Genome-wide microRNA expression profiling in placentas of fetuses with Down syndrome.

INTRODUCTION: Down syndrome (DS) is the most common aneuploidy, caused by an extra copy of all or part of chromosome 21 (chr21). Differential microRNA (miRNA) expression is involved in many human diseases including DS. However, the genome-wide changes in miRNA expression in DS fetal placentas have yet to be determined, and the function of these changes is also unclear. METHODS: We profiled genome-wide miRNA expression in placenta samples from euploid or DS fetuses by using microarray technology and predicted the functions of differentially expressed miRNAs using bioinformatics tools. RESULTS: Thirty-four miRNAs were significantly differentially expressed in the DS placenta compared with the normal placenta (16 up-regulated and 18 down-regulated). However, expression of chr21-derived miRNAs did not change. Predicted target genes included 7434 genes targeted by up-regulated miRNAs and 6071 genes targeted by down-regulated miRNAs. Seventy-six of these target genes were located on chr21 (10 genes controlled by down-regulated miRNAs and 34 genes by up-regulated miRNAs, and 32 genes by both). Target genes on chr21 were significantly associated with DS and DS-related disorders, such as mental retardation, neurobehavioral manifestations, and congenital abnormalities. DISCUSSION: To our knowledge, this is the first genome-wide study to comprehensively survey placental miRNAs in DS fetuses. Our results provide new insight into miRNA expression in placentas of fetuses with DS. Additionally, our findings indicate that the differentially expressed miRNAs in the DS placenta may potentially affect various pathways related to DS pathogenesis.

Foetal and neonatal outcomes in first-trimester pregnant women exposed to abdominal or lumbar radiodiagnostic procedures without administration of radionucleotides.

BACKGROUND/AIM: Little is known about exposures to low radiation doses in the first trimester of pregnancy and deterministic adverse effects in the offspring, and risks are extrapolated from catastrophic events or from exposures to radiotherapy. The study aimed to assess the foetal and neonatal outcomes of pregnant women exposed to radiodiagnostic procedures with abdominal or lumbar irradiation. METHODS: In a prospective cohort design, we studied the foetal and neonatal outcomes in 115 singleton pregnant women who required abdominal or lumbar radiodiagnostic procedures without the administration of radionucleotides, and in 527 age-matched (± 2 years) control pregnant women. RESULTS: In the exposed group, lumbar spine radiography (33.9%), plain abdominal radiography (16.5%) and upper gastrointestinal tract radiography with abdominal irradiation (15.7%) were the most common radiodiagnostic procedures. Major congenital malformations were identified in two (1.9%) babies born in the exposed group and in two (0.4%) babies born in the control group (odds ratio = 4.7; 95% confidence interval 0.7-33.6; P = 0.15). The rest of the foetal and neonatal outcomes was similar in the two groups except by a marginally higher rate of admissions to the neonatal intensive care unit among babies born to exposed women (odds ratio = 2.9; 95% confidence interval 1.0-9.4; P = 0.06). CONCLUSION: Our results indicate that X-ray and computed tomography scan exposure involving abdominal irradiation without the administration of radionucleotides is not associated with adverse foetal and neonatal deterministic outcomes. Efforts are required to reduce the use of radiodiagnostic procedures for general check-ups in childbearing age women.

Association of fetal-derived hypermethylated RASSF1A concentration in placenta-mediated pregnancy complications.

OBJECTIVES: To assess whether fetal-derived hypermethylated RASSF1A concentrations in maternal plasma during pregnancy are altered in pregnancies associated with placental dysfunction manifested by intrauterine growth restriction (IUGR), preeclampsia (PE), or placental previa (PP) and whether this alteration can be detected in susceptible subjects before the onset of clinical disease. METHODS: We performed a real-time quantitative polymerase chain reaction to quantify RASSF1A concentrations before and after methylation-sensitive restriction digestion in maternal plasma at 7-41 gestational weeks of normal pregnancies (n = 161), IUGR (n = 43), PE (n = 22), PP (n = 14) and non-pregnant women (n = 20). RESULTS: A positive correlation was observed between fetal-derived hypermethylated RASSF1A concentration and gestational age for all study groups (r = 0.624, p < 0.001 for IUGR; r = 0.381, p = 0.042 for PE; r = 0.697, p < 0.001 for PP; r = 0.560, p < 0.001 for controls). The concentration of hypermethylated RASSF1A was relatively high at 7-14 gestational weeks in all patient groups. Hypermethylated RASSF1A concentration at 15-28 weeks was significantly higher in patients who subsequently developed IUGR (p = 0.002), PE (p < 0.001) or PP (p < 0.001) than in controls. CONCLUSION: We first demonstrated increased concentration of fetal-derived hypermethylated RASSF1A sequences according to advancing gestation and before the onset of the clinical manifestation of pregnancy complications secondary to placental dysfunction, such as IUGR, PE and PP. Hypermethylated RASSF1A in maternal plasma may be useful as a potential biomarker to detect placental-mediated pregnancy complications, regardless of fetal gender and polymorphism.

Interleukin-18, transforming growth factor-ß, and vascular endothelial growth factor gene polymorphisms and susceptibility to primary glomerulonephritis.

Several studies have showed an association of gene polymorphisms with the development of glomerulonephritis (GN). We investigated the effects of gene polymorphisms on the development of GN by analyzing polymorphisms in the interleukin (IL)-18, transforming growth factor (TGF)-ß, and vascular endothelial growth factor (VEGF) genes in Korean patients with primary GN. The study included 146 normal subjects (controls) and 100 patients diagnosed with primary GN by kidney biopsy. The gene polymorphisms A-607C and G-137C in IL-18, C-509T and T869C in TGF-ß1, and C-2578A and C405G in VEGF were investigated in DNA extracted from peripheral blood. Significant differences were observed between the GN and control groups in the genotype and allele frequencies of A-607C IL-18 and C405G VEGF. The frequencies of the IL-18-607CC genotype [P = 0.001, odds ratio (OR) = 2.473] and the VEGF 405GG genotype (P = 0.001, OR = 2.473) were significantly increased in the GN group. The combination of IL-18-607CC+ and VEGF 405GG+ genotypes had a higher risk for developing GN in comparison with the combination of IL-18-607CC- and VEGF 405GG- genotypes (P < 0.001, OR = 8.642). In the haplotype analysis of the IL-18 gene, the CG haplotype was significantly more frequent in the GN group than the control group (61.5% vs 46.9%, P = 0.002). These results show that the -607CC genotype of the IL-18 gene and the 405GG genotype of the VEGF gene are associated with susceptibility to and the development of primary GN.

Mesenchymal progenitor cells in the human umbilical cord.

Mesenchymal progenitor or stem cells (MPCs) isolated from fetal blood, liver, and bone marrow are a population of multipotential cells that can proliferate and differentiate into multiple mesodermal tissues including bone, cartilage, muscle, ligament, tendon, fat, and stroma. The objective of this study was to isolate and characterize MPCs in the human umbilical cord. The suspensions of endothelial and subendothelial cells in cord vein were collected and cultured in M199 supplemented with 10% fetal bovine serum (FBS). Of 50 umbilical cord samples, 3 had numerous fibroblastoid cells morphologically distinguishable from endothelial cells. Fibroblastic cells displayed lack of expression of vWF, Flk-1, and PECAM-1, indicating the endothelial cell-specific marker. To investigate the differentiation potentials, the cells were cultured in adipogenic or osteogenic medium for 2 weeks. Fibroblast-like cells treated with adipogenic supplementation showed Oil red O-positive staining and expressed adipsin, FABP4, LPL, and PPARgamma2 genes by reverse transcriptase polymerase chain reaction (RT-PCR). In osteogenic differentiation, alkaline phosphatase activity and calcium accumulation were detected. RT-PCR studies determined that Cx43, osteopontin, and Runx2 genes were expressed in the osteogenic cultures. Among three cell lines cultured continuously for passage 10, two had normal karyotypes; however, one retained a karyotype of mos 46,XY[19]/47,XY,+mar[3]. These observations suggest that MPCs are present in human umbilical cord and possess several typical traits of MPCs.

Unusual fate of vesicoallantoic cyst with non-visualization of fetal urinary bladder in a case of patent urachus.

We present the sonographic findings of a fetus with a vesicoallantoic cyst. The cyst was first identified at 17 weeks of gestation; it was associated with an omphalocele, and disappeared spontaneously at 29 weeks. The fetal urinary bladder was not visualized thereafter. An omphalocele and exstrophia of the urachus were found at birth and repaired. Non-visualization of the fetal urinary bladder suggested rupture of the covering membrane of the omphalocele and allantois during fetal life. A defect in the wall of the omphalocele supported our hypothesis.