Maturation and development of fetal pig intestinal tissue in immunodeficient mice

Purpose: This study aimed to compare the degree of maturation and development of fetal pig segmental intestinal tissue with that of spheroids created by in-vitro reaggregation of dissociated fetal intestinal cells after transplantation into immunodeficient mice. Methods: Fetal pig small intestines were transplanted as segmental grafts into the omentum and subrenal capsules of immunodeficient mice or enzymatically treated to generate single cells. Spheroids made by in-vitro reaggregation of these cells were transplanted into the subrenal capsules of immunodeficient mice. The segmental grafts and spheroids were harvested four and eight weeks after transplantation, and the structural maturity and in-vivo development of these specimens were histologically evaluated. Results: The spheroids were engrafted and supplied blood vessels from the host mice, but an intestinal layered structure was not clearly observed, and there was almost no change in size. On the other hand, the segmental grafts formed deep crypts in the mucus membrane, the inner circular layer, and outer longitudinal muscles. The crypts of the transplanted grafts harvested at eight weeks were much deeper, and the smooth muscle layer and the enteric nervous system were more mature than those of grafts harvested at the fourth week, although the intestinal peristaltic wave was not observed. Conclusions: Spheroids created from fetal small intestinal cells could not form layered structures or mature sufficiently. Conversely, segmental tissues structurally matured and developed after in-vivo transplantation and are therefore potential grafts for transplantation.

Progress on effect of vitamin D on fetal and neonatal lung development and its mechanism / 中华围产医学杂志

The role and mechanism of vitamin D in fetal and neonatal lung development and chronic lung diseases development have raised attention in recent years. The placental transfer of vitamin D is the major source of vitamin D to the developing fetus. The lung, as a target organ for vitamin D, has its capacity for vitamin D metabolism and can form biologically active 1,25 dihydroxyvitamin D 3 in a paracrine manner to regulate lung development. Studies have shown that vitamin D is directly involved in the synthesis of lung surfactant proteins and phospholipids and promotes lung maturation such as lung epithelial-mesenchymal interactions and alveolar formation. Furthermore, it regulates immunity and improves placental function, which indirectly affects lung development. Vitamin D deficiency and vitamin D receptor polymorphisms have been found to be detrimental to the development of alveoli, and are associated with respiratory diseases such as neonatal respiratory distress syndrome and bronchopulmonary dysplasia (BPD). Experimental studies in animals have shown that antenatal vitamin D supplementation promotes lung maturation in preterm rats and postnatal vitamin D supplementation can alleviate the hyperoxia-induced inflammatory response in the lung and reduce BPD occurrence. Further high-quality research are needed to explore the dosing, timing, and impact factors of vitamin D for promoting fetal and neonatal lung maturation and clarify the mechanism of its prophylactic and therapeutic action.

Discussion on prenatal corticosteroids for fetal lung maturation / 中华围产医学杂志

Prenatal corticosteroid for fetal lung maturation has been widely used in daily practice in obstetrics. However, previous research showed that prenatal corticosteroids may increase the risk of neonatal hypoglycemia and birth weight loss. And it remains controversial regarding the dosage and repeated administration. Based on the guideline "Antenatal corticosteroids to reduce neonatal morbidity and mortality" published by Royal College of Obstetricians and Gynaecologists in February 2022, here we are going to discuss several issues on the usage of prenatal corticosteroids.

Effects of histologic chorioamnionitis induced by lipopolysaccharide intra-amniotic injection on fetal lung maturation and development in preterm fetal rats / 中华围产医学杂志

Objective With various doses of lipopolysaccharide (LPS) intra-amniotic injection in pregnant rats to establish histologic chorioamnionitis (HCA) model,and to determine the effects of HCA on fetal lung maturation and development in preterm fetal rats.Methods Thirty pregnant Sprague-Dawley rats were randomly assigned to four groups.On 19 days of gestation,rats in three model groups (n=8) were given intra-amniotic injection of LPS 2,8,10 μg,respectively,and those in the only one control group (n=6)was given normal saline (NS) 40 μl.Fetal rats were taken out 48 hours after LPS injection.Placenta,fetal membrane,fetal lung and umbilical cord were collected for pathological examination.mRNAs of surfactant protein (SP)-A,B and C and keratinocyte growth factor (KGF) in lung were determined by quantitative real-time polymerase chain preaction.KGF protein expression in lung was measured by immunohistochemistry.Morphologic observation of lung was performed on postnatal day 3.R× C table Chi-square test,KruskalWallis test and analysis of variance were used as statistical methods.Results (1) Fetal rat mortality in control,LPS2,LPS8 and LPS10 group was 0.0％ (0/55),22.5％ (18/80),51.4％ (36/70) and 87.5％(35/40),respectively,which increased with increasing dose of LPS (x2=46.183,P＜0.005).(2) HCA,fetal lung inflammation and umbilical vasculitis were induced in LPS groups,and the severity was dosedependent (fetal lung inflammation:Hc=39.84,HCA:Hc=41.13,umbilical vasculitis:Hc=41.52,all P＜0.01).(3) The expression of SP-A,SP-B,SP-C and KGF mRNAs in the four groups (control,LPS2,8,10) had statistical differences (SP-A mRNA:0.99±0.28,2.48±0.34,1.09±0.31 and 0.09±0.09,F=78.051; SP-B mRNA:0.99±0.34,2.23±0.53,1.49±0.51 and 0.14±0.06,F=28.327; SP-C mRNA:1.20±0.39,2.00±0.20,1.04±0.37 and 0.12±0.16,F=39.546; KGF mRNA:0.97±0.19,2.18±0.61,0.93±0.09 and 0.21±0.11,F=37.544; all P＜0.01).All mRNA expressions in LPS2 group were higher than those in the control group and those in LPS10 group was lower (all P＜0.05).(4) The expression of KGF protein in LPS2 group was significantly higher than that in other groups (0.60±0.20 vs 0.28±0.12,0.37±0.22,0.24±0.12,F=17.280,all P＜0.01).(5) Alveolarization was significantly inhibited in LPS8 group on postnatal day 3,and less maturity of pulmonary tissue was observed.Conclusions Various doses of LPS intra-amniotic injection in rats could induce HCA,fetal lung inflammation and umbilical vasculitis with different degrees.Histological inflammation would be worse with increasing LPS dosage.Moderate inflammation could promote lung maturation without inducing bronchopulmonary dysplasia,and KGF may play a role in this process.

Comparison of effects of prenatal administration of dexamethasone and ambroxol on expression of Toll-like receptor 4 of fetal and neonatal rats / 中华围产医学杂志

Objective To investigate the role of prenatal single-dose administration of dexamethasone and ambroxol on the expression of Toll-like receptor 4 (TLR4) of fetal and neonatal rats. Methods Fifty-four pregnant rats were randomly divided into three groups with eighteen rats in each group:rats treated with 0.2 mg/kg dexamethasone (group 1),0.2 mg/kg dexamethasone and 100 mg/kg ambroxol (group 2),or saline(controls) on the 17th day of gestation.The lung tissues of the offsprings were harvest independently on the 19th day of gestation,the postnatal 3 days and 7 days.The expressions of TLR4 in fetal/neonatal rat lungs of each pregnant rat were analyzed by reverse transcription-polymerase chain reaction(RT-PCR),immunohistochemistry stain,and Western blot. ANOVA and two independent samples t-test were applied. Results On the 19th day of pregnancy,TLR4 mRNA expression was up-regulated in lungs of the two treatment groups compared with controls(controls:0.26 ± 0.18,group 1:0.39 ± 0.21,t =5.866,P＜ 0.05 ; control:0.27 ± 0.22,group 2:0.46 ± 0.13,t =9.572,P＜ 0.01 ).TLR4 mRNA expression was up-regulated in group 2 compared with controls on the postnatal 3 days and 7 days(postnatal 3 d:0.59 ± 0.23 and 0.47 ±0.24,t=2.295,P＜0.05;postnatal 7 d:0.52±0.12 and 0.35±0.17,t=4.219,P＜0.05),while no significant difference was found in group 1 compared with the controls(postnatal 3 d:0.45±0.22 and 0.44±0.14,t=0.128,P＞0.05; postnatal 7 d:0.40±0.16 and 0.36 ±0.12,t=1.365,P＞0.05).Results of the immunohistochemistry demonstrated that on the 19th day of pregnancy,the protein expression of TLR4 was significantly increased in the two treatment groups (controls:0.20 ± 0.29,group 1:0.35±0.32,t=7.179,P＜0.05 ;controls:0.20±0.29,group 2:0.39±0.25,t=10.764,P＜0.01).The protein expression of TLR4 was significantly increased in group 2 on the postnatal 3 days and 7 days(postnatal 3 d:0.55±0.32 and 0.37±0.18,t=7.121,P＜0.05;postnatal 7 d:0.41±0.29and 0.25±0.24,t=6.355,P＜0.05),while no notable difference was found between group 1 and the control (postnatal 3 d:0.40±0.21 and 0.37±0.18,t=0.683,P＞0.05 ;postnatal 7 d:0.28±0.31 and 0.25±0.24,t=0.462,P＞0.05).Results of the Western blot demonstrated that on the 19th day of pregnancy,the protein expression of TLR4 was significantly increased in the two treatment groups (controls:0.15 ± 0.12,group 1:0.27± 0.20,t =7.835,P＜0.05; controls:0.16 ± 0.18,group 2:0.34±0.16,t=10.470,P＜0.01).The protein expression of TLR4 was significantly increased in lungs of the combination administration group on the postnatal 3 days and 7 days(postnatal 3 d:group 2:0.37±0.20 and 0.25±0.22,t=6.379,P＜0.05; postnatal 7 d:0.35±0.15 and 0.24±0.13,t=5.152,P＜0.05),while no notable difference could be found between group 1 and the control (postnatal3 d:0.32±0.26 and 0.25±0.16,t=1.167,P＞0.05; postnatal 7 d:0.29±0.19 and 0.24±0.10,t =1.248,P ＞ 0.05 ). Conclusions Prenatal single-dose administration of dexamethasone may up-regulate the expression of TLR4 in the rat fetal lung.The up-regulation of TLR4 might be one of the critical factors for glucocorticoid-induced maturity of fetal lung.Prenatal single-dose administration of dexamethasone and ambroxol may have effects on the regulation of TLR4 not only in fetal rats,but also in neonatal rats.

Avaliação da maturidade pulmonar fetal pela contagem dos corpos lamelares no líquido amniótico / Evaluation of fetal lung maturity by lamellar bodies counting in amniotic fluid

Objetivo: comparar o teste de contagem de corpos lamelares (CCL) no líquido amniótico com o teste da polarização fluorescente (PF) como parâmetro diagnóstico para avaliação da maturidade pulmonar fetal. Método: estudo transversal, analítico e controlado realizado com 60 gestantes atendidas no período de março de 2002 a dezembro de 2007. Foram colhidas amostras de líquido amniótico e realizados os testes de CCL e PF (TDxFLM II), considerados de referência, e comparados à presença ou ausência da Síndrome do Desconforto Respiratório (SDR). Foram estabelecidos valores de corte para maturidade de 30 mil corpos lamelares/µL para o teste da CCL e 55 mg/g de albumina para o PF. Foram avaliadas as características maternas e perinatais, a evolução neonatal e o desempenho dos testes diagnósticos para predição da maturidade pulmonar fetal. Na análise estatística, foram utilizadas medidas descritivas e calculados os valores referentes à sensibilidade, especificidade, valor preditivo positivo e negativo dos testes, considerando-se significativos valores de p<0,05. Resultados: a idade materna variou entre 15 e 43 anos, com média de 26,6 anos. A idade gestacional variou entre 24,3 e 41,6 semanas, com média de 35,1 semanas. A Síndrome do Desconforto Respiratório foi diagnosticada em 13,3 por cento dos neonatos. As características perinatais, como peso, índice de Apgar, incidência de SDR, foram comparadas aos resultados dos testes de CCL e PF, sendo observada uma correspondência, estatisticamente significativa (p<0,05), entre os grupos de neonatos clinicamente classificados como imaturos e maduros em ambos os testes. Os testes foram concordantes em 68,3 por cento dos casos. Quando se comparou o teste da PF com o teste da CCL, a sensibilidade foi de 100 por cento para ambos, e a especificidade do teste da CCL foi superior (73,1 por cento), quando comparado com o teste de PF (51,9 por cento). O padrão-ouro para determinação da maturidade fetal é a ocorrência da SDR. O valor...

Purpose: to compare the lamellar body number density (LBND) count in amniotic fluid using the fluorescent polarization (FP) test as a diagnostic parameter for the assessment of fetal pulmonary maturity. Method: this was an analytical, controlled cross-sectional study conducted on 60 pregnant women from March 2002 to December 2007. Amniotic fluid specimens were obtained by amniocentesis or at the time of caesarean section, and submitted to the LBND and FP tests (TDxFLM®, Abbott Laboratories), the latter considered to be a reference test, and compared in terms of the presence or absence of respiratory distress syndrome (RDS). Cut-off values for maturity were established at 30,000 lamellar bodies/µL for the LBND test and 55 mg/g albumin for the FP test. Maternal and perinatal characteristics and neonatal evolution were evaluated, and the performance of the diagnostic tests regarding fetal pulmonary maturity was determined. In the statistical analysis, descriptive measures were used and the sensitivity, specificity and positive and predictive values of the tests were determined with the level of significance set at p<0.05. Results: maternal age ranged from 15 to 34 years (mean: 26.6 years) and gestational age ranged from 24.3 to 41.6 weeks (mean: 35.1 weeks). RDS was diagnosed in 35.1 percent of neonates. Perinatal characteristics such as weight, Apgar score, and RDS incidence were compared to the results of the LBND and FP tests and a significant correspondence (p<0.05) was observed between the groups of neonates clinically classified as mature and immature in both tests. The tests were concordant in 68.3 percent of the cases. Comparison of the PF and LBND tests revealed 100 percent specificity for both and a higher specificity for the LBND test (73.1 percent as opposed to 51.9 percent for the PF test). The gold standard for the determination of fetal maturity is the occurrence of RDS. The positive predictive value of the LBND test was higher (36.4%) than that...

MRI quantitative assessment of brain maturation and prognosis in premature infants using total maturation score / 中华放射学杂志

o statistical difference between WMD group and control group (t = 1.83, t = 0. 88, P 0. 05). Conclusion Conventional MRI is able to quantify the brain maturation and prognosis of premature infants using TMS.

Study on the contrast of diagnosis value of two-dimensional and three-dimensional sonography on the fetal facial structure / 中国基层医药

Objective Study on the clinic value of the application of two-dimensional and three-dimensional sonography on observing the fetal facial structure. Methods Applying Voluson 730 three-dimensional probe surface imaging mode and two-dimensional probe to make sonography on 16～48 weeks fetus in 1805 cases, emphasized on observing the fetal facial structure, saving the image information, making three-dimensional reconstruction and comparing the result of post partum and the result after induction of labor. Results In 1805 cases, applying two-dimensional and three-dimensional sonography to observe the facial structure of the fetus of 23～35 weeks, the display rate is 93.1% and 95.1% respectively, and there is no obvious difference between the two modes. The three-dimensional is higher than two-dimensional for the fetus less than 23 weeks, with the display rate 69.6% and 84.8% respectively, and the two-dimensional is a bit higher than three-dimensional for the fetus more than 35 weeks, with the display rate 90.4% and 88.7% respectively. One cleft lip case is excluded. Conclusion As long as mastering the optimum examination time and operation skill, there is no obvious difference between the display rate of two-dimensional and three-dimensional sonography on observing the fetal facial structure, the two modes can be complementary in the work to improve the accuracy of the diagnosis and be favorable for the prepotency.

Count of Amnionic Fluid Lamellar Body to Predict the Maturity of Fetal Lung / 中华围产医学杂志

Objective To discuss the value of amnionic fluid lamellar body count(LBC) as a predictor of fetal lung maturity. Methods Amnionic fluid was obtained during the cesarean section of 41 normal term pregnancies. LBC was performed on each specimen, and lecithin-sphingomyelin(L/S) ratio was detected simultaneously. Results (1)Amnionic fluid LBC was (86?43)?10 3 (72.5?10 3~99.4?10 3) in normal term pregnancy. (2) Positive correlation was shown between the amnionic fluid LBC and L/S ratio(r=0.66,P=0.001). Conclusion The LBC is a rapid and accurate method to determine the fetal lung maturity.