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1.
Am J Med Genet A ; 194(5): e63516, 2024 May.
Article in English | MEDLINE | ID: mdl-38168088

ABSTRACT

The NFIX gene encodes a DNA-binding protein belonging to the nuclear factor one (NFI) family of transcription factors. Pathogenic variants of NFIX are associated with two autosomal dominant Mendelian disorders, Malan syndrome (MIM 614753) and Marshall-Smith syndrome (MIM 602535), which are clinically distinct due to different disease-causing mechanisms. NFIX variants associated with Malan syndrome are missense variants mostly located in exon 2 encoding the N-terminal DNA binding and dimerization domain or are protein-truncating variants that trigger nonsense-mediated mRNA decay (NMD) resulting in NFIX haploinsufficiency. NFIX variants associated with Marshall-Smith syndrome are protein-truncating and are clustered between exons 6 and 10, including a recurrent Alu-mediated deletion of exons 6 and 7, which can escape NMD. The more severe phenotype of Marshall-Smith syndrome is likely due to a dominant-negative effect of these protein-truncating variants that escape NMD. Here, we report a child with clinical features of Malan syndrome who has a de novo NFIX intragenic duplication. Using genome sequencing, exon-level microarray analysis, and RNA sequencing, we show that this duplication encompasses exons 6 and 7 and leads to NFIX haploinsufficiency. To our knowledge, this is the first reported case of Malan Syndrome caused by an intragenic NFIX duplication.


Subject(s)
Abnormalities, Multiple , Bone Diseases, Developmental , Craniofacial Abnormalities , Intellectual Disability , Megalencephaly , Septo-Optic Dysplasia , Sotos Syndrome , Child , Humans , NFI Transcription Factors/genetics , Sotos Syndrome/genetics , Exons/genetics , Megalencephaly/genetics , Intellectual Disability/genetics , Sequence Analysis, RNA
2.
Pediatr Res ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38969815

ABSTRACT

BACKGROUND: Despite advances in treatment and survival, individuals with congenital heart defects (CHD) have a higher risk of heart failure (HF) compared to the general population. OBJECTIVE: To evaluate comorbidities associated with HF in patients with CHD with a goal of identifying potentially modifiable risk factors that may reduce HF-associated morbidity and mortality. METHODS: Five surveillance sites in the United States linked population-based healthcare data and vital records. Individuals with an ICD-9-CM code for CHD aged 11-64 years were included and were stratified by presence of HF diagnosis code. Prevalence of death and cardiovascular risk factors based on diagnosis codes were compared by HF status using log-linear regression. RESULTS: A total of 25,343 individuals met inclusion/exclusion criteria. HF was documented for 2.2% of adolescents and 12.9% of adults with CHD. Adolescents and adults with HF had a higher mortality than those without HF. In both age groups, HF was positively associated with coronary artery disease, hypertension, obesity, diabetes, and increased healthcare utilization compared to those without HF. CONCLUSIONS: Within this population-based cohort, over 1 in 50 adolescents and 1 in 8 adults with CHD had HF, which was associated with increased mortality. Modifiable cardiovascular comorbidities were associated with HF. IMPACT: Five sites in the United States linked population-based healthcare data and vital records to establish surveillance network for identifying the factors which influence congenital heart disease (CHD) outcomes. Survivors of CHD frequently develop heart failure across the lifespan. Over 1 in 50 adolescent and 1 in 8 adult survivors of CHD have heart failure which is associated with increased mortality compared to CHD survivors without heart failure. Heart failure development is associated with potentially modifiable cardiovascular risk factors such as hypertension, coronary artery disease, and diabetes. Controlling modifiable cardiovascular risk factors may serve to lower the risk of heart failure and mortality in survivors of congenital heart disease of all ages.

3.
Brain ; 146(4): 1357-1372, 2023 04 19.
Article in English | MEDLINE | ID: mdl-36074901

ABSTRACT

The vacuolar H+-ATPase is an enzymatic complex that functions in an ATP-dependent manner to pump protons across membranes and acidify organelles, thereby creating the proton/pH gradient required for membrane trafficking by several different types of transporters. We describe heterozygous point variants in ATP6V0C, encoding the c-subunit in the membrane bound integral domain of the vacuolar H+-ATPase, in 27 patients with neurodevelopmental abnormalities with or without epilepsy. Corpus callosum hypoplasia and cardiac abnormalities were also present in some patients. In silico modelling suggested that the patient variants interfere with the interactions between the ATP6V0C and ATP6V0A subunits during ATP hydrolysis. Consistent with decreased vacuolar H+-ATPase activity, functional analyses conducted in Saccharomyces cerevisiae revealed reduced LysoSensor fluorescence and reduced growth in media containing varying concentrations of CaCl2. Knockdown of ATP6V0C in Drosophila resulted in increased duration of seizure-like behaviour, and the expression of selected patient variants in Caenorhabditis elegans led to reduced growth, motor dysfunction and reduced lifespan. In summary, this study establishes ATP6V0C as an important disease gene, describes the clinical features of the associated neurodevelopmental disorder and provides insight into disease mechanisms.


Subject(s)
Epilepsy , Vacuolar Proton-Translocating ATPases , Humans , Vacuolar Proton-Translocating ATPases/genetics , Vacuolar Proton-Translocating ATPases/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Epilepsy/genetics , Adenosine Triphosphate
4.
PLoS Genet ; 17(3): e1009413, 2021 03.
Article in English | MEDLINE | ID: mdl-33684136

ABSTRACT

Previous research on risk factors for obstructive heart defects (OHDs) focused on maternal and infant genetic variants, prenatal environmental exposures, and their potential interaction effects. Less is known about the role of paternal genetic variants or environmental exposures and risk of OHDs. We examined parent-of-origin effects in transmission of alleles in the folate, homocysteine, or transsulfuration pathway genes on OHD occurrence in offspring. We used data on 569 families of liveborn infants with OHDs born between October 1997 and August 2008 from the National Birth Defects Prevention Study to conduct a family-based case-only study. Maternal, paternal, and infant DNA were genotyped using an Illumina Golden Gate custom single nucleotide polymorphism (SNP) panel. Relative risks (RR), 95% confidence interval (CI), and likelihood ratio tests from log-linear models were used to estimate the parent-of-origin effect of 877 SNPs in 60 candidate genes in the folate, homocysteine, and transsulfuration pathways on the risk of OHDs. Bonferroni correction was applied for multiple testing. We identified 3 SNPs in the transsulfuration pathway and 1 SNP in the folate pathway that were statistically significant after Bonferroni correction. Among infants who inherited paternally-derived copies of the G allele for rs6812588 in the RFC1 gene, the G allele for rs1762430 in the MGMT gene, and the A allele for rs9296695 and rs4712023 in the GSTA3 gene, RRs for OHD were 0.11 (95% CI: 0.04, 0.29, P = 9.16x10-7), 0.30 (95% CI: 0.17, 0.53, P = 9.80x10-6), 0.34 (95% CI: 0.20, 0.57, P = 2.28x10-5), and 0.34 (95% CI: 0.20, 0.58, P = 3.77x10-5), respectively, compared to infants who inherited maternally-derived copies of the same alleles. We observed statistically significant decreased risk of OHDs among infants who inherited paternal gene variants involved in folate and transsulfuration pathways.


Subject(s)
Genetic Predisposition to Disease , Genetic Variation , Heart Defects, Congenital/genetics , Inheritance Patterns , Adult , Alleles , Cardiomyopathy, Hypertrophic, Familial/genetics , Chromosome Mapping , Female , Genotype , Heart Defects, Congenital/epidemiology , Heart Defects, Congenital/metabolism , Humans , Male , Middle Aged , Odds Ratio , Phenotype , Polymorphism, Single Nucleotide , Risk Assessment , Young Adult
5.
Ann Neurol ; 92(5): 895-901, 2022 11.
Article in English | MEDLINE | ID: mdl-35947102

ABSTRACT

NOTCH1 belongs to the NOTCH family of proteins that regulate cell fate and inflammatory responses. Somatic and germline NOTCH1 variants have been implicated in cancer, Adams-Oliver syndrome, and cardiovascular defects. We describe 7 unrelated patients grouped by the presence of leukoencephalopathy with calcifications and heterozygous de novo gain-of-function variants in NOTCH1. Immunologic profiling showed upregulated CSF IP-10, a cytokine secreted downstream of NOTCH1 signaling. Autopsy revealed extensive leukoencephalopathy and microangiopathy with vascular calcifications. This evidence implicates that heterozygous gain-of-function variants in NOTCH1 lead to a chronic central nervous system (CNS) inflammatory response resulting in a calcifying microangiopathy with leukoencephalopathy. ANN NEUROL 2022;92:895-901.


Subject(s)
Ectodermal Dysplasia , Leukoencephalopathies , Humans , Receptor, Notch1/genetics , Receptor, Notch1/metabolism , Chemokine CXCL10 , Central Nervous System/metabolism
6.
J Pediatr ; 240: 79-86.e1, 2022 01.
Article in English | MEDLINE | ID: mdl-34508749

ABSTRACT

OBJECTIVES: To assess associations between maternal smoking and congenital heart defects (CHDs) in offspring. STUDY DESIGN: We performed a retrospective case-control study using data for cases of CHD (n = 8339) and nonmalformed controls (n = 11 020) from all years (1997-2011) of the National Birth Defects Prevention Study. Maternal self-reported smoking 1 month before through 3 months after conception was evaluated as a binary (none, any) and categorical (light, medium, heavy) exposure. Multivariable logistic regression was used to estimate aOR and 95% CIs. Stratified analyses were performed for septal defects according to maternal age, prepregnancy body mass index, and maternal race/ethnicity. RESULTS: Multiple CHDs displayed modest associations with any level of maternal periconceptional smoking independent of potential confounders; the strongest associations were for aggregated septal defects (OR, 1.5; 95% CI, 1.3-1.7), tricuspid atresia (OR, 1.7; 95% CI, 1.0-2.7), and double outlet right ventricle (DORV) (OR, 1.5; 95% CI, 1.1-2.1). Tricuspid atresia and DORV also displayed dose-response relationships. Among heavy smokers, the highest odds were again observed for tricuspid atresia (aOR 3.0; 95% CI, 1.5-6.1) and DORV (aOR 1.5; 95% CI, 1.1-2.2). Heavy smokers ≥35 years old more frequently had a child with a septal defect when compared with similarly aged nonsmokers (aOR 2.3; 95% CI, 1.4-3.9). CONCLUSIONS: Maternal periconceptional smoking is most strongly associated with septal defects, tricuspid atresia, and DORV; the risk for septal defects is modified by maternal age.


Subject(s)
Cannabis , Heart Defects, Congenital , Prenatal Exposure Delayed Effects , Adult , Aged , Case-Control Studies , Child , Female , Heart Defects, Congenital/epidemiology , Heart Defects, Congenital/etiology , Humans , Infant , Pregnancy , Prenatal Exposure Delayed Effects/epidemiology , Retrospective Studies , Risk Assessment , Risk Factors , Smoking/adverse effects
7.
Soft Matter ; 18(20): 3967-3980, 2022 May 25.
Article in English | MEDLINE | ID: mdl-35551304

ABSTRACT

Combining molecular dynamics (MD) and continuum simulations, we study the dynamics of propagation of a peeling front in a system composed of multilayered graphene nanosheets completely immersed in water. Peeling is induced by lifting one of the nanosheet edges with an assigned pulling velocity normal to the flat substrate. Using MD, we compute the pulling force as a function of the pulling velocity, and quantify the viscous resistance to the advancement of the peeling front. We compare the MD results to a 1D continuum model of a sheet loaded with modelled hydrodynamic loads. Our results show that the viscous dependence of the force on the velocity is negligible below a threshold velocity. Above this threshold, the hydrodynamics is mainly controlled by the viscous resistance associated to the flow near the crack opening, while lubrication forces are negligible owing to the large hydrodynamic slip at the liquid-solid boundary. Two dissipative mechanisms are identified: a drag resistance to the upward motion of the edge, and a resistance to the gap opening associated to the curvature of the flow streamlines near the entrance. Surprisingly, the shape of the sheet was found to be approximately independent of the pulling velocity even for the largest velocities considered.

8.
Am J Med Genet C Semin Med Genet ; 187(2): 199-212, 2021 06.
Article in English | MEDLINE | ID: mdl-33982868

ABSTRACT

People with skeletal dysplasias have left traces in art and antiquities through ages and cultures worldwide, in Ancient Egypt, Classical Greece, Sub-Saharan Africa, Asia, and Europe. Such traces record the impact of people with skeletal dysplasia on society and culture-in daily life, religion, and mythology. However, identifying ("diagnosing") skeletal dysplasia in artifacts and interpreting what such depictions meant within the culture in which they were created is extremely challenging and at times impossible. The objectives of this short and necessarily selective survey are to present a few examples of art through different ages and cultures as a springboard for discussion not only on potential medical diagnoses but also on the lives of people with chondrodysplasia and how they were valued in the society in which they lived. The artifacts were selected from Ancient Egypt, Classical Greece, Mesoamerica (Maya), Sub-Saharan Africa (Kingdom of Benin), Tang China, and 17th Century Europe. In some cases, surviving artifacts with likely depictions of skeletal dysplasia are few and their cultural context incompletely understood. Nevertheless, certain themes and attitudes seem to repeat across different times and regions, though some cultures, such as those in Ancient Egypt, appeared to have had a comparatively positive view of people with restricted growth and chondrodysplasia.


Subject(s)
Musculoskeletal Abnormalities , Osteochondrodysplasias , Asia , China , Europe , Humans
9.
Am Heart J ; 238: 100-108, 2021 08.
Article in English | MEDLINE | ID: mdl-33951414

ABSTRACT

BACKGROUND: Many individuals born with congenital heart defects (CHD) survive to adulthood. However, population estimates of CHD beyond early childhood are limited in the U.S. OBJECTIVES: To estimate the percentage of individuals aged 1-to-64 years at five U.S. sites with CHD documented at a healthcare encounter during a three-year period and describe their characteristics. METHODS: Sites conducted population-based surveillance of CHD among 1 to 10-year-olds (three sites) and 11 to 64-year-olds (all five sites) by linking healthcare data. Eligible cases resided in the population catchment areas and had one or more healthcare encounters during the surveillance period (January 1, 2011-December 31, 2013) with a CHD-related ICD-9-CM code. Site-specific population census estimates from the same age groups and time period were used to assess percentage of individuals in the catchment area with a CHD-related ICD-9-CM code documented at a healthcare encounter (hereafter referred to as CHD cases). Severe and non-severe CHD were based on an established mutually exclusive anatomic hierarchy. RESULTS: Among 42,646 CHD cases, 23.7% had severe CHD and 51.5% were male. Percentage of CHD cases among 1 to 10-year-olds, was 6.36/1,000 (range: 4.33-9.96/1,000) but varied by CHD severity [severe: 1.56/1,000 (range: 1.04-2.64/1,000); non-severe: 4.80/1,000 (range: 3.28-7.32/1,000)]. Percentage of cases across all sites in 11 to 64-year-olds was 1.47/1,000 (range: 1.02-2.18/1,000) and varied by CHD severity [severe: 0.34/1,000 (range: 0.26-0.49/1,000); non-severe: 1.13/1,000 (range: 0.76-1.69/1,000)]. Percentage of CHD cases decreased with age until 20 to 44 years and, for non-severe CHD only, increased slightly for ages 45 to 64 years. CONCLUSION: CHD cases varied by site, CHD severity, and age. These findings will inform planning for the needs of this growing population.


Subject(s)
Heart Defects, Congenital/epidemiology , Medical Record Linkage , Population Surveillance , Adolescent , Adult , Age Distribution , Aged , Catchment Area, Health , Child , Child, Preschool , Colorado/epidemiology , Georgia/epidemiology , Heart Defects, Congenital/ethnology , Heart Defects, Congenital/therapy , Humans , Infant , International Classification of Diseases , Middle Aged , New York/epidemiology , North Carolina/epidemiology , Severity of Illness Index , Sex Distribution , Survivors/statistics & numerical data , Utah/epidemiology , Young Adult
10.
Am J Med Genet A ; 185(2): 517-527, 2021 02.
Article in English | MEDLINE | ID: mdl-33398909

ABSTRACT

Bone dysplasias (osteochondrodysplasias) are a large group of conditions associated with short stature, skeletal disproportion, and radiographic abnormalities of skeletal elements. Nearly all are genetic in origin. We report a series of seven children with similar findings of chondrodysplasia and growth failure following early hematopoietic stem cell transplantation (HSCT) for pediatric non-oncologic disease: hemophagocytic lymphohistiocytosis or HLH (five children, three with biallelic HLH-associated variants [in PRF1 and UNC13D] and one with HLH secondary to visceral Leishmaniasis), one child with severe combined immunodeficiency and one with Omenn syndrome (both children had biallelic RAG1 pathogenic variants). All children had normal growth and no sign of chondrodysplasia at birth and prior to their primary disease. After HSCT, all children developed growth failure, with standard deviation scores for height at or below -3. Radiographically, all children had changes in the spine, metaphyses and epiphyses, compatible with a spondyloepimetaphyseal dysplasia. Genomic sequencing failed to detect pathogenic variants in genes associated with osteochondrodysplasias. We propose that such chondrodysplasia with growth failure is a novel, rare, but clinically important complication following early HSCT for non-oncologic pediatric diseases. The pathogenesis is unknown but could possibly involve loss or perturbation of the cartilage-bone stem cell population.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Lymphohistiocytosis, Hemophagocytic/genetics , Osteochondrodysplasias/genetics , Child , Child, Preschool , Female , Humans , Lymphohistiocytosis, Hemophagocytic/complications , Lymphohistiocytosis, Hemophagocytic/diagnosis , Lymphohistiocytosis, Hemophagocytic/therapy , Male , Membrane Proteins/genetics , Osteochondrodysplasias/complications , Osteochondrodysplasias/diagnosis , Osteochondrodysplasias/therapy , Perforin/genetics , Treatment Outcome
11.
Langmuir ; 37(45): 13322-13330, 2021 Nov 16.
Article in English | MEDLINE | ID: mdl-34723541

ABSTRACT

The adsorption of graphene-oxide (GO) nanoparticles at the interface between water and vapor was analyzed using all-atom molecular simulations for single and multiple particles. For a single GO particle, our results indicate that the adsorption energy does not scale linearly with the surface coverage of oxygen groups, unlike typically assumed for Janus colloids. Our results also show that the surface activity of the particle depends on the number of surface oxygen groups as well as on their distribution: for a given number of oxygen groups, a GO particle with a patched surface was found to be more surface active than a particle with evenly distributed groups. Then, to understand what sets the thickness of GO layers at interfaces, the adsorption energy of a test GO particle was measured in the presence of multiple GO particles already adsorbed at the interface. Our results indicate that in the case of high degree of oxidation, particle-particle interactions at the water-vapor interface hinder the adsorption of the test particle. In the case of a low degree of oxidation, however, clustering and stacking of GO particles dominate the adsorption behavior, and particle-particle interactions favor the adsorption of the test particle. These results highlight the complexity of multiple particle adsorption and the limitations of single-particle adsorption models when applied to GO at a relatively high surface concentration.

12.
Am J Med Genet C Semin Med Genet ; 184(1): 23-35, 2020 03.
Article in English | MEDLINE | ID: mdl-32083404

ABSTRACT

Congenital heart disease (CHD) is common, costly, and critical. Approximately half of all infant deaths due to congenital anomalies are associated with CHD or neural tube defects. As infant mortality improves due to better infection control and peripartum care, congenital anomalies are becoming a key driver of pediatric survival and health. Improving CHD prevention and care globally will play a significant role toward key goals such as United Nation's sustainable development goals (SDGs) of good health and well-being (SDG 3) and reduced inequalities (SDG 10). This review addresses two questions: how can we reinterpret and reframe available data on CHD to spur action in prevention and care? How can we re-engineer how we currently track CHD in populations to efficiently generate new data to assess successes and detect gaps in prevention and care? Answering these questions requires understanding the causal chain of disease, from cause to CHD occurrence to health outcomes. This perspective provides a logical basis for two innovations. First, develop a data-driven message that reframes epidemiologic and clinical data in terms of incentives for action, evidence for change, and strategies for population-wide impact. Second, through partnerships between clinical and public health systems, implement an integrated "triple surveillance," which, in the same population, concurrently tracks the three elements of the causal chain-causes, disease occurrence, health outcomes. By streamlining activities and minimizing operational waste, such systems can have a vital role in improving prevention and care on a population level, including in many low and middle-income countries.


Subject(s)
Heart Defects, Congenital/epidemiology , Heart Defects, Congenital/genetics , Public Health , Heart Defects, Congenital/pathology , Humans , Infant , Infant Mortality , Infant, Newborn
13.
Hum Genet ; 139(8): 1077-1090, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32266521

ABSTRACT

Our previous genome-wide association study (GWAS) for sagittal nonsyndromic craniosynostosis (sNCS) provided important insights into the genetics of midline CS. In this study, we performed a GWAS for a second midline NCS, metopic NCS (mNCS), using 215 non-Hispanic white case-parent triads. We identified six variants with genome-wide significance (P ≤ 5 × 10-8): rs781716 (P = 4.71 × 10-9; odds ratio [OR] = 2.44) intronic to SPRY3; rs6127972 (P = 4.41 × 10-8; OR = 2.17) intronic to BMP7; rs62590971 (P = 6.22 × 10-9; OR = 0.34), located ~ 155 kb upstream from TGIF2LX; and rs2522623, rs2573826, and rs2754857, all intronic to PCDH11X (P = 1.76 × 10-8, OR = 0.45; P = 3.31 × 10-8, OR = 0.45; P = 1.09 × 10-8, OR = 0.44, respectively). We performed a replication study of these variants using an independent non-Hispanic white sample of 194 unrelated mNCS cases and 333 unaffected controls; only the association for rs6127972 (P = 0.004, OR = 1.45; meta-analysis P = 1.27 × 10-8, OR = 1.74) was replicated. Our meta-analysis examining single nucleotide polymorphisms common to both our mNCS and sNCS studies showed the strongest association for rs6127972 (P = 1.16 × 10-6). Our imputation analysis identified a linkage disequilibrium block encompassing rs6127972, which contained an enhancer overlapping a CTCF transcription factor binding site (chr20:55,798,821-55,798,917) that was significantly hypomethylated in mesenchymal stem cells derived from fused metopic compared to open sutures from the same probands. This study provides additional insights into genetic factors in midline CS.


Subject(s)
Bone Morphogenetic Protein 7/genetics , Craniosynostoses/genetics , Genetic Variation , Polymorphism, Single Nucleotide/genetics , Alleles , DNA Methylation , Genes, Reporter , Genetic Predisposition to Disease , Genome-Wide Association Study , Genotype , Humans , Introns/genetics , Linkage Disequilibrium , Promoter Regions, Genetic/genetics , Risk Factors
14.
Mol Genet Metab ; 129(1): 13-19, 2020 01.
Article in English | MEDLINE | ID: mdl-31836396

ABSTRACT

BACKGROUND: Medium-Chain Acyl-CoA Dehydrogenase (MCAD) deficiency is a fatty acid oxidation disorder that can have variable clinical severity. There is still limited information on its clinical presentation and longitudinal history by genotype, and effectiveness of newborn screening (NBS). METHODS: Retrospective data were collected from 90 patients (44 female, 46 male) to compare biochemical data with clinical outcomes. The frequency of adverse events (number of hypoglycemia-related ER visits and admissions) was assessed by genotype (homozygosity or not for the common pathogenic variant, p.Lys329Glu, in the ACADM gene), and method of diagnosis (NBS vs. clinical). RESULTS: MCAD deficiency in Utah was more frequent compared to the United States average (1: 9266 versus 1:17,759 newborns). With age, C8-carnitine did not change significantly whereas C2-carnitine decreased (p < .001), possibly reflecting reduced carnitine supplementation typically seen with age. Children with MCAD deficiency had normal growth. p.Lys329Glu homozygotes had higher NBS C8-carnitine (23.4 ± 19.6 vs. 6.6 ± 3.0 µmol/L) and lifetime plasma C8-carnitine levels (6.2 ± 5 vs. 3.6 ± 1.9 µmol/L) compared to patients with at least one other pathogenic variant (p < .001 for both) and higher transaminases compared to compound heterozygotes (ALT 41.9 ± 6.2 vs. 31.5 ± 3.7 U/L, AST 63.9 ± 5.8 vs. 45.7 ± 1.8 U/L, p < .05 for both). On average, p.Lys329Glu homozygotes had more hypoglycemic events than compound heterozygotes (1.44 versus 0.49 events/patient) as did patients diagnosed clinically compared to those diagnosed by NBS (2.15 versus 0.62 events/patient), though these differences were not statistically significant. Neonatal death was observed before results of newborn screening were available in one patient homozygous for the common p.Lys329Glu pathogenic variant, but severe neonatal complications (hypoglycemia, cardiac arrhythmia) were also seen in patients with other mutations. No irreversible complications were observed after diagnosis in any patient with MCAD deficiency. DISCUSSION: Homozygosity for the common ACADM p.Lys329Glu pathogenic variant was associated with increased levels of C8-carnitine and transaminases. Newborn screening provides the opportunity to reduce morbidity and post-neonatal mortality in all patients with MCAD deficiency, regardless of genotype.


Subject(s)
Acyl-CoA Dehydrogenase/deficiency , Genotype , Homozygote , Lipid Metabolism, Inborn Errors/diagnosis , Neonatal Screening , Acyl-CoA Dehydrogenase/genetics , Adolescent , Adult , Carnitine/blood , Child , Child, Preschool , Female , Genetic Variation , Humans , Infant, Newborn , Lipid Metabolism, Inborn Errors/genetics , Lipid Metabolism, Inborn Errors/mortality , Male , Mutation , Phenotype , Retrospective Studies , Transaminases/blood , United States , Utah , Young Adult
15.
Langmuir ; 36(19): 5400-5407, 2020 May 19.
Article in English | MEDLINE | ID: mdl-32337992

ABSTRACT

The nucleation and growth of liquid droplets on solid substrates have received much attention because of the significant relevance of these multiphase processes to both nature and practical applications. There have been extensive studies on the condensation of water from the air phase on solid substrates. Here, we focus on water diffusion through the oil phase and subsequent settlement on solid substrates because such interfacial droplets are formed. Voronoi diagram analysis is proposed to statistically characterize the size distribution of the growing droplets. It is found that modification of the standard Voronoi diagram is required for systems of interfacial droplets which have a noncircular shape and/or whose centers change with time. The modified Voronoi analysis of the growing droplets provides an automatic quantification of the droplet distribution and reveals that (i) during the nucleation stage, the interfacial droplets do not nucleate at the same time because the nucleation of newly formed droplets competes with the growth of the existing ones; (ii) the growth of interfacial droplets comes from water diffusion from the bulk water layer, and/or from adjacent interfacial droplets, and/or from coalescence of interfacial droplets; and (iii) the sizes of interfacial droplets become more polydispersed on P-glass but more monodispersed on OTS-glass as time goes. This work opens a new perspective on the formation of interfacial droplets at the interface between oil and the solid substrate and demonstrates the capability of an automatic analysis method, which can be potentially applied to similar interfacial multiphase systems.

16.
Am J Obstet Gynecol ; 222(2): 176.e1-176.e11, 2020 02.
Article in English | MEDLINE | ID: mdl-31454511

ABSTRACT

BACKGROUND: Diabetes is associated with an increased risk for many birth defects and is likely to have an increasing impact on birth defect prevalence because of the rise in diabetes in the United States in recent decades. One of the first analyses in which specific birth defects were assessed for their relationship with both pregestational and gestational diabetes used data from the initial 6 years of the National Birth Defects Prevention Study. That analysis reported strong associations for pregestational diabetes with several birth defects, but few exposures among some of the less common birth defects led to unstable estimates with wide confidence intervals. Since that analysis, the study continued to collect data for another 8 years, including information on approximately 19,000 additional cases and 6900 additional controls. OBJECTIVE: Our objective was to use data from the National Birth Defects Prevention Study, the largest population-based birth defects case-control study in the United States, to provide updated and more precise estimates of the association between diabetes and birth defects, including some defects not previously assessed. STUDY DESIGN: We analyzed data on deliveries from October 1997 through December 2011. Mothers of case and control infants were interviewed about their health conditions and exposures during pregnancy, including diagnosis of pregestational (type 1 or type 2) diabetes before the index pregnancy or gestational diabetes during the index pregnancy. Using logistic regression, we separately assessed the association between pregestational and gestational diabetes with specific categories of structural birth defects for which there were at least 3 exposed case infants. For birth defect categories for which there were at least 5 exposed case infants, we calculated odds ratios adjusted for maternal body mass index, age, education, race/ethnicity, and study site; for defect categories with 3 or 4 exposed cases, we calculated crude odds ratios. RESULTS: Pregestational diabetes was reported by 0.6% of mothers of control infants (71 of 11,447) and 2.5% of mothers of case infants (775 of 31,007). Gestational diabetes during the index pregnancy was reported by 4.7% of mothers of control infants (536 of 11,447) and 5.3% of mothers of case infants (1,653 of 31,007). Pregestational diabetes was associated with strong, statistically significant odds ratios (range, 2.5-80.2) for 46 of 50 birth defects considered. The largest odds ratio was observed for sacral agenesis (adjusted odds ratio, 80.2; 95% confidence interval, 46.1-139.3). A greater than 10-fold increased risk was also observed for holoprosencephaly (adjusted odds ratio, 13.1; 95% confidence interval, 7.0-24.5), longitudinal limb deficiency (adjusted odds ratio, 10.1; 95% confidence interval, 6.2-16.5), heterotaxy (adjusted odds ratio, 12.3; 95% confidence interval, 7.3-20.5), truncus arteriosus (adjusted odds ratio, 14.9; 95% confidence interval, 7.6-29.3), atrioventricular septal defect (adjusted odds ratio, 10.5; 95% confidence interval, 6.2-17.9), and single ventricle complex (adjusted odds ratio, 14.7; 95% confidence interval, 8.9-24.3). For gestational diabetes, statistically significant odds ratios were fewer (12 of 56) and of smaller magnitude (range, 1.3- 2.1; 0.5 for gastroschisis). CONCLUSION: Pregestational diabetes is associated with a markedly increased risk for many specific births defects. Because glycemic control before pregnancy is associated with a reduced risk for birth defects, ongoing quality care for persons with diabetes is an important opportunity for prevention.


Subject(s)
Congenital Abnormalities/epidemiology , Diabetes, Gestational/epidemiology , Pregnancy in Diabetics/epidemiology , Abnormalities, Multiple/epidemiology , Adult , Case-Control Studies , Female , Gastroschisis/epidemiology , Heart Defects, Congenital/epidemiology , Holoprosencephaly/epidemiology , Humans , Limb Deformities, Congenital/epidemiology , Meningocele/epidemiology , Nervous System Malformations/epidemiology , Pregnancy , Sacrococcygeal Region/abnormalities , United States/epidemiology , Young Adult
17.
J Chem Phys ; 152(10): 104701, 2020 Mar 14.
Article in English | MEDLINE | ID: mdl-32171224

ABSTRACT

Liquid-phase exfoliation, the use of a sheared liquid to delaminate graphite into few-layer graphene, is a promising technique for the large-scale production of graphene. However, the microscale and nanoscale fluid-structure processes controlling the exfoliation are not fully understood. Here, we perform non-equilibrium molecular dynamics simulations of a defect-free graphite nanoplatelet suspended in a shear flow and measure the critical shear rate γ̇c needed for the exfoliation to occur. We compare γ̇c for different solvents, including water and N-methyl-pyrrolidone, and nanoplatelets of different lengths. Using a theoretical model based on a balance between the work done by viscous shearing forces and the change in interfacial energies upon layer sliding, we are able to predict the critical shear rates γ̇c measured in simulations. We find that an accurate prediction of the exfoliation of short graphite nanoplatelets is possible only if both hydrodynamic slip and the fluid forces on the graphene edges are considered and if an accurate value of the solid-liquid surface energy is used. The commonly used "geometric-mean" approximation for the solid-liquid energy leads to grossly incorrect predictions.

18.
Hum Mutat ; 40(7): 908-925, 2019 07.
Article in English | MEDLINE | ID: mdl-30817854

ABSTRACT

Pathogenic de novo variants in the X-linked gene SLC35A2 encoding the major Golgi-localized UDP-galactose transporter required for proper protein and lipid glycosylation cause a rare type of congenital disorder of glycosylation known as SLC35A2-congenital disorders of glycosylation (CDG; formerly CDG-IIm). To date, 29 unique de novo variants from 32 unrelated individuals have been described in the literature. The majority of affected individuals are primarily characterized by varying degrees of neurological impairments with or without skeletal abnormalities. Surprisingly, most affected individuals do not show abnormalities in serum transferrin N-glycosylation, a common biomarker for most types of CDG. Here we present data characterizing 30 individuals and add 26 new variants, the single largest study involving SLC35A2-CDG. The great majority of these individuals had normal transferrin glycosylation. In addition, expanding the molecular and clinical spectrum of this rare disorder, we developed a robust and reliable biochemical assay to assess SLC35A2-dependent UDP-galactose transport activity in primary fibroblasts. Finally, we show that transport activity is directly correlated to the ratio of wild-type to mutant alleles in fibroblasts from affected individuals.


Subject(s)
Congenital Disorders of Glycosylation/genetics , Monosaccharide Transport Proteins/genetics , Monosaccharide Transport Proteins/metabolism , Uridine Diphosphate Galactose/metabolism , Animals , Biopsy , CHO Cells , Cells, Cultured , Congenital Disorders of Glycosylation/metabolism , Congenital Disorders of Glycosylation/pathology , Cricetulus , Female , Humans , Male , Mutation
19.
Am J Hum Genet ; 99(2): 299-317, 2016 08 04.
Article in English | MEDLINE | ID: mdl-27476657

ABSTRACT

Vascular malformations are non-neoplastic expansions of blood vessels that arise due to errors during angiogenesis. They are a heterogeneous group of sporadic or inherited vascular disorders characterized by localized lesions of arteriovenous, capillary, or lymphatic origin. Vascular malformations that occur inside bone tissue are rare. Herein, we report loss-of-function mutations in ELMO2 (which translates extracellular signals into cellular movements) that are causative for autosomal-recessive intraosseous vascular malformation (VMOS) in five different families. Individuals with VMOS suffer from life-threatening progressive expansion of the jaw, craniofacial, and other intramembranous bones caused by malformed blood vessels that lack a mature vascular smooth muscle layer. Analysis of primary fibroblasts from an affected individual showed that absence of ELMO2 correlated with a significant downregulation of binding partner DOCK1, resulting in deficient RAC1-dependent cell migration. Unexpectedly, elmo2-knockout zebrafish appeared phenotypically normal, suggesting that there might be human-specific ELMO2 requirements in bone vasculature homeostasis or genetic compensation by related genes. Comparative phylogenetic analysis indicated that elmo2 originated upon the appearance of intramembranous bones and the jaw in ancestral vertebrates, implying that elmo2 might have been involved in the evolution of these novel traits. The present findings highlight the necessity of ELMO2 for maintaining vascular integrity, specifically in intramembranous bones.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Bone and Bones/blood supply , Cytoskeletal Proteins/genetics , Mutation/genetics , Signal Transduction/genetics , Vascular Malformations/genetics , rac1 GTP-Binding Protein/metabolism , Adaptor Proteins, Signal Transducing/deficiency , Adaptor Proteins, Signal Transducing/metabolism , Adult , Alleles , Animals , Cell Movement , Cytoskeletal Proteins/deficiency , Cytoskeletal Proteins/metabolism , Evolution, Molecular , Female , Homozygote , Humans , Male , Phenotype , Phylogeny , Species Specificity , Vascular Malformations/metabolism , Vascular Malformations/pathology , Zebrafish/genetics , Zebrafish/physiology , rac GTP-Binding Proteins/genetics
20.
Am J Hum Genet ; 99(3): 695-703, 2016 09 01.
Article in English | MEDLINE | ID: mdl-27545681

ABSTRACT

Via whole-exome sequencing, we identified rare autosomal-recessive variants in UBA5 in five children from four unrelated families affected with a similar pattern of severe intellectual deficiency, microcephaly, movement disorders, and/or early-onset intractable epilepsy. UBA5 encodes the E1-activating enzyme of ubiquitin-fold modifier 1 (UFM1), a recently identified ubiquitin-like protein. Biochemical studies of mutant UBA5 proteins and studies in fibroblasts from affected individuals revealed that UBA5 mutations impair the process of ufmylation, resulting in an abnormal endoplasmic reticulum structure. In Caenorhabditis elegans, knockout of uba-5 and of human orthologous genes in the UFM1 cascade alter cholinergic, but not glutamatergic, neurotransmission. In addition, uba5 silencing in zebrafish decreased motility while inducing abnormal movements suggestive of seizures. These clinical, biochemical, and experimental findings support our finding of UBA5 mutations as a pathophysiological cause for early-onset encephalopathies due to abnormal protein ufmylation.


Subject(s)
Alleles , Brain Diseases/genetics , Mutation/genetics , Proteins/metabolism , Ubiquitin-Activating Enzymes/genetics , Age of Onset , Animals , Brain Mapping , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/metabolism , Child , Child, Preschool , Cholinergic Neurons/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/pathology , Epilepsy/genetics , Exome/genetics , Female , Fibroblasts , Genes, Recessive/genetics , Humans , Intellectual Disability/genetics , Magnetic Resonance Imaging , Male , Microcephaly/genetics , Movement Disorders , Proteins/genetics , Synaptic Transmission/genetics , Ubiquitin/genetics , Ubiquitin/metabolism , Ubiquitin-Activating Enzymes/deficiency , Ubiquitin-Activating Enzymes/metabolism , Ubiquitins/genetics , Ubiquitins/metabolism , Zebrafish/genetics , Zebrafish Proteins/deficiency , Zebrafish Proteins/genetics , Zebrafish Proteins/metabolism
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