Risk factors for the failure of INSURE strategy in very and extremely low birth weight preterm infants / 中国新生儿科杂志

Objective To study the risk factors for failure of INSURE strategy in very and extremely low birth weight preterm (V/ELBW) infants.Method From January 2005 to December 2014,clinical data of 149 preterm infants (gestational age less than 32 weeks) admitted to neonatal department of Tongji Hospital who received intubation-surfactant-extubation (INSURE) strategy were collected.These infants were assigned into two groups:INSURE failure group and INSURE success group,according to whether a second dose of surfactant or mechanical ventilation was needed within 72 hours after first pulmonary surfactant treatment.The clinical characteristics and outcomes between the two groups were compared.Chi square and t tests were used to define the differences between groups.Logistic regression analysis was used to identify the independent risk factors for INSURE failure.Result Among the 1 149 patients,148 received INSURE treatment,and 113 cases (76.4％) were successfully treated with the INSURE strategy.The infants in the failure group were statistically lower in birth weight,gestation age,antenatal steroids utilization rate,PaO2 and PaO2/FiO2 than those in the success group,while the age of mother,male/female ratio and PaCO2 were higher in the failure group.Logistic regression analysis showed that male (OR =7.440,95％ CI 1.846 ～29.984),BW ＜ 1 000 g (OR =9.180,95％ CI 1.716 ～49.105),PaCO2 ＞48 mmHg (OR =5.996,95％ CI 2.088 ～ 17.213),PaO2/FiO2 ＜205 (OR =3.010,95％ CI 1.033 ～8.774) were independent risk factors for INSURE failure.Conclusion INSURE strategy failure was associated with gender,birth weight,gestation age,antenatal steroids utilization,PaO2,PaCO2 and PaO2/FiO2 of the first blood gas after birth.BW ＜ 1 000 g,PaCO2 ＞ 48 mmHg and PaO2/FiO2 ＜ 205 of the first blood gas after birth were independent risk factors for INSURE strategy failure.

Dynamic changes in adenosine monophosphate-activated protein kinase in neonatal rats with hypoxic ischemic encephalopathy / 中华围产医学杂志

Objective To determine the dynamic changes in adenosine monophosphate-activated protein kinase (AMPK) in neurons of neonatal rats suffering from hypoxic ischemic brain injury.Methods Twenty-four-hour old and seven-day old neonatal rats were used in this study.A classic primary cortical neuron oxygen glucose deprivation (OGD) model and neonatal rat hypoxic ischemic encephalopathy (HIE) model were employed.Lactic dehydrogenase (LDH) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were used to evaluate neuron viability and damage.The expression of phosphorylated adenosine monophosphate-activated protein kinase (P-AMPK),phosphorylated activated protein kinase (P-Akt) and Cleaved Caspase-3 in neurons and brain tissue was measured by Western blot at different time points after OGD or HIE.The Student-t test was used for statistical analysis.Results (1) Compared with the control group,LDH levels at 2,4,8 and 24 h after OGD were higher (all P＜0.05) and optical absorption levels of MTT were lower (all P＜0.05).(2) Levels of P-AMPK in the OGD group were higher than those in the control group,and showed a time-dependent increase at 30 min and 2,4,8 and 24 h (all P＜0.05).The expression levels of P-AMPK in the HIE group were higher than those in the control group (0.345 ± 0.038,0.387 ± 0.112 and 0.618 ± 0.075 at 1,3 and 7 days after HIE,and 0.132±0.032 in the control group,all P＜0.05).(3) The levels of P-Akt increased above the control levels at 30 min (0.991 ±0.134 vs 0.304±0.050),reached a maximum level at 2 h (1.183± 0.107),and then gradually declined,whereas the levels of Cleaved Caspase-3 started to increase at 30 min,and remained elevated at 24 h (all P＜0.05).Conclusion Following hypoxic ischemic brain damage,the expression of P-AMPK is significantly increased in both in vivo and in vitro studies in a time-dependent manner.

The evolvement of definition and nomenclature in bronchopulmonary dysplasia and advances in its treatment / 中国小儿急救医学

Bronchopulmonary dysplasia ( BPD) ,also called chronic lung disease ( CLD) ,is a com-mon respiratory disease of premature infants. It was first reported and named by Northway et al, carrying unique etiology,pathology and clinical features. BPD reported by Northway is referred as old or classic BPD. Manifestations and prognosis of premature infants with respiratory diseases have been improved significantly after evolutional changes by applying glucocorticoid and exogenous surfactant,as well as protective ventilator protocols after birth. Nowadays,incidents of severe BPD described by Northway are extremely low,whereas mild BPD,also called ‘new’ BPD,is much more common. Definition and nomenclature of BPD have been controversial since first being brought out in 1967. This article was focused on the definition and nomenclature and current advances in BPD treatment.

A retrospective analysis of 86 newborns with severe acute respiratory distress syndrome / 中华急诊医学杂志

Objective To investigate the diagnosis,treatment and prognosis of neonates with severe acute respiratory distress syndrome (ARDS) according to Berlin definition.Methods A retrospective study was carried to analyze the clinical features about diagnosis,treatment,chest X-ray findings,mortality,complications and ventilator parameters in 86 neonates with severe ARDS admitted in the NICU from January 2005 to December 2013.Results (1)Among the 86 cases,55 were cured,and 31 died with 36.0％ mortality.(2) Chest X-ray showed there was decreased lucency of bilateral lungs with ground-glass appearance,lung texture with thick chaos or dot flakes or patchy shadows in 36 neonates; diffuse infiltrates and extensive confluent consolidation shadows in bilateral lungs along with peripheral air brornchograms in 26 cases; heart shadow and diaphragmatic surface disappeared like a white lung change in 24 cases.(3) Persistent pulmonary hypertension of newborn as a complication occurred in 68 cases with 79.1％ incidence.(4) Eighty-six cases were categorized into survival group and death group.The results showed compared with the survival group,the neonates in death group required higher FiO2,and PaO2,and lower PaO2/FiO2 before mechanical ventilation (P ＜ 0.01),but needed higher initial PIP of mechanical ventilation (P ＜ 0.01).Conclusions Neonatal ARDS is still a kind of critical condition with high mortality and lack of evidence-based diagnostic criteria so far.The therapeutic strategy for neonatal ARDS should be a comprehensive measures in addition to appropriate respiratory support.

Efficacy comparison of aminophylline combined with naloxone and caffeine citrate in prevention of apnea of prematurity / 中华实用儿科临床杂志

Objective To investigate the efficacy and safety of aminophylline,caffeine citrate and aminophylline combined with naloxone in prevention of apnea of prematurity(AOP).Methods Ninety-four infants with a birth weight ＜ 1 500 g and gestational age ＜ 34 weeks admitted to Department of Pediatrics,Tongji Hospital Affiliated to Tongji Medical College,Huazhong University of Science and Technology between Jan.2010 and Jan.2012 were randomly divided into 3 groups.(1) Aminophylline group (n =30):30 infants received a loading dose of 4-5 mg/kg of aminophylline and then maintained by a dose of 2 mg/kg,with intravenous drip q12 h.(2) Caffeine citrate group(n =32):a loading dose of 20 mg/kg of caffeine citrate was followed by a daily maintained dose of 5 mg/kg,with intravenous drip per day.(3) Aminophylline combined naloxone group (observation group,n =32):32 infants were treated with Aminophylline combined with naloxone.After 6 hours of the first dose of aminophylline,a dose of 0.1 mg/kg naloxone was injected,q12 h.Then the two drugs were used alternately.The mortality and incidence of AOP,bronchopulmonary dysplasia(BPD),retinopathy of prematurity (ROP) and brain injury were evaluated,and drug-related side effects were recorded.Results 1.There was no significant difference in gender,gestational age,birth weight,maternal antenatal glucocorticoid application,pregnancy (including multiple pregnancy) and delivery,5 min Apgar score,oxygen therapy,and the application of positive airway pressure as well as pulmonary surfactant among the 3 groups(all P ＞0.05).2.Compared with aminophylline group,the incidence of apnea of caffeine group and observation group were significantly lower (F =6.704,P ＜ 0.05),but there was no significant difference between caffeine group and observation group (P ＞0.05).3.There was no statistically significant difference in mortality,duration of oxygen therapy,the incidence of ROP,brain injury and hearing loss,postmenstrual age,body weight at discharge,the duration and cost of hospitalization among the 3 groups(all P ＞0.05).4.The BPD incidence in caffeine group[9.4％ (3/32 cases)] and observation group [12.5％ (4/32 cases)] were lower than that in Aminophylline group [20.0％ (6/30 cases)],but there was no statistical significance among the 3 groups(P ＞ 0.05).5.No drug-related side effects were recorded in the 3 groups.Conclusions It is safe and effective to use aminophylline combined with naloxone in prevention of AOP,and its efficiency is similar to caffeine citrate.

Inhibitive effect of prolonged hyperoxic exposure on the protection of keratinocyte growth factor on alveolar epithelial type Ⅱ cells of rat fetus / 中华实用儿科临床杂志

Objective To explore the survival/proliferation,apoptotic and death effects of keratinocyte growth factor (KGF) in alveolar epithelial type Ⅱ cells (AT Ⅱ Cs) exposed to hyperoxia.Methods Primary culture of AT Ⅱ Cs from the Sprague-Dawley rat fetuses was studied under room air condition (210 mL/L O2) and hyperoxic condition (950 mL/L O2) for 0.5-12.0 h.Various concentrations of KGF (15 μg/L,25 μg/L,50 μg/L,75 μg/L,100 μg/L)were added into the cell cultures.Cells were randomly divided into room-air group,room-air-KGF group,hyperoxic-exposure group and hyperoxic-exposure-KGF group.The levels of intracellular reactive oxygen species (ROS),cleaved cysteinyl aspartate specific proteinase-3 (Caspase-3),cell death and proliferation of AT Ⅱ Cs were measured by flow cytometer,Western Blot,release of lactate dehydrogenase assays (LDH assays) and 3-(4,5-Dimethyhhiazol-2-yl)-2,5-diphenyhetrazolium bromide assays (MTT assays),respectively.Results Under room air condition,KGF could significantly increase AT Ⅱ Cs proliferation with 15-100 μg/L in a dose-dependent manner and significantly decrease LDH production at concentrations of 25-100 μg/L.Exposure to hyperoxia resulted in a significant increase in intracellular ROS production in AT Ⅱ Cs in a time-dependent manner compared with that of the room air group.Cell viability decreased and LDH release increased significantly in a time-dependent manner when AT Ⅱ Cs were exposed to 950 mL/L O2 for more than 4 h.After exposure to hyperoxia for 0.5 h and 1 h,KGF could significantly increase AT Ⅱ Cs proliferation in 15-75 μ g/L and significantly decrease LDH production at concentrations of 25-75 μg/L.After exposure to hyperoxia up to 4 h,higher viability was observed in 15 μg/L and 25 μg/L KGF group,and lower death rate presented in 25-100 μg/L KGF group.Further,prolnged hyperoxic exposure for 8 h,high viabilitv was shown only in 50 μg/L KGF group,and less death rate was observed only in 75 μg/L KGF group.In addition,no significant difference in viability and mortality was found between hyperoxic group and hyperoxic-KGF group after hyperoxic exposure for 12 h.Expression of cleaved Caspase-3 was significant higher after 4 h and 8 h hyperoxic exposure than that in room-air group ;at the same time,by adding 25 μg/L and 75.μg/L KGF led to decreased expression of Caspase-3 was detected,compared to hyperoxic group.Conclusions KGF may promote survival/proliferation,inhibited apoptosis and death of rat fetal AT Ⅱ Cs in room air condition or under temporary exposure to hyperoxia in vitro.However,prolonged exposure to hyperoxia may decrease the sensitivity of AEC Ⅱ Cs to KGF and limit its protective effects on lung injury.

Fetal inlfammatory response syndrome and neonatal diseases / 临床儿科杂志

The fetal inlfammatory response syndrome (FIRS) is a subclinical condition characterized by systemic acti-vation of the fetal innate immune system with a large number of pro-inlfammatory cytokines released. FIRS is the fetal coun-terpart of the systemic inlfammatory response syndrome (SIRS) described in adults. Intrauterine infection is the most common reason of FIRS. FIRS has been implicated as a cause of preterm labor, preterm white matter injury, bronchopulmonary dyspla-sia (BPD) and necrotizing enterocolitis (NEC).

Progress on prophylaxis and treatment of bronchopulmonary dysplasia / 中国小儿急救医学

Bronchopulmonary dysplasia (BPD) is a respiratory disorder that is frequently associated with premature infants.Prevention from its occurrence is perceived to be more valuable than its treatment due to the current lack of effective management.This article elaborated recent development in preventing premature birth and lung injuries caused by mechanical ventilation,oxygen toxicity,infection and inflammation,which played a central role in the development of BPD.

Construction of human surfactant protein B promoter luciferase reporter gene vectors and detection of their activities / 中国医师杂志

Objective To construct human surfactant protein B (SP-B) gene promoter luciferase reporter plasmids and detect their transcriptional activities in H441 cells.Methods (1)The fragment of SP-B promoter (-218/+ 435 bp) was acquired from human genome DNA by polymerase chain reaction (PCR) amplification and then was inserted into pGM-T vector by the T4 DNA ligase.The vector was transfected into TOP10 E.coli.The positive clone was identified by DNA sequencing.The identified target SP-B promoter sequence was cloned into pGL3-basic vector to construct the recombinant vector pGL3-basic-SP-B-promoter and was identified by enzyme digestion and sequencing; (2)The pGL3-basic-SP-B-promoter vector was converted into pGL4.17-SP-B-promoter vector through enzyme digestion.The identified recombinant vectors and control plasmid pRL-TK were transfected into H441 cells by lipofectamine 2000,and luciferase assays was performed using the dual-luciferase reporter assay system.Results The sequences of SP-B promoter in the recombinant luciferase reporter plasmids were consistent with the one published on Genebank.The firefly/renilla luciferase activity ratio of pGL3-basic/pGL4.17-SP-B-promoter vector (2.8 ± 1.1,66.5±3.8) was significantly higher than pGL3-Basic,pGL4.17 control vector (0.2 ±0.1,4.3 ±0.4) with statistical significance (t =4.182,27.419,P =0.000),respectively.The SP-B promoter activity of pGL4.17-SP-B-promoter vector was significantly higher than pGL3-basic-SP-B-promoter vector (t =27.712,P =0.000).Conclusions The pGL3-basic/pGL4.17-SP-B-promoter vectors are successfully constructed with SP-B promoter activity in H441 cells and pGL4.17-SP-B-promoter vector is the better choice for further study with higher luciferase activity.

Construction of eukaryotic cell expression vectors pIRES2-EGFP-SP-B-C/T 1580 and evaluation of their expressions in 293T cells / 中国医师杂志

Objective To construct two kinds of eukaryotic ccll expression vcctors pIRES2-EGFP-SP-B-C/T 1580 and evaluate their expressions in 293T cells,for the further study of relationship between polymorphism of surfactant protein B (SP-B) gene and bronchopulmonary dysplasia (BPD).Methods The eukaryotic pIRES2-EGFP-SP-B-C/T 1580 expression vectors were constructed by gene recombination,and identified by gene sequencing.The recombinant expression vectors were transfected into 293T cells by lipofectamine2000.The expression of green fluorescence protein in 293T cells was observed by fluorescence microscopy.The mRNAs and proteins of SP-B-C/T 1580 were tested and identified by reverse transcriptionpolymerase chain reaction-restriction fragment length polymorphism(RT-PCR-RFLP) and western blot.Results Two recombinant plasmids contained the complete cDNA of SP-B with the same sequence as in gene bank.The base of SP-B 1580 gene of pIRES2-EGFP-SP-B-C 1580 was C,that of pIRES2-EGFP-SP-B-T 1580 was T.After being transfected into 293T cells,highly efficient expression of SP-B-C/T 1580 gene was detected at mRNA and protein levels.Conclusions The pIRES2-EGFP-SP-B-C/T 1580 eukaryotic cell expression vectors were successfully constructed.

Gene polymorphism in intron 4 of surfactant protein-B in bronchopulmonary dysplasia infants / 中华围产医学杂志

ObjectiveTo investigate the change of gene polymorphorism of surfactant protein-B (SP-B) intron 4 in infants with bronchopulmonary dysplasia (BPD).MethodsForty-five infants with BPD (BPD group) and ninety-nine infants without lung diseases (control group) who admitted into Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology from July 2008 to July 2011 were selected into this study.Genotyping for fragment length polymorphism of SP-B intron 4 was performed by polymerase chain reaction (PCR),agarose gel electrophoresis,cloning and sequencing methods in both groups.Differences of allele frequencies (invariant allele and variant allele) and genotype frequencies (invariant genotype and variant genotype) between BPD group and control group were analyzed.The differences of gestational age and birth weight between the two groups were compared with Independent-Samples t test.The gender composition and differences of allele or genotype frequencies between the two groups were compared with Chi-square test.Results Invariant allele frequencies in BPD group and control group were 83.3％ (75/90) and 92.0％ (182/198),and variant allele frequencies were 16.7％ (15/90,including eight insertion alleles and seven deletion alleles) and 8.1％ (16/198,including eight insertion alleles and eight deletion alleles).There were significant differences between the two groups (x2 =4.75,P =0.029).In BPD group,there were 32 cases (71.1 ％,32/45) invariant genotypes and 13 cases (28.9 ％,13/45,including seven cases insertions and six cases deletions) variant genotypes; in the control group,there were 85 cases invariant genotypes (85.8％,85/99) and 14 cases (14.1％,14/99,six insertions and eight deletions) variant genotypes.Significant difference was found between the two groups (x2=4.42,P＜0.036). ConclusionsVariations of SP-B intron 4 were more in BPD infants,and the variation of SP-B intron 4 might be associated with BPD.

Effects of hyperoxia on cytoplasmic thioredoxin system in alveolar type epithelial cells of premature rats / 华中科技大学学报（医学）（英德文版）

This study investigated the effects of hyperoxia on dynamic changes of thioredoxin-1 (Trx1) and thioredoxin reductase-1 (TrxR1) in alveolar type II epithelial cells (AECII) of premature rats. Pregnant Sprague-Dawley rats were sacrificed on day 19 of gestation. AECII were isolated and purified from the lungs of premature rats. When cultured to 80% confluence, in vitro cells were randomly divided into air group and hyperoxia group. Cells in the hyperoxia group were continuously exposed to 95% O(2)/5% CO(2) and those in the air group to 95% air/5% CO(2). After 12, 24 and 48 h, cells in the two groups were harvested to detect their reactive oxygen species (ROS), apoptosis, TrxR1 activity and the expressions of Trx1 and TrxR1 by corresponding protocols, respectively. The results showed that AEC II exposed to hyperoxia generated excessive ROS and the apoptosis percentage in the hyperoxia group was increased significantly at each time points as compared with that in the air group (P0.05). Western blotting showed the changes of Trx1 protein expressions in the hyperoxia group paralleled those of Trx1 mRNA expressions revealed by RT-PCR. It was concluded that hyperoxia can up-regulate the protective Trx1/TrxR1 expressed by AECII in a certain period, however, also cause dysfunction of the cytoplasmic thioredoxin system by decreasing TrxR1 activity, which may contribute to the progression of oxidative stress and cell apoptosis and finally result in lung injury.

Retinoic aacid diminished the expression of MMP-2 in hyperoxia-exposed premature rat lung fibroblasts through regulating mitogen-activated protein kinases / 华中科技大学学报（医学）（英德文版）

This study examined the effects of retinoic acid (RA), PD98059, SP600125 and SB203580 on the hyperoxia-induced expression and regulation of matrix metalloproteinase-2 (MMP-2) and metalloproteinase-2 (TIMP-2) in premature rat lung fibroblasts (LFs). LFs were exposed to hyperoxia or room air for 12 h in the presence of RA and the kinase inhibitors PD98059 (ERK1/2), SP600125 (JNK1/2) and SB203580 (p38) respectively. The expression levels of MMP-2 and TIMP-2 mRNA were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). MMP-2 activity was measured by zymography. The amount of p-ERK1/2, REK1/2, p-JNK1/2, JNK1/2, p-p38 and p38 was determined by Western blotting. The results showed that: (1) PD98059, SP600125 and SB203580 significantly inhibited p-ERK1/2, p-JNK1/2 and p-p38 respectively in LFs; (2) The expression of MMP-2 mRNA in LFs exposed to hyperoxia was decreased after treatment with RA, SP600125 and SB203580 respectively (P0.05). Meanwhile, RA, PD98059, SP600125 and SB203580 had no effect on the expression of TIMP-2 mRNA in LFs exposed to room air or hyperoxia (P>0.05); (3) The expression of pro- and active MMP-2 experienced no change after treatment with RA or SP600125 in LFs exposed to room air (P>0.05), but decreased remarkably after hyperoxia (P<0.01 or 0.05). SB203580 inhibited the expression of pro- and active MMP-2 either in room air or under hyperoxia (P<0.01). PD98059 exerted no effect on the expression of pro- and active MMP-2 (P<0.05). It was suggested that RA had a protective effect on hyperoxia-induced lung injury by down-regulating the expression of MMP-2 through decreasing the JNK and p38 activation in hyperoxia.

Suppressed expression of thioredoxin-2 by small interference RNA in A549 cells exposed to hyperoxia reduced expression of nicotinamide-adenine dinucleotide dehydrogenase subunit 1 and cytochrome C oxidase Ⅰ / 中华围产医学杂志

Objective To explore the effects of expression of thioredoxin-2(Trx-2) suppressed by small interference RNA(SiRNA) in A549 cells exposed to hyperoxia on expression of nicotinamide adenine dinucleotide(NADH) dehydrogenase subunit 1(ND1)and cytochrome C oxidase Ⅰ(COX Ⅰ). Methods A549 cells were gained by serial subcultivation in vitro and transfered with synthetic Trx-2 sequence-specific SiRNA and then were randomly divided into air group without interference,hyperoxia group without interference,air group after interference,and hyperoxia group after interference.After exposure to oxygen or room air for 12,24 and 48 h,expressions of Trx-2,ND1 and COX Ⅰ mRNA of these cells were detected by reverse transcription-polymerase chain reaction (RT-PCR),and Trx-2 protein was detected by Western blot. Results (1)Sequence-specific SiRNAtargeting Trx-2 could significantly down-regulate its expression in A549 cells.(2)Trx-2 mRNA levds inhyperoxia group without interference at 24 h was higher than those in air group without interference(0.7799±0.1249 VS 0.4424±Ⅰ.1140,P<0.05).Th-2 mRNA levels in hyperoxia group after ireedcrence at 24 hand 48 h were 0.2774±0.0174 and 0.2587±0.0069,lower than those in air group after interference andhyperoxia group without interference (P<0.05).(3)ND1 mRNA levels in hyperoxia group without interference at 24 h was 0.6609±0.0368,lower than those in air group without interference(0.8898±0.1049)(P<0.05).ND1 mRNA levels in hyperoxia group after interference at 12 h was 0.8848±0.0135,higher than those in air group after imederence(P<0.05).ND1 mRNA levels in hypemxia group afterinterference at 48 h was 0.3808±0.0937,lower than those in air group after imerference and hyperoxiagroup without interference(P<0.05).(4)COXI mRNA levels in hypemxia group without inteference at 12,24 and 48 h were 1.7313±0.4331,2.1929±0.6722 and 2.0754±0.2584,higher than those in air group witheUt interference,respectively (P<0.05). Conclusions ND1 and COXⅠ participate in thedevelopment of hyperoxia indUCed lung.injury,and Trx-2 is likely to have protective effect on mitochondria ofA549 cells in hyperoxia lung injury.

Expression of apoptosis signal-regulating kinase 1 in pulmonary tissue of premature newborn rat exposed to hyperoxia / 中华围产医学杂志

Objective To investigate the changes and potential roles of the expression of apoptosis signal-regulating kinase 1(ASK1),thioredoxin(Trx)and thioredoxin reductase(TrxR)in the pathogenesis of lung injury of premature newborn rats exposed to hyperoxia. Methods In the first day after delivery,preterm SD rats were randomly divided into air group and hyperoxia group with 64 rats in each.The rats were respectively sacrificed at 1,4,7,10 and 14 days after air or hyperoxia exposure.Sections of 1ungs were stained with HE to observe the histologic changes.Trx and TrxR mRNA were detected by reverse transcription-polymerase chain reaction(RT-PCR).Immunohistochemistry was used to detect the expression and distribution of ASK1.Western blot was used to detect the expression of ASK1 protein. Results Rats in hyperoxia group showed typical lung injury,which was characterized by alveolitis and delayed of lung development.Immunohistochemistry detected that ASK1 expressed generally in the cytoplasm of both alveolar epithelial cells and vascular endothelial cells:ASK1 protein expression in hyperoxia group at 1th and 4th day were 0.4382±0.0227 and 0.5270±0.0432,higher than in the air group(0.3458±0.0263 and 0.3760±0.0058)(P<0.01),and it was until 7th day that the expression became weaker(0.4343±0.0254),but still higher compared with the air group(0.3473±0.0220)(P<0.01).Compared with the air group,Trx and TrxR mRNA of the hyperoxia group increased significantly and peaked at lOth day(0.6860±0.0811)and 7th day(2.0351±0.1600),respectively(P<0.05).ASK1 protein expressions resulting

Effect of ultraviolet irradiation dose and style on 25-hydroxyvitamin D and bone metabolism in growing rats / 中国组织工程研究

BACKGROUND:Sunshine time in northem region is short in winter,the infants and young children are vulnerable to lack of vitamin D. Up-to-date textbooks and the guidelines formulated by Chinese Medical Association account that glass block ultraviolet and indoor exposure to human is meaningless. Early studies have shown that sunlight exposure through glass had meaning in rats,but it was difficult to accurately quantify,while outdoor exposure in rats is difficult to continue. This expedment uses B-band ultraviolet rays,which has the impact on vitamin D metabolism in some wavelengths,to facilitate further study.OBJECTIVE:To study the effect of ultraviolet B exposure in laboratory on 25-hydroxy vitamin D(25-OHD)level and bone metabolism in the serum of growing rats.DESIGN,TIME AND SETTING:A randomized controlled animal experiment was performed in June 2007 in the ExperimantalAnimal Center of Chinese PLA General Hospital.MATERIALS:Forty male 21-day-old Wistar rats were employed in this study. Ultraviolet waves were sourced from an artificial UV light instrument(wavelength 280-350 μm,irradiation intensity 5.5μW/cm~2).METHODS:Forty Wistar rats were divided into four groups by random sampling table,exposed to different doses of ultraviolet Bwave. Direct exposure group:direct exposure for 20 minutes at an irradiation dose of 4.2 mJ/(cm~2·d);Indirect exposure 60 and 120 min groups:exposure through a single pane of glass for 60 and 120 minutes at an irradiation dose of 0.36 and 0.72 mJ/(cm~2·d).Control group:no exposure was given. For the direct exposure group,the lamp was placed above the cage. A 3-mm-thick pane of glass(common window glass) was placed underneath the lamp in the indirect exposure groups. Exposure groups were given irradiation for successive 20 days.MAIN OUTCOME MEASURES:Serum 25-OHD,bone alkaline phosphatase (BALP),and bone mineral density (BMD) were measured on day 21.RESULTS:25-OHD was significantly higher in all exposure groups compared with the control group (P＜0.001),but there was no difference between the direct exposure group and two indirect exposure groups. BALP was significantly lower in the exposure groups than control group (P＜0.001),it was also significantly lower in the 120-min indirect group than in the 60-min indirect group (P=0.022). There was a positive correlation between exposure dose and 25-OHD (r=0.555,P=0.002) and a negative correlation between exposure dose and BALP (r=0.595,P=0.001),also a negative correlation between 25-OHD and BALP (r=0.569,P=0.002),but there were no differences between groups for BMD. Exposure dose exhibited a threshold,serum 25-OHD and BALP no longer increased or decreased when it was 0.36 mJ/(cm~2·d).CONCLUSION:Midwave ultraviolet rays might affect serum 25-OHD and BALP levels in the growing rats through glass exposure,with no significant difference compared to direct exposure. The B-band ultraviolet exposure dose may play an important role in serum 25-OHD synthesis,but there is a threshold dose for the synthesis. Low-dose and prolonged exposure time also achieve threshold exposure.

Effect of hyperoxia on Notch receptor in alveolar epithelial type Ⅱ cells of preterm rats / 中华急诊医学杂志

Objective To observe the effects of hyperoxia on Notch 1 receptor of alveolar epithelial type Ⅱ cells (AEC Ⅱ), in a hetcrocellular culture of alveolar epithelial type Ⅱ cells and lung flbroblasts(LF), in order to explore Notch signaling in hyperoxic induced lung injury and thus make theoretical basis for prevention and treatment of a acute/chronie neonatal lung injury. Method Twelve Spragne Dawkey female rats with 200～220 g and 3 Spragne Dawkey male rats with 220～250 g were offered from experimental animal centre of Tongji Medical Colleege, Huazhong University of Science and Technology. The AEC Ⅱ/ LF co-culture system was established successfully. AEC H s from premature rats were randomly assigned to 2 groups: air control group and hyperoxia group. Air control group was kept in room air 50% ml/L CO2 enviromnent at 37°C, while hyperoxia group was exposed to 950 ml/L O2 + 250 ml/L CO2. Immuno-histochemistry was taken to detect Notch 1. Fluorescent quantitafive PCR was used to quantify the Notch 1 mRNA. MTT method was taken to assess cen proliferation viability.Flow eytometry double label method was used to detect cell percentages. Results In hyperoxia group:Notch 1 activation was inhibited, and Notch 1 mRNA decreased to 0.43,0.29,0.11,0.03 fold of control (95% confidence limit). AEC Ⅱ percentage descended predominantly[ 24 h hyperoxia group vs. control group: (68.92±6.88)%vs. (90.35±4.01)%, P =0.006;48 h hyperoxia group vs. control group: (38.03±3.27) vs. (61.47±4.81)%, P =0.000;72 h hyperoxia group vs. control group:(20.13±4.45)% vs. (52.05±3.35)%, P =0.000;96 h hyperoxia group vs. control group:(8.17±1.99)% vs. (52.59±2.93)%, P =0.0001 while that d AECI rised[24 h hyperoxia group vs. contrd group:(0.11±0.03)% vs. (0.01±0.01)%, P=0.006;48h hyperoxia group vs. control gnmp:(49.73±3.45)% vs. (16.13±2.13)%, P =0.000;72 h hyperoxia group vs. control group: (52.43±3.14) % vs. (5.98±0.95) %, P = 0.000;96h hyperorxia group vs. control group:(19.85±3.26)% vs. (29.03±3.16)%, P =0.007]. Comclusions Hyperoxia may inhibit Notch signaling pathway, which can weaken proliferation and disdifferentiation of AEC Ⅱ s. Investigations on how to control Notch signaling will provide fresh thoughts for alveolar epithelium repairing.

Effects of hyperoxia on the dynamic expression of Aquaporin5 in premature rats lung development / 华中科技大学学报（医学）（英德文版）

To explore the dynamic expression and role of Aquaporin5 (AQP5) in lung development and hyperoxia lung injury, gestation 21-day Sprague-Dawley (SD) rats (term=22 days) were randomly assigned to air group and hyperoxia group within 12-24 h after birth. The rats in hyperoxia group were continuously exposed to about 85% oxygen and those in air group to room air. After 1 to 14 days of exposure, total lung RNA was extracted and the expression of AQP5 mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Immunohistochemistry and western-blot were used to detect the expression of AQP5 protein. The results showed that the expression of AQP5 in premature rats lung could be detected at various time points after birth, and the positive staining was restricted to the type I alveolar epithelial cells. In air group, the AQP5 expression was detected in a very low level at day 1, but exhibited a persistent increase after birth. Compared with the air group, the expression of AQP5 in hyperoxia group was increased at day 1, and had significant difference in mRNA level (P<0.05), but decreased significantly in mRNA and protein levels after 4 to 14 days (P<0.01 or P<0.05 respectively). It was concluded that AQP5 might play a key role in the alveolar period of premature rats by regulating the lung water balance. Hyperoxia exposure leads to a down-regulation of the AQP5 expression, which may be an important factor for the development of hyperoxia lung injury.

Effects of Hyperoxia on the Dynamic Expression of Aquaporin5 in Premature Rats Lung Development / 华中科技大学学报（医学）（英德文版）

To explore the dynamic expression and role of Aquaporin5 (AQP5) in lung development and hyperoxia lung injury, gestation 21-day Sprague-Dawley (SD) rats (term=22 days) were randomly assigned to air group and hyperoxia group within 12-24 h after birth. The rats in hypreoxia group were continuously exposed to about 85% oxygen and those in air group to room air. After 1 to 14 days of exposure, total lung RNA was extracted and the expression of AQP5 mRNA was detected by reverse transcription polymerase chain reaction (RT-PCR). Immunohistochemistry and western-blot were used to detect the expression of AQP5 protein. The results showed that the expression of AQP5 in premature rats lung could be detected at various time points after birth, and the positive staining was restricted to the type Ⅰ alveolar epithelial cells. In air group, the AQP5 expression was detected in a very low level at day 1, but exhibited a persistent increase after birth. Compared with the air group, the expression of AQP5 in hyperoxia group was increased at day l, and had significant difference in mRNA level (P＜0.05), but decreased significantly in mRNA and protein levels after 4 to 14 days (P＜0.01 or P＜0.05 respectively). It was concluded that AQP5 might play a key role in the alveolar period of premature rats by regulating the lung water balance. Hyperoxia exposure leads to a down-regulation of the AQP5 expression, which may be an important factor for the development of hyperoxia lung injury.

Incidence rate and high-risk factors of peri-intraventricular hemorrhage in 1 122 preterm infants / 中国组织工程研究

BACKGROUND: Peri-intraventricular hemorrhage (PIVH) in preterm infants is one of the most important reasons for mortality and disability. Moreover, investigative exponents may bring supported data for incidence rate of PIVH and high-risk factors of preterm infants with PIVH.OBJECTIVE: To explore the incidence rate and analyze the high-risk factors of PIVH in preterm infants.DESIGN: Survey and analysis.SETTING: Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology; Beijing Obstetrics & Gynecology Hospital, Capital Medical Universit; Qinhuangdao Maternity and Infants' Hospital of Hebei Province.PARTICIPANTS: A total of 1 122 preterm infants of 26.3-36.8 gestational age were selected from Beijing Obstetrics & Gynecology Hospital, Qinhuangdao Maternity and Infants' Hospital from January 2002 to August 2005. All infants received ultrasonic examination on skull within 1 week. There were 594 boys and 528 girls, and the birth weight was 850-4 500 g.METHODS: All infants received ultrasonic examination on skull within 1 week. New Philips 5500 and GE Healthcare Logiq 400 ultrasonic diagnosis devices were provided by Philip Company, Dutch and GE Company, respectively.MAIN OUTCOME MEASURES: The incidence rate and related high-risk factors of PIVH.RESULTS: All 1 122 preterm infants were involved in the final analysis. Among 1 122 preterm infants, 619 cases (55.2%) had PIVH; especially, 110 had severe PIVH with the degree more than Ⅲ, which was accounted for 17.8%.High-risk factors were mainly low gestational age, low birth weight, mechanical ventilation, hypoglycemia, hypercapnia,hyperlactic acidemia, acidosis, hypoxia, abnormal blood coagulation, and so on. Antenatal corticosteroid could reduce the incidence rate of PIVH. However, there was no obvious effect on preterm infants of old gestational age.CONCLUSION: Routine intracranial ultrasonic examination is useful for the diagnosis of PIVH in preterm infants.