Low-dose hydrocortisone in patients with COVID-19 and severe hypoxia (COVID STEROID) trial—Protocol and statistical analysis plan

Introduction

Severe acute respiratory syndrome coronavirus-2 has caused a pandemic of coronavirus disease (COVID-19) with many patients developing hypoxic respiratory failure. Corticosteroids reduce the time on mechanical ventilation, length of stay in the intensive care unit and potentially also mortality in similar patient populations. However, corticosteroids have undesirable effects, including longer time to viral clearance. Clinical equipoise on the use of corticosteroids for COVID-19 exists.

Methods

The COVID STEROID trial is an international, randomised, stratified, blinded clinical trial. We will allocate 1000 adult patients with COVID-19 receiving ≥10 L/min of oxygen or on mechanical ventilation to intravenous hydrocortisone 200 mg daily vs placebo (0.9% saline) for 7 days. The primary outcome is days alive without life support (ie mechanical ventilation, circulatory support, and renal replacement therapy) at day 28. Secondary outcomes are serious adverse reactions at day 14; days alive without life support at day 90; days alive and out of hospital at day 90; all-cause mortality at day 28, day 90, and 1 year; and health-related quality of life at 1 year. We will conduct the statistical analyses according to this protocol, including interim analyses for every 250 patients followed for 28 days. The primary outcome will be compared using the Kryger Jensen and Lange test in the intention to treat population and reported as differences in means and medians with 95% confidence intervals.

Discussion

The COVID STEROID trial will provide important evidence to guide the use of corticosteroids in COVID-19 and severe hypoxia.

     

Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia

The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.     

Toxicity of legume seeds to rhizobia: Selective marker for strain identification and selection of toxin-free seeds

Seeds of legume species Argyrolobium flaccidum, Desmodium elegans, D. tortuosum, Indigofera gangetica, Lespedeza stenocarpa and Sesbania sesban have been evaluated for the toxicity to rhizobia for the first time. Legume species differ in quantity and quality of released seed toxins to which the symbiotic bacteria respond differentially. Therefore, seed toxicity may be used as a selectable taxonomic marker for the strainal identification of rhizobia. Seed toxins are located in seed coat and are thermolabile to some extent. The seed genotypes, within the species, differ in toxicity and such polymorphism can be used in the selection of toxin-free seeds. Seed surface-disinfection procedures involving subsequent soaking and washing with water are the most useful methods for reducing the seed toxins. The seed toxins from I. gangetica inhibited the growth of its homologous strain but did not affect nodulation and symbiotic parameters. Various seed-toxin-producing legume species did not affect nodulation and symbiotic efficiency and effectiveness.     

The use of a double-marker shuttle vector to study DNA double-strand break repair in wild-type and radiation-sensitive mutants of the yeast Saccharomyces cerevisiae

An episomal DNA vector (YpJA18), encoding two selectable recombinant yeast genes (TRP1, URA3), was constructed to assess the fidelity of DNA repair in haploid repair-competent (RAD) wild-type yeast and several radiation-sensitive mutants. Either a DNA double-strand break (DSB) or a double-strand gap of 169 bp (DSG) was introduced by restriction enzymes in-vitro within the coding sequence of the URA3 gene of this vector. To eliminate transfer artefacts, selection was first applied for the undamaged TRP1 gene followed by counter selection for URA3 gene activity, which indicated correct repair of the DSB and DSG. Correct repair of the damaged URA3 gene was found to be about 90% in RAD cells (normalized for the expression of undamaged URA3 in TRP ⁺ transformants). Plasmids isolated from the transformants (URA ⁺ TRP ⁺) carry both unique sites (ApaI and NcoI) within the URA3 gene indicating the precise restitution of the 169-bp gap. An excision-repair-defective rad4-4 mutant repaired these lesions as correctly as RAD cells, whereas the mutants rad50-1, rad51-1 and rad54-1, proven to be defective in DSB repair and mitotic recombination, showed less than 5% correct repair of such lesions. In contrast, a representative of the RAD6 epistasis group of genes, the rev2-1 mutant which is sensitive towards UV and ionizing radiation, had a significantly reduced ability (about 20%) for the correct repair of both DSBs and DSGs.