346 research outputs found

    Defect in proline synthesis: pyrroline-5-carboxylate reductase 1 deficiency leads to a complex clinical phenotype with collagen and elastin abnormalities

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    Pyrroline-5-carboxylate reductase 1 (PYCR1) catalyzes the last step in proline synthesis. Deficiency of PYCR1, caused by a defect in PYCR1, was recently described in patients with cutis laxa, intrauterine growth retardation, developmental dysplasia of the hips and mental retardation. In this paper, we describe additional six patients (ages ranging from 4 months to 55 years) from four Iranian families with clinical manifestations of a wrinkly skin disorder. All patients have distinct facial features comprising triangular face, loss of adipose tissue and thin pointed nose. Additional features are short stature, wrinkling over dorsum of hand and feet, visible veins over the chest and hyperextensible joints. Three of the patients from a large consanguineous family do not have mental retardation, while the remaining three patients from three unrelated families have mental and developmental delay. Mutation analysis revealed the presence of disease-causing variants in PYCR1, including a novel deletion of the entire PYCR1 gene in one family, and in each of the other patients the homozygous missense mutations c.616G > A (p.Gly206Arg), c.89T > A (p.Ile30Lys) and c.572G > A (p.Gly191Glu) respectively, the latter two of which are novel. Light- and electron microscopy investigations of skin biopsies showed smaller and fragmented elastic fibres, abnormal morphology of the mitochondria and their cristae, and slightly abnormal collagen fibril diameters with irregular outline and variable size. In conclusion, this study adds information on the natural course of PYCR1 deficiency and sheds light on the pathophysiology of this disorder. However, the exact pathogenesis of this new disorder and the role of proline in the development of the clinical phenotype remain to be fully explaine

    Ullrich Congenital Muscular Dystrophy (UCMD): Clinical and Genetic Correlations

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    How to Cite This Article: Bozorgmehr B, Kariminejad A, Nafissi Sh, Jebelli B, Andoni U, Gartioux C, Ledeuil C, Allamand Y, Richard P, Kariminejad MH. Ullrich Congenital Muscular Dystrophy (UCMD):Clinical and Genetic Correlations. Iran J Child Neurol. 2013 Summer; 7(3): 15-22.  Objective:Ullrich congenital muscular dystrophy (UCMD) corresponds to the severe end of the clinical spectrum of neuromuscular disorders caused by mutations in the genes encoding collagen VI (COL VI). We studied four unrelated families with six affected children that had typical UCMD with dominant and recessive inheritance.Materials & MethodsFour unrelated Iranian families with six affected children with typical UCMD were analyzed for COLVI secretion in skin fibroblast culture and the secretion of COLVI in skin fibroblast culture using quantitative RT–PCR (Q-RT-PCR), and mutation identification was performed by sequencing of complementary DNA.ResultsCOL VI secretion was altered in all studied fibroblast cultures. Two affected sibs carried a homozygous nonsense mutation in exon 12 of COL6A2, while another patient had a large heterozygous deletion in exon 5-8 of COL6A2. The two other affected sibs had homozygote mutation in exon 24 of COL6A2, and the last one was homozygote in COL6A1.ConclusionIn this study, we found out variability in clinical findings and genetic inheritance among UCMD patients, so that the patient with complete absence of COLVI was severely affected and had a large heterozygous deletion in COL6A2. In contrast, the patients with homozygous deletion had mild to moderate decrease in the secretion of COL VI and were mildly tomoderately affected.References1. Voit T. Congenital Muscular Dystrophies Brain Dev 1998;20(2): 65-74.2. Ullrich OZ Ges. Scleroatonic Muscular Dystrophy. NeurolPsychiatr 1930;126:171-201.3. Ullrich O. Monatsschr. Kinderheilkd 1930;47:502-10.4. Mercuri E, Yuva Y, Brown SC, Brockington M, Kinali M, Jungbluth H, et al. Collagen VI involvement in Ullrich Syndrome: A Clinical, genetic and Immunohistochemical study. Neurology 2002;58(9):1354-9.5. Lampe AK, Bushby KM. Collagen VI related muscle disorders. J Med Genet 2005;42(9):673-85.6. Mercuri E, Muntoni F. Congenital Muscular Dystrophies. In: Emery AEH, editors. The muscular dystrophies. Oxford: Oxford University Press: 2001. p. 10-38.7. Furukawa T, Toyokura Y. Congenital Hypotonic-Sclerotic muscular dystrophy. J Med Genet 1977;14(6):426-9.8. Nonaka I, Une Y, Ishihara T, Miyoshino S, Nakashima T, Sugita H. A clinical and histological study of Ullrich’s disease (congenital atonic-sclerotic muscular dystrophy). Neuropediatrics 1981; 12(3):197-208.9. Pan TC, Zhang RZ, Sudano DG, Marie SK, Bonnemann CG, Chu ML. New molecular mechanism for Ullrich Congenital Muscular Dystrophy: A heterozygous inframe deletion in the COL6A1 gene causes a severe phenotype. Am J Hum Genet 2003;73(2):355-69.10. Baker NL, Morgelin M, Peat R, Goemans N, North KN, Baterman JF, et al. Dominant Collagen VI Mutations are acommon cause of ullrich congenital muscular dystrophy. Hum Mol Genet 2005;14(2]):279-93.11. Pace RA, Peat RA, Baker NL, Zamurs L, Morgelin M, Irving M et al. Collagen VI glycine mutations: Perturbed assembly and a spectrum of clinical severity. Ann Neurol 2008;64(3):294-303.12. Bethlem J, Wijngaarden GK. Benign myopathy, with autosomal dominant inheritance. A report on three pedigress. Brain 1976;99(1):91-100.13. Gualandi F, Urciuolo A, Martoni E, Sabatelli P, Squarzoni S, Bovolenta M, et al Auotosomal recessive Bethlem myopath. Neurology 2009;73(22):1883-91.14. Foley AR, Hu Y, Zou Y, Columbus A, Shoffiner J, Dunn DM, et al. Autosomal recessive Bethlam Myopathy. Neuromuscular Disord 2009;19(10):813-7.

    Detection of new translocation in infant twins with concordant ALL and discordant outcome

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    About 2-5 of acute lymphoblastic leukemia (ALL) cases in pediatric patients are infants with an unfavorable prognosis because of high relapse probability. Early detection of the disease is, therefore, very important. Despite the fact that leukemia in twins occurs rarely, more attention has been paid to it in genetic studies. In the present study, through cytogenetic testing, a special case of concordant ALL in monozygotic twins was presented with different outcomes. In spite of an acceptable initial consequence to medical treatment in twins, in another brother (Twin B), early relapse was observed. In the cytogenetic study, both twins expressed t (4; 11) (q21; q23) while twin A expressed t (2; 7) (p10; q10). No cases have previously reported this mutation. Whether this translocation has a protective role for leukemia with mixed-lineage leukemia (MLL) gene rearrangement is still unclear. The difference in the translocation identified in the identical twins is also subject to further investigations. © 2020 by the authors

    Recessive mutation in tetraspanin CD151 causes Kindler syndrome-like epidermolysis bullosa with multi-systemic manifestations including nephropathy

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    Epidermolysis bullosa (EB) is caused by mutations in as many as 19 distinct genes. We have developed a next-generation sequencing (NGS) panel targeting genes known to be mutated in skin fragility disorders, including tetraspanin CD151 expressed in keratinocytes at the dermal-epidermal junction. The NGS panel was applied to a cohort of 92 consanguineous families of unknown subtype of EB. In one family, a homozygous donor splice site mutation in CD151 (NM_139029; c.351 + 2T > C) at the exon 5/intron 5 border was identified, and RT-PCR and whole transcriptome analysis by RNA-seq confirmed deletion of the entire exon 5 encoding 25 amino acids. Immunofluorescence of proband's skin and Western blot of skin proteins with a monoclonal antibody revealed complete absence of CD151. Transmission electron microscopy showed intracellular disruption and cell-cell dysadhesion of keratinocytes in the lower epidermis. Clinical examination of the 33-year old proband, initially diagnosed as Kindler syndrome, revealed widespread blistering, particularly on pretibial areas, poikiloderma, nail dystrophy, loss of teeth, early onset alopecia, and esophageal webbing and strictures. The patient also had history of nephropathy with proteinuria. Collectively, the results suggest that biallelic loss-of-function mutations in CD151 underlie an autosomal recessive mechano-bullous disease with systemic features. Thus, CD151 should be considered as the 20th causative, EB-associated gene

    Alx4 relays sequential FGF signaling to induce lacrimal gland morphogenesis

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    The sequential use of signaling pathways is essential for the guidance of pluripotent progenitors into diverse cell fates. Here, we show that Shp2 exclusively mediates FGF but not PDGF signaling in the neural crest to control lacrimal gland development. In addition to preventing p53-independent apoptosis and promoting the migration of Sox10-expressing neural crests, Shp2 is also required for expression of the homeodomain transcription factor Alx4, which directly controls Fgf10 expression in the periocular mesenchyme that is necessary for lacrimal gland induction. We show that Alx4 binds an Fgf10 intronic element conserved in terrestrial but not aquatic animals, underlying the evolutionary emergence of the lacrimal gland system in response to an airy environment. Inactivation of ALX4/Alx4 causes lacrimal gland aplasia in both human and mouse. These results reveal a key role of Alx4 in mediating FGF-Shp2-FGF signaling in the neural crest for lacrimal gland development., The dry eye disease caused by lacrimal gland dysgenesis is one of the most common ocular ailments. In this study, we show that Shp2 mediates the sequential use of FGF signaling in lacrimal gland development. Our study identifies Alx4 as a novel target of Shp2 signaling and a causal gene for lacrimal gland aplasia in humans. Given this result, there may also be a potential role for Alx4 in guiding pluripotent stem cells to produce lacrimal gland tissue. Finally, our data reveals an Alx4-Fgf10 regulatory unit broadly conserved in the diverse array of terrestrial animals from humans to reptiles, but not in aquatic animals such as amphibians and fish, which sheds light on how the lacrimal gland arose as an evolutionary innovation of terrestrial animals to adapt to their newfound exposure to an airy environment

    A Comparison of the Viewpoints of Clinical Educators and Students of the University of Social Welfare and Rehabilitation Sciences toward Clinical Training Status of Rehabilitation Disciplines in 2013-14

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    Background & Objective: Clinical education courses are recognized as the heart of professional education because more than 50% of students’ time is spent in clinical environments. Therefore, qualifying in clinical skills requires an effective clinical learning environment. Thus, clinical education can be enriched through the consideration of clinical educators’ and students’ perspectives . The aim of this study was to compare the viewpoints of clinical educators and students of the University of Social Welfare and Rehabilitation Sciences, Tehran, Iran, toward the clinical education status of rehabilitation disciplines. Methods: This study was a cross-sectional study. Based on the inclusion criteria and using convenience sampling method, 54 clinical educators and 178 students were chosen from among clinical educators and students of orthopedics, physiotherapy, occupational therapy, and speech therapy disciplines. The participants completed valid and reliable clinical education questionnaires in the field of rehabilitation. Results: A statistical difference was observed between clinical educators’ and students’ viewpoints in the area of “clinical learners”. With regard to the academic degrees of clinical educators, there was a statistically significant difference in the “evaluation area”. With regard to the gender of clinical educators, differences were observed in the area of “clinical learners”. According to students’ academic disciplines, with the exception of the field of “management”, statistical differences were observed in other areas. Conclusion: Clinical education courses in Rehabilitation Sciences must provide an effective clinical learning setting. Moreover, reviewing of management and evaluation of clinical education through appropriate evaluation criteria in order to improve the clinical education status is necessary. Key Words: Rehabilitation, Clinical education, Clinical instructor, Studen

    Ultrasound sensors for process monitoring in injection moulding

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    Injection moulding is an extremely important industrial process, being one of the most commonly-used plastic formation techniques. However, the industry faces many current challenges associated with demands for greater product customisation, higher precision and most urgently a shift towards more sustainable materials and processing. Accurate real-time sensing of the material and part properties during processing is key to achieving rapid process optimisation and set-up, reducing downtimes, and reducing waste material and energy in the production of defective products. While most commercial processes rely on point measurements of pressure and temperature, ultrasound transducers represent a non-invasive and non-destructive source of rich information on the mould, the cavity, and the polymer melt and its morphology, which affect critical quality parameters such as shrinkage and warpage. In this paper, the relationship between polymer properties and the propagation of ultrasonic waves is described and the application of ultrasound measurements in injection moulding is evaluated. The principles and operation of both conventional and high-temperature ultrasound transducers are reviewed (HTUTs) together with their impact on improving the efficiency of the injection moulding process. The benefits and challenges associated with the recent development of sol-gel methods for HTUT fabrication are described together with a synopsis of further research and development needed to ensure greater industrial uptake of ultrasonic sensing in injection moulding
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