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Behlouli A.,University of Science and Technology Houari Boumediene | Behlouli A.,University Alger 1 | Bonnet C.,French Institute of Health and Medical Research | Abdi S.,University Alger 1 | And 11 more authors.
International Journal of Pediatric Otorhinolaryngology | Year: 2016

Congenital deafness is certainly one of the most common monogenic diseases in humans, but it is also one of the most genetically heterogeneous, which makes molecular diagnosis challenging in most cases. Whole-exome sequencing in two out of three Algerian siblings affected by recessively-inherited, moderate to severe sensorineural deafness allowed us to identify a novel splice donor site mutation (c.5272. +. 1G > A) in the gene encoding α-tectorin, a major component of the cochlear tectorial membrane. The mutation was present at the homozygous state in the three affected siblings, and at the heterozygous state in their unaffected, consanguineous parents. To our knowledge, this is the first reported TECTA mutation leading to the DFNB21 form of hearing impairment among Maghrebian individuals suffering from congenital hearing impairment, which further illustrates the diversity of the genes involved in congenital deafness in the Maghreb. © 2016 Elsevier Ireland Ltd. Source


Schaefer E.,Hopitaux Universitaires Of Strasbourg | Schaefer E.,University of Strasbourg | Collet C.,Service de Biochimie et de Biologie Moleculaire | Genevieve D.,Montpellier University | And 11 more authors.
Genetics in Medicine | Year: 2014

Purpose:Treacher Collins syndrome is a mandibulofacial dysostosis caused by mutations in genes involved in ribosome biogenesis and synthesis. TCOF1 mutations are observed in ∼80% of the patients and are inherited in an autosomal dominant manner. Recently, two other genes have been reported in <2% of patients - POLR1D in patients with autosomal dominant inheritance, and POLR1C in patients with autosomal recessive inheritance.Methods:We performed direct sequencing of TCOF1, POLR1C, and POLR1D in two unrelated consanguineous families.Results:The four affected children shared the same homozygous mutation in POLR1D (c.163C>G, p.Leu55Val). This mutation is localized in a region encoding the dimerization domain of the RNA polymerase. It is supposed that this mutation impairs RNA polymerase, resulting in a lower amount of mature dimeric ribosomes. A functional analysis of the transcripts of TCOF1 by real-time quantitative reverse transcription-polymerase chain reaction was performed in the first family, demonstrating a 50% reduction in the index case, compatible with this hypothesis.Conclusion:This is the first report of POLR1D mutation being responsible for an autosomal recessive inherited Treacher Collins syndrome. These results reinforce the concept of genetic heterogeneity of Treacher Collins syndrome and underline the importance of combining clinical expertise and familial molecular analyses for appropriate genetic counseling.Genet Med 16 9, 720-724. © American College of Medical Genetics and Genomics. Source


Riche F.,Hopital Lariboisiere | Gayat E.,Hopital Lariboisiere | Gayat E.,French Institute of Health and Medical Research | Gayat E.,University Paris Diderot | And 12 more authors.
Critical Care | Year: 2013

Introduction: Our aim was to describe inflammatory cytokines response in the peritoneum and plasma of patients with peritonitis. We also tested the hypothesis that scenarios associated with worse outcome would result in different cytokine release patterns. Therefore, we compared cytokine responses according to the occurrence of septic shock, mortality, type of peritonitis and peritoneal microbiology. Methods: Peritoneal and plasma cytokines (interleukin (IL) 1, tumor necrosis factor α (TNFα), IL-6, IL-10, and interferon γ (IFNγ)) were measured in 66 patients with secondary peritonitis. Results: The concentration ratio between peritoneal fluid and plasma cytokines varied from 5 (2 to 21) (IFNγ) to 1310 (145 to 3888) (IL-1). There was no correlation between plasma and peritoneal fluid concentration of any cytokine. In the plasma, TNFα, IL-6, IFNγ and IL-10 were higher in patients with shock versus no shock and in nonsurvivors versus survivors (P ≤0.03). There was no differential plasma release for any cytokine between community-acquired and postoperative peritonitis. The presence of anaerobes or Enterococcus species in peritoneal fluid was associated with higher plasma TNFα: 50 (37 to 106) versus 38 (29 to 66) and 45 (36 to 87) versus 39 (27 to 67) pg/ml, respectively (P = 0.02). In the peritoneal compartment, occurrence of shock did not result in any difference in peritoneal cytokines. Peritoneal IL-10 was higher in patients who survived (1505 (450 to 3130) versus 102 (9 to 710) pg/ml; P = 0.04). The presence of anaerobes and Enterococcus species was associated with higher peritoneal IFNγ: 2 (1 to 6) versus 10 (5 to 28) and 7 (2 to 39) versus 2 (1 to 6), P = 0.01 and 0.05, respectively). Conclusions: Peritonitis triggers an acute systemic and peritoneal innate immune response with a simultaneous release of pro and anti-inflammatory cytokines. Higher levels of all cytokines were observed in the plasma of patients with the most severe conditions (shock, non-survivors), but this difference was not reflected in their peritoneal fluid. There was always a large gradient in cytokine concentration between peritoneal and plasma compartments highlighting the importance of compartmentalization of innate immune response in peritonitis. © 2013 Riché et al.; licensee BioMed Central Ltd. Source


Schiltz C.,French Institute of Health and Medical Research | Schiltz C.,University Paris Diderot | Prouillet C.,French Institute of Health and Medical Research | Prouillet C.,University Paris Diderot | And 9 more authors.
Journal of Cellular Physiology | Year: 2010

The Runx2 gene is essential for osteoblast differentiation and function. In vivo over-expression of Runx2 in osteoblasts increases bone resorption, and blocks terminal osteoblast differentiation. Several lines of evidence suggest that osteoblastic matrix metalloproteinases (MMPs) could contribute to the increased bone resorption observed in mice over-expressing Runx2 (Runx2 mice). The goal of our study was to use a transgenic approach to find out whether the inhibition of osteoblastic MMPs can reduce the bone loss induced by the over-expression of Runx2. We analyzed the effect of the in vivo over-expression of the TIMP-1 in osteoblasts on the severe osteopenic phenotype in Runx2 mice. Females with the different genotypes (WT, Runx2, TIMP-1 and TIMP-1/Runx2) were analyzed for bone density, architecture, osteoblastic and osteoclastic activity and gene expression using qPCR. TIMP-1 over-expression reduces the bone loss in adult Runx2 mice. The prevention of the bone loss in TIMP-1/Runx2 mice was due to a combination of reduced bone resorption and sustained bone formation. We present evidence that the ability of osteoblastic cells to induce osteoclastic differentiation is lower in TIMP-1/Runx2 mice than in Runx2 mice, probably due to a reduction in the expression of RANK-L and of the Runx2 transgene. Osteoblast primary cells from TIMP-1/Runx2 mice, but not from Runx2 mice, were able to differentiate into fully mature osteoblasts producing high osteocalcin levels. In conclusion, our findings suggest that osteoblastic MMPs can affect osteoblast differentiation. Our work also indicates that osteoblastic MMPs are partly responsible for the bone loss observed in Runx2 transgenic mice. © 2009 Wiley-Liss, Inc. Source


Guillot L.,French Institute of Health and Medical Research | Carre A.,University of Paris Descartes | Szinnai G.,University of Basel | Castanet M.,University of Paris Descartes | And 10 more authors.
Human Mutation | Year: 2010

NKX2-1 (NK2 homeobox 1) is a critical regulator of transcription for the surfactant protein (SP)-B and -C genes (SFTPB and SFTPC, respectively). We identified and functionally characterized two new de novo NKX2-1 mutations c.493C>T (p.R165W) and c.786-787del2 (p.L263fs) in infants with closely similar severe interstitial lung disease (ILD), hypotonia, and congenital hypothyroidism. Functional analyses using A549 and HeLa cells revealed that NKX2-1-p.L263fs induced neither SFTPB nor SFTPC promoter activation and had a dominant negative effect on wild-type (WT) NKX2-1. In contrast, NKX2-1-p.R165W activated SFTPC, to a significantly greater extent than did WT NKX2-1, while SFTPB activation was only significantly reduced in HeLa cells. In accordance with our in vitro data, we found decreased amounts of SP-B and SP-C by western blot in bronchoalveolar lavage fluid (patient with p.L263fs) and features of altered surfactant protein metabolism on lung histology (patient with NKX2-1-p.R165W). In conclusion, ILD in patients with NKX2-1 mutations was associated with altered surfactant protein metabolism, and both gain and loss of function of the mutated NKX2-1 genes on surfactant protein promoters were associated with ILD in "Brain-Lung-Thyroid syndrome". © 2009 Wiley-Liss, Inc. Source

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