33 research outputs found

    Primary trainee teachers’ talk with primary school science coordinators : Two case studies of primary trainees learning to teach science

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    This thesis concerned the potential influence of talk on learning to teach primary science and was based on two case studies involving primary science trainee teachers and primary school science coordinators. The overall question for the thesis was: how may ‘talk’ with a primary school science coordinator influence a trainee learning to teach science during a placement? This study adopted a lens that acknowledged the importance of people and contexts for learning to teach. Extant research on science coordinators’ responsibilities, talk features and mentoring literature, as well as my own background as a science teacher and teacher educator informed and framed the study. A collective instrumental case study provided a methodological context for gathering qualitative data from interactions between two primary school trainee teachers and two science coordinators in primary schools. These participants were in two primary schools where the trainees were placed during the second year of a Bachelor of Education degree at a university in the Midlands, England. A participant observation strategy combined with a semi-structured interview protocol and participants’ reflective diaries were employed as research instruments. Three linguistic features of talk were analysed: topics in sequences of utterances, types of utterances spoken by the science coordinator and ‘we-statements’ spoken by trainees and science coordinators. Eight common topics emerged with science coordinators giving more information than instructions or questions and employing the use of ‘we- statements’ more than trainees. Trainees’ ‘I-statements’ altered during the placement. Factors influencing linguistic features included science coordinators’ prior experiences of ITT mentoring, school practices in teaching science, and topics of talk. The study findings suggest three main ways in which talk may influence a trainee learning to teach science in a primary school. Firstly, talk may influence trainees ‘thinking and doing’ science; secondly, talk may influence trainees’ perceptions about their ‘achievements’ and thirdly, talk may influence trainees’ feelings about science teaching. In making explicit how trainee teachers and science coordinators talk, this study helps to inform how talk may influence learning to teach primary science. From the findings, a new analogy emerged to support an understanding of ‘scaffolded’ learning for trainees through their zone of proximal development (ZPD) (Vygotsky, 1978): ‘talk molecules’. ‘Talk molecules’ visualise linguistic features of talk for a particular topic such that multiple ‘talk molecules’ create a ‘talk space’ which may act as stimuli for learning. This new analogy contributes new knowledge to an understanding of how talk may influence a trainee learning to teach science

    Cediranib combined with carboplatin and paclitaxel in patients with metastatic or recurrent cervical cancer (CIRCCa): a randomised, double-blind, placebo-controlled phase 2 trial

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    Background: Patients treated with standard chemotherapy for metastatic or relapsed cervical cancer respond poorly to conventional chemotherapy (response achieved in 20–30% of patients) with an overall survival of less than 1 year. High tumour angiogenesis and high concentrations of intratumoural VEGF are adverse prognostic features. Cediranib is a potent tyrosine kinase inhibitor of VEGFR1, 2, and 3. In this trial, we aimed to assess the effect of the addition of cediranib to carboplatin and paclitaxel chemotherapy in patients with metastatic or recurrent cervical cancer. Methods: In this randomised, double-blind, placebo-controlled phase 2 trial, which was done in 17 UK cancer treatment centres, patients aged 18 years or older initially diagnosed with metastatic carcinoma or who subsequently developed metastatic disease or local pelvic recurrence after radical treatment that was not amenable to exenterative surgery were recruited. Eligible patients received carboplatin AUC of 5 plus paclitaxel 175 mg/m2 by infusion every 3 weeks for a maximum of six cycles and were randomised centrally (1:1) through a minimisation approach to receive cediranib 20 mg or placebo orally once daily until disease progression. The stratification factors were disease site, disease-free survival after primary therapy or primary stage IVb disease, number of lines of previous treatment, Eastern Cooperative Oncology Group performance status, and investigational site. All patients, investigators, and trial personnel were masked to study drug allocation. The primary endpoint was progression-free survival. Efficacy analysis was by intention to treat, and the safety analysis included all patients who received at least one dose of study drug. This trial is registered with the ISCRTN registry, number ISRCTN23516549, and has been completed. Findings: Between Aug 19, 2010, and July 27, 2012, 69 patients were enrolled and randomly assigned to cediranib (n=34) or placebo (n=35). After a median follow-up of 24·2 months (IQR 21·9–29·5), progression-free survival was longer in the cediranib group (median 8·1 months [80% CI 7·4–8·8]) than in the placebo group (6·7 months [6·2–7·2]), with a hazard ratio (HR) of 0·58 (80% CI 0·40–0·85; one-sided p=0·032). Grade 3 or worse adverse events that occurred in the concurrent chemotherapy and trial drug period in more than 10% of patients were diarrhoea (five [16%] of 32 patients in the cediranib group vs one [3%] of 35 patients in the placebo group), fatigue (four [13%] vs two [6%]), leucopenia (five [16%] vs three [9%]), neutropenia (10 [31%] vs four [11%]), and febrile neutropenia (five [16%] vs none). The incidence of grade 2–3 hypertension was higher in the cediranib group than in the control group (11 [34%] vs four [11%]). Serious adverse events occurred in 18 patients in the placebo group and 19 patients in the cediranib group. Interpretation: Cediranib has significant efficacy when added to carboplatin and paclitaxel in the treatment of metastatic or recurrent cervical cancer. This finding was accompanied by an increase in toxic effects (mainly diarrhoea, hypertension, and febrile neutropenia)

    In vivo single cell analysis reveals Gata2 dynamics in cells transitioning to hematopoietic fate

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    Cell fate is established through coordinated gene expression programs in individual cells. Regulatory networks that include the Gata2 transcription factor play central roles in hematopoietic fate establishment. Although Gata2 is essential to the embryonic development and function of hematopoietic stem cells that form the adult hierarchy, little is known about the in vivo expression dynamics of Gata2 in single cells. Here, we examine Gata2 expression in single aortic cells as they establish hematopoietic fate in Gata2Venus mouse embryos. Time-lapse imaging reveals rapid pulsatile level changes in Gata2 reporter expression in cells undergoing endothelial-to-hematopoietic transition. Moreover, Gata2 reporter pulsatile expression is dramatically altered in Gata2+/- aortic cells, which undergo fewer transitions and are reduced in hematopoietic potential. Our novel finding of dynamic pulsatile expression of Gata2 suggests a highly unstable genetic state in single cells concomitant with their transition to hematopoietic fate. This reinforces the notion that threshold levels of Gata2 influence fate establishment and has implications for transcription factor-related hematologic dysfunctions

    Application of Microarray and Functional-Based Screening Methods for the Detection of Antimicrobial Resistance Genes in the Microbiomes of Healthy Humans

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    The aim of this study was to screen for the presence of antimicrobial resistance genes within the saliva and faecal microbiomes of healthy adult human volunteers from five European countries. Two non-culture based approaches were employed to obviate potential bias associated with difficult to culture members of the microbiota. In a gene target-based approach, a microarray was employed to screen for the presence of over 70 clinically important resistance genes in the saliva and faecal microbiomes. A total of 14 different resistance genes were detected encoding resistances to six antibiotic classes (aminoglycosides, β-lactams, macrolides, sulphonamides, tetracyclines and trimethoprim). The most commonly detected genes were erm(B), blaTEM, and sul2. In a functional-based approach, DNA prepared from pooled saliva samples was cloned into Escherichia coli and screened for expression of resistance to ampicillin or sulphonamide, two of the most common resistances found by array. The functional ampicillin resistance screen recovered genes encoding components of a predicted AcrRAB efflux pump. In the functional sulphonamide resistance screen, folP genes were recovered encoding mutant dihydropteroate synthase, the target of sulphonamide action. The genes recovered from the functional screens were from the chromosomes of commensal species that are opportunistically pathogenic and capable of exchanging DNA with related pathogenic species. Genes identified by microarray were not recovered in the activity-based screen, indicating that these two methods can be complementary in facilitating the identification of a range of resistance mechanisms present within the human microbiome. It also provides further evidence of the diverse reservoir of resistance mechanisms present in bacterial populations in the human gut and saliva. In future the methods described in this study can be used to monitor changes in the resistome in response to antibiotic therapy
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