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1.
Immunity ; 57(6): 1324-1344.e8, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38776918

ABSTRACT

Peripheral CD8+ T cell tolerance is a checkpoint in both autoimmune disease and anti-cancer immunity. Despite its importance, the relationship between tolerance-induced states and other CD8+ T cell differentiation states remains unclear. Using flow cytometric phenotyping, single-cell RNA sequencing (scRNA-seq), and chromatin accessibility profiling, we demonstrated that in vivo peripheral tolerance to a self-antigen triggered a fundamentally distinct differentiation state separate from exhaustion, memory, and functional effector cells but analogous to cells defectively primed against tumors. Tolerant cells diverged early and progressively from effector cells, adopting a transcriptionally and epigenetically distinct state within 60 h of antigen encounter. Breaching tolerance required the synergistic actions of strong T cell receptor (TCR) signaling and inflammation, which cooperatively induced gene modules that enhanced protein translation. Weak TCR signaling during bystander infection failed to breach tolerance due to the uncoupling of effector gene expression from protein translation. Thus, tolerance engages a distinct differentiation trajectory enforced by protein translation defects.


Subject(s)
CD8-Positive T-Lymphocytes , Cell Differentiation , Immune Tolerance , Protein Biosynthesis , Receptors, Antigen, T-Cell , CD8-Positive T-Lymphocytes/immunology , Animals , Cell Differentiation/immunology , Mice , Receptors, Antigen, T-Cell/metabolism , Receptors, Antigen, T-Cell/immunology , Immune Tolerance/immunology , Protein Biosynthesis/immunology , Signal Transduction/immunology , Mice, Inbred C57BL , Autoantigens/immunology
2.
BMC Genomics ; 25(1): 251, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38448820

ABSTRACT

BACKGROUND: The Illumina family of Infinium Methylation BeadChip microarrays has been widely used over the last 15 years for genome-wide DNA methylation profiling, including large-scale and population-based studies, due to their ease of use and cost effectiveness. Succeeding the popular HumanMethylationEPIC BeadChip (EPICv1), the recently released Infinium MethylationEPIC v2.0 BeadChip (EPICv2) claims to extend genomic coverage to more than 935,000 CpG sites. Here, we comprehensively characterise the reproducibility, reliability and annotation of the EPICv2 array, based on bioinformatic analysis of both manifest data and new EPICv2 data from diverse biological samples. RESULTS: We find a high degree of reproducibility with EPICv1, evidenced by comparable sensitivity and precision from empirical cross-platform comparison incorporating whole genome bisulphite sequencing (WGBS), and high correlation between technical sample replicates, including between samples with DNA input levels below the manufacturer's recommendation. We provide a full assessment of probe content, evaluating genomic distribution and changes from previous array versions. We characterise EPICv2's new feature of replicated probes and provide recommendations as to the superior probes. In silico analysis of probe sequences demonstrates that probe cross-hybridisation remains a significant problem in EPICv2. By mapping the off-target sites at single nucleotide resolution and comparing with WGBS we show empirical evidence for preferential off-target binding. CONCLUSIONS: Overall, we find EPICv2 a worthy successor to the previous Infinium methylation microarrays, however some technical issues remain. To support optimal EPICv2 data analysis we provide an expanded version of the EPICv2 manifest to aid researchers in understanding probe design, data processing, choosing appropriate probes for analysis and for integration with methylation datasets from previous versions of the Infinium Methylation BeadChip.


Subject(s)
Computational Biology , DNA Methylation , Sulfites , Reproducibility of Results , Data Analysis
3.
J Autoimmun ; 142: 103129, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37952292

ABSTRACT

BACKGROUND: PR3 autoantibodies are essential to the diagnosis and monitoring of granulomatosus with polyangiitis, but to date no PR3 autoantibody sequences have been published. OBJECTIVES: To identify and characterise PR3-specific B cells from the peripheral blood of patients with PR3 autoantibodies. METHODS: Peripheral blood mononuclear cells from seven patients with PR3 autoantibodies were stained with PR3. B cells that bound PR3 underwent single cell sorting, transcriptome sequencing, and their immunoglobulin sequences expressed as antibodies and tested for PR3-specificity by ELISA. RESULTS: We identified 19 PR3-specific B cells from only one PR3-seropositive patient at a low frequency (0.0075 % of B cells) in the peripheral blood. These were polyclonal, IgG+ and enriched for IgG4, lambda pairing, IGHJ6 gene usage, CDRH3 length, IGHE and CD71 expression. They demonstrated relatively low levels of somatic hypermutation and variably reduced PR3 binding when reverted to germline. CONCLUSIONS: Identifying PR3-specific B cells in the peripheral blood is possible but challenging and those we did identify exhibited features suggesting that PR3-self reactivity may occur early in B-cell development.


Subject(s)
Granulomatosis with Polyangiitis , Humans , Myeloblastin , Antibodies, Antineutrophil Cytoplasmic , Leukocytes, Mononuclear/metabolism , Autoantibodies
4.
South Med J ; 116(11): 899-905, 2023 11.
Article in English | MEDLINE | ID: mdl-37913810

ABSTRACT

OBJECTIVE: To evaluate the impact of implementing a comprehensive secondary onboarding and development program within a hospital medicine group at a large tertiary academic medical institution. METHODS: This was a mixed-methods study with physician and advanced practice providers (APPs) at an academic medical institution. RESULTS: For quantitative methods, improvement in competencies was determined using a pre-and posttest for APPs and pre- and postevaluation scores from collaborating physicians. APPs also participated in a pre- and post-self-assessment. For qualitative methods, experiences in the secondary onbo.arding and development program were assessed using semistructured interviews. CONCLUSIONS: For quantitative results, there were a total of 25 APPs who completed the pre- and posttest and were evaluated by at least 9 physicians. The average pretest score for APPs was 71.7% and the average posttest score was 83.0%. The average score for physicians' evaluations of APPs was 4.24/5 and increased to 4.38/5 in the postprogram evaluations. The average score for APP self-assessment pretraining was 3.52/5 and after the 12-month onboarding training, average scores increased to 3.84/5. For qualitative results, 4 APPs and 6 physicians were interviewed. Three of the APPs reported having more confidence in treating patients, whereas 1 APP viewed the program as a refresher course. All of the APPs mentioned that they would recommend the program to other APPs. Physicians reported that the program was beneficial in standardizing the care provided among the different types of APPs (physician assistants and nurse practitioners). All of the physicians also would recommend the program to other physicians and APPs.


Subject(s)
Nurse Practitioners , Physician Assistants , Physicians , Humans , Nurse Practitioners/education
5.
Nat Commun ; 13(1): 7543, 2022 12 07.
Article in English | MEDLINE | ID: mdl-36477661

ABSTRACT

T cell exhaustion is a hallmark of hepatitis C virus (HCV) infection and limits protective immunity in chronic viral infections and cancer. Limited knowledge exists of the initial viral and immune dynamics that characterise exhaustion in humans. We studied longitudinal blood samples from a unique cohort of individuals with primary infection using single-cell multi-omics to identify the functions and phenotypes of HCV-specific CD8+ T cells. Early elevated IFN-γ response against the transmitted virus is associated with the rate of immune escape, larger clonal expansion, and early onset of exhaustion. Irrespective of disease outcome, we find heterogeneous subsets of progenitors of exhaustion, based on the level of PD-1 expression and loss of AP-1 transcription factors. Intra-clonal analysis shows distinct trajectories with multiple fates and evolutionary plasticity of precursor cells. These findings challenge the current paradigm on the contribution of CD8+ T cells to HCV disease outcome and provide data for future studies on T cell differentiation in human infections.


Subject(s)
CD8-Positive T-Lymphocytes , Virus Diseases , Humans
6.
Immunity ; 55(12): 2386-2404.e8, 2022 12 13.
Article in English | MEDLINE | ID: mdl-36446385

ABSTRACT

The association between cancer and autoimmune disease is unexplained, exemplified by T cell large granular lymphocytic leukemia (T-LGL) where gain-of-function (GOF) somatic STAT3 mutations correlate with co-existing autoimmunity. To investigate whether these mutations are the cause or consequence of CD8+ T cell clonal expansions and autoimmunity, we analyzed patients and mice with germline STAT3 GOF mutations. STAT3 GOF mutations drove the accumulation of effector CD8+ T cell clones highly expressing NKG2D, the receptor for stress-induced MHC-class-I-related molecules. This subset also expressed genes for granzymes, perforin, interferon-γ, and Ccl5/Rantes and required NKG2D and the IL-15/IL-2 receptor IL2RB for maximal accumulation. Leukocyte-restricted STAT3 GOF was sufficient and CD8+ T cells were essential for lethal pathology in mice. These results demonstrate that STAT3 GOF mutations cause effector CD8+ T cell oligoclonal accumulation and that these rogue cells contribute to autoimmune pathology, supporting the hypothesis that somatic mutations in leukemia/lymphoma driver genes contribute to autoimmune disease.


Subject(s)
Autoimmune Diseases , Leukemia, Large Granular Lymphocytic , Animals , Mice , Autoimmune Diseases/genetics , Autoimmune Diseases/pathology , CD8-Positive T-Lymphocytes , Gain of Function Mutation , Leukemia, Large Granular Lymphocytic/genetics , Leukemia, Large Granular Lymphocytic/pathology , Mutation , NK Cell Lectin-Like Receptor Subfamily K/genetics , STAT3 Transcription Factor/genetics , STAT3 Transcription Factor/metabolism
7.
Clin Transl Med ; 12(10): e1030, 2022 10.
Article in English | MEDLINE | ID: mdl-36178085

ABSTRACT

BACKGROUND: Prostate cancer is a clinically heterogeneous disease with a subset of patients rapidly progressing to lethal-metastatic prostate cancer. Current clinicopathological measures are imperfect predictors of disease progression. Epigenetic changes are amongst the earliest molecular changes in tumourigenesis. To find new prognostic biomarkers to enable earlier intervention and improved outcomes, we performed methylome sequencing of DNA from patients with localised prostate cancer and long-term clinical follow-up. METHODS: We used whole-genome bisulphite sequencing (WGBS) to comprehensively map and compare DNA methylation of radical prostatectomy tissue between patients with lethal disease (n = 7) and non-lethal (n = 8) disease (median follow-up 19.5 years). Validation of differentially methylated regions (DMRs) was performed in an independent cohort (n = 185, median follow-up 15 years) using targeted multiplex bisulphite sequencing of candidate regions. Survival was assessed via univariable and multivariable analyses including clinicopathological measures (log-rank and Cox regression models). RESULTS: WGBS data analysis identified cancer-specific methylation patterns including CpG island hypermethylation, and hypomethylation of repetitive elements, with increasing disease risk. We identified 1420 DMRs associated with prostate cancer-specific mortality (PCSM), which showed enrichment for gene sets downregulated in prostate cancer and de novo methylated in cancer. Through comparison with public prostate cancer datasets, we refined the DMRs to develop an 18-gene prognostic panel. Applying this panel to an independent cohort, we found significant associations between PCSM and hypermethylation at EPHB3, PARP6, TBX1, MARCH6 and a regulatory element within CACNA2D4. Strikingly in a multivariable model, inclusion of CACNA2D4 methylation was a better predictor of PCSM versus grade alone (Harrell's C-index: 0.779 vs. 0.684). CONCLUSIONS: Our study provides detailed methylome maps of non-lethal and lethal prostate cancer and identifies novel genic regions that distinguish these patient groups. Inclusion of our DNA methylation biomarkers with existing clinicopathological measures improves prognostic models of prostate cancer mortality, and holds promise for clinical application.


Subject(s)
Epigenome , Prostatic Neoplasms , ADP Ribose Transferases/genetics , DNA , Epigenesis, Genetic/genetics , Humans , Male , Prognosis , Prostatic Neoplasms/diagnosis , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Sulfites
8.
MedEdPORTAL ; 18: 11242, 2022.
Article in English | MEDLINE | ID: mdl-35539004

ABSTRACT

Introduction: Pharmacology is an important learning topic in preclinical medical education. Simulated patient encounters allow students to apply basic science knowledge in a clinical setting and have been useful in previous studies of pharmacology education. We developed a standardized patient (SP) encounter to reinforce antiviral pharmacology content for first-year medical students. Methods: Students were instructed to recommend a medication for shingles during an SP encounter and to answer questions from the SP on mechanism of action and adverse effects. Students then attended a large-group debrief session. Following the activity, students evaluated the exercise through a voluntary survey. For knowledge assessment, students were randomized into two groups to complete three multiple-choice questions either before or after the learning activity. Results: In 2020 and 2021, 144 and 145 students, respectively, participated. In 2020, there was no significant difference in the proportion of correct answers between the pre- and postsimulation groups (p > .05). In 2021, the postsimulation group significantly outperformed the presimulation group in knowledge of mechanism of action (p < .01) and adverse effects (p < .01), but no difference was seen between the groups regarding medication selection (p = .27). Most learners assessed the instructional design as effective for the tasks assigned. Discussion: This SP activity provided an opportunity for early medical students to practice integrating antiviral pharmacology knowledge into a patient encounter and was well received by learners. The instructional method offers a clinically relevant approach for reinforcing pharmacology knowledge for preclinical medical students.


Subject(s)
Students, Medical , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Humans , Learning
9.
J Allergy Clin Immunol ; 150(4): 931-946, 2022 10.
Article in English | MEDLINE | ID: mdl-35469842

ABSTRACT

BACKGROUND: Lymphocyte differentiation is regulated by coordinated actions of cytokines and signaling pathways. IL-21 activates STAT1, STAT3, and STAT5 and is fundamental for the differentiation of human B cells into memory cells and antibody-secreting cells. While STAT1 is largely nonessential and STAT3 is critical for this process, the role of STAT5 is unknown. OBJECTIVES: This study sought to delineate unique roles of STAT5 in activation and differentiation of human naive and memory B cells. METHODS: STAT activation was assessed by phospho-flow cytometry cell sorting. Differential gene expression was determined by RNA-sequencing and quantitative PCR. The requirement for STAT5B in B-cell and CD4+ T-cell differentiation was assessed using CRISPR-mediated STAT5B deletion from B-cell lines and investigating primary lymphocytes from individuals with germline STAT5B mutations. RESULTS: IL-21 activated STAT5 and strongly induced SOCS3 in human naive, but not memory, B cells. Deletion of STAT5B in B-cell lines diminished IL-21-mediated SOCS3 induction. PBMCs from STAT5B-null individuals contained expanded populations of immunoglobulin class-switched B cells, CD21loTbet+ B cells, and follicular T helper cells. IL-21 induced greater differentiation of STAT5B-deficient B cells into plasmablasts in vitro than B cells from healthy donors, correlating with higher expression levels of transcription factors promoting plasma cell formation. CONCLUSIONS: These findings reveal novel roles for STAT5B in regulating IL-21-induced human B-cell differentiation. This is achieved by inducing SOCS3 to attenuate IL-21 signaling, and BCL6 to repress class switching and plasma cell generation. Thus, STAT5B is critical for restraining IL-21-mediated B-cell differentiation. These findings provide insights into mechanisms underpinning B-cell responses during primary and subsequent antigen encounter and explain autoimmunity and dysfunctional humoral immunity in STAT5B deficiency.


Subject(s)
Cytokines , STAT5 Transcription Factor , Cell Differentiation , Cytokines/metabolism , Homeostasis , Humans , Immunoglobulin Isotypes/metabolism , RNA , STAT5 Transcription Factor/genetics , STAT5 Transcription Factor/metabolism
10.
APMIS ; 130(7): 383-396, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35394091

ABSTRACT

Cellular mechanisms and/or microbiological interactions which contribute to chronic diabetes related foot ulcers (DRFUs) were explored using serially collected tissue specimens from chronic DRFUs and control healthy foot skin. Total RNA was isolated for next-generation sequencing. We found differentially expressed genes (DEGs) and enriched hallmark gene ontology biological processes upregulated in chronic DRFUs which primarily functioned in the host immune response including: (i) Inflammatory response; (ii) TNF signalling via NFKB; (iii) IL6 JAK-STAT3 signalling; (iv) IL2 STAT5 signalling and (v) Reactive oxygen species. A temporal analysis identified RN7SL1 signal recognition protein and IGHG4 immunoglobulin protein coding genes as being the most upregulated genes after the onset of treatment. Testing relative temporal changes between healing and non-healing DRFUs identified progressive upregulation in healed wounds of CXCR5 and MS4A1 (CD20), both canonical markers of lymphocytes (follicular B cells/follicular T helper cells and B cells, respectively). Collectively, our RNA-seq data provides insights into chronic DRFU pathogenesis.


Subject(s)
Diabetes Mellitus , Diabetic Foot , Diabetic Foot/genetics , Humans , Skin , Wound Healing/genetics
11.
Med Sci Educ ; 32(2): 463-471, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35251766

ABSTRACT

Introduction: Assessment of medical students' clinical skills (CS) remains a challenge. Little is known about early predictors of future CS performance. This study examines the relationship between students' pre-clerkship clinical skills (PCCS) performance and year 3 clerkship performance measures. Methods: The authors performed a retrospective analysis of four medical student cohorts who matriculated between 2014 and 2017 and participated in a longitudinal pre-clerkship CS curriculum. A total of 440 students were included in the analyses. Students' clinical skills were assessed through a series of PCCS exams, each consisting of a single standardized patient encounter. First-year PCCS exams assessed history taking, physical examination, professionalism, and communication skills; second-year PCCS exams also assessed clinical documentation and clinical reasoning skills. Evaluators assigned a grade of "satisfactory," "borderline," or "unsatisfactory" for each skill set. Regression analyses compared year 3 performance outcomes between students with one or more "unsatisfactory" or "borderline" PCCS skill set grades and students assessed as "satisfactory" for all PCCS skill set assessments. Results: Thirty-two percent (n = 140) of the 440 students had at least one borderline or unsatisfactory (US) PCCS skill set grade. These students performed significantly worse on year 3 National Board of Medical Examiner subject exams, workplace-based clinical performance evaluations, and overall year 3 performance compared to students who passed all PCCS exam components. In addition, a higher percentage of students with PCCS performance deficiencies failed the United States Medical Licensing Examination Step 2 CS exam on the first attempt versus students who passed all PCCS exam components. Conclusions: PCCS exam performance at our institution aligned with future student performance on multiple year 3 clerkship outcome measures. This pre-clerkship performance data can be used to identify at-risk students who would benefit from additional resources to achieve competency in the clerkship environment and future medical training. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-022-01519-8.

12.
Teach Learn Med ; 34(1): 43-59, 2022.
Article in English | MEDLINE | ID: mdl-35100913

ABSTRACT

Phenomenon Medical schools are tasked with selecting applicants who will excel in a rigorous curriculum and successfully perform as future physicians. While many studies have assessed quantitative prematriculation data for predicting success in medical school, fewer studies have assessed for qualitative prematriculation factors influencing medical school performance. A recent study revealed that medical students with at least one year of varsity level college athletics participation outperformed their peers on United States Medical Licensing board exams and clinical clerkships. The current study sought to explore medical student, medical school faculty, and college coach perspectives about factors explaining why medical students with collegiate athletic experience succeed in medical school. Approach: In 2019, the authors conducted semi-structured interviews with medical students with collegiate athletic experience, medical school faculty with experience educating student athletes, and college coaches with experience training student athletes who matriculated into medical school. The interview transcripts were systematically coded and analyzed for themes using a grounded theory approach. Participants were recruited and interviewed until saturation of data was reached. Findings: Fifteen medical students with collegiate athletic experience, five medical school faculty, and three collegiate coaches participated in the study. Six themes were identified as important factors explaining the academic success of these students in medical school and each of these themes appeared in student, faculty, and coach interviews: goal setting, goal pursuit, and performance appraisal; development of time management, planning, and organizational skills; development of team values and teamwork skills; development of communication and interpersonal skills; acceptance of, coping strategies for, and resilient response to stress and adversity; and prioritization of personal wellness. Participants described meaningful connections between these attributes and skills, suggesting the students' development, transfer, and application of them is interrelated. Insights: In this study, academic success of medical students with collegiate athletic experience was attributed to specific skills and attributes developed during college. The grounded theory life skills transfer model can explain transfer of these attributes and skills from college to the medical school setting. Theoretical frameworks and empirical study findings from the sociology, educational psychology, sports psychology, and medical education literature provide helpful lenses for understanding why these skills and attributes confer success among student athletes in medical school. These findings offer important insights on skill development that may support the academic success of all medical students.


Subject(s)
Schools, Medical , Students, Medical , Athletes , Curriculum , Faculty, Medical , Humans , United States
13.
Cell Rep ; 38(3): 110259, 2022 01 18.
Article in English | MEDLINE | ID: mdl-35045301

ABSTRACT

CD21low age-associated or atypical memory B cells are autoantibody enriched and poised for plasma cell differentiation. These cells overaccumulate in chronic infections, autoimmune disease, and immunodeficiency, posing the question of what checkpoints normally oppose their accumulation. Here, we reveal a critical role for paralogous calcium-NFAT-regulated transcription factors EGR2 and EGR3 that are induced in self-reactive B cells. CD21low and B1 B cells lacking EGR2 and EGR3 accumulate and circulate in young mice in numbers 10- to 20-fold greater than normal and overexpress a large set of EGR2 ChIP-seq target genes, including known drivers of plasma cell differentiation. Most follicular B cells constitutively express Egr2 proportionally to surface IgM downregulation by self-antigens, and EGR2/3 deficiency abolishes this cardinal feature of B cell anergy. These results explain the cardinal features of B cell anergy, define a key transcriptional checkpoint repressing CD21low B cell formation, and inform how NFATC1 or EGR2 mutations promote B1 cell-derived chronic lymphocytic leukemias.


Subject(s)
B-Lymphocytes/immunology , Clonal Anergy/immunology , Early Growth Response Protein 2/immunology , Early Growth Response Protein 3/immunology , Animals , Autoimmune Diseases/immunology , Autoimmune Diseases/metabolism , Autoimmunity/immunology , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/metabolism , B-Lymphocytes/metabolism , Early Growth Response Protein 2/metabolism , Early Growth Response Protein 3/metabolism , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/immunology , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Male , Mice , Receptors, Complement 3d/immunology
14.
APMIS ; 130(12): 751-762, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34888950

ABSTRACT

Virtually all diabetes-related foot ulcers (DRFUs) will become colonized by microorganisms that may increase the risk of developing an infection. The reasons why some ulcerations develop acute clinical infections (AI-DRFUs) whilst others develop chronic infection (CI-DRFUs) and the preceding host-microbe interactions in vivo remain largely unknown. Establishing that acute and chronic infections are distinct processes requires demonstrating that these are two different strategies employed by microbes when interacting with a host. In this study, dual-RNA seq was employed to differentiate the host-microbe metatranscriptome between DRFUs that had localized chronic infection or acute clinical infection. Comparison of the host metatranscriptome in AI-DRFUs relative to CI-DRFUs identified upregulated differentially expressed genes (DEGs) that functioned as regulators of vascular lymphatic inflammatory responses, T-cell signalling and olfactory receptors. Conversely, CI-DRFUs upregulated DEGs responsible for cellular homeostasis. Gene set enrichment analysis using Hallmark annotations revealed enrichment of immune and inflammatory profiles in CI-DRFUs relative to AI-DRFUs. Analysis of the microbial metatranscriptome identified the DEGs being enriched within AI-DRFUs relative to CI-DRFUs included several toxins, two-component systems, bacterial motility, secretion systems and genes encoding for energy metabolism. Functions relevant to DRFU pathology were further explored, including biofilm and bacterial pathogenesis. This identified that the expression of biofilm-associated genes was higher within CI-DRFUs compared to that of AI-DRFUs, with mucR being the most highly expressed gene. Collectively, these data provide insights into the host-microbe function in two clinically-distinct infective phenotypes that affect DRFUs. The data reveal that bacteria in acutely infected DRFUs prioritize motility over biofilm and demonstrate greater pathogenicity and mechanisms, which likely subvert host cellular and immune pathways to establish infection. Upregulation of genes for key vascular inflammatory mediators in acutely infected ulcers may contribute, in part, to the clinical picture of a red, hot, swollen foot, which differentiates an acutely infected ulcer from that of a chronic infection.


Subject(s)
Diabetes Mellitus , Diabetic Foot , Humans , Diabetic Foot/genetics , Persistent Infection , Virulence/genetics , Bacteria/genetics , Gene Expression Profiling
15.
Med Sci Educ ; 31(2): 325-329, 2021 Apr.
Article in English | MEDLINE | ID: mdl-34457887

ABSTRACT

BACKGROUND: Integrating bioethical concepts into preclinical medical school curriculum and engaging early medical learners in bioethics are a challenge. ACTIVITY: A total of 140 medical students participated in a 2-h simulation activity consisting of a series of standardized patient (SP) encounters. RESULTS: A total of 41 of 140 students (29%) completed the learner evaluation survey. Ninety-one percent thought that the SP encounter was relevant to their role as a future physician. Ninety-three percent of students rated the exercise as highly effective. CONCLUSIONS: SP encounters enhance preclinical medical students' engagement with bioethics and provide learners practice applying these concepts to clinically relevant scenarios.

16.
Nucleic Acids Res ; 49(19): e109, 2021 11 08.
Article in English | MEDLINE | ID: mdl-34320181

ABSTRACT

Whole genome bisulphite sequencing (WGBS) permits the genome-wide study of single molecule methylation patterns. One of the key goals of mammalian cell-type identity studies, in both normal differentiation and disease, is to locate differential methylation patterns across the genome. We discuss the most desirable characteristics for DML (differentially methylated locus) and DMR (differentially methylated region) detection tools in a genome-wide context and choose a set of statistical methods that fully or partially satisfy these considerations to compare for benchmarking. Our data simulation strategy is both biologically informed-employing distribution parameters derived from large-scale consortium datasets-and thorough. We report DML detection ability with respect to coverage, group methylation difference, sample size, variability and covariate size, both marginally and jointly, and exhaustively with respect to parameter combination. We also benchmark these methods on FDR control and computational time. We use this result to backend and introduce an expanded version of DMRcate: an existing DMR detection tool for microarray data that we have extended to now call DMRs from WGBS data. We compare DMRcate to a set of alternative DMR callers using a similarly realistic simulation strategy. We find DMRcate and RADmeth are the best predictors of DMRs, and conclusively find DMRcate the fastest.


Subject(s)
DNA Methylation , DNA/metabolism , Epigenesis, Genetic , Genome, Human , Sequence Analysis, DNA/statistics & numerical data , Benchmarking , Computer Simulation , CpG Islands , DNA/genetics , Genomics/methods , Humans , Sample Size , Sulfites/chemistry , Whole Genome Sequencing
17.
Nat Commun ; 12(1): 2782, 2021 05 13.
Article in English | MEDLINE | ID: mdl-33986293

ABSTRACT

Chronic stimulation of CD8+ T cells triggers exhaustion, a distinct differentiation state with diminished effector function. Exhausted cells exist in multiple differentiation states, from stem-like progenitors that are the key mediators of the response to checkpoint blockade, through to terminally exhausted cells. Due to its clinical relevance, there is substantial interest in defining the pathways that control differentiation and maintenance of these subsets. Here, we show that chronic antigen induces the anergy-associated transcription factor EGR2 selectively within progenitor exhausted cells in both chronic LCMV and tumours. EGR2 enables terminal exhaustion and stabilizes the exhausted transcriptional state by both direct EGR2-dependent control of key exhaustion-associated genes, and indirect maintenance of the exhausted epigenetic state. We show that EGR2 is a regulator of exhaustion that epigenetically and transcriptionally maintains the differentiation competency of progenitor exhausted cells.


Subject(s)
CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/pathology , Clonal Anergy/immunology , Early Growth Response Protein 2/metabolism , Lymphopoiesis/physiology , Animals , Antigens/immunology , CD4-Positive T-Lymphocytes/immunology , Early Growth Response Protein 2/biosynthesis , Mice , Mice, Inbred C57BL , Mice, Knockout
18.
NPJ Biofilms Microbiomes ; 7(1): 29, 2021 03 22.
Article in English | MEDLINE | ID: mdl-33753735

ABSTRACT

Diabetic foot infections (DFIs) are a major cause of hospitalization and can lead to lower extremity amputation. In this pilot study, we used a multiomics approach to explore the host-microbe complex within DFIs. We observed minimal differences in the overall microbial composition between PEDIS infection severities, however Staphylococcus aureus and Streptococcus genera were abundant and highly active in most mild to moderate DFIs. Further, we identified the significant enrichment of several virulence factors associated with infection pathogenicity belonging to both Staphylococcus aureus and Streptococcus. In severe DFIs, patients demonstrated a greater microbial diversity and differential gene expression demonstrated the enrichment of multispecies virulence genes suggestive of a complex polymicrobial infection. The host response in patients with severe DFIs was also significantly different as compared to mild to moderate DFIs. This was attributed to the enrichment of host genes associated with inflammation, acute phase response, cell stress and broad immune-related responses, while those associated with wound healing and myogenesis were significantly depleted.


Subject(s)
Bacteria/classification , Coinfection/genetics , Diabetic Foot/microbiology , Gene Expression Profiling/methods , Metagenomics/methods , Virulence Factors/genetics , Bacteria/genetics , Bacteria/isolation & purification , Bacteria/pathogenicity , Coinfection/microbiology , Diabetic Foot/genetics , Female , Gene Expression Regulation, Bacterial , Host-Pathogen Interactions , Humans , Male , Muscle Development , Phylogeny , Pilot Projects , Prospective Studies , Sequence Analysis, RNA , Severity of Illness Index , Staphylococcus aureus/classification , Staphylococcus aureus/genetics , Staphylococcus aureus/isolation & purification , Staphylococcus aureus/pathogenicity , Streptococcus/classification , Streptococcus/genetics , Streptococcus/isolation & purification , Streptococcus/pathogenicity , Wound Healing
19.
MedEdPORTAL ; 16: 11016, 2020 11 12.
Article in English | MEDLINE | ID: mdl-33204840

ABSTRACT

Introduction: Understanding population health in the context of infectious disease outbreaks is an important physician competency. However, identifying effective ways to engage early medical students in this content remains a challenge. We designed an innovative pandemic simulation for first-year medical students utilizing the pop culture theme of zombies. Methods: This 2.5-hour simulation was conducted in 2018 and 2020 during students' virology course. Student teams collected and analyzed data to formulate hypotheses for the source pathogen. The teams completed reports explaining their diagnostic hypotheses, infection containment recommendations, and resource allocation recommendations. Learners completed an evaluation of the simulation through an online survey. Responses were analyzed using descriptive statistics; narrative responses were analyzed qualitatively for themes. A content analysis was performed on students' reports. Results: Two hundred eighty-four medical students participated in this activity. Nearly all respondents agreed that the small-group format (98%, 2018 and 2020) and pace and duration (92%, 2018; 94%, 2020) were appropriate and that the activity was intellectually stimulating (97%, 2018; 96%, 2020). Learner engagement measures were high (90%-97%, 2018; 83%-96%, 2020). Analysis of students' reports revealed evidence of cognitive integration of virology, population health, and bioethics concepts, including integration of new learning content. Discussion: Collaborative problem-solving during a simulated zombie-themed pandemic provided preclinical medical students with an engaging opportunity to integrate virology, population health, and bioethics concepts. Implementing this event required advanced planning, use of multiple spaces, learning materials preparation, and recruitment of several faculty, staff, and actors.


Subject(s)
Bioethics , Population Health , Students, Medical , Humans , Learning , Pandemics
20.
MedEdPORTAL ; 16: 10957, 2020 09 09.
Article in English | MEDLINE | ID: mdl-32934980

ABSTRACT

Introduction: Virology is inherently challenging due to the sheer volume of information medical students are responsible for learning. Cognitive integration of this content is critical for early medical students to practice applying this knowledge to diagnostic problem-solving. Simulation offers learners engaging opportunities to practice cognitive integration. We developed a simulated clinic activity for first-year medical students consisting of standardized patient (SP) encounters representing viral infections. Methods: Student small groups rotated through eight SP encounters during which they collected patient histories, reviewed physical exam findings, and developed a differential diagnosis and diagnostic plan for each case. The instructor debriefed students on the cases afterward. We assessed students' evaluation of the activity through online surveys. Results: Two hundred seventy-eight students participated in the simulated clinic in 2018 and 2019. Students rated the activity as very effective for learning about the infections represented and for providing opportunities to integrate clinical skills. Students agreed that the event's instructional design was appropriate for its objectives and that the problem-solving aspect was intellectually stimulating. They indicated that the most effective aspects were solidifying illness scripts for the infections represented, integrating knowledge and skills to diagnose patients in a realistic clinical context, and working collaboratively to problem-solve. Discussion: The simulated virology clinic is an effective method for providing students opportunities to integrate microbiology and clinical skills and has been positively received by students. This instructional method offers learners an opportunity to solidify illness scripts for viral infections using an interactive, collaborative approach.


Subject(s)
Education, Medical, Undergraduate , Students, Medical , Ambulatory Care Facilities , Clinical Competence , Humans , Problem Solving
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