Effect of SMOF lipid emulsion on physical growth and extrauterine growth retardation in very preterm infants: Insights from a multicenter retrospective cohort study.

OBJECTIVE: The aim of this study was to investigate the effects of soybean, medium-chain triacylglycerols (MCTs), olive oil, and fish oil (SMOF) on short-term clinical outcomes, physical growth, and extrauterine growth retardation (EUGR) in very preterm infants. METHODS: This was a multicenter retrospective cohort study of very preterm infants hospitalized in neonatal intensive care units at five tertiary hospitals in China between January 2021 and December 2021. According to the type of fat emulsion used in parenteral nutrition (PN), eligible very preterm infants were divided into the MCTs/long-chain triacylglycerol (MCT/LCT) group and SMOF group. Change in weight z-score (weight Δz) between measurements at birth and at 36 wk of postmenstrual age or at discharge, the incidence of EUGR, and short-term clinical outcomes between the two groups were compared and analyzed. RESULTS: We enrolled 409 very preterm infants, including 205 in the MCT/LCT group and 204 in the SMOF group. Univariate analysis showed that infants in the SMOF group had significantly longer duration of invasive mechanical ventilation and PN, longer days to reach total enteral nutrition, and a higher proportion of maximum weight loss than those in MCT/LCT group (all P < 0.05). After adjusting for the confounding variables, multifactorial logistic regression analysis of short-term clinical outcomes showed that SMOF had protective effects on PN-associated cholestasis (odds ratio [OR], 0.470; 95% confidence interval [CI], 0.266-0.831) and metabolic bone disease of prematurity (OR, 0.263; 95% CI, 0.078-0.880). Additionally, SMOF was an independent risk factor for lower weight growth velocity (ß = -0.733; 95% CI, -1.452 to -0.015) but had no effect on the incidence of EUGR (OR, 1.567; 95% CI, 0.912 to -2.693). CONCLUSION: Compared with MCT/LCT, SMOF can reduce the risk for PN-associated cholestasis and metabolic bone disease of prematurity in very preterm infants and has a negative effect on growth velocity but has no effect on the incidence of EUGR.

[Comparison of the impact of different fat emulsions on clinical outcomes in preterm infants with varying duration of parenteral nutrition: a randomized controlled multicenter study]. / ä¸¤ç§è„‚è‚ªä¹³å‰‚ä¸åŒè‚ å¤–è¥å »æ—¶é—´å¯¹æ—©äº§å„¿ä¸´åºŠç»“å±€å½±å“çš„æ¯”è¾ƒï¼šä¸€é¡¹éšæœºå¯¹ç §å¤šä¸­å¿ƒç ”ç©¶.

OBJECTIVES: To compare the impact of two types of fat emulsion on clinical outcomes in preterm infants with varying duration of parenteral nutrition (PN). METHODS: Preterm infants meeting the inclusion criteria were randomly assigned to two groups: medium/long-chain triglyceride fat emulsion (referred to as MCT/LCT) group or multi-oil fat emulsion (containing soybean oil, medium-chain triglycerides, olive oil, and fish oil; referred to as SMOF) group. The infants were stratified into groups based on the duration of PN (15-21 days, 22-28 days, and ≥29 days). Clinical characteristics, nutritional status, biochemical indicators, and clinical outcomes were compared between the two groups. RESULTS: Compared with the MCT/LCT group, the SMOF group had lower peak levels of triglyceride during the hospital stay in preterm infants with PN of 15-21 days, 22-28 days, and ≥29 days, respectively (P<0.05). Logistic regression trend analysis showed that with a longer duration of PN, the risk of parenteral nutrition-associated cholestasis (PNAC) and bronchopulmonary dysplasia (BPD) significantly increased in the MCT/LCT group (P<0.05), while the risk of brain injury did not significantly change (P>0.05). In the SMOF group, the risks of PNAC and BPD did not significantly change with a longer duration of PN (P>0.05), but the risk of brain injury significantly decreased (P=0.006). CONCLUSIONS: Compared to MCT/LCT, SMOF have better lipid tolerance. With a longer duration of PN, SMOF does not increase the risks of PNAC and BPD and had a protective effect against brain injury. This suggests that in preterm infants requiring long-term PN, the use of SMOF is superior to MCT/LCT.

Analysis of risk factors for parenteral nutrition-associated cholestasis in preterm infants: a multicenter observational study.

BACKGROUND: It is proposed that the development of parenteral nutrition-associated cholestasis (PNAC) was significantly associated with preterm birth, low birth weight, infection, etc.; however, the etiology and pathogenesis of PNAC are not fully understood. Most of the studies examining PNAC-associated risk factors were single-center studies with relatively small sample sizes. OBJECTIVE: To analyze the risk factors associated with PNAC in preterm infants in China. METHODS: This is a retrospective multicenter observational study. Clinical data on the effect of multiple oil-fat emulsions (soybean oil-medium chain triglycerides-olive oil-fish oil, SMOF) in preterm infants were collected from a prospective multicenter randomized controlled study. A secondary analysis was performed in which preterm infants were divided into the PNAC group and the non-PNAC group based on the PNAC status. RESULTS: A total of 465 cases very preterm infants or very low birth weight infants were included in the study in which 81 cases were assigned to the PNAC group and 384 cases were assigned to the non-PNAC group. The PNAC group had a lower mean gestational age, lower mean birth weight, longer duration of invasive and non-invasive mechanical ventilation, a longer duration oxygen support, and longer hospital stay (P < 0.001 for all). The PNAC group had higher respiratory distress syndrome, hemodynamically significant patent ductus arteriosus, necrotizing enterocolitis (NEC) with stage II or higher, surgically treated NEC, late-onset sepsis, metabolic bone disease, and extrauterine growth retardation (EUGR) compared to the non-PNAC group (P < 0.05 for all). In contrast with the non-PNAC group, the PNAC group received a higher maximum dose of amino acids and fat emulsion, more medium/long-chain fatty emulsion, less SMOF, had a longer duration of parenteral nutrition, lower rates of breastfeeding, higher incidence of feeding intolerance (FI), more accumulated days to achieve total enteral nutrition, less accumulated days of total calories up to standard 110 kcal/kg/day and slower velocity of weight growth (P < 0.05 for all). Logistic regression analysis indicated that the maximum dose of amino acids (OR, 5.352; 95% CI, 2.355 to 12.161), EUGR (OR, 2.396; 95% CI, 1.255 to 4.572), FI (OR, 2.581; 95% CI, 1.395 to 4.775), surgically treated NEC (OR, 11.300; 95% CI, 2.127 ~ 60.035), and longer total hospital stay (OR, 1.030; 95% CI, 1.014 to 1.046) were independent risk factors for the development of PNAC. SMOF (OR, 0.358; 95% CI, 0.193 to 0.663) and breastfeeding (OR, 0.297; 95% CI, 0.157 to 0.559) were protective factors for PNAC. CONCLUSIONS: PNAC can be reduced by optimizing the management of enteral and parenteral nutrition and reducing gastrointestinal comorbidities in preterm infants.

Effects of mixed oil emulsion on short-term clinical outcomes in premature infants: A prospective, multicenter, randomized controlled trial.

OBJECTIVE: This study compared the clinical effects of two different lipid emulsions in premature infants with gestational age < 32 weeks (VPI) or birth weight < 1500 g (VLBWI) to provide an evidence-based medicine basis for optimizing intravenous lipid emulsion. METHODS: This was a prospective multicenter randomized controlled study. A total of 465 VPIs or VLBWIs, admitted to the neonatal intensive care unit of five tertiary hospitals in China from March 1, 2021 to December 31, 2021, were recruited. All subjects were randomly allocated into two groups, namely, medium-chain triglycerides/long-chain triglycerides (MCT/LCT) group (n = 231) and soybean oil, medium-chain triglycerides, olive oil, and fish oil (SMOF) group (n = 234). Clinical features, biochemical indexes, nutrition support therapy, and complications were analyzed and compared between the two groups. RESULTS: No significant differences were found in perinatal data, hospitalization, parenteral and enteral nutrition support between the two groups (P > 0.05). Compared with the MCT/LCT group, the incidence of neonates with a peak value of total bilirubin (TB) > 5 mg/dL (84/231 [36.4% vs. 60/234 [25.6%]), a peak value of direct bilirubin (DB) ≥ 2 mg/dL (26/231 [11.3% vs. 14/234 [6.0%]), a peak value of alkaline phosphatase (ALP) > 900 IU/L (17/231 [7.4% vs. 7/234 [3.0%]), and a peak value of triglycerides (TG) > 3.4 mmol/L (13/231 [5.6% vs. 4/234[1.7%]]) were lower in the SMOF group (P < 0.05). Univariate analysis showed that in the subgroup analysis of < 28 weeks, the incidence of parenteral nutrition-associated cholestasis (PNAC) and metabolic bone disease of prematurity (MBDP) were lower in the SMOF group (P = 0.043 and 0.029, respectively), whereas no significant differences were present in the incidence of PNAC and MBDP between the two groups at > 28 weeks group (P = 0.177 and 0.991, respectively). Multivariate logistic regression analysis revealed that the incidence of PNAC (aRR: 0.38, 95% confidence interval [CI]: 0.20-0.70, P = 0.002) and MBDP (aRR: 0.12, 95% CI: 0.19-0.81, P = 0.029) in the SMOF group were lower than that in the MCT/LCT group. In addition, no significant differences were recorded in the incidence of patent ductus arteriosus, feeding intolerance, necrotizing enterocolitis (Bell's stage ≥ 2), late-onset sepsis, bronchopulmonary dysplasia, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity and extrauterine growth retardation between the two groups (P > 0.05). CONCLUSIONS: The application of mixed oil emulsion in VPI or VLBWI can reduce the risk of plasma TB > 5 mg/dL, DB ≥ 2 mg/dL, ALP > 900 IU/L, and TG > 3.4 mmol/L during hospitalization. SMOF has better lipid tolerance, reduces the incidence of PNAC and MBDP, and exerts more benefits in preterm infants with gestational age < 28 weeks.

Predicting risk of severe neonatal outcomes in preterm infants born from mother with prelabor rupture of membranes.

BACKGROUND: Perinatal complications are common burdens for neonates born from mother with pPROM. Physicians and parents sometimes need to make critical decisions about neonatal care with short- and long-term implications on infant's health and families and it is important to predict severe neonatal outcomes with high accuracy. METHODS: The study was based on our prospective study on 1001 preterm infants born from mother with pPROM from August 1, 2017, to March 31, 2018 in three hospitals in China. Multivariable logistic regression analysis was applied to build a predicting model incorporating obstetric and neonatal characteristics available within the first day of NICU admission. We used enhanced bootstrap resampling for internal validation. RESULTS: One thousand one-hundred pregnancies with PROM at preterm with a single fetus were included in our study. SNO was diagnosed in 180 (17.98%) neonates. On multivariate analysis of the primary cohort, independent factors for SNO were respiratory support on the first day,, surfactant on day 1, and birth weight, which were selected into the nomogram. The model displayed good discrimination with a C-index of 0.838 (95%CI, 0.802-0.874) and good calibration performance. High C-index value of 0.835 could still be reached in the internal validation and the calibration curve showed good agreement. Decision curve analysis showed if the threshold is > 15%, using our model would achieve higher net benefit than model with birthweight as the only one predictor. CONCLUSION: Variables available on the first day in NICU including respiratory support on the first day, the use of surfactant on the first day and birthweight could be used to predict the risk of SNO in infants born from mother with pPROM with good discrimination and calibration performance.

Latency period of PROM at term and the risk of neonatal infectious diseases.

To find the risk of time thresholds of PROM for infectious diseases of term neonates. A multi-center prospective cohort study including pregnancies with PROM at term with a single fetus were conducted. Time thresholds of the duration from PROM to delivery were examined in 2-h increments to assess the rates of infectious neonatal diseases. 7019 pregnancies were included in the study. Neonatal pneumonia and sepsis were most frequent infectious diseases in neonates born from mother with PROM at term. Rates of early-onset pneumonia varied significantly when comparing length of time of PROM greater than 16 h vs. less than 16 h (for EOP in 3 days of life, adjusted OR 1.864, 95% CI 1.159 ~ 2.997, p = 0.010; for EOP in 7 days of life, adjusted OR 1.704, 95% CI 1.104 ~ 2.628, p = 0.016). Neonates born from mother of whom the length of time from PROM to delivery ≥ 16 h were at a higher risk of acquiring EOP.

Causes of severe neonatal hyperbilirubinemia: a multicenter study of three regions in China.

BACKGROUND: Available evidence suggests that our country bear great burden of severe hyperbilirubinemia. However, the causes have not been explored recently in different regions of China to guide necessary clinical and public health interventions. METHODS: This was a prospective, observational study conducted from March 1, 2018, to February 28, 2019. Four hospitals in three regions of China participated in the survey. Data from infants with a gestational age ≥ 35 weeks, birth weight ≥ 2000 g, and total serum bilirubin (TSB) level ≥ 17 mg/dL (342 µmol/L) were prospectively collected. RESULTS: A total of 783 cases were reported. Causes were identified in 259 cases. The major causes were ABO incompatibility (n = 101), glucose-6-phosphate dehydrogenase deficiency (n = 76), and intracranial hemorrhage (n = 70). All infants with glucose-6-phosphate dehydrogenase deficiency were from the central south region. Those from the central south region had much higher peak total bilirubin levels [mean, 404 µmol/L; standard deviation (SD), 75 µmol/L] than those from the other regions (mean, 373 µmol/L; SD, 35 µmol/L) (P < 0.001). CONCLUSIONS: ABO incompatibility was the leading cause in the east and northwest regions, but cases in the central south region were mainly caused by both ABO incompatibility and glucose-6-phosphate dehydrogenase deficiency, and infants in this region had a much higher peak total bilirubin level. Intracranial hemorrhage may be another common cause. More thorough assessments and rigorous bilirubin follow-up strategies are needed in the central south region.

The correlation between prelabour rupture of the membranes and neonatal infectious diseases, and the evaluation of guideline implementation in China: a multi-centre prospective cohort study.

BACKGROUND: The aim of this study was to describe the epidemiology of prelabour rupture of membranes (PROM) in China and to assess the association between clinical practice following the guidelines and early neonatal infections. METHODS: We conducted a prospective cohort study of 15926 deliveries in ShenZhen Baoan Women's and Children's Hospital, Xibei Women's and Children's Hospital and Chengdu Women's and Children's Hospital between August 1, 2017, to March 31, 2018. Clinical data were collected for each participant. The epidemiology of PROM was described. The association between PROM with early neonatal infectious outcomes and the influence of the implementation of the guideline on early neonatal infectious outcomes were assessed. FINDINGS: The incidence of PROM was 18•7%. PROM was showed to be a risk factor for neonatal infectious diseases (adjusted OR 1•92, 95%CI 1•49~2•49, p<0•0001), early-onset pneumonia (EOP) (adjusted OR 1•81, 95%CI 1•29~2•53, p=0•0006) and early-onset sepsis(EOS) (adjusted OR 14•56, 95%CI 1•90~111•67, p=0•01) for term neonates. For term neonates born from mother with PROM, induction of labor according to the guideline was a protective factor for neonatal diseases(adjusted OR 0•50, 95%CI 0•25~1•00, p=0•00498) and EOP(adjusted OR 0•32, 95%CI 0•11~0•91, p=0•03). For preterm neonates born from mother with PROM, using antibiotics according to the guideline showed to be protective for neonatal infectious diseases (adjusted OR 0•14, 95%CI 0•09~0•23, p<0•0001) and EOP (adjusted OR 0•08, 95%CI 0•04~0•14, p<0•0001). INTERPRETATION: Our study showed the risk of PROM for infectious diseases (including EOP and EOS) and the benefit of the usage of antibiotics according to the guideline for infectious diseases and EOP for preterm neonates. FUNDING: National Natural Science Foundation of China, Capital Medical Development Research Fund of Beijing.

[A clinical analysis of bacterial meningitis in full-term and preterm infants].

OBJECTIVE: To study the clinical features and prognosis of bacterial meningitis in full-term and preterm infants. METHODS: A retrospective analysis was performed for the clinical data of 102 neonates with bacterial meningitis. According to the gestational age, they were divided into a preterm group (n=46) and a full-term group (n=56). The two groups were compared in terms of clinical manifestations, laboratory markers, imaging findings, and clinical outcomes. RESULTS: Poor response and apnea were the major clinical manifestations in the preterm group (P<0.05), while pyrexia and convulsions were more common in the full-term group (P<0.05). The full-term group had a significantly higher glucose level in cerebrospinal fluid (CSF) than the preterm group (P<0.05). Compared with the full-term group, the preterm group had significantly higher C-reactive protein level, positive rate of blood culture, and incidence rate of poor prognosis (P<0.05). There were no significant differences between the two groups in leukocyte count in peripheral blood, levels of leukocytes and protein in CSF, and positive rate of CSF culture (P>0.05). CONCLUSIONS: There are certain differences in the clinical manifestations between full-term and preterm infants with bacterial meningitis. Preterm infants tend to have a higher incidence rate of poor prognosis.

[Clinical effect of exogenous pulmonary surfactant in the treatment of severe neonatal infectious pneumonia: a multicenter prospective clinical trial].

OBJECTIVE: To study the clinical effect of calsurf, a domestic exogenous pulmonary surfactant, in the treatment of severe neonatal infectious pneumonia. METHODS: A total of 208 neonates with severe infectious pneumonia who hospitalized in 5 hospitals of China were enrolled. According to their parents' wishes on admission, these neonates were administered with conventional treatment (control group; n=81) and calsurf treatment + conventional treatment (calsurf treatment group, n=127). The two groups were compared in terms of the degree of oxygen dependence on admission, blood gas parameters before and after treatment, lung ultrasound results, duration of mechanical ventilation, length of hospital stay, hospital costs, complications and prognosis. RESULTS: Compared with the control group on admission, the calsurf treatment group had significantly higher inhaled oxygen concentration and partial pressure of carbon dioxide and significantly lower arterial partial pressure of oxygen and oxygenation index (P<0.01). After 1 hour of treatment, both groups had significant improvements in the above indices (P<0.05), and the improvements were more significant in the calsurf treatment group (P<0.05). After 4-6 hours of calsurf administration, there was a significant reduction in the degree of pulmonary consolidation. The calsurf treatment group had significantly shorter duration of mechanical ventilation and length of hospital stay than the control group, while there was no significant difference in the incidence rate of complications between the two groups. The neonates of both groups had a good prognosis. CONCLUSIONS: In neonates with severe infectious pneumonia, calsurf treatment can significantly improve oxygenation, reduce the degree of pulmonary consolidation, and shorten the duration of mechanical ventilation and length of hospital stay. Therefore, it should be considered in neonates with severe infectious pneumonia.

Pregnancy induced hypertension and outcomes in early and moderate preterm infants.

OBJECTIVE: To identify the effect of pregnancy induced hypertension on neonatal outcomes in early and moderate preterm infants of gestational age less than 34 weeks. STUDY DESIGN: Prospectively collected data in 773 premature deliveries less than 34 weeks from 10 centers in China between July 2014 and July 2016 were analyzed in this cohort study. Univariate and Multivariate regression analyses were conducted to exam the effect of pregnancy induced hypertension on neonatal outcomes, including mortality to discharge, intrauterine growth restriction, severe brain injury, neonatal respiratory distress syndrome, bronchopulmonary dysplasia, necrotizing enterocolitis, early onset of sepsis and retinopathy of prematurity. RESULTS: The incidence of PIH in this cohort was 18.4%. Women with PIH tended to have a higher cesarean delivery rate (78.2% vs 40.9%, P < 0.001). More tocolytics and magnesium sulfate were used in PIH women (72.5% vs 48.7%, P < 0.001; 59.2% vs 34.7%, P < 0.001). Mean birth weight was lower in infants of PIH mothers than infants of non-PIH mothers (1522.1 ±â€¯348.8 g vs 1683.4 ±â€¯345.3, P < 0.001). In multivariate regression models, PIH was associated with increased risk of IUGR (OR 8.402; 95% CI 4.350-16.227) and lower odds of NRDS (OR 0.526; 95% CI 0.332-0.853). CONCLUSION: Preterm infants less than 34 weeks born to PIH women had a higher risk of intrauterine growth restriction and lower birth weight. PIH warrants more intensive interventions to prevent relevant infant morbidities.

Five-Year Multicenter Study of Clinical Tests of Neonatal Purulent Meningitis.

This study aimed to provide more data support for early diagnosis and treatment of neonatal purulent meningitis through retrospective analysis of its clinical diagnosis and treatment, pathogen distribution, and drug resistance in 5 third-class A hospitals in Southwest and Northwest China from January 2011 to December 2015. It was found that both the positive rates of blood and cerebrospinal fluid culture were low, and Escherichia coli should be the main pathogenic bacteria. Drug-resistant strains with varying degrees to the third generation of cephalosporin antibiotics have appeared currently.

[Impact of premature rupture of membranes on neonatal complications in preterm infants with gestational age <37 weeks].

OBJECTIVE: To investigate the effect of premature rupture of the membrane (PROM) on neonatal complications in premature infants. METHODS: The registration information of 7684 preterm infants with gestational age <37 weeks were collected from the cooperative units in the task group between January 1, 2014 to December 31, 2014. Specially trained personnel from each cooperative units filled in the unified form in a standardized format to record the gender, gestational age, birth weight, PROM, placental abruption, antenatal corticosteroid, Apgar score, amniotic fluid pollution, and complications of the infants. The data were analyzed comparatively between the cases with PROM and those without (control). RESULTS: The preterm mortality rate was significantly lower but the incidences of ICH, NEC, ROP and BPD were significantly higher in PROM group than in the control group (P<0.05). The 95% confidence interval of the OR value was <1 for mortality, and was >1 for ICH, NEC, ROP and BPD. After adjustment for gestational age, birth weight, gender, mode of delivery, placental abruption, placenta previa, prenatal hormones, gestational diabetes mellitus (GDM), gestational period hypertension and 5-min Apgar score <7, the incidences of NEC, ROP and BPD were significantly different between the two groups (P<0.05) with 95% confidence interval of OR value >1, but the mortality rate and incidence of ICH were not significantly different between the two groups (P>0.05). CONCLUSION: PROM is a risk factor for NEC, ROP and BPD in preterm infants, and adequate intervention of PROM can reduce the incidences of such complications as NEC, ROP and BPD in the infants.

[Efficacy of different preparations of budesonide combined with pulmonary surfactant in the treatment of neonatal respiratory distress syndrome: a comparative analysis].

OBJECTIVE: To study the efficacy of different preparations of budesonide combined with pulmonary surfactant (PS) in improving blood gas levels and preventing bronchopulmonary dysplasia (BPD) in preterm infants with neonatal respiratory distress syndrome (NRDS). METHODS: A total of 184 preterm infants who developed NRDS within 4 hours after birth were randomly administered with PS + continuous inhalation of budesonide aerosol (continuous aerosol group), PS+budesonide solution (solution group), PS + single inhalation of budesonide aerosol (single aerosol group), and PS alone, with 46 neonates in each group. The changes in arterial blood gas levels, rate of invasive mechanical ventilation after treatment, time of assisted ventilation, rate of repeated use of PS, and the incidence of BPD were compared between the four groups. RESULTS: On the 2nd to 4th day after treatment, pH, PCO2, and oxygenation index (FiO2/PaO2) showed significant differences among the four groups, and the continuous aerosol group showed the most improvements of all indicators, followed by the solution group, single aerosol group, and PS alone group. The continuous aerosol group had a significantly shorter time of assisted ventilation than the other three groups (P<0.05). The solution group had a significantly shorter time of assisted ventilation than the single aerosol and PS alone groups (P<0.05). The rate of invasive mechanical ventilation after treatment, rate of repeated use of PS, and incidence of BPD showed significant differences among the four groups (P<0.05), and the continuous aerosol group had the lowest rates, followed by the solution group. CONCLUSIONS: A combination of PS and continuous inhalation of budesonide aerosol has a better efficacy in the treatment of NRDS than a combination of PS and budesonide solution. The difference in reducing the incidence of BDP between the two administration methods awaits further investigation with a larger sample size.

[Dose-effect relationship between androgen and neural protection in neonatal rats with hypoxic-ischemic brain damage and adverse effects of androgen].

OBJECTIVE: To explore brain-protective effect of androgen, its dose-effect relationship and long-term adverse reaction. METHOD: Seventy two 3-day-old SD rats were randomized into androgen group (n = 32), HIBD model group (n = 32) and sham operated group (n = 8). The androgen group and HIBD model group were further randomized into 30 mg/kg group, 60 mg/kg group, 120 mg/kg group and 240 mg/kg group, respectively. In androgen group and HIBD group, every rat was given testosterone or peanut oil, one time a day. Three days later, HIBD model was established by occlusion of the left common carotid artery and inhalation of 8% oxygen plus 92% nitrogen for 2.5 hours. Adult rats' ability of learning and memory was determined by water maze test. Escape latencies were recorded and analyzed by statistics. Vaginal cells of all female rats were examined everyday for identifying their estrous cycle. Female rats were allowed to live with normal adult male rats if the female rats were in estrous period. Vaginal cells were examined everyday until sperm was seen, which was the signal of gestation. Pregnancy rate and the number of embryos were recorded and analyzed by statistics. Acropetal coefficient was calculated. The testes and epididymis were taken from adult male rats, histopathological sections were made, and the structure of testis and epididymis were studied under light microscope. RESULT: In Morris experiment, escape latencies (EL) of HIBD group were much longer than those of sham operation group (27.71 ± 3.19) s, time of first enter target (1(st) ET) was later than that of sham operation group (5.34 ± 0.83) s, times of target cross (TC) was less than that of sham operation group (18.88 ± 1.89) (P < 0.01, P = 0.0005). EL of androgen group (34.89 ± 3.68, 33.71 ± 3.38, 33.84 ± 3.45, 35.43 ± 2.43) were much shorter than that of HIBD group, 1(st) ET (5.39 ± 1.51, 6.28 ± 2.07, 5.09 ± 1.61, 5.85 ± 0.87) was earlier than that of HIBD group, TC (12.75 ± 2.05, 14.88 ± 3.36, 14.88 ± 2.36, 14.38 ± 1.60) was more than that of HIBD group (P < 0.01, P = 0.0001). Among the four doses groups of androgen group, EL, 1(st) ET and TC had no statistical significance (P > 0.05, P = 0.159). There were no statistical significance between male rats of androgen group [Testes acropetal coefficient (0.89 ± 0.07, 0.92 ± 0.08, 0.88 ± 0.11, 0.87 ± 0.09), epididymis acropetal coefficient (0.25 ± 0.02, 0.24 ± 0.05, 0.26 ± 0.04, 0.23 ± 0.05)], HIBD group and sham operation group (P > 0.05, P = 3.207). Among the four doses groups of androgen group had no statistical significance (P > 0.05, P = 6.663). There were no statistical significance between female rats of androgen group (pregnancy rate, 100%; times, 14.52 ± 3.34, 14.69 ± 2.28, 14.98 ± 2.67, 15.38 ± 3.07), HIBD group and sham operation group in pregnancy rate and times. CONCLUSION: The intellectual ability of rats decreased after HI. Androgen could reduce the effect of HI on intellectual ability. Androgen had no adverse reaction to the reproductive capacity of adult rats.

Effects of androgen on the expression of brain aromatase cytopigment and nerve growth factor in neonatal rats with hypoxic-ischemic brain damage.

OBJECTIVE: To study the effects of androgen on the expression of aromatase cytopigment P450 (AROM) and nerve growth factor (NGF) in the brain and brain ultrastructure in neonatal rats with hypoxic-ischemic brain damage (HIBD) in order to investigate the mechanism underlying the protective effect of androgen against HIBD. METHODS: Ninety-six seven-day-old Sprague-Dawley rats were randomly divided into three groups: sham-operation, HIBD and androgen treatment (n=32 each). HIBD was induced by the ligation of left common carotid artery and hypoxia exposure. The rats in the androgen treatment and the HIBD groups were injected intraperitoneally with testosterone propionate (25 mg/kg) and arachis oil respectively immediately after hypoxia-ischemia (HI). After 24 and 72 hrs and 7 and 10 days of HI, AROM and NGF expression in the cortex and the hippocampus was detected with the immunohistochemical method. The ultrastructural changes of neurons in the cortex and the hippocampus were observed under a transmission electron microscope. RESULTS: Nerve cells of the HIBD group showed obvious injuries including cell organ decreasing, cellularoedema, nuclear swelling, chromatic agglutination, mitochondria decreasing and swelling, as well as an increase in apoptotic cells. Compared with the HIBD group, the nerve cells in the androgen treatment group had integrated nuclear membrane, well-distributed chromatin and abundant cell organs, and less cell apoptosis and increased axon regeneration. There was a positive expression of NGF and AROM in the brain cortex and the hippocampus in the HIBD group 24 hrs after HI. The expression of NGF and AROM increased significantly 72 hrs after HI, peaked 7 days after HI and then began to decrease but remained at a higher level than that in the sham-operation group 10 days after HI. The NGF and AROM expression in the cortex and the hippocampus in the androgen treatment group was significantly higher than that in the sham-operation and the HIBD groups 72 hrs, and 7 and 10 days after HI. CONCLUSIONS: Androgen treatment can promote axon regeneration and morphous recovery of neurons and decrease neural apoptosis in neonatal rats with HIBD. The neuroprotection of androgen is produced possibly through an increase in the expression of NGF and AROM in the brain.

[Effects of androgen on phosphacan and NG2 proteoglycan expression and neurite regeneration in neonatal rats with hypoxic-ischemic brain damage].

OBJECTIVE: To study the effects of androgen on the expression of phosphacan and NG2 proteoglycan (NG2) and neurite regeneration in neonatal rats with hypoxic-ischemic brain damage (HIBD) and the potential mechanism underlying the protective effect of androgen against HIBD. METHODS: One hundred and twenty neonatal Sprague-Dawley rats were randomly divided into three groups: sham-operated, HIBD and androgen treatment. HIBD was induced by the ligation of left common carotid artery and hypoxia exposure. The androgen treatment group rats were injected with testosterone propionate (25 mg/kg) immediately after HIBD. Phosphacan and NG2 expression in the cortex and the hippocampus was detected with the immunohistochemical method 24 and 72 hrs and 7 and 10 days after hypoxia-ischemia (HI). The ultrastructure and neurite regeneration of neurons in the cortex and the hippocampus were observed under a transmission electron microscope. RESULTS: The neurite regeneration was obvious in the sham-operated group, but seldom in the HIBD group. The androgen treatment group showed increased neurite regeneration compared with the HIBD group. There were fewer phosphacan and NG2 positive cells in the cortex and the hippocampus in the sham-operated group. Phosphacan and NG2 expression in the cortex and the hippocampus was observed at 24 hrs, increased at 72 hrs, and peaked at 7 days after HI in the HIBD group and remained at a higher expression 10 days after HI than in the sham-operated group. The levels of phosphacan and NG2 expression in the cortex and the hippocampus in the androgen treatment group were significantly reduced compared with those in the HIBD group 24 and 72 hrs and 7 and 10 days after HI (P<0.01). CONCLUSIONS: Phosphacan and NG2 may be important inhibitory factors for neurite regeneration following HIBD in neonatal rats. The neuroprotection of androgen against neonatal HIBD is produced possibly through an inhibition of phosphacan and NG2 expression.