Current Trends for 4D Space-Time Topology for Semantic Flow Segmentation

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The Erythrocyte Sedimentation Rate and Its Relation to Cell Shape and Rigidity of Red Blood Cells from Chorea-Acanthocytosis Patients in an Off-Label Treatment with Dasatinib

Background: Chorea-acanthocytosis (ChAc) is a rare hereditary neurodegenerative disease with deformed red blood cells (RBCs), so-called acanthocytes, as a typical marker of the disease. Erythrocyte sedimentation rate (ESR) was recently proposed as a diagnostic biomarker. To date, there is no treatment option for affected patients, but promising therapy candidates, such as dasatinib, a Lyn-kinase inhibitor, have been identified. Methods: RBCs of two ChAc patients during and after dasatinib treatment were characterized by the ESR, clinical hematology parameters and the 3D shape classification in stasis based on an artificial neural network. Furthermore, mathematical modeling was performed to understand the contribution of cell morphology and cell rigidity to the ESR. Microfluidic measurements were used to compare the RBC rigidity between ChAc patients and healthy controls. Results: The mechano-morphological characterization of RBCs from two ChAc patients in an off-label treatment with dasatinib revealed differences in the ESR and the acanthocyte count during and after the treatment period, which could not directly be related to each other. Clinical hematology parameters were in the normal range. Mathematical modeling indicated that RBC rigidity is more important for delayed ESR than cell shape. Microfluidic experiments confirmed a higher rigidity in the normocytes of ChAc patients compared to healthy controls. Conclusions: The results increase our understanding of the role of acanthocytes and their associated properties in the ESR, but the data are too sparse to answer the question of whether the ESR is a suitable biomarker for treatment success, whereas a correlation between hematological and neuronal phenotype is still subject to verification

Extracellular ATP Induces Vascular Inflammation and Atherosclerosis via Purinergic Receptor y 2 in Mice

Objective - A solid body of evidence supports a role of extracellular ATP and its P2 receptors in innate and adaptive immunity. It promotes inflammation as a danger signal in various chronic inflammatory diseases. Thus, we hypothesize contribution of extracellular ATP and its receptor P2Y 2 in vascular inflammation and atherosclerosis. Approach and Results - Extracellular ATP induced leukocyte rolling, adhesion, and migration in vivo as assessed by intravital microscopy and in sterile peritonitis. To test the role of extracellular ATP in atherosclerosis, ATP or saline as control was injected intraperitoneally 3× a week in low-density lipoprotein receptor -/- mice consuming high cholesterol diet. Atherosclerosis significantly increased after 16 weeks in ATP-treated mice (n=13; control group, 0.26 mm2; ATP group, 0.33 mm2; P=0.01). To gain into the role of ATP-receptor P2Y 2 in ATP-induced leukocyte recruitment, ATP was administered systemically in P2Y 2 -deficient or P2Y 2 -competent mice. In P2Y 2 -deficient mice, the ATP-induced leukocyte adhesion was significantly reduced as assessed by intravital microscopy. P2Y 2 expression in atherosclerosis was measured by real-time polymerase chain reaction and immunohistochemistry and demonstrates an increased expression mainly caused by influx of P2Y 2 -expressing macrophages. To investigate the functional role of P2Y 2 in atherogenesis, P2Y 2 -deficient low-density lipoprotein receptor -/- mice consumed high cholesterol diet. After 16 weeks, P2Y 2 -deficient mice showed significantly reduced atherosclerotic lesions with decreased macrophages compared with P2Y 2 -competent mice (n=11; aortic arch: control group, 0.25 mm 2; P2Y 2 -deficient, 0.14 mm2; P=0.04). Mechanistically, atherosclerotic lesions from P2Y 2 -deficient mice expressed less vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 RNA. Conclusions - We show that extracellular ATP induces vascular inflammation and atherosclerosis via activation of P2Y 2.Fil: Stachon, Peter. Albert Ludwigs University of Freiburg; AlemaniaFil: Geis, Serjosha. Albert Ludwigs University of Freiburg; AlemaniaFil: Peikert, Alexander. Albert Ludwigs University of Freiburg; AlemaniaFil: Heidenreich, Adrian. Albert Ludwigs University of Freiburg; AlemaniaFil: Anto Michel, Nathaly. Albert Ludwigs University of Freiburg; AlemaniaFil: Üenal, Fatih. Albert Ludwigs University of Freiburg; AlemaniaFil: Hoppe, Natalie. Albert Ludwigs University of Freiburg; AlemaniaFil: Dufner, Bianca. Albert Ludwigs University of Freiburg; AlemaniaFil: Schulte, Lisa. Albert Ludwigs University of Freiburg; AlemaniaFil: Marchini, Timoteo Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Bioquímica y Medicina Molecular. Universidad de Buenos Aires. Facultad Medicina. Instituto de Bioquímica y Medicina Molecular; ArgentinaFil: Cicko, Sanja. Albert Ludwigs University of Freiburg; AlemaniaFil: Korcan Ayata, Cemil. Albert Ludwigs University of Freiburg; AlemaniaFil: Zech, Andreas. Albert Ludwigs University of Freiburg; AlemaniaFil: Wolf, Dennis. Albert Ludwigs University of Freiburg; AlemaniaFil: Hilgendorf, Ingo. Albert Ludwigs University of Freiburg; AlemaniaFil: Willecke, Florian. Albert Ludwigs University of Freiburg; AlemaniaFil: Reinöhl, Jochen. Albert Ludwigs University of Freiburg; AlemaniaFil: von zur Muhlen, Constantin. Albert Ludwigs University of Freiburg; AlemaniaFil: Bode, Christoph. Albert Ludwigs University of Freiburg; AlemaniaFil: Idzko, Marco. Albert Ludwigs University of Freiburg; AlemaniaFil: Zirlik, Andreas. Albert Ludwigs University of Freiburg; Alemani

Evaluation of automated airway morphological quantification for assessing fibrosing lung disease

Abnormal airway dilatation, termed traction bronchiectasis, is a typical feature of idiopathic pulmonary fibrosis (IPF). Volumetric computed tomography (CT) imaging captures the loss of normal airway tapering in IPF. We postulated that automated quantification of airway abnormalities could provide estimates of IPF disease extent and severity. We propose AirQuant, an automated computational pipeline that systematically parcellates the airway tree into its lobes and generational branches from a deep learning based airway segmentation, deriving airway structural measures from chest CT. Importantly, AirQuant prevents the occurrence of spurious airway branches by thick wave propagation and removes loops in the airway-tree by graph search, overcoming limitations of existing airway skeletonisation algorithms. Tapering between airway segments (intertapering) and airway tortuosity computed by AirQuant were compared between 14 healthy participants and 14 IPF patients. Airway intertapering was significantly reduced in IPF patients, and airway tortuosity was significantly increased when compared to healthy controls. Differences were most marked in the lower lobes, conforming to the typical distribution of IPF-related damage. AirQuant is an open-source pipeline that avoids limitations of existing airway quantification algorithms and has clinical interpretability. Automated airway measurements may have potential as novel imaging biomarkers of IPF severity and disease extent

Longitudinal trajectories in renal function before and after heart failure hospitalization among patients with HFpEF in the PARAGON‐HF trial

Aims: Worsening renal function may impact long-term outcomes in heart failure (HF). However, little is known about the longitudinal trajectories in renal function in relation to the HF hospitalization or how this high-risk clinical event impacts renal outcomes. Methods and Results: In PARAGON-HF, we evaluated the association between recency of prior HF hospitalization (occurring pre-randomization) and subsequent first renal composite outcome: (1) time to ≥50% decline in eGFR ; (2) development of end stage renal disease (ESRD); or (3) death attributable to renal causes. 2,306 (48.1%) patients had a history of prior HF hospitalization. Incident rates of the renal outcome were highest in those most recently hospitalized and decreased with longer time from last hospitalization. Treatment effect on the renal outcome of sacubitril/valsartan vs. valsartan was similar between patients with (HR 0.43; 95% CI: 0.26 to 0.75) and without (HR 0.63; 95% CI: 0.33 to 1.18; Pinteraction = 0.39) a prior history of HF hospitalization and appeared consistent regardless of timing of prior hospitalization for HF (Pinteraction =0.39). Serial eGFR measurements leading up to and after a HF hospitalization (occurring during the study period) and estimated eGFR trajectories using repeated measures regression models with restricted cubic splines were also examined. Patients experiencing a post-randomization HF hospitalization had a significant decline in eGFR prior to hospitalization while patients without HF hospitalization experienced a relatively stable eGFR trajectory (p<0.001). A change in the rate of decline of eGFR trajectory was observed 12-months preceding a HF hospitalization, and continued in the post-discharge window to 12 months following hospitalization. Conclusions: HF hospitalization denotes increased risk for kidney disease progression which continues following recovery from HF decompensation in patients with HF with preserved ejection fraction

Effects of sacubitril/valsartan versus valsartan on renal function in patients with and without diabetes and heart failure with preserved ejection fraction: insights from PARAGON‐HF

Aims: Diabetes is associated with a faster rate of renal function decline in patients with heart failure (HF). Sacubitril/valsartan attenuates the deterioration of renal function to a greater extent in patients with diabetes and HF with reduced ejection fraction compared with renin–angiotensin system inhibitors alone. We assessed whether the same may be true in HF with preserved ejection fraction (HFpEF). Methods and results: In the PARAGON-HF trial in patients with HF and left ventricular ejection fraction of ≥45% (n = 4796), we characterized the effects of sacubitril/valsartan on changes in estimated glomerular filtration rate (eGFR) over a period of 192 weeks, and on the pre-specified renal composite outcome (eGFR reduction of ≥50%, end-stage renal disease, or death attributable to renal causes) in patients with (n = 2388) and without diabetes (n = 2408). The decline in eGFR was greater in patients with diabetes than in those without (−2.6 vs. −1.7 ml/min/1.73 m2 per year, p < 0.001), regardless of treatment assignment. Sacubitril/valsartan attenuated decline in eGFR similarly in patients with (−2.2 vs. −2.9 ml/min/1.73 m2 per year, p = 0.001) and without diabetes (−1.5 vs. −2.0 ml/min/1.73 m2 per year, p = 0.006) (pinteraction for difference in eGFR slopes = 0.40). Compared with valsartan, sacubitril/valsartan reduced the renal composite outcome similarly in patients without diabetes (hazard ratio [HR] 0.42, 95% confidence interval [CI] 0.19–0.91) and those with diabetes (HR 0.54, 95% CI 0.33–0.89; pinteraction = 0.59), as well as across a range of baseline glycated haemoglobin (pinteraction = 0.71). Conclusion: Sacubitril/valsartan, compared with valsartan, attenuates the decline of eGFR and reduces clinically relevant kidney events similarly among patients with HFpEF with and without diabetes

Association of dapagliflozin vs placebo with individual Kansas City Cardiomyopathy Questionnaire components in patients with heart failure with mildly reduced or preserved ejection fraction

Importance: Dapagliflozin has been shown to improve overall health status based on aggregate summary scores of the Kansas City Cardiomyopathy Questionnaire (KCCQ) in patients with heart failure (HF) with mildly reduced or preserved ejection fraction enrolled in the Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure (DELIVER) trial. A comprehensive understanding of the responsiveness of individual KCCQ items would allow clinicians to better inform patients on expected changes in daily living with treatment. Objective: To examine the association of dapagliflozin treatment with changes in individual components of the KCCQ. Design, Setting, and Participants: This is a post hoc exploratory analysis of DELIVER, a randomized double-blind placebo-controlled trial conducted at 353 centers in 20 countries from August 2018 to March 2022. KCCQ was administered at randomization and 1, 4, and 8 months. Scores of individual KCCQ components were scaled from 0 to 100. Eligibility criteria included symptomatic HF with left ventricular ejection fraction greater than 40%, elevated natriuretic peptide levels, and evidence of structural heart disease. Data were analyzed from November 2022 to February 2023. Main Outcomes and Measures: Changes in the 23 individual KCCQ components at 8 months. Interventions: Dapagliflozin, 10 mg, once daily or placebo. Results: Baseline KCCQ data were available for 5795 of 6263 randomized patients (92.5%) (mean [SD] age, 71.5 [9.5] years; 3344 male [57.7%] and 2451 female [42.3%]). Dapagliflozin was associated with larger improvements in almost all KCCQ components at 8 months compared with placebo. The most significant improvements with dapagliflozin were observed in frequency of lower limb edema (difference, 3.2; 95% CI, 1.6-4.8; P < .001), sleep limitation by shortness of breath (difference, 3.0; 95% CI, 1.6-4.4; P < .001), and limitation in desired activities by shortness of breath (difference, 2.8; 95% CI, 1.3-4.3; P < .001). Similar treatment patterns were observed in longitudinal analyses integrating data from months 1, 4, and 8. Higher proportions of patients treated with dapagliflozin experienced improvements, and fewer had deteriorations across most individual components. Conclusions and Relevance: In this study of patients with HF with mildly reduced or preserved ejection fraction, dapagliflozin was associated with improvement in a broad range of individual KCCQ components, with the greatest benefits in domains related to symptom frequency and physical limitations. Potential improvements in specific symptoms and activities of daily living might be more readily recognizable and easily communicated to patients. Trial Registration: ClinicalTrials.gov Identifier: NCT03619213

Dapagliflozin in patients with heart failure and previous myocardial infarction: A participant‐level pooled analysis of DAPA-HF and DELIVER

Aims Patients with heart failure (HF) and history of myocardial infarction (MI) face a higher risk of disease progression and clinical events. Whether sodium–glucose cotransporter 2 inhibitors may modify clinical trajectory in such individuals remains incompletely understood. Methods and results The DAPA-HF and DELIVER trials compared dapagliflozin with placebo in patients with symptomatic HF with left ventricular ejection fraction (LVEF) ≤40% and > 40%, respectively. In this pooled participant-level analysis, we assessed efficacy and safety outcomes by history of MI. The primary outcome in both trials was the composite of cardiovascular death or worsening HF. Of the total of 11 007 patients, 3731 (34%) had a previous MI and were at higher risk of the primary outcome across the spectrum of LVEF in covariate-adjusted models (hazard ratio [HR] 1.12, 95% confidence interval [CI] 1.02–1.24). Dapagliflozin reduced the risk of the primary outcome to a similar extent in patients with (HR 0.83, 95% CI 0.72–0.96) and without previous MI (HR 0.76, 95% CI 0.68–0.85; pinteraction = 0.36), with consistent benefits on key secondary outcomes as well. Serious adverse events did not occur more frequently with dapagliflozin, irrespective of previous MI. Conclusion History of MI confers increased risks of adverse cardiovascular outcomes in patients with HF across the LVEF spectrum, even among those with preserved ejection fraction. Dapagliflozin consistently and safely reduces the risk of cardiovascular death or worsening HF, regardless of previous MI

Homomorphic Encryption for Finite Automata

We describe a somewhat homomorphic GSW-like encryption scheme, natively encrypting matrices rather than just single elements. This scheme offers much better performance than existing homomorphic encryption schemes for evaluating encrypted (nondeterministic) finite automata (NFAs). Differently from GSW, we do not know how to reduce the security of this scheme to LWE, instead we reduce it to a stronger assumption, that can be thought of as an inhomogeneous variant of the NTRU assumption. This assumption (that we term iNTRU) may be useful and interesting in its own right, and we examine a few of its properties. We also examine methods to encode regular expressions as NFAs, and in particular explore a new optimization problem, motivated by our application to encrypted NFA evaluation. In this problem, we seek to minimize the number of states in an NFA for a given expression, subject to the constraint on the ambiguity of the NFA

The State of the Art in Topology-based Visualization of Unsteady Flow

Vector fields are a common concept for the representation of many different kinds of flow phenomena in science and engineering. Methods based on vector field topology are known for their convenience for visualizing and analyzing steady flows, but a counterpart for unsteady flows is still missing. However, a lot of good and relevant work aiming at such a solution is available. We give an overview of previous research leading towards topologybased and topology-inspired visualization of unsteady flow, pointing out the different approaches and methodologies involved as well as their relation to each other, taking classical (i.e., steady) vector field topology as our starting point. Particularly, we focus on Lagrangian methods, space-time domain approaches, local methods, and stochastic and multi-field approaches. Furthermore, we illustrate our review with practical examples for the different approaches