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Pathogenic variants in the leucine zipper-like transcriptional regulator 1 gene ( LZTR1 ) have been identified in schwannomatosis and Noonan syndrome. Here, we expand the phenotype spectrum of LZTR1 variants. We identified four loss-of-function heterozygous LZTR1 variants in five children with multiple café au lait macules and one adult with multiple café au lait macules and axillar freckling, by applying gene panel analysis in four families. The three LZTR1 variants, namely, c.184del/p.Glu62Ser fs *39, c.1927C < T/p.Gln643*, and c.857&#95;858delinsT/p.Gly286Val fs *65, were novel, whereas the variant c.1018C > T/ p.Arg340* had been previously reported in a patient with schwannomatosis. Similar to what is known from other LZTR1 -associated conditions, penetrance of the skin manifestations was reduced in two carriers of the familial variants. Our study expands the LZTR1 phenotype to the presence of isolated café au lait macules with or without freckling. Thus, variants in the LZTR1 gene should be considered in patients with multiple café au lait macules., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Horn, Neuhann, Hennig, Abad-Perez, Prott, Cardellini, Potratz, Leubner, Eichhorn, Merkel, Abicht and Kaindl.)

Background: Neurofibromatosis type 1, NF2 -related schwannomatosis and non- NF2 -related schwannomatosis (grouped under the abbreviation "NF") are rare hereditary tumor predisposition syndromes. Due to the low prevalence, variability in the range, and severity of manifestations, as well as limited treatment options, these conditions require innovative trial designs to accelerate the development of new treatments., Methods: Within European Patient-Centric Clinical Trial Platforms (EU-PEARL), we designed 2 platform-basket trials in NF. The trials were designed by a team of multidisciplinary NF experts and trial methodology experts., Results: The trial will consist of an observational and a treatment period. The observational period will serve as a longitudinal natural history study. The platform trial design and randomization to a sequence of available interventions allow for the addition of interventions during the trial. If a drug does not meet the predetermined efficacy endpoint or reveals unacceptable toxicities, participants may stop treatment on that arm and re-enter the observational period, where they can be re-randomized to a different treatment arm if eligible. Intervention-specific eligibility criteria and endpoints are listed in intervention-specific-appendices, allowing the flexibility and adaptability needed for highly variable and rare conditions like NF., Conclusions: These innovative platform-basket trials for NF may serve as a model for other rare diseases, as they will enhance the chance of identifying beneficial treatments through optimal learning from a small number of patients. The goal of these trials is to identify beneficial treatments for NF more rapidly and at a lower cost than traditional, single-agent clinical trials., Competing Interests: AAA participates in the advisory board of Alexion/AstraZeneca, and has received scientific support and speaker honoraria from the same company. AB declares no conflict of interest. JOB participates in the advisory board of SpringWorks Therapeutics. CC and BD report grants from EU-PEARL, the innovative Medicines Initiative 2 Joint Undertaking under grant agreement no 853966. PHD participates in the advisory board of Alexion/AstraZeneca and is the ICI of the SPRINKLE study sponsored by Alexion. AG reports no conflict of interest. DGE reports personal fees from AstraZeneca and personal fees from SpringWorks Therapeutics. MJF participates in advisory boards of Alexion/AstraZeneca, SpringWorks Therapeutics and DayOne, and has received research support from Alexion/AstraZeneca, Array Biopharma/Pfizer and Exelixis. REF reports grants and personal fees from AstraZeneca. GH is an employee of Novartis Pharma AG. UI is an employee of SpringWorks Therapeutics. GK is an employee of AstraZeneca. AK reports no conflict of interest. EL reports personal fees from AstraZeneca, personal fees from SpringWorks Therapeutics, and grants from EU-PEARL, the innovative Medicines Initiative 2 Joint Undertaking under grant agreement no 853966. JL declares no conflict of interest. MN declares no conflict of interest. RO reports grants from EU-PEARL, the innovative Medicines Initiative 2 Joint Undertaking under grant agreement no 853966 and has performed unpaid advisory work for Alexion. CP reports no conflict of interest. SP reports being a cofounder of NFlection Therapeutics and NF2 Therapeutics and served as a consultant for Akouos. TP reports no conflict of interest. BCW reports no conflict of interest. PW reports no conflict of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Society for Neuro-Oncology and the European Association of Neuro-Oncology.)

Advice from multiple stakeholders is required to design the optimal pediatric clinical trial. We present recommendations for acquiring advice from trial experts and patients/caregivers, derived from advice meetings that were performed through a collaboration of the Collaborative Network for European Clinical Trials for Children (c4c) and the European Patient-CEntric ClinicAl TRial PLatforms (EU-PEARL). Three advice meetings were performed: (1) an advice meeting for clinical and methodology experts, (2) an advice meeting for patients/caregivers, and (3) a combined meeting with both experts and patients/caregivers. Trial experts were recruited from c4c database. Patients/caregivers were recruited through a patient organization. Participants were asked to provide input on a trial protocol, including endpoints, outcomes, and the assessment schedule. Ten experts, 10 patients, and 13 caregivers participated. The advice meetings resulted in modification of eligibility criteria and outcome measures. We have provided recommendations for the most effective meeting type per protocol topic. Topics with limited options for patient input were most efficiently discussed in expert advice meetings. Other topics benefit from patient/caregiver input, either through a combined meeting with experts or a patients/caregivers-only advice meeting. Some topics, such as endpoints and outcome measures, are suitable for all meeting types. Combined sessions profit from synergy between experts and patients/caregivers, balancing input on protocol scientific feasibility and acceptability. Both experts and patients/caregivers provided critical input on the presented protocol. The combined meeting was the most effective methodology for most protocol topics. The presented methodology can be used effectively to acquire expert and patient feedback., (© 2023 The Authors. Clinical and Translational Science published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.)

Thousands of genetic variants in protein-coding genes have been linked to disease. However, the functional impact of most variants is unknown as they occur within intrinsically disordered protein regions that have poorly defined functions 1-3 . Intrinsically disordered regions can mediate phase separation and the formation of biomolecular condensates, such as the nucleolus 4,5 . This suggests that mutations in disordered proteins may alter condensate properties and function 6-8 . Here we show that a subset of disease-associated variants in disordered regions alter phase separation, cause mispartitioning into the nucleolus and disrupt nucleolar function. We discover de novo frameshift variants in HMGB1 that cause brachyphalangy, polydactyly and tibial aplasia syndrome, a rare complex malformation syndrome. The frameshifts replace the intrinsically disordered acidic tail of HMGB1 with an arginine-rich basic tail. The mutant tail alters HMGB1 phase separation, enhances its partitioning into the nucleolus and causes nucleolar dysfunction. We built a catalogue of more than 200,000 variants in disordered carboxy-terminal tails and identified more than 600 frameshifts that create arginine-rich basic tails in transcription factors and other proteins. For 12 out of the 13 disease-associated variants tested, the mutation enhanced partitioning into the nucleolus, and several variants altered rRNA biogenesis. These data identify the cause of a rare complex syndrome and suggest that a large number of genetic variants may dysregulate nucleoli and other biomolecular condensates in humans., (© 2023. The Author(s).)

Background and Objectives: Time spent in the electronic health record (EHR), away from direct patient care, is associated with physician burnout. Yet there is a lack of evidence quantifying EHR use among family physicians. The purpose of the study was to describe a method for quantifying habits and duration of use within the electronic health record in family medicine residents and faculty with particular attention paid to time spent after hours., Methods: We audited EHR time for family medicine residents and faculty using an EHR vendor-provided, web-based tracking system. We collected and analyzed the number of patient encounters, total time in the EHR per patient, total time in the EHR after hours by physicians for a 6-month time period., Results: Over the 6-month period reviewed, family medicine trainees and faculty saw between one and 164 patients monthly, spent between 17 and 217 minutes in the EHR per patient, and spent between 0 and 33 hours in the EHR after hours per month., Conclusions: Family medicine residents spend a significant amount of time completing EHR tasks after hours. Objective EHR data can be used by family medicine residency programs to devise interventions to decrease inefficient use of the EHR, decrease after-hours EHR use, and improve well-being.

Objective: Maternal autoantibodies are a risk factor for impaired brain development in offspring. Antibodies (ABs) against the NR1 (GluN1) subunit of the N-methyl-d-aspartate receptor (NMDAR) are among the most frequently diagnosed anti-neuronal surface ABs, yet little is known about effects on fetal development during pregnancy., Methods: We established a murine model of in utero exposure to human recombinant NR1 and isotype-matched nonreactive control ABs. Pregnant C57BL/6J mice were intraperitoneally injected on embryonic days 13 and 17 each with 240μg of human monoclonal ABs. Offspring were investigated for acute and chronic effects on NMDAR function, brain development, and behavior., Results: Transferred NR1 ABs enriched in the fetus and bound to synaptic structures in the fetal brain. Density of NMDAR was considerably reduced (up to -49.2%) and electrophysiological properties were altered, reflected by decreased amplitudes of spontaneous excitatory postsynaptic currents in young neonates (-34.4%). NR1 AB-treated animals displayed increased early postnatal mortality (+27.2%), impaired neurodevelopmental reflexes, altered blood pH, and reduced bodyweight. During adolescence and adulthood, animals showed hyperactivity (+27.8% median activity over 14 days), lower anxiety, and impaired sensorimotor gating. NR1 ABs caused long-lasting neuropathological effects also in aged mice (10 months), such as reduced volumes of cerebellum, midbrain, and brainstem., Interpretation: The data collectively support a model in which asymptomatic mothers can harbor low-level pathogenic human NR1 ABs that are diaplacentally transferred, causing neurotoxic effects on neonatal development. Thus, AB-mediated network changes may represent a potentially treatable neurodevelopmental congenital brain disorder contributing to lifelong neuropsychiatric morbidity in affected children. ANN NEUROL 2019;86:656-670., (© 2019 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is the most common autoimmune encephalitis related to autoantibody-mediated synaptic dysfunction. Cerebrospinal fluid-derived human monoclonal NR1 autoantibodies showed low numbers of somatic hypermutations or were unmutated. These unexpected germline-configured antibodies showed weaker binding to the NMDAR than matured antibodies from the same patient. In primary hippocampal neurons, germline NR1 autoantibodies strongly and specifically reduced total and synaptic NMDAR currents in a dose- and time-dependent manner. The findings suggest that functional NMDAR antibodies are part of the human naïve B cell repertoire. Given their effects on synaptic function, they might contribute to a broad spectrum of neuropsychiatric symptoms. Ann Neurol 2019;85:771-776., (© 2019 The Authors. Annals of Neurology published by Wiley Periodicals, Inc. on behalf of American Neurological Association.)

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a common autoimmune encephalitis presenting with psychosis, dyskinesias, autonomic dysfunction and seizures. The underlying autoantibodies against the NR1 subunit are directly pathogenic by disrupting synaptic NMDAR currents. However, antibody titers correlate only partially with the clinical outcome, suggesting the relevance of other factors such as antibody affinity. We thus determined the binding curves of human monoclonal autoantibodies and patients' cerebrospinal fluid (CSF) against NR1-expressing HEK293 cells using flow cytometry. Antibody affinity was highly variable with binding constants (half-maximal concentration, c 50 ) ranging from 1 to 74 µg/ml for monoclonal antibodies. Comparing values of individual monoclonal antibodies with human CSF samples suggested that the CSF signal is predominantly represented by higher-affinity antibodies, potentially in a concentration range of NR1 antibodies between 0.1 and 5 µg/ml, roughly reflecting 1-10% of total CSF IgG in NMDAR encephalitis. Binding curves further depended on the CSF composition which must be considered when interpreting established clinical routine assays. Normalization of measurements using reference samples allowed high reproducibility. Accurate and reproducible measurement of NR1 antibody binding suggested that biophysical properties of the antibody might contribute to disease severity. Normalization of the data can be an elegant way to allow comparable inter-laboratory quantification of CSF NR1 antibody titers in autoimmune encephalitis patients, a prerequisite for use as surrogate markers in clinical trials. Based on our calculations, low-affinity antibodies can easily remain undetected in routine cell-based assays, indicating that their relation to clinical symptoms should be analyzed in future studies.

SEE ZEKERIDOU AND LENNON DOI101093/AWW213 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a recently discovered autoimmune syndrome associated with psychosis, dyskinesias, and seizures. Little is known about the cerebrospinal fluid autoantibody repertoire. Antibodies against the NR1 subunit of the NMDAR are thought to be pathogenic; however, direct proof is lacking as previous experiments could not distinguish the contribution of further anti-neuronal antibodies. Using single cell cloning of full-length immunoglobulin heavy and light chain genes, we generated a panel of recombinant monoclonal NR1 antibodies from cerebrospinal fluid memory B cells and antibody secreting cells of NMDAR encephalitis patients. Cells typically carried somatically mutated immunoglobulin genes and had undergone class-switching to immunoglobulin G, clonally expanded cells carried identical somatic hypermutation patterns. A fraction of NR1 antibodies were non-mutated, thus resembling 'naturally occurring antibodies' and indicating that tolerance induction against NMDAR was incomplete and somatic hypermutation not essential for functional antibodies. However, only a small percentage of cerebrospinal fluid-derived antibodies reacted against NR1. Instead, nearly all further antibodies bound specifically to diverse brain-expressed epitopes including neuronal surfaces, suggesting that a broad repertoire of antibody-secreting cells enrich in the central nervous system during encephalitis. Our functional data using primary hippocampal neurons indicate that human cerebrospinal fluid-derived monoclonal NR1 antibodies alone are sufficient to cause neuronal surface receptor downregulation and subsequent impairment of NMDAR-mediated currents, thus providing ultimate proof of antibody pathogenicity. The observed formation of immunological memory might be relevant for clinical relapses., (© The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Background: The analysis of cerebrospinal fluid (CSF) is usually done under steady-state conditions, when proteins (e.g., immunoglobulins) reach diffusion equilibrium between blood and CSF. However, little data has been published on CSF analysis under non-steady-state conditions after therapeutic apheresis. By reducing serum proteins (e.g., immunoglobulins), while leaving CSF unchanged, therapeutic apheresis might cause spuriously altered intrathecal immunoglobulin fractions., Methods: Based on the incidental finding of plasma exchange-induced increased intrathecal immunoglobulin fractions in a cohort of 12 unsystematically selected patients with various neurological disorders, we retrospectively investigated CSF results that had been raised during routine diagnostic work-up from 41 consecutive neurological patients (predominantly Guillain-Barré syndrome and autoimmune encephalitis) treated with plasmapheresis or immunoadsorption in a tertiary care university hospital in whom lumbar puncture (LP) was performed after a varying number of treatments of therapeutic apheresis., Results: Only when LP was performed 1 day after therapeutic apheresis, spurious quantitative intrathecal immunoglobulin (Ig) synthesis of at least one subclass (IgG, IgA and/or IgM) was found in 68.4 % of the patients, irrespective of the number of treatments, in all age groups and independent of other previous immunotherapies (e.g., steroids). This phenomenon occurred only transiently and was almost always accompanied by an elevation of the IgG index. In one patient, an elevated IgG index was noticed even 2 days after plasmapheresis. Neither quantitative Ig synthesis, nor elevated IgG index was observed when the LP was performed three or more days after therapeutic apheresis., Conclusions: Spurious quantitative intrathecal Ig synthesis and increased IgG index are common findings shortly after plasmapheresis or immunoadsorption due to altered serum immunoglobulin levels. Knowledge of this phenomenon is needed for clinicians to prevent false interpretations leading to unnecessary diagnostic and therapeutic procedures. Misdiagnoses can be avoided by considering the characteristic CSF constellation including absence of oligoclonal bands and the close temporal relation to therapeutic apheresis.

Introduction. Men with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency show impaired fecundity due to testicular adrenal rest tumors and/or suppression of the gonadal axis. Sexual well-being might be an additional factor; however, no data exists. Patients and Methods. Prospective longitudinal monocentric study included 20 male CAH patients (14 salt wasting, 6 simple virilizing; age 18-49 yr). Clinical assessment, testicular ultrasound, biochemical and hormonal parameters, three validated self-assessment questionnaires (SF-36, GBB-24, and HADS), and male Brief Sexual Function Inventory (BSFI) were analyzed at baseline and after two years. Results. Basal LH and testosterone levels suggested normal testicular function. LH and FSH responses to GnRH were more pronounced in patients with a good therapy control according to androstenedione/testosterone ratio < 0.2. This group had significant higher percentage of patients on dexamethasone medication. GBB-24, HADS, and SF-36 showed impaired z-scores and no changes at follow-up. BSFI revealed impairments in dimensions "sexual drive," "erections," and "ejaculations," whereas "problem assessment" and "overall satisfaction" revealed normal z-scores. Androstenedione levels correlated (P = 0.036) inversely with z-scores for "sexual drive" with higher levels associated with impaired "sexual drive." Conclusion. Male CAH patients showed a partly impaired sexual well-being which might be an additional factor for reduced fecundity.