Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

Background: We previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15–20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in ~ 80% of cases. Methods: We report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded. Results: No gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5–528.7, P = 1.1 × 10−4) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR = 3.70[95%CI 1.3–8.2], P = 2.1 × 10−4). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR = 19.65[95%CI 2.1–2635.4], P = 3.4 × 10−3), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR = 4.40[9%CI 2.3–8.4], P = 7.7 × 10−8). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD] = 43.3 [20.3] years) than the other patients (56.0 [17.3] years; P = 1.68 × 10−5). Conclusions: Rare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old

A trial of nurse practitioner scope of practice

Aims. The aim of this paper is to report a trial to investigate the feasibility of the nurse practitioner role in local health service delivery and to provide information about the educational and legislative requirements for nurse practitioner practice. Background. Nurse practitioners have been shown to offer a beneficial service and fill a gap in health care provision. However, the lack of publications describing, critiquing, or defending the way that existing nurse practitioner roles have been developed may lead to a lack of clarity in comparing the nurse practitioner scope of practice internationally. In Australia, credible exploratory research is needed to realize the potential of nurse practitioners to bridge the divide of inequitable distribution of health services. A trial of nurse practitioner services in the Australian Capital Territory provided an excellent opportunity to investigate these scope and continuity issues. Methods. This was an observational analytic study using multiple data sources. Four models of nurse practitioner service were chosen from a competitive field of applications that were evaluated according to efficacy, feasibility, and sustainability across specified selection criteria. Each model in the trial included a clinical support team, with the nurse practitioner candidate 'working-into-the-role' and collecting demographic, clinical practice, patient outcome, and health service and consumer survey data over a 10 month period. Findings. The trial identified the broad potential of the nurse practitioner role, its breadth and limitations, and its impact on selected health services in the Australian Capital Territory. Data from individual models were compared highlighting generic elements, and formed the basis for the development of the scope of practice for the Australian Capital Territory nurse practitioner models. Conclusions. This study has validated a research-based, iterative process for initial development of nurse practitioner scope of practice for any Australian specialization. Importantly, the study concluded with the scope of practice as a finding, rather than commencing with it a priori. Although general areas of health care need and under-servicing were identified at the outset, the process tested both the expansion and parameters of the roles. What is already known about this topic: • Nurse practitioners offer a beneficial service and fill a gap in health care provision. • The nurse practitioner scope of practice varies from country to country. • Australian nurse practitioners are well positioned to bridge the divide of inequitable distribution of health services not only between metropolitan and rural/remote areas, but also within metropolitan areas. What this paper adds: • Research-based, iterative processes for development of clinical protocols that define the scope of practice for diverse nurse practitioner models. • A test of both the expansion and parameters of the roles applicable for any Australian specialization. • Systems and processes to inform health policy deliberations

Alteration of active transport after bacteriophage T5 infection

Bacteriophage T5 absorption immediately followed by injection of the first-step-transfer DNA segment produces alterations in the bacterial membrane which reduce the uptake of amino acids and of o-nitrophenyl-beta-D-galactopyranoside. Concomitantly, intracellular ATP is hydrolyzed. The extent of inhibition of uptake and of ATP hydrolysis is cooperatively increased with the multiplicity of infection. Inhibition of active transport at a high multiplicity of infection (greater than 3) is also observed after the second step of DNA injection. In contrast, at low multiplicities of infection, phage proteins are able to enhance amino acid uptake. Infection of su- bacteria with amber mutants in the first-step-transfer DNA suggests that protein A1 is implicated in this enhancement.</jats:p

In vitro synthesis of large peptide molecules using glucosylated single-stranded bacteriophage T4D DNA template.

Denatured Bacteriophage T4D DNA is able to stimulate aminoacid incorporation into TCA-precipitable material in an in vitro protein synthesis system according to base DNA sequences. Newly synthesized polypeptides remain associated with ribosomes and have a molecular weight in range of 15,000 to 45,000 Daltons

Evidence for heterogeneity in populations of T5 bacteriophage. II. Some particles are unable to inject their second-step-transfer DNA

A new class of bacteriophage was characterized in purified T5 stocks. Regardless of the host cell, these phages were irreversibly blocked at the first-step-transfer stage under conditions in which whole DNA injection normally takes place. However, they expressed their first-step-transfer functions. These observations confirmed the previously established heterogeneity of T5 bacteriophage populations and provided a new way to define a phage function necessary to release the blocking of T5 DNA injection at the first-step-transfer stage.</jats:p