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We performed studies investigating the feasibility of human to animal (H2A) model system to test whether patient generated respiratory bioaerosols hold infective capacity when traversing long distance airborne transport within the built environment. South African patients, clinically confirmed by facemask sampling to be exhaling SARS-CoV-2 genomic sequence, were recruited and housed for multiple days in a clinical ward with a uniquely designed building ventilation system continuously channeling exhaust airflow to individual microisolator animal caging units located proximal but segregated from clinic space (University of Pretoria AIR facility).

Progressive fibrosing interstitial lung diseases (PFILDs) cause substantial morbidity and mortality. Antifibrotic agents slow progression, but most of the clinical need remains unmet. The archetypal PFILD is idiopathic pulmonary fibrosis (IPF). Chronic progression is driven by transforming growth factor (TGF-)β1 signalling. It is punctuated by inflammatory flares known as acute exacerbations (AE-IPF), which are associated with accelerated decline and high mortality. We hypothesized that acute injury responses underlying exacerbations and the mechanisms of chronic fibrosis overlap at the molecular level, via a cell surface assembly nucleated by galectin-3 that we term the ‘gal-3-fibrosome’. We focused upon a putative pro-inflammatory galectin-3 ligand, the CD98:integrin complex. Our data indicate CD98 and β1-integrin co-localise with galectin-3 within epithelial cells in IPF lung tissue, and within 40 nm in human lung tissue treated with TGF-β1 compared to controls. CD98 is required for interleukin (IL-)6 and IL-8 responses to biochemical and biophysical conditions mimicking stimuli of AE-IPF in vivo, ex vivo and in cells, and for an interstitial neutrophilic response in a mouse model. We demonstrate this pathway progresses via intracellular influx of Ca2+ mediated by TRPV4, and NF-κB activation, operating in positive feedback. Lastly we show the CD98- and galectin-3-dependence of IL-6 and IL-8 responses to the SARS-CoV-2 spike protein receptor binding domain and the conservation of this response pattern between lung epithelial cells and monocyte-derived macrophages. Taken together our findings identify CD98 as a key mediator of both pro-fibrotic and acute inflammatory responses in the lung with relevance to AE- and chronic progression of IPF, and the priming of fibrotic lungs for acute inflammatory responses. They similarly implicate CD98 and galectin-3 as mediators of COVID pneumonitis and worse outcomes in ILD patients with COVID.

IntroductionThis study aims to measure how transmission of SARS-CoV-2 occurs in communities and to identify conditions that lend to increased transmission focusing on congregate situations. We will measure SARS-CoV-2 in exhaled breath of asymptomatic and symptomatic persons using face mask sampling—a non-invasive method for SARS-CoV-2 detection in exhaled air. We aim to detect transmission clusters and identify risk factors for SARS-CoV-2 transmission in presymptomatic, asymptomatic and symptomatic individuals.Methods and analysisIn this observational prospective study with daily follow-up, index cases and their respective contacts are identified at each participating institution. Contact definitions are based on Centers for Disease Control and Prevention and local health department guidelines. Participants will wear masks with polyvinyl alcohol test strips adhered to the inside for 2 hours daily. The strips are applied to all masks used over at least 7 days. In addition, self-administered nasal swabs and (optional) finger prick blood samples are performed by participants. Samples are tested by standard PCR protocols and by novel antigen tests.Ethics and disseminationThis study was approved by the Colorado Multiple Institutional Review Board and the WHO Ethics Review Committee. From the data generated, we will analyse transmission clusters and risk factors for transmission of SARS-CoV-2 in congregate settings. The kinetics of asymptomatic transmission and the evaluation of non-invasive tools for detection of transmissibility are of crucial importance for the development of more targeted control interventions—and ultimately to assist with keeping congregate settings open that are essential for our social fabric.Trial registration numberClinicalTrials.gov (#NCT05145803).

Helicobacter pylori is a major bacterial pathogen involved in several gastrointestinal diseases. Transmission routes and reservoirs of H pylori are not well understood despite several studies. In contrast to many other infectious diseases, clinical symptoms allowing definitive diagnosis of infection are absent. Person-to-person transmission with faecal-oral and oral-oral routes have been proposed with socio-economic status and density of living as associated factors. Studies have shown that H pylori can survive in water for prolonged periods leading to a waterborne transmission route being proposed but not conclusively identified. This paper describes studies using mature heterotrophic mixed-species biofilms grown under oligotrophic conditions using a continuous-culture chemostat system. The biofilms were challenged with Helicobacter pylori (NCTC 11637). Results indicate the presence of H pylori associated with the biofilm for up to 192h post-challenge, suggesting that biofilms in water distribution systems could be a possible and as yet unrecognised reservoir of H pylori.

This book is without doubt one of the most important publications that I have read for a very long time. These stories by Iraqi scholars raise many important insights, issues and questions. Their accounts provide some chilling insights into the terrible forms of oppression and discrimination that are part of the barriers to the realisation of an inclusive and creative development. It is extremely difficult to appreciate the pain and suffering that has been an integral part of their lives. Their accounts are readable and refreshingly honest. I do believe that there is a moral responsibility for all members of departments in universities to read and discuss this book as a matter of urgency. This needs to be done in terms of what we can learn about Iraq and in turn, to critically examine our own current conditions, relations, policies and practices, so that we can also struggle for a more inclusive system of educational provision and practice in higher education.

The mechanism of the Crystal Violet (CV) reaction, a trait which has been related to biotype, source and pathogenicity in Staphylococcus aureus, was investigated in agar and broth studies. White reactions could be converted to purple and vice versa by altering the incubation conditions on agar. Broth reactions examined macroscopically and by spectrophotometry revealed that both white and purple human biotype strains take up CV but the former then progressively modify the dye more quickly than the latter. A cell-associated product of CV was detected in white and purple strains by reverse-phase thin-layer chromatography of methanol extracts. White strains appear to produce a second additional product from CV. The white reaction was not inhibited by chloramphenicol or azide but did depend on viable cells with a nutrient source. CV MICs and MBCs for 10 white and 10 purple reactors showed no gross differences in susceptibility, while a standardized assay for the rate of CV modifying activity (52 strains) demonstrated that the two categories comprise discrete populations which alter CV at different rates. Although most white strains belong to either or both of phage-typing groups V and II, purple strains with this pattern of susceptibility and white strains without it both occur. The capacity to modify CV slowly or rapidly appears to subdivide human biotype strains independently of their phage group and is associated in the former case with their capacity to produce hospital-acquired and invasive infections.

This well–organized Symposium took place on 9–10 November 1985 in an air of optimism commensurate with the recent Nobel Peace Prize announcement. Some 250 participants gathered in well‐appointed surroundings of the Free University of Brussels for a day of lectures followed by a day of workshops. Amongst an impressive array of dignitaries Kevin Craig (Medical Campaign Against Nuclear Weapons, UK) proved an adroit chairman—supervising the delivery of the Symposium with appropriate obstetric puns.

A conference on the needs of Africa in the sphere of health and nutrition, organized jointly by the Medical Association for Prevention of War and the United Nations Association of Great Britain and Northern Ireland, was held on 27 September 1986 at the Royal Society of Medicine, London. Brief accounts of the papers presented are reported here. The full proceedings have been published as a Supplement to the Journal of Tropical Pediatrics (Vol. 33, June 1987).

We have established a semi-automated microtiter-based system for the quantification of dye binding to cultured eukaryotic cells. This system has been applied to the quantitation of toxic activities that disrupt cell monolayers and their neutralization. We have used this background as a basis for developing a detection and characterization system for activities that do not cause such gross toxicity. A prototype system has been established based on three staining procedures which in broad terms assess cellular dehydrogenase activity, and protein, DNA, and RNA content. The activity of several agents affecting cyclic nucleotide metabolism, including cholera toxin, on the staining properties of exposed monolayers has been assessed. Several new categories of cellular response are readily discernible in this latter system indicating that biological activities may be identified on the basis of the pattern of such responses. Since microtiter based systems show considerable potential for automation, it is suggested that the further development of this approach could offer a realistic prospect for numerous forms of toxicity testing on an industrial scale.

An infant with severe combined immunodeficiency (SCID) is described, who presented with severe anaemia and hepatosplenomegaly due to disseminated Bacillus Calmette-Guérin (BCG) infection involving the bone marrow, liver and spleen. After BMT, huge splenic enlargement occurred, presumably due to proliferation of engrafted donor lymphocytes, leading to severe hypersplenism. Peripheral blood cell consumption was resolved by splenectomy, but gradual loss of the marrow graft followed.

A new instrument designed to enhance use of the Gigli saw is particularly valuable in performing pelvic and long-bone osteotomies. This instrument has a dual function in aiding the passage of the Gigli saw and as a periosteal elevator. Design, implementation, and procedures are outlined with illustrations.