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BACKGROUND: Continuous-flow left ventricular assist device (cfLVAD) use is effective in supporting patients with end-stage heart failure (ESHF). Reduced flow pulsatility within the systemic circulation in cfLVAD-supported patients may lead to alterations within the microcirculation. Temporal changes in microvasculature in relation to adverse events in cfLVAD-supported patients have not been studied. We aimed to profile changes within retinal microvasculature and its association with adverse events. METHODS: Retinal photography was performed using Topcon TRC-NW8 nonmydriatic fundus camera in cfLVAD-supported patients and ESHF control patients. Specific retinal measurements were evaluated using a validated semiautomated program. Demographic and adverse event data were documented. RESULTS: Forty-eight patients were studied (n = 29 cfLVAD, n = 19 ESHF). There were significant trends in retinal arteriolar caliber (B = -0.53 µm, 95% confidence interval [CI]: -0.96 to -0.10, p = 0.016) and retinal fractal dimension parameters (B = 0.014, 95% CI: 0.001-0.002, p = 0.016) in linear mixed model regressions. Among cfLVAD patients, there was a significant association between the incidence of gastrointestinal bleeding and stepwise increases in retinal arteriolar-venular caliber ratio (hazard ratio: 3.03, 95% CI: 2.06-4.45, p = 0.005), a measure of arteriolar narrowing. CONCLUSIONS: We have observed for the first time that alterations in retinal microvasculature in cfLVAD-supported patients may be associated with gastrointestinal bleeding. While understanding these temporal changes may predict future adverse events in cfLVAD-supported patients, further multicenter studies are required to confirm the associations observed.
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Epidemiological evidence suggests the potential for air pollutants to induce male reproductive toxicity. In experimental studies, exposure to ozone during sensitive windows in the sperm lifecycle has been associated with impaired sperm motility. Subsequently, we sought to investigate the effects of episodic exposure to ozone during sperm maturation in the rat. Long-Evans rats were exposed to either filtered air or ozone (0.4 or 0.8â¯ppm) for five non-consecutive days over two weeks. Ozone exposure did not impact male reproductive organ weights or sperm motility â¼24â¯hours following the final exposure. Furthermore, circulating sex hormones remained unchanged despite increased T3 and T4 in the 0.8â¯ppm group. While there was indication of altered adrenergic signaling attributable to ozone exposure in the testis, there were minimal impacts on small non-coding RNAs detected in cauda sperm. Only two piwi-interacting RNAs (piRNAs) were altered in the mature sperm of ozone-exposed rats (piR-rno-346434 and piR-rno-227431). Data across all rats were next analyzed to identify any non-coding RNAs that may be correlated with reduced sperm motility. A total of 7 microRNAs (miRNAs), 8 RNA fragments, and 1682 piRNAs correlated well with sperm motility. Utilizing our exposure paradigm herein, we were unable to substantiate the relationship between ozone exposure during maturation with sperm motility. However, these approaches served to identify a suite of non-coding RNAs that were associated with sperm motility in rats. With additional investigation, these RNAs may prove to have functional roles in the acquisition of motility or be unique biomarkers for male reproductive toxicity.
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This study investigates the characteristics of cardiac mesenchymal stem cell-like cells (CMSCLCs) isolated from the right atrial appendage of human donors with ischemia and a young patient with endocarditis (NE-CMSCLCs). Typical CMSCLCs from ischemic heart patients were derived from coronary artery bypass grafting procedures and compared against bone marrow mesenchymal stromal cells (BM-MSCs). NE-CMSCLCs had a normal immunophenotype, but exhibited enhanced osteogenic differentiation potential, rapid proliferation, reduced senescence, reduced glycolysis, and lower reactive oxygen species generation after oxidative stress compared with typical ischemic CMSCLCs. These differences suggest a unique functional status of NE-CMSCLCs, influenced by the donor health condition. Despite large variances in their paracrine secretome, NE-CMSCLCs retained therapeutic potential, as indicated by their ability to protect hypoxia/reoxygenation-injured human cardiomyocytes, albeit less effectively than typical CMSCLCs. This research describes a unique cell phenotype and underscores the importance of donor health status in the therapeutic efficacy of autologous cardiac cell therapy.
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Immobilisation masks (IMs) are used for people with head and neck cancer (HNC) undergoing radiation therapy (RT) treatment to ensure accuracy and reproducibility between treatments. Claustrophobia-related mask anxiety in HNC patients is common and can compromise treatment due to patient distress. This scoping review aimed to describe the content of publicly available Patient Education Materials (PEMs) for people with HNC undergoing RT. Three search engines (Bing, Yahoo, and Google) were systematically searched using standard terms. PEMs in audio-visual or written formats were eligible for inclusion if the target readership was adults with HNC and included content on IMs for RT. Content was appraised using the Patient Education Materials Assessment Tool for Printable and Audio-Visual Materials to assess understandability and actionability. In total, 304 PEMs were identified of which 20 met the inclusion criteria. Sixteen PEMs were webpages, three were PDF format, and one was a standalone video. The understandability and actionability of PEMs ranged between 47 to 100% and 0 to 80%, respectively. PEMs authored by Foundations/Organisations scored higher in understandability (80-100%) and were more likely to discuss mask anxiety coping strategies. In comparison, News sites and IM manufacturers published PEMs with the lowest understandability scores (20-80%). The significant variations in the quality of IM PEMs identified suggest that some sources may be more effective at informing patients about IMs. Although multiple aspects of the PEMs were consistent across the reviewed materials, many PEMs lacked information, and a stronger focus on understandability and actionability is required.
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Exposure to wildfire smoke is associated with both acute and chronic cardiopulmonary illnesses, which are of special concern for wildland firefighters who experience repeated exposure to wood smoke. It is necessary to better understand the underlying pathophysiology by which wood smoke exposure increases pulmonary disease burdens in this population. We hypothesize that wood smoke exposure produces pulmonary dysfunction, lung inflammation, and gene expression profiles associated with future pulmonary complications. Male Long-Evans rats were intermittently exposed to smoldering eucalyptus wood smoke at 2 concentrations, low (11.0 ± 1.89 mg/m3) and high (23.7 ± 0.077 mg/m3), over a 2-week period. Whole-body plethysmography was measured intermittently throughout. Lung tissue and lavage fluid were collected 24 h after the final exposure for transcriptomics and metabolomics. Increasing smoke exposure upregulated neutrophils and select cytokines in the bronchoalveolar lavage fluid. In total, 3446 genes were differentially expressed in the lungs of rats in the high smoke exposure and only 1 gene in the low smoke exposure (Cd151). Genes altered in the high smoke group reflected changes to the Eukaryotic Initiation Factor 2 stress and oxidative stress responses, which mirrored metabolomics analyses. xMWAS-integrated analysis revealed that smoke exposure significantly altered pathways associated with oxidative stress, lung morphogenesis, and tumor proliferation pathways. These results indicate that intermittent, 2-week exposure to eucalyptus wood smoke leads to transcriptomic and metabolic changes in the lung that may predict future lung disease development. Collectively, these findings provide insight into cellular signaling pathways that may contribute to the chronic pulmonary conditions observed in wildland firefighters.
Subject(s)
Eucalyptus , Lung , Rats, Long-Evans , Smoke , Animals , Male , Smoke/adverse effects , Lung/drug effects , Lung/metabolism , Wood , Rats , Bronchoalveolar Lavage Fluid/chemistry , Metabolome/drug effects , Transcriptome/drug effects , Inhalation Exposure/adverse effects , Cytokines/metabolism , Cytokines/geneticsABSTRACT
PURPOSE: To evaluate the association between social determinants of health (SDH) with presentation and outcomes in patients with ocular cancer. METHODS: The National Cancer Database was queried for primary clinical tumor (cT) classifications of T1 to T4 N0M0 uveal melanoma, conjunctival melanoma, or retinoblastoma diagnosed between January 2006 and December 2017. Pearson χ2 analysis assessed differences in SDH-related characteristics between cancer cohorts. Binary logistic regression with adjusted odds ratios (aORs) and multivariate Cox proportional hazards ratios (HRs) with 95% confidence intervals (CIs) were performed. DESIGN: Cross-sectional with a nationally representative sample. RESULTS: Three thousand nine hundred sixty-eight uveal melanoma cases, 352 conjunctival melanoma cases, and 480 retinoblastoma cases were included. Differences in race, primary payer status, income quartile, population density, facility location, Charlson-Deyo comorbidity score, history of malignancy, cT classification at presentation, surgical treatment, radiotherapy, chemotherapy, 30-day readmission, and overall survival (OS) were observed among the cancers. Female sex (aOR 0.819 [95% CI 0.689-0.973]) and top income quartile (aOR 0.691 [95% CI 0.525-0.908]) had decreased likelihood of advanced cT classification at presentation. No insurance (aOR 1.736 [95% CI 1.159-2.601]) and Medicaid primary payer status (aOR 1.875 [95% CI 1.323-2.656]) had increased likelihood of advanced cT classification. Patients in rural areas (aOR 7.157 [95% CI 1.875-27.320]) were more likely to be readmitted within 30 days after initial treatment. Increased age was associated with decreased 5-year OS (HR 1.040 [95% CI 1.033-1.047]). CONCLUSIONS: SDH may influence advanced cT classification at presentation and 30-day readmission compared with OS in patients with ocular cancer, highlighting the need for ophthalmologists and public health efforts to address disparities in SDH.
Subject(s)
Melanoma , Retinal Neoplasms , Retinoblastoma , Uveal Neoplasms , United States/epidemiology , Humans , Female , Melanoma/therapy , Patient Readmission , Retinoblastoma/therapy , Social Determinants of Health , Cross-Sectional Studies , Retinal Neoplasms/therapy , Retrospective StudiesABSTRACT
PURPOSE: Women are underrepresented in several medical specialties, including ophthalmology. Reducing disparities is critical in diversifying perspectives and increasing equity within ophthalmology, both of which can ultimately improve care delivery. We examined ophthalmic fellowship programs directors in the United States to investigate gender disparities by subspecialty. DESIGN: Cross-sectional study. METHODS: This was a retrospective cross-sectional study of ophthalmology fellowship program directors in academic medical centers. The primary outcome measure was a descriptive analysis of current fellowship directors in 2022 when stratified by subspecialty and demographic features. RESULTS: Analysis was conducted on 358 fellowship directors in the United States. Twenty-nine percent of directors were women. Female directors had significantly fewer years since residency graduation compared with male peers (17 vs 24; P < .001); however, no differences were observed by program type (P = .896) or location (P = 0.104). Differences in female director representation were observed by subspecialty (P < .001), with the greatest percentage of women in pediatric ophthalmology (54%), other (oncology and pathology) fellowships (50%), and medical retina (40%). The subspecialties with the lowest percentage of female directors were oculoplastic and reconstructive surgery (13%) surgical retina and vitreous (16%). CONCLUSION: There are disparities in female representation in academic leadership positions across ophthalmic subspecialties. Addressing this difference may have critical impacts on career advancement and opportunities available for marginalized groups in medicine.
Subject(s)
Internship and Residency , Ophthalmology , Child , Humans , Male , Female , United States , Fellowships and Scholarships , Ophthalmology/education , Cross-Sectional Studies , Retrospective Studies , Faculty, MedicalABSTRACT
Aging is associated with immunological changes that compromise response to infections and vaccines, exacerbate inflammatory diseases and can potentially mitigate tissue repair. Even so, age-related changes to the immune response to tissue damage and regenerative medicine therapies remain unknown. Here, it is characterized how aging induces changes in immunological signatures that inhibit tissue repair and therapeutic response to a clinical regenerative biological scaffold derived from extracellular matrix. Signatures of inflammation and interleukin (IL)-17 signaling increased with injury and treatment both locally and regionally in aged animals, and computational analysis uncovered age-associated senescent-T cell communication that promotes type 3 immunity in T cells. Local inhibition of type 3 immune activation using IL17-neutralizing antibodies improves healing and restores therapeutic response to the regenerative biomaterial, promoting muscle repair in older animals. These results provide insights into tissue immune dysregulation that occurs with aging that can be targeted to rejuvenate repair.
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OBJECTIVES: To systematically investigate the associations between vision impairment and risk of motor vehicle crash (MVC) involvement, and evaluate vision-related interventions to reduce MVCs. DESIGN: Medline (Ovid), EMBASE and Global Health electronic databases were systematically searched from inception to March 2022 for observational and interventional English-language studies. Screening, data extraction and appraisals using the Joanna Briggs Institute appraisal tools were completed by two reviewers independently. Where appropriate, measures of association were converted into risk ratios (RRs) or ORs for meta-analysis. PARTICIPANTS: Drivers of four-wheeled vehicles of all ages with no cognitive declines. PRIMARY AND SECONDARY OUTCOMES: MVC involvement (primary) and driving cessation (secondary). RESULTS: 101 studies (n=778 052) were included after full-text review. 57 studies only involved older drivers (≥65 years) and 85 were in high-income settings. Heterogeneity in the data meant that most meta-analyses were underpowered as only 25 studies, further split into different groups of eye diseases and measures of vision, could be meta-analysed. The limited evidence from the meta-analyses suggests that visual field defects (four studies; RR 1.51 (95% CI 1.23, 1.85); p<0.001; I2=46.79%), and contrast sensitivity (two studies; RR 1.40 (95% CI 1.08, 1.80); p=0.01, I2=0.11%) and visual acuity loss (five studies; RR 1.21 (95% CI 1.02, 1.43); p=0.03, I2=28.49%) may increase crash risk. The results are more inconclusive for available evidence for associations of glaucoma (five studies, RR 1.27 (95% CI 0.67, 2.42); p=0.47; I2=93.48%) and cataract (two studies RR 1.15 (95% CI 0.97, 1.36); p=0.11; I2=3.96%) with crashes. Driving cessation may also be linked with glaucoma (two studies; RR 1.62 (95% CI 1.20, 2.19); p<0.001, I2=22.45%), age-related macular degeneration (AMD) (three studies; RR 2.21 (95% CI 1.47, 3.31); p<0.001, I2=75.11%) and reduced contrast sensitivity (three studies; RR 1.30 (95% CI 1.05, 1.61); p=0.02; I2=63.19%). Cataract surgery halved MVC risk (three studies; RR 0.55 (95% CI 0.34, 0.92); p=0.02; I2=97.10). Ranibizumab injections (four randomised controlled trials) prolonged driving in persons with AMD. CONCLUSION: Impaired vision identified through a variety of measures is associated with both increased MVC involvement and cessation. Cataract surgery can reduce MVC risk. Despite literature being highly heterogeneous, this review shows that detection of vision problems and appropriate treatment are critical to road safety. PROSPERO REGISTRATION NUMBER: CRD42020172153.
Subject(s)
Cataract , Macular Degeneration , Humans , Visual Acuity , Ranibizumab , Accidents, Traffic/prevention & control , Macular Degeneration/epidemiology , Vision Disorders/epidemiology , Cataract/complicationsABSTRACT
INTRODUCTION: The aim of this study was to determine the prevalence of diabetic retinopathy (DR) in a low socioeconomic region of a high-income country, as well as determine the diagnostic utility of point-of-care screening for high-risk populations in tertiary care settings. RESEARCH DESIGN AND METHODS: This was a cross-sectional study of patients with diabetes attending foot ulcer or integrated care diabetes clinics at two Western Sydney hospitals (n=273). DR was assessed using portable, two-field, non-mydriatic fundus photography and combined electroretinogram/ pupillometry (ERG). With mydriatic photographs used as the reference standard, sensitivity and specificity of the devices were determined. Prevalence of DR and vision-threatening diabetic retinopathy (VTDR) were reported, with multivariate logistic regression used to identify predictors of DR. RESULTS: Among 273 patients, 39.6% had any DR, while 15.8% had VTDR, of whom 59.3% and 62.8% were previously undiagnosed, respectively. Non-mydriatic photography demonstrated 20.2% sensitivity and 99.5% specificity for any DR, with a 56.7% screening failure rate. Meanwhile, mydriatic photography produced high-quality images with a 7.6% failure rate. ERG demonstrated 72.5% sensitivity and 70.1% specificity, with a 15.0% failure rate. The RETeval ERG was noted to have an optimal DR cut-off score at 22. Multivariate logistic regression identified an eGFR of ≤29 mL/min/1.73 m2, HbA1c of ≥7.0%, pupil size of <4 mm diameter, diabetes duration of 5-24 years and RETeval score of ≥22 as strong predictors of DR. CONCLUSION: There is a high prevalence of vision-threatening and undiagnosed DR among patients attending high-risk tertiary clinics in Western Sydney. Point-of-care DR screening using portable, mydriatic photography demonstrates potential as a model of care which is easily accessible, targeted for high-risk populations and substantially enhances DR detection.
Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Humans , Diabetic Retinopathy/diagnosis , Diabetic Retinopathy/epidemiology , Point-of-Care Systems , Cross-Sectional Studies , Mass Screening/methods , Sensitivity and Specificity , MydriaticsABSTRACT
OBJECTIVES: To report the 15-year incidence of driving cessation and its associated vision-related risk factors in an older Australian population-based cohort. STUDY DESIGN: 15-year data from a sample of 2379 participants who indicated that they were driving at baseline from The Blue Mountains Eye Study was analysed. Questions about driving cessation was asked at all four visits and was recorded as a binary response (Yes/No). Clinical vision examinations were performed at each visit to determine presenting and best-corrected visual acuity and any incident eye diseases (Yes/No). MAIN OUTCOME MEASURES: The cumulative 15-year incidence of driving cessation was calculated using interval-censored data progression-free survival analyses. Age- and sex-adjusted and multivariable-adjusted interval-censored Cox proportional hazard models were used to report the hazard ratios (HRs) for associations of baseline and incident vision status with driving cessation. RESULTS: The 15-year cumulative incidence of driving cessation amongst the 2379 participants was 20.7 %, with women more likely to cease driving than men (p = 0.0005). Cataract (HR 1.98 (95 % confidence interval(Cl) 1.45-2.71)) and age-related macular degeneration (HR 1.85 (95%Cl 1.37-2.50)) were associated with increased risk of driving cessation whilst presenting and best-corrected visual acuity in the better eye were protective against cessation (presenting: HR 0.96 (95%Cl 0.95-0.98); best-corrected: HR 0.93 (95%Cl 0.91-0.95)) in age- and sex-adjusted models, with these factors remaining independently associated in the multivariable-adjusted models. CONCLUSION: Cumulative incidence of driving cessation increased with older age and was higher in females. Cataract and age-related macular degeneration were independently associated with cessation, whilst better visual acuity at baseline helped prolong driving.
Subject(s)
Cataract , Macular Degeneration , Male , Humans , Female , Incidence , Australia , Visual Acuity , Risk FactorsABSTRACT
Cellular senescence is a state of permanent growth arrest that plays an important role in wound healing, tissue fibrosis, and tumor suppression. Despite senescent cells' (SnCs) pathological role and therapeutic interest, their phenotype in vivo remains poorly defined. Here, we developed an in vivo-derived senescence signature (SenSig) using a foreign body response-driven fibrosis model in a p16-CreERT2;Ai14 reporter mouse. We identified pericytes and "cartilage-like" fibroblasts as senescent and defined cell type-specific senescence-associated secretory phenotypes (SASPs). Transfer learning and senescence scoring identified these two SnC populations along with endothelial and epithelial SnCs in new and publicly available murine and human data single-cell RNA sequencing (scRNAseq) datasets from diverse pathologies. Signaling analysis uncovered crosstalk between SnCs and myeloid cells via an IL34-CSF1R-TGFßR signaling axis, contributing to tissue balance of vascularization and matrix production. Overall, our study provides a senescence signature and a computational approach that may be broadly applied to identify SnC transcriptional profiles and SASP factors in wound healing, aging, and other pathologies.
Subject(s)
Aging , Cellular Senescence , Humans , Mice , Animals , Cellular Senescence/genetics , Aging/genetics , Phenotype , Fibroblasts , Machine LearningABSTRACT
Background: The cardiovascular risk associated with different levels of hypertensive retinopathy, including mild, remains unclear. We performed an individual participant meta-analysis from 6 population-based cohort studies to determine the relationship of hypertensive retinopathy with incident cardiovascular outcomes. Methods: We identified cohort studies that objectively assessed hypertensive retinopathy from photographs, documented incident cardiovascular outcomes, and were population-based. Six studies contributed data from 11,013 individuals at baseline with 5-13 years follow-up. Participants were recruited if they had hypertension and did not have confounding conditions such as diabetic retinopathy. Main outcome measures were incident coronary heart disease (CHD), stroke and a composite endpoint of cardiovascular disease (CHD or stroke). Pooled estimates of incident risk ratios (IRR) were obtained after adjusting for age, gender, systolic blood pressure, serum total cholesterol, high density lipoprotein and smoking. Results: Among eligible participants with hypertension and without diabetes, there were 1018/9662 (10.5%) incident CHD events, 708/11,013 (6.4%) incident stroke events and 1317/9378 (14.0%) incident CVD events. Mild hypertensive retinopathy was associated with increased risk of CVD (IRR 1.13, 95% CI 1.00 to 1.27) and CHD (IRR 1.17, 95% CI 1.02 to 1.34) but not stroke; moderate hypertensive retinopathy was associated with increased risk of CVD (IRR 1.25 95% CI 1.02 to 1.53) but not stroke or CHD individually. Conclusions: In persons with hypertension, both mild and moderate hypertensive retinopathy were associated with higher CVD risk.
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The immune system is increasingly recognized as an important regulator of tissue repair. We developed a regenerative immunotherapy from the helminth Schistosoma mansoni soluble egg antigen (SEA) to stimulate production of interleukin (IL)-4 and other type 2-associated cytokines without negative infection-related sequelae. The regenerative SEA (rSEA) applied to a murine muscle injury induced accumulation of IL-4-expressing T helper cells, eosinophils, and regulatory T cells and decreased expression of IL-17A in gamma delta (γδ) T cells, resulting in improved repair and decreased fibrosis. Encapsulation and controlled release of rSEA in a hydrogel further enhanced type 2 immunity and larger volumes of tissue repair. The broad regenerative capacity of rSEA was validated in articular joint and corneal injury models. These results introduce a regenerative immunotherapy approach using natural helminth derivatives.
Subject(s)
Schistosomiasis mansoni , Animals , Mice , Schistosomiasis mansoni/therapy , Cytokines/metabolism , Schistosoma mansoni , T-Lymphocytes, Helper-Inducer , Antigens, Helminth , ImmunotherapyABSTRACT
Cell therapy has significant therapeutic potential but is often limited by poor donor cell retention and viability at the host implantation site. Biomaterials can improve cell retention by providing cells with increased cell-cell and cell-matrix contacts and materials that allow three-dimensional cell culture to better recapitulate native cell morphology and function. In this study, we engineered a scaffold that allows for cell encapsulation and sustained three-dimensional cell culture. Since cell therapy is largely driven by paracrine secretions, the material was fabricated by electrospinning to have a large internal surface area, micrometer-thin walls, and nanoscale surface pores to allow for nutrient exchange without early cell permeation. The material is degradable, which allows for less invasive removal of the implant. Here, a biodegradable poly(lactic-co-glycolic acid) (PLGA) microtube array membrane was fabricated. In vitro testing showed that the material supported the culture of human dermal fibroblasts for at least 21 days, with paracrine secretion of pro-angiogenic FGF2. In vivo xenotransplantation of human cells in an immunocompetent mouse showed that donor cells could be maintained for more than one month and the material showed no obvious toxicity. Analysis of gene expression and tissue histology surrounding the implant showed that the material produced muted inflammatory and immune responses compared to a permanent implant and increased markers of angiogenesis.
Subject(s)
Lactic Acid , Polyglycolic Acid , Mice , Humans , Animals , Polylactic Acid-Polyglycolic Acid Copolymer , Porosity , Cell SurvivalABSTRACT
Aims: Computer-aided detection systems for retinal fluid could be beneficial for disease monitoring and management by chronic age-related macular degeneration (AMD) and diabetic retinopathy (DR) patients, to assist in disease prevention via early detection before the disease progresses to a "wet AMD" pathology or diabetic macular edema (DME), requiring treatment. We propose a proof-of-concept AI-based app to help predict fluid via a "fluid score", prevent fluid progression, and provide personalized, serial monitoring, in the context of predictive, preventive, and personalized medicine (PPPM) for patients at risk of retinal fluid complications. Methods: The app comprises a convolutional neural network-Vision Transformer (CNN-ViT)-based segmentation deep learning (DL) network, trained on a small dataset of 100 training images (augmented to 992 images) from the Singapore Epidemiology of Eye Diseases (SEED) study, together with a CNN-based classification network trained on 8497 images, that can detect fluid vs. non-fluid optical coherence tomography (OCT) scans. Both networks are validated on external datasets. Results: Internal testing for our segmentation network produced an IoU score of 83.0% (95% CI = 76.7-89.3%) and a DICE score of 90.4% (86.3-94.4%); for external testing, we obtained an IoU score of 66.7% (63.5-70.0%) and a DICE score of 78.7% (76.0-81.4%). Internal testing of our classification network produced an area under the receiver operating characteristics curve (AUC) of 99.18%, and a Youden index threshold of 0.3806; for external testing, we obtained an AUC of 94.55%, and an accuracy of 94.98% and an F1 score of 85.73% with Youden index. Conclusion: We have developed an AI-based app with an alternative transformer-based segmentation algorithm that could potentially be applied in the clinic with a PPPM approach for serial monitoring, and could allow for the generation of retrospective data to research into the varied use of treatments for AMD and DR. The modular system of our app can be scaled to add more iterative features based on user feedback for more efficient monitoring. Further study and scaling up of the algorithm dataset could potentially boost its usability in a real-world clinical setting. Supplementary information: The online version contains supplementary material available at 10.1007/s13167-022-00301-5.
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Ischemic diseases including myocardial infarction (MI) and limb ischemia are some of the greatest causes of morbidity and mortality worldwide. Cell therapy is a potential treatment but is usually limited by poor survival and retention of donor cells injected at the target site. Since much of the therapeutic effects occur via cell-secreted paracrine factors, including extracellular vesicles (EVs), we developed a porous material for cell encapsulation which would improve donor cell retention and survival, while allowing EV secretion. Human donor cardiac mesenchymal cells were used as a model therapeutic cell and the encapsulation system could sustain three-dimensional cell growth and secretion of therapeutic factors. Secretion of EVs and protective growth factors were increased by encapsulation, and secreted EVs had hypoxia-protective, pro-angiogenic activities in in vitro assays. In a mouse model of limb ischemia the implant improved angiogenesis and blood flow, and in an MI model the system preserved ejection fraction %. In both instances, the encapsulation system greatly extended donor cell retention and survival compared to directly injected cells. This system represents a promising therapy for ischemic diseases and could be adapted for treatment of other diseases in the future.
Subject(s)
Exosomes , Extracellular Vesicles , Mesenchymal Stem Cells , Myocardial Infarction , Animals , Mice , Humans , Exosomes/metabolism , Cell Encapsulation , Porosity , Mesenchymal Stem Cells/metabolism , Extracellular Vesicles/metabolism , Ischemia/therapy , Myocardial Infarction/therapy , Myocardial Infarction/metabolism , Disease Models, AnimalABSTRACT
Per- and polyfluoroalkyl substances (PFAS) comprise a diverse class of chemicals used in industrial processes, consumer products, and fire-fighting foams which have become environmental pollutants of concern due to their persistence, ubiquity, and associations with adverse human health outcomes, including in pregnant persons and their offspring. Multiple PFAS are associated with adverse liver outcomes in adult humans and toxicological models, but effects on the developing liver are not fully described. Here we performed transcriptomic analyses in the mouse to investigate the molecular mechanisms of hepatic toxicity in the dam and its fetus after exposure to two different PFAS, perfluorooctanoic acid (PFOA) and its replacement, hexafluoropropylene oxide-dimer acid (HFPO-DA, known as GenX). Pregnant CD-1 mice were exposed via oral gavage from embryonic day (E) 1.5-17.5 to PFOA (0, 1, or 5 mg/kg-d) or GenX (0, 2, or 10 mg/kg-d). Maternal and fetal liver RNA was isolated (N = 5 per dose/group) and the transcriptome analyzed by Affymetrix Array. Differentially expressed genes (DEG) and differentially enriched pathways (DEP) were obtained. DEG patterns were similar in maternal liver for 5 mg/kg PFOA, 2 mg/kg GenX, and 10 mg/kg GenX (R2: 0.46-0.66). DEG patterns were similar across all 4 dose groups in fetal liver (R2: 0.59-0.81). There were more DEGs in fetal liver compared to maternal liver at the low doses for both PFOA (fetal = 69, maternal = 8) and GenX (fetal = 154, maternal = 93). Upregulated DEPs identified across all groups included Fatty Acid Metabolism, Peroxisome, Oxidative Phosphorylation, Adipogenesis, and Bile Acid Metabolism. Transcriptome-phenotype correlation analyses demonstrated > 1000 maternal liver DEGs were significantly correlated with maternal relative liver weight (R2 >0.92). These findings show shared biological pathways of liver toxicity for PFOA and GenX in maternal and fetal livers in CD-1 mice. The limited overlap in specific DEGs between the dam and fetus suggests the developing liver responds differently than the adult liver to these chemical stressors. This work helps define mechanisms of hepatic toxicity of two structurally unique PFAS and may help predict latent consequences of developmental exposure.
Subject(s)
Fluorocarbons , Adult , Humans , Female , Pregnancy , Mice , Animals , Fluorocarbons/toxicity , Oxides , Caprylates/toxicity , Fetus , PolymersABSTRACT
Dynamic post-translational modifications allow the rapid, specific, and tunable regulation of protein functions in eukaryotic cells. S-acylation is the only reversible lipid modification of proteins, in which a fatty acid, usually palmitate, is covalently attached to a cysteine residue of a protein by a zDHHC palmitoyl acyltransferase enzyme. Depalmitoylation is required for acylation homeostasis and is catalyzed by an enzyme from the alpha/beta hydrolase family of proteins usually acyl-protein thioesterase (APT1). The enzyme responsible for depalmitoylation in Trypanosoma brucei parasites is currently unknown. We demonstrate depalmitoylation activity in live bloodstream and procyclic form trypanosomes sensitive to dose-dependent inhibition with the depalmitoylation inhibitor, palmostatin B. We identified a homologue of human APT1 in Trypanosoma brucei which we named TbAPT-like (TbAPT-L). Epitope-tagging of TbAPT-L at N- and C- termini indicated a cytoplasmic localization. Knockdown or over-expression of TbAPT-L in bloodstream forms led to robust changes in TbAPT-L mRNA and protein expression but had no effect on parasite growth in vitro, or cellular depalmitoylation activity. Esterase activity in cell lysates was also unchanged when TbAPT-L was modulated. Unexpectedly, recombinant TbAPT-L possesses esterase activity with specificity for short- and medium-chain fatty acid substrates, leading to the conclusion, TbAPT-L is a lipase, not a depalmitoylase.