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SARS-CoV-2 is a newly emerged coronavirus, causing the global pandemic of respiratory coronavirus disease (COVID-19). The type I interferon (IFN) pathway is of particular importance for anti-viral defense and recent studies identified that type I IFNs drive early inflammatory responses to SARS-CoV-2. Here, we use a mouse model of SARS-CoV-2 infection, facilitating viral entry by intranasal recombinant Adeno-Associated Virus (rAAV) transduction of hACE2 in wildtype (WT) and type I IFN receptor-1 deficient (Ifnar1–/–) mice, to study the role of type I IFN signalling and innate immune responses during SARS-CoV-2 infection. Our data show that type I IFN signalling is essential for inducing anti-viral effector responses to SARS-CoV-2, control of virus replication, and to prevent enhanced disease. Furthermore, hACE2-Ifnar1–/– mice had increased gene expression of the chemokine Cxcl1 and airway infiltration of neutrophils as well as reduced and delayed production of monocyte-recruiting chemokine CCL2. hACE2-Ifnar1–/– mice showed altered recruitment of inflammatory myeloid cells to the lung upon SARS-CoV-2 infection, with a shift from Ly6C+ to Ly6C– expressing cells. Together, our findings suggest that type I IFN signalling deficiency results in a dysregulated innate immune response to SARS-CoV-2 infection.

Background We explore severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody lateral flow immunoassay (LFIA) performance under field conditions compared to laboratory-based electrochemiluminescence immunoassay (ECLIA) and live virus neutralization. Methods In July 2021, 3758 participants performed, at home, a self-administered Fortress LFIA on finger-prick blood, reported and submitted a photograph of the result, and provided a self-collected capillary blood sample for assessment of immunoglobulin G (IgG) antibodies using the Roche Elecsys® Anti-SARS-CoV-2 ECLIA. We compared the self-reported LFIA result to the quantitative ECLIA and checked the reading of the LFIA result with an automated image analysis (ALFA). In a subsample of 250 participants, we compared the results to live virus neutralization. Results Almost all participants (3593/3758, 95.6%) had been vaccinated or reported prior infection. Overall, 2777/3758 (73.9%) were positive on self-reported LFIA, 2811/3457 (81.3%) positive by LFIA when ALFA-reported, and 3622/3758 (96.4%) positive on ECLIA (using the manufacturer reference standard threshold for positivity of 0.8 U mL–1). Live virus neutralization was detected in 169 of 250 randomly selected samples (67.6%); 133/169 were positive with self-reported LFIA (sensitivity 78.7%; 95% confidence interval [CI]: 71.8, 84.6), 142/155 (91.6%; 95% CI: 86.1, 95.5) with ALFA, and 169 (100%; 95% CI: 97.8, 100.0) with ECLIA. There were 81 samples with no detectable virus neutralization; 47/81 were negative with self-reported LFIA (specificity 58.0%; 95% CI: 46.5, 68.9), 34/75 (45.3%; 95% CI: 33.8, 57.3) with ALFA, and 0/81 (0%; 95% CI: 0, 4.5) with ECLIA. Conclusions Self-administered LFIA is less sensitive than a quantitative antibody test, but the positivity in LFIA correlates better than the quantitative ECLIA with virus neutralization.

Background: High trait self-control is associated with greater tolerance of unpleasant sensations including effort and pain. Dyspnoea and pain have several commonalities and this study aimed to investigate for the first time whether trait self-control influences responses to a hypercapnic rebreathing challenge designed to induce dyspnoea. As sex also influences tolerance to dyspnoea, we also sought to investigate whether this moderated the role of trait self-control.\ud \ud Methods: Participants (n = 65, 32 females) scoring high or low for trait self-control, performed a standardised rebreathing challenge, in which inspired carbon dioxide (CO2) gradually increased over a period of 6 min or until an intolerable level of dyspnoea. Air hunger (AH) intensity – a distinctive quality of dyspnoea, was measured every 30 s. The multidimensional dyspnoea profile (MDP) was completed after the rebreathing challenge for a more complete overview of breathing discomfort.\ud \ud Results: Males high in trait self-control (SCHIGH) (302 ± 42 s), tolerated the rebreathing challenge for longer than males low in self-control (SCLOW) (252 ± 66 s, P = 0.021), experienced slower increases in AH intensity during the rebreathing challenge (0.03 ± 0.01 cm.s − 1 vs. 0.04 ± 0.01 cm.s − 1, P = 0.045) and reported lower perceived mental effort on the MDP (4.94 ± 2.46 vs. 7.06 ± 1.60, P = 0.007). There was no difference between SCHIGH and SCLOW females for challenge duration. However, SCHIGH females (9.29 ± 0.66 cm) reported greater air hunger at the end of the challenge than SCLOW females (7.75 ± 1.75 cm, P = 0.003). It is possible that SCLOW females were unwilling to tolerate the same perceptual intensity of AH as the SCHIGH females.\ud \ud Conclusions: These results indicate that individuals high in trait self-control are more tolerant of dyspnoea during a CO2 rebreathing challenge than low self-control individuals. Tolerance of the stimulus was moderated by the sex of the participant, presenting an interesting opportunity for future research.

Mature tRNAs are generated by multiple RNA processing events, which can include the excision of intervening sequences. The tRNA splicing endonuclease (TSEN) complex is responsible for cleaving these intron-containing pre-tRNA transcripts. In humans, TSEN copurifies with CLP1, an RNA kinase. Despite extensive work on CLP1, its in vivo connection to tRNA splicing remains unclear. Interestingly, mutations in CLP1 or TSEN genes cause neurological diseases in humans that are collectively termed Pontocerebellar Hypoplasia (PCH). In mice, loss of Clp1 kinase activity results in premature death, microcephaly and progressive loss of motor function. To determine if similar phenotypes are observed in Drosophila, we characterized mutations in crowded-by-cid (cbc), the CLP1 ortholog, as well as in the fly ortholog of human TSEN54. Analyses of organismal viability, larval locomotion and brain size revealed that mutations in both cbc and Tsen54 phenocopy those in mammals in several details. In addition to an overall reduction in brain lobe size, we also found increased cell death in mutant larval brains. Ubiquitous or tissue-specific knockdown of cbc in neurons and muscles reduced viability and locomotor function. These findings indicate that we can successfully model PCH in a genetically-tractable invertebrate.

The coronavirus disease 2019 (COVID-19) pandemic has taken an unprecedented global toll and vaccination is needed to restore healthy living. Timely inclusion of children in vaccination trials is critical. We surveyed caregivers of children seeking care in 17 Emergency Departments (ED) across 6 countries during the peak of the pandemic to identify factors associated with intent to participate in COVID-19 vaccine trials. Questions about child and parent characteristics, COVID-19 expressed concerns and parental attitudes toward participation in a trial were asked.Of 2768 completed surveys, 18.4% parents stated they would enroll their child in a clinical trial for a COVID-19 vaccine and 14.4% would agree to a randomized placebo-controlled study. Factors associated with willingness to participate were parents agreeing to enroll in a COVID-19 vaccine trial themselves (Odds Ratio (OR) 32.9, 95% Confidence Interval (CI) (21.9-51.2)) having an older child (OR 1.0 (1.0-1.01)), having children who received all vaccinations based on their country schedule (OR 2.67 (1.35-5.71)) and parents with high school education or lower (OR 1.79 (1.18-2.74)). Mothers were less likely to enroll their child in a trial (OR 0.68 (0.47-0.97)). Only one fifth of families surveyed will consider enrolling their child in a vaccine trial. Parental interest in participation, history of vaccinating their child, and the child being older all are associated with parents allowing their child to participate in a COVID vaccine trial. This information may help decision-makers and researchers shape their strategies for trial design and participation engagement in upcoming COVID19 vaccination trials.

OBJECTIVE: To determine if caregivers of children presenting to pediatric emergency departments (EDs) during the COVID-19 pandemic are delaying presenting to care for fear of contracting COVID-19. METHODS: This was a pre-planned secondary analysis of a cross-sectional survey study of caregivers accompanying their children aged 0-19 years to 16 pediatric EDs in 5 countries from May to June 2020. An anonymous online survey, completed by caregivers via RedCAP, included caregiver and child demographics, presenting complaints, if they delayed presentation and whether symptoms worsened during this interval, as well as caregiver concern about the child or caregiver having COVID-19 at the time of ED visit. RESULTS: Of 1543 caregivers completing the survey, 287 (18.6%) reported a delay in seeking ED care due to concerns of contracting COVID-19 in the hospital. Of those, 124 (43.2%) stated their child's symptoms worsened during the waiting interval. Caregiver relationship to child [mother] (OR 1.85, 95% CI 1.27-2.76), presence of chronic illness in child (OR 1.78. 95% CI 1.14-2.79), younger age of caregiver (OR 0.965, 95% CI 0.943-0.986), and caregiver concerns about lost work during the pandemic (OR 1.08, 95% CI 1.04-1.12) were independently associated with a COVID-19-related delayed presentation in multivariable regression analysis. CONCLUSIONS: Almost one in five caregivers reported delaying ED presentation for their ill or injured child specifically due to fear of contracting COVID-19 while in hospital, with mothers, younger caregivers, caregivers of children with chronic illness, and those concerned about lost work more likely to report delaying ED presentation.

Background The prevalence and persistence of antibodies following a peak SARS-CoV-2 infection provides insights into its spread in the community, the likelihood of reinfection and potential for some level of population immunity.Methods Prevalence of antibody positivity in England, UK (REACT2) with three cross-sectional surveys between late June and September 2020. 365104 adults used a self-administered lateral flow immunoassay (LFIA) test for IgG. A laboratory comparison of LFIA results to neutralization activity in panel of sera was performed.Results There were 17,576 positive tests over the three rounds. Antibody prevalence, adjusted for test characteristics and weighted to the adult population of England, declined from 6.0% [5.8, 6.1], to 4.8% [4.7, 5.0] and 4.4% [4.3, 4.5], a fall of 26.5% [-29.0, −23.8] over the three months of the study. There was a decline between rounds 1 and 3 in all age groups, with the highest prevalence of a positive result and smallest overall decline in positivity in the youngest age group (18-24 years: −14.9% [-21.6, −8.1]), and lowest prevalence and largest decline in the oldest group (75+ years: −39.0% [-50.8, −27.2]); there was no change in antibody positivity between rounds 1 and 3 in healthcare workers (+3.45% [-5.7, +12.7]).The decline from rounds 1 to 3 was largest in those who did not report a history of COVID-19, (−64.0% [-75.6, −52.3]), compared to −22.3% ([-27.0, −17.7]) in those with SARS-CoV-2 infection confirmed on PCR.Discussion These findings provide evidence of variable waning in antibody positivity over time such that, at the start of the second wave of infection in England, only 4.4% of adults had detectable IgG antibodies using an LFIA. Antibody positivity was greater in those who reported a positive PCR and lower in older people and those with asymptomatic infection. These data suggest the possibility of decreasing population immunity and increasing risk of reinfection as detectable antibodies decline in the population.Competing Interest StatementThe authors have declared no competing interest.Funding StatementThis work was funded by the Department of Health and Social Care in England. We thank key collaborators on this work -- Ipsos MORI: Stephen Finlay, John Kennedy, Kevin Pickering, Duncan Peskett, Sam Clemens and Kelly Beaver; Institute of Global Health Innovation at Imperial College: Gianluca Fontana, Dr Hutan Ashrafian, Sutha Satkunarajah and Lenny Naar; Imperial College Healthcare NHS Trust: Robert Klaber; the Patient Experience Research Centre and the REACT Public Advisory Panel; NHS Digital for access to the NHS Register. HW is a NIHR Senior Investigator and acknowledges support from NIHR Biomedical Research Centre of Imperial College NHS Trust, NIHR School of Public Health Research, NIHR Applied Research Collaborative North West London, Wellcome Trust 205456/Z/16/Z. GC is supported by an NIHR Professorship. WSB is the Action Medical Research Professor, AD is an NIHR senior investigator and DA is an Emeritus NIHR Senior Investigator. SR acknowledges support from MRC Centre for Global Infectious Disease Analysis, National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU), Wellcome Trust (200861/Z/16/Z, 200187/Z/15/Z), and Centres for Disease Control and Prevention (US, U01CK0005-01-02) PE is Director of the MRC Centre for Environment and Health (MR/L01341X/1, MR/S019669/1). PE acknowledges support from the NIHR Imperial Biomedical Research Centre and the NIHR HPRUs in Environmental Exposures and Health and Chemical and Radiation Threats and Hazards, the British Heart Foundation Centre for Research Excellence at Imperial College London (RE/18/4/34215) and the UK Dementia Research Institute at Imperial (MC_PC_17114). We thank the Huo Family Foundation for support of our work on COVID-19. Author DeclarationsI confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.YesThe details of the IRB/oversight body that provided approval or exemption for the research described are given below:We obtained research ethics approval from the South Central-Berkshire B Research Ethics Committee (IRAS ID: 283787) All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesThe original datasets generated or analysed, or both, during this study are not publicly available because of governance restrictions and the identifiable nature of the data.

PURPOSE: This study determined the predictors of caregivers' willingness to accept an accelerated regulatory process for the development of vaccines against coronavirus disease 2019 (COVID-19). METHODS: An international cross-sectional survey was administered to 2557 caregivers of children in 17 pediatric emergency departments (EDs) across 6 countries from March 26, 2020, to June 30, 2020. Caregivers were asked to select 1 of 4 choices with which they most agreed regarding a proposed COVID-19 vaccine-approval process, in addition to questions regarding demographic characteristics, the ED visit, and attitudes about COVID-19. Univariate analyses were conducted using the Mann-Whitney U test for comparing non-normally distributed continuous variables, an independent t test for comparing normally distributed continuous variables, and a ?(2) or Fisher exact test for categorical variables. Multivariate logistic regression analysis was used for determining independent factors associated with caregivers' willingness to accept abridged development of a COVID-19 vaccine. A P value of

The ovarian follicle is a major site of steroidogenesis, crucially required for normal ovarian function and female reproduction. Our understanding of androgen synthesis and metabolism in the developing follicle has been limited by the sensitivity and specificity issues of previously used assays. Here we used liquid chromatography–tandem mass spectrometry to map the stage-dependent endogenous steroid metabolome in an encapsulated in vitro follicle growth system, from murine secondary through antral follicles. Furthermore, follicles were cultured in the presence of androgen precursors, nonaromatizable active androgen, and androgen receptor (AR) antagonists to assess effects on steroidogenesis and follicle development. Cultured follicles showed a stage-dependent increase in endogenous androgen, estrogen, and progesterone production, and incubations with the sex steroid precursor dehydroepiandrosterone revealed the follicle as capable of active androgen synthesis at early developmental stages. Androgen exposure and antagonism demonstrated AR–mediated effects on follicle growth and antrum formation that followed a biphasic pattern, with low levels of androgens inducing more rapid follicle maturation and high doses inhibiting oocyte maturation and follicle growth. Crucially, our study provides evidence for an intrafollicular feedback circuit regulating steroidogenesis, with decreased follicle androgen synthesis after exogenous androgen exposure and increased androgen output after additional AR antagonist treatment. We propose that this feedback circuit helps maintain an equilibrium of androgen exposure in the developing follicle. The observed biphasic response of follicle growth and function in increasing androgen supplementations has implications for our understanding of polycystic ovary syndrome pathophysiology and the dose-dependent utility of androgens in in vitro fertilization settings., Steroid metabolome analysis by mass spectrometry in the isolated ovarian follicle revealed early developmental capacity for androgen synthesis, which was upregulated by androgen receptor antagonists.

Capsids of papilloma and polyoma viruses (papovavirus family) are composed of 72 pentameric capsomeres arranged on a skewed icosahedral lattice (triangulation number of seven, T = 7). Cottontail rabbit papillomavirus (CRPV) was reported previously to be a T = 7laevo (left-handed) structure, whereas human wart virus, simian virus 40, and murine polyomavirus were shown to be T = 7dextro (right-handed). The CRPV structure determined by cryoelectron microscopy and image reconstruction was similar to previously determined structures of bovine papillomavirus type 1 (BPV-1) and human papillomavirus type 1 (HPV-1). CRPV capsids were observed in closed (compact) and open (swollen) forms. Both forms have star-shaped capsomeres, as do BPV-1 and HPV-1, but the open CRPV capsids are approximately 2 nm larger in radius. The lattice hands of all papillomaviruses examined in this study were found to be T = 7dextro. In the region of maximum contact, papillomavirus capsomeres interact in a manner similar to that found in polyomaviruses. Although papilloma and polyoma viruses have differences in capsid size (approximately 60 versus approximately 50 nm), capsomere morphology (11 to 12 nm star-shaped versus 8 nm barrel-shaped), and intercapsomere interactions (slightly different contacts between capsomeres), papovavirus capsids have a conserved, 72-pentamer, T = 7dextro structure. These features are conserved despite significant differences in amino acid sequences of the major capsid proteins. The conserved features may be a consequence of stable contacts that occur within capsomeres and flexible links that form among capsomeres.

Six patients with the physiological features of the myasthenic syndrome associated with carcinoma are presented. The clinical features encountered in this group, including age, mode of onset, and duration of symptom indicate that it may escape detection owing to its resemblance to other neuromuscular disorders. Conventional concentric needle electromyography may lead to the disorder being confused with a myopathy. The association with carcinoma is by no means constant. Clinical and physiological improvement with guanidine is described in each case.

Changes in amplitude of the evoked muscle action potential (MAP) have been observed in four patients with myotonia congenita and two with dystrophia myotonica. A fade in the response occurred in every case with stimulus frequencies of 10 per second or less, provided that the muscle was in a rested state and that long enough stimulus trains were used. Intramuscular stimulation and recording techniques show that the myotonic muscle fibre is the site of this defect. The MAP fade is thought to represent the transient weakness from which such patients may suffer, particularly after rest. Since neither this weakness nor the fade was related to the severity of the myotonia, nor were they significantly influenced by cooling or hydantoins, they may well be due to a separate defect in the myotonic muscle from that which causes the hyperexcitability of the fibre membrane.

SummaryInvestigation of the air-reoxidation of denatured, fully reduced chymotrypsinogen A resulted in a maximum recovery of 1.4% of enzymatically active chymotrypsin upon treatment with trypsin. Under the same conditions, urea-denatured chymotrypsinogen, which had not been reduced, yielded 100% recovery of enzymatic activity. Thus the biologically functional conformation of the polypeptide chain comprising chymotrypsinogen may not be that of greatest thermodynamic stability.

SummaryThe triggering of electrical thrombosis on electrodes depends on the coagulation steps prior to factor IX activation. Factor XII may be responsible for this phenomenon. The platelet may also play a role. It has been shown that platelet deposition is visible at potentials more positive than +0.3 V versus the normal hydrogen electrode. The same compounds which inhibit intravascular thrombosis will also impair electrical thrombosis.