The intercorrelations between blood levels of ferritin, sCD163, and IL-18 in COVID-19 patients and their association to prognosis.

Coronavirus disease 2019 (COVID-19) is associated with immune dysregulation, severe respiratory failure, and multiple organ dysfunction caused by a cytokine storm involving high blood levels of ferritin and IL-18. Furthermore, there is a resemblance between COVID-19 and macrophage activation syndrome (MAS) characterized by high concentrations of soluble CD163 (sCD163) receptor and IL-18. High levels of ferritin, IL-18, and sCD163 receptor are associated with "hyperferritinemic syndrome", a family of diseases that appears to include COVID-19. In this retrospective cohort study, we tested the association and intercorrelations in the serum levels of ferritin, sCD163, and IL-18 and their impact on the prognosis of COVID-19. We analyzed data of 70 hospitalized patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The levels of sCD163, ferritin, and IL-18 were measured and the correlation of these parameters with the respiratory deterioration and overall 30-day survival was assessed. Among the 70 patients, 60 survived 30 days from hospitalization. There were substantial differences between the subjects who were alive following 30 days compared to those who expired. The differences were referring to lymphocyte and leukocyte count, CRP, D-dimer, ferritin, sCD163, and IL-18. Results showed high levels of IL-18 (median, 444 pg/mL in the survival group compared with 916 pg/mL in the mortality group, p-value 8.54 × 10-2), a statistically significant rise in levels of ferritin (median, 484 ng/mL in the survival group compared with 1004 ng/mL in the mortality group p-value, 7.94 × 10-3), and an elevated value of in sCD163 (mean, 559 ng/mL in the survival group compared with 840 ng/mL in the mortality group, p-value 1.68 × 10-2). There was no significant correlation between the rise of ferritin and the levels sCD163 or IL-18. Taken together, sCD163, ferritin, and IL-18 were found to correlate with the severity of COVID-19 infection. Although these markers are associated with COVID-19 and might contribute to the cytokine storm, no intercorrelation was found among them. It cannot be excluded though that the results depend on the timing of sampling, assuming that they play distinct roles in different stages of the disease course. The data represented herein may provide clinical benefit in improving our understanding of the pathological course of the disease. Furthermore, measuring these biomarkers during the disease progression may help target them at the right time and refine the decision-making regarding the requirement for hospitalization.

Higher-order genomic organization of cellular functions in yeast.

Previous studies have shown that the distribution of genes in prokaryotes and eukaryotic genomes is not random. Using the thousands of cellular functions that appear in the Gene Ontology (GO) project, we exhaustively studied the relation between functionality and genomic localization of genes across 16 organisms with rich GO ontologies (one prokaryote and 15 eukaryotes). Overall, we found that the genomic distribution of cellular functions tends to be more similar in organisms that have higher evolutionary proximity. At the primary level, which measures localization of functionally related genes, the prokaryote Escherichia coli exhibits the highest level of organization, as one would expect given its operon-based genomic organization. However, examining a higher level of genomic organization by analyzing the co-localization of pairs of different functional gene groups, we surprisingly find that the eukaryote yeast Saccharomyces cerevisiae is markedly more organized than E. coli. A network-based analysis further supports this notion and suggests that the eukaryotic genomic architecture is more organized than previously thought. See online Supplementary Material at (www.liebertonline.com).

Absolute bioavailability and pharmacokinetics of linezolid in hospitalized patients given enteral feedings.

Linezolid is a new antimicrobial agent effective against drug-resistant gram-positive pathogens which are common causes of infections in hospitalized patients. Many such patients rely on the intravenous or enteral route for nutrition and drug administration. Therefore, the bioavailability of linezolid administered enterally in the presence of enteral feedings in hospitalized patients was examined. Eighteen subjects were assessed in a randomized single-dose crossover study; 12 received continuous enteral feedings, while 6 did not (controls). Both groups received linezolid 600 mg intravenously and orally (control) or enterally, with the alternate route of administration separated by a 24-h washout period. Pharmacokinetic parameters derived from noncompartmental and compartmental analysis incorporating linear and nonlinear elimination pathways were compared between groups: F, Ka, Vs, K23, K32, Vmax, Km, and K20 (bioavailability, absorption rate constant, volume of central compartment normalized to body weight, intercompartmental rate constants, maximum velocity, Michaelis-Menten constant, and elimination rate constant, respectively). Pharmacokinetic (PK) data were available from 17 patients. The linezolid oral suspension was rapidly and completely absorbed by either the oral or enteral route of administration. Bioavailability was unaltered in the presence of enteral feedings. PK estimates remain similar regardless of the model applied. At the therapeutic dose used, only slight nonlinearity in elimination was observed. A linezolid oral suspension may be administered via the enteral route to hospitalized patients without compromise in its excellent bioavailability and rapid rate of absorption. Compartmental pharmacokinetic analysis offers a more flexible study application, since bioavailability (F) can be estimated directly with intermixed intravenous/oral doses without a need for a washout period.