Protocol for simultaneous isolation of high-quality and high-quantity cardiomyocytes and non-myocyte cells from adult rat hearts.

Isolating high-quality different cell types is a powerful approach for understanding cellular compositions and features in the heart, but it is challenging. The available protocols typically focus on isolating one or two cell types. Here, we present a protocol to simultaneously isolate high-quality and high-quantity cardiomyocytes and non-myocyte cells, including immune cells, from adult rat hearts. We describe steps for purifying cells using bovine serum albumin. We also detail procedures for viability analysis and cell type identification using fluorescence-activated cell sorting. For complete details on the use and execution of this protocol, please refer to Zhang et al.,1 Valkov et al.,2 Vang et al.,3 and Li et al.4.

Reduction in activity and abundance of mitochondrial electron transport chain supercomplexes in pulmonary hypertension-induced right ventricular dysfunction.

Pulmonary hypertension (PH) results in RV hypertrophy, fibrosis and dysfunction resulting in RV failure which is associated with impaired RV metabolism and mitochondrial respiration. Mitochondrial supercomplexes (mSC) are assemblies of multiple electron transport chain (ETC) complexes that consist of physically associated complex I, III and IV that may enhance respiration and lower ROS generation. The goal of this study was to determine if mSCs are reduced in RV dysfunction associated with PH. We induced PH in Sprague-Dawley rats by Sugen/Hypoxia (3 weeks) followed by normoxia (4 weeks). Control and PH rats were subjected to echocardiography, blue and clear native-PAGE to assess mSC abundance and activity, and cardiomyocyte isolation to assess mitochondrial reactive oxygen species (ROS). mSC formation was also assessed in explanted human hearts with and without RV dysfunction. RV activity of CI and CIV and abundance of CI, CIII and CIV in mitochondrial mSCs was severely reduced in PH rats compared to control. There were no differences in total CI or CIV activity or abundance in smaller ETC assemblies. There were no changes in both RV and LV of expression of representative ETC complex subunits. PAT, TAPSE and RV Wall thickness significantly correlated with CIV and CI activity in mSC, but not total CI and CIV activity in the RV. Consistent with reduced mSC activity, isolated PH RV myocytes had increased mitochondrial ROS generation compared to control. Reduced mSC activity was also demonstrated in explanted human RV tissue from patients undergoing cardiac transplant with RV dysfunction. The right atrial pressure/pulmonary capillary wedge pressure ratio (RAP/PCWP, an indicator of RV dysfunction) negatively correlated with RV mSC activity level. In conclusion, reduced assembly and activity of mitochondrial mSC is correlated with RV dysfunction in PH rats and humans with RV dysfunction.

Right ventricular stiffening and anisotropy alterations in pulmonary hypertension: Mechanisms and relations to function.

Aims: Pulmonary hypertension (PH) results in an increase in RV afterload, leading to RV dysfunction and failure. The mechanisms underlying maladaptive RV remodeling are poorly understood. In this study, we investigated the multiscale and mechanistic nature of RV free wall (RVFW) biomechanical remodeling and its correlations with RV function adaptations. Methods and Results: Mild and severe models of PH, consisting of hypoxia (Hx) model in Sprague-Dawley (SD) rats (n=6 each, Control and PH) and Sugen-hypoxia (SuHx) model in Fischer (CDF) rats (n=6 each, Control and PH), were used. Organ-level function and tissue-level stiffness and microstructure were quantified through in-vivo and ex-vivo measures, respectively. Multiscale analysis was used to determine the association between fiber-level remodeling, tissue-level stiffening, and organ-level dysfunction. Animal models with different PH severity provided a wide range of RVFW stiffening and anisotropy alterations in PH. Decreased RV-pulmonary artery (PA) coupling correlated strongly with stiffening but showed a weaker association with the loss of RVFW anisotropy. Machine learning classification identified the range of adaptive and maladaptive RVFW stiffening. Multiscale modeling revealed that increased collagen fiber tautness was a key remodeling mechanism that differentiated severe from mild stiffening. Myofiber orientation analysis indicated a shift away from the predominantly circumferential fibers observed in healthy RVFW specimens, leading to a significant loss of tissue anisotropy. Conclusion: Multiscale biomechanical analysis indicated that although hypertrophy and fibrosis occur in both mild and severe PH, certain fiber-level remodeling events, including increased tautness in the newly deposited collagen fibers and significant reorientations of myofibers, contributed to excessive biomechanical maladaptation of the RVFW leading to severe RV-PA uncoupling. Collagen fiber remodeling and the loss of tissue anisotropy can provide an improved understanding of the transition from adaptive to maladaptive remodeling. Translational perspective: Right ventricular (RV) failure is a leading cause of mortality in patients with pulmonary hypertension (PH). RV diastolic and systolic impairments are evident in PH patients. Stiffening of the RV wall tissue and changes in the wall anisotropy are expected to be major contributors to both impairments. Global assessments of the RV function remain inadequate in identifying patients with maladaptive RV wall remodeling primarily due to their confounded and weak representation of RV fiber and tissue remodeling events. This study provides novel insights into the underlying mechanisms of RV biomechanical remodeling and identifies the adaptive-to-maladaptive transition across the RV biomechanics-function spectrum. Our analysis dissecting the contribution of different RV wall remodeling events to RV dysfunction determines the most adverse fiber-level remodeling to RV dysfunction as new therapeutic targets to curtail RV maladaptation and, in turn, RV failure in PH.

Stiffening of the human proximal pulmonary artery with increasing age.

Adverse effects of large artery stiffening are well established in the systemic circulation; stiffening of the proximal pulmonary artery (PPA) and its sequelae are poorly understood. We combined in vivo (n = 6) with ex vivo data from cadavers (n = 8) and organ donors (n = 13), ages 18 to 89, to assess whether aging of the PPA associates with changes in distensibility, biaxial wall strain, wall thickness, vessel diameter, and wall composition. Aging exhibited significant negative associations with distensibility and cyclic biaxial strain of the PPA (p ≤ 0.05), with decreasing circumferential and axial strains of 20% and 7%, respectively, for every 10 years after 50. Distensibility associated directly with diffusion capacity of the lung (R2 = 0.71, p = 0.03). Axial strain associated with right ventricular ejection fraction (R2 = 0.76, p = 0.02). Aging positively associated with length of the PPA (p = 0.004) and increased luminal caliber (p = 0.05) but showed no significant association with mean wall thickness (1.19 mm, p = 0.61) and no significant differences in the proportions of mural elastin and collagen (p = 0.19) between younger (<50 years) and older (>50) ex vivo samples. We conclude that age-related stiffening of the PPA differs from that of the aorta; microstructural remodeling, rather than changes in overall geometry, may explain age-related stiffening.

Hemorrhagic Adverse Events of Transthoracic Needle Biopsy of the Lung in Patients with Pulmonary Hypertension: A Systematic Review and Meta-Analysis.

PURPOSE: To compare the risk of hemorrhagic adverse events of transthoracic needle biopsy (TTNB) such as pulmonary hemorrhage and hemoptysis between patients with pulmonary hypertension (PH) and patients without PH. MATERIALS AND METHODS: Database search and citation review of search results were performed for studies reporting frequency of hemorrhagic adverse events of TTNB in adult patients with evidence of PH compared with that in patients undergoing the procedure without evidence of PH. Random-effects meta-analysis was performed for both rates of pulmonary hemorrhage and hemoptysis. RESULTS: A total of 5 studies (encompassing 6,250 patients who underwent 6,684 biopsies) were included. All studies were retrospective and used computed tomography (CT) or echocardiography for identification of signs of PH. Biopsy-related pulmonary hemorrhage was diagnosed radiographically, and postbiopsy hemoptysis was diagnosed by documentation in the medical record. There were no differences found between patients with evidence of PH and those without regarding rates of pulmonary hemorrhage (odds ratio [OR], 1.12 [95% confidence interval {CI}, 0.85-1.47] in studies that used CT to define PH, and OR, 0.88 [95% CI 0.56-1.39] in studies that used echocardiography to define PH). There were also no differences in the rates of hemoptysis (OR, 0.95 [95% CI, 0.46-1.97]). CONCLUSIONS: A systematic review and meta-analysis of the literature did not demonstrate that patients with imaging evidence of PH undergoing TTNB had an increased risk of hemorrhagic adverse events.

Reduced exercise capacity occurs before intrinsic skeletal muscle dysfunction in experimental rat models of pulmonary hypertension.

Reduced exercise capacity in pulmonary hypertension (PH) significantly impacts quality of life. However, the cause of reduced exercise capacity in PH remains unclear. The objective of this study was to investigate whether intrinsic skeletal muscle changes are causative in reduced exercise capacity in PH using preclinical PH rat models with different PH severity. PH was induced in adult Sprague-Dawley (SD) or Fischer (CDF) rats with one dose of SU5416 (20 mg/kg) injection, followed by 3 weeks of hypoxia and additional 0-4 weeks of normoxia exposure. Control s rats were injected with vehicle and housed in normoxia. Echocardiography was performed to assess cardiac function. Exercise capacity was assessed by VO2 max. Skeletal muscle structural changes (atrophy, fiber type switching, and capillary density), mitochondrial function, isometric force, and fatigue profile were assessed. In SD rats, right ventricular systolic dysfunction is associated with reduced exercise capacity in PH rats at 7-week timepoint in comparison to control rats, while no changes were observed in skeletal muscle structure, mitochondrial function, isometric force, or fatigue profile. CDF rats at 4-week timepoint developed a more severe PH and, in addition to right ventricular dysfunction, the reduced exercise capacity in these rats is associated with skeletal muscle atrophy; however, mitochondrial function, isometric force, and fatigue profile in skeletal muscle remain unchanged. Our data suggest that cardiopulmonary impairments in PH are the primary cause of reduced exercise capacity, which occurs before intrinsic skeletal muscle dysfunction.

Transfer Learning-Based B-Line Assessment of Lung Ultrasound for Acute Heart Failure.

OBJECTIVE: B-lines assessed by lung ultrasound (LUS) outperform physical exam, chest radiograph, and biomarkers for the associated diagnosis of acute heart failure (AHF) in the emergent setting. The use of LUS is however limited to trained professionals and suffers from interpretation variability. The objective was to utilize transfer learning to create an AI-enabled software that can aid novice users to automate LUS B-line interpretation. METHODS: Data from an observational AHF LUS study provided standardized cine clips for AI model development and evaluation. A total of 49,952 LUS frames from 30 patients were hand scored and trained on a convolutional neural network (CNN) to interpret B-lines at the frame level. A random independent evaluation set of 476 LUS clips from 60 unique patients assessed model performance. The AI models scored the clips on both a binary and ordinal 0-4 multiclass assessment. RESULTS: A multiclassification AI algorithm had the best performance at the binary level when applied to the independent evaluation set, AUC of 0.967 (95% CI 0.965-0.970) for detecting pathologic conditions. When compared to expert blinded reviewer, the 0-4 multiclassification AI algorithm scale had a reported linear weighted kappa of 0.839 (95% CI 0.804-0.871). CONCLUSIONS: The multiclassification AI algorithm is a robust and well performing model at both binary and ordinal multiclass B-line evaluation. This algorithm has the potential to be integrated into clinical workflows to assist users with quantitative and objective B-line assessment for evaluation of AHF.

Ionic liquids: environmentally sustainable materials for energy conversion and storage applications.

Ionic liquids (ILs), often known as green designer solvents, have demonstrated immense application potential in numerous scientific and technological domains. ILs possess high boiling point and low volatility that make them suitable environmentally benign candidates for many potential applications. The more important aspect associated with ILs is that their physicochemical properties can be effectively changed for desired applications just by tuning the structure of the cationic and/or anionic part of ILs. Furthermore, these eco-friendly designer materials can function as electrolytes or solvents depending on the application. Owing to the distinctive properties such as low volatility, high thermal and electrochemical stability, and better ionic conductivity, ILs are nowadays immensely used in a variety of energy applications, particularly in the development of green and sustainable energy storage and conversion devices. Suitable ILs are designed for specific purposes to be used as electrolytes and/or solvents for fuel cells, lithium-ion batteries, supercapacitors (SCs), and solar cells. Herein, we have highlighted the utilization of ILs as unique green designer materials in Li-batteries, fuel cells, SCs, and solar cells. This review will enlighten the promising prospects of these unique, environmentally sustainable materials for next-generation green energy conversion and storage devices. Ionic liquids have much to offer in the field of energy sciences regarding fixing some of the world's most serious issues. However, most of the discoveries discussed in this review article are still at the laboratory research scale for further development. This review article will inspire researchers and readers about how ILs can be effectively applied in energy sectors for various applications as mentioned above.

Clinical predictors of right ventricular dysfunction and association with adverse outcomes in peripartum cardiomyopathy.

AIMS: We sought to identify factors associated with right ventricular (RV) dysfunction and elevated pulmonary artery systolic pressure (PASP) and association with adverse outcomes in peripartum cardiomyopathy (PPCM). METHODS AND RESULTS: We conducted a multi-centre cohort study to identify subjects with PPCM with the following criteria: left ventricular ejection fraction (LVEF) < 40%, development of heart failure within the last month of pregnancy or 5 months of delivery, and no other identifiable cause of heart failure with reduced ejection fraction. Outcomes included a composite of (i) major adverse events (need for extracorporeal membrane oxygenation, ventricular assist device, orthotopic heart transplantation, or death) or (ii) recurrent heart failure hospitalization. RV function was obtained from echocardiogram reports. In total, 229 women (1993-2017) met criteria for PPCM. Mean age was 32.4 ± 6.8 years, 28% were of African descent, 50 (22%) had RV dysfunction, and 38 (17%) had PASP ≥ 30 mmHg. After a median follow-up of 3.4 years (interquartile range 1.0-8.8), 58 (25%) experienced the composite outcome of adverse events. African descent, family history of cardiomyopathy, LVEF, and PASP were significant predictors of RV dysfunction. Using Cox proportional hazards models, we found that women with RV dysfunction were three times more likely to experience the adverse composite outcome: hazard ratio 3.21 (95% confidence interval: 1.11-9.28), P = 0.03, in a multivariable model adjusting for age, race, body mass index, preeclampsia, hypertension, diabetes, kidney disease, and LVEF. Women with PASP ≥ 30 mmHg had a lower probability of survival free from adverse events (log-rank P = 0.04). CONCLUSIONS: African descent and family history of cardiomyopathy were significant predictors of RV dysfunction. RV dysfunction and elevated PASP were significantly associated with a composite of major adverse cardiac events. This at-risk group may prompt closer monitoring or early referral for advanced therapies.

Proprotein convertase subtilisn/kexin type 9 inhibitors and small interfering RNA therapy for cardiovascular risk reduction: A systematic review and meta-analysis.

BACKGROUND: Atherosclerotic cardiovascular disease (ASCVD) is the leading cause of mortality worldwide. Atherosclerosis occurs due to accumulation of low-density lipoprotein cholesterol (LDL-c) in the arterial system. Thus, lipid lowering therapy is essential for both primary and secondary prevention. Proprotein convertase subtilisn/kexin type 9 (PCSK9) inhibitors (Evolocumab, Alirocumab) and small interfering RNA (siRNA) therapy (Inclisiran) have been demonstrated to lower LDL-c and ASCVD events in conjunction with maximally tolerated statin therapy. However, the degree of LDL-c reduction and the impact on reducing major adverse cardiac events, including their impact on mortality, remains unclear. OBJECTIVE: The purpose of this study is to examine the effects of PCSK9 inhibitors and small interfering RNA (siRNA) therapy on LDL-c reduction and major adverse cardiac events (MACE) and mortality by conducting a meta-analysis of randomized controlled trials. METHODS: Using Pubmed, Embase, Cochrane Library and clinicaltrials.gov until April 2023, we extracted randomized controlled trials (RCTs) of PCSK9 inhibitors (Evolocumab, Alirocumab) and siRNA therapy (Inclisiran) for lipid lowering and risk of MACE. Using random-effects models, we pooled the relative risks and 95% CIs and weighted least-squares mean difference in LDL-c levels. We estimated odds ratios with 95% CIs among MACE subtypes and all-cause mortality. Fixed-effect model was used, and heterogeneity was assessed using the I2 statistic. RESULTS: In all, 54 studies with 87,669 participants (142,262 person-years) met criteria for inclusion. LDL-c percent change was reported in 47 studies (n = 62,634) evaluating two PCSK9 inhibitors and siRNA therapy. Of those, 21 studies (n = 41,361) included treatment with Evolocumab (140mg), 22 (n = 11,751) included Alirocumab (75mg), and 4 studies (n = 9,522) included Inclisiran (284mg and 300mg). Compared with placebo, after a median of 24 weeks (IQR 12-52), Evolocumab reduced LDL-c by -61.09% (95% CI: -64.81, -57.38, p<0.01) and Alirocumab reduced LDL-c by -46.35% (95% CI: -51.75, -41.13, p<0.01). Inclisiran 284mg reduced LDL-c by -54.83% (95% CI: -59.04, -50.62, p = 0.05) and Inclisiran 300mg reduced LDL-c by -43.11% (95% CI: -52.42, -33.80, p = 0.01). After a median of 8 months (IQR 6-15), Evolocumab reduced the risk of myocardial infarction (MI), OR 0.72 (95% CI: 0.64, 0.81, p<0.01), coronary revascularization, 0.77 (95% CI: 0.70, 0.84, p<0.01), stroke, 0.79 (95% CI: 0.66, 0.94, p = 0.01) and overall MACE 0.85 (95% CI: 0.80, 0.89, p<0.01). Alirocumab reduced MI, 0.57 (0.38, 0.86, p = 0.01), cardiovascular mortality 0.35 (95% CI: 0.16, 0.77, p = 0.01), all-cause mortality 0.60 (95% CI: 0.43, 0.84, p<0.01), and overall MACE 0.35 (0.16, 0.77, p = 0.01). CONCLUSION: PCSK9 inhibitors (Evolocumab, Alirocumab) and siRNA therapy (Inclisiran) significantly reduced LDL-c by >40% in high-risk individuals. Additionally, both Alirocumab and Evolocumab reduced the risk of MACE, and Alirocumab reduced cardiovascular and all-cause mortality.

Echocardiographic Progression of Peak Tricuspid Regurgitant Velocity Among Medicare Beneficiaries.

BACKGROUND: Peak tricuspid regurgitant velocity (TRV) on transthoracic echocardiography (TTE) is a commonly obtained parameter and robust predictor of subsequent adverse clinical outcomes. OBJECTIVES: The purpose of this study was to determine the predictors and clinical significance of TRV progression. METHODS: We retrospectively linked consecutive outpatient TTE reports from our institution to 2005 to 2017 Medicare claims. Individuals with prior tricuspid surgery, endocarditis, tricuspid stenosis, missing TRV values, TTEs performed during inpatient hospitalization, or <2 TTEs were excluded. RESULTS: A total of 4,572 patients (mean age 67.8 ± 11.9 years, 50.4% female) received 13,273 TTEs over a median follow-up of 7.4 (IQR: 4.5-6.9) years. TRV increased by a mean of 0.23 (95% CI: 0.22 to 0.23 m/s/y, P < 0.001) (range, 0.01-0.80 m/s/y). Older age, depressed left ventricular ejection fraction, diabetes, hypertension, hyperlipidemia, atrial fibrillation, heart failure, and chronic kidney disease were associated with faster progression (all P < 0.05). Accounting for 23 demographic, clinical, and TTE variables, faster TRV progression was associated with a stepwise increased risk of all-cause mortality (TRV progression quartile 4 vs 1; adjusted HR: 2.17; 95% CI: 1.74-2.71; P < 0.001). Those with regression of TRV (n = 384 [8.4%]) had a lower mortality risk (adjusted HR: 0.40; 95% CI: 0.28-0.57; P < 0.001). CONCLUSIONS: In this large, multidecade study of Medicare beneficiaries with serial TTEs performed in the outpatient setting, the mean rate of TRV progression was 0.23 m/s/y. Older age, left heart disease, and adverse metabolic features were associated with faster progression. Faster progression was associated with a graded risk for all-cause mortality.

On the possibility of estimating myocardial fiber architecture from cardiac strains.

The myocardium is composed of a complex network of contractile myofibers that are organized in such a way as to produce efficient contraction and relaxation of the heart. The myofiber architecture in the myocardium is a key determinant of cardiac motion and the global or organ-level function of the heart. Reports of architectural remodeling in cardiac diseases, such as pulmonary hypertension and myocardial infarction, potentially contributing to cardiac dysfunction call for the inclusion of an architectural marker for an improved assessment of cardiac function. However, the in-vivo quantification of three-dimensional myo-architecture has proven challenging. In this work, we examine the sensitivity of cardiac strains to varying myofiber orientation using a multiscale finite-element model of the LV. Additionally, we present an inverse modeling approach to predict the myocardium fiber structure from cardiac strains. Our results indicate a strong correlation between fiber orientation and LV kinematics, corroborating that the fiber structure is a principal determinant of LV contractile behavior. Our inverse model was capable of accurately predicting the myocardial fiber range and regional fiber angles from strain measures. A concrete understanding of the link between LV myofiber structure and motion, and the development of non-invasive and feasible means of characterizing the myocardium architecture is expected to lead to advanced LV functional metrics and improved prognostic assessment of structural heart disease.

Improved right ventricular strain estimation in rats using anisotropic diffusion filtering.

Calculating cardiac strains through speckle tracking echocardiography (STE) has shown promise as prognostic markers linked to functional indices and disease outcomes. However, the presence of acoustic shadowing often challenges the accuracy of STE in small animals such as rodents. The shadowing arises due to the complex anatomy of rodents, with operator dexterity playing a significant role in image quality. The effects of the semi-transparent shadows are further exacerbated in right ventricular (RV) imaging due to the thinness and rapid motion of the RV free wall (RVFW). The movement of the RVFW across the shadows distorts speckle tracking and produces unnatural and non-physical strains. The objective of this study was to minimize the effects of shadowing on STE by distinguishing "out-of-shadow" motion and identifying speckles in and out of shadow. Parasternal 2D echocardiography was performed, and short-axis B-mode (SA) images of the RVFW were acquired for a rodent model of pulmonary hypertension (n = 1). Following image acquisition, a denoising algorithm using edge-enhancing anisotropic diffusion (EED) was implemented, and the ensuing effects on strain analysis were visualized using a custom STE pipeline. Speckles in the shadowed regions were identified through a correlation between the filtered image and the original acquisition. Thus, pixel movement across the boundary was identified by enhancing the distinction between the shadows and the cardiac wall, and non-physical strains were suppressed. The strains obtained through STE showed expected patterns with enhanced circumferential contractions in the central region of the RVFW in contrast to smaller and nearly uniform strains derived from the unprocessed images.

Long-term statin therapy is associated with severe coronary artery calcification.

BACKGROUND: Atherosclerosis and consequent risk of cardiovascular events or mortality can be accurately assessed by quantifying coronary artery calcium score (CACS) derived from computed tomography. HMG-CoA-reductase inhibitors (statins) are the primary pharmacotherapy used to reduce cardiovascular events, yet there is growing data that support statin use may increase coronary calcification. We set out to determine the likelihood of severe CACS in the context of chronic statin therapy. METHODS: We established a retrospective, case-control study of 1,181 U.S. veterans without coronary artery disease (CAD) from a single site, the Providence VA Medical Center. Duration of statin therapy for primary prevention was divided into 5-year categorical increments. The primary outcome was CACS derived from low-dose lung cancer screening computed tomography (LCSCT), stratified by CACs severity (none = 0; mild = 1-99; moderate = 100-399; and severe ≥400 AU). Statin duration of zero served as the referent control. Ordinal logistic regression analysis determined the association between duration of statin use and CACS categories. Proportional odds assumption was tested using likelihood ratio test. Atherosclerotic cardiovascular disease (ASCVD) risk score, body mass index, and CKD (glomerular filtration rate of <60 ml/min/1.73 m2) were included in the adjustment models. RESULTS: The mean age of the study population was 64.7±7.2 years, and 706 (60%) patients were prescribed a statin at baseline. Duration of statin therapy was associated with greater odds of having increased CACS (>0-5 years, OR: 1.71 [CI: 1.34-2.18], p<0.001; >5-10 years, OR: 2.80 [CI: 2.01-3.90], p<0.001; >10 years, OR: 5.30 [CI: 3.23-8.70], p<0.001), and the relationship between statin duration and CACS remained significant after multivariate adjustment (>0-5 years, OR: 1.49 [CI: 1.16-1.92], p = 0.002; >5-10 years, OR: 2.38 [CI: 1.7-3.35], p<0.001; >10 years, OR: 4.48 [CI: 2.7-7.43], p<0.001). CONCLUSIONS: Long-term use of statins is associated with increased likelihood of severe CACS in patients with significant smoking history. The use of CACS to interpret cardiovascular event risk may require adjustment in the context of chronic statin therapy.

Elevated Pulmonary Arterial Compliance Is Associated with Survival in Pulmonary Hypertension: Results from a Novel Network Medicine Analysis.

Rationale: Predictors of adverse outcome in pulmonary hypertension (PH) are well established; however, data that inform survival are lacking. Objectives: We aim to identify clinical markers and therapeutic targets that inform the survival in PH. Methods: We included data from patients with elevated mean pulmonary artery pressure (mPAP) diagnosed by right heart catheterization in the U.S. Veterans Affairs system (October 1, 2006-September 30, 2018). Network medicine framework was used to subgroup patients when considering an N of 79 variables per patient. The results informed outcome analyses in the discovery cohort and a sex-balanced validation right heart catheterization cohort from Vanderbilt University (September 24, 1998-December 20, 2013). Measurements and Main Results: From an N of 4,737 complete case patients with mPAP of 19-24 mm Hg, there were 21 distinct subgroups (network modules) (all-cause mortality range = 15.9-61.2% per module). Pulmonary arterial compliance (PAC) drove patient assignment to modules characterized by increased survival. When modeled continuously in patients with mPAP ⩾19 mm Hg (N = 37,744; age, 67.2 yr [range = 61.7-73.8 yr]; 96.7% male; median follow-up time, 1,236 d [range = 570-1,971 d]), the adjusted all-cause mortality hazard ratio was <1.0 beginning at PAC ⩾3.0 ml/mm Hg and decreased progressively to ∼7 ml/mm Hg. A protective association between PAC ⩾3.0 ml/mm Hg and mortality was also observed in the validation cohort (N = 1,514; age, 60.2 yr [range = 49.2-69.1 yr]; 48.0% male; median follow-up time, 2,485 d [range = 671-3,580 d]). The association was strongest in patients with precapillary PH at the time of catheterization, in whom 41% (95% confidence interval, 0.55-0.62; P < 0.001) and 49% (95% confidence interval, 0.38-0.69; P < 0.001) improvements in survival were observed for PAC ⩾3.0 versus <3.0 ml/mm Hg in the discovery and validation cohorts, respectively. Conclusions: These data identify elevated PAC as an important parameter associated with survival in PH. Prospective studies are warranted that consider PAC ⩾3.0 ml/mm Hg as a therapeutic target to achieve through proven interventions.

A retrospective analysis of epidemiology, clinical features of envenomation, and in-patient management of snakebites in a model secondary hospital of Assam, North-east India.

Assam, a Northeastern State of India, is inhabited by several venomous snake species causing substantial morbidity and mortality. The data on the epidemiology of snakebites and their management is underreported in this region. Hence, a secondary health-based retrospective study was carried out at Demow Model Hospital, Sivasagar, Assam, to evaluate the clinical and epidemiological profile of snakebite cases reported in this rural hospital and their management. Snakebites occurring between April 2018 to August 2022 were reviewed based on socio-demographic details of the patient, clinical symptoms, and treatment using a standard questionnaire. Out of the 1011 registered snakebite cases, 139 patients (13.7%) counted for venomous bites, among which 92 patients (66.19%) accounted for viper bites (green pit viper and Salazar's pit viper), and 30 patients (21.5%) were bitten by elapid snakes (Indian monocled Cobra, banded krait, and greater/lesser black krait). A maximum number of snakebite cases (80.5%) were reported from the interior rural villages and documented from July to September (51.3%). Elapid snake envenomed patients, except one, were successfully treated with commercial antivenom, neostigmine, and glycopyrrolate. Because commercial polyvalent antivenom against "Big Four" venomous snakes of India showed poor neutralization of pit-vipers envenomation; therefore, pit-viper bite patients were treated with repurposed drugs magnesium sulfate and glycerin compression dressing. Adverse serum reactions were reported only in 3 (11.1%) cases. The preventive measures and facilities adopted at the Demow Model Hospital significantly reduce snakebite death and morbidity; therefore, they can be s practised across various states in India as a prototype.

Pragmatic evaluation of events and benefits of lipid lowering in older adults (PREVENTABLE): Trial design and rationale.

Whether initiation of statins could increase survival free of dementia and disability in adults aged ≥75 years is unknown. PREVENTABLE, a double-blind, placebo-controlled randomized pragmatic clinical trial, will compare high-intensity statin therapy (atorvastatin 40 mg) with placebo in 20,000 community-dwelling adults aged ≥75 years without cardiovascular disease, disability, or dementia at baseline. Exclusion criteria include statin use in the prior year or for >5 years and inability to take a statin. Potential participants are identified using computable phenotypes derived from the electronic health record and local referrals from the community. Participants will undergo baseline cognitive testing, with physical testing and a blinded lipid panel if feasible. Cognitive testing and disability screening will be conducted annually. Multiple data sources will be queried for cardiovascular events, dementia, and disability; survival is site-reported and supplemented by a National Death Index search. The primary outcome is survival free of new dementia or persisting disability. Co-secondary outcomes are a composite of cardiovascular death, hospitalization for unstable angina or myocardial infarction, heart failure, stroke, or coronary revascularization; and a composite of mild cognitive impairment or dementia. Ancillary studies will offer mechanistic insights into the effects of statins on key outcomes. Biorepository samples are obtained and stored for future study. These results will inform the benefit of statins for increasing survival free of dementia and disability among older adults. This is a pioneering pragmatic study testing important questions with low participant burden to align with the needs of the growing population of older adults.

Glutaminase inhibition in combination with azacytidine in myelodysplastic syndromes: Clinical efficacy and correlative analyses.

Malignancies can become reliant on glutamine as an alternative energy source and as a facilitator of aberrant DNA methylation, thus implicating glutaminase (GLS) as a potential therapeutic target. We demonstrate preclinical synergy of telaglenastat (CB-839), a selective GLS inhibitor, when combined with azacytidine (AZA), in vitro and in vivo, followed by a phase Ib/II study of the combination in patients with advanced MDS. Treatment with telaglenastat/AZA led to an ORR of 70% with CR/mCRs in 53% patients and a median overall survival of 11.6 months. scRNAseq and flow cytometry demonstrated a myeloid differentiation program at the stem cell level in clinical responders. Expression of non-canonical glutamine transporter, SLC38A1, was found to be overexpressed in MDS stem cells; was associated with clinical responses to telaglenastat/AZA and predictive of worse prognosis in a large MDS cohort. These data demonstrate the safety and efficacy of a combined metabolic and epigenetic approach in MDS.