Clonal multi-omics reveals Bcor as a negative regulator of emergency dendritic cell development.

Despite advances in single-cell multi-omics, a single stem or progenitor cell can only be tested once. We developed clonal multi-omics, in which daughters of a clone act as surrogates of the founder, thereby allowing multiple independent assays per clone. With SIS-seq, clonal siblings in parallel "sister" assays are examined either for gene expression by RNA sequencing (RNA-seq) or for fate in culture. We identified, and then validated using CRISPR, genes that controlled fate bias for different dendritic cell (DC) subtypes. This included Bcor as a suppressor of plasmacytoid DC (pDC) and conventional DC type 2 (cDC2) numbers during Flt3 ligand-mediated emergency DC development. We then developed SIS-skew to examine development of wild-type and Bcor-deficient siblings of the same clone in parallel. We found Bcor restricted clonal expansion, especially for cDC2s, and suppressed clonal fate potential, especially for pDCs. Therefore, SIS-seq and SIS-skew can reveal the molecular and cellular mechanisms governing clonal fate.

The Clinical Usefulness of a Glaucoma Polygenic Risk Score in 4 Population-Based European Ancestry Cohorts.

PURPOSE: We used a polygenic risk score (PRS) to identify high-risk groups for primary open-angle glaucoma (POAG) within population-based cohorts. DESIGN: Secondary analysis of 4 prospective population-based studies. PARTICIPANTS: We included four European-ancestry cohorts: the United States-based Nurses' Health Study, Nurses' Health Study 2, and the Health Professionals Follow-up Study and the Rotterdam Study (RS) in The Netherlands. The United States cohorts included female nurses and male health professionals ≤ 55 years of age. The RS included residents ≤ 45 years of age living in Rotterdam, The Netherlands. METHODS: Polygenic risk score weights were estimated by applying the lassosum method on imputed genotype and phenotype data from the UK Biobank. This resulted in 144 020 variants, single nucleotide polymorphism and insertions or deletions, with nonzero ßs that we used to calculate a PRS in the target populations. Using multivariable Cox proportional hazard models, we estimated the relationship between the standardized PRS and relative risk for POAG. Additionally, POAG prediction was tested by calculating these models' concordance (Harrell's C statistic). Finally, we assessed the association between PRS tertiles and glaucoma-related traits. MAIN OUTCOME MEASURES: The relative risk for POAG and Harrell's C statistic. RESULTS: Among 1046 patients and 38 809‬ control participants, the relative risk (95% confidence interval) for POAG for participants in the highest PRS quintile was 3.99 (3.08-5.18) times higher in the United States cohorts and 4.89 (2.93-8.17) times higher in the RS, compared with participants with median genetic risk (third quintile). Combining age, sex, intraocular pressure of more than 25 mmHg, and family history resulted in a meta-analyzed concordance of 0.75 (95% CI, 0.73-0.75). Adding the PRS to this model improved the concordance to 0.82 (95% CI, 0.80-0.84). In a meta-analysis of all cohorts, patients in the highest tertile showed a larger cup-to-disc ratio at diagnosis, by 0.10 (95% CI, 0.06 0.14), and a 2.07-fold increased risk of requiring glaucoma surgery (95% CI, 1.19-3.60). CONCLUSIONS: Incorporating a PRS into a POAG predictive model improves identification concordance from 0.75 up to 0.82, supporting its potential for guiding more cost-effective screening strategies. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Microbial modulation via cross-fostering prevents the effects of pervasive environmental stressors on microglia and social behavior, but not the dopamine system.

Environmental toxicant exposure, including air pollution, is increasing worldwide. However, toxicant exposures are not equitably distributed. Rather, low-income and minority communities bear the greatest burden, along with higher levels of psychosocial stress. Both air pollution and maternal stress during pregnancy have been linked to neurodevelopmental disorders such as autism, but biological mechanisms and targets for therapeutic intervention remain poorly understood. We demonstrate that combined prenatal exposure to air pollution (diesel exhaust particles, DEP) and maternal stress (MS) in mice induces social behavior deficits only in male offspring, in line with the male bias in autism. These behavioral deficits are accompanied by changes in microglial morphology and gene expression as well as decreased dopamine receptor expression and dopaminergic fiber input in the nucleus accumbens (NAc). Importantly, the gut-brain axis has been implicated in ASD, and both microglia and the dopamine system are sensitive to the composition of the gut microbiome. In line with this, we find that the composition of the gut microbiome and the structure of the intestinal epithelium are significantly shifted in DEP/MS-exposed males. Excitingly, both the DEP/MS-induced social deficits and microglial alterations in males are prevented by shifting the gut microbiome at birth via a cross-fostering procedure. However, while social deficits in DEP/MS males can be reversed by chemogenetic activation of dopamine neurons in the ventral tegmental area, modulation of the gut microbiome does not impact dopamine endpoints. These findings demonstrate male-specific changes in the gut-brain axis following DEP/MS and suggest that the gut microbiome is an important modulator of both social behavior and microglia.

Characterization of the Membrane-Associated Electron-Bifurcating Flavoenzyme EtfABCX from the Hyperthermophilic Bacterium Thermotoga maritima.

Electron bifurcation is an energy-conservation mechanism in which a single enzyme couples an exergonic reaction with an endergonic one. Heterotetrameric EtfABCX drives the reduction of low-potential ferredoxin (E°' ∼ -450 mV) by oxidation of the midpotential NADH (E°' = -320 mV) by simultaneously coupling the reaction to reduction of the high-potential menaquinone (E°' = -74 mV). Electron bifurcation occurs at the NADH-oxidizing bifurcating-flavin adenine dinucleotide (BF-FAD) in EtfA, which has extremely crossed half-potentials and passes the first, high-potential electron to an electron-transferring FAD and via two iron-sulfur clusters eventually to menaquinone. The low-potential electron on the BF-FAD semiquinone simultaneously reduces ferredoxin. We have expressed the genes encodingThermotoga maritimaEtfABCX in E. coli and purified the EtfABCX holoenzyme and the EtfAB subcomplex. The bifurcation activity of EtfABCX was demonstrated by using electron paramagnetic resonance (EPR) to follow accumulation of reduced ferredoxin. To elucidate structural factors that impart the bifurcating ability, EPR and NADH titrations monitored by visible spectroscopy and dye-linked enzyme assays have been employed to characterize four conserved residues, R38, P239, and V242 in EtfA and R140 in EtfB, in the immediate vicinity of the BF-FAD. The R38, P239, and V242 variants showed diminished but still significant bifurcation activity. Despite still being partially reduced by NADH, the R140 variant had no bifurcation activity, and electron transfer to its two [4Fe-4S] clusters was prevented. The role of R140 is discussed in terms of the bifurcation mechanism in EtfABCX and in the other three families of bifurcating enzymes.

The reductive half-reaction of two bifurcating electron-transferring flavoproteins: Evidence for changes in flavin reduction potentials mediated by specific conformational changes.

The EtfAB components of two bifurcating flavoprotein systems, the crotonyl-CoA-dependent NADH:ferredoxin oxidoreductase from the bacterium Megasphaera elsdenii and the menaquinone-dependent NADH:ferredoxin oxidoreductase from the archaeon Pyrobaculum aerophilum, have been investigated. With both proteins, we find that removal of the electron-transferring flavin adenine dinucleotide (FAD) moiety from both proteins results in an uncrossing of the reduction potentials of the remaining bifurcating FAD; this significantly stabilizes the otherwise very unstable semiquinone state, which accumulates over the course of reductive titrations with sodium dithionite. Furthermore, reduction of both EtfABs depleted of their electron-transferring FAD by NADH was monophasic with a hyperbolic dependence of reaction rate on the concentration of NADH. On the other hand, NADH reduction of the replete proteins containing the electron-transferring FAD was multiphasic, consisting of a fast phase comparable to that seen with the depleted proteins followed by an intermediate phase that involves significant accumulation of FAD⋅-, again reflecting uncrossing of the half-potentials of the bifurcating FAD. This is then followed by a slow phase that represents the slow reduction of the electron-transferring FAD to FADH-, with reduction of the now fully reoxidized bifurcating FAD by a second equivalent of NADH. We suggest that the crossing and uncrossing of the reduction half-potentials of the bifurcating FAD is due to specific conformational changes that have been structurally characterized.

Creating ophthalmology experiences in undergraduate medical education: pilot of a cased-based learning ophthalmology tool.

PURPOSE: To evaluate medical student perceptions of a novel ophthalmology resource delivered through facilitated workshops in the core clerkship curriculum. METHODS: We created www.2020sim.com, a free case-based learning (CBL) ophthalmology tool, adapted from NephSIM (www.nephsim.com). The tool was first piloted with the internal medicine (IM) residents. After confirming a need, we focused on undergraduate medical education (UME) by expanding the 20/20 SIM content and partnering with the neurology (pilot academic year [AY] 2020-2021) and pediatric clerkships (pilot AY 2021-2022) to deliver a facilitated one-hour ophthalmology workshop within each clerkship's didactic curriculum. We evaluated the tool using pre- and post-surveys and knowledge assessments. RESULTS: Of 80 IM residents, 33 (41.3%) completed the needs assessment. Of the 25 residents who attended the workshop, 23 (92.0%) completed the exit survey. IM residents reported discomfort in several ophthalmology domains (9 of 14 rated mean score < 3.0), confirming a need. Most (n = 21/23, 91.3%) rated the tool as good/excellent. Of 145 neurology clerkship students, 125 (86.2%) and at least 88 (60.7%) students completed the pre- and post-test/exit surveys, respectively. On average, participants highly rated the tool, perceiving 20/20 SIM to be relevant to their education [4.1 (0.8)]. Mean pre- to post-test knowledge scores increased from 7.5 to 8.5/10.0 points (p < 0.001). Of the 136 pediatric clerkship students, 67 (49.3%) and 51 (37.5%) completed the pre- and post-surveys, respectively. Respondents perceived increased comfort with ophthalmology topics after the facilitated workshop [3.8 (0.8)]. Mean pre- to post-test knowledge scores trended from 1.8 to 2.0/5.0 points (p = 0.30). Collectively, 20/139 (14.4%) of exit survey respondents visited www.2020sim.com within 1 month after the workshop. CONCLUSION: After identifying areas of greatest need with residents, we partnered with core clerkships to deliver cross-disciplinary ophthalmology content in UME. We found high engagement with 20/20 SIM, with trends toward increased knowledge.

Alcohol, Intraocular Pressure, and Open-Angle Glaucoma: A Systematic Review and Meta-analysis.

TOPIC: This systematic review and meta-analysis summarizes the existing evidence for the association of alcohol use with intraocular pressure (IOP) and open-angle glaucoma (OAG). CLINICAL RELEVANCE: Understanding and quantifying these associations may aid clinical guidelines or treatment strategies and shed light on disease pathogenesis. The role of alcohol, a modifiable factor, in determining IOP and OAG risk also may be of interest from an individual or public health perspective. METHODS: The study protocol was preregistered in the Open Science Framework Registries (https://osf.io/z7yeg). Eligible articles (as of May 14, 2021) from 3 databases (PubMed, Embase, Scopus) were independently screened and quality assessed by 2 reviewers. All case-control, cross-sectional, and cohort studies reporting a quantitative effect estimate and 95% confidence interval (CI) for the association between alcohol use and either IOP or OAG were included. The evidence for the associations with both IOP and OAG was qualitatively summarized. Effect estimates for the association with OAG were pooled using random effects meta-analysis. Studies not meeting formal inclusion criteria for systematic review, but with pertinent results, were also appraised and discussed. Certainty of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework. RESULTS: Thirty-four studies were included in the systematic review. Evidence from 10 studies reporting an association with IOP suggests that habitual alcohol use is associated with higher IOP and prevalence of ocular hypertension (IOP > 21 mmHg), although absolute effect sizes were small. Eleven of 26 studies, comprising 173 058 participants, that tested for an association with OAG met inclusion criteria for meta-analysis. Pooled effect estimates indicated a positive association between any use of alcohol and OAG (1.18; 95% confidence interval [CI], 1.02-1.36; P = 0.03; I2 = 40.5%), with similar estimates for both prevalent and incident OAG. The overall GRADE certainty of evidence was very low. CONCLUSIONS: Although this meta-analysis suggests a harmful association between alcohol use and OAG, our results should be interpreted cautiously given the weakness and heterogeneity of the underlying evidence base, the small absolute effect size, and the borderline statistical significance. Nonetheless, these findings may be clinically relevant, and future research should focus on improving the quality of evidence.

The Simultaneous Use of Spring-Mediated Cranioplasty and Distraction Osteogenesis as a Safe Modality for Multi-Suture Craniosynostosis.

ABSTRACT: Craniosynostosis caused by premature fusion of the cranial sutures most commonly involves a single suture. Less commonly, multiple sutures may fuse prematurely resulting in complex craniosynostosis. The authors present 1 case of a patient with unilateral sagittal and unilateral lambdoid craniosynostosis treated safely simultaneous with spring-mediated cranioplasty and distraction osteogenesis.

"What are you going to do, Protest the Wind?": Community Perceptions of Emergent and Worsening Coastal Erosion from the Remote Bering Sea Community of St. Paul, Alaska.

The state of Alaska is experiencing increased coastal erosion due to climatic changes that threaten shoreline, infrastructure, and Alaska Native ways of life. While several Alaska Native villages have been impacted by severe erosion, additional communities face burgeoning erosion concerns. St. Paul, a remote island located in the Bering Sea, Alaska, and home to ~450 Unangan, or Aleut, residents, is experiencing relatively new erosion and associated flooding issues. This study aimed to inform St. Paul's erosion monitoring and climate adaptation strategies by documenting community perceptions of coastal erosion as an ecological and social threat within a broader context of multiple established climate stressors. We interviewed 21 residents to answer: (1) what are the community's perceptions of erosion on St. Paul in the context of the island's other environmental concerns?; (2) do current perceptions of erosion affect how local governing and management entities address erosion impacts?; and (3) how does erosion relate to and impact Unangan cultural traditions and heritage? Residents identified six locations of primary concern, owing to how erosion of those areas impact their culture, subsistence practices, and sense of place. We suggest methods in which local entities can better support proactive climate adaptation and mitigation measures and utilize resources for community-driven adaption planning. By documenting perspectives in Indigenous communities on emergent climate impacts, as well as perceptions of adaptation planning and implementation, it can establish the foundation for more collaborative, culturally relevant, and successful community-driven climate adaptation planning.

The MAIT TCRß chain contributes to discrimination of microbial ligand.

Mucosal-associated invariant T (MAIT) cells are key players in the immune response against microbial infection. The MAIT T-cell receptor (TCR) recognizes a diverse array of microbial ligands, and recent reports have highlighted the variability in the MAIT TCR that could further contribute to discrimination of ligand. The MAIT TCR complementarity determining region (CDR)3ß sequence displays a high level of diversity across individuals, and clonotype usage appears to be dependent on antigenic exposure. To address the relationship between the MAIT TCR and microbial ligand, we utilized a previously defined panel of MAIT cell clones that demonstrated variability in responses against different microbial infections. Sequencing of these clones revealed four pairs, each with shared (identical) CDR3α and different CDR3ß sequences. These pairs demonstrated varied responses against microbially infected dendritic cells as well as against 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil, a ligand abundant in Salmonella enterica serovar Typhimurium, suggesting that the CDR3ß contributes to differences in ligand discrimination. Taken together, these results highlight a key role for the MAIT CDR3ß region in distinguishing between MR1-bound antigens and ligands.

Neonatal immune challenge induces female-specific changes in social behavior and somatostatin cell number.

Decreases in social behavior are a hallmark aspect of acute "sickness behavior" in response to infection. However, immune insults that occur during the perinatal period may have long-lasting consequences for adult social behavior by impacting the developmental organization of underlying neural circuits. Microglia, the resident immune cells of the central nervous system, are sensitive to immune stimulation and play a critical role in the developmental sculpting of neural circuits, making them likely mediators of this process. Here, we investigated the impact of a postnatal day (PND) 4 lipopolysaccharide (LPS) challenge on social behavior in adult mice. Somewhat surprisingly, neonatal LPS treatment decreased sociability in adult female, but not male mice. LPS-treated females also displayed reduced social interaction and social memory in a social discrimination task as compared to saline-treated females. Somatostatin (SST) interneurons within the anterior cingulate cortex (ACC) have recently been suggested to modulate a variety of social behaviors. Interestingly, the female-specific changes in social behavior observed here were accompanied by an increase in SST interneuron number in the ACC. Finally, these changes in social behavior and SST cell number do not appear to depend on microglial inflammatory signaling, because microglia-specific genetic knock-down of myeloid differentiation response protein 88 (MyD88; the removal of which prevents LPS from increasing proinflammatory cytokines such as TNFα and IL-1ß) did not prevent these LPS-induced changes. This study provides novel evidence for enduring effects of neonatal immune activation on social behavior and SST interneurons in females, largely independent of microglial inflammatory signaling.

Lymphomatoid Papulosis With a Unique T Follicular Helper-Like Phenotype.

Lymphomatoid papulosis (LyP) is a benign skin condition that typically presents with grouped or scattered lesions on the body that self-resolve within weeks or months of onset. LyP belongs to the group of CD30-positive lymphoproliferative disorders. Several histological variants of LyP exist, and the histological features of LyP can overlap with other lymphoproliferative disorders; therefore, both histological and clinical correlations are needed for a proper diagnosis of LyP. We report an unusual case of LyP displaying a T follicular helper cell-like phenotype and histopathologically resembling the primary cutaneous CD4-positive small-sized to medium-sized T-cell lymphoproliferative disorder.

Anaphylaxis following administration of extracorporeal photopheresis for cutaneous T cell lymphoma.

Extracorporeal photopheresis is a non-invasive therapy used for the treatment of a range of T cell disorders, including cutaneous T cell lymphoma. During extracorporeal photopheresis, peripheral blood is removed from the patient and the white blood cells are separated from whole blood via centrifugation. The white blood cells are exposed to psoralen (a photosensitizing agent) and ultraviolet A radiation, causing cell apoptosis. The apoptotic leukocytes are subsequently re-infused into the patient, resulting in the production of tumor suppressor cells and clinical improvement. Extracorporeal photopheresis is generally regarded as safe with few side effects. We report a dermatology patient who developed anaphylaxis after receiving extracorporeal photopheresis for the treatment of leukemic mycosis fungoides. We suspect that our patient's anaphylaxis resulted from exposure to an agent used in extracorporeal photopheresis.

Development of Sézary syndrome following the administration of dupilumab.

Dupilumab is a monoclonal antibody that inhibits interleukin-4 and interleukin-13 signaling. It is the first biologic agent to demonstrate efficacy in treating moderate-to-severe refractory atopic dermatitis [1, 2]. Although dupilumab provides promise for the treatment of atopic and allergic conditions, clinicians should take into account its novelty and the potential for unexpected adverse events. We present a patient who developed Sézary syndrome following the initiation of dupilumab.

Do Sugar-Sweetened Beverages Cause Obesity and Diabetes? Industry and the Manufacture of Scientific Controversy.

This article has been corrected. The original version (PDF) is appended to this article as a Supplement.

Race and Socio-Economic Status Impact Withdrawal of Treatment in Young Traumatic Brain Injury.

CONTEXT: Withdrawal of life-sustaining therapies (WDLST) in young individuals with traumatic brain injury (TBI) is an overwhelming situation often made more stressful by socioeconomic factors that shape health outcomes. Identifying these factors is crucial to developing equitable and goal-concordant care for patients and families. OBJECTIVES: We aimed to identify predictors of WDLST in young patients with 1-TBI. We hypothesized uninsured payment method, race, and co-morbid status are associated with WDLST. METHODS: We queried the 2021 Trauma Quality Improvement Program database for patients <45 years with TBI. Patients with WDLST were compared to patients without WDLST. Multivariable logistic regression (MLR) was performed. RESULTS: 61,115 patients were included, of whom 2,487 (4.1%) underwent WDLST. Patients in the WDLST cohort were older (29 vs 27, P<0.001), more likely to suffer from a penetrating mechanism (29% vs 11%, P<.0001), and have uninsured (22% vs 18%) or other payment method (5% vs 3%) when compared to the non-WDLST cohort. MLR identified age (AOR:1.019, 95% CI 1.014-1.024, P<.0001), non-Hispanic ethnicity (AOR:1.590, 95% CI 1.373-1.841, P<.0001), penetrating mechanism (AOR:3.075, 95% CI 2.727-3.467, P<.0001), systolic blood pressure (AOR: 0.992, 95% CI 0.990-0.993, P<0.0001), advanced directive (AOR:4.987, 95% CI 2.823-8.812, P<.0001), cirrhosis (AOR:3.854, 95% CI 2.641-5.625, P<.0001), disseminated cancer (AOR:6.595, 95% CI 2.370-18.357, P=0.0003), and interfacility transfer (AOR:1.457, 95% CI 1.295-1.640, P<0.0001) as factors associated with WDLST. Black patients were less likely to undergo WDLST when compared to white patients (AOR:0.687, 95% CI 0.603-0.782, P<.0001). CONCLUSION: The decision for WDLST in young patients with severe TBI may be influenced by cultural and socioeconomic factors in addition to clinical considerations.