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Soluble Immune Checkpoint Protein and Lipid Network Associations with All-Cause Mortality Risk: Trans-Omics for Precision Medicine (TOPMed) Program.

Adverse cardiovascular events are emerging with the use of immune checkpoint therapies in oncology. Using datasets in the Trans-Omics for Precision Medicine program (Multi-Ethnic Study of Atherosclerosis, Jackson Heart Study [JHS], and Framingham Heart Study), we examined the association of immune checkpoint plasma proteins with each other, their associated protein network with high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C), and the association of HDL-C- and LDL-C-associated protein networks with all-cause mortality risk. Plasma levels of LAG3 and HAVCR2 showed statistically significant associations with mortality risk. Colocalization analysis using genome wide-association studies of HDL-C or LDL-C and protein quantitative trait loci from JHS and the Atherosclerosis Risk in Communities identified TFF3 rs60467699 and CD36 rs3211938 variants as significantly colocalized with HDL-C; in contrast, none colocalized with LDL-C. The measurement of plasma LAG3, HAVCR2, and associated proteins plus targeted genotyping may identify patients at increased mortality risk.

Journal Article

Significant variation in the performance of DNA methylation predictors across data preprocessing and normalization strategies.

BACKGROUND: DNA methylation (DNAm)-based predictors hold great promise to serve as clinical tools for health interventions and disease management. While these algorithms often have high prediction accuracy, the consistency of their performance remains to be determined. We therefore conduct a systematic evaluation across 101 different DNAm data preprocessing and normalization strategies and assess how each analytical strategy affects the consistency of 41 DNAm-based predictors. RESULTS: Our analyses are conducted in a large EPIC DNAm array dataset from the Jackson Heart Study (N = 2053) that included 146 pairs of technical replicate samples. By estimating the average absolute agreement between replicate pairs, we show that 32 out of 41 predictors (78%) demonstrate excellent consistency when appropriate data processing and normalization steps are implemented. Across all pairs of predictors, we find a moderate correlation in performance across analytical strategies (mean rho = 0.40, SD = 0.27), highlighting significant heterogeneity in performance across algorithms. Successful or unsuccessful removal of technical variation furthermore significantly impacts downstream phenotypic association analysis, such as all-cause mortality risk associations. CONCLUSIONS: We show that DNAm-based algorithms are sensitive to technical variation. The right choice of data processing strategy is important to achieve reproducible estimates and improve prediction accuracy in downstream phenotypic association analyses. For each of the 41 DNAm predictors, we report its degree of consistency and provide the best performing analytical strategy as a guideline for the research community. As DNAm-based predictors become more and more widely used, our work helps improve their performance and standardize their implementation.

DNA Methylation

Admixture-mapping analysis reveals genetic determinants of the human plasma proteome.

Protein profiling and genetic findings can be integrated to define the genetic architecture of the circulating proteome in chronic diseases. Most self-identified African American (AA) individuals have both African and European genetic ancestry. Admixture mapping can detect genomic association regions in which causal variants exist with substantial differences in allele frequency or effect sizes between genetic ancestries. We performed admixture mapping of the circulating proteome in 1,989 participants from the Jackson Heart Study (JHS), investigating the relation of local African ancestry within genomic regions with levels of circulating proteins. We conditioned protein-local ancestry association models on variants previously found to be associated with those proteins in genome-wide association studies (GWASs). We replicated findings in 196 AA participants from the Multi-Ethnic Study of Atherosclerosis (MESA). 62 proteins were associated with local African ancestry. 21 of 62 remained statistically significant after conditioning on protein-associated variants observed in previous GWASs. 48 of 54 available protein-local ancestry associations were replicated in the MESA. Proteins associated with local African ancestry included chemokines, factors associated with vascular biology and inflammation, and other biologically interesting proteins. Admixture associations unexplained by previously reported protein-associated variants in conditional analysis suggest the existence of causal variants missed by standard GWAS techniques.

Aged

Standardized aerobic and anaerobic exercise: differential effects on intraocular tension, blood pH, and lactate.

The effects of standardized aerobic and anaerobic exercise intensities on intraocular tension, blood lactate, and pH were studied. Intraocular tension decreased rapidly at all exercise intensities. The absolute lowest level of intraocular tension reached with aerobic and anaerobic exercise levels varied by only 1.5 mm. Hg and this difference was not statistically significant. Blood lactate and pH changes correlated with intraocular tension changes at anaerobic exercise levels, but not at aerobic exercise levels. These findings associated with aerobic exercise have not been previously reported. It is suggested that parameters other than the decrease in blood pH and the increase in blood lactate are responsible for most of the decrease in intraocular tension associated with dynamic exercise.

Aerobiosis

Relationship between packed cell volume, platelets, and platelet survival in red blood cell-hypertransfused mice.

In this study we have measured platelet and megakaryocyte concentration, blood volume, and platelet survival of mice after RBC hypertransfusion to PCVs of 62% to 90%. The platelet concentration of mice with PCVs up to 75% was decreased by up to one half. At higher PCVs a more severe thrombocytopenia developed, with platelet concentrations decreased to less than 10% of baseline in approximately one half of the mice. Blood volumes of the hypertransfused mice were increased up to twofold. Megakaryocyte concentrations were normal or increased. Platelet survival in mice with PCVs less than 75% was normal but was sharply decreased for mice with higher PCVs. The decrease in platelet concentration at moderately elevated PCVs may be explained by hemodilution in the larger blood volume. However, hemodilution alone cannot explain the severe thrombocytopenia at higher PCVs. The presence of decreased platelet survival with normal or increased megakaryocyte concentrations in this latter group suggests that the severe thrombocytopenia is the result of more rapid platelet destruction. In summary, elevation of the PCV by RBC hypertransfusion produces thrombocytopenia. The severity of the thrombocytopenia and the mechanisms involved in producing it change abruptly when the PCV exceeds 75%. These findings should be considered in interpretations of the influence of RBC hypertransfusion on hematopoiesis and in clinical and experimental studies of thrombopoiesis in polycythemic subjects.

Animals

Comparison of anesthesia with diazepam and ketamine vs. morphine in patients undergoing heart-valve replacement.

Because of its analgesic and amnesic effects, ketamine has potential advantages as a primary agent for patients undergoing open-heart surgery. However, the undesirable positive inotropic and chronotropic effects associated with ketamine have deterred its use. Diazepam pretreatment appears to block these unwanted effects. Sixteen randomly selected patients were given a combination of diazepam, 0.4 mg/kg, followed by ketamine, 2 mg/kg, and nitrous oxide, 50%. The authors compared the circulatory responses to induction, intubation, and operation with those obtained in a matched group of patients who received morphine, 3 mg/kg, and nitrous oxide, 50%. All patients underwent mitral- or aortic-valve replacement. Circulatory responses were not significantly different between the two groups. In both groups, heart rate, mean arterial blood pressure, and rate-pressure product increased significantly with intubation of the trachea, incision of the skin, and sternotomy. The incidences of hypertension, hypotension, and arrhythmias, and the need for inotropic drugs were not significantly different between the two groups. No intraoperative awareness occurred in either group. It is concluded that diazepam-ketamine anesthesia is a satisfactory alternative to morphine anesthesia for patient undergoing heart-valve replacement.

Adult

Total cerebral ischemia: a new model system for the study of post-cardiac arrest brain damage.

The pathophysiology of post-cardiac arrest brain damage is not well understood. Many of the model systems presently used to study global ischemia have serious limitations. A new model system for total cerebral ischemia (TCI), using aortic and inferior vena caval occlusion balloons, is described. This model system produces verifiable TCI and avoids surgical invasion of the thorax or the use of vasoactive drugs. It does not impede cerebral venous return and protects the cardiopulmonary system from damage. This model system can be used to study the efficacy of various therapeutic interventions following a standardized CNS global ischemic insult.

Animals

Comparison of atenolol with propranolol in the treatment of angina pectoris with special reference to once daily administration of atenolol.

Fourteen patients with angina pectoris completed a double blind trial of atenolol 25 mg, 50 mg, and 100 mg twice daily and propranolol 80 mg thrice daily. In comparison with placebo, all active treatments significantly reduced anginal attacks, consumption of glyceryl trinitrate, resting and exercise heart rate, resting and exercise systolic blood pressure, and significantly prolonged exercise time. There was no significant difference between the effects of propranolol and atenolol. Nine patients completed a further trial comparing atenolol given once or twice daily. Both regimens were effective and there was no significant difference between the reductions in anginal attacks, glyceryl trinitrate consumption, systolic blood pressure, or heart rate. Twenty-four-hour ambulatory electrocardiograms showed that atenolol consistently reduced heart rate throughout the 24-hour period whether given once or twice daily. Atenolol is a potent antianginal agent which, in most patients, is likely to be effective once daily.

Adult

The effects of sodium cromoglycate on lung irritant receptors and left ventricular cardiac receptors in the anaesthetized dog.

1 The time from the injection of sodium cromoglycate 10 to 50 mug/kg into a saphenous vein, the cervical carotid arteries, the left ventricle and the aortic arch, to the onset of reflex hypotension has been measured in anaesthetized dogs. The shortest latency was 16.9 s on injection of sodium cromoglycate into the left ventricle.2 Instillation of 2% lignocaine into the pericardium of an anaesthetized dog blocked the reflex hypotensive response to sodium cromoglycate (10 to 50 mug/kg i.v.), and also prevented sodium cromoglycate (100 mug/kg) from reversing reflex bronchoconstriction induced by inhalation of an aerosol of histamine.3 The effect of sodium cromoglycate (100 mug/kg i.v.) on resting discharge and histamine-induced discharge (20 mug/kg i.v.) of five lung irritant receptors in five anaesthetized dogs has been studied. Sodium cromoglycate (100 mug/kg i.v.) did not affect the resting discharge of these receptors or their ability to respond to histamine.4 Sodium cromoglycate (100 mug/kg i.v.) increased the rate of discharge of three receptors found in the endocardium of the left ventricle of the canine heart. A solution of sodium cromoglycate (0.1%) was applied topically to one receptor and its rate of discharge was increased.5 It is suggested that in the dog, sodium cromoglycate produces reflex hypotension and reverses histamine-induced reflex bronchoconstriction by activating receptors in the left ventricle of the heart.

Action Potentials

Comparison of ketmine with the combination of ketamine and xylazine for effective anesthesia in the rhesus monkey (Macaca mulatta).

The addition of xylazine to ketamine hydrochloride was found to enhance analgesia, anesthesia, and muscle relaxation in rhesus monkeys. At 0.10 ml/kg body weight, this combination provided adequate anesthesia for such procedures as cisternal puncture, lumbar spinal puncture, insertion of urinary catheters, finger amputations, and tattooing. The combination of ketamine and xylazine did depress the heart rate, respiration rate, and body temperature more than the administration of ketamine alone. The period of anesthesia also was prolonged, but the monkeys regained consciousness more rapidly at the end of the anesthetic period.

Anesthesia

Systems genetics approaches model the heritable architecture of polyendocrine metabolic ovarian syndrome.

Polyendocrine metabolic ovarian syndrome (PMOS), formerly known as polycystic ovary syndrome (PCOS), is the most common endocrine disorder in women and is closely associated with complex diseases such as cardiovascular disease and type 2 diabetes. However, the mechanistic links between PMOS and its comorbidities remain poorly understood. Here, we present an integrative systems genetics platform that leverages genetic diversity in both mice and humans to dissect the drivers of PMOS and its associated complications. This framework uncovered conserved genetic and environmental factors underlying PMOS, identified susceptible cell types and organs, and elucidated mechanisms linking PMOS to subsequent pathologies. For instance, we showed that increased ovarian area contributes to both PMOS susceptibility and ovarian cancer progression, while specific ovary-heart signaling circuits modulate cardiac function with aging. We further identified ovarian SF3B1-mediated alternative splicing as a key mechanistic link between PMOS and metabolic traits. Pharmacologic inhibition of SF3B1 in mice reduced circulating testosterone, insulin, and glucose levels as well as fat mass expansion. Transcriptomics analysis of ovaries from mice and experiments using human cell lines localized these effects to exon skipping events in granulosa cells. Together, this study offers a mechanistic framework for modeling the diversity of PMOS pathologies and uncovers SF3B1-mediated splicing as a link between ovary function and systemic metabolism.

Female

Haemodynamic effects of atenolol in patients with coronary artery disease.

The haemodynamic effects of atenolol, a new cardioselective beta-blocking agent, have been studied at rest in 8 patients with coronary artery disease. The drug was administered intravenously in cumulative doses of 0.03, 0.06, and 0.12 mg/kg body weight. A significant decrease in heart rate was associated with a fall in cardiac output. However, this cardiac output fall was not entiely rate dependent, since stroke volume fell significantly both during spontaneous sinus rhythm and when heart rate was maintained constant by atrial pacing. A dose related and significant reduction occurred in left ventricular dP/dt max without significant change in left ventricular filling pressure or mean aortic pressure. Total peripheral resistance at rest rose after atenolol. The haemodynamic findings more closely resemble those which follow intravenous propranolol than those after intravenous practolol in a similar group of patients. These actions of atenolol suggest that it may be a useful agent in the treatment of patients with angina pectoris.

Adult

Acetate fails to reverse myocardial depression in dogs anesthetized with halothane.

Sodium acetate has been shown to reverse the myocardial depression induced by halothane in vitro. The biochemical basis for this restoration of contractility has been located in the glycolytic pathway. The present study was designed to determine whether this antagonistic property of acetate also occurs in vivo. Dogs autonomically blocked with guanethidine, phenoxybenzamine, and atropine were sequentially anesthetized with halothane in O2 and N2O-O2-succinylcholine in a random pattern. All animals were given sodium acetate IV in amounts adequate to produce pharmacologically active levels. Myocardial performance was measured by LVdP/dtmax, LVPDP/dt/KPmax, and Vmax. Halothane effected a significant depression of these myocardial parameters. Acetate did not reverse this depressant effect of halothane. Acetate, a well-established peripheral vascular vasodilator, did decrease left ventricular and aortic pressures.

Acetates

Detection of cytokine release syndrome using wearables and cytokine profiling following CAR-T therapy for myeloma.

BACKGROUNDChimeric antigen receptor T-cell (CAR-T) therapies have revolutionized treatment for relapsed/refractory multiple myeloma (RRMM). However, cytokine release syndrome (CRS), a common and potentially severe complication, requires inpatient monitoring, limiting access and increasing costs. Wearable devices could support outpatient CAR-T delivery, but feasibility for CRS detection versus standard care remains unproven.METHODSWe conducted a prospective, single-center observational pilot study to assess the feasibility of using wearable devices for monitoring vital signs and detecting CRS. Thirty patients receiving idecabtagene vicleucel (ide-cel) or ciltacabtagene autoleucel (cilta-cel) were enrolled; 25 with sufficient monitoring data were evaluable. Sensors collected skin and axillary temperature, oxygen saturation, respiratory and heart rate, and motion. Peripheral blood cytokines were analyzed pre- and postinfusion using a multiplex proteomic platform. The primary outcome was feasibility, assessed by CRS detection sensitivity and specificity; secondary outcomes included adherence, lead time, and performance of models integrating wearable and cytokine data.RESULTSCRS occurred in 20 of 25 patients. The best-performing wearable model detected 18 or 20 CRS episodes with a sensitivity of 0.72 (mean 0.75; 95% CI 0.60-0.91) and a specificity of 0.80 (mean 0.76; 95% CI 0.68-0.84), and a median lead time of 7:00 hours before nursing recognition. Median adherence during high-risk periods was 71%. Cytokine changes paralleled temperature elevations, and IFN-γ emerged as a consistent biomarker.CONCLUSIONWearable devices are feasible for early CRS detection and may support outpatient CAR-T care. Larger outpatient studies are warranted.TRIAL REGISTRATIONThis study did not meet the criteria for ClinicalTrials.gov registration.

Humans