Effects of clinical depression on left ventricular dysfunction in patients with acute coronary syndrome.

Depression is associated with heart failure independent of traditional cardiovascular disease risk factors. Enhanced platelet activation has been suggested as a potential mechanism and has been associated with negative inotropic effects that can affect left ventricular ejection fraction (LVEF). We examined 131 consecutive acute coronary syndrome (ACS) patients to assess whether depression increased the risk for developing LV dysfunction, and to determine the effects of platelet serotonin signaling in this relationship. Major depression was assessed using the Structured Clinical Interview and depressive symptoms were measured using the Beck Depression Inventory (BDI), with BDI ≥ 10 defined as abnormal. LV dysfunction was defined as LVEF ≤ 45%. Platelet serotonin response was measured by serotonin augmented platelet aggregation and platelet serotonin receptor density. Mean age of ACS participants was 59 years, 78.6% male and 74.0% Caucasian. 34.4% of patients had a reduced LVEF ≤ 45% on presentation. Almost half (47.0%) of patients had BDI ≥ 10 and 18.0% had major depressive disorder. Platelet serotonin response was found to be augmented in depressed patients with low LVEF compared to depressed patients with normal LVEF (p < 0.020). However, the presence of LV dysfunction was found to be similar in both depressed (32.3%) and non-depressed (36.2%) patients (p = 0.714). This suggests alternative factors contribute to poor cardiovascular outcomes in depressed patients that are independent of LV function in post ACS patients.

Top five considerations for improving outcomes in black patients with heart failure: A guide for primary care clinicians.

Black patients develop heart failure at younger ages and have worse outcomes such as higher mortality rates compared to other racial and ethnic groups in the United States. Despite significant recent improvements in heart failure medical therapy, these worse outcomes have persisted. Multiple reasons have been provided to explain the situation, including but not limited to higher baseline cluster of cardiovascular risk factors amongst Black patients, inadequate use of heart failure guideline directed medical therapy and delayed referral for advanced heart failure therapies and interventions. Strategic interventions considering social and structural determinants of health, addressing structural inequalities/ bias, implementation of quality improvement programs, early diagnosis and prevention are critically needed to bridge the racial/ ethnic disparities gap and improve longevity of Black patients with heart failure. In this review, we propose evidence-based solutions that provide a framework for the primary care physician addressing these challenges to engender equity in treatment allocation and improve outcomes for all patients with heart failure.

Clinical outcomes and echocardiographic characteristics between African American and Caucasian patients with acute pulmonary embolism.

BACKGROUND: Despite socioeconomic disparities, no association between clinical presentation and poor outcomes explains a higher mortality in African Americans with pulmonary embolism (PE). The objective is to identify the co-morbidities and echocardiographic characteristics associated with increased mortality in African American patients. METHODS: This is a cross-sectional study of Caucasian or African American patients with PE diagnosed between October 2015 and December 2017 at University of Maryland Medical Center. The outcomes were in-hospital death, length of stay, and bleeding. RESULTS: There were 303 African Americans and 343 Caucasians. Caucasians were older (p = 0.007), males (p = 0.01) with history of coronary artery revascularization (CABG (p = 0.001), coronary stents (p = 0.001)), trauma (p = 0.007), and/or recent surgeries (p = 0.0001). African Americans exhibited higher rates of diabetes (p = 0.01), chronic kidney disease (p = 0.0005), and smoking (p = 0.04). Severity of PE was similar between groups and there was no difference in clot burden size. African Americans had more right ventricular strain on Computer Tomography (p = 0.001) and echocardiogram (p = 0.004); also, underfilled left ventricles (p = 0.02) and higher right ventricular systolic pressures (p = 0.001). There was no difference in hospital mortality (7.1% vs. 7.9%, p = 0.71), length of stay (13.1 ± 16.7 vs 12.8 ± 14.9, p = 0.80) and bleeding (9.0% vs.8.3%. p = 0.72). Mortality was higher in African Americans who received advanced therapies (3.8% vs. 18.8%, p = 0.02). The risk of death increased with age (OR 1.04; 95%CI 1.020-1.073) and with advanced therapies (OR 2.43; 95%CI 1.029-5.769). CONCLUSIONS: Differences in co-morbidities, radiologic findings, and echocardiographic characteristics that may contribute to higher mortality in African American patients, specifically those receiving advanced therapies.

Selective 13C labeling of nucleotides for large RNA NMR spectroscopy using an E. coli strain disabled in the TCA cycle.

Escherichia coli (E. coli) is an ideal organism to tailor-make labeled nucleotides for biophysical studies of RNA. Recently, we showed that adding labeled formate enhanced the isotopic enrichment at protonated carbon sites in nucleotides. In this paper, we show that growth of a mutant E. coli strain DL323 (lacking succinate and malate dehydrogenases) on (13)C-2-glycerol and (13)C-1,3-glycerol enables selective labeling at many useful sites for RNA NMR spectroscopy. For DL323 E. coli grown in (13)C-2-glycerol without labeled formate, all the ribose carbon atoms are labeled except the C3' and C5' carbon positions. Consequently the C1', C2' and C4' positions remain singlet. In addition, only the pyrimidine base C6 atoms are substantially labeled to ~96% whereas the C2 and C8 atoms of purine are labeled to ~5%. Supplementing the growth media with (13)C-formate increases the labeling at C8 to ~88%, but not C2. Not unexpectedly, addition of exogenous formate is unnecessary for attaining the high enrichment levels of ~88% for the C2 and C8 purine positions in a (13)C-1,3-glycerol based growth. Furthermore, the ribose ring is labeled in all but the C4' carbon position, such that the C2' and C3' positions suffer from multiplet splitting but the C5' position remains singlet and the C1' position shows a small amount of residual C1'-C2' coupling. As expected, all the protonated base atoms, except C6, are labeled to ~90%. In addition, labeling with (13)C-1,3-glycerol affords an isolated methylene ribose with high enrichment at the C5' position (~90%) that makes it particularly attractive for NMR applications involving CH(2)-TROSY modules without the need for decoupling the C4' carbon. To simulate the tumbling of large RNA molecules, perdeuterated glycerol was added to a mixture of the four nucleotides, and the methylene TROSY experiment recorded at various temperatures. Even under conditions of slow tumbling, all the expected carbon correlations were observed, which indicates this approach of using nucleotides obtained from DL323 E. coli will be applicable to high molecular weight RNA systems.

Growth of wildtype and mutant E. coli strains in minimal media for optimal production of nucleic acids for preparing labeled nucleotides.

Since RNAs lie at the center of most cellular processes, there is a need for synthesizing large amounts of RNAs made from stable isotope-labeled nucleotides to advance the study of their structure and dynamics by nuclear magnetic resonance (NMR) spectroscopy. A particularly effective means of obtaining labeled nucleotides is to harvest these nucleotides from bacteria grown in defined minimal media supplemented with 15NH4Cl and various carbon sources. Given the high cost of carbon precursors required for labeling nucleic acids for NMR studies, it becomes important to evaluate the optimal growth for commonly used strains under standard minimal media conditions. Such information is lacking. In this study, we characterize the growth for Escherichia coli strains K12, K10zwf, and DL323 in three minimal media with isotopic-labeled carbon sources of acetate, glycerol, and glycerol combined with formate. Of the three media, the LeMaster-Richards and the Studier media outperform the commonly used M9 media and both support optimal growth of E. coli for the production of nucleotides. However, the growth of all three E. coli strains in acetate is reduced almost twofold compared to growth in glycerol. Analysis of the metabolic pathway and previous gene array studies help to explain this differential growth in glycerol and acetate. These studies should benefit efforts to make selective 13C-15N isotopic-labeled nucleotides for synthesizing biologically important RNAs.

Procalcitonin-Guided Antibiotic Therapy Reduces Antibiotic Use for Lower Respiratory Tract Infections in a United States Medical Center: Results of a Clinical Trial.

BACKGROUND: European trials using procalcitonin (PCT)-guided antibiotic therapy for patients with lower respiratory tract infections (LRTIs) have demonstrated significant reductions in antibiotic use without increasing adverse outcomes. Few studies have examined PCT for LRTIs in the United States. METHODS: In this study, we evaluated whether a PCT algorithm would reduce antibiotic exposure in patients with LRTI in a US hospital. We conducted a controlled pre-post trial comparing an intervention group of PCT-guided antibiotic therapy to a control group of usual care. Consecutive patients admitted to medicine services and receiving antibiotics for LRTI were enrolled in the intervention. Providers were encouraged to discontinue antibiotics according to a PCT algorithm. Control patients were similar patients admitted before the intervention. RESULTS: The primary endpoint was median antibiotic duration. Overall adverse outcomes at 30 days comprised death, transfer to an intensive care unit, antibiotic side effects, Clostridium difficile infection, disease-specific complications, and post-discharge antibiotic prescription for LRTI. One hundred seventy-four intervention patients and 200 controls were enrolled. Providers complied with the PCT algorithm in 75% of encounters. Procalcitonin-guided therapy reduced median antibiotic duration for pneumonia from 7 days to 6 (P = .045) and acute exacerbation of chronic obstructive pulmonary disease (AECOPD) from 4 days to 3 (P = .01). There was no difference in the rate of adverse outcomes in the PCT and control groups. CONCLUSIONS: A PCT-guided algorithm safely reduced the duration of antibiotics for treating LRTI. Utilization of a PCT algorithm may aid antibiotic stewardship efforts.This clinical trial was a single-center, controlled, pre-post study of PCT-guided antibiotic therapy for LRTI. The intervention (incorporation of PCT-guided algorithms) started on April 1, 2017: the preintervention (control group) comprised patients admitted from November 1, 2016 to April 16, 2017, and the postintervention group comprised patients admitted from April 17, 2017 to November 29, 2017 (Supplementary Figure 1). The study comprised patients admitted to the internal medicine services to a medical ward, the Medical Intensive Care Unit (MICU), the Cardiac Intensive Care Unit (CICU), or the Progressive Care Unit (PCU) "step down unit". The registration data for the trails are in the ClinicalTrials.gov database, number NCT0310910.