-
Nature Reviews. Disease Primers Sep 2019Fanconi anaemia (FA), ataxia telangiectasia (A-T), Nijmegen breakage syndrome (NBS) and Bloom syndrome (BS) are clinically distinct, chromosome instability (or breakage)... (Review)
Review
Fanconi anaemia (FA), ataxia telangiectasia (A-T), Nijmegen breakage syndrome (NBS) and Bloom syndrome (BS) are clinically distinct, chromosome instability (or breakage) disorders. Each disorder has its own pattern of chromosomal damage, with cells from these patients being hypersensitive to particular genotoxic drugs, indicating that the underlying defect in each case is likely to be different. In addition, each syndrome shows a predisposition to cancer. Study of the molecular and genetic basis of these disorders has revealed mechanisms of recognition and repair of DNA double-strand breaks, DNA interstrand crosslinks and DNA damage during DNA replication. Specialist clinics for each disorder have provided the concentration of expertise needed to tackle their characteristic clinical problems and improve outcomes. Although some treatments of the consequences of a disorder may be possible, for example, haematopoietic stem cell transplantation in FA and NBS, future early intervention to prevent complications of disease will depend on a greater understanding of the roles of the affected DNA repair pathways in development. An important realization has been the predisposition to cancer in carriers of some of these gene mutations.
Topics: Ataxia Telangiectasia; Bloom Syndrome; DNA Damage; DNA Repair-Deficiency Disorders; Fanconi Anemia; Humans; Nijmegen Breakage Syndrome
PubMed: 31537806
DOI: 10.1038/s41572-019-0113-0 -
CNS Drugs Sep 2023The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in the modulation of neuronal excitability, and a disruption of GABAergic... (Review)
Review
The inhibitory neurotransmitter γ-aminobutyric acid (GABA) plays an important role in the modulation of neuronal excitability, and a disruption of GABAergic transmission contributes to the pathogenesis of some seizure disorders. Although many currently available antiseizure medications do act at least in part by potentiating GABAergic transmission, there is an opportunity for further research aimed at developing more innovative GABA-targeting therapies. The present article summarises available evidence on a number of such treatments in clinical development. These can be broadly divided into three groups. The first group consists of positive allosteric modulators of GABA receptors and includes Staccato alprazolam (an already marketed benzodiazepine being repurposed in epilepsy as a potential rescue inhalation treatment for prolonged and repetitive seizures), the α2/3/5 subtype-selective agents darigabat and ENX-101, and the orally active neurosteroids ETX155 and LPCN 2101. A second group comprises two drugs already marketed for non-neurological indications, which could be repurposed as treatments for seizure disorders. These include bumetanide, a diuretic agent that has undergone clinical trials in phenobarbital-resistant neonatal seizures and for which the rationale for further development in this indication is under debate, and ivermectin, an antiparasitic drug currently investigated in a randomised double-blind trial in focal epilepsy. The last group comprises a series of highly innovative therapies, namely GABAergic interneurons (NRTX-001) delivered via stereotactic cerebral implantation as a treatment for mesial temporal lobe epilepsy, an antisense oligonucleotide (STK-001) aimed at upregulating NaV1.1 currents and restoring the function of GABAergic interneurons, currently tested in a trial in patients with Dravet syndrome, and an adenoviral vector-based gene therapy (ETX-101) scheduled for investigation in Dravet syndrome. Another agent, a subcutaneously administered neuroactive peptide (NRP2945) that reportedly upregulates the expression of GABA receptor α and β subunits is being investigated, with Lennox-Gastaut syndrome and other epilepsies as proposed indications. The diversity of the current pipeline underscores a strong interest in the GABA system as a target for new treatment development in epilepsy. To date, limited clinical data are available for these investigational treatments and further studies are required to assess their potential value in addressing unmet needs in epilepsy management.
Topics: Infant, Newborn; Humans; Epilepsy; gamma-Aminobutyric Acid; Epilepsies, Myoclonic; Epilepsies, Partial; Lennox Gastaut Syndrome; Randomized Controlled Trials as Topic
PubMed: 37603261
DOI: 10.1007/s40263-023-01025-4 -
Nature May 2022The global emergence of many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants jeopardizes the protective antiviral immunity induced after infection... (Review)
Review
The global emergence of many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants jeopardizes the protective antiviral immunity induced after infection or vaccination. To address the public health threat caused by the increasing SARS-CoV-2 genomic diversity, the National Institute of Allergy and Infectious Diseases within the National Institutes of Health established the SARS-CoV-2 Assessment of Viral Evolution (SAVE) programme. This effort was designed to provide a real-time risk assessment of SARS-CoV-2 variants that could potentially affect the transmission, virulence, and resistance to infection- and vaccine-induced immunity. The SAVE programme is a critical data-generating component of the US Government SARS-CoV-2 Interagency Group to assess implications of SARS-CoV-2 variants on diagnostics, vaccines and therapeutics, and for communicating public health risk. Here we describe the coordinated approach used to identify and curate data about emerging variants, their impact on immunity and effects on vaccine protection using animal models. We report the development of reagents, methodologies, models and notable findings facilitated by this collaborative approach and identify future challenges. This programme is a template for the response to rapidly evolving pathogens with pandemic potential by monitoring viral evolution in the human population to identify variants that could reduce the effectiveness of countermeasures.
Topics: Animals; Biological Evolution; COVID-19; COVID-19 Vaccines; Humans; National Institute of Allergy and Infectious Diseases (U.S.); Pandemics; Pharmacogenomic Variants; SARS-CoV-2; United States; Virulence
PubMed: 35361968
DOI: 10.1038/s41586-022-04690-5 -
Science (New York, N.Y.) Aug 2022To combat future severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and spillovers of SARS-like betacoronaviruses (sarbecoviruses) threatening global...
To combat future severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants and spillovers of SARS-like betacoronaviruses (sarbecoviruses) threatening global health, we designed mosaic nanoparticles that present randomly arranged sarbecovirus spike receptor-binding domains (RBDs) to elicit antibodies against epitopes that are conserved and relatively occluded rather than variable, immunodominant, and exposed. We compared immune responses elicited by mosaic-8 (SARS-CoV-2 and seven animal sarbecoviruses) and homotypic (only SARS-CoV-2) RBD nanoparticles in mice and macaques and observed stronger responses elicited by mosaic-8 to mismatched (not on nanoparticles) strains, including SARS-CoV and animal sarbecoviruses. Mosaic-8 immunization showed equivalent neutralization of SARS-CoV-2 variants, including Omicrons, and protected from SARS-CoV-2 and SARS-CoV challenges, whereas homotypic SARS-CoV-2 immunization protected only from SARS-CoV-2 challenge. Epitope mapping demonstrated increased targeting of conserved epitopes after mosaic-8 immunization. Together, these results suggest that mosaic-8 RBD nanoparticles could protect against SARS-CoV-2 variants and future sarbecovirus spillovers.
Topics: Animals; Antibodies, Neutralizing; Antibodies, Viral; Betacoronavirus; Coronavirus Infections; Disease Models, Animal; Epitopes; Macaca; Mice; Nanoparticles; Protein Domains; SARS-CoV-2; Spike Glycoprotein, Coronavirus; Zoonoses
PubMed: 35857620
DOI: 10.1126/science.abq0839 -
Blood Jan 2021There is growing evidence supporting an inherited basis for susceptibility to acute lymphoblastic leukemia (ALL) in children. In particular, we and others reported...
There is growing evidence supporting an inherited basis for susceptibility to acute lymphoblastic leukemia (ALL) in children. In particular, we and others reported recurrent germline ETV6 variants linked to ALL risk, which collectively represent a novel leukemia predisposition syndrome. To understand the influence of ETV6 variation on ALL pathogenesis, we comprehensively characterized a cohort of 32 childhood leukemia cases arising from this rare syndrome. Of 34 nonsynonymous germline ETV6 variants in ALL, we identified 22 variants with impaired transcription repressor activity, loss of DNA binding, and altered nuclear localization. Missense variants retained dimerization with wild-type ETV6 with potentially dominant-negative effects. Whole-transcriptome and whole-genome sequencing of this cohort of leukemia cases revealed a profound influence of germline ETV6 variants on leukemia transcriptional landscape, with distinct ALL subsets invoking unique patterns of somatic cooperating mutations. 70% of ALL cases with damaging germline ETV6 variants exhibited hyperdiploid karyotype with characteristic recurrent mutations in NRAS, KRAS, and PTPN11. In contrast, the remaining 30% cases had a diploid leukemia genome and an exceedingly high frequency of somatic copy-number loss of PAX5 and ETV6, with a gene expression pattern that strikingly mirrored that of ALL with somatic ETV6-RUNX1 fusion. Two ETV6 germline variants gave rise to both acute myeloid leukemia and ALL, with lineage-specific genetic lesions in the leukemia genomes. ETV6 variants compromise its tumor suppressor activity in vitro with specific molecular targets identified by assay for transposase-accessible chromatin sequencing profiling. ETV6-mediated ALL predisposition exemplifies the intricate interactions between inherited and acquired genomic variations in leukemia pathogenesis.
Topics: Cell Transformation, Neoplastic; Child; Genes, Dominant; Genetic Predisposition to Disease; Genome, Human; Germ-Line Mutation; Humans; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-ets; Repressor Proteins; ETS Translocation Variant 6 Protein
PubMed: 32693409
DOI: 10.1182/blood.2020006164 -
Frontiers in Neurology 2021Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS; the most common phenotype of corticobasal degeneration) are tauopathies with a relentless course,... (Review)
Review
Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS; the most common phenotype of corticobasal degeneration) are tauopathies with a relentless course, usually starting in the mid-60s and leading to death after an average of 7 years. There is as yet no specific or disease-modifying treatment. Clinical deficits in PSP are numerous, involve the entire neuraxis, and present as several discrete phenotypes. They center on rigidity, bradykinesia, postural instability, gait freezing, supranuclear ocular motor impairment, dysarthria, dysphagia, incontinence, sleep disorders, frontal cognitive dysfunction, and a variety of behavioral changes. CBS presents with prominent and usually asymmetric dystonia, apraxia, myoclonus, pyramidal signs, and cortical sensory loss. The symptoms and deficits of PSP and CBS are amenable to a variety of treatment strategies but most physicians, including many neurologists, are reluctant to care for patients with these conditions because of unfamiliarity with their multiplicity of interacting symptoms and deficits. CurePSP, the organization devoted to support, research, and education for PSP and CBS, created its CurePSP Centers of Care network in North America in 2017 to improve patient access to clinical expertise and develop collaborations. The directors of the 25 centers have created this consensus document outlining best practices in the management of PSP and CBS. They formed a writing committee for each of 12 sub-topics. A 4-member Steering Committee collated and edited the contributions. The result was returned to the entire cohort of authors for further comments, which were considered for incorporation by the Steering Committee. The authors hope that this publication will serve as a convenient guide for all clinicians caring for patients with PSP and CBS and that it will improve care for patients with these devastating but manageable disorders.
PubMed: 34276544
DOI: 10.3389/fneur.2021.694872 -
BMJ (Clinical Research Ed.) Sep 2021To establish if the use of early computed tomography (CT) coronary angiography improves one year clinical outcomes in patients presenting to the emergency department... (Randomized Controlled Trial)
Randomized Controlled Trial
OBJECTIVES
To establish if the use of early computed tomography (CT) coronary angiography improves one year clinical outcomes in patients presenting to the emergency department with acute chest pain and at intermediate risk of acute coronary syndrome and subsequent clinical events.
DESIGN
Randomised controlled trial.
SETTING
37 hospitals in the UK.
PARTICIPANTS
Adults with suspected or a provisional diagnosis of acute coronary syndrome and one or more of previous coronary heart disease, raised levels of cardiac troponin, or abnormal electrocardiogram.
INTERVENTIONS
Early CT coronary angiography and standard of care compared with standard of care only.
MAIN OUTCOME MEASURES
Primary endpoint was all cause death or subsequent type 1 or 4b myocardial infarction at one year.
RESULTS
Between 23 March 2015 and 27 June 2019, 1748 participants (mean age 62 years (standard deviation 13), 64% men, mean global registry of acute coronary events (GRACE) score 115 (standard deviation 35)) were randomised to receive early CT coronary angiography (n=877) or standard of care only (n=871). Median time from randomisation to CT coronary angiography was 4.2 (interquartile range 1.6-21.6) hours. The primary endpoint occurred in 51 (5.8%) participants randomised to CT coronary angiography and 53 (6.1%) participants who received standard of care only (adjusted hazard ratio 0.91 (95% confidence interval 0.62 to 1.35), P=0.65). Invasive coronary angiography was performed in 474 (54.0%) participants randomised to CT coronary angiography and 530 (60.8%) participants who received standard of care only (adjusted hazard ratio 0.81 (0.72 to 0.92), P=0.001). There were no overall differences in coronary revascularisation, use of drug treatment for acute coronary syndrome, or subsequent preventive treatments between the two groups. Early CT coronary angiography was associated with a slightly longer time in hospital (median increase 0.21 (95% confidence interval 0.05 to 0.40) days from a median hospital stay of 2.0 to 2.2 days).
CONCLUSIONS
In intermediate risk patients with acute chest pain and suspected acute coronary syndrome, early CT coronary angiography did not alter overall coronary therapeutic interventions or one year clinical outcomes, but reduced rates of invasive angiography while modestly increasing length of hospital stay. These findings do not support the routine use of early CT coronary angiography in intermediate risk patients with acute chest pain and suspected acute coronary syndrome.
TRIAL REGISTRATION
ISRCTN19102565, NCT02284191.
Topics: Acute Coronary Syndrome; Acute Disease; Aged; Chest Pain; Computed Tomography Angiography; Early Diagnosis; Emergency Service, Hospital; Female; Heart Disease Risk Factors; Humans; Length of Stay; Male; Middle Aged; Myocardial Infarction; Outcome Assessment, Health Care; Proportional Hazards Models; Risk Assessment; Standard of Care; Time Factors
PubMed: 34588162
DOI: 10.1136/bmj.n2106 -
The Journal of Clinical Investigation Dec 2022Axon loss contributes to many common neurodegenerative disorders. In healthy axons, the axon survival factor NMNAT2 inhibits SARM1, the central executioner of programmed...
Axon loss contributes to many common neurodegenerative disorders. In healthy axons, the axon survival factor NMNAT2 inhibits SARM1, the central executioner of programmed axon degeneration. We identified 2 rare NMNAT2 missense variants in 2 brothers afflicted with a progressive neuropathy syndrome. The polymorphisms resulted in amino acid substitutions V98M and R232Q, which reduced NMNAT2 NAD+-synthetase activity. We generated a mouse model to mirror the human syndrome and found that Nmnat2V98M/R232Q compound-heterozygous CRISPR mice survived to adulthood but developed progressive motor dysfunction, peripheral axon loss, and macrophage infiltration. These disease phenotypes were all SARM1-dependent. Remarkably, macrophage depletion therapy blocked and reversed neuropathic phenotypes in Nmnat2V98M/R232Q mice, identifying a SARM1-dependent neuroimmune mechanism as a key driver of disease pathogenesis. These findings demonstrate that SARM1 induced inflammatory neuropathy and highlight the potential of immune therapy as a treatment for this rare syndrome and other neurodegenerative conditions associated with NMNAT2 loss and SARM1 activation.
Topics: Male; Animals; Mice; Humans; Adult; Armadillo Domain Proteins; Nicotinamide-Nucleotide Adenylyltransferase; Nerve Degeneration; Cytoskeletal Proteins; Axons; Peripheral Nervous System Diseases; Macrophages
PubMed: 36287209
DOI: 10.1172/JCI159800