High concentrations of nitrite present in saliva (derived from dietary nitrate) may, upon acidification, generate nitrogen oxides in the stomach in sufficient amounts to provide protection from swallowed pathogens. We now show that, in the rat, reduction of nitrate to nitrite is confined to a specialized area on the posterior surface of the tongue, which is heavily colonized by bacteria, and that nitrate reduction is absent in germ-free rats. We also show that in humans increased salivary nitrite production resulting from nitrate intake enhances oral nitric oxide production. We propose that the salivary generation of nitrite is accomplished by a symbiotic relationship involving nitrate-reducing bacteria on the tongue surface, which is designed to provide host defence against microbial pathogens in the mouth and lower gut. These results provide further evidence for beneficial effects of dietary nitrate.

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Despite numerous studies stretching over the last 100 years there is still no general agreement on the number of auditory areas in the human cortex or even how to define them by histological methods. Full definition of these areas will require a combination of functional and histological methods but, by using six complementary histological methods, of which most have been used in the monkey, we provide a clearer description of these areas. The primary auditory area was located on the posteromedial two-thirds of the first transverse temporal (Heschl's) gyrus and was distinguished by a dense band of cytochrome oxidase activity in layer IV and the base of layer III, as well as a relatively thick, pale layer V and VI. Layers V and VI together made up 40% of the cortical thickness. Acetylcholinesterase (AChE)-containing pyramidal cells were sparsely distributed within the primary auditory area. The anterolateral third of Heschl's gyrus did not have a clear band of high cytochrome oxidase activity but contained a moderately high density of AChE-containing pyramidal cells and thus appeared to be part of the auditory belt. Within Heschl's sulcus there was a third area, which had a band of high cytochrome oxidase activity and bands of high parvalbumin immunoreactivity and AChE activity in layer IV. This area appeared to be part of the auditory core. Thus the use of staining methods for cytochrome oxidase, AChE and parvalbumin provided additional information which allowed a clearer definition of auditory areas than Nissl or myelin staining alone. Our results suggest that there are two core areas surrounded by at least six belt areas in the human auditory region.

BackgroundWorkforce planning is a central issue for service provision and has consequences for medical education. Much work has been examined the career intentions, career preferences and career destinations of UK medical graduates but there is little published about medical students career intentions. How soon do medical students formulate careers intentions? How much do these intentions and preferences change during medical school? If they do change, what are the determining factors? Our aim was to compare medical students’ career preferences upon entry into and exit from undergraduate medical degree programmes.MethodsThis was a cross-sectional questionnaire survey. Two cohorts [2009–10, 2010–11] of first and final year medical students at the four Scottish graduating medical schools took part in career preference questionnaire surveys. Questions were asked about demographic factors, career preferences and influencing factors.ResultsThe response rate was 80.9% [2682/3285]. Significant differences were found across the four schools, most obviously in terms of student origin [Scotland, rest of UK or overseas], age group, and specialty preferences in Year 1 and Year 5. Year 1 and Year 5 students’ specialty preferences also differed within each school and, while there were some common patterns, each medical school had a different profile of students’ career preferences on exit. When the analysis was adjusted for demographic and job-related preferences, specialty preferences differed by gender, and wish for work-life balance and intellectual satisfaction.ConclusionsThis is the first multi-centre study exploring students’ career preferences and preference influences upon entry into and exit from undergraduate medical degree programmes. We found various factors influenced career preference, confirming prior findings. What this study adds is that, while acknowledging student intake differs by medical school, medical school itself seems to influence career preference. Comparisons across medical school populations must therefore control for differences in input [the students] as well as context and process [the medical school] when looking at output [e.g., performance]. A robust, longitudinal study is required to explore how medical students’ career preferences change as they progress through medical school and training to understand the influence of the learning environment on training choice and outcomes.

OBJECTIVES Little is known about the relationship between the career preferences of medical students and the medical schools at which they are enrolled. Our aim was to explore this relationship early in students' medical training. Year 1 (2009Year 1 ( -2010) medical students at the five Scottish medical schools were invited to take part in a career preference questionnaire survey. Questions were asked about demographic factors, career preferences and influencing factors. METHODS RESULTSThe response rate was 87.9% (883 ⁄ 1005). No significant differences were found among medical schools with regard to first-choice specialty. Surgery (22.5%), medicine (19.0%), general practice (17.6%) and paediatrics (16.1%) were the top career choices. Work-life balance, perceived aptitude and skills, intellectual satisfaction, and amount of patient contact were rated as the most important job-related factors by most respondents. Few differences were found among schools in terms of the impact of jobrelated factors on future career preferences. Students for whom the work-life balance was extremely important (odds ratio [OR] = 0.6) were less likely to prefer surgery. Students for whom the work-life balance (OR = 2.2) and continuity of care (OR = 2.1) were extremely important were more likely to prefer general practice.CONCLUSIONS Students' early career preferences were similar across the five medical schools. These preferences result from the interplay among demographic factors and the perceived characteristics of the various specialties. Maintaining a satisfactory work-life balance is very important to tomorrow's doctors, and the data hint that this may be breaking down some of the traditional gender differences in specialty choice. Longitudinal work is required to explore whether students' career preferences change as they progress through medical school and training.