Momna Hejmadi

Neuroprotection by nicotine against hypoxia-induced apoptosis in cortical cultures involves activation of multiple nicotinic acetylcholine receptor subtypes

Activation of neuronal nicotinic acetylcholine receptors (nAChR) by nicotine has been suggested to protect neurons against a hypoxic insult. The objective of this study was to examine the nature of cell death induced by acute hypoxia in rat primary cortical cultures and the neuroprotective potential of nicotine in ameliorating these processes. Neuronal cell death induced by a 4-h exposure to hypoxia (0.1% O(2)) was apoptotic, as shown by TUNEL staining and assays monitoring DNA strand breaks and caspase-3/7 activity. The presence of nicotine (10 microM) during the hypoxic insult protected a subpopulation of susceptible neurones against DNA damage and apoptosis induced by oxygen deprivation. This protective effect of nicotine was prevented by a 30-min pre-incubation with either 100 nM alpha-bungarotoxin or 1 microM dihydro-beta-erythroidine, but not 1 microM atropine, suggesting that activation of at least two subtypes of nAChR, alpha7 and beta2* nAChR, is involved in mediating nicotine neuroprotection.

Work placement experience: should I stay or should I go?

The opportunity to experience work placements that complement taught and practical courses in higher education has become a central strand of many undergraduate degree programmes. While there is tacit agreement that such placements are a good thing, in recent years the numbers of students opting for work placements has been declining. This paper uses a mixed method research design to probe the learning outcomes, attitudes and perceptions of undergraduate students who choose not to go on a work placement. Findings highlight some areas of concern that could be considered by institutions of higher education working to enhance good practice in students’ work placement experiences.

L -Glutamate binding sites of parasitic nematodes: an association with ivermectin resistance?

Nematode membrane preparations contain high amounts of low-affinity specific L-glutamate binding sites. The numbers of these sites were increased in 2 isolates, one field-derived and the other laboratory-derived, of ivermectin-resistant Haemonchus contortus and a field isolate of ivermectin-resistant Telodorsagia circumcincta, when compared to control, drug-sensitive isolates. Specific [3H]ivermectin binding to these membrane preparations showed no differences between ivermectin-sensitive and resistant isolates and the number of ivermectin binding sites was approximately 100-fold less than the number of L-glutamate binding sites. Kinetic analysis of L-glutamate binding suggested the presence of at least 2 classes of binding site. L-Glutamate binding was blocked by ibotenic acid, kynurenic acid and beta-hydroxyaspartate, but not by ivermectin, argiopine, kainate, quisqualate or NMDA. Competition assays with ibotenic acid suggested that there were 2 distinct populations of glutamate binding sites and that the site with the lower affinity for ibotenate was upregulated in the ivermectin-resistant nematodes. In the field isolate of resistant H. contortus we found no coding changes in the cDNAs encoding glutamate-gated chloride channel subunits HG2, HG3 and HG4, nor were any changes in channel expression detected using subunit-specific antibodies. The low-affinity binding site is unlikely to be associated with the ivermectin receptor in these nematodes.

Exploring the industrial-placement experience for Mechanical Engineering undergraduates

Abstract This paper explores the attitudes of undergraduate engineers towards work placements in industry. This research also assesses the placement experience in terms of student learning outcomes and future employment aspirations. Quantitative and qualitative data were collected from three groups: (i) those recently returning from a placement; (ii) those yet to go on placement and (iii) those who elected not to go on placement. Semi-structured interviews gathered experiences and perceptions from all three groups and formed the basis of attitude questionnaires distributed to 276 undergraduates at the University of Bath. Students were asked what value they attached to a year in industry, what improvement in personal transferable skills (such as team-working, time-management, communication and learning) they felt was gained and their perception of the placement experience in terms of aspirations of future employment. Factors influencing the decision of whether or not to undertake a placement were explored. The marks of the students in each of the three populations were scrutinised in order to determine any academic differences between the groups and to assess any value added by a placement in terms of improved performance on returning to university. Finally, this paper identifies reasons why undergraduates do not elect to undertake placements, asking if these important decisions are well-informed or otherwise.

Toxic shock syndrome toxin-1 challenges the neuroprotective functions of the choroidal epithelium and induces neurotoxicity

To probe encephalopathy pathogenesis during toxic shock syndrome (TSS), we investigated the fate of bloodborne TSS toxin-1 (TSST-1) as it moves through the choroid plexus epithelium that forms the main blood-cerebrospinal fluid (CSF) barrier and the effect that TSST-1 has on choroidal barrier properties and on cultured neuronal cell viability. TSST-1 showed a slow, diffusional movement across a cellular model of the blood-CSF barrier but did not compromise the integrity of the barrier. Relevant to the acute symptoms of TSS, a combination of human leukocytes and the toxin induced a decrease in CSF clearance of the pyrogenic prostaglandin E(2) (PGE(2)). The direct effects that TSST-1 had on primary cortical neuron cultures and a neuronal cell line involved elevated caspase 3/7 levels, which correlated with an increase in neuronal cell death. The results of the present study suggest that TSST-1 can affect the brain, by inducing both an intracerebral increase in PGE(2) concentration and caspase-dependent neuronal death, which are possibly relevant to long-term intoxication.

Teaching genetics prior to teaching evolution improves evolution understanding but not acceptance

What is the best way to teach evolution? As microevolution may be configured as a branch of genetics, it being a short conceptual leap from understanding the concepts of mutation and alleles (i.e., genetics) to allele frequency change (i.e., evolution), we hypothesised that learning genetics prior to evolution might improve student understanding of evolution. In the UK, genetics and evolution are typically taught to 14- to 16-y-old secondary school students as separate topics with few links, in no particular order and sometimes with a large time span between. Here, then, we report the results of a large trial into teaching order of evolution and genetics. We modified extant questionnaires to ascertain students’ understanding of evolution and genetics along with acceptance of evolution. Students were assessed prior to teaching, immediately post teaching and again after several months. Teachers were not instructed what to teach, just to teach in a given order. Regardless of order, teaching increased understanding and acceptance, with robust signs of longer-term retention. Importantly, teaching genetics before teaching evolution has a significant (p < 0.001) impact on improving evolution understanding by 7% in questionnaire scores beyond the increase seen for those taught in the inverse order. For lower ability students, an improvement in evolution understanding was seen only if genetics was taught first. Teaching genetics first additionally had positive effects on genetics understanding, by increasing knowledge. These results suggest a simple, minimally disruptive, zero-cost intervention to improve evolution understanding: teach genetics first. This same alteration does not, however, result in a significantly increased acceptance of evolution, which reflects a weak correlation between knowledge and acceptance of evolution. Qualitative focus group data highlights the role of authority figures in determination of acceptance.

Is choosing to go on placement a gamble? Perspectives from bioscience undergraduates

In the biosciences, a professional placement experience in academia or industry is intended to contribute to a student’s personal and professional training. While there is a general acknowledgement that a placement experience is beneficial for students, recent years have seen a decline in the number of students choosing to go on placements. Using a mixed‐method research design, this paper explores the attitudes that influence the bioscience students’ decisions on whether or not to undertake a year in a professional placement. Other questions considered in this study were whether placements influence student attitudes towards learning and if students achieve a better degree classification and better employment because of placement. Perspectives from academic staff and employers were compared with student perspectives on the added value of undertaking an extended placement during a period of study at university. While our findings reaffirm some of the perceived advantages of a professional placement in terms of learning and employability, it identifies important factors that influence student decisions not to undertake placements, revealing interesting questions on the placement perspectives between the student, academic tutor and employer.

Improving the Effectiveness and Efficiency of Teaching Large Classes: Development and Evaluation of a Novel e-Resource in Cancer Biology

Abstract This paper describes the development and evaluation of a blended learning resource in the biosciences, created by combining online learning with formal face-face lectures and supported by formative assessments. In order to improve the effectiveness and efficiency of teaching large classes with mixed student cohorts, teaching was delivered through a variety of media which included three main components; (1) an interactive online tutorial, based on the cellular processes of DNA replication, damage and repair in relation to oncogenesis (2) formative assessment in the form of multiple choice questions to allow self evaluation and (3) small group follow-up workshops, to encourage deeper learning. The online tutorial was designed using Flash© software to help conceptualise complex cellular processes in time and space. It was supported by formative quizzes, references and printer-ready notes. Introduction of these resources in 2005 led to significant improvements in summative assessments across all student cohorts compared to scores from 2004. Students highly valued the usefulness of self-paced learning combined with supportive formative assessments which helped enhance the learning process. Teaching in small group workshops that followed on from the tutorials was also more effective, allowing a better interaction with the students, encouraging confidence and deeper learning among students. The efficiency of teaching was also improved with reduced assessment times and less pressure on institutional resources (availability of large lecture halls). This study therefore supports the use of blended learning as a means of improving both the effectiveness and efficiency of large group teaching.

Scientific aptitude better explains poor responses to teaching of evolution than psychological conflicts

It is considered a myth that non-acceptance of scientific consensus on emotive topics is owing to difficulties processing scientific information and is, instead, owing to belief-associated psychological conflicts, the strongest non-acceptors being highly educated. It has been unclear whether these results from adults explain variation in response to school-level teaching. We studied a cohort of UK secondary school students (aged 14–16) and assessed their acceptance and understanding of evolution. In addition, to address their aptitude for science we assessed their understanding of genetics and their teacher-derived assessment of science aptitude. As both models predict, students with low initial evolution acceptance scores showed lower increases in the understanding of evolution. Contrary to conventional wisdom, this effect is better explained by lack of aptitude: before teaching, students with low acceptance had lower understanding of both evolution and of genetics; the low-acceptance students sat disproportionately in the foundation (rather than higher) science classes; low-acceptance students showed lower increments in the understanding of genetics; and student gain in the understanding of evolution correlated positively with gain in the understanding of genetics. We find no evidence either for a role for psychological conflict in determining response to teaching or that strong rejectors are more commonly of a higher ability. From qualitative data we hypothesize that religious students can avoid psychological conflict by adopting a compatibilist attitude. We conclude that there are students recalcitrant to the teaching of science (as currently taught) and that these students are more likely to not accept the scientific consensus. Optimizing methods to teach recalcitrant students is an important avenue for research.Secondary school students in the United Kingdom with lower initial levels of acceptance of evolution show lower increases in understanding of evolution in response to teaching of the topic than those students with initially higher acceptance scores. These lower-acceptance students are more likely to be in teacher-stratified lower-ability classes and also have lower responses to teaching of genetics.

Work placements for bioscience undergraduates: Are they really necessary?

Degree-integrated placements (DIPs) are an important learning experience for many bioscience undergraduates. How these extended experiences will be affected by the proposed changes in higher education funding in the UK is uncertain. This paper explores one bioscience degree programme to investigate the contention that learning outcomes, traditionally attributed to extended undergraduate work placements, can equally well be gained from other strands of teaching in higher education institutions. The research compares two groups of bioscience students: those who have been on a DIP and those who have not. It gauges the acquisition of transferable skills in both workplace settings and also in three other strands of the degree programme. Findings suggest that the broad learning that is gained from a DIP cannot be replicated in other strands of undergraduate experience; nor can it be achieved in less structured types of work experience. Possible reasons for this are discussed.