40 research outputs found
Heterozygous De Novo Truncating Mutation of Nucleolin in an ASD Individual Disrupts Its Nucleolar Localization
Nucleolin (NCL/C23; OMIM: 164035) is a major nucleolar protein that plays a critical role in multiple processes, including ribosome assembly and maturation, chromatin decondensation, and pre-rRNA transcription. Due to its diverse functions, nucleolin has frequently been implicated in pathological processes, including cancer and viral infection. We recently identified a de novo frameshifting indel mutation of NCL, p.Gly664Glufs*70, through whole-exome sequencing of autism spectrum disorder trios. Through the transfection of constructs encoding either a wild-type human nucleolin or a mutant nucleolin with the same C-terminal sequence predicted for the autism proband, and by using co-localization with the nucleophosmin (NPM; B23) protein, we have shown that the nucleolin mutation leads to mislocalization of the NCL protein from the nucleolus to the nucleoplasm. Moreover, a construct with a nonsense mutation at the same residue, p.Gly664*, shows a very similar effect on the location of the NCL protein, thus confirming the presence of a predicted nucleolar location signal in this region of the NCL protein. Real-time fluorescence recovery experiments show significant changes in the kinetics and mobility of mutant NCL protein in the nucleoplasm of HEK293Tcells. Several other studies also report de novo NCL mutations in ASD or neurodevelopmental disorders. The altered mislocalization and dynamics of mutant NCL (p.G664Glufs*70/p.G664*) may have relevance to the etiopathlogy of NCL-related ASD and other neurodevelopmental phenotypes
VaRank: a simple and powerful tool for ranking genetic variants:
Background. Most genetic disorders are caused by single nucleotide variations (SNVs) or small insertion/deletions (indels). High throughput sequencing has broadened the catalogue of human variation, including common polymorphisms, rare variations or disease causing mutations. However, identifying one variation among hundreds or thousands of others is still a complex task for biologists, geneticists and clinicians. Results. We have developed VaRank, a command-line tool for the ranking of genetic variants detected by high-throughput sequencing. VaRank scores and prioritizes variants annotated either by Alamut Batch or SnpEff. A barcode allows users to quickly view the presence/absence of variants (with homozygote/heterozygote status) in analyzed samples. VaRank supports the commonly used VCF input format for variants analysis thus allowing it to be easily integrated into NGS bioinformatics analysis pipelines. VaRank has been successfully applied to disease-gene identification as well as to molecular diagnostics setup for several hundred patients. Conclusions. VaRank is implemented in Tcl/Tk, a scripting language which is platform-independent but has been tested only on Unix environment. The source code is available under the GNU GPL, and together with sample data and detailed documentation can be downloaded from http://www.lbgi.fr/VaRank/
An integrated diagnosis strategy for congenital myopathies
Congenital myopathies are severe muscle disorders affecting adults as well as children in all populations. The diagnosis of congenital myopathies is constrained by strong clinical and genetic heterogeneity. Moreover, the majority of patients present with unspecific histological features, precluding purposive molecular diagnosis and demonstrating the need for an alternative and more efficient diagnostic approach. We used exome sequencing complemented by histological and ultrastructural analysis of muscle biopsies to identify the causative mutations in eight patients with clinically different skeletal muscle pathologies, ranging from a fatal neonatal myopathy to a mild and slowly progressive myopathy with adult onset. We identified RYR1 (ryanodine receptor) mutations in six patients and NEB (nebulin) mutations in two patients. We found novel missense and nonsense mutations, unraveled small insertions/deletions and confirmed their impact on splicing and mRNA/protein stability. Histological and ultrastructural findings of the muscle biopsies of the patients validated the exome sequencing results. We provide the evidence that an integrated strategy combining exome sequencing with clinical and histopathological investigations overcomes the limitations of the individual approaches to allow a fast and efficient diagnosis, accelerating the patient's access to a better healthcare and disease management. This is of particular interest for the diagnosis of congenital myopathies, which involve very large genes like RYR1 and NEB as well as genetic and phenotypic heterogeneity
To retain or remove the syndesmotic screw: a review of literature
Introduction: Syndesmotic positioning screws are frequently placed in unstable ankle fractures. Many facets of adequate placement techniques have been the subject of various studies. Whether or not the syndesmosis screw should be removed prior to weight-bearing is still debated. In this study, the recent literature is reviewed concerning the need for removal of the syndesmotic screw. Materials and methods: A comprehensive literature search was conducted in the electronic databases of the Cochrane Library, Pubmed Medline and EMbase from January 2000 to October 2010. Results: A total of seven studies were identified in the literature. Most studies found no difference in outcome between retained or removed screws. Patients with screws that were broken, or showed loosening, had similar or improved outcome compared to patients with removed screws. Removal of the syndesmotic screws, when deemed necessary, is usually not performed before 8-12 weeks. Conclusion: There is paucity in randomized controlled trials on the absolute need for removal of the syndesmotic screw. However, current literature suggests that it might be reserved for intact screws that cause hardware irritation or reduced range of motion after 4-6 months
Unusual multisystemic involvement and a novel BAG3 mutation revealed by NGS screening in a large cohort of myofibrillar myopathies
Background: Myofibrillar myopathies (MFM) are a group of phenotypically and genetically heterogeneous neuromuscular disorders, which are characterized by protein aggregations in muscle fibres and can be associated with multisystemic involvement. Methods: We screened a large cohort of 38 index patients with MFM for mutations in the nine thus far known causative genes using Sanger and next generation sequencing (NGS). We studied the clinical and histopathological characteristics in 38 index patients and five additional relatives (n = 43) and particularly focused on the associated multisystemic symptoms. Results: We identified 14 heterozygous mutations (diagnostic yield of 37%), among them the novel p.Pro209Gln mutation in the BAG3 gene, which was associated with onset in adulthood, a mild phenotype and an axonal sensorimotor polyneuropathy, in the absence of giant axons at the nerve biopsy. We revealed several novel clinical phenotypes and unusual multisystemic presentations with previously described mutations: hearing impairment with a FLNC mutation, dysphonia with a mutation in DES and the first patient with a FLNC mutation presenting respiratory insufficiency as the initial symptom. Moreover, we described for the first time respiratory insufficiency occurring in a patient with the p.Gly154Ser mutation in CRYAB. Interestingly, we detected a polyneuropathy in 28% of the MFM patients, including a BAG3 and a MYOT case, and hearing impairment in 13%, including one patient with a FLNC mutation and two with mutations in the DES gene. In four index patients with a mutation in one of the MFM genes, typical histological findings were only identified at the ultrastructural level (29%). Conclusions: We conclude that extraskeletal symptoms frequently occur in MFM, particularly cardiac and respiratory involvement, polyneuropathy and/or deafness. BAG3 mutations should be considered even in cases with a mild phenotype or an adult onset. We identified a genetic defect in one of the known genes in less than half of the MFM patients, indicating that more causative genes are still to be found. Next generation sequencing techniques should be helpful in achieving this aim
Dominance of paternalism in family-centered care in the pediatric intensive care unit (PICU): An ethnographic study
This article examines the culture of family-centered care (FCC) in the pediatric intensive care unit (PICU) using focused ethnography. Data collection strategy was participant observation, fieldwork, and interviews with main actors of the PICU, namely supervisors, nurses, and parents. This study took place in one PICU in a hospital in Tehran, Iran. The results were in the main named as paternalism and were presented as five themes: "non-possessed environment," "separation of the children from their parents," non-interactive communication," "limited participation," and "affection and sympathy combined with superiority." In conclusion, the prevailing atmosphere in care was paternalistic as there was a huge gap between conceptually or theoretically accepted application of FCC in PICU and what is practically administrated. Bridging such a gap between theory and practice can be helpful in improving social, environment, and organizational culture for the children, their parents, and health care providers as well as their performance in the context of PICU. © 2015 Informa Healthcare USA, Inc. All rights reserved: reproduction in whole or part not permitted
The Views of Parents of Premature Babies Hospitalized in Neonatal Intensive Care Unit about the Implementation of Family-Centered Care in This Unit
Background and Objective: Family-centered care is a new healthcare standard that allows parents to be involved in their baby's healthcare. Considering that parents play an important role in caring for the baby in the hospital as well as at home after discharge, family-oriented care is always emphasized. Therefore, the aim of this study is to investigate the viewpoint of parents of newborns hospitalized in neonatal special care unit about the implementation of family-oriented care in this unit.
Methods: This cross-sectional study was conducted on 100 mothers and fathers of newborns hospitalized in the neonatal intensive care unit of selected hospitals of Shahid Beheshti University of Medical Sciences in Tehran. After obtaining informed consent, the researcher completed the questionnaires in a period of three months by explaining the objectives of the research as well as family-oriented care in groups and individually. The demographic information of the parents and the newborn was collected and analyzed using a researcher-made questionnaire to examine the views of the parents in different areas about the implementation of family-centered care in the neonatal special care unit.
Findings: The mean score of the questionnaires for the mothers of babies was 172.7±19.8 and the mean score of the questionnaires for the fathers was 152.5±30.9. In the area of education and information provision, the mean score of mothers was 49±3.5 and the mean score of fathers was 42.6±3.5; mothers score was significantly higher than that of fathers (p<0.001). In the area of respect for parents' rights, the mean score of fathers was 16.7±1.6 and the mean score of mothers was 11.3±5.8; in this area, the mean score of fathers was significantly higher than the score of mothers (p<0.001). In other areas, there was no statistically significant difference between the views of fathers and mothers.
Conclusion: The view of fathers and mothers in the field of family-centered care in special care units for newborns has been positive and satisfactory. This shows the necessity of different programs in order to improve the views of fathers and mothers
Eur J Hum Genet
Mutations impacting on the splicing of pre-mRNA are one important cause of genetically inherited diseases. However, detection of splice mutations, that are mainly due to intronic variations, and characterization of their effects are usually not performed as a first approach during genetic diagnosis. X-linked recessive myotubular myopathy is a severe congenital myopathy due to mutations in the MTM1 gene encoding myotubularin. Here, we screened a male patient showing an unusually mild phenotype without respiratory distress by western blot with specific myotubularin antibodies and detected a strong reduction of the protein level.The disease was subsequently linked to a hemizygous point mutation affecting the acceptor splice site of exon 8 of MTM1, proven by protein, transcript and genomic DNA analysis. Detailed analysis of the MTM1 mRNA by RT-PCR, sequencing and quantitative PCR revealed multiple abnormal transcripts with retention of a truncated exon 8, and neighboring exons 7 and 9 but exclusion of several other exons, suggesting a complex effect of this mutation on the splicing of non-adjacent exons. We conclude that the analysis of RNA by RT-PCR and sequencing is an important step to characterize the precise impact of detected splice variants. It is likely that complex splice aberrations due to a single mutation also account for unsolved cases in other diseases