Temporary Mechanical Circulatory Support in Sepsis-Associated Cardiogenic Shock With and Without Acute Myocardial Infarction.

OBJECTIVES: To describe the current use and outcomes of temporary mechanical circulatory support (MCS) in patients with sepsis-associated cardiogenic shocks with and without acute myocardial infarction (AMI) in the United States. DESIGN: Retrospective cohort study. SETTING: The National Inpatient Sample database from 2017 to 2019. PARTICIPANTS: Adult patients with sepsis-associated cardiogenic shock with and without AMI. INTERVENTIONS: Temporary MCSs, including intra-aortic balloon pump (IABP), percutaneous left ventricular assist device (pLVAD), and extracorporeal membrane oxygenation (ECMO). MEASUREMENTS AND MAIN RESULTS: Multivariate logistic regression analyses adjusting for patient characteristics, organ failures, and socioeconomic status. Although the uses of IABP and pLVAD were associated with significantly lower odds of in-hospital mortality in patients with sepsis-associated cardiogenic shock (IABP: adjusted odds ratio [aOR] 0.57, 95% CI 0.44-0.73, p < .001; pLVAD: aOR 0.66, 95% CI 0.45-0.98, p = .037), ECMO was not (aOR 1.51, 95% CI 0.93-2.45, p = 0.096). In the subgroup with AMI, temporary MCSs were not associated with significantly lower or higher odds of in-hospital mortality. In the subgroup without AMI, IABP was associated with significantly lower odds of in-hospital mortality (aOR 0.43, 95% CI 0.28-0.65, p < 0.001). CONCLUSIONS: Although temporary MCS is deemed to be a feasible option in sepsis-associated cardiogenic shock, the selection of the right patients whose shock is driven mainly by cardiogenic shock rather than septic shock, as represented by low cardiac output and high systemic vascular resistance, plays a critical role in the feasibility of this approach in the absence of clinical trials.

INVASIVE HEMODYNAMIC MONITORING WITH PULMONARY ARTERY CATHETER IN SEPSIS-ASSOCIATED CARDIOGENIC SHOCK.

ABSTRACT: Background: Both sepsis-induced cardiomyopathy and worsening of preexisting cardiac disease can contribute to circulatory shock in septic patients. The early use of pulmonary artery catheter (PAC) could play a pivotal role in the management of sepsis-associated cardiogenic shock. In this study, we aimed to evaluate the impact of early invasive hemodynamic monitoring with PAC in patients with sepsis-associated cardiogenic shock. Method: We performed a retrospective study using the National Inpatient Sample data from January 2017 to December 2019. The early use of PAC was defined as the use of PAC within 2 days from the admission. We performed the multivariable logistic regression analysis to investigate the association between the early use of PAC and in-hospital mortality in patients with sepsis-associated cardiogenic shock and sepsis without cardiogenic shock, respectively. Results: There was no difference in in-hospital mortality between PAC and no PAC groups in sepsis without cardiogenic shock (adjusted odds ratio [aOR] = 1.05, 95% confidence interval [CI] = 0.82-1.35, P = 691). On the other hand, the early use of PAC was independently associated with lower in-hospital mortality in patients with sepsis-associated cardiogenic shock (aOR = 0.58, 95% confidence interval [CI] = 0.46-0.72, P < 0.001). The use of PAC was also associated with increased use of mechanical circulatory support in those with sepsis-associated cardiogenic shock (aOR = 12.26, 95% CI = 9.37-16.03, P < 0.001). For patients with sepsis-associated cardiogenic shock, the use of PAC after 2 days of admission was associated with significantly higher in-hospital mortality and decreased use of mechanical circulatory support. Conclusion: The use of pulmonary artery catheters in sepsis-associated cardiogenic shock was associated with significantly lower in-hospital mortality and increased use of mechanical circulatory supports in patients with sepsis-associated cardiogenic shock.

Sleep orchestrates indices of local plasticity and global network stability in the human cortex.

Animals and humans spend on average one third of their lives in sleep, but its functions remain to be specified. Distinct lines of research propose that sleep promotes local strengthening of information-bearing synapses (plasticity) and global downscaling of synaptic strength (stability) in neural networks-prerequisites for adaptive behavior in a changing environment. However, the potential orchestration of these processes, particularly in humans, needs to be further characterized. Here, we use electrophysiological, behavioral, and molecular indices to noninvasively study cortical plasticity and network stability in humans. We observe indices of local strengthening of prior induced long-term potentiation-like plasticity (paired associative stimulation induced change in motor-evoked potential) and global network stabilization (homeostatic regulation of wake EEG theta activity) after brief periods of nonrapid eye movement sleep compared with wakefulness. The interplay of local sleep slow oscillations and spindle activity, previously related to synaptic refinements during sleep, is identified as a potential mechanism. Our findings are consistent with the notion that sleep-specific brain activity patterns reduce the plasticity-stability dilemma by orchestrating local plasticity and global stability of neural assemblies in the human cortex. Future studies are needed to further decipher the neural mechanisms underlying our indirect observations.

A Proteomic Characterization of Bordetella pertussis Clinical Isolates Associated with a California State Pertussis Outbreak.

Bordetella pertussis (Bp) is the etiologic agent of pertussis (whooping cough), a highly communicable infection. Although pertussis is vaccine preventable, in recent years there has been increased incidence, despite high vaccine coverage. Possible reasons for the rise in cases include the following: Bp strain adaptation, waning vaccine immunity, increased surveillance, and improved clinical diagnostics. A pertussis outbreak impacted California (USA) in 2010; children and preadolescents were the most affected but the burden of disease fell mainly on infants. To identify protein biomarkers associated with this pertussis outbreak, we report a whole cellular protein characterization of six Bp isolates plus the pertussis acellular vaccine strain Bp Tohama I (T), utilizing gel-free proteomics-based mass spectrometry (MS). MS/MS tryptic peptide detection and protein database searching combined with western blot analysis revealed three Bp isolates in this study had markedly reduced detection of pertactin (Prn), a subunit of pertussis acellular vaccines. Additionally, antibody affinity capture technologies were implemented using anti-Bp T rabbit polyclonal antisera and whole cellular proteins to identify putative immunogens. Proteome profiling could shed light on pathogenesis and potentially lay the foundation for reduced infection transmission strategies and improved clinical diagnostics.

A cell-based phenotypic assay to identify cardioprotective agents.

RATIONALE: Tissue ischemia/reperfusion (IR) injury underlies several leading causes of death such as heart-attack and stroke. The lack of clinical therapies for IR injury may be partly due to the difficulty of adapting IR injury models to high-throughput screening (HTS). OBJECTIVE: To develop a model of IR injury that is both physiologically relevant and amenable to HTS. METHODS AND RESULTS: A microplate-based respirometry apparatus was used. Controlling gas flow in the plate head space, coupled with the instrument's mechanical systems, yielded a 24-well model of IR injury in which H9c2 cardiomyocytes were transiently trapped in a small volume, rendering them ischemic. After initial validation with known protective molecules, the model was used to screen a 2000-molecule library, with post-IR cell death as an end point. Po2 and pH monitoring in each well also afforded metabolic data. Ten protective, detrimental, and inert molecules from the screen were subsequently tested in a Langendorff-perfused heart model of IR injury, revealing strong correlations between the screening end point and both recovery of cardiac function (negative, r2=0.66) and infarct size (positive, r2=0.62). Relationships between the effects of added molecules on cellular bioenergetics and protection against IR injury were also studied. CONCLUSIONS: This novel cell-based assay can predict either protective or detrimental effects on IR injury in the intact heart. Its application may help identify therapeutic or harmful molecules.

Synthesis of amino acid cofactor in cysteine dioxygenase is regulated by substrate and represents a novel post-translational regulation of activity.

Cysteine dioxygenase (CDO) catalyzes the conversion of cysteine to cysteinesulfinic acid and is important in the regulation of intracellular cysteine levels in mammals and in the provision of oxidized cysteine metabolites such as sulfate and taurine. Several crystal structure studies of mammalian CDO have shown that there is a cross-linked cofactor present in the active site of the enzyme. The cofactor consists of a thioether bond between the gamma-sulfur of residue cysteine 93 and the aromatic side chain of residue tyrosine 157. The exact requirements for cofactor synthesis and the contribution of the cofactor to the catalytic activity of the enzyme have yet to be fully described. In this study, therefore, we explored the factors necessary for cofactor biogenesis in vitro and in vivo and examined what effect cofactor formation had on activity in vitro. Like other cross-linked cofactor-containing enzymes, formation of the Cys-Tyr cofactor in CDO required a transition metal cofactor (Fe(2+)) and O(2). Unlike other enzymes, however, biogenesis was also strictly dependent upon the presence of substrate. Cofactor formation was also appreciably slower than the rates reported for other enzymes and, indeed, took hundreds of catalytic turnover cycles to occur. In the absence of the Cys-Tyr cofactor, CDO possessed appreciable catalytic activity, suggesting that the cofactor was not essential for catalysis. Nevertheless, at physiologically relevant cysteine concentrations, cofactor formation increased CDO catalytic efficiency by approximately 10-fold. Overall, the regulation of Cys-Tyr cofactor formation in CDO by ambient cysteine levels represents an unusual form of substrate-mediated feed-forward activation of enzyme activity with important physiological consequences.