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Replacing long-lived, rarely disturbed vegetation with short-lived, frequently disturbed vegetation is a widespread phenomenon in the Anthropocene that can influence ecosystem functioning and soil development by reducing the abundance of deep roots. We explore how sources and fate of soil CO2 vary with organic substrate source, abundance of respiring biota (i.e., roots and soil microbes), season, and soil depth. We quantified multiple isotopic signatures of CO2 (δ13C, Δ14C, δ18O) as well as concentrations and δ18O of free O2 in the upper 5 m of soil at sites where root abundances and soil organic C have been previously quantified: in late-successional forests, cultivated fields, and ~ 80 y old regenerating pine forests growing on previously cultivated land. We hypothesized that soil CO2sources would vary across soil depth and land cover, reflecting varying abundances of organic substrates, and seasonally as the dominance of root vs. microbial CO2 production changes through the year. δ13C–CO2 revealed respiration of C4-derived substrates in cultivated fields particularly during the growing season. This effect was not evident in soils of regenerating pine or older hardwood forests, suggesting that ~ 80 y of pine inputs to reforested soils have been sufficient to dominate microbial substrate selection over any remnant, historic agricultural C4 inputs. Δ14C–CO2 diverged by land use at 3 and 5 m, indicating that more recently-produced photosynthate is available for mineralization in forests compared to cultivated plots, and in late-successional forests compared to regenerating pine forests. At 1.5, 3, and 5 m in forested plots we observed evidence of respiratory demands on soil pore space O2. In these soils, we observed declines in [O2] compared to other depths and to the agricultural plots and concurrent increases in δ18O of free O2, consistent with the idea that roots and heterotrophic soil microbes are more active where photosynthate is more available. The δ18O–CO2 values, a likely proxy for δ18O of soil porewater, exhibited 18O enrichment during the winter, when many sampling wells were flooded, compared to growing season values. These data suggest an isotopically-distinct and laterally-flowing source of CO2-laden porewater during winter months. Combined, these datasets document how ~ 80 y of forest regeneration can provide sufficient C inputs to mask any microbial mineralization of decades-old organic inputs, but belowground C inputs still lag those of late successional forests. We also infer that lateral and vertical flows of water can serve as a sink for biotically-generated CO2, and that where deep soil [CO2] is lower due to lower root and microbial activities, production of carbonic acid is also diminished. Where reaction rates are weathering limited, a paucity of deep roots imposed by anthropogenic land cover change thus may limit the production of this agent of soil development and the C sink represented by the silicate weathering it can promote. The data suggest deep and persistent effects of the loss of deeply rooted long-lived vegetation on deep soil C storage and transformations that promote acid-dissolution weathering reactions that help form soil itself. [ABSTRACT FROM AUTHOR]

Mammalian inner ear hair cell loss leads to permanent hearing and balance dysfunction. In contrast to the cochlea, vestibular hair cells of the murine utricle have some regenerative capacity. Whether human utricular hair cells regenerate in vivo remains unknown. Here we procured live, mature utricles from organ donors (9 ears from 6 organ donors) and vestibular schwannoma patients (24 ears from 24 patients), and presented a single-cell transcriptomic atlas at unprecedented resolution. We validated marker genes using immunostaining and RNAscope in situ hybridization and described previously unknown markers of 13 sensory and non-sensory cell types. In addition, we compared and found partial overlap and correlation between transcriptomes of human and mouse hair cells and supporting cells. We further uncovered transcriptomes unique to hair cell precursors, which are validated in both organ donor and vestibular schwannoma utricles. Unexpectedly we found 14-fold more hair cell precursors in vestibular schwannoma utricles, demonstrating the existence of ongoing regeneration in humans. Lastly, supporting cell-to-hair cell trajectory analysis revealed 5 distinct patterns of dynamic gene expression and associated pathways. Our data-set constitutes a foundational resource, accessible via a web-based interface, serving to advance knowledge of the normal and diseased human inner ear. [ABSTRACT FROM AUTHOR]

Aims: Ossifying fibromyxoid tumour is a rare mesenchymal neoplasm predominantly affecting adults characterised by a multinodular growth pattern and the presence of a fibrous pseudocapsule with areas of ossification. Prompted by the recognition of a non-ossifying ossifying fibromyxoid tumour with lipomatous differentiation which caused diagnostic difficulty, we sought to further explore cases of ossifying fibromyxoid tumour with non-osseous heterologous elements., Methods and Results: A search of our institutional and consultation archives revealed three additional cases that demonstrated lipomatous components and two cases with cartilaginous differentiation. RNA-sequencing revealed fusions involving PHF1 (n = 4) or EPC1 (n = 1) in all (five of five) cases tested, including EPC1::PHC1 and JAZF1::PHF1 fusions, which have not been reported before in ossifying fibromyxoid tumour., Conclusion: These six cases expand the histomorphological spectrum of ossifying fibromyxoid tumour, introducing lipomatous differentiation as a hitherto undocumented feature. Awareness of these rare variants will ensure appropriate diagnosis and clinical management., (© 2024 The Author(s). Histopathology published by John Wiley & Sons Ltd.)

Introduction The use of glucagon-like peptide-1 receptor agonists (GLP-1 RA) has gained acceptance in managing diabetic and non-diabetic patients, thanks to its benefits in treating obesity and improving cardiovascular outcomes. The potential ability of GLP-1 RA to cause retained gastric contents (RGC) which can lead to aspiration has led to the recommendation to withhold GLP-1 RA for at least one week prior to elective surgeries and procedures, including upper endoscopies and colonoscopies. However, many co-medications and conditions associated can contribute to delayed gastric emptying (DGE) and these need to be controlled to establish a clear association and incidence, which has been largely missing in most studies and reports. Our aim was to assess clinically significant delayed gastric emptying (CSDGE) related to GLP-1 RA in a "real world" situation by controlling for some common confounding factors. Method We carried out an eight-year retrospective single-center study to assess the relationship between CSDGE and the use of GLP-1 RA among asymptomatic patients undergoing upper endoscopies while controlling for common confounding factors. Result Out of the 3415 patients who had esophagogastroduodenoscopy (EGD) with or without colonoscopy (Ew/woC) during the eight-year period, 129 eligible patients were found to have CSDGE. The use of GLP-1 RA was associated with the lowest percentage frequency distribution of CSDGE, at 2%, and opiate accounted for more percentage frequency distribution, at 35%. The odds ratio for patients on GLP-1 RA who developed CSDGE was 2.5 (95% CI 0.75-8.29). All patients who had CSDGE while on GLP-1 RA were also on other medications or had conditions associated with DGE. Conclusion Our result confirmed the possible effect of confounding factors in the association between CSDGE and GLP-1 RA among asymptomatic patients undergoing Ew/woC. While the need to ensure patients' safety cannot be overemphasized, the proper approach currently favors assessing patients on a case-by-case basis while we await the results of large prospective controlled studies., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Meharry Medical College Institutional Review Board issued approval FWA00003675. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Elimihele et al.)

Background: Desmoplastic fibroblastoma (collagenous fibroma) is a rare soft tissue tumor that usually arises in the subcutis or skeletal muscle. Cases superficial to fascia are unusual and can cause diagnostic difficulty. We present 11 cases of superficial desmoplastic fibroblastoma involving a wide anatomic distribution., Methods: Archives were searched using the term "desmoplastic fibroblastoma" over a 10-year period (2012-2022). Cases superficial to fascia were retrieved, and available clinicopathologic features were recorded. Only cases involving the dermis were included., Results: Eleven cases were identified, all of which were received in consultation. Tumors involved the head and neck (2), lower extremity (2), back (2), foot (1), shoulder (1), axilla (1), hand (1), and breast (1). Each consisted of a hypocellular proliferation of bland stellate to spindled fibroblasts set in a collagenous to focally myxoid stroma. The immunohistochemical stains available for review demonstrated SMA positivity (4/7) and negative immunoreactivity for CD34 (0/6), EMA (0/3), desmin (0/3), and S100 (0/7)., Conclusions: Desmoplastic fibroblastoma may present superficially in the dermis to subcutis, posing a potential source of diagnostic difficulty. Recognition of the characteristic histopathologic features of desmoplastic fibroblastoma with judicial use of immunohistochemical stains should allow for accurate diagnosis., (© 2023 The Authors. Journal of Cutaneous Pathology published by John Wiley & Sons Ltd.)

Basal cell carcinoma (BCC), one of the most common malignancies, is rarely associated with follicular and apocrine differentiation patterns. This case presents a case of BCC with atypical gross presentation and features of aberrant differentiation. Clinicians should maintain a high level of clinical suspicion for BCC in atypical lesions. Click here for the corresponding questions to this CME article., (© 2022 British Association of Dermatologists.)

Objective . Electrical stimulation of the retina can elicit flashes of light called phosphenes, which can be used to restore rudimentary vision for people with blindness. Functional sight requires stimulation of multiple electrodes to create patterned vision, but phosphenes tend to merge together in an uninterpretable way. Sequentially stimulating electrodes in human visual cortex has recently demonstrated that shapes could be 'drawn' with better perceptual resolution relative to simultaneous stimulation. The goal of this study was to evaluate if sequential stimulation would also form clearer shapes when the retina is the neural target. Approach . Two human participants with retinitis pigmentosa who had Argus ® II epiretinal prostheses participated in this study. We evaluated different temporal parameters for sequential stimulation and performed phosphene shape mapping and forced choice discrimination tasks. For the discrimination tasks, performance was compared between stimulating electrodes simultaneously versus sequentially. Main results . Phosphenes elicited by different electrodes were reported as vastly different shapes. For sequential stimulation, the optimal pulse train duration was 200 ms when stimulating at 20 Hz and the optimal gap interval was tied between 0 and 50 ms. Sequential electrode stimulation outperformed simultaneous stimulation in simple discrimination tasks, in which shapes were created by stimulating 3-4 electrodes, but not in more complex discrimination tasks involving ≥5 electrodes. The efficacy of sequential stimulation depended strongly on selecting electrodes that elicited phosphenes with similar shapes and sizes. Significance . An epiretinal prosthesis can produce coherent simple shapes with a sequential stimulation paradigm, which can be used as rudimentary visual feedback. However, success in creating more complex shapes, such as letters of the alphabet, is still limited. Sequential stimulation may be most beneficial for epiretinal prostheses in simple tasks, such as basic navigation, rather than complex tasks such as novel object identification., (Creative Commons Attribution license.)

Background: The Model for End-Stage Liver Disease (MELD) score was originally described as a marker of survival in chronic liver disease. More recently, MELD and its derivatives, MELD excluding INR (MELD-XI) and MELD with sodium (MELD-Na), have been applied more broadly as outcome predictors in heart transplant, left ventricular assist device placement, heart failure, and cardiogenic shock, with additional promising data to support the use of these scores for prediction of survival in those undergoing veno-arterial extracorporeal membrane oxygenation (VA ECMO)., Methods: This study assessed the prognostic impact of MELD in patients with cardiogenic shock undergoing VA ECMO via a single-center retrospective review from January 2014 to March 2020. MELD, MELD-XI, and MELD-Na scores were calculated using laboratory values collected within 48 h of VA ECMO initiation. Multivariate Cox regression analyses determined the association between MELD scores and the primary outcome of 90-day mortality. Receiver operating characteristics (ROC) were used to estimate the discriminatory power for MELD in comparison with previously validated SAVE score., Results: Of the 194 patients, median MELD was 20.1 (13.7-26.2), and 90-day mortality was 62.1%. There was a significant association between MELD score and mortality up to 90 days (hazard ratio (HR) = 1.945, 95% confidence interval (95% CI) = 1.244-3.041, p = 0.004) after adjustment for age, indication for VA ECMO, and sex. The prognostic significance of MELD score for 90-day mortality revealed an AUC of 0.645 (95% CI = 0.565-0.725, p < 0.001). MELD-Na score and MELD-XI score were not associated with mortality., Conclusion: MELD score accurately predicts long-term mortality and may be utilized as a valuable decision-making tool in patients undergoing VA ECMO.