and partially recovered at 72 hours. Hematoxylin and Eosin staining revealed substantial damages in the structure of brain tissue, and electron microscopy showed mitochondrial swelling, and vacuolization in a few mitochondria.</p><p><b>CONCLUSIONS</b>In the rat model of LPS-induced sepsis, both structural and functional injuries are found in cerebral mitochondria, and achieve the peak levels probably at around 48 hours.</p>

Expression pattern changes of microRNA in the lung tissue of mice with acute lung injury induced by lipopolysaccharide / 中华实用儿科临床杂志

Objective To investigate the change of expression pattern of microRNA in the lung with acute lung injury (ALI)/acute respiratory distress syndrome(ARDS) induced by lipopolysaccharide (LPS),and to provide an evidence that microRNAs are involved in the pathogenesis of ALI/ARDS.Methods Twenty-four C57BL mice were randomly divided into control group and LPS treated group,12 mice in each group.The rats in LPS treated group were treated with intratracheal injection of LPS at a dose of 10 mg/kg body weight into the lung.The rats in control group were treated with the same dose of saline instead.All mice were sacrificed 24 hours after operation,the left lung was excised to measure the wet-to-dry weight (W/D) ratio,and the right upper lobe was stained with hematoxylin and eosin (HE).A microRNA microarray chip was used to profile miRNA expressions in the lung of rats in both LPS treated group and control group.Online software packages were used to predict the gene targeted by microRNAs.Results Compared with the control group,the LPS treated mice had obvious respiratory symptoms,the W/D ratio was significantly increased (P ＜ 0.01),and the pathology was characterized with ALI/ARDS.The microarray chip results demonstrated that the expressions of 48 microRNAs were significantly changed in the ALI/ARDS mice.Among these miRNA,27 cases were up-regulated,21 cases were down-regulated.The target genes of these microRNAs might be involved in regulating the signal pathway of inflammation.Conclusions Some miRNAs express differently in the model of ALI/ARDS,and they may play an important role in pathophysiological process of ALI/ARDS.

Incidence and risk factor analysis of neonatal apnea in the representative regions of Guangdong Province / 南方医科大学学报

<p><b>OBJECTIVE</b>To conduct an epidemiological survey of the prevalence of neonatal apnoea and and identify its risk factors in Guangdong Province.</p><p><b>METHODS</b>The epidemiological data of neonatal apnea were collected by means of cluster sampling from 10 representative regions of Guangdong Province, and the risk factors for this condition were analyzed with logistic regression.</p><p><b>RESULTS</b>In the representative regions chosen for this survey, the incidence of neonatal apnea was 9.85% in the newborn infants, suggesting a generally similar picture of its prevalence in Guangdong Province. Maternal heart disease and anaemia, number of miscarriages, fetal position and present, oxytocin application, vacuum extraction, prolonged second stage of labor, and number of cesarean delivery were identified as the risk factors for neonatal apnoea, whereas number of pregnancies, the last antenatal examination prior to delivery, high-level antenatal examination hospital, antenatal examination times, and number of normal deliveries were the protective factors. Abnormal amniotic fluid, premature birth, and cord around the neck were the most important risk factors for neonatal apnoea, and adequate amniotic fluid volume is the protective factors for neonatal apnoea.</p><p><b>CONCLUSION</b>Rigorous control of the risk factors and enhancement of the protective factors can reduce or even prevent the incidence of neonatal apnoea.</p>

Detection of angiotensin II in the maternal-fetal interface in pregnancy-induced hypertension / 南方医科大学学报

<p><b>OBJECTIVE</b>To detect angiotensin II (ANG II) in the maternal blood, umbilical cord blood, and at the maternal-fetal interface in women with pregnancy-induced hypertension (PIH) and explore the etiology of PIH and pathophysiologic mechanism of intrauterine growth restriction (IUGR).</p><p><b>METHODS</b>Enzyme-linked immunosorbent assay (ELISA) was used to detect the concentration of ANG II in the maternal blood, cord blood, and maternal and fetal placental tissues in 30 women with PIH and 30 with normal pregnancy, and the results were analyzed with independent-sample t test and Pearson correlation analysis.</p><p><b>RESULTS</b>ANG II level in the maternal placental tissue homogenate showed no significant difference between women with PIH and normal pregnant women (8.51+/- 4.01 vs 7.76+/-3.47 pg/ml, P>0.05), but women with PIH had significantly higher ANG II in the fetal placental tissue (11.82+/-3.92 vs 9.64+/-2.63 pg/ml, P<0.05). ANG II level was significantly higher in the maternal blood of women with PIH than in normal pregnant women (46.44+/-8.48 vs 32.43+/-5.87 pg/ml, P<0.001), but similar in the cord blood (68.83+/-8.68 vs 72.47+/-8.51 pg/ml; P>0.05). A positive correlation was indicated between the cord blood and maternal peripheral blood ANG II levels in women with PIH (r=0.7379, P<0.05).</p><p><b>CONCLUSION</b>ANG II in the fetal placental tissue is elevated, and the cord blood and maternal peripheral blood ANG II levels are positively correlated in women with PIH.</p>

Continuous blood purification in the treatment of pediatric septic shock / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the efficacy of continuous blood purification (CBP) and to explore its mechanism in the treatment of pediatric septic shock.</p><p><b>METHODS</b>Nine children weighted 3.1 kg - 14.0 kg with septic shock were treated with continuous veno-venous hemofiltration (CVVH) which is also referred to as CBP with blood access of double-lumen hemodialysis catheter of 6.5 to 8Fr inserted via central vein, hemofilters of Minifilter plus (for children with body weight < 5 kg) or AV400s (for children with body weight > or = 5 kg), child's type extracorporeal circuit vessel and heparin anticoagulation. The replacement solution was delivered pre-dilution after 3 to 4 hours' post-dilution. The blood gas, clinical biochemical items, medium molecule substance (MMS) concentration in blood as well as capillary refill time (CRT), BP, urine output, vasopressors dosage were examined at a set of time points from the beginning to the end of the CVVH.</p><p><b>RESULTS</b>Of the 9 children, 6 had acute renal failure (ARF), 3 had acute respiratory distress syndrome (ARDS), 5 were blood culture positive and all the 9 needed vasopressors to keep BP before CVVH. The blood pH was 7.14 +/- 0.23, base excess (BE) was -11.3 +/- 4.25 mmol/L, MMS was 3532 +/- 519 U/L, PO2/FiO2 was 188 +/- 33, CRT > 5 s, urine output was 0.85 +/- 0.52 ml/(kg.hr) and the adrenalin dosage 1.36 +/- 0.48 microg/(kg.min), and dopamine 16.35 +/- 3.27 microg/(kg.min) before CVVH. The patients' condition was improved much as demonstrated by pH 7.38 +/- 0.16, BE -0.28 +/- 1.37 mmol/L, MMS 2576 +/- 375 U/L, PO2/FiO2 285 +/- 63, CRT < 2 s, and the adrenalin dosage 0.08 +/- 0.04 microg/(kg.min) and dopamine 8.53 +/- 6.72 microg/(kg.min), urine output 2.9 +/- 1.6 ml/(kg.hr) after 24 hour treatment with CVVH. Of the 9 children, 2 died of MODS (1 intussusception complicated with intestine necrosis, 1 severe scald) and 1 was given up because of severe intestinal fistula, the other 6 children recovered at the end.</p><p><b>CONCLUSION</b>CBP was effective in treatment of pediatric septic shock by improving the oxygenation, correcting metabolic acidosis, stabilizing BP, increasing the tissue perfusion and eliminating the medium molecule substances.</p>