626 research outputs found
Growth disrupting mutations in epigenetic regulatory molecules are associated with abnormalities of epigenetic aging.
Germline mutations in fundamental epigenetic regulatory molecules including DNA methyltransferase 3 alpha (DNMT3A) are commonly associated with growth disorders, whereas somatic mutations are often associated with malignancy. We profiled genome-wide DNA methylation patterns in DNMT3A c.2312G > A; p.(Arg771Gln) carriers in a large Amish sibship with Tatton-Brown-Rahman syndrome (TBRS), their mosaic father, and 15 TBRS patients with distinct pathogenic de novo DNMT3A variants. This defined widespread DNA hypomethylation at specific genomic sites enriched at locations annotated as genes involved in morphogenesis, development, differentiation, and malignancy predisposition pathways. TBRS patients also displayed highly accelerated DNA methylation aging. These findings were most marked in a carrier of the AML-associated driver mutation p.Arg882Cys. Our studies additionally defined phenotype-related accelerated and decelerated epigenetic aging in two histone methyltransferase disorders: NSD1 Sotos syndrome overgrowth disorder and KMT2D Kabuki syndrome growth impairment. Together, our findings provide fundamental new insights into aberrant epigenetic mechanisms, the role of epigenetic machinery maintenance, and determinants of biological aging in these growth disorders
The Tatton-Brown-Rahman Syndrome: A clinical study of 55 individuals with de novo constitutive DNMT3A variants.
Tatton-Brown-Rahman syndrome (TBRS; OMIM 615879), also known as the DNMT3A-overgrowth syndrome, is an overgrowth intellectual disability syndrome first described in 2014 with a report of 13 individuals with constitutive heterozygous DNMT3A variants. Here we have undertaken a detailed clinical study of 55 individuals with de novoDNMT3A variants, including the 13 previously reported individuals. An intellectual disability and overgrowth were reported in >80% of individuals with TBRS and were designated major clinical associations. Additional frequent clinical associations (reported in 20-80% individuals) included an evolving facial appearance with low-set, heavy, horizontal eyebrows and prominent upper central incisors; joint hypermobility (74%); obesity (weight ³2SD, 67%); hypotonia (54%); behavioural/psychiatric issues (most frequently autistic spectrum disorder, 51%); kyphoscoliosis (33%) and afebrile seizures (22%). One individual was diagnosed with acute myeloid leukaemia in teenage years. Based upon the results from this study, we present our current management for individuals with TBRS
No COVID-19 pandemic impact on incidence and clinical presentation of celiac disease in Italian children
Aim: We aimed to evaluate the impact of Coronavirus Disease-19 (COVID-19) pandemic on the incidence and clinical presentation of celiac disease (CD) in children.MethodsThe diagnoses of CD were compared between the COVID-19 pandemic (from April 2020 to March 2022) and the pre-pandemic period (from April 2018 to March 2020) in three Italian Paediatric Gastroenterology centres (Varese, Como, Catanzaro). Electronic patient records were reviewed and additional information were collected through parental interview. The diagnosis of CD was made according to ESPGHAN criteria. SARS-CoV-2 infection was diagnosed based on pre-vaccination positive serum antibodies or nasopharyngeal swabs. Z test and chi-square were used for statistical analysis.ResultsThe overall number of paediatric diagnosis of CD did not differ between the two years pre-pandemic and pandemic periods (177 and 172 cases) in the three Italian participating centres. Clinical presentation of CD was also similar throughout the study periods. SARS-CoV-2 infection has been documented in 10.6% of children but only in 5.8% of these occurred before CD diagnosis.ConclusionDifferent to what reported for other autoimmune diseases, the incidence and presenting symptoms of CD in our paediatric population did not change during the COVID-19 pandemic compared to the previous 2 years
The cooling of atomic and molecular gas in DR21
We present an overview of a high-mass star formation region through the major
(sub-)mm, and far-infrared cooling lines to gain insight into the physical
conditions and the energy budget of the molecular cloud. We used the KOSMA 3m
telescope to map the core () of the Galactic star forming region
DR 21/DR 21 (OH) in the Cygnus X region in the two fine structure lines of
atomic carbon CI and four mid- transitions of CO and CO, and CS
J=7\TO6. These observations have been combined with FCRAO J=1\TO0
observations of CO and CO. Five positions, including DR21, DR21
(OH), and DR21 FIR1, were observed with the ISO/LWS grating spectrometer in the
\OI 63 and 145 m lines, the \CII 158 m line, and four high- CO
lines. We discuss the intensities and line ratios at these positions and apply
Local Thermal Equilibrium (LTE) and non-LTE analysis methods in order to derive
physical parameters such as masses, densities and temperatures. The CO line
emission has been modeled up to J=20. From non-LTE modeling of the low- to
high- CO lines we identify two gas components, a cold one at temperatures of
T_\RM{kin}\sim 30-40 K, and one with T_\RM{kin}\sim 80-150 K at a local
clump density of about n(H) cm. While the cold
quiescent component is massive containing typically more than 94 % of the mass,
the warm, dense, and turbulent gas is dominated by mid- and high- CO line
emission and its large line widths. The medium must be clumpy with a
volume-filling of a few percent. The CO lines are found to be important for the
cooling of the cold molecular gas, e.g. at DR21 (OH). Near the outflow of the
UV-heated source DR21, the gas cooling is dominated by line emission of atomic
oxygen and of CO
Modulating the WNT pathway in Drosophila models of Cornelia de Lange Syndrome
Cornelia de Lange syndrome (CdLS) is a rare genetic disorder affecting neurodevelopment and the gastrointestinal, musculoskeletal systems. CdLS is caused by mutations within NIPBL, SMC1A, SMC3, RAD21, and HDAC8 genes. These genes codify for the cohesin complex, a multiprotein structure playing a role in chromatid adhesion, DNA repair and gene expression regulation. It has been demonstrated that a strong correlation exists between cohesin complex function and WNT signalling, an intracellular pathway involved in regulation of expression of several genes controlling cell division and embryonic development.
Recently, it has been observed that chemical activation of the WNT pathway in nipblb-loss-of-function zebrafish embryos and in NIPBL-mutated patient fibroblasts rescued the adverse phenotype. Both embryos and fibroblasts present similar patterns of canonical WNT pathway alterations and cyclinD1 downregulation.
Drosophila melanogaster is an inexpensive model to study CdLS and to screen in vivo for therapeutic compounds. Therefore, we have used flies strains mutated in Nipped-B and Hdac3 genes (respectively NIPBL and HDAC8 in humans) for assessing the existing correlation between cohesin complex and WNT pathway. Moreover, we have selected D. melanogaster mutants to screen for chemicals that revert the CdLS associated-phenotypes efficiently. In particular, we have tested several WNT activators and differences in modulating CdLS phenotypes will be discussed
Drosophila melanogaster as a model to study WNT pathway alteration in Cornelia de Lange Syndrome
Introduction: Cornelia de Lange syndrome (CdLS) is a rare genetic disorder affecting neurodevelopment, gastrointestinal and musculoskeletal systems. CdLS is caused by mutations within NIPBL, SMC1A, SMC3, RAD21, or HDAC8 genes. These genes codify for the cohesin complex, a multiprotein structure playing a role in chromatid adhesion, DNA repair and gene expression regulation. It has been demonstrated that a strong correlation exists between cohesin complex function and WNT signalling. Recently, it has been observed that chemical activation of the WNT pathway in nipblb-loss-of-function zebrafish embryos and in NIPBL-mutated patient fibroblasts rescued the adverse phenotype. Both embryos and fibroblasts present similar patterns of canonical WNT pathway alterations and CCND1 downregulation.
Materials and Methods: Drosophila melanogaster is an inexpensive model to study CdLS and to screen in vivo for therapeutic compounds. Therefore, we have selected fly strains mutated in nipped-B and hdac3 genes (respectively NIPBL and HDAC8 in humans) for assessing the existing correlation between cohesin complex and WNT pathway and to screen for chemicals that revert the CdLS associated-phenotypes efficiently.
Results: We have confirmed that mutated flies weight 5% less than wild type. Moreover, we have tested lithium chloride (LiCl) as WNT activator, demonstrating that 250mM is the highest concentration tolerated.
Conclusions: Hence, we hypothesize that WNT pathway activation could improve mutant phenotype. We will be testing different doses of LiCl and other WNT activator to assess whether some of those chemical compounds could revert the syndrome-associated phenotype
The clinical management of children with achondroplasia in Italy: results of clinician and parent/caregiver surveys
Purpose: This study aimed to assess the real-world management of achondroplasia in Italy. Methods: Two online surveys addressed to (1) parents/caregivers of individuals with achondroplasia and (2) Italian clinicians managing individuals with achondroplasia were conducted to assess real-world perspectives on achondroplasia management. Both surveys collected data on either patient or clinician demographics, details on diagnoses and referrals, disease complications, and views/experiences with limb lengthening surgery. Results: In total, 42 parents/caregivers and 19 clinicians (from 18 hospitals) completed the surveys. According to parents/caregivers, achondroplasia diagnosis was most commonly made in the third trimester of gestation (55% of respondents), with a genetic test performed to confirm the diagnosis in all but one case. In contrast, the clinicians indicated that, while achondroplasia was typically suspected during the prenatal period (78%), diagnosis was more frequently confirmed postnatally (72%). Parents/caregivers reported that the greatest impact of achondroplasia-related complications occurred in their children between the ages of 2-5 years. The most significant complications were otitis, sleep apnoea, stenosis of the foramen magnum or pressure on the spinal cord, and hearing difficulties. Lengthening surgery had been presented as a treatment option to 92% of responding parents/caregivers, with 76% of clinicians viewing surgery favourably. Typically, clinicians' reasons for suggesting limb lengthening surgery were to improve patient quality of life, increase patient autonomy and self-acceptance, improve trunk-limb disproportion, short stature and walking, and ensure that all possible treatment options had been presented to the parents/caregivers. Conclusion: This survey provides insight into the real-world management of individuals with achondroplasia in Italy
Targeted Next-Generation Sequencing Analysis of 1,000 Individuals with Intellectual Disability.
To identify genetic causes of intellectual disability (ID), we screened a cohort of 986 individuals with moderate to severe ID for variants in 565 known or candidate ID-associated genes using targeted next-generation sequencing. Likely pathogenic rare variants were found in ∼11% of the cases (113 variants in 107/986 individuals: ∼8% of the individuals had a likely pathogenic loss-of-function [LoF] variant, whereas ∼3% had a known pathogenic missense variant). Variants in SETD5, ATRX, CUL4B, MECP2, and ARID1B were the most common causes of ID. This study assessed the value of sequencing a cohort of probands to provide a molecular diagnosis of ID, without the availability of DNA from both parents for de novo sequence analysis. This modeling is clinically relevant as 28% of all UK families with dependent children are single parent households. In conclusion, to diagnose patients with ID in the absence of parental DNA, we recommend investigation of all LoF variants in known genes that cause ID and assessment of a limited list of proven pathogenic missense variants in these genes. This will provide 11% additional diagnostic yield beyond the 10%-15% yield from array CGH alone.Action Medical Research (SP4640); the Birth Defect Foundation (RG45448); the Cambridge National Institute for Health Research Biomedical Research Centre (RG64219); the NIHR Rare Diseases BioResource (RBAG163); Wellcome Trust award WT091310; The Cell lines and DNA bank of Rett Syndrome, X-linked mental retardation and other genetic diseases (member of the Telethon Network of Genetic Biobanks (project no. GTB12001); the Genetic Origins of Congenital Heart Disease Study (GO-CHD)- funded by British Heart Foundation (BHF)This is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1002/humu.2290
Children with special health care needs attending emergency department in Italy: analysis of 3479 cases
Background Although children with special health care needs (CSHCN) represent a minority of the population, they go through more hospitalizations, more admissions to the Emergency Department (ED), and receive a major number of medical prescriptions, in comparison to general pediatric population. Objectives of the study were to determine the reasons for admission to the ED in Italian CSHCN, and to describe the association between patient's demographic data, clinical history, and health services requirements. Methods Ad hoc web site was created to collect retrospective data of 3479 visits of CSHCN to the ED in 58 Italian Hospitals. Results Seventy-two percent of patients admitted to ED were affected by a previously defined medical condition. Most of the ED admissions were children with syndromic conditions (54%). 44.2% of the ED admissions were registered during the night-time and/or at the weekends. The hospitalization rate was of 45.6% among patients admitted to the ED. The most common reason for admission to the ED was the presence of respiratory symptoms (26.6%), followed by gastrointestinal problems (21.3%) and neurological disorders (18.2%). 51.4% of the access were classified as 'urgent', with a red/yellow triage code. Considering the type of ED, 61.9% of the visits were conducted at the Pediatric EDs (PedEDs), 33.5% at the Functional EDs (FunEDs) and 4.6% at the Dedicated EDs (DedEDs). Patients with more complex clinical presentation were more likely to be evaluated at the PedEDs. CSHCN underwent to a higher number of medical procedures at the PedEDs, more in comparison to other EDs. Children with medical devices were directed to a PedED quite exclusively when in need for medical attention. Subjects under multiple anti-epileptic drug therapy attended to PedEDs or FunEDs generally. Patients affected by metabolic diseases were more likely to look for medical attention at FunEDs. Syndromic patients mostly required medical attention at the DedEDs. Conclusions Access of CSHCN to an ED is not infrequent. For this reason, it is fundamental for pediatricians working in any kind of ED to increase their general knowledge about CHSCN and to gain expertise in the management of such patients and their related medical complexity
EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF); Scientific Opinion on Flavouring Group Evaluation 96 (FGE.96): Consideration of 88 flavouring substances considered by EFSA for which EU production volumes / anticipated production volumes have been submitted on request by DG SANCO. Addendum to FGE. 51, 52, 53, 54, 56, 58, 61, 62, 63, 64, 68, 69, 70, 71, 73, 76, 77, 79, 80, 83, 84, 85 and 87
Overgrowth disorders are a heterogeneous group of conditions characterized by increased growth parameters and other variable clinical features such as intellectual disability and facial dysmorphism1. To identify new causes of human overgrowth, we performed exome sequencing in ten proband-parent trios and detected two de novo DNMT3A mutations. We identified 11 additional de novo mutations by sequencing DNMT3A in a further 142 individuals with overgrowth. The mutations alter residues in functional DNMT3A domains, and protein modeling suggests that they interfere with domain-domain interactions and histone binding. Similar mutations were not present in 1,000 UK population controls (13/152 cases versus 0/1,000 controls; P < 0.0001). Mutation carriers had a distinctive facial appearance, intellectual disability and greater height. DNMT3A encodes a DNA methyltransferase essential for establishing methylation during embryogenesis and is commonly somatically mutated in acute myeloid leukemia2, 3, 4. Thus, DNMT3A joins an emerging group of epigenetic DNA- and histone-modifying genes associated with both developmental growth disorders and hematological malignancie
- …
