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Background: Gastrointestinal (GI) disorders like chronic constipation are more prevalent with aging. Aging GI tract becomes stiffer and exhibits delayed GI transit. Smooth muscle cells (SMCs) are involved in controlling GI transit and show reduced contractility with age. Piezo1 is a mechanically activated ion channel that responds to membrane tension by opening its pore to allow flow of ions such as calcium (Ca2+) and regulates various cellular processes through Ca2+-calcineurin signaling pathway. We wondered GI stiffness changes might control SMC contractile to non-contractile phenotype through Piezo1. Objective: To determine how substrate stiffness regulates GI SMC contractile phenotype through Piezo1. Hypothesis: SMC Piezo1 senses GI tissue stiffness changes and alters SMC phenotype. Methods: Pathway analysis on human colon single cell sequencing data was performed using Gene Set Enrichment Analysis (GSEA) pre-ranked module with publicly available gene-sets from Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Immortalized human jejunal SMCs (HuSMCs) and freshly dissociated SMCs from control (CTRL, Myh11-creERT2) and SMC specific Piezo1 knockout [Myh11-creERT2xPiezo1 Flox (Piezo1-KO)] mouse colons (primary SMCs) were cultured on soft (1kPa) and stiff (50kPa) substrates to model age-dependent shifts in intestinal stiffness for 48 hours either in the presence/absence of Piezo1 siRNA, Piezo1 agonist (Yoda1, 1μM), and calcineurin blocker (Cyclosporin A, CsA, 1μM) and used for Ca2+ imaging, RT-qPCR and immunostaining. Results: GSEA showed Piezo1+ve SMCs were significantly enriched in pathways involved in the regulation of Ca2+ signaling compared to Piezo1−ve SMCs (p<0.05). HuSMCs and primary SMCs showed increased Piezo1 expression (HuSMCs:1.1±0.2-fold, n=8, p<0.05; primary SMCs:2.1±0.1-fold, n=3, p<0.05) and cytoplasmic Ca2+ (3.6-fold, n=10, p<0.05) in response to Yoda1 on stiff substrates compared to soft. HuSMCs on stiff substrate showed decreased expression of contractile SMC markers smoothelin ( SMTN:0.7±0.2-fold, n=7, p<0.05) and transgelin ( TAGLN:0.6±0.1-fold, n=7, p<0.05) which was rescued by Piezo1 siRNA treatment ( SMTN:1.2±0.1-fold, n=2-7, p<0.05; TAGLN:1.15±0.02-fold, n=2-7, p<0.05) (Piezo1 is necessary). Stimulation by Yoda1 of HuSMCs on the soft substrate resulted in decreased expression of SMTN (0.7±0.3-fold, n=2-7, p<0.05) and TAGLN (0.7±0.1-fold, n=2-7, p<0.05) (Piezo1 is suffcient). CTRL primary SMCs on stiff substrate showed decreased expression of Smtn (0.4±0.1-fold, n=3, p<0.05) and Tagln (0.3±0.2-fold, n=3, p<0.05) compared to SMCs on soft substrate which was reversed when SMCs from Piezo1-KO mice were cultured on these substrates ( Smtn:1.8±0.5-fold, n=3, p<0.05; Tagln:2.4±0.07-fold, n=3, p<0.05). Treatment of CsA in HuSMCs cultured on stiff substrate also rescued from loss of SMTN (1.3±0.1-fold, n=3, p<0.05) and TAGLN (1.7±0.3-fold, n=3, p<0.05) expression and prevented nuclear factor of activated T cells (NFAT) nuclear translocation. Summary and Conclusion: GI SMC Piezo1 senses stiffness changes and regulates SMC phenotype through Ca2+-calcineurin signaling pathway. Targeting Piezo1 might be protective from age induced reduced GI SMC contractility. NIH DK052766, DK123549. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

AbstractBackgroundDespite the overall safety and efficacy of COVID‐19 vaccinations, rare cases of systemic autoimmune diseases (SAIDs) have been reported post‐vaccination. This study used a global survey to analyze SAIDs in susceptible individuals' post‐vaccination.MethodsA cross‐sectional study was conducted among participants with self‐reported new‐onset SAIDs using the COVID‐19 Vaccination in Autoimmune Diseases (COVAD) 2 study dataset—a validated, patient‐reported e‐survey—to analyze the long‐term safety of COVID‐19 vaccines. Baseline characteristics of patients with new‐onset SAIDs and vaccinated healthy controls (HCs) were compared after propensity score matching based on age and sex in a 1:4 ratio.ResultsOf 16 750 individuals, 74 (median age 52 years, 79.9% females, and 76.7% Caucasians) had new‐onset SAID post‐vaccination, mainly idiopathic inflammatory myopathies (IIMs) (n = 23, 31.51%), arthritis (n = 15; 20.53%), and polymyalgia rheumatica (PMR) (n = 12, 16.40%). Higher odds of new‐onset SAIDs were noted among Caucasians (OR = 5.3; 95% CI = 2.9–9.7; p < .001) and Moderna vaccine recipients (OR = 2.7; 95% CI = 1.3–5.3; p = .004). New‐onset SAIDs were associated with AID multimorbidity (OR = 1.4; 95% CI = 1.1–1.7; p < .001), mental health disorders (OR = 1.6; 95% CI = 1.3–1.9; p < .001), and mixed race (OR = 2.2; 95% CI = 1.2–4.2; p = .010), where those aged >60 years (OR = 0.6; 95% CI = 0.4–0.8; p = .007) and from high/medium human development index (HDI) countries (compared to very high HDI) reported fewer events than HCs.ConclusionThis study reports a low occurrence of new‐onset SAIDs following COVID‐19 vaccination, primarily IIMs, PMR, and inflammatory arthritis. Identified risk factors included pre‐existing AID multimorbidity, mental health diseases, and mixed race. Revaccination was well tolerated by most patients; therefore, we recommend continuing COVID‐19 vaccination in the general population. However, long‐term studies are needed to understand the autoimmune phenomena arising post‐vaccination.

AbstractBackgroundThe pandemic presented unique challenges for individuals with autoimmune and rheumatic diseases (AIRDs) due to their underlying condition, the effects of immunosuppressive treatments, and increased vaccine hesitancy.ObjectivesThe COVID‐19 vaccination in autoimmune diseases (COVAD) study, a series of ongoing, patient self‐reported surveys were conceived with the vision of being a unique tool to gather patient perspectives on AIRDs. It involved a multinational, multicenter collaborative effort amidst a global lockdown.MethodsLeveraging social media as a research tool, COVAD collected data using validated patient‐reported outcomes (PROs). The study, comprising a core team, steering committee, and global collaborators, facilitated data collection and analysis. A pilot‐tested, validated survey, featuring questions regarding COVID‐19 infection, vaccination and outcomes, patient demographics, and PROs was circulated to patients with AIRDs and healthy controls (HCs).DiscussionWe present the challenges encountered during this international collaborative project, including coordination, data management, funding constraints, language barriers, and authorship concerns, while highlighting the measures taken to address them.ConclusionCollaborative virtual models offer a dynamic new frontier in medical research and are vital to studying rare diseases. The COVAD study demonstrates the potential of online platforms for conducting large‐scale, patient‐focused research and underscores the importance of integrating patient perspective into clinical care. Care of patients is our central motivation, and it is essential to recognize their voices as equal stakeholders and valued partners in the study of the conditions that affect them.

BACKGROUND Diagnosis of PMM2-CDG, the most common congenital disorder of glycosylation (CDG), relies on measuring carbohydrate-deficient transferrin (CDT) and genetic testing. CDT tests have false negatives and may normalize with age. Site-specific changes in protein N-glycosylation have not been reported in sera in PMM2-CDG. METHODS Using multistep mass spectrometry–based N-glycoproteomics, we analyzed sera from 72 individuals to discover and validate glycopeptide alterations. We performed comprehensive tandem mass tag–based discovery experiments in well-characterized patients and controls. Next, we developed a method for rapid profiling of additional samples. Finally, targeted mass spectrometry was used for validation in an independent set of samples in a blinded fashion. RESULTS Of the 3,342 N-glycopeptides identified, patients exhibited decrease in complex-type N-glycans and increase in truncated, mannose-rich, and hybrid species. We identified a glycopeptide from complement C4 carrying the glycan Man 5 GlcNAc 2 , which was not detected in controls, in 5 patients with normal CDT results, including 1 after liver transplant and 2 with a known genetic variant associated with mild disease, indicating greater sensitivity than CDT. It was detected by targeted analysis in 2 individuals with variants of uncertain significance in PMM2 . CONCLUSION Complement C4–derived Man 5 GlcNAc 2 glycopeptide could be a biomarker for accurate diagnosis and therapeutic monitoring of patients with PMM2-CDG and other CDGs. FUNDING U54NS115198 (Frontiers in Congenital Disorders of Glycosylation: NINDS; NCATS; Eunice Kennedy Shriver NICHD; Rare Disorders Consortium Disease Network); K08NS118119 (NINDS); Minnesota Partnership for Biotechnology and Medical Genomics; Rocket Fund; R01DK099551 (NIDDK); Mayo Clinic DERIVE Office; Mayo Clinic Center for Biomedical Discovery; IA/CRC/20/1/600002 (Center for Rare Disease Diagnosis, Research and Training; DBT/Wellcome Trust India Alliance)

ObjectiveIn 2020, one study by Strait and colleagues raised awareness that the clinical images in rheumatology educational materials underrepresent people with skin of color (P‐SOC). Since then, publishers of rheumatology educational materials have focused on addressing this shortcoming. This study investigates the change in representation of P‐SOC following the review of Strait et al.MethodsWe used the methods of the aforementioned study to collect images from commonly referenced rheumatology educational materials and categorized the skin tones within them as “light” or “dark.” We calculated the proportional change in images depicting dark skin tones between 2020 and 2022 from the American College of Rheumatology (ACR) Image Library, the 10th edition of Kelley's Textbook of Rheumatology, and New England Journal of Medicine (NEJM) as well as between 2020 and 2024 from rheumatology articles within UpToDate. We compared results using one‐sided Z‐tests.ResultsOverall, the proportion of images depicting dark skin tones increased 40.6% (P < 0.0001). The 10th edition of Kelley's Textbook of Rheumatology most significantly increased inclusion of P‐SOC (90.1%; P = 0.0039), with ACR Image Library, UpToDate, and NEJM also enhancing representation (41.9%, P < 0.0001; 31.0%, P = 0.0083; 28.2%, P = 0.3046, respectively).ConclusionThis study assesses the progress of rheumatology educational materials toward equitable representation of P‐SOC. It demonstrates that awareness coupled with focused efforts from educational publishers can enhance the proportion of images depicting dark skin tones, thereby enriching the quality of foundational knowledge relayed to rheumatology providers with the goal of improving health experiences and outcomes for P‐SOC with rheumatic diseases.image

AbstractAsparagine‐linked glycosylation 1 protein is a β‐1,4‐mannosyltransferase, is encoded by the ALG1 gene, which catalyzes the first step of mannosylation in N‐glycosylation. Pathogenic variants in ALG1 cause a rare autosomal recessive disorder termed as ALG1‐CDG. We performed a quantitative proteomics and N‐glycoproteomics study in fibroblasts derived from patients with one homozygous and two compound heterozygous pathogenic variants in ALG1. Several proteins that exhibited significant upregulation included insulin‐like growth factor II and pleckstrin, whereas hyaluronan and proteoglycan link protein 1 was downregulated. These proteins are crucial for cell growth, survival and differentiation. Additionally, we observed a decrease in the expression of mitochondrial proteins and an increase in autophagy‐related proteins, suggesting mitochondrial and cellular stress. N‐glycoproteomics revealed the reduction in high‐mannose and complex/hybrid glycopeptides derived from numerous proteins in patients explaining that defect in ALG1 has broad effects on glycosylation. Further, we detected an increase in several short oligosaccharides, including chitobiose (HexNAc2) trisaccharides (Hex‐HexNAc2) and novel tetrasaccharides (NeuAc‐Hex‐HexNAc2) derived from essential proteins including LAMP1, CD44 and integrin. These changes in glycosylation were observed in all patients irrespective of their gene variants. Overall, our findings not only provide novel molecular insights into understanding ALG1‐CDG but also offer short oligosaccharide‐bearing peptides as potential biomarkers.

Abstract Objectives The objective of this study was to explore the prevalence, characteristics and risk factors of COVID-19 breakthrough infections (BIs) in idiopathic inflammatory myopathies (IIMs) using data from the COVID-19 Vaccination in Autoimmune Diseases (COVAD) study. Methods A validated patient self-reporting e-survey was circulated by the COVAD study group to collect data on COVID-19 infection and vaccination in 2022. BIs were defined as COVID-19 occurring ≥14 days after two vaccine doses. We compared BI characteristics and severity among patients with IIMs, patients with other autoimmune rheumatic and non-rheumatic diseases (AIRD, nrAID), and healthy controls (HCs). Multivariable Cox regression models were used to assess the risk factors for BI, severe BI ,and hospitalizations among patients with IIMs. Results Among the 9449 included responses, BIs occurred in 1447 respondents (15.3%). The median age was 44 years [interquartile range (IQR) 21], 77.4% were female, and 182 BIs (12.9%) occurred among the 1406 patients with IIMs. Multivariable Cox regression among the data for patients with IIMs showed increasing age to be a protective factor for BIs [hazard ratio (HR) = 0.98, 95% CI = 0.97–0.99], and HCQ and SSZ use were risk factors (HR = 1.81, 95% CI = 1.24–2.64, and HR = 3.79, 95% CI = 1.69–8.42, respectively). Glucocorticoid use was a risk factor for a severe BI (HR = 3.61, 95% CI = 1.09–11.8). Non-white ethnicity (HR = 2.61, 95% CI = 1.03–6.59) was a risk factor for hospitalization. Compared with other groups, patients with IIMs required more supplemental oxygen therapy (IIMs = 6.0% vs AIRDs = 1.8%, nrAIDs = 2.2% and HCs = 0.9%), intensive care unit admission (IIMs = 2.2% vs AIRDs = 0.6%, nrAIDs and HCs = 0%), advanced treatment with antiviral or monoclonal antibodies (IIMs = 34.1% vs AIRDs = 25.8%, nrAIDs = 14.6% and HCs = 12.8%) and had more hospitalization (IIMs = 7.7% vs AIRDs = 4.6%, nrAIDs = 1.1% and HCs = 1.5%). Conclusion Patients with IIMs are susceptible to severe COVID-19 BIs. Age and immunosuppressive treatments were related to the risk of BIs.

Background: Homelessness is a growing concern in the US, with 3.5 million people experiencing it annually and 600,000 on any given night. Homeless individuals face increased vulnerability to 30-day hospital readmissions and higher mortality rates, straining the healthcare system and exacerbating existing disparities. This study aims to inform neurosurgeons on evidence-based strategies to reduce readmission and mortality rates among homeless patients by reviewing the literature on the impact of medical respite on 30-day readmission rates. The study aims to gauge the efficacy of medical respite in reducing hospital readmissions and improving health outcomes for homeless individuals. Methods: A comprehensive literature search was conducted across PubMed, Embase/Medline, and Cochrane databases, as well as consulting the National Institute for Medical Respite Care and the Department of Health Care Access and Information. Ten articles were chosen from an initial 296 to investigate the impact of respite programs on readmission rates among homeless patients. Results: Homeless patients experience high readmission rates due to various factors. Interventions such as respite programs and a comprehensive approach to healthcare can lower these rates. Collaboration between hospitals and medical respites has proven particularly effective. Conclusion: Inadequate healthcare for homeless individuals leads to increased readmissions, longer hospital stays, and higher costs. Medical respites are a viable solution, but limited resources hamper their effectiveness. Therefore, it is crucial to facilitate cooperation between hospitals, respites, and other entities. Future research should focus on disparity in neurosurgical procedures and explore alternative services. An interdisciplinary approach is key to addressing healthcare inequalities.

AbstractBackgroundKetamine is increasingly used for treatment‐resistant depression (TRD) while its mechanism of action is still being investigated. In this systematic review, we appraise the current evidence of metabolomic biomarkers for racemic ketamine and esketamine in patients with TRD and healthy controls (HCs).MethodsA comprehensive search of several databases (Ovid MEDLINE®, Embase, and Epub Ahead of Print) was performed from each database's inception to June 29, 2022, in any language, was conducted. We included studies wherein the metabolomic biomarkers for racemic ketamine or esketamine were investigated in TRD or HCs. Our main outcomes were to examine changes in metabolites among patients treated with ketamine/esketamine and explore the association with response to ketamine/esketamine.ResultsA total of 1859 abstracts were screened of which 11 were included for full‐text review. Of these, a total of five articles were included (N = 147), including three RCTs (n = 129) and two open‐label trials (n = 18). All studies used racemic ketamine; one study additionally used esketamine. The included studies evaluated patients with treatment‐resistant bipolar depression (n = 22), unipolar depression (n = 91), and HCs (n = 34). The included studies reported alteration in several metabolites including acylcarnitines, lipids, kynurenine (KYN), and arginine with ketamine in TRD. Studies suggest the involvement of energy metabolism, KYN, and arginine pathways. In HCs, acetylcarnitine decreased post‐infusion, whereas inconsistent findings were observed after the ketamine infusion in TRD patients.ConclusionsThis systematic review provides preliminary evidence that ketamine may cause changes in several important pathways involved in energy metabolism and inflammation. Larger and more rigorous studies are needed.