Discovery of active mouse, plant and fungal cytochrome P450s in endogenous proteomes and upon expression in planta.

Eukaryotes produce a large number of cytochrome P450s that mediate the synthesis and degradation of diverse endogenous and exogenous metabolites. Yet, most of these P450s are uncharacterized and global tools to study these challenging, membrane-resident enzymes remain to be exploited. Here, we applied activity profiling of plant, mouse and fungal P450s with chemical probes that become reactive when oxidized by P450 enzymes. Identification by mass spectrometry revealed labeling of a wide range of active P450s, including six plant P450s, 40 mouse P450s and 13 P450s of the fungal wheat pathogen Zymoseptoria tritici. We next used transient expression of GFP-tagged P450s by agroinfiltration to show ER-targeting and NADPH-dependent, activity-based labeling of plant, mouse and fungal P450s. Both global profiling and transient expression can be used to detect a broad range of active P450s to study e.g. their regulation and discover selective inhibitors.

Chagas cardiomyopathy in Boston, Massachusetts: Identifying disease and improving management after community and hospital-based screening.

BACKGROUND: Limited data exist regarding cardiac manifestations of Chagas disease in migrants living in non-endemic regions. METHODS: A retrospective cohort analysis of 109 patients with Chagas disease seen at Boston Medical Center (BMC) between January 2016 and January 2023 was performed. Patients were identified by screening and testing migrants from endemic regions at a community health center and BMC. Demographic, laboratory, and cardiac evaluation data were collected. RESULTS: Mean age of the 109 patients was 43 years (range 19-76); 61% were female. 79% (86/109) were diagnosed with Chagas disease via screening and 21% (23/109) were tested given symptoms or electrocardiogram abnormalities. Common symptoms included palpitations (25%, 27/109) and chest pain (17%, 18/109); 52% (57/109) were asymptomatic. Right bundle branch block (19%, 19/102), T-wave changes (18%, 18/102), and left anterior fascicular block (11%, 11/102) were the most common electrocardiogram abnormalities; 51% (52/102) had normal electrocardiograms. Cardiomyopathy stage was ascertained in 94 of 109 patients: 51% (48/94) were indeterminate stage A and 49% (46/94) had cardiac structural disease (stages B1-D). Clinical findings that required clinical intervention or change in management were found in 23% (25/109), and included cardiomyopathy, apical hypokinesis/aneurysm, stroke, atrial or ventricular arrhythmias, and apical thrombus. CONCLUSIONS: These data show high rates of cardiac complications in a cohort of migrants living with Chagas disease in a non-endemic setting. We demonstrate that Chagas disease diagnosis prompts cardiac evaluation which often identifies actionable cardiac disease and provides opportunities for prevention and treatment.

Potential Policy and Community Implications of Equitable Organic Waste, Compost, and Urban Agricultural Systems in the United States.

BACKGROUND: Urban organic waste diverted from landfills for use as compost feedstock may help mitigate and adapt to the effects of our changing climate. Yet, compost produced from urban food and yard waste is often a source of contaminants harmful to human and environmental health. Efforts by multiple municipalities are increasing residential and commercial food and yard waste collection; however, finished, tested compost is typically unavailable to those contributing the waste and whose gardens would benefit. OBJECTIVES: This commentary evaluates the relative equity and safety of U.S. organic waste cycles in relation to urban and peri-urban agriculture (UA) and waste stewardship. We a) explore historical structures that have led to siloed food and waste systems and b) provide recommendations to promote safer compost production from urban organic waste inputs. The engagement of intersectional partners in the creation of equitable policies and contracts that integrate food and waste justice is crucial to this work. METHODS: A 15-y relationship between community, academic, and government partners in Boston, Massachusetts, has increased access to health-promoting community gardens. Historical concerns raised by gardeners resulted in improvement to the quality of compost sourced from municipal organic waste and motivated a case study of Boston and three other cities (Seattle, Washington; San Francisco, California; New York, New York). This case study provides the approaches used to source, collect, process, test, and deliver urban organic waste as compost for UA. It informed recommendations to improve the safety and equity of organic waste-to-compost cycles. DISCUSSION: Strict feedstock regulation and required compost safety testing are essential to produce safe, city-sourced compost. Balancing the needs of landfill diversion with equitable distribution to all contributors, particularly low-income and food-insecure people, will help concentrate UA benefits within marginalized communities. Adoption of a public health lens may help ensure the safety of nutrient-rich compost available for urban growers through legislation at state and local levels, along with explicit industry contracts. https://doi.org/10.1289/EHP12921.

Laboratory study of the effectiveness of substituting traditional wheat flour with low dust flour and use of different sieve designs as controls to reduce exposure to inhalable flour dust in commercial bakeries.

Exposure to flour dust remains one of the leading causes of occupational asthma in Great Britain (GB). The average annual incidence rate per 100,000 bakers and flour confectioners in GB was 47.8 for the 3 yr period 2017 to 2019 compared with 0.53 for all occupations. There are many processes in commercial bakeries that can cause exposure to flour dust. Exposures are typically controlled by using local exhaust ventilation or respiratory protective equipment. The aim of this study was to evaluate the potential to reduce exposure to inhalable flour dust in commercial bakeries by modification of the process by use of a conical sieve in place of a round sieve; and substitution of traditional wheat flour (TWF) with 'low dust' flours LD1 and LD2 for dusting surfaces. Two simulated commercial bakery tasks were performed in a laboratory whilst dust exposures were measured in the breathing zone of the operator using an Institute of Occupational Medicine (IOM) sampler, button sampler and a real-time direct reading monitor. Analysis of variance tests were used to assess whether differences in mean exposures were statistically significant with the different control approaches. A qualitative visual exposure assessment was also undertaken using Tyndall illumination. Substituting TWF with LD1 and LD2 reduced exposure to inhalable flour dust by 86% and 53% respectively when sieving and by 78% and 67% respectively when filling a hopper. There was no statistically significant difference between dust emissions for all 3 flours when using the conical sieve instead of the round sieve for flour dusting tasks. This laboratory study has shown that substituting TWF with low-dust flour may reduce inhalable dust exposures when dusting surfaces in bakeries.

Linked CD4+/CD8+ T cell neoantigen vaccination overcomes immune checkpoint blockade resistance and enables tumor regression.

Therapeutic benefit to immune checkpoint blockade (ICB) is currently limited to the subset of cancers thought to possess a sufficient tumor mutational burden (TMB) to allow for the spontaneous recognition of neoantigens (NeoAg) by autologous T cells. We explored whether the response to ICB of an aggressive low-TMB squamous cell tumor could be improved through combination immunotherapy using functionally defined NeoAg as targets for endogenous CD4+ and CD8+ T cells. We found that, whereas vaccination with CD4+ or CD8+ NeoAg alone did not offer prophylactic or therapeutic immunity, vaccines containing NeoAg recognized by both subsets overcame ICB resistance and led to the eradication of large established tumors that contained a subset of PD-L1+ tumor-initiating cancer stem cells (tCSC), provided the relevant epitopes were physically linked. Therapeutic CD4+/CD8+ T cell NeoAg vaccination produced a modified tumor microenvironment (TME) with increased numbers of NeoAg-specific CD8+ T cells existing in progenitor and intermediate exhausted states enabled by combination ICB-mediated intermolecular epitope spreading. We believe that the concepts explored herein should be exploited for the development of more potent personalized cancer vaccines that can expand the range of tumors treatable with ICB.

Antibiotics for lower respiratory tract infection in children presenting in primary care: ARTIC-PC RCT.

Background: Antimicrobial resistance is a global health threat. Antibiotics are commonly prescribed for children with uncomplicated lower respiratory tract infections, but there is little randomised evidence to support the effectiveness of antibiotics in treating these infections, either overall or relating to key clinical subgroups in which antibiotic prescribing is common (chest signs; fever; physician rating of unwell; sputum/rattly chest; shortness of breath). Objectives: To estimate the clinical effectiveness and cost-effectiveness of amoxicillin for uncomplicated lower respiratory tract infections in children both overall and in clinical subgroups. Design: Placebo-controlled trial with qualitative, observational and cost-effectiveness studies. Setting: UK general practices. Participants: Children aged 1-12 years with acute uncomplicated lower respiratory tract infections. Outcomes: The primary outcome was the duration in days of symptoms rated moderately bad or worse (measured using a validated diary). Secondary outcomes were symptom severity on days 2-4 (0 = no problem to 6 = as bad as it could be); symptom duration until very little/no problem; reconsultations for new or worsening symptoms; complications; side effects; and resource use. Methods: Children were randomised to receive 50 mg/kg/day of oral amoxicillin in divided doses for 7 days, or placebo using pre-prepared packs, using computer-generated random numbers by an independent statistician. Children who were not randomised could participate in a parallel observational study. Semistructured telephone interviews explored the views of 16 parents and 14 clinicians, and the data were analysed using thematic analysis. Throat swabs were analysed using multiplex polymerase chain reaction. Results: A total of 432 children were randomised (antibiotics, n = 221; placebo, n = 211). The primary analysis imputed missing data for 115 children. The duration of moderately bad symptoms was similar in the antibiotic and placebo groups overall (median of 5 and 6 days, respectively; hazard ratio 1.13, 95% confidence interval 0.90 to 1.42), with similar results for subgroups, and when including antibiotic prescription data from the 326 children in the observational study. Reconsultations for new or worsening symptoms (29.7% and 38.2%, respectively; risk ratio 0.80, 95% confidence interval 0.58 to 1.05), illness progression requiring hospital assessment or admission (2.4% vs. 2.0%) and side effects (38% vs. 34%) were similar in the two groups. Complete-case (n = 317) and per-protocol (n = 185) analyses were similar, and the presence of bacteria did not mediate antibiotic effectiveness. NHS costs per child were slightly higher (antibiotics, £29; placebo, £26), with no difference in non-NHS costs (antibiotics, £33; placebo, £33). A model predicting complications (with seven variables: baseline severity, difference in respiratory rate from normal for age, duration of prior illness, oxygen saturation, sputum/rattly chest, passing urine less often, and diarrhoea) had good discrimination (bootstrapped area under the receiver operator curve 0.83) and calibration. Parents found it difficult to interpret symptoms and signs, used the sounds of the child's cough to judge the severity of illness, and commonly consulted to receive a clinical examination and reassurance. Parents acknowledged that antibiotics should be used only when 'necessary', and clinicians noted a reduction in parents' expectations for antibiotics. Limitations: The study was underpowered to detect small benefits in key subgroups. Conclusion: Amoxicillin for uncomplicated lower respiratory tract infections in children is unlikely to be clinically effective or to reduce health or societal costs. Parents need better access to information, as well as clear communication about the self-management of their child's illness and safety-netting. Future work: The data can be incorporated in the Cochrane review and individual patient data meta-analysis. Trial registration: This trial is registered as ISRCTN79914298. Funding: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 27, No. 9. See the NIHR Journals Library website for further project information.

Children are commonly prescribed antibiotics for chest infections, but such infections are becoming resistant to antibiotics, and it is not clear if antibiotics work in treating them. A total of 432 children who saw their general practitioner with a chest infection were given either an antibiotic (amoxicillin) or a placebo (no antibiotic) for 7 days. Symptom diaries documented the infection's duration and its side effects. Children not in the placebo study were able to participate in another study that documented the same outcomes (an 'observational study'). We interviewed parents, doctors and nurses about their observations and concerns. Our patient and public involvement and engagement work with parents indicated that a 3-day symptom reduction was required to justify giving antibiotics. After seeing the doctor, parents whose children received antibiotics rated infective symptoms as moderately bad or worse for 5 days, and parents whose children received the placebo rated these for 6 days. Side effects and complications were similar in the two groups. Findings were similar when including the results of the observational study, and for children in whose chest the doctor could hear wheeze or rattles; who had fever; who were rated by the doctor as more unwell, who were short of breath, or who had had bacteria detected in the throat. The costs to the NHS per child were similar (antibiotics, £29; placebo, £26), and the wider costs to society were the same (antibiotics, £33; placebo, £33). Parents found it difficult to interpret their child's symptoms, and commonly used the sound of the cough to judge severity. Parents commonly consulted to receive an examination and reassurance, and accepted that antibiotics should be used only when 'necessary'. Clinicians noted a reduction in parents' expectations for antibiotics. Amoxicillin for chest infections in children is unlikely to be effective. General practitioners should support parents to self-manage at home and give clear communication about when and how to seek medical help if they continue to be concerned.

Determining the clinical and cost-effectiveness of nasal sprays and a physical activity and stress management intervention to reduce respiratory tract infections in primary care: A protocol for the 'Immune Defence' randomised controlled trial.

BACKGROUND: Most adults in the UK experience at least one viral respiratory tract infection (RTI) per year. Individuals with comorbidities and those with recurrent RTIs are at higher risk of infections. This can lead to more severe illness, worse quality of life and more days off work. There is promising evidence that using common nasal sprays or improving immune function through increasing physical activity and managing stress, may reduce the incidence and severity of RTIs. METHODS AND DESIGN: Immune Defence is an open, parallel group, randomised controlled trial. Up to 15000 adults from UK general practices, with a comorbidity or risk factor for infection and/or recurrent infections (3 or more infections per year) will be randomly allocated to i) a gel-based nasal spray designed to inhibit viral respiratory infections; ii) a saline nasal spray, iii) a digital intervention promoting physical activity and stress management, or iv) usual care with brief advice for managing infections, for 12 months. Participants will complete monthly questionnaires online. The primary outcome is the total number of days of illness due to RTIs over 6 months. Key secondary outcomes include: days with symptoms moderately bad or worse; days where work/normal activities were impaired; incidence of RTI; incidence of COVID-19; health service contacts; antibiotic usage; beliefs about antibiotics; intention to consult; number of days of illness in total due to respiratory tract infections over 12 months. Economic evaluation from an NHS perspective will compare the interventions, expressed as incremental cost effectiveness ratios. A nested mixed methods process evaluation will examine uptake and engagement with the interventions and trial procedures. TRIAL STATUS: Recruitment commenced in December 2020 and the last participant is expected to complete the trial in April 2024. DISCUSSION: Common nasal sprays and digital interventions to promote physical activity and stress management are low cost, accessible interventions applicable to primary care. If effective, they have the potential to reduce the individual and societal impact of RTIs. TRIAL REGISTRATION: Prospectively registered with ISRCTN registry (17936080) on 30/10/2020. SPONSOR: This RCT is sponsored by University of Southampton. The sponsors had no role in the study design, decision to publish, or preparation of the manuscript.

PFAS levels in paired drinking water and serum samples collected from an exposed community in Central North Carolina.

The community of Pittsboro, North Carolina has been documented to have extensive per- and polyfluoroalkyl substances (PFAS) contamination in its drinking water source, the Haw River, over the last 20 years. However, a detailed exposure assessment has never been conducted. In this study, we sought to characterize the PFAS in paired drinking water and blood samples collected from a small cohort of Pittsboro residents (n = 49). Drinking water and serum from blood were collected from adults in late 2019 and early 2020 and were analyzed to quantify 13 PFAS analytes. In order to explore potential health effects of PFAS exposure, serum was further analyzed for clinical chemistry endpoints that could be potentially associated with PFAS (e.g., cholesterol, liver function biomarkers). PFAS were detected in all serum samples, and some serum PFAS concentrations were 2 to 4 times higher than the median U.S. serum concentrations reported in the general U.S. population. Of the 13 PFAS in drinking water, perfluorohexanoic acid (PFHxA) was measured at the highest concentrations. PFAS levels in the current drinking water were not associated with current serum PFAS, suggesting that the serum PFAS in this cohort likely reflects historical exposure to PFAS with long half-lives (e.g., PFOS and PFOA). However, one PFAS with a shorter half-life (PFHxA) was observed to increase in serum, reflecting the temporal variability of PFHxA in river and drinking water. Statistical analyses indicated that serum PFOA and PFHxS were positively associated with total cholesterol and non-HDL cholesterol. No serum PFAS was associated with HDL cholesterol. In the clinical chemistry analyses, serum PFHxA was found to be negatively associated with electrolytes and liver enzymes (e.g., AST and ALT), and serum PFOS was found to be positively associated with the ratio of blood urea nitrogen to creatinine (BUN:Cre). While small in size, this study revealed extensive exposure to PFAS in Pittsboro and associations with clinical blood markers, suggesting potential health impacts in community residents.

Linked CD4 + /CD8 + T cell neoantigen vaccination overcomes immune checkpoint blockade resistance and enables tumor regression.

Therapeutic benefit to immune checkpoint blockade (ICB) is currently limited to the subset of cancers thought to possess a sufficient tumor mutational burden (TMB) to allow for the spontaneous recognition of neoantigens (NeoAg) by autologous T cells. We explored whether the response of an aggressive low TMB squamous cell tumor to ICB could be improved through combination immunotherapy using functionally defined NeoAg as targets for endogenous CD4 + and CD8 + T cells. We found that, whereas vaccination with CD4 + or CD8 + NeoAg alone did not offer prophylactic or therapeutic immunity, vaccines containing NeoAg recognized by both subsets overcame ICB resistance and led to the eradication of large established tumors that contained a subset of PD-L1 + tumor-initiating cancer stem cells (tCSC), provided the relevant epitopes were physically linked. Therapeutic CD4 + /CD8 + T cell NeoAg vaccination produced a modified tumor microenvironment (TME) with increased numbers of NeoAg-specific CD8 + T cells existing in progenitor and intermediate exhausted states enabled by combination ICB-mediated intermolecular epitope spreading. The concepts explored herein should be exploited for the development of more potent personalized cancer vaccines that can expand the range of tumors treatable with ICB.

Polluted wetlands contain multidrug-resistance plasmids encoding CTX-M-type extended-spectrum ß-lactamases.

While most detailed analyses of antibiotic resistance plasmids focus on those found in clinical isolates, less is known about the vast environmental reservoir of mobile genetic elements and the resistance and virulence factors they encode. We selectively isolated three strains of cefotaxime-resistant Escherichia coli from a wastewater-impacted coastal wetland. The cefotaxime-resistant phenotype was transmissible to a lab strain of E. coli after one hour, with frequencies as high as 10-3 transconjugants per recipient. Two of the plasmids also transferred cefotaxime resistance to Pseudomonas putida, but these were unable to back-transfer this resistance from P. putida to E. coli. In addition to the cephalosporins, E. coli transconjugants inherited resistance to at least seven distinct classes of antibiotics. Complete nucleotide sequences revealed large IncF-type plasmids with globally distributed replicon sequence types F31:A4:B1 and F18:B1:C4 carrying diverse antibiotic resistance and virulence genes. The plasmids encoded extended-spectrum ß-lactamases blaCTX-M-15 or blaCTX-M-55, each associated with the insertion sequence ISEc9, although in different local arrangements. Despite similar resistance profiles, the plasmids shared only one resistance gene in common, the aminoglycoside acetyltransferase aac(3)-IIe. Plasmid accessory cargo also included virulence factors involved in iron acquisition and defense against host immunity. Despite their sequence similarities, several large-scale recombination events were detected, including rearrangements and inversions. In conclusion, selection with a single antibiotic, cefotaxime, yielded conjugative plasmids conferring multiple resistance and virulence factors. Clearly, efforts to limit the spread of antibiotic resistance and virulence among bacteria must include a greater understanding of mobile elements in the natural and human-impacted environments.

Evaluation of Face Shields, Goggles, and Safety Glasses as a Virus Transmission Control Measure to Protect the Wearer Against Cough Droplets.

Face shields (also referred to as visors), goggles and safety glasses have been worn during the COVID-19 pandemic as one measure to control transmission of the virus. However, their effectiveness in controlling facial exposure to cough droplets is not well established and standard tests for evaluating eye protection for this application are limited. A method was developed to evaluate face shields, goggles, and safety glasses as a control measure to protect the wearer against cough droplets. The method uses a semi-quantitative assessment of facial droplet deposition. A cough simulator was developed to generate droplets comparable to those from a human cough. The droplets consisted of a UV fluorescent marker (fluorescein) in water. Fourteen face shields, four pairs of goggles and one pair of safety glasses were evaluated by mounting them on two different sizes of breathing manikin head and challenging them with the simulated cough. The manikin head was positioned in seven orientations relative to the cough simulator to represent various potential occupational exposure scenarios, for example, a nurse standing over a patient. Droplet deposition in the eyes, nose and mouth regions were visualised following three 'coughs'. Face shields, goggles, and safety glasses reduced, but did not eliminate exposure to the wearer from droplets such as those produced by a human cough. The level of protection differed based on the design of the personal protective equipment and the relative orientation of the wearer to the cough. For example, face shields, and goggles offered the greatest protection when a cough challenge was face on or from above and the least protection when a cough challenge was from below. Face shields were also evaluated as source control to protect others from the wearer. Results suggested that if a coughing person wears a face shield, it can provide some protection from cough droplets to those standing directly in front of the wearer.

Maternal exposure to perfluorobutane sulfonate (PFBS) during pregnancy: evidence of adverse maternal and fetoplacental effects in New Zealand White (NZW) rabbits.

Perfluorobutanesulfonic acid (PFBS) is a replacement for perfluorooctanesulfonic acid (PFOS) that is increasingly detected in drinking water and human serum. Higher PFBS exposure is associated with risk for preeclampsia, the leading cause of maternal and infant morbidity and mortality in the United States. This study investigated relevant maternal and fetal health outcomes after gestational exposure to PFBS in a New Zealand White rabbit model. Nulliparous female rabbits were supplied drinking water containing 0 mg/l (control), 10 mg/l (low), or 100 mg/l (high) PFBS. Maternal blood pressure, body weights, liver and kidney weights histopathology, clinical chemistry panels, and thyroid hormone levels were evaluated. Fetal endpoints evaluated at necropsy included viability, body weights, crown-rump length, and liver and kidney histopathology, whereas placenta endpoints included weight, morphology, histopathology, and full transcriptome RNA sequencing. PFBS-high dose dams exhibited significant changes in blood pressure markers, seen through increased pulse pressure and renal resistive index measures, as well as kidney histopathological changes. Fetuses from these dams showed decreased crown-rump length. Statistical analysis of placental weight via a mixed model statistical approach identified a significant interaction term between PFBS high dose and fetal sex, suggesting a sex-specific effect on placental weight. RNA sequencing identified the dysregulation of angiotensin (AGT) in PFBS high-dose placentas. These results suggest that PFBS exposure during gestation leads to adverse maternal outcomes, such as renal injury and hypertension, and fetal outcomes, including decreased growth parameters and adverse placenta function. These outcomes raise concerns about pregnant women's exposure to PFBS and pregnancy outcomes.

Simulating the Environmental Spread of SARS-CoV-2 via Cough and the Effect of Personal Mitigations.

BACKGROUND: A cough is known to transmit an aerosol cloud up to 2 m. During the COVID-19 pandemic of 2020 the United Kingdom's National Health Service (NHS), other UK government agencies and the World Health Organization (WHO) advised people to cough into their elbows. It was thought that this would reduce viral spread and protect the public. However, there is limited peer reviewed evidence to support this. OBJECTIVES: To determine if cough related interventions reduce environmental contamination, protecting members of the public from infection. METHODS: Scientists and engineers at the Health and Safety Executive (HSE) laboratory used a human cough simulator that provided a standardised cough challenge using a solution of simulated saliva and a SARS-CoV-2 surrogate virus; Phi6. Pseudomonas syringae settle plates were used to detect viable Phi6 virus following a simulated cough into a 4 × 4 m test chamber. The unimpeded pattern of contamination was compared to that when a hand or elbow was placed over the mouth during the cough. High speed back-lit video was also taken to visualise the aerosol dispersion. RESULTS AND DISCUSSION: Viable virus spread up to 2 m from the origin of the cough outwards in a cloud. Recommended interventions, such as putting a hand or elbow in front of the mouth changed the pattern of cough aerosol dispersion. A hand deflected the cough to the side, protecting those in front from exposure, however it did not prevent environmental contamination. It also allowed for viral transfer from the hand to surfaces such as door handles. A balled fist in front of the mouth did not deflect the cough. Putting an elbow in front of the mouth deflected the aerosol cloud to above and below the elbow, but would not have protected any individuals standing in front. However, if the person coughed into a sleeved elbow more of the aerosol seemed to be absorbed. Coughing into a bare elbow still allowed for transfer to the environment if people touched the inside of their elbow soon after coughing. CONCLUSIONS: Interventions can change the environmental contamination pattern resulting from a human cough but may not reduce it greatly.

A mixed methods study on effectiveness and appropriateness of face shield use as COVID-19 PPE in middle income countries.

BACKGROUND: Face shields were widely used in 2020-2021 as facial personal protective equipment (PPE). Laboratory evidence about how protective face shields might be and whether real world user priorities and usage habits conflicted with best practice for maximum possible protection was lacking - especially in limited resource settings. METHODS: Relative protective potential of 13 face shield designs were tested in a controlled laboratory setting. Community and health care workers were surveyed in middle income country cities (Brazil and Nigeria) about their preferences and perspectives on face shields as facial PPE. Priorities about facial PPE held by survey participants were compared with the implications of the laboratory-generated test results. RESULTS: No face shield tested totally eliminated exposure. Head orientation and design features influenced the level of protection. Over 600 individuals were interviewed in Brazil and Nigeria (including 240 health care workers) in March-April 2021. Respondents commented on what influenced their preferred forms of facial PPE, how they tended to clean face shields, and their priorities in choosing a face cover product. Surveyed health care workers commonly bought personal protection equipment for use at work. CONCLUSIONS: All face shields provided some protection but none gave high levels of protection against external droplet contamination. Respondents wanted facial PPE that considered good communication, secure fixture, good visibility, comfort, fashion, and has validated protectiveness.

Comparison of anterior nares CT values in asymptomatic and symptomatic individuals diagnosed with SARS-CoV-2 in a university screening program.

At our university based high throughput screening program, we test all members of our community weekly using RT-qPCR. RT-qPCR cycle threshold (CT) values are inversely proportional to the amount of viral RNA in a sample and are a proxy for viral load. We hypothesized that CT values would be higher, and thus the viral loads at the time of diagnosis would be lower, in individuals who were infected with the virus but remained asymptomatic throughout the course of the infection. We collected the N1 and N2 target gene CT values from 1633 SARS-CoV-2 positive RT-qPCR tests of individuals sampled between August 7, 2020, and March 18, 2021, at the BU Clinical Testing Laboratory. We matched this data with symptom reporting data from our clinical team. We found that asymptomatic patients had CT values significantly higher than symptomatic individuals on the day of diagnosis. Symptoms were followed by the clinical team for 10 days post the first positive test. Within the entire population, 78.1% experienced at least one symptom during surveillance by the clinical team (n = 1276/1633). Of those experiencing symptoms, the most common symptoms were nasal congestion (73%, n = 932/1276), cough (60.0%, n = 761/1276), fatigue (59.0%, n = 753/1276), and sore throat (53.1%, n = 678/1276). The least common symptoms were diarrhea (12.5%, n = 160/1276), dyspnea on exertion (DOE) (6.9%, n = 88/1276), foot or skin changes (including rash) (4.2%, n = 53/1276), and vomiting (2.1%, n = 27/1276). Presymptomatic individuals, those who were not symptomatic on the day of diagnosis but became symptomatic over the following 10 days, had CT values higher for both N1 (median = 27.1, IQR 20.2-32.9) and N2 (median = 26.6, IQR 20.1-32.8) than the symptomatic group N1 (median = 21.8, IQR 17.2-29.4) and N2 (median = 21.4, IQR 17.3-28.9) but lower than the asymptomatic group N1 (median = 29.9, IQR 23.6-35.5) and N2 (median = 30.0, IQR 23.1-35.7). This study supports the hypothesis that viral load in the anterior nares on the day of diagnosis is a measure of disease intensity at that time.

Evaluating maternal exposure to an environmental per and polyfluoroalkyl substances (PFAS) mixture during pregnancy: Adverse maternal and fetoplacental effects in a New Zealand White (NZW) rabbit model.

Mixtures of per- and polyfluoroalkyl substances (PFAS) are often found in drinking water, and serum PFAS are detected in up to 99% of the population. However, very little is known about how exposure to mixtures of PFAS affects maternal and fetal health. The aim of this study was to investigate maternal, fetal, and placental outcomes after preconceptional and gestational exposure to an environmentally relevant PFAS mixture in a New Zealand White (NZW) rabbit model. Dams were exposed via drinking water to control (no detectable PFAS) or a PFAS mixture for 32 days. This mixture was formulated with PFAS to resemble levels measured in tap water from Pittsboro, NC (10 PFAS compounds; total PFAS load = 758.6 ng/L). Maternal, fetal, and placental outcomes were evaluated at necropsy. Thyroid hormones were measured in maternal serum and kit blood. Placental gene expression was evaluated by RNAseq and qPCR. PFAS exposure resulted in higher body weight (p = 0.01), liver (p = 0.01) and kidney (p = 0.01) weights, blood pressure (p = 0.05), and BUN:CRE ratio (p = 0.04) in dams, along with microscopic changes in renal cortices. Fetal weight, measures, and histopathology were unchanged, but a significant interaction between dose and sex was detected in the fetal: placental weight ratio (p = 0.036). Placental macroscopic changes were present in PFAS-exposed dams. Dam serum showed lower T4 and a higher T3:T4 ratio, although not statistically significant. RNAseq revealed that 11 of the 14 differentially expressed genes (adj. p < 0.1) are involved in placentation or pregnancy complications. In summary, exposure elicited maternal weight gain and signs of hypertension, renal injury, sex-specific changes in placental response, and differential expression of genes involved in placentation and preeclampsia. Importantly, these are the first results to show adverse maternal and placental effects of an environmentally-relevant PFAS mixture in vivo.

Using nasal sprays to prevent respiratory tract infections: a qualitative study of online consumer reviews and primary care patient interviews.

OBJECTIVES: Nasal sprays could be a promising approach to preventing respiratory tract infections (RTIs). This study explored lay people's perceptions and experiences of using nasal sprays to prevent RTIs to identify barriers and facilitators to their adoption and continued use. DESIGN: Qualitative research. Study 1 thematically analysed online consumer reviews of an RTI prevention nasal spray. Study 2 interviewed patients about their reactions to and experiences of a digital intervention that promotes and supports nasal spray use for RTI prevention (reactively: at 'first signs' of infection and preventatively: following possible/probable exposure to infection). Interview transcripts were analysed using thematic analysis. SETTING: Primary care, UK. PARTICIPANTS: 407 online customer reviews. 13 purposively recruited primary care patients who had experienced recurrent infections and/or had risk factors for severe infections. RESULTS: Both studies identified various factors that might influence nasal spray use including: high motivation to avoid RTIs, particularly during the COVID-19 pandemic; fatalistic views about RTIs; beliefs about alternative prevention methods; the importance of personal recommendation; perceived complexity and familiarity of nasal sprays; personal experiences of spray success or failure; tolerable and off-putting side effects; concerns about medicines; and the nose as unpleasant and unhygienic. CONCLUSIONS: People who suffer disruptive, frequent or severe RTIs or who are vulnerable to RTIs are interested in using a nasal spray for prevention. They also have doubts and concerns and may encounter problems. Some of these may be reduced or eliminated by providing nasal spray users with information and advice that addresses these concerns or helps people overcome difficulties.

Concentrations of per- and polyfluoroalkyl substances (PFAS) in human placental tissues and associations with birth outcomes.

Per- and polyfluoroalkyl substances (PFAS) are ubiquitous environmental contaminants commonly detected in human serum. Previous studies have observed associations between maternal serum PFAS and adverse pregnancy and birth outcomes such as lower birth weight or pre-eclampsia; however, few studies have explored these associations with birth outcomes and placental tissue PFAS concentration. The placenta is a vital contributor to a healthy pregnancy and may be involved in the mechanism of PFAS reproductive toxicity. Our goal was to measure placental PFAS concentrations and examine associations with birth outcomes (e.g., birth weight, gestational duration). Placenta samples (n = 120) were collected during delivery from women enrolled in the Healthy Pregnancy, Healthy Baby cohort (HPHB) in Durham, North Carolina. All placenta samples contained detectable PFAS, with perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) being the most abundant and most frequently detected (all >96% detection frequency). While placental PFAS concentrations did not differ by infant sex, higher PFAS levels were observed in placenta from nulliparous women, suggesting that parity influences the accumulation of PFAS in the placenta. We used linear regression models to examine associations between placental PFAS and birth outcomes. After adjustment for parity, tobacco use, maternal age, and maternal race, we found that placental PFOS was associated with lower birth weight for gestational age in male infants and higher birth weight for gestational age in female infants. Similar findings were seen for PFNA for birth weight for gestational age. These differences in birth outcomes based on infant sex highlight a need to explore mechanistic differences in PFAS toxicity during gestation for male and female infants.

Identifying a therapeutic target for vancomycin against staphylococci in young infants.

OBJECTIVES: To determine the therapeutic target of vancomycin in young infants with staphylococcal infections. METHODS: Retrospective data were collected for infants aged 0 to 90 days with CoNS or MRSA bacteraemia over a 4 year period at the Royal Children's Hospital Melbourne, Australia. Vancomycin broth microdilution MICs were determined. A published pharmacokinetic model was externally validated using the study dataset and a time-to-event (TTE) pharmacodynamic model developed to link the AUC of vancomycin with the event being the first negative blood culture. Simulations were performed to determine the trough vancomycin concentration that correlates with a 90% PTA of the target AUC24. RESULTS: Thirty infants, 28 with CoNS and 2 with MRSA bacteraemia, who had 165 vancomycin concentrations determined were included. The vancomycin broth microdilution MIC was determined for 24 CoNS and 1 MRSA isolate, both with a median MIC of 1 mg/L (CoNS range = 0.5-4.0). An AUC0-24 target of ≥300 mg/L·h or AUC24-48 of ≥424 mg/L·h. increased the chance of bacteriological cure by 7.8- and 7.3-fold, respectively. However, AUC0-24 performed best in the pharmacokinetic-pharmacodynamic model. This correlates with 24 to 48 h trough concentrations of >15-18 mg/L and >10-15 mg/L for 6- and 12-hourly dosing, respectively, and can be used to guide vancomycin therapy in this population. CONCLUSIONS: An AUC0-24 ≥300 mg/L·h or AUC24-48 ≥424 mg/L·h was associated with an increase in bacteriological cure in young infants with staphylococcal bloodstream infections.