Arterial oxygen content is precisely maintained by graded erythrocytotic responses in settings of high/normal serum iron levels, and predicts exercise capacity: an observational study of hypoxaemic patients with pulmonary arteriovenous malformations.

Oxygen, haemoglobin and cardiac output are integrated components of oxygen transport: each gram of haemoglobin transports 1.34 mls of oxygen in the blood. Low arterial partial pressure of oxygen (PaO2), and haemoglobin saturation (SaO2), are the indices used in clinical assessments, and usually result from low inspired oxygen concentrations, or alveolar/airways disease. Our objective was to examine low blood oxygen/haemoglobin relationships in chronically compensated states without concurrent hypoxic pulmonary vasoreactivity.165 consecutive unselected patients with pulmonary arteriovenous malformations were studied, in 98 cases, pre/post embolisation treatment. 159 (96%) had hereditary haemorrhagic telangiectasia. Arterial oxygen content was calculated by SaO2 x haemoglobin x 1.34/100.There was wide variation in SaO2 on air (78.5-99, median 95)% but due to secondary erythrocytosis and resultant polycythaemia, SaO2 explained only 0.1% of the variance in arterial oxygen content per unit blood volume. Secondary erythrocytosis was achievable with low iron stores, but only if serum iron was high-normal: Low serum iron levels were associated with reduced haemoglobin per erythrocyte, and overall arterial oxygen content was lower in iron deficient patients (median 16.0 [IQR 14.9, 17.4]mls/dL compared to 18.8 [IQR 17.4, 20.1]mls/dL, p<0.0001). Exercise tolerance appeared unrelated to SaO2 but was significantly worse in patients with lower oxygen content (p<0.0001). A pre-defined athletic group had higher Hb:SaO2 and serum iron:ferritin ratios than non-athletes with normal exercise capacity. PAVM embolisation increased SaO2, but arterial oxygen content was precisely restored by a subsequent fall in haemoglobin: 86 (87.8%) patients reported no change in exercise tolerance at post-embolisation follow-up.Haemoglobin and oxygen measurements in isolation do not indicate the more physiologically relevant oxygen content per unit blood volume. This can be maintained for SaO2 ≥78.5%, and resets to the same arterial oxygen content after correction of hypoxaemia. Serum iron concentrations, not ferritin, seem to predict more successful polycythaemic responses

Glycogen Synthase Kinase 3 (GSK3) Inhibitor, SB-216763, Promotes Pluripotency in Mouse Embryonic Stem Cells

Canonical Wnt/β-catenin signaling has been suggested to promote self-renewal of pluripotent mouse and human embryonic stem cells. Here, we show that SB-216763, a glycogen synthase kinase-3 (GSK3) inhibitor, can maintain mouse embryonic stem cells (mESCs) in a pluripotent state in the absence of exogenous leukemia inhibitory factor (LIF) when cultured on mouse embryonic fibroblasts (MEFs). MESCs maintained with SB-216763 for one month were morphologically indistinguishable from LIF-treated mESCs and expressed pluripotent-specific genes Oct4, Sox2, and Nanog. Furthermore, Nanog immunostaining was more homogenous in SB-216763-treated colonies compared to LIF. Embryoid bodies (EBs) prepared from these mESCs expressed early-stage markers for all three germ layers, and could efficiently differentiate into cardiac-like cells and MAP2-immunoreactive neurons. To our knowledge, SB-216763 is the first GSK3 inhibitor that can promote self-renewal of mESC co-cultured with MEFs for more than two months

Participant experiences of mindfulness-based childbirth education: a qualitative study

Background: Childbirth is an important transitional life event, but one in which many women are dissatisfied stemming in part from a sense that labour is something that happens to them rather than with them. Promoting maternal satisfaction with childbirth means equipping women with communication and decision making skills that will enhance their ability to feel involved in their labour. Additionally, traditional antenatal education does not necessarily prepare expectant mothers and their birth support partner adequately for birth. Mindfulness-based interventions appear to hold promise in addressing these issues. Mindfulness-based Child Birth Education (MBCE) was a pilot intervention combining skills-based antenatal education and Mindfulness Based Stress Reduction. Participant experiences of MBCE, both of expectant mothers and their birth support partners are the focus of this article. Methods: A generic qualitative approach was utilised for this study. Pregnant women between 18 and 28 weeks gestation, over 18 years of age, nulliparous with singleton pregnancies and not taking medication for a diagnosed mental illness or taking illicit drugs were eligible to undertake the MBCE program which was run in a metropolitan city in Australia. Focus groups with 12 mothers and seven birth support partners were undertaken approximately four months after the completion of MBCE. Audio recordings of the groups were transcribed verbatim and analysed thematically using the method of constant comparison by all four authors independently and consensus on analysis and interpretation arrived at through team meetings.Results: A sense of both ‘empowerment’ and ‘community’ were the essences of the experiences of MBCE both for mothers and their birth support partner and permeated the themes of ‘awakening my existing potential’ and ‘being in a community of like-minded parents’. Participants suggested that mindfulness techniques learned during MBCE facilitated their sense of control during birth, and the content and pedagogical approach of MBCE enabled them to be involved in decision making during the birth. The pedagogical approach also fostered a sense of community among participants which extended into the postnatal period. Conclusions: MBCE has the potential to empower women to become active participants in the birthing process, thus addressing common concerns regarding lack of control and satisfaction with labour and facilitate peer support into the postnatal period. Further education of health professionals may be needed to ensure that they respond positively to those women and birth support partners who remain active in decision making during birth

Single-dose administration and the influence of the timing of the booster dose on immunogenicity and efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine: a pooled analysis of four randomised trials.

BACKGROUND: The ChAdOx1 nCoV-19 (AZD1222) vaccine has been approved for emergency use by the UK regulatory authority, Medicines and Healthcare products Regulatory Agency, with a regimen of two standard doses given with an interval of 4-12 weeks. The planned roll-out in the UK will involve vaccinating people in high-risk categories with their first dose immediately, and delivering the second dose 12 weeks later. Here, we provide both a further prespecified pooled analysis of trials of ChAdOx1 nCoV-19 and exploratory analyses of the impact on immunogenicity and efficacy of extending the interval between priming and booster doses. In addition, we show the immunogenicity and protection afforded by the first dose, before a booster dose has been offered. METHODS: We present data from three single-blind randomised controlled trials-one phase 1/2 study in the UK (COV001), one phase 2/3 study in the UK (COV002), and a phase 3 study in Brazil (COV003)-and one double-blind phase 1/2 study in South Africa (COV005). As previously described, individuals 18 years and older were randomly assigned 1:1 to receive two standard doses of ChAdOx1 nCoV-19 (5 × 1010 viral particles) or a control vaccine or saline placebo. In the UK trial, a subset of participants received a lower dose (2·2 × 1010 viral particles) of the ChAdOx1 nCoV-19 for the first dose. The primary outcome was virologically confirmed symptomatic COVID-19 disease, defined as a nucleic acid amplification test (NAAT)-positive swab combined with at least one qualifying symptom (fever ≥37·8°C, cough, shortness of breath, or anosmia or ageusia) more than 14 days after the second dose. Secondary efficacy analyses included cases occuring at least 22 days after the first dose. Antibody responses measured by immunoassay and by pseudovirus neutralisation were exploratory outcomes. All cases of COVID-19 with a NAAT-positive swab were adjudicated for inclusion in the analysis by a masked independent endpoint review committee. The primary analysis included all participants who were SARS-CoV-2 N protein seronegative at baseline, had had at least 14 days of follow-up after the second dose, and had no evidence of previous SARS-CoV-2 infection from NAAT swabs. Safety was assessed in all participants who received at least one dose. The four trials are registered at ISRCTN89951424 (COV003) and ClinicalTrials.gov, NCT04324606 (COV001), NCT04400838 (COV002), and NCT04444674 (COV005). FINDINGS: Between April 23 and Dec 6, 2020, 24 422 participants were recruited and vaccinated across the four studies, of whom 17 178 were included in the primary analysis (8597 receiving ChAdOx1 nCoV-19 and 8581 receiving control vaccine). The data cutoff for these analyses was Dec 7, 2020. 332 NAAT-positive infections met the primary endpoint of symptomatic infection more than 14 days after the second dose. Overall vaccine efficacy more than 14 days after the second dose was 66·7% (95% CI 57·4-74·0), with 84 (1·0%) cases in the 8597 participants in the ChAdOx1 nCoV-19 group and 248 (2·9%) in the 8581 participants in the control group. There were no hospital admissions for COVID-19 in the ChAdOx1 nCoV-19 group after the initial 21-day exclusion period, and 15 in the control group. 108 (0·9%) of 12 282 participants in the ChAdOx1 nCoV-19 group and 127 (1·1%) of 11 962 participants in the control group had serious adverse events. There were seven deaths considered unrelated to vaccination (two in the ChAdOx1 nCov-19 group and five in the control group), including one COVID-19-related death in one participant in the control group. Exploratory analyses showed that vaccine efficacy after a single standard dose of vaccine from day 22 to day 90 after vaccination was 76·0% (59·3-85·9). Our modelling analysis indicated that protection did not wane during this initial 3-month period. Similarly, antibody levels were maintained during this period with minimal waning by day 90 (geometric mean ratio [GMR] 0·66 [95% CI 0·59-0·74]). In the participants who received two standard doses, after the second dose, efficacy was higher in those with a longer prime-boost interval (vaccine efficacy 81·3% [95% CI 60·3-91·2] at ≥12 weeks) than in those with a short interval (vaccine efficacy 55·1% [33·0-69·9] at <6 weeks). These observations are supported by immunogenicity data that showed binding antibody responses more than two-fold higher after an interval of 12 or more weeks compared with an interval of less than 6 weeks in those who were aged 18-55 years (GMR 2·32 [2·01-2·68]). INTERPRETATION: The results of this primary analysis of two doses of ChAdOx1 nCoV-19 were consistent with those seen in the interim analysis of the trials and confirm that the vaccine is efficacious, with results varying by dose interval in exploratory analyses. A 3-month dose interval might have advantages over a programme with a short dose interval for roll-out of a pandemic vaccine to protect the largest number of individuals in the population as early as possible when supplies are scarce, while also improving protection after receiving a second dose. FUNDING: UK Research and Innovation, National Institutes of Health Research (NIHR), The Coalition for Epidemic Preparedness Innovations, the Bill & Melinda Gates Foundation, the Lemann Foundation, Rede D'Or, the Brava and Telles Foundation, NIHR Oxford Biomedical Research Centre, Thames Valley and South Midland's NIHR Clinical Research Network, and AstraZeneca

Sharing good practice in process safety teaching

The teaching of safety is one of the most important and transferrable subjects in the undergraduate chemical engineering curriculum. However, whilst different institutions have a broadly similar approach to educating students in core topics such as transport processes, approaches to safety teaching are somewhat more variable. This paper describes, analyses and reflects on our approach to safety teaching. It was found that not only are the requirements for accreditation of the degree programme by the Institution of Chemical Engineers (IChemE) met, but the majority of the IChemE Safety Centre’s (ISC) recommendations are also covered. Student feedback on the 3rd year Safety and Loss Prevention (S&LP) module showed that the course has been consistently well received by the students, pointing to good course structure and coherence being a significant factor. Analysis of the outcomes of the 2020 final examination for S&LP, using Bloom’s taxonomy, supported existing plans to change the mode of assessment of S&LP to a significant coursework project. Finally, plans for a future revision of the S&LP module are presented to serve as one exemplar of good practice in safety teaching, which not only meets the requirements of the accrediting body and industry, but is also enjoyed by students

EFFECT OF CLINICALLY ENGAGED ANATOMY CURRICULUM ON DOCTORATE OF PHYSICAL THERAPY STUDENT PERFORMANCE

Matthew P. Condo, Blake Justice, John Fox, Michael Tighe, Matthew Foreman. Methodist University, Fayetteville, NC. BACKGROUND: COVID-19 forced the pedagogical delivery model of anatomy. This study compared test scores in a clinically engaged anatomy curriculum, which integrated the application of anatomic concepts, biomechanics, surface palpation, and dynamic anatomy on physical therapy students. METHODS: The DPT anatomy cohort of 2019 served as the control group for this study and received a traditional model of the anatomy curriculum for half of the fall 2019 semester. The cohort of 2019 finished the fall 2019 semester under a clinically engaged delivery model. The anatomy cohort of 2020 served as the experimental group for this study and received 2.5 hours of virtual, synchronous lecture, 2 hours of cadaver dissection every other week, 4 hours of virtual dissection every other week, and 2 hours of functional/integrated lab time every other week. Each cohort was examined with two written midterm examinations, one midterm lab examination, and cumulative written and lab final examinations. Data analysis of midterm exam scores was performed using R Studio (Version 1.4.1717© 2009-2021 RStudio, PBC). The midterm 1 score for the 2019 cohort was 69.12% and the cohort of 2020 midterm score was 80.1%. The second written midterm scores displayed no significant differences between the 2019 and 2020 cohorts with a mean score of 80.1% and 79.14%, respectively. RESULTS: ANOVA of the 4 midterm scores revealed a significant difference between the midterm 1 score of the 2020 cohort versus the midterm exam scores of the 2019 cohort and the midterm examination two scores of the cohort of 2020 (F(3,156) = 11.31, p \u3c 0.001). The midterm 2 scores of both cohorts demonstrated no significant differences in mean scores and scores in the lower quartiles. A post hoc Tukey test showed that the 2020 cohort’s midterm 1 scores were significantly different from the other groups. CONCLUSIONS: The results of this study further validate previous literature by demonstrating that the number of hours spent in didactic lectures does not explain student performance. Anatomy instructors in physical therapy programs should strive to seek opportunities to apply their curriculum to clinical scenarios and concepts to reinforce learning

Ethologically based behavioural and neurochemical characterisation of mice with isoform-specific loss of dysbindin-1A in the context of schizophrenia

Dysbindin-1 is implicated in several aspects of schizophrenia, including cognition and both glutamatergic and dopaminergic neurotransmission. Targeted knockout of dysbindin-1A (Dys-1A KO), the most abundant and widely expressed isoform in the brain, is associated with deficits in delay/interference-dependent working memory. Using an ethologically based approach, the following behavioural phenotypes were examined in Dys-1A KO mice: exploratory activity, social interaction, anxiety and problem-solving ability. Levels of monoamines and their metabolites were measured in striatum, hippocampus and prefrontal cortex using high-performance liquid chromatography with electrochemical detection. The ethogram of initial exploration in Dys-1A KO mice was characterised by increased rearing from a seated position; over subsequent habituation, stillness was decreased relative to wildtype. In a test of dyadic social interaction with an unfamiliar conspecific in a novel environment, female KO mice showed an increase in investigative social behaviours. Marble burying behaviour was unchanged. Using the puzzle-box test to measure general problem-solving performance, no effect of genotype was observed across nine trials of increasing complexity. Dys-1A KO demonstrated lower levels of 5-HT in ratio to its metabolite 5-HIAA in the prefrontal cortex. These studies elaborate the behavioural and neurochemical phenotype of Dys-1A KO mice, revealing subtle genotype-related differences in non-social and social exploratory behaviours and habituation of exploration in a novel environment, as well as changes in 5-HT activity in brain areas related to schizophrenia