Creatine and guanidinoacetate reference values in a French population

Creatine and guanidinoacetate are biomarkers of creatine metabolism. Their assays in body fluids may be used for detecting patients with primary creatine deficiency disorders (PCDD), a class of inherited diseases. Their laboratory values in blood and urine may vary with age, requiring that reference normal values are given within the age range. Despite the long known role of creatine for muscle physiology, muscle signs are not necessarily the major complaint expressed by PCDD patients. These disorders drastically affect brain function inducing, in patients, intellectual disability, autistic behavior and other neurological signs (delays in speech and language, epilepsy, ataxia, dystonia and choreoathetosis), being a common feature the drop in brain creatine content. For this reason, screening of PCDD patients has been repeatedly carried out in populations with neurological signs. This report is aimed at providing reference laboratory values and related age ranges found for a large scale population of patients with neurological signs (more than 6 thousand patients) previously serving as a background population for screening French patients with PCDD. These reference laboratory values and age ranges compare rather favorably with literature values for healthy populations. Some differences are also observed, and female participants are discriminated from male participants as regards to urine but not blood values including creatine on creatinine ratio and guanidinoacetate on creatinine ratio values. Such gender differences were previously observed in healthy populations; they might be explained by literature differential effects of testosterone and estrogen in adolescents and adults, and by estrogen effects in prepubertal age on SLC6A8 function. Finally, though they were acquired on a population with neurological signs, the present data might reasonably serve as reference laboratory values in any future medical study exploring abnormalities of creatine metabolism and transport

Human genetics and clinical aspects of neurodevelopmental disorders

This chapter traverses contemporary understandings of the genetic architecture of human disease, and explores the clinical implications of the current state of knowledge. Many different classes of genetic mutations have been implicated as being involved in predisposition to certain diseases, and researchers are continually uncovering other means by which genetics plays an important role in human disease, such as with somatic genetic mosaicism. Putative “de novo” mutations can represent cases of parental mosaicism (including in the germline), which could be revealed by careful genotyping of parental tissues other than peripheral blood lymphocytes. There is an increasingly rich literature regarding rare mutations with seemingly large phenotypic effects. Privacy concerns have added to the difficulties of implementing genomics-guided medicine. With the advent of exome and whole genome sequencing (WGS), one needs to focus again on families over several generations, so as to attempt to minimize genetic differences, locus heterogeneity and environmental influences

Quality of life in men with Klinefelter syndrome: a multicentre study

Background: Klinefelter syndrome (KS) is associated with an increased risk of lower socioeconomic status and a higher risk for morbidity and mortal ity, which may have a significant impact on quality of life (QOL). The objective of this study is to investigate QOL in a large European cohort of men with KS. Design: Cross-sectional multicentre study. Methods: Two-hundred-eighteen men with KS were recruited from 14 clinic al study centres in 6 European countries which participated in the Europ ean dsd-LIFE study. Male normative data from a healthy and a psychiatric reference population were used for comparison. The validated World Health Organization (WHO) Q OL (WHOQOL)-BREF questionnaire was used to investigate five main domains of quali ty of life (WHOQOL): global, physical, psychological, environment, and social. Results: The QOL physical domain score was lower for men with KS compar ed to the healthy reference population (KS: 66.9; s.d. 19.4, n = 193; healthy reference population: 76.5; s.d. 16.2, n = 1324, P < 0.001) but higher compared to the psychiatric reference population (54.6; s.d. 20.6; n = 77, P < 0.001). The WHOQOL-psychological domain score was lower for men with KS compared to the healthy reference pop ulation (KS: 63.6; s.d. 17.8, n = 193; healthy reference population: 67.8; s.d. 15.6, n = 1324, P < 0.05) but higher compared to the psychiatric reference population (45.9; s.d. 26.0), n = 77, P < 0.001). The social domain score on the WHOQOL questionnaire was found t o be lower in men with Klinefelter syndrome (KS) compared to the healthy referenc e population (KS: 60.0; s.d. 21.6, n = 193; healthy reference population: 68.2; s.d. 13.8, n = 1324, P < 0.001). However, this score was similar to that of the psychiatric refe rence population (61.0; s.d. 17.0, n = 77, P = 0.5). The WHO environment domain score of men with KS (70.0; s.d. 15.0, n = 193) was similar to the healthy reference population (70.5; s.d. 20.7, n = 1324) but higher compared to the psychiatric reference population (61 .9; s.d. 20.8, n = 77, P = 0.002). Experienced discrimination, less social activities, and the presence of chronic health problems were associated with significantly decreased QOL in men with KS. Conclusion: Overall QOL in European men with KS is significantly worse comp ared to a healthy European reference population. Especially, the presen ce of discrimination, less social activities, and chronic health problems is associat ed with lower physical, psychological, and social QOL. Further studies are necessary to investigate if a multidisciplinary approach may help to provide adequate counsel ling and psychosocial support to improve QOL

A homozygous ATAD1 mutation impairs postsynaptic AMPA receptor trafficking and causes a lethal encephalopathy

Members of the AAA+ superfamily of ATPases are involved in the unfolding of proteins and disassembly of protein complexes and aggregates. ATAD1 encoding the ATPase family, AAA+ domain containing 1-protein Thorase plays an important role in the function and integrity of mitochondria and peroxisomes. Postsynaptically, Thorase controls the internalization of excitatory, glutamatergic AMPA receptors by disassembling complexes between the AMPA receptor-binding protein, GRIP1, and the AMPA receptor subunit GluA2. Using whole-exome sequencing, we identified a homozygous frameshift mutation in the last exon of ATAD1 [c.1070-1071delAT; p.(His357Argfs 1715)] in three siblings who presented with a severe, lethal encephalopathy associated with stiffness and arthrogryposis. Biochemical and cellular analyses show that the C-terminal end of Thorase mutant gained a novel function that strongly impacts its oligomeric state, reduces stability or expression of a set of Golgi, peroxisomal and mitochondrial proteins and affects disassembly of GluA2 and Thorase oligomer complexes. Atad1 -/- neurons expressing Thorase mutant His357Argfs 1715 display reduced amount of GluA2 at the cell surface suggesting that the Thorase mutant may inhibit the recycling back and/or reinsertion of AMPA receptors to the plasma membrane. Taken together, our molecular and functional analyses identify an activating ATAD1 mutation as a new cause of severe encephalopathy and congenital stiffness

Closure and the Book of Virgil

Taking its initial inspiration from Lipking’s first foray into what is now known as ‘career criticism’ this chapter considers the ‘wheel of Virgil’ and the works of the poet’s ancient biographers in structuring structuring readers’ understanding of his three canonical works and of the connections between them. Rejecting the idea that the career pattern necessarily means that we must see Virgil as progressing towards ever greater acceptance of the political realities of his day, the chapter instead looks to different models of reading, in which attention to intratextual echoes prevents purely linear and teleological interpretations. It is proposed that the Book of Virgil demands a circular rather than a linear pattern of reading, and that the role played by the image of shade and darkness, and the word umbra in particular, is to unify the three works in rejecting the triumph of epic and empir

SLC10A7 mutations cause a skeletal dysplasia with amelogenesis imperfecta mediated by GAG biosynthesis defects.

Skeletal dysplasia with multiple dislocations are severe disorders characterized by dislocations of large joints and short stature. The majority of them have been linked to pathogenic variants in genes encoding glycosyltransferases, sulfotransferases or epimerases required for glycosaminoglycan synthesis. Using exome sequencing, we identify homozygous mutations in SLC10A7 in six individuals with skeletal dysplasia with multiple dislocations and amelogenesis imperfecta. SLC10A7 encodes a 10-transmembrane-domain transporter located at the plasma membrane. Functional studies in vitro demonstrate that SLC10A7 mutations reduce SLC10A7 protein expression. We generate a Slc10a7-/- mouse model, which displays shortened long bones, growth plate disorganization and tooth enamel anomalies, recapitulating the human phenotype. Furthermore, we identify decreased heparan sulfate levels in Slc10a7-/- mouse cartilage and patient fibroblasts. Finally, we find an abnormal N-glycoprotein electrophoretic profile in patient blood samples. Together, our findings support the involvement of SLC10A7 in glycosaminoglycan synthesis and specifically in skeletal development

A Solve-RD ClinVar-based reanalysis of 1522 index cases from ERN-ITHACA reveals common pitfalls and misinterpretations in exome sequencing

Purpose Within the Solve-RD project (https://solve-rd.eu/), the European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies aimed to investigate whether a reanalysis of exomes from unsolved cases based on ClinVar annotations could establish additional diagnoses. We present the results of the “ClinVar low-hanging fruit” reanalysis, reasons for the failure of previous analyses, and lessons learned. Methods Data from the first 3576 exomes (1522 probands and 2054 relatives) collected from European Reference Network for Intellectual disability, TeleHealth, Autism and Congenital Anomalies was reanalyzed by the Solve-RD consortium by evaluating for the presence of single-nucleotide variant, and small insertions and deletions already reported as (likely) pathogenic in ClinVar. Variants were filtered according to frequency, genotype, and mode of inheritance and reinterpreted. Results We identified causal variants in 59 cases (3.9%), 50 of them also raised by other approaches and 9 leading to new diagnoses, highlighting interpretation challenges: variants in genes not known to be involved in human disease at the time of the first analysis, misleading genotypes, or variants undetected by local pipelines (variants in off-target regions, low quality filters, low allelic balance, or high frequency). Conclusion The “ClinVar low-hanging fruit” analysis represents an effective, fast, and easy approach to recover causal variants from exome sequencing data, herewith contributing to the reduction of the diagnostic deadlock

Les structures de peuplement en Ribagorce dans les vallées de la noguera ribagorçana et de l’Isábena (ixe-xie siècles)

Après l’invasion de la péninsule Ibérique au VIIIe siècle, les Pyrénées délimitent une zone de frontière entre les terres carolingiennes et le monde arabo-musulman. La Ribagorce sépare également la Catalogne, à l’est, du royaume navarro-aragonais, à l’ouest. Eloignée des grands axes de communication et centres politiques, cette bande de montagne offre des conditions de vie extrêmes. Son isolement et son enclavement en font, dès la période romaine, un lieu de refuge qui subit peu les évolution..

Les satires d'Horace (troisième et dernier article)

Cartault Auguste. Les satires d'Horace (troisième et dernier article). In: Journal des savants. 10ᵉ année, Novembre 1912. pp. 490-503