10 research outputs found
Stickler Syndrome: A Review of Clinical Manifestations and the Genetics Evaluation
Stickler Syndrome (SS) is a multisystem collagenopathy frequently encountered by ophthalmologists due to the high rate of ocular complications. Affected individuals are at significantly increased risk for retinal detachment and blindness, and early detection and diagnosis are critical in improving visual outcomes for these patients. Systemic findings are also common, with craniofacial, skeletal, and auditory systems often involved. SS is genotypically and phenotypically heterogenous, which can make recognizing and correctly diagnosing individuals difficult. Molecular genetic testing should be considered in all individuals with suspected SS, as diagnosis not only assists in treatment and management of the patient but may also help identify other at-risk family members. Here we review common clinical manifestation of SS and genetic tests frequently ordered as part of the SS evaluation
P473: Reconciling medical genetics educational competencies and closing gaps in undergraduate medical education*
Phenotypic Screening with Oleaginous Microalgae Reveals Modulators of Lipid Productivity
Here
we describe the first phenotypic screening with microalgae
to study lipid metabolism and to discover organic small molecules
as chemical triggers that increase growth and lipid production. A
microplate assay has been developed for analysis of intracellular
lipids using Nile Red fluorescence in order to screen a collection
of diverse bioactive organic molecules (e.g., kinase inhibitors) with
four strains of oleaginous microalgae (<i>Nannochloropsis salina</i>, <i>Nannochloropsis oculata</i>, <i>Nannochloris</i> sp., and <i>Phaeodactylum tricornutum</i>). Several small
molecules identified in microplate screening increased lipid productivity
>200% without decreasing growth and biomass production. Selected
compounds
were further investigated in the context of larger batch culture experiments
(e.g., 500 mL) and demonstrated to increase lipid levels (up to 84%)
while maintaining or increasing the specific growth rate. Bioactive
molecules such as forskolin and quinacrine were identified as promising
probes of microalgae lipid pathways. We have also determined that
common antioxidants such as epigallocatechin gallate and butylated
hydroxyanisole (BHA) increase lipid productivity and may represent
new probes of oxidative signaling pathways for photooxidative protection
Nanopore sequencing of influenza A and B in Oxfordshire and the United Kingdom, 2022-23
Objectives: We evaluated Nanopore sequencing for influenza surveillance.
Methods: Influenza A and B PCR-positive samples from hospital patients in Oxfordshire, UK, and a UK-wide population survey from winter 2022-23 underwent Nanopore sequencing following targeted rt-PCR amplification.
Results: From 941 infections, successful sequencing was achieved in 292/388(75%) available Oxfordshire samples: 231(79%) A/H3N2, 53(18%) A/H1N1, and 8(3%) B/Victoria and in 53/113(47%) UK-wide samples. Sequencing was more successful at lower Ct values. Most same-sample replicate sequences had identical haemagglutinin segments (124/141;88%); 36/39(92%) Illumina vs. Nanopore comparisons were identical, and 3(8%) differed by 1 variant.
Comparison of Oxfordshire and UK-wide sequences showed frequent inter-regional transmission. Infections were closely-related to 2022-23 vaccine strains. Only one sample had a neuraminidase inhibitor resistance mutation.
849/941(90%) Oxfordshire infections were community-acquired. 63/88(72%) potentially healthcare-associated cases shared a hospital ward with ≥1 known infectious case. 33 epidemiologically-plausible transmission links had sequencing data for both source and recipient: 8 were within ≤5 SNPs, of these, 5(63%) involved potential sources that were also hospital-acquired.
Conclusions: Nanopore influenza sequencing was reproducible and antiviral resistance rare. Inter-regional transmission was common; most infections were genomically similar. Hospital-acquired infections are likely an important source of nosocomial transmission and should be prioritised for infection prevention and control
Treatment of ARS deficiencies with specific amino acids
Purpose: Recessive cytosolic aminoacyl-tRNA synthetase (ARS) deficiencies are severe multiorgan diseases, with limited treatment options. By loading transfer RNAs (tRNAs) with their cognate amino acids, ARS are essential for protein translation. However, it remains unknown why ARS deficiencies lead to specific symptoms, especially early life and during infections. We set out to increase pathophysiological insight and improve therapeutic possibilities. Methods: In fibroblasts from patients with isoleucyl-RS (IARS), leucyl-RS (LARS), phenylalanyl-RS-beta-subunit (FARSB), and seryl-RS (SARS) deficiencies, we investigated aminoacylation activity, thermostability, and sensitivity to ARS-specific amino acid concentrations, and developed personalized treatments. Results: Aminoacylation activity was reduced in all patients, and further diminished at 38.5/40 °C (PLARS and PFARSB), consistent with infectious deteriorations. With lower cognate amino acid concentrations, patient fibroblast growth was severely affected. To prevent local and/or temporal deficiencies, we treated patients with corresponding amino acids (follow-up: 1/2–2 2/3rd years), and intensified treatment during infections. All patients showed beneficial treatment effects, most strikingly in growth (without tube feeding), head circumference, development, coping with infections, and oxygen dependency. Conclusion: For these four ARS deficiencies, we observed a common disease mechanism of episodic insufficient aminoacylation to meet translational demands and illustrate the power of amino acid supplementation for the expanding ARS patient group. Moreover, we provide a strategy for personalized preclinical functional evaluation
Treatment of ARS deficiencies with specific amino acids
Purpose: Recessive cytosolic aminoacyl-tRNA synthetase (ARS) deficiencies are severe multiorgan diseases, with limited treatment options. By loading transfer RNAs (tRNAs) with their cognate amino acids, ARS are essential for protein translation. However, it remains unknown why ARS deficiencies lead to specific symptoms, especially early life and during infections. We set out to increase pathophysiological insight and improve therapeutic possibilities. Methods: In fibroblasts from patients with isoleucyl-RS (IARS), leucyl-RS (LARS), phenylalanyl-RS-beta-subunit (FARSB), and seryl-RS (SARS) deficiencies, we investigated aminoacylation activity, thermostability, and sensitivity to ARS-specific amino acid concentrations, and developed personalized treatments. Results: Aminoacylation activity was reduced in all patients, and further diminished at 38.5/40 °C (PLARS and PFARSB), consistent with infectious deteriorations. With lower cognate amino acid concentrations, patient fibroblast growth was severely affected. To prevent local and/or temporal deficiencies, we treated patients with corresponding amino acids (follow-up: 1/2–2 2/3rd years), and intensified treatment during infections. All patients showed beneficial treatment effects, most strikingly in growth (without tube feeding), head circumference, development, coping with infections, and oxygen dependency. Conclusion: For these four ARS deficiencies, we observed a common disease mechanism of episodic insufficient aminoacylation to meet translational demands and illustrate the power of amino acid supplementation for the expanding ARS patient group. Moreover, we provide a strategy for personalized preclinical functional evaluation
JARID2 haploinsufficiency is associated with a clinically distinct neurodevelopmental syndrome
Purpose: JARID2, located on chromosome 6p22.3, is a regulator of histone methyltransferase complexes that is expressed in human neurons. So far, 13 individuals sharing clinical features including intellectual disability (ID) were reported with de novo heterozygous deletions in 6p22–p24 encompassing the full length JARID2 gene (OMIM 601594). However, all published individuals to date have a deletion of at least one other adjoining gene, making it difficult to determine if JARID2 is the critical gene responsible for the shared features. We aim to confirm JARID2 as a human disease gene and further elucidate the associated clinical phenotype. Methods: Chromosome microarray analysis, exome sequencing, and an online matching platform (GeneMatcher) were used to identify individuals with single-nucleotide variants or deletions involving JARID2. Results: We report 16 individuals in 15 families with a deletion or single-nucleotide variant in JARID2. Several of these variants are likely to result in haploinsufficiency due to nonsense-mediated messenger RNA (mRNA) decay. All individuals have developmental delay and/or ID and share some overlapping clinical characteristics such as facial features with those who have larger deletions involving JARID2. Conclusion: We report that JARID2 haploinsufficiency leads to a clinically distinct neurodevelopmental syndrome, thus establishing gene–disease validity for the purpose of diagnostic reporting
JARID2 haploinsufficiency is associated with a clinically distinct neurodevelopmental syndrome
Purpose: JARID2, located on chromosome 6p22.3, is a regulator of histone methyltransferase complexes that is expressed in human neurons. So far, 13 individuals sharing clinical features including intellectual disability (ID) were reported with de novo heterozygous deletions in 6p22–p24 encompassing the full length JARID2 gene (OMIM 601594). However, all published individuals to date have a deletion of at least one other adjoining gene, making it difficult to determine if JARID2 is the critical gene responsible for the shared features. We aim to confirm JARID2 as a human disease gene and further elucidate the associated clinical phenotype. Methods: Chromosome microarray analysis, exome sequencing, and an online matching platform (GeneMatcher) were used to identify individuals with single-nucleotide variants or deletions involving JARID2. Results: We report 16 individuals in 15 families with a deletion or single-nucleotide variant in JARID2. Several of these variants are likely to result in haploinsufficiency due to nonsense-mediated messenger RNA (mRNA) decay. All individuals have developmental delay and/or ID and share some overlapping clinical characteristics such as facial features with those who have larger deletions involving JARID2. Conclusion: We report that JARID2 haploinsufficiency leads to a clinically distinct neurodevelopmental syndrome, thus establishing gene–disease validity for the purpose of diagnostic reporting
Microenvironmental Modulation of Calcium Wave Propagation Velocity in Engineered Cardiac Tissues
Sex-specific cardiovascular comorbidities with associations in dermatologic and rheumatic disorders
Cardiology, dermatology, and rheumatology form a fascinating triad. Many skin and joint disorders are associated with cardiovascular comorbidities because they share etiologic elements. Female predominance is often remarkable and likely related to autoimmune pathology. Although studies have shown that X-encoded genes may be involved in the differences in immunity between males and females, other studies have also shown that sex chromosomes are irrelevant and that estrogens and androgens are responsible for the differences. The elevated immune activity in females provides a beneficial position in coping with a pathogenic stimulus but may also enhance their susceptibility to autoimmunity. The complexity of the immune system and its role as a defensive force against infection requires an armamentarium to precisely identify and selectively control inflammatory processes or cells which promote atherosclerosis. On the other hand, the inflammation in skin diseases seems to be an active source of diverse proinflammatory cytokines and chemokines which can predispose to cardiovascular comorbidities. Also, it has been shown that comorbidity disproportionately accelerates risk in women. The skin offers a readily available window to facilitate detection of risk factors or even to assist the diagnostic process regarding a variety of disorders, including those with cardiovascular involvement. Current imaging techniques provide exquisite capabilities for diagnosing and possibly even counteracting atherosclerotic plaque formation, before serious cardiovascular events occur. Combining imaging approaches (such as videocapillaroscopy, intravascular ultrasound, and FDG positron emission tomography) with insights based on immunology will likely accelerate advances in this area. We review major dermatologic manifestations and rheumatologic disorders which are associated with cardiac and vascular abnormalities. In particular we discuss sex-specific aspects concerning incidence and severity of cardiovascular disease associated with systemic sclerosis, rheumatoid arthritis, systemic lupus erythematosus, psoriasis, atopic dermatitis, and hidradenitis suppurativa