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Postnatal Growth Retardation (postnatal + growth_retardation)
Selected AbstractsRing chromosome 6 in three fetuses: Case reports, literature review, and implications for prenatal diagnosisAMERICAN JOURNAL OF MEDICAL GENETICS, Issue 2 2002Maik Urban Abstract Prenatal and postnatal findings in three fetuses with a ring chromosome 6 are presented, and the literature of this rare cytogenetic disorder is reviewed. The described fetuses illustrate the broad spectrum of the clinical manifestation of ring chromosome 6. In one fetus, the disorder was diagnosed incidentally by a routine amniocentesis due to advanced maternal age. The other two fetuses were hydrocephalic and had other congenital anomalies. Remarkably, the ring chromosome 6 tends to disappear in cultured amniotic fluid cells; karyotyping revealed complete or nearly complete monosomy 6. In contrast, the ring was preserved in high proportions of fetal leukocytes. Postnatal growth retardation is the only consistent finding of this chromosomal disorder. Maternal age is not significantly above average. An additional review of 20 literature cases revealed a striking tendency to hydrocephalus, either due to deficient brain growth or secondary to an aqueductal stenosis. Children with hydrocephalus and ring chromosme 6 tend to display facial dysmorphism and may have additional malformations, growth failure, eye anomalies, and seizures. In contrast, there are two reports on children with a ring chromosome 6 who had short stature, normal appearance, and a normal or almost-normal psychomotor development. In such patients at the mild end of the clinical spectrum, the phenotype is basically restricted to what Kosztolányi. [1987: Hum Genet 75:174,179] delineated as "ring syndrome," comprising "severe growth failure without major malformations, without a specific deletion syndrome, with only a few or no minor anomalies, and mild to moderate mental retardation." This "ring syndrome" is considered to occur independently of the autosome involved in the ring formation. The overall impression from our cases and from the literature review of cases with ring chromosome 6 is that the karyotype-genotype correlation is poor. This makes prognostic counseling of parents difficult and unsatisfactory. Serial targeted ultrasound examinations, especially of the brain, are decisive factors in elucidating the prognosis. © 2002 Wiley-Liss, Inc. [source] New insights into the development of retinopathy of prematurity , importance of early weight gainACTA PAEDIATRICA, Issue 4 2010A Hellström Abstract Evidence is accumulating that one of the strongest predictors of retinopathy of prematurity (ROP), in addition to low gestational age, is poor weight gain during the first weeks of life. In infants born preterm, the retina is not fully vascularised. The more premature the child, the larger is the avascular area. In response to hypoxia, vascular endothelial growth factor (VEGF) is secreted. For appropriate VEGF-induced vessel growth, sufficient levels of insulin-like growth factor I (IGF-I) in serum are necessary. IGF-I is a peptide, related to nutrition supply, which is essential for both pre- and post-natal general growth as well as for growth of the retinal vasculature. In prematurely born infants, serum levels are closely related to gestational age and are lower in more prematurely born infants. At preterm birth the placental supply of nutrients is lost, growth factors are suddenly reduced and general as well as vascular growth slows down or ceases. In addition, the relative hyperoxia of the extra-uterine milieu, together with supplemental oxygen, causes a regression of already developed retinal vessels. Postnatal growth retardation is a major problem in very preterm infants. Both poor early weight gain and low serum levels of IGF-I during the first weeks/months of life have been found to be correlated with severity of ROP. Conclusion: This review will focus on the mechanisms leading to ROP by exploring factors responsible for poor early weight gain and abnormal vascularisation of the eye of the preterm infant. [source] Growth defect in Grg5 null mice is associated with reduced Ihh signaling in growth platesDEVELOPMENTAL DYNAMICS, Issue 1 2002Wen-Fang Wang Abstract Gene-targeted disruption of Grg5, a mouse homologue of Drosophila groucho (gro), results in postnatal growth retardation in mice. The growth defect, most striking in approximately half of the Grg5 null mice, occurs during the first 4,5 weeks of age, but most mice recover retarded growth later. We used the nonlinear mixed-effects model to fit the growth data of wild-type, heterozygous, and Grg5 null mice. On the basis of preliminary evidence suggesting an interaction between Grg5 and the transcription factor Cbfa1/Runx2, critical for skeletal development, we further investigated the skeleton in the mice. A long bone growth plate defect was identified, which included shorter zones of proliferative and hypertrophic chondrocytes and decreased trabecular bone formation. This decreased trabecular bone formation is likely caused by a reduced recruitment of osteoblasts into the growth plate region of Grg5 null mice. Like the growth defect, the growth plate and trabecular bone abnormality improved as the mice grew older. The growth plate defect was associated with reduced Indian hedgehog expression and signaling. We suggest that Grg5, a transcriptional coregulator, modulates the activities of transcription factors, such as Cbfa1/Runx2 in vivo to affect Ihh expression and the function of long bone growth plates. © 2002 Wiley-Liss, Inc. [source] OBSL1 mutations in 3-M syndrome are associated with a modulation of IGFBP2 and IGFBP5 expression levels,HUMAN MUTATION, Issue 1 2010Celine Huber Abstract 3-M syndrome is an autosomal recessive disorder characterized by severe pre- and postnatal growth retardation and minor skeletal changes. We have previously identified CUL7 as a disease-causing gene but we have also provided evidence of genetic heterogeneity in the 3-M syndrome. By homozygosity mapping in two inbred families, we found a second disease locus on chromosome 2q35,36.1 in a 5.2-Mb interval that encompasses 60 genes. To select candidate genes, we performed microarray analysis of cultured skin fibroblast RNA from one patient, looking for genes with altered expression; we found decreased expression of IGFBP2 and increased expression of IGFBP5. However, direct sequencing of these two genes failed to detect any anomaly. We then considered other candidate genes by their function/location and found nine distinct mutations in the OBSL1 gene in 13 families including eight nonsense and one missense mutations. To further understand the links between OBSL1, CUL7, and insulin-like growth factor binding proteins (IGFBPs), we performed real-time quantitative PCR (RT-PCR) analysis for OBSL1, CUL7, IGFBP2, and IGFBP5, using cultured fibroblast RNAs from two patients with distinct OBSL1 mutations (p.F697G; p.H814RfsX15). We found normal CUL7 mRNA levels but abnormal IGFBP2 and IGFBP5 mRNA levels in the two patients, suggesting that OBSL1 modulates the expression of IGFBP proteins. Hum Mutat 30:1,7, 2009. © 2009 Wiley-Liss, Inc. [source] Clinical features of maternal uniparental disomy 14 in patients with an epimutation and a deletion of the imprinted DLK1/GTL2 gene cluster,,HUMAN MUTATION, Issue 9 2008Karin Buiting Abstract Maternal uniparental disomy 14 [upd(14)mat] is associated with a recognizable phenotype that includes pre- and postnatal growth retardation, neonatal hypotonia, feeding problems and precocious puberty. Chromosome 14 contains an imprinted gene cluster, which is regulated by a differentially methylated region (IG-DMR) between DLK1 and GTL2. Here we report on four patients with clinical features of upd(14)mat who show a maternal-only methylation pattern, but biparental inheritance for chromosome 14. In three of the patients loss of paternal methylation appears to be a primary epimutation, whereas the other patient has a paternally derived deletion of ,1,Mb that includes the imprinted DLK1-GTL2 gene cluster. These findings demonstrate that the upd(14)mat phenotype is caused by altered expression of genes within this cluster. Hum Mutat 0, 1,6, 2008. © 2008 Wiley-Liss, Inc. [source] Seckel syndrome associated with oligodontia, microdontia, enamel hypoplasia, delayed eruption, and dentin dysmineralization: a new variant?JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2006P. J. De Coster Seckel syndrome (SCKL) [OMIM Entry 210600] is a rare, autosomal recessive syndrome, characterized by severe intrauterine and postnatal growth retardation, microcephaly, mental retardation, and typical facial appearance with beaklike protrusion of the midface (bird-headed). Associated findings may include limb anomalies, dislocation of femoral heads, scoliosis, and gastrointestinal malformation. A 14-year-old boy is presented with brain hypoplasia, pachygyria, hydrocephaly, enamel hypoplasia and root dysplasia in the temporary dentition, and oligodontia, severe microdontia, and delayed eruption of the permanent dentition. The association of SCKL with the above unusual dental findings may represent a new phenotype. [source] | |||||||||||||