Mutations in the latent TGF-beta binding protein 3 (LTBP3) gene cause brachyolmia with amelogenesis imperfecta

Inherited dental malformations constitute a clinically and genetically heterogeneous group of disorders. Here, we report on four families, three of them consanguineous, with an identical phenotype, characterized by significant short stature with brachyolmia and hypoplastic amelogenesis imperfecta (AI) with almost absent enamel. This phenotype was first described in 1996 by Verloes et al. as an autosomal recessive form of brachyolmia associated with AI. Whole-exome sequencing resulted in the identification of recessive hypomorphic mutations including deletion, nonsense and splice mutations, in the LTBP3 gene, which is involved in the TGF-beta signaling pathway. We further investigated gene expression during mouse development and tooth formation. Differentiated ameloblasts synthesizing enamel matrix proteins and odontoblasts expressed the gene. Study of an available knockout mouse model showed that the mutant mice displayed very thin to absent enamel in both incisors and molars, hereby recapitulating the AI phenotype in the human disorder

Safety and effects of two red blood cell transfusion strategies in pediatric cardiac surgery patients: a randomized controlled trial

To investigate the safety and effects of a restrictive red blood cell (RBC) transfusion strategy in pediatric cardiac surgery patients. Randomized controlled trial. Pediatric ICU in an academic tertiary care center, Leiden University Medical Center, Leiden, The Netherlands. One hundred seven patients with non-cyanotic congenital heart defects between 6 weeks and 6 years of age. One hundred three patients underwent corrective surgery on cardiopulmonary bypass. Prior to surgery patients were randomly assigned to one of two groups with specific RBC transfusion thresholds: Hb 10.8 g/dl (6.8 mmol/l) and Hb 8.0 g/dl (5.0 mmol/l). Length of stay in hospital (primary outcome), length of stay in PICU, duration of ventilation (secondary outcome), incidence of adverse events and complications related to randomization (intention to treat analysis). In the restrictive transfusion group, mean volume of transfused RBC was 186 (±70) ml per patient and in the liberal transfusion group 258 (±87) ml per patient, (95% CI 40.6-104.6), p < 0.001. Length of hospital stay was shorter in patients with a restrictive RBC transfusion strategy: median 8 (IQR 7-11) vs. 9 (IQR 7-14) days, p = 0.047. All other outcome measures and incidence of adverse effects were equal in both RBC transfusion groups. Cost of blood products for the liberal transfusion group was 438.35 (±203.39) vs. 316.27 (±189.96) euros (95% CI 46.61-197.51) per patient in the restrictive transfusion group, p = 0.002. For patients with a non-cyanotic congenital heart defect undergoing elective cardiac surgery, a restrictive RBC transfusion policy (threshold of Hb 8.0 g/dl) during the entire perioperative period is safe, leads to a shorter hospital stay and is less expensiv