Neural crest lineage in the protovertebrate model Ciona.

Neural crest cells are multipotent progenitors that produce defining features of vertebrates such as the 'new head'1. Here we use the tunicate, Ciona, to explore the evolutionary origins of neural crest since this invertebrate chordate is among the closest living relatives of vertebrates2-4. Previous studies identified two potential neural crest cell types in Ciona, sensory pigment cells and bipolar tail neurons5,6. Recent findings suggest that  bipolar tail neurons are homologous to cranial sensory ganglia rather than derivatives of neural crest7,8. Here we show that the pigment cell lineage also produces neural progenitor cells that form regions of the juvenile nervous system following metamorphosis. Neural progenitors are also a major derivative of neural crest in vertebrates, suggesting that the last common ancestor of tunicates and vertebrates contained a multipotent progenitor population at the neural plate border. It would therefore appear that a key property of neural crest, multipotentiality, preceded the emergence of vertebrates.

Corticostriatal Maldevelopment in the R6/2 Mouse Model of Juvenile Huntington's Disease.

There is a growing consensus that brain development in Huntington's disease (HD) is abnormal, leading to the idea that HD is not only a neurodegenerative but also a neurodevelopmental disorder. Indeed, structural and functional abnormalities have been observed during brain development in both humans and animal models of HD. However, a concurrent study of cortical and striatal development in a genetic model of HD is still lacking. Here we report significant alterations of corticostriatal development in the R6/2 mouse model of juvenile HD. We examined wildtype (WT) and R6/2 mice at postnatal (P) days 7, 14, and 21. Morphological examination demonstrated early structural and cellular alterations reminiscent of malformations of cortical development, and ex vivo electrophysiological recordings of cortical pyramidal neurons (CPNs) demonstrated significant age- and genotype-dependent changes of intrinsic membrane and synaptic properties. In general, R6/2 CPNs had reduced cell membrane capacitance and increased input resistance (P7 and P14), along with reduced frequency of spontaneous excitatory and inhibitory synaptic events during early development (P7), suggesting delayed cortical maturation. This was confirmed by increased occurrence of GABA A receptor-mediated giant depolarizing potentials at P7. At P14, the rheobase of CPNs was significantly reduced, along with increased excitability. Altered membrane and synaptic properties of R6/2 CPNs recovered progressively, and by P21 they were similar to WT CPNs. In striatal medium-sized spiny neurons (MSNs), a different picture emerged. Intrinsic membrane properties were relatively normal throughout development, except for a transient increase in membrane capacitance at P14. The first alterations in MSNs synaptic activity were observed at P14 and consisted of significant deficits in GABAergic inputs, however, these also were normalized by P21. In contrast, excitatory inputs began to decrease at this age. We conclude that the developing HD brain is capable of compensating for early developmental abnormalities and that cortical alterations precede and are a main contributor of striatal changes. Addressing cortical maldevelopment could help prevent or delay disease manifestations.

Future directions for equity-centered body image and eating disorders prevention work.

This article concludes the special issue, Identifying and Closing the Gaps in the Prevention of Disordered Eating and Eating Disorders, by reflecting on some of the shared themes as the bases for guiding improvements, if not innovations, in future research. Overall, the articles in this collection highlight the progress achieved within eating disorders prevention in recent years, while addressing many of the existing-and sometimes glaring-gaps within the field. While these manuscripts represent important steps forward, they also offer conceptual frameworks and methodological roadmaps for future developments in the field. Based on prominent themes across those 12 articles, in this conclusion we recommend that future research within eating disorders prevention prioritize equity within research teams, participants, and research approaches. We encourage partnerships with non-academic teams and communities, as well as with multidisciplinary academic colleagues, to ensure that foundational research is directly translatable into program development and implementation, that our prevention efforts are sustainable over time, and that our research development and participating "audiences" include perspectives currently underrepresented in the literature. We also encourage action-based research in which research teams and other stakeholders consider ways to address policy and other systemic factors that lead to body- and appearance-based oppression and inequality.

Prevalence and predictors of HIV among patients presenting to US emergency departments with opioid overdose.

INTRODUCTION: Opioid overdose deaths in the U.S. have risen dramatically in the past decade, largely due to the surge in illicitly manufactured fentanyl. Injection drug use is a known risk factor for HIV, further complicating the long-term consequences of opioid use. The baseline prevalence of HIV among adults in the US is 0.46 %. The primary purpose of this study was to determine the prevalence and risk factors of HIV among patients presenting to the emergency departments (ED) with an acute opioid overdose. METHODS: This study is a prospective observational cohort study from the ToxIC Fentalog Study group. Patients age 18 years of age or older are included if they present to one of 10 participating U.S. hospitals in 9 states between September 2020 and May 2023 with a suspected opioid overdose and had waste serum available after routine laboratory testing. Clinical data is collected from the medical record and patient serum is sent for comprehensive toxicologic analysis via liquid chromatography quadrupole time-of-flight mass spectroscopy to detect the presence of over 1200 substances including illicit opioids, novel synthetic opioids, medications, and adulterants. Logistic multivariable regression was performed to examine the association between demographic, behavioral, and serum toxicology data with risk factors and HIV status. RESULTS: Among the total cohort (n=1690), 1062 cases had known HIV status (62.8 % of total sample). Among patients with a known HIV status, 60 (5.6 % [95 % CI: 4.2 %, 7.0 %]) were HIV positive. Patients with HIV reported stimulant use more frequently (13.3 %) than those without HIV (6.8 %; p=0.003). After controlling for confounding, bipolar psychiatric history was a significant independent predictor of HIV positivity (aOR: 1.08; 95 % CI: 1.02, 1.13) in this population. CONCLUSIONS: In this large multicenter cohort, the prevalence of HIV for ED patients with illicit opioid overdose was 9 times higher than that expected by the general population. Bipolar disorder appears to be a novel risk factor for HIV positivity in this patient population.

Clinical Efficacy of Zoledronic Acid on Fracture Reduction in Youth with Primary and Secondary Skeletal Fragility.

CONTEXT: Prior studies have demonstrated the safety and efficacy of zoledronic acid (ZA) to increase bone mineral density (BMD) in children. By contrast, the efficacy of ZA on fractures in the pediatric population remains uncertain. OBJECTIVE: To investigate the effect of ZA on fracture rate in a clinical cohort of children and young adults with skeletal fragility. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENTS: 102 individuals (65 males; 39 with primary and 63 with secondary skeletal fragility) ages 0-21 years old treated with ZA for skeletal fragility between 2010 and 2017. INTERVENTION: ZA was prescribed at discretion of the treating clinician using a standardized protocol. MAIN OUTCOME MEASURES: The primary outcome was change in annualized fracture rate. Secondary outcomes included long bone and spine fracture rates. Areal BMD was analyzed in a subset of individuals with dual energy X-ray absorptiometry (DXA) scans. RESULTS: The overall median fracture rate decreased from 0.6 (IQR: 0.3-1.1) to 0 (IQR: 0-0.4) fractures per year, p<0.001, over a median treatment duration of 1.8 (IQR:0.6-3.0) years. Significant reductions in fracture rate were observed in both primary [1.0 (IQR: 0.6-1.5) to 0.3 (IQR: 0-0.6)] and secondary [0.5 (IQR: 0.1-0.8) to 0 (IQR: 0-0.3)] forms of skeletal fragility, p<0.001 for both. Significant reductions in fracture rate persisted when limited to long bone or long bone plus spine fractures. CONCLUSION: ZA treatment as a component of clinical care was associated with significant declines in fracture rate in this cohort of children and young adults with skeletal fragility.

Heroin or fentanyl: Prevalence of confirmed fentanyl in ED patients with suspected heroin overdose.

Background: United States drug overdose deaths are being driven by the increasing prevalence of fentanyl, but whether patients are knowingly using fentanyl is unclear. We examined the analytical confirmation of fentanyl in emergency department (ED) patients with documented heroin overdose. Hypothesis: We hypothesized that the proportion of fentanyl and fentanyl analogs would be higher than that of confirmed heroin. Methods: This is a subgroup analysis from a prospective multicenter consecutive cohort of ED patients age 18+ with opioid overdose presenting to 10 US sites within the Toxicology Investigators Consortium from 2020 to 2021. Toxicology analysis was performed using liquid chromatography quadrupole time-of-flight mass spectrometry. De-identified toxicology results were paired with the clinical database. The primary outcome was the proportion of patients with fentanyl analytes detected in their serum. Results: Of 1006 patients screened, 406 were eligible, and of 168 patients who reported that they had taken heroin or had a documented heroin overdose, 88% (n = 147) were in fact found to have fentanyl and/or a fentanyl analog present on serum analysis (p < 0.0001). In contrast, only 46 of the 168 patients with reported or documented heroin overdose (27%) were found to have heroin biomarkers present. Conclusion: The prevalence of confirmed fentanyl in ED patients with suspected heroin overdose was extremely high, while the prevalence of heroin was very low. There was a high degree of mismatch between the opioids believed to be the overdose agent versus the actual opioids identified on serum toxicology. Clinicians in the United States should presume that fentanyl is involved in all illicit opioid overdoses and should counsel patients on harm reduction measures.

Autism Symptom Presentation and Hierarchical Models of Intelligence.

BACKGROUND: There is a substantial history studying the relationship between general intelligence and the core symptoms of autism. However, a gap in knowledge is how dimensional autism symptomatology associates with different components of clinically-relevant hierarchical models of intelligence. METHOD: We examined correlations between autism diagnostic symptom magnitude (Autism Diagnostic Observational Schedule; ADOS) and a hierarchical statistical model of intelligence. One autistic cohort was tested on the fourth edition of Wechsler Intelligence Scale for Children (WISC-IV; N = 131), and another on the fifth edition (WISC-V; N = 83). We anticipated a convergent pattern of results between cohorts. RESULTS: On WISC-IV, ADOS scores were correlated significantly with g and three out of four intermediate factor scores, which was a broader pattern of correlations than anticipated from the literature. In the WISC-V cohort, only one intermediate factor correlated significantly with the ADOS; correlations with g and the other intermediate factors were less statistically certain. ADOS-factor correlations were larger in the WISC-IV than WISC-V cohort; this difference was significant at the 90% level. CONCLUSIONS: WISC-IV shows dimensional relationships with ADOS at multiple points in the hierarchical model of intelligence. Moreover, the current results provide evidence that relationship between core autism symptomatology and the construct of general intelligence may depend on how intelligence is measured. Known cohort effects in the relationship between categorical autism diagnosis and general intelligence have previously been attributed to changes in autism diagnostic practices. To our knowledge, this is the first evidence that differing versions of IQ tests may be implicated.

Understanding how cells and organisms keep time during development.

A classical question in biology is how different processes are controlled in space and time, with research pointing to different mechanisms as timers. In this collection of Voices, we asked researchers to define their scientific questions related to time-keeping and the approaches they use to answer them.

Circulating MicroRNA as a Potential Biomarker for Skeletal Disease in Primary Hyperparathyroidism: A Case-control Study.

OBJECTIVE: The goal of this study was to characterize the microRNA (miRNA) expression signatures in patients with Primary hyperparathyroidism (PHPT) and identify miRNA biomarkers of bone homeostasis. BACKGROUND: PHPT is associated with increased bone turnover and decreased bone mass. miRNA are markers of bone remodeling. METHODS: We performed a prospective case-control study of postmenopausal females with PHPT and control subjects matched for race, age, and bone mineral density (BMD). We collected clinical and biochemical data, assessed BMD by dual-energy x-ray absorptiometry, and measured 27 serum miRNAs related to bone remodeling. We used linear regression to assess the correlation between miRNA levels, conventional biochemical markers, and BMD. RESULTS: A total of 135 subjects were evaluated, including 49 with PHPT (discovery group), 47 control patients without PHPT, and an independent validation cohort of 39 PHPT patients. Of 27 miRNAs evaluated, 9 (miR-335-5p, miR-130b-3p, miR-125b-5p, miR-23a-3p, miR-152-3p, miR-582-5p, miR-144-5p, miR-320a, and miR-19b-3p) were differentially expressed in PHPT compared with matched control subjects. All 9 differentially expressed miRNAs significantly correlated with levels of serum parathyroid hormone (PTH), and 8 of the 9 correlated with calcium levels. No differentially expressed miRNAs were consistently correlated with markers of BMD. Subjects with PHPT segregate from controls based on the signature of these 9 miRNAs on principle component analysis. CONCLUSIONS: These data suggest that PHPT is characterized by a unique miRNA signature that is distinct from postmenopausal and idiopathic osteoporosis. Levels of specific miRNAs significantly correlate with PTH, suggesting that bone remodeling in PHPT may be mediated in part by PTH-induced changes in miRNA.

Prevention of eating disorders: 2023 in review.

This review of 16 prevention-related publications in Eating Disorders during 2022 is framed by three models: (1) Mental Health Intervention Spectrum: health promotion → types of prevention → case identification/referral → treatment; (2) the prevention cycle: rationale and theory, shaped by critical reviews → clarifying risk and protective factors → program innovation and feasibility studies → efficacy and effectiveness research → program dissemination; and (3) definitions of and links between disordered eating (DE) and eating disorders (EDs). Seven articles fell into the category of prevention rationale (including screening studies) and relevant reviews, while nine articles addressed correlates of/risk factors (RFs) for various aspects of DE and EDs. One implication of the 16 articles reviewed is that RF research toward construction of selective and indicated prevention programs for an expanding array of diverse at-risk groups needs to address, from a nuanced, intersectional framework, a broad range of factors beyond negative body image and internalization of beauty ideals. Another implication is that, to expand and improve current and forthcoming prevention programs, and to shape effective advocacy for prevention-oriented social policy, the field in general and Eating Disorders in particular need more scholarship in the form of critical reviews and meta-analyses; protective factor research; prevention program development and multi-stage evaluation; and case studies of multi-step activism at the local, state (province, region), and national levels.

Is EGD Needed in all Patients after Suicidal or Exploratory Caustic Ingestions?

BACKGROUND: Caustic ingestions are relatively uncommon, but remain a significant source of morbidity. Patients with caustic injury often undergo an urgent EGD, although it is not clear if an EGD is routinely needed in an asymptomatic patient. The study has two primary objectives; 1) to determine the utility of routine EGD in asymptomatic suicidal caustic ingestions; 2) to determine if asymptomatic unintentional acidic ingestions can be managed with observation alone, similar to basic ingestions. METHODS: This retrospective study, which took place at 14 hospitals in three countries evaluated all patients who presented with a caustic ingestion between 2014-2020. The presence of symptoms and esophageal injury, demographic information, pH of ingested substance, reason for the ingestion, and outcome were recorded. RESULTS: 409 patients were identified; 203 (46.9%) were male. The median (IQR) age was 18 (4-31) years; overall range 10 months to 78 years. Suicidal ingestions accounted for 155 (37.9%) of cases. Dysphagia or dysphonia were more likely in those with significant esophageal injury compared to those without (59.3% vs. 12.6% respectively; OR 10.1; 95% CI 4.43-23.1). Among 27 patients with significant esophageal injury, 48% were found in suicidal patients, compared with 51.9% in non-suicidal patients (p = NS). On multivariate regression, there was no difference in the rate of significant esophageal injury among suicidal vs. non suicidal patients (aOR 1.55; p = 0.45, 95% CI 0.45-5.33). Most ingestions involved basic substances (332/409; 81.2%). Unknown or mixed ingestions accounted for 25 (6.11%) of the ingestions. Significant esophageal burns were found in 6/52 (11.5%) of acid ingestions, compared with 21/332 (6.3%) of basic ingestions. Of the 42 cases of acidic ingestions without dysphagia or odynophagia, 2 (4.8%; 0.58-16.1%) had significant esophageal burns, compared with 9 (3.2%; 95% CI 1.4-5.9%) of the 284 basic ingestions; p = 0.64). On multivariate logistic regression, patients with acidic ingestions were not more likely to experience a significant burn (aOR 1.7; p = 0.11, 95% CI 0.9-3.1) compared to those with basic ingestions. No patient with significant esophageal burns was asymptomatic. CONCLUSION: In this study, there was no statistical differences in the rates of significant burns between acidic and basic caustic ingestions. There were no significant esophageal injuries noted among asymptomatic patients.

Quantitative proteome dynamics across embryogenesis in a model chordate.

The evolution of gene expression programs underlying the development of vertebrates remains poorly characterized. Here, we present a comprehensive proteome atlas of the model chordate Ciona, covering eight developmental stages and ∼7,000 translated genes, accompanied by a multi-omics analysis of co-evolution with the vertebrate Xenopus. Quantitative proteome comparisons argue against the widely held hourglass model, based solely on transcriptomic profiles, whereby peak conservation is observed during mid-developmental stages. Our analysis reveals maximal divergence at these stages, particularly gastrulation and neurulation. Together, our work provides a valuable resource for evaluating conservation and divergence of multi-omics profiles underlying the diversification of vertebrates.

A blueprint most wonderful, the homeobox discovery.

This is a personal, non-linear summary of the discovery of the homeobox, a short DNA sequence encoding a DNA-binding domain conserved in developmental control genes. It is based on our recollections, a few decaying lab notebooks and letters, the early research papers we published, and conversations with a few colleagues who were in Basel at the time. It presents a simple story, when the research we did was anything but, with failed experiments, blind alleys and dumb ideas. Homeobox DNA sequences were independently discovered by Matt Scott and Amy Weiner in Thomas Kaufmann's lab at Indiana University ( Scott and Weiner, 1984). The accompanying Perspective from Scott (2024), provides their fascinating story.

What are tethering elements?

High-resolution Micro-C maps identified a specialized class of regulatory DNAs termed 'tethering elements' (TEs) in Drosophila. These 300-500-bp elements facilitate specific long-range genomic associations or loops. The POZ-containing transcription factor GAF (GAGA-associated factor) contributes to loop formation. Tether-tether interactions accelerate Hox gene activation by distal enhancers, and coordinate transcription of duplicated genes (paralogs) through promoter-promoter associations. Some TEs engage in ultra-long-range enhancer-promoter and promoter-promoter interactions (meta-loops) in the Drosophila brain. We discuss the basis for tether-tether specificity and speculate on the occurrence of similar elements in vertebrate genomes.

Remdesivir Discontinuation Decisions Based on Thresholds of Aminotransferase in an Observational Registry.

BACKGROUND: Remdesivir is an antiviral approved by the US Food and Drug Administration (FDA) for treatment of coronavirus disease 2019 (COVID-19), and aminotransferase elevation is commonly reported. Thresholds to be considered for discontinuation due to alanine aminotransferase (ALT) elevation differ between the FDA and European Medicines Agency (EMA). The primary objective was to describe aminotransferase thresholds being used in real-world practice for discontinuation of remdesivir in patients with COVID-19, and compare them with labeled recommendations. METHODS: This study used a descriptive design based on an ongoing national registry of adverse events, the FDA ACMT COVID-19 ToxIC (FACT) pharmacovigilance project, with 17 participating health systems in the USA. Cases were identified retrospectively for an 18-month period (23 November 2020-18 May 2022). Classification of discontinuation as premature and due to aminotransferases was based on chart documentation by the treating team. RESULTS: Of 1026 cases in the FACT registry, 116 cases were included with supplemental data forms completed for aminotransferase elevation with remdesivir, defined a priori for inclusion as ALT doubling or increasing by ≥ 50 U/L. ALT was elevated prior to remdesivir in 47% and increased above baseline during dosing by a median of 92 U/L [interquartile range (IQR) 51-164, max 8350]. Remdesivir was discontinued early in 37 (31.9%) patients due to elevated aminotransferases. The ALT threshold for premature discontinuation was median 200 U/L (IQR 145-396, range 92-5743). Among patients with premature discontinuation of remdesivir for aminotransferase elevation, only 21.6% met FDA criteria to consider discontinuation, and 40.5% met prior EMA criteria to consider discontinuation. CONCLUSION: In this descriptive study of real-world practice in the USA, clinicians are overall making more conservative treatment decisions than are recommended for consideration in approved drug labeling of discontinuation, with wide variation in the aminotransferase thresholds being used.

IUPHAR-review: The integration of classic psychedelics into current substance use disorder treatment models.

Substance use disorders (SUDs) have an enormous impact on public health. With classic psychedelic-assisted therapies showing initial promise in treating multiple SUDs, it is possible that these treatments will become legally available options for patients with SUDs in the future. This article highlights how classic psychedelic-assisted therapies might be integrated into current clinical practice. We first describe contemporary evidence-based treatments for SUDs and highlight how classic psychedelic-assisted therapies might fit within each treatment. We suggest that classic psychedelic-assisted therapies can be integrated into most mainstream evidence-based SUD treatments that are currently used in clinical settings, indicating broad compatibility of classic psychedelics with contemporary SUD treatment paradigms.

Transplanted human neural stem cells rescue phenotypes in zQ175 Huntington's disease mice and innervate the striatum.

Huntington's disease (HD), a genetic neurodegenerative disorder, primarily affects the striatum and cortex with progressive loss of medium-sized spiny neurons (MSNs) and pyramidal neurons, disrupting cortico-striatal circuitry. A promising regenerative therapeutic strategy of transplanting human neural stem cells (hNSCs) is challenged by the need for long-term functional integration. We previously described that, with short-term hNSC transplantation into the striatum of HD R6/2 mice, human cells differentiated into electrophysiologically active immature neurons, improving behavior and biochemical deficits. Here, we show that long-term (8 months) implantation of hNSCs into the striatum of HD zQ175 mice ameliorates behavioral deficits, increases brain-derived neurotrophic factor (BDNF) levels, and reduces mutant huntingtin (mHTT) accumulation. Patch clamp recordings, immunohistochemistry, single-nucleus RNA sequencing (RNA-seq), and electron microscopy demonstrate that hNSCs differentiate into diverse neuronal populations, including MSN- and interneuron-like cells, and form connections. Single-nucleus RNA-seq analysis also shows restoration of several mHTT-mediated transcriptional changes of endogenous striatal HD mouse cells. Remarkably, engrafted cells receive synaptic inputs, innervate host neurons, and improve membrane and synaptic properties. Overall, the findings support hNSC transplantation for further evaluation and clinical development for HD.

Cereblon influences the timing of muscle differentiation in Ciona tadpoles.

Thalidomide has a dark history as a teratogen, but in recent years, its derivates have been shown to function as potent chemotherapeutic agents. These drugs bind cereblon (CRBN), the substrate receptor of an E3 ubiquitin ligase complex, and modify its degradation targets. Despite these insights, remarkably little is known about the normal function of cereblon in development. Here, we employ Ciona, a simple invertebrate chordate, to identify endogenous Crbn targets. In Ciona, Crbn is specifically expressed in developing muscles during tail elongation before they acquire contractile activity. Crbn expression is activated by Mrf, the ortholog of MYOD1, a transcription factor important for muscle differentiation. CRISPR/Cas9-mediated mutations of Crbn lead to precocious onset of muscle contractions. By contrast, overexpression of Crbn delays contractions and is associated with decreased expression of contractile protein genes such as troponin. This reduction is possibly due to reduced Mrf protein levels without altering Mrf mRNA levels. Our findings suggest that Mrf and Crbn form a negative feedback loop to control the precision of muscle differentiation during tail elongation.