Citations

Abstract Reprogramming of aged donor tissue cells into induced pluripotent stem cells (A-iPSC) preserved the epigenetic memory of aged-donor tissue, defined as genomic instability and poor tissue differentiation in our previous study. The unbalanced expression of RNA exosome subunits affects the RNA degradation complex function and is associated with geriatric diseases including premature aging and cancer progression. We hypothesized that the age-dependent progressive subtle dysregulation of EXOSC2 (exosome component 2) causes the aging traits (abnormal cell cycle and poor tissue differentiation). We used embryonic stem cells as a tool to study EXOSC2 function as the aging trait epigenetic memory determined in A-iPSC because these aging traits could not be studied in senesced aged cells or immortalized cancer cells. We found that the regulatory subunit of PP2A phosphatase, PPP2R5E, is a key target of EXOSC2 and this regulation is preserved in stem cells and cancer.

Background/Purpose APS ACTION Registry was created to study the natural course of antiphospholipid syndrome (APS) over 10 years in persistently antiphospholipid antibody (aPL) positive patients with or without systemic autoimmune rheumatic diseases (SARDs). Our primary objective was to compare the characteristics of aPL-positive patients with or without thrombocytopenia (TP) and/or autoimmune hemolytic anemia (AIHA). Methods The registry inclusion criteria are positive aPL based on the Revised Sapporo APS Classification Criteria, tested at least twice within 1 year prior to enrollment. For the primary comparison of demographic, clinical, and serologic characteristics in this retrospective study, we divided patients into two groups: TP/AIHA ever and never. Thrombocytopenia was defined as a platelet count of <100,000 x 10 9 /L tested twice at least 12 weeks apart, and AIHA was defined as anemia with hemolysis and a positive direct antiglobulin test (DAT). For the secondary analysis, we compared patients with TP versus AIHA, and the immunosuppressive use stratified by systemic lupus erythematosus (SLE) classification. Results As of April 2022, of 1,039 patients (primary aPL/APS: 618 [59%]; SLE classification: 334 [31%]) included in the registry, 228 (22%) had baseline (historical or current) TP and/or AIHA (TP only: 176 [17%]; AIHA only: 35 [3%], and both: 17 [2%]). Thrombocytopenia and/or AIHA was significantly associated with Asian race, SLE classification, cardiac valve disease, catastrophic/microvascular APS, triple aPL (lupus anticoagulant, anticardiolipin antibody, and anti-β 2 -glycoprotein-I antibody) positivity, and SLE-related serologic and inflammatory markers. When 101/618 (16%) primary aPL/APS patients and 101/334 (34%) SLE patients with TP and/or AIHA were compared, azathioprine and mycophenolate mofetil were more commonly reported in lupus patients, however corticosteroid, intravenous immunoglobulin, and rituximab use were similar between groups. Conclusion In our large multi-center international cohort of persistently aPL-positive patients, approximately one-fifth had active or historical TP and/or AIHA at registry entry; half of these patients had additional SLE. Cardiac valve disease, catastrophic/microvascular APS, and triple aPL-positivity were aPL-related clinical and laboratory manifestations associated with TP and/or AIHA, suggesting a more severe APS clinical phenotype in aPL-patients with TP and/or AIHA.

Background: Cognitive change is an important factor in understanding dementia. Estimating effects of exposures on cognitive change requires choosing an analytical timescale, typically time on study or current age. There is limited consensus regarding timescale choice in epidemiologic cognitive aging research. Methods: Using a coordinated analytic approach in 10 cohorts of older adults, we evaluated whether estimated effects of two exposures on memory change differed depending on timescale (time on study or current age). We modeled effects of apolipoprotein-E (APOE) ε4 genotype (a time-invariant exposure) and diabetes (a potentially time-varying/acquired exposure evaluated at baseline) using mixed-effects models with linear and nonlinear time specifications for both timescales. Results: Among APOE ε4 carriers, model-estimated memory scores at baseline (time on study timescale) or at each cohort’s median baseline age (current age timescale) were lower, and the average rate of decline was faster than among APOE ε4 noncarriers. Model-estimated memory scores at baseline or at median baseline age were generally similar across baseline diabetes status, with variability across cohorts in the diabetes-memory change association. In some cohorts, trends in diabetes-memory change associations differed in direction across timescales. Conclusions: Timescale was largely inconsequential for estimated effects of APOE genotype, but yielded differences in estimated diabetes effects, raising questions about the appropriate scale. The current age scale may be problematic because diabetes was measured heterogeneously in age across individuals, a common issue in aging cohorts. Our work demonstrates approaches to evaluate alternative timescales, including in multicohort analyses, and highlights potential implications for estimated exposure effects on cognitive change.

ABSTRACTImmune thrombotic thrombocytopenic purpura (iTTP) is characterized by microangiopathic hemolytic anemia, thrombocytopenia, and microvascular occlusion secondary to acquired ADAMTS13 deficiency. Contemporary data regarding iTTP treatment practices in the US, including the use of caplacizumab, are lacking. We aimed to characterize the demographics and therapies, including medications and apheresis practices, in patients with iTTP in the US. We retrospectively analyzed iTTP cases at 15 sites in the US that provide comprehensive care for patients with iTTP. The time‐period assessed was from January 1, 2017 to December 31, 2021. Our primary objective was to analyze data by iTTP episode, inclusive of initial episodes and relapses. A total of 390 iTTP episodes were reported for 280 unique individuals (187 females, 93 males). Thirty‐day mortality was 3.7% (14/374), and 6‐month mortality was 7.4% (27/367). TPE details were reported for 343 episodes, among which 261 underwent at least one procedure (median 6, IQR 3–11). Among the 261 episodes with at least one therapeutic plasma exchange (TPE) performed, 82.0% (214/261) used only plasma. Caplacizumab was used either alone or in combination with other agents in 43 (11.0%) episodes. Management strategies for iTTP remain varied across centers in the US, with a variety of combinations for TPE replacement fluids and therapeutic agents, as well as limited use of caplacizumab. Further research and standardization of treatment regimens may further reduce mortality in this condition.