Predictors and Impact of Prolonged Vasoplegia After Continuous-Flow Left Ventricular Assist Device Implantation.

Background: Vasoplegia after cardiac surgery is associated with adverse outcomes. However, the clinical effects of vasoplegia and the significance of its duration after continuous-flow left ventricular assist device (CF-LVAD) implantation are less known. Objectives: This study aimed to identify predictors of and outcomes from transient vs prolonged vasoplegia after CF-LVAD implantation. Methods: The study was a retrospective review of consecutive patients who underwent CF-LVAD implantation between January 1, 2005, and December 31, 2017. Vasoplegia was defined as the presence of all of the following: mean arterial pressure ≤65 mm Hg, vasopressor (epinephrine, norepinephrine, vasopressin, or dopamine) use for >6 hours within the first 24 hours postoperatively, cardiac index ≥2.2 L/min/m2 and systemic vascular resistance <800 dyne/s/cm5, and vasodilatory shock not attributable to other causes. Prolonged vasoplegia was defined as that lasting 12 to 24 hours; transient vasoplegia was that lasting 6 to <12 hours. Patient characteristics, outcomes, and risk factors were analyzed. Results: Of the 600 patients who underwent CF-LVAD implantation during the study period, 182 (30.3%) developed vasoplegia. Mean patient age was similar between the vasoplegia and no-vasoplegia groups. Prolonged vasoplegia (n = 78; 13.0%), compared with transient vasoplegia (n = 104; 17.3%), was associated with greater 30-day mortality (16.7% vs 5.8%; P = 0.02). Risk factors for prolonged vasoplegia included preoperative dialysis and elevated body mass index. Conclusions: Compared with vasoplegia overall, prolonged vasoplegia was associated with worse survival after CF-LVAD implantation. Treatment to avoid or minimize progression to prolonged vasoplegia may be warranted.

Depressive symptoms are associated with clinical outcomes in heart failure with reduced ejection fraction.

AIMS: The objective of this study was to examine associations between elevated depressive symptoms and increased risk of adverse clinical events patients with heart failure and reduced ejection fraction (HFrEF), as well as the potential contribution of health behaviours. METHODS AND RESULTS: One hundred forty-two men and women with HFrEF were enrolled through heart failure (HF) clinics and followed over time. At baseline and 6 months, depressive symptoms were assessed by the Beck Depression Inventory-II (BDI-II) and HFrEF disease activity by B-type natriuretic peptide (BNP). The Self-Care of Heart Failure Index (SCHFI) was used to assess HF self-care behaviours. Proportional hazards regression models assessed the contribution of depressive symptoms and HFrEF disease biomarkers on death or cardiovascular hospitalization. Over a median follow-up period of 4 years, 42 patients (30%) died, and 84 (60%) had cardiovascular hospitalizations. A 10-point higher baseline BDI-II score was associated with a 35% greater risk of death or cardiovascular hospitalization. Higher baseline BDI-II scores were associated with poorer HF self-care maintenance behaviours (R = -0.30, P < 0.001) and fewer daily steps (R = -0.19, P = 0.04), suggesting that elevated depressive symptoms may diminish important health behaviours. Increases in plasma BNP over 6 months were associated with worse outcomes. Changes in BDI-II and plasma BNP over 6 months were positively related (R = 0.25, P = 0.004). CONCLUSIONS: This study confirms that elevated depressive symptoms are associated with an increased likelihood of adverse clinical outcomes in patients with HFrEF. Poor health behaviours may contribute to the adverse association of elevated depressive symptoms with the increased hazard of adverse clinical outcomes.

Neural cell-types and circuits linking thermoregulation and social behavior.

Understanding how social and affective behavioral states are controlled by neural circuits is a fundamental challenge in neurobiology. Despite increasing understanding of central circuits governing prosocial and agonistic interactions, how bodily autonomic processes regulate these behaviors is less resolved. Thermoregulation is vital for maintaining homeostasis, but also associated with cognitive, physical, affective, and behavioral states. Here, we posit that adjusting body temperature may be integral to the appropriate expression of social behavior and argue that understanding neural links between behavior and thermoregulation is timely. First, changes in behavioral states-including social interaction-often accompany changes in body temperature. Second, recent work has uncovered neural populations controlling both thermoregulatory and social behavioral pathways. We identify additional neural populations that, in separate studies, control social behavior and thermoregulation, and highlight their relevance to human and animal studies. Third, dysregulation of body temperature is linked to human neuropsychiatric disorders. Although body temperature is a "hidden state" in many neurobiological studies, it likely plays an underappreciated role in regulating social and affective states.

Strong immunogenicity & protection in mice with PlaCCine: A COVID-19 DNA vaccine formulated with a functional polymer.

DNA- based vaccines have demonstrated the potential as a safe and effective modality. PlaCCine, a DNA-based vaccine approach described subsequently relies on a synthetic DNA delivery system and is independent of virus or device. The synthetic functionalized polymer combined with DNA demonstrated stability over 12 months at 4C and for one month at 25C. Transfection efficiency compared to naked DNA increased by 5-15-fold in murine skeletal muscle. Studies of DNA vaccines expressing spike proteins from variants D614G (pVAC15), Delta (pVAC16), or a D614G + Delta combination (pVAC17) were conducted. Mice immunized intramuscular injection (IM) with pVAC15, pVAC16 or pVAC17 formulated with functionalized polymer and adjuvant resulted in induction of spike-specific humoral and cellular responses. Antibody responses were observed after one immunization. And endpoint IgG titers increased to greater than 1x 105 two weeks after the second injection. Neutralizing antibodies as determined by a pseudovirus competition assay were observed following vaccination with pVAC15, pVAC16 or pVAC17. Spike specific T cell immune responses were also observed following vaccination and flow cytometry analysis demonstrated the cellular immune responses included both CD4 and CD8 spike specific T cells. The immune responses in vaccinated mice were maintained for up to 14 months after vaccination. In an immunization and challenge study of K18 hACE2 transgenic mice pVAC15, pVAC16 and pVAC17 induced immune responses lead to decreased lung viral loads by greater than 90 % along with improved clinical score. These findings suggest that PlaCCine DNA vaccines are effective and stable and further development against emerging SARS-CoV-2 variants is warranted.

Sex Disparities in Left Ventricular Assist Device Implantation: Delayed Presentation and Worse Right Heart Failure.

We explored whether women undergo continuous-flow left ventricular assist device (CF-LVAD) implantation in later stages of heart failure (HF) than men, evidenced by worse preoperative right HF (RHF). We also compared two propensity models with and without preoperative RHF to assess its effect on outcomes. INTERMACS was queried from July 2008 to December 2017. Propensity model 1 matched men and women on age ≥50 years, HF etiology, body surface area, INTERMACS class, comorbidities, device strategy, temporary mechanical circulatory support, and device type. Model 2 included these variables plus LV end-diastolic diameter, right atrial pressure/pulmonary capillary wedge pressure, pulmonary artery pulsatility index, and right ventricular ejection fraction. The primary outcome was all-cause mortality. Secondary outcomes comprise RHF, rehospitalization, renal dysfunction, stroke, and device malfunction. In model 1, characteristics were comparable between 3,195 women and 3,195 men, except women more often had preoperative RHF and postoperative right VAD support and had worse 1 year and overall survival. In model 2, after propensity matching for additional risk factors for preoperative RHF, 1,119 women and 1,119 men had comparable post-LVAD implant RVAD use and survival. These findings suggest that women present more often with biventricular failure and after implantation have higher RHF and mortality rates.

De novo design of high-affinity binders of bioactive helical peptides.

Many peptide hormones form an α-helix on binding their receptors1-4, and sensitive methods for their detection could contribute to better clinical management of disease5. De novo protein design can now generate binders with high affinity and specificity to structured proteins6,7. However, the design of interactions between proteins and short peptides with helical propensity is an unmet challenge. Here we describe parametric generation and deep learning-based methods for designing proteins to address this challenge. We show that by extending RFdiffusion8 to enable binder design to flexible targets, and to refining input structure models by successive noising and denoising (partial diffusion), picomolar-affinity binders can be generated to helical peptide targets by either refining designs generated with other methods, or completely de novo starting from random noise distributions without any subsequent experimental optimization. The RFdiffusion designs enable the enrichment and subsequent detection of parathyroid hormone and glucagon by mass spectrometry, and the construction of bioluminescence-based protein biosensors. The ability to design binders to conformationally variable targets, and to optimize by partial diffusion both natural and designed proteins, should be broadly useful.

Clinical Outcomes of Single-Stage Revision Anterior Cruciate Ligament Reconstruction Using a Fast-Setting Bone Graft Substitute.

Revision anterior cruciate ligament reconstruction (ACLR) can be achieved in a single-stage or two-stage approach. Single-stage revisions have several advantages, including one less operation, decreased cost, and a quicker recovery for patients. Revision ACLR can be complicated by malpositioned or dilated bone tunnels, which makes a single-stage revision more challenging or sometimes necessitates a two-stage approach. The use of fast-setting bone graft substitutes (BGS) has been described in recent literature as a strategy to potentially help address this problem in the setting of single-stage revision ACLR. The aim of this study was to evaluate patient-reported clinical outcomes of patients who have undergone single-stage revision ACLR using fast-setting BGS to address prior malpositioned or dilated tunnels. A retrospective review was conducted of the first nine consecutive patients who had undergone single-stage revision ACLR using a fast-setting BGS by a single surgeon between May 2017 and February 2020 with a minimum of 2-year follow-up. Patient-reported clinical outcomes, including the International Knee Documentation Committee (IKDC) questionnaire, the Tegner Lysholm Knee Scoring Scale, patient satisfaction questions, and the need for additional surgery were evaluated for this group between 26 and 49 months postoperative. Of the nine patients eligible for inclusion, eight patients (88.9%) were evaluated, and one was lost to follow-up. At an average follow-up of 37.9 months (range: 27.8-55.7), the mean postoperative IKDC score was 75.0 ± 11.3, and the mean postoperative Tegner Lysholm Knee Score was 83.0 ± 17.6. None of the patients required additional revision surgery or experienced construct failure at the time of follow-up. Seven of eight respondents (87.5%) had their preoperative expectations met with the surgery, and 100% of patients stated they would have the surgery again. Single-stage revision ACLR using fast-setting BGS showed overall positive clinical outcomes for this pilot group of patients at a minimum 2-year follow-up. In select revision scenarios, these materials may be a valuable option to allow the filling of defects without compromising fixation or clinical outcomes.

Substrates and Cyclic Peptide Inhibitors of the Oligonucleotide-Activated Sirtuin 7.

The sirtuins are NAD+ -dependent lysine deacylases, comprising seven isoforms (SIRT1-7) in humans, which are involved in the regulation of a plethora of biological processes, including gene expression and metabolism. The sirtuins share a common hydrolytic mechanism but display preferences for different ϵ-N-acyllysine substrates. SIRT7 deacetylates targets in nuclei and nucleoli but remains one of the lesser studied of the seven isoforms, in part due to a lack of chemical tools to specifically probe SIRT7 activity. Here we expressed SIRT7 and, using small-angle X-ray scattering, reveal SIRT7 to be a monomeric enzyme with a low degree of globular flexibility in solution. We developed a fluorogenic assay for investigation of the substrate preferences of SIRT7 and to evaluate compounds that modulate its activity. We report several mechanism-based SIRT7 inhibitors as well as de novo cyclic peptide inhibitors selected from mRNA-display library screening that exhibit selectivity for SIRT7 over other sirtuin isoforms, stabilize SIRT7 in cells, and cause an increase in the acetylation of H3 K18.

Association of Depression Symptoms and Biomarkers of Risk on Clinical Outcomes in HFrEF.

BACKGROUND: Prior studies have demonstrated an association of depression with adverse clinical outcomes in patients with HFrEF, but the possible mechanisms responsible for the association are not unserstood. METHODS: 142 men and women with HFrEF were enrolled through HF clinics and followed over time. At baseline and 6-months, depression was assessed by the Beck Depression Inventory (BDI-II) and disease activity by B-type natriuretic peptide (BNP). Proportional Hazards Regression Models assessed the contribution of depressive symptoms and HFrEF disease biomarkers on death or cardiovascular hospitalization. RESULTS: Over a median follow-up period of 4 years, 42 patients (30%) died, and 84 (60%) had cardiovascular hospitalizations. A 10-point higher baseline BDI-II score was associated with a 35% higher hazard of death or cardiovascular hospitalization. Greater baseline BDI-II scores were associated with poorer HF self-care maintenance (R=-0.30, p<0.001) and fewer daily steps (R=-0.19, p=0.04), suggesting that depression may adversely affect important health behaviors. Increases in plasma BNP over 6 months were associated with worse outcomes. Changes in BDI-II score and plasma BNP over 6 months were positively correlated (R=0.25, p=0.004). CONCLUSIONS: This study underscores the importance of elevated depression symptoms and their association with an increased likelihood of adverse clinical outcomes in patients with HFrEF. Health behaviors may play a greater role than direct biobehavioral pathways in the adverse effects of depression on the HF disease trajectory and resultant clinical outcomes.

Consensus-based framework for evaluating data modernization initiatives: the case of cancer registration and electronic reporting.

As part of its data modernization initiative (DMI), the Centers for Disease Control and Prevention, Division of Cancer Prevention and Control is testing and implementing innovative solutions to improve cancer surveillance data quality and timeliness. We describe a consensus-based effort to create a framework to guide the evaluation of cancer surveillance modernization efforts by addressing specific context, processes, and costs related to cancer registration. We drew on prior theories, consulted with experts, and sought feedback from cancer registry staff. We developed the cancer surveillance systems, context, outcomes, and process evaluation (CS-SCOPE) framework to explain the ways in which cancer registry data quality, timeliness, and efficiency are impacted by external and internal contextual factors and interrelated process and content factors. The framework includes implementation measures to understand acceptability of process changes along with outcome measures to assess DMI initiation and ongoing sustainability. The framework's components and structures can be tailored for use in other DMI evaluations.

Utilization Rates of SGLT2 Inhibitors Among Patients With Type 2 Diabetes, Heart Failure, and Atherosclerotic Cardiovascular Disease: Insights From the Department of Veterans Affairs.

BACKGROUND: Multiple clinical trials have demonstrated significant cardiovascular benefit with use of sodium-glucose cotransporter-2 (SGLT2) inhibitors in patients with type 2 diabetes (T2DM) and heart failure (HF) irrespective of ejection fraction. There are limited data evaluating real-world prescription and practice patterns of SGLT2 inhibitors. OBJECTIVES: The authors sought to assess utilization rates and facility-level variation in the use among patients with established atherosclerotic cardiovascular disease (ASCVD), HF, and T2DM using data from the nationwide Veterans Affairs health care system. METHODS: The authors included patients with established ASCVD, HF, and T2DM seen by a primary care provider between January 1, 2020, and December 31, 2020. They assessed the use of SGLT2 inhibitors and the facility-level variation in their use. Facility-level variation was computed using median rate ratios, a measure of likelihood that 2 random facilities differ in use of SGLT2 inhibitors. RESULTS: Among 105,799 patients with ASCVD, HF, and T2DM across 130 Veterans Affairs facilities, 14.6% received SGLT2 inhibitors. Patients receiving SGLT2 inhibitors were younger men with higher hemoglobin A1c and estimated glomerular filtration rate and were more likely to have HF with reduced ejection fraction and ischemic heart disease. There was significant facility-level variation of SGLT2 inhibitor use, with an adjusted median rate ratio of 1.55 (95% CI: 1.46-1.64), indicating a 55% residual difference in SGLT2 inhibitor use among similar patients with ASCVD, HF, and T2DM receiving care at 2 random facilities. CONCLUSIONS: Utilization rates of SGLT2 inhibitors are low in patients with ASCVD, HF, and T2DM, with high residual facility-level variation. These findings suggest opportunities to optimize SGLT2 inhibitor use to prevent future adverse cardiovascular events.

Impact of the 2018 UNOS Heart Transplant Policy Changes on Patient Outcomes.

In 2018, the United Network for Organ Sharing implemented a 6-tier allocation policy to replace the prior 3-tier system. Given increasing listings of critically ill candidates for heart transplantation and lengthening waitlist times, the new policy aimed to better stratify candidates by waitlist mortality, shorten waiting times for high priority candidates, add objective criteria for common cardiac conditions, and further broaden sharing of donor hearts. There have been significant shifts in cardiac transplantation practices and patient outcomes following the implementation of the new policy, including changes in listing practices, waitlist time and mortality, transplant donor characteristics, post-transplantation outcomes, and mechanical circulatory support use. This review aims to highlight emerging trends in United States heart transplantation practice and outcomes following the implementation of the 2018 United Network for Organ Sharing heart allocation policy and to address areas for future modification.

Acoustic modes of a spherical thin-walled tank for liquid propellant mass gauging: Theory and experiment.

Acoustic response of a thin-walled spherical flight tank filled with water is explored theoretically and experimentally as a testbed for an application of Weyl's law to the problem of mass-gauging propellants in zero-gravity in space. Weyl's law relates the mode counting function of a resonator to its volume and can be used to infer the volume of liquid in a tank from the tank's acoustic response. One of the challenges of applying Weyl's law to real tanks is to account for the boundary conditions which are neither Neumann nor Dirichlet. We show that the liquid modes in a thin-walled spherical tank correspond to the spectrum of a slightly larger spherical tank with infinitely compliant wall (Dirichlet boundary condition), where Weyl's law can be applied directly. The mass of the liquid enclosed by this "effective" tank's wall is found to equal the actual mass of the liquid plus the mass of the wall. This finding is generalized to thin-walled tanks and liquid configurations of arbitrary shapes and thus provides a calculable correction factor for the propellant mass inferred using Weyl's law with Dirichlet boundary conditions.