Tissue engineers and stem cell biologists have made exciting progress toward creating simplified models of human heart muscles or aligned monolayers to help bridge a longstanding gap between experimental animals and clinical trials. However, no existing human in vitro systems provide the direct measures of cardiac performance as a pump. Here, we developed a next-generation in vitro biomimetic model of pumping human heart chamber, and demonstrated its capability for pharmaceutical testing. From human pluripotent stem cell (hPSC)-derived ventricular cardiomyocytes (hvCM) embedded in collagen-based extracellular matrix hydrogel, we engineered a three-dimensional (3D) electro-mechanically coupled, fluid-ejecting miniature human ventricle-like cardiac organoid chamber (hvCOC). Structural characterization showed organized sarcomeres with myofibrillar microstructures. Transcript and RNA-seq analyses revealed upregulation of key Ca-handling, ion channel, and cardiac-specific proteins in hvCOC compared to lower-order 2D and 3D cultures of the same constituent cells. Clinically-important, physiologically complex contractile parameters such as ejection fraction, developed pressure, and stroke work, as well as electrophysiological properties including action potential and conduction velocity were measured: hvCOC displayed key molecular and physiological characteristics of the native ventricle, and showed expected mechanical and electrophysiological responses to a range of pharmacological interventions (including positive and negative inotropes). We conclude that such "human-heart-in-a-jar" technology could facilitate the drug discovery process by providing human-specific preclinical data during early stage drug development.
Objective This collaboration between the American College of Rheumatology and the American Association of Hip and Knee Surgeons developed an evidence‐based guideline for the perioperative management of antirheumatic drug therapy for adults with rheumatoid arthritis (RA), spondyloarthritis (SpA) including ankylosing spondylitis and psoriatic arthritis, juvenile idiopathic arthritis (JIA), or systemic lupus erythematosus (SLE) undergoing elective total hip (THA) or total knee arthroplasty (TKA). Methods A panel of rheumatologists, orthopedic surgeons specializing in hip and knee arthroplasty, and methodologists was convened to construct the key clinical questions to be answered in the guideline. A multi‐step systematic literature review was then conducted, from which evidence was synthesized for continuing versus withholding antirheumatic drug therapy and for optimal glucocorticoid management in the perioperative period. A Patient Panel was convened to determine patient values and preferences, and the Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of evidence and the strength of recommendations, using a group consensus process through a convened Voting Panel of rheumatologists and orthopedic surgeons. The strength of the recommendation reflects the degree of certainty that benefits outweigh harms of the intervention, or vice versa, considering the quality of available evidence and the variability in patient values and preferences. Results The guideline addresses the perioperative use of antirheumatic drug therapy including traditional disease‐modifying antirheumatic drugs, biologic agents, tofacitinib, and glucocorticoids in adults with RA, SpA, JIA, or SLE who are undergoing elective THA or TKA. It provides recommendations regarding when to continue, when to withhold, and when to restart these medications, and the optimal perioperative dosing of glucocorticoids. The guideline includes 7 recommendations, all of which are conditional and based on low‐ or moderate‐quality evidence. Conclusion This guideline should help decision‐making by clinicians and patients regarding perioperative antirheumatic medication management at the time of elective THA or TKA. These conditional recommendations reflect the paucity of high‐quality direct randomized controlled trial data.
Rationale Myocardial delivery of human mesenchymal stem cells (hMSCs) is an emerging therapy for treating the failing heart. However, the relative effects of hMSC-mediated heterocellular coupling (HC) and paracrine signaling (PS) on human cardiac contractility and arrhythmogenicity remain unresolved. Objective To better understand hMSC PS and HC effects on human cardiac contractility and arrhythmogenicity by integrating experimental and computational approaches. Methods and Results Extending our previous hMSC-cardiomyocyte HC computational model, we incorporated experimentally calibrated hMSC PS effects on cardiomyocyte L-type calcium channel/SERCA activity and cardiac tissue fibrosis. Excitation-contraction simulations of hMSC PS-only and combined HC+PS effects on human cardiomyocytes were representative of human engineered cardiac tissue (hECT) contractile function measurements under matched experimental treatments. Model simulations and hECTs both demonstrated hMSC-mediated effects were most pronounced under PS-only conditions, where developed force increased approximately 4-fold compared to non-hMSC-supplemented controls during physiologic 1-Hz pacing. Simulations predicted contractility of isolated healthy and ischemic adult human cardiomyocytes would be minimally sensitive to hMSC HC, driven primarily by PS. Dominance of hMSC PS was also revealed in simulations of fibrotic cardiac tissue, where hMSC PS protected from potential pro-arrhythmic effects of HC at various levels of engraftment. Finally, to study the nature of the hMSC paracrine effects on contractility, proteomic analysis of hECT/hMSC conditioned media predicted activation of PI3K/Akt signaling, a recognized target of both soluble and exosomal fractions of the hMSC secretome. Treating hECTs with exosomes-enriched, but not exosomes-depleted, fractions of the hMSC secretome recapitulated the effects observed with hMSC conditioned media on hECT developed force and expression of calcium handling genes (e.g., SERCA2a, L-type calcium channel). Conclusions Collectively, this integrated experimental and computational study helps unravel relative hMSC PS and HC effects on human cardiac contractility and arrhythmogenicity, and provides novel insight into the role of exosomes in hMSC paracrine-mediated effects on contractility.
Guidelines and recommendations developed and/or endorsed by the American College of Rheumatology (ACR) are intended to provide guidance for particular patterns of practice and not to dictate the care of a particular patient. The ACR considers adherence to the recommendations within this guideline to be voluntary, with the ultimate determination regarding their application to be made by the physician in light of each patient's individual circumstances. Guidelines and recommendations are intended to promote beneficial or desirable outcomes but cannot guarantee any specific outcome. Guidelines and recommendations developed and endorsed by the ACR are subject to periodic revision as warranted by the evolution of medical knowledge, technology, and practice. ACR recommendations are not intended to dictate payment or insurance decisions. These recommendations cannot adequately convey all uncertainties and nuances of patient care.The American College of Rheumatology is an independent, professional, medical and scientific society that does not guarantee, warrant, or endorse any commercial product or service. 1111Objective. This collaboration between the American College of Rheumatology and the American Association of Hip and Knee Surgeons developed an evidence-based guideline for the perioperative management of antirheumatic drug therapy for adults with rheumatoid arthritis (RA), spondyloarthritis (SpA) including ankylosing spondylitis and psoriatic arthritis, juvenile idiopathic arthritis (JIA), or systemic lupus erythematosus (SLE) undergoing elective total hip (THA) or total knee arthroplasty (TKA). Methods. A panel of rheumatologists, orthopedic surgeons specializing in hip and knee arthroplasty, and methodologists was convened to construct the key clinical questions to be answered in the guideline. A multi-step systematic literature review was then conducted, from which evidence was synthesized for continuing versus withholding antirheumatic drug therapy and for optimal glucocorticoid management in the perioperative period. A Patient Panel was convened to determine patient values and preferences, and the Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of evidence and the strength of recommendations, using a group consensus process through a convened Voting Panel of rheumatologists and orthopedic surgeons. The strength of the recommendation reflects the degree of certainty that benefits outweigh harms of the intervention, or vice versa, considering the quality of available evidence and the variability in patient values and preferences. Results. The guideline addresses the perioperative use of antirheumatic drug therapy including traditional diseasemodifying antirheumatic drugs, biologic agents, tofacitinib, and glucocorticoids in adults with RA, SpA, JIA, or SLE who are undergoing elective THA or TKA. It provides recommendations regarding when to continue, when to withhold, and when to restart these medications, and the optimal perioperative dosing of glucoc...
Hypertrophic cardiomyopathy (HCM) is a leading cause of sudden cardiac death that often goes undetected in the general population. HCM is also prevalent in patients with cardio-facio-cutaneous syndrome (CFCS), which is a genetic disorder characterized by aberrant signaling in the RAS/MAPK signaling cascade. Understanding the mechanisms of HCM development in such RASopathies may lead to novel therapeutic strategies, but relevant experimental models of the human condition are lacking. Therefore, the objective of this study was to develop the first 3D human engineered cardiac tissue (hECT) model of HCM. The hECTs were created using human cardiomyocytes obtained by directed differentiation of induced pluripotent stem cells derived from a patient with CFCS due to an activating BRAF mutation. The mutant myocytes were directly conjugated at a 3:1 ratio with a stromal cell population to create a tissue of defined composition. Compared to healthy patient control hECTs, BRAF-hECTs displayed a hypertrophic phenotype by culture day 6, with significantly increased tissue size, twitch force, and atrial natriuretic peptide (ANP) gene expression. Twitch characteristics reflected increased contraction and relaxation rates and shorter twitch duration in BRAF-hECTs, which also had a significantly higher maximum capture rate and lower excitation threshold during electrical pacing, consistent with a more arrhythmogenic substrate. By culture day 11, twitch force was no longer different between BRAF and wild-type hECTs, revealing a temporal aspect of disease modeling with tissue engineering. Principal component analysis identified diastolic force as a key factor that changed from day 6 to day 11, supported by a higher passive stiffness in day 11 BRAF-hECTs. In summary, human engineered cardiac tissues created from BRAF mutant cells recapitulated, for the first time, key aspects of the HCM phenotype, offering a new in vitro model for studying intrinsic mechanisms and screening new therapeutic approaches for this lethal form of heart disease.
Objective To develop updated guidelines for the perioperative management of disease‐modifying medications for patients with rheumatic diseases, specifically those with inflammatory arthritis (IA) and those with systemic lupus erythematosus (SLE), undergoing elective total hip arthroplasty (THA) or elective total knee arthroplasty (TKA). Methods We convened a panel of rheumatologists, orthopedic surgeons, and infectious disease specialists, updated the systematic literature review, and included currently available medications for the clinically relevant population, intervention, comparator, and outcomes (PICO) questions. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to rate the quality of evidence and the strength of recommendations using a group consensus process. Results This guideline updates the 2017 recommendations for perioperative use of disease‐modifying antirheumatic therapy, including traditional disease‐modifying antirheumatic drugs, biologic agents, targeted synthetic small‐molecule drugs, and glucocorticoids used for adults with rheumatic diseases, specifically for the treatment of patients with IA, including rheumatoid arthritis and spondyloarthritis, those with juvenile idiopathic arthritis, or those with SLE who are undergoing elective THA or TKA. It updates recommendations regarding when to continue, when to withhold, and when to restart these medications and the optimal perioperative dosing of glucocorticoids. Conclusion This updated guideline includes recently introduced immunosuppressive medications to help decision‐making by clinicians and patients regarding perioperative disease‐modifying medication management for patients with IA and SLE at the time of elective THA or TKA.
Objective RA patients report more adverse events (AEs) after Total Knee Arthroplasty (TKA) than patients with osteoarthritis (OA). This study evaluates 6-month post-operative AEs in a high volume center in a contemporary RA cohort compared to OA. Methods Patients with RA in an institutional registry (2007–2010) were matched 2:1 to OA by age, gender, and procedure. AEs were identified by self-report and chart review. RA specific surgical volume was determined. Baseline characteristics and adverse events were compared. Results There were 159 RA TKA and 318 OA20% of RA were on corticosteroids, 41.5% on biologics, and 67% on non-biologic DMARDs. There was no difference in comorbidities. RA specific surgical volume was high; 64% of cases were performed by surgeons with ≥ 20 RA cases during the study period. RA had worse baseline pain and function and health status (EQ-5D 0.59 vs. 0.65; p < 0.01). There were no deep infections in either group and no difference in superficial infection (9.4% RA vs. 10.1%; p = 0.82), myocardial infarction (0.7% RA vs. 0%; p = 0.33), or thromboembolism (1.3% RA vs. 0.6%; p = 0.60). Return to the operating room was more common in OA due to manipulations. OA were more likely to have adverse events at 6 months (OR 3.34, 95% CI 1.24– 9.01; p = 0.02). Conclusion In a high volume center, with high RA specific experience, RA does not increase post-operative adverse events, despite worse pre-operative function and high steroid and DMARD use, Further study to determine generalizability is needed.
Objective The patterns and risks of perioperative use of anti-tumor necrosis factor (anti-TNF)medication in patients with rheumatoid arthritis (RA) are not well studied. We examined the patterns of perioperative anti-TNF use and risk of postoperative adverse events (AE) in patients undergoing total knee replacement (TKR). Method Retrospective cohort study with followup. RA cases within a TKR registry were identified by ICD-9 code (714.0) or self-report. Mailed questionnaires queried anti-TNF use and duration of RA. AE were determined by chart review and patient self-report, and included surgical site infection, pulmonary embolus, deep venous thrombosis, pneumonia, and any infection o rre-operation within 6 months. Results There were 268 TKR cases with RA. The stop time for anti-TNF preoperatively correlated with dosing schedule; restart time was after wound healing. There were 7 surgical site infections (3%), one (0.4%) of which was a deep joint infection in bilateral TKA requiring explant. The anti-TNF group had 3.26% (3/92) local site infection versus 2.10% (3/143) in the group without anti-TNF and this difference was not statistically significant (Fisher exact test, p = 0.68). The one deep joint infection was in the anti-TNF group. Six-month AE rate was 7.61% in the anti-TNF group versus 6.99% in the group without anti-TNF (Fisher exact test, p = 1.0). Conclusion There was a low risk of infection and perioperative adverse events in patients with RA receiving anti-TNF therapy who were undergoing TKR. This raises the question whether it is necessary to stop anti-TNF for a long period prior to surgery. Given the possible risks associated with stopping anti-TNF, including worsening of disease, further study is needed to determine optimal perioperative use of anti-TNF among patients with RA undergoing TKR.
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