A method for determinattion of monoamine neurotransmitters and related compounds in microdialysis solution by high performance liquid chromatography (HPLC) with pulsed amperometric detection was described. A comparison of response of iso potential anperometric (AD) and pulsed amperometric detection (PAD) was made. The results indicated that the sensitivity of PAD was 1.2 fold that of AD. The quantitative determination of monoamine neurotransmitters and related compounds was carried out with 3,4-dihydroxybenzylamine (DHBA) as internal standerd. The recoveries of monoamine neurotransmitters in microdialysis solution are 71% ～ 101%.

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.

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

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.

Objective To investigate the role of opioid receptors in the protective effects of isoflurane-induced delayed preconditioning against myocardial ischemia-reperfusion (I/R) injury in rabbits. Methods Forty male New Zealand white rabbits weighing 2.0-2.5 kg were randomly assigned into 4 groups ( n = 10 each) : group I sham operation (S); group II I/R; group Ⅲ isoflurane + I/R (Iso) and group IV Iso + naloxone + I/R (Nal). Myocardial I/R was induced by 40 min occlusion of left anterior descending branch (LAD) of coronary artery followed by 120 min reperfusion. In group Ⅲ (Iso) 2% isoflurane in 100% O2 was inhaled for 2 h and I/R was produced 24 h later. In group IV (Nal) naloxone 6 mg/kg was given iv 10 min before 2 h of 2% isoflurane inhalation and I/R was produced 24 h later. At the end of 120 min reperfusion, infarct size (IS) and area at risk (AAR) were determined by Evan's blue and TTC staining. Myocardial ultrastructure was examined by electron microscopy. The phosphorylated p38MAPK protein expression in myocardium was determined by Western blot. Results The IS was significantly smaller in group Iso ( Ⅲ ) ( 19.7% ± 2.8%) than in I/R group ( II ) (37.8% ±1.7%) (P<0.05). The phosphorylated p38MAPK protein expression in myocardium was significantly lower in group Iso than in group I/R. Microscopic examination showed less myocardial damage in Iso group than in group I/R. The protective effects of delayed preconditioning by isoflurane was prevented by naloxone pretreatment. ConclusionOpioid receptors may be involved in the protective effects of delayed preconditioning by isoflurane against myocardial I/R injury.

Objective To investigate the effects of isoflurane delayed preconditioning(IDP) on myocardial proteomin rabbits with myocardial ischemia-reperfuaion(I/R).mjury.Methods Eight New Zealand white rabbits of both sexes weighing 2.0-2.5 kg were randomly divided into 2 groups(n=4 each):I/R group and IDP group.Myocardial I/R Wgg induced by occlusion of left anterior descending artery for 40 min followed by 120 min repednsion.In group IDP.the animals inhaled 2%isoflurane for 2 h,undergoing I/R 24 h later.At the end of 120 min reperfusion,the myocardium of left ventricle anterior wall was removed for two-dimensional gel electrophorvsis.The different protein spots were analyzed by means of mass chromatography.Results There were 13 different protein spots between group I/R and IDP.Of the 13 proteins,the expression of 10 spots Was up-regulated and 3 spots down-regulated in quantity.Eleven protein spots of all spots were identified by means of MALDI-TOF-MS.Conclusion IDP can aNenuate myocardial I/R injury in rabbits and it may be related to the alteration in proteome of myocardium.

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.

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.

This paper describes the analysis of insitu polymerization of monomeric reactants (PMR) polyimide resin solution by reversed phase ion pair suppression chromatography. the mobile phase consists of acetonitrile and water. The methyl sulphonic acid was used as an ion-pair reagent in the mobile phase. The addition of sodium perchlorate was required to increase the ionic strength of the mobile phase. The information was obtained on monomeric isomer distribution of PMR polyimide resin solution and purity of prepared materials.

The influence of platelet-derived growth factor (PDGF) on lung development in newborn rats and the effect of retinoic acid (RA) on PDGF in lung development were investigated. Newborn Sprague-Dawley (SD) rats were randomly assigned to two groups: control group and RA group. The rats in RA group was intraperitoneally injected with all trans-retinoic acid (500 microg/kg every day) for consecutive 3 days after birth, while those in the control group were not subjected to intervention. Immunohistochemical assay was performed to locate the expression of PDGF. mRNA levels of PDGF were measured by reverse transcription polymerase chain reaction (RT-PCR) at age of 1, 3, 5, 7, 10, 14, 21 days. The method of radial alveolar counts (RAC) was used to measure the amount of the alveoli of the lungs. It was found that with increasing days, levels of PDGF-A and PDGF-B changed to verying degrees. RA could elevate significantly the expression levels of PDGF-A mRNA and protein (P<0.01), but not affect the expression levels of PDGF-B mRNA and protein markedly (P>0.05). It is suggested that PDGF might play an important role in lung development. RA can stimulate lung development through increasing the expression levels of PDGF-A mRNA and protein.
Animals ; Animals, Newborn ; Lung ; growth & development ; metabolism ; Platelet-Derived Growth Factor ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tretinoin ; pharmacology