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We describe the case of a 27-year-old male, previously healthy though with a social history notable for recreational cocaine use, who developed bone marrow failure due to aplastic anemia (AA) with associated serous fat atrophy (SFA). After the SFA was corrected with nutritional supplementation, the patient underwent successful allogeneic, haploidentical stem cell transplantation with a regimen designed to treat AA. To our knowledge, this is the first case of hematopoietic stem cell transplantation (HSCT) performed following correction of SFA. Herein we propose our novel hypothesis that SFA, once resolved, is not a contraindication to stem cell transplantation, which we believe adds valuable insight toward an improved understanding of nutrition’s role in HSCT. Additionally, the AA is thought to be toxin-induced and specifically levamisole-mediated after exposure to levamisole-adulterated cocaine. We highlight potential connections between levamisole, AA, and SFA and call for further efforts to understand these relationships—especially as the use of levamisole as a cocaine adulterant continues to rise across the globe.

IntroductionRecent advances in genetic data collection utilizing next-generation DNA sequencing technologies have the potential to greatly aid the taxonomic assessment of species of conservation concern, particularly species that have been difficult to describe using morphology alone. Accurate taxonomic descriptions aided by genetic data are essential to directing limited conservation resources to species most in need. Sclerocactus glaucus is a plant endemic to Western Colorado that is currently listed as Threatened under the Endangered Species Act (ESA). However, in 2023, the U. S. Fish and Wildlife Service proposed de-listing S. glaucus from the ESA due to recovery of the species. Previous research had found substantial genetic structure between populations in the northern part of the S. glaucus range relative to the majority of the species distribution.MethodsIn this study we utilized double-digest Restriction-site Associated DNA sequencing (RAD-seq) in order to better understand the genetic structure of S. glaucus.ResultsOur results indicate that S. glaucus contains two distinct evolutionary lineages that warrant recognition at the level of species, with what was previously described as S. glaucus North being recognized as Sclerocactus dawsoniae.DiscussionThe newly described S. dawsoniae has a limited estimated number of individuals, low levels of nucleotide diversity, a very narrow geographic range, and an uneven geographic distribution with most plants being found in a single management area, all of which supports continued direct conservation of this species. In contrast, S. glaucus has a large estimated minimum population size, a broad geographic range that includes numerous protected areas, and adequate levels of genetic diversity. Without further conservation action, a delisting decision for S. glaucus will simultaneously remove all Endangered Species Act protections for S. dawsoniae. The current work demonstrates the importance of having robust genetic datasets when planning conservation activities for species of concern. Moving forward, we recommend that government stakeholders prioritize supporting genetic studies of endangered species prior to making any changes to listing decisions.

Youth with classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency exhibit an increased prevalence of obesity, early adiposity rebound, and increased abdominal adiposity compared to unaffected youth. Current obesity management in CAH largely focuses on lifestyle modifications. There is evidence that topiramate therapy is effective in reducing body mass index (BMI), as well as visceral adipose tissue (VAT), in unaffected adolescents with exogenous obesity. However, little is known about the efficacy of topiramate in patients with classical CAH. We report on a 17-year-old female with severe obesity and salt-wasting CAH due to 21-hydroxylase deficiency, who demonstrated reductions in BMI, as well as abdominal visceral and subcutaneous adipose tissue (SAT) while on topiramate therapy. The patient was diagnosed with classical CAH as a newborn with a 17-hydroxyprogesterone 11,000 ng/dL. She had a BMI over the 95th percentile at 3 years of age, followed by unremitting obesity. At 17 years old, she was started on topiramate to treat chronic migraines. Following three years of topiramate therapy, her BMI z-score decreased from +2.6 to +2.1. After four years of therapy, her waist circumference decreased from 110 to 101 cm, abdominal VAT decreased substantially by 34.2%, and abdominal SAT decreased by 25.6%. Topiramate therapy was associated with effective weight loss and reduced central adiposity in an adolescent with classical CAH and severe obesity, without any side effects. Further study is warranted regarding topiramate therapy in obese youth with classical CAH and increased central adiposity, who are at higher risk for significant morbidity.

High-level potential energy surfaces for three reactions of hypobromous acid with atomic hydrogen were computed at the CCSDTQ/CBS//CCSDT(Q)/complete basis set level of theory. Focal point analysis was utilized to extrapolate energies and gradients for energetics and optimizations, respectively. The H attack at Br and subsequent Br–O cleavage were found to proceed barrierlessly. The slightly submerged transition state lies −0.2 kcal mol−1 lower in energy than the reactants and produces OH and HBr. The two other studied reaction paths are the radical substitution to produce H2O and Br with a 4.0 kcal mol−1 barrier and the abstraction at hydrogen to produce BrO and H2 with an 11.2 kcal mol−1 barrier. The final product energies lie −37.2, −67.9, and −7.3 kcal mol−1 lower in energy than reactants, HOBr + H, for the sets of products OH + HBr, H2O + Br, and H2 + BrO, respectively. Additive corrections computed for the final energetics, particularly the zero-point vibrational energies and spin–orbit corrections, significantly impacted the final stationary point energies, with corrections up to 6.2 kcal mol−1. [ABSTRACT FROM AUTHOR]

Vancomycin is a broad-spectrum antibiotic widely used in cases of suspected sepsis in premature neonates. While appropriate and potentially lifesaving in this setting, early-life antibiotic exposure alters the developing microbiome and is associated with an increased risk of deadly complications, including late-onset sepsis (LOS) and necrotizing enterocolitis (NEC). Recent studies show that neonatal vancomycin treatment disrupts postnatal enteric nervous system (ENS) development in mouse pups, which is in part dependent upon neuroimmune interactions. This suggests that early-life antibiotic exposure could disrupt these interactions in the neonatal gut. Notably, a subset of tissue-resident intestinal macrophages, muscularis macrophages, has been identified as important contributors to the development of postnatal ENS. We hypothesized that vancomycin-induced neonatal dysbiosis impacts postnatal ENS development through its effects on macrophages. Using a mouse model, we found that exposure to vancomycin in the first 10 days of life, but not in adult mice, resulted in an expansion of pro-inflammatory colonic macrophages by increasing the recruitment of bone-marrow-derived macrophages. Single-cell RNA sequencing of neonatal colonic macrophages revealed that early-life vancomycin exposure was associated with an increase in immature and inflammatory macrophages, consistent with an influx of circulating monocytes differentiating into macrophages. Lineage tracing confirmed that vancomycin significantly increased the non-yolk-sac-derived macrophage population. Consistent with these results, early-life vancomycin exposure did not expand the colonic macrophage population nor decrease enteric neuron density in CCR2-deficient mice. Collectively, these findings demonstrate that early-life vancomycin exposure alters macrophage number and phenotypes in distinct ways compared with vancomycin exposure in adult mice and results in altered ENS development.

BackgroundDisordered bone mineral metabolism and low vitamin D concentrations are associated with cardiovascular abnormalities; few studies have evaluated this relationship in HIV-infected youth.SettingThe Adolescent Master Protocol is a Pediatric HIV/AIDS Cohort Study network study conducted across 14 US sites.MethodsAmong perinatally HIV-infected (PHIV) and perinatally HIV-exposed but uninfected (PHEU) youth enrolled in the Adolescent Master Protocol, we evaluated associations of vitamin D [measured as 25-hydroxy-vitamin D (25-OHD)], parathyroid hormone (PTH), calcium, phosphate, and fibroblast growth factor-23 (FGF-23) concentrations with echocardiographic measures of left ventricular (LV) structure, function, and concentrations of NT-proBNP, a biomarker of cardiac damage.ResultsAmong 485 participants (305 PHIV and 180 PHEU) with echocardiograms and bone mineralization measures, low 25-OHD (65 pg/mL) was identified more often among PHIV participants than PHEU participants (9% vs 3%, P = 0.02). After adjusting for HIV status and demographic covariates, both low 25-OHD and elevated PTH were associated with lower mean LV mass z-scores, whereas elevated PTH was associated with higher mean fractional shortening z-scores. Participants with low 25-OHD also had slightly higher mean LV end-systolic wall stress z-scores, but differences were more pronounced in PHEU participants than in PHIV participants. FGF-23 was inversely related to end-diastolic septal thickness, both overall and among PHIV participants.ConclusionsIn this cohort of PHIV and PHEU youth, we observed associations of 25-OHD, PTH, and FGF-23 with both structural and functional cardiac parameters, supporting links between bone mineral metabolism and cardiac status.

Alloreactivity can drive autoimmune syndromes. After allogeneic hematopoietic stem cell transplantation (allo-HCT), chronic graft-versus-host disease (cGVHD), a B cell–associated autoimmune-like syndrome, commonly occurs. Because donor-derived B cells continually develop under selective pressure from host alloantigens, aberrant B cell receptor (BCR) activation and IgG production can emerge and contribute to cGVHD pathobiology. To better understand molecular programing of B cells in allo-HCT, we performed scRNA-Seq analysis on high numbers of purified B cells from patients. An unsupervised analysis revealed 10 clusters, distinguishable by signature genes for maturation, activation, and memory. Within the memory B cell compartment, we found striking transcriptional differences in allo-HCT patients compared with healthy or infected individuals, including potentially pathogenic atypical B cells (ABCs) that were expanded in active cGVHD. To identify intrinsic alterations in potentially pathological B cells, we interrogated all clusters for differentially expressed genes (DEGs) in active cGVHD versus patients who never had signs of immune tolerance loss (no cGVHD). Active cGVHD DEGs occurred in both naive and BCR-activated B cell clusters. Remarkably, some DEGs occurred across most clusters, suggesting common molecular programs that may promote B cell plasticity. Our study of human allo-HCT and cGVHD provides understanding of altered B cell memory during chronic alloantigen stimulation.

Fertilizing maize at an optimum nitrogen rate is imperative to maximize productivity and sustainability. Using a combination of long-term (n = 379) and short-term (n = 176) experiments, we show that the economic optimum nitrogen rate for US maize production has increased by 2.7 kg N ha−1 yr−1 from 1991 to 2021 (1.2% per year) simultaneously with grain yields and nitrogen losses. By accounting for societal cost estimates for nitrogen losses, we estimate an environmental optimum rate, which has also increased over time but at a lower rate than the economic optimum nitrogen rate. Furthermore, we provide evidence that reducing rates from the economic to environmental optimum nitrogen rate could reduce US maize productivity by 6% while slightly reducing nitrogen losses. We call for enhanced assessments and predictability of the economic and environmental optimum nitrogen rate to meet rising maize production while avoiding unnecessary nitrogen losses. Maize production is dependent on Nitrogen fertilizer input. Here, the authors use long-term and short-term experiments to demonstrate that economic and environmental optimum nitrogen fertilization rates have increased between 1991 and 2021. [ABSTRACT FROM AUTHOR]