2,949 research outputs found
A qualitative exploratory study: Using medical studentsâ experiences to review the role of a rural clinical attachment in KwaZulu-Natal
Objectives: There are challenges when it is considered that a main role of a rural clinical attachment for medical students is to encourage students to return after graduation to practise in rural areas. This view may lead to the relative neglect of other potential valuable roles with regard to rural exposure. This paper draws on the Force Field Model of teacher development to describe medical studentsâ experiences, illustrate the complexity of interacting factors during rural exposure, caution that experiences cannot be predicted and highlight the positive incentives of a rural clinical attachment.Design: The design was explorative, descriptive and qualitative.Setting: The study setting was a district hospital in rural KwaZulu-Natal.Subjects: The participants were four final-year medical students who had completed a compulsory attachment during their Family Medicine rotation.Outcome measures: Data were collected using photo elicitation and analysed using the Force Field Model.Results: The participants felt that overall the experience was positive. The effect of biography and contextual forces were not as strong as expected. Institutional forces were important and programmatic forces tended to have a negative effect on experiences. The participants particularly enjoyed being acknowledged and felt empathy for the difficult tasks of doctors.Conclusion: The potential role of a clinical attachment may go beyond attracting students to practise in rural areas. The experience can be beneficial, irrespective of where the student decides to practise after graduation. There is a need for a review of the rural attachment curriculum and paedagogy. Caution should be used when screening medical students for suitability to work in rural areas prior to rural exposure.Keywords: rural clinical attachment, family medicine rotation, medical students, experiences, Force Field Mode
Trends in the lifetime risk of developing cancer in Great Britain: comparison of risk for those born from 1930 to 1960
BACKGROUND: Typically, lifetime risk is calculated by the period method using current risks at different ages. Here, we estimate the probability of being diagnosed with cancer for individuals born in a given year, by estimating future risks as the cohort ages. METHODS: We estimated the lifetime risk of cancer in Britain separately for men and women born in each year from 1930 to 1960. We projected rates of all cancers (excluding non-melanoma skin cancer) and of all cancer deaths forwards using a flexible age-period-cohort model and backwards using age-specific extrapolation. The sensitivity of the estimated lifetime risk to the method of projection was explored. RESULTS: The lifetime risk of cancer increased from 38.5% for men born in 1930 to 53.5% for men born in 1960. For women it increased from 36.7 to 47.5%. Results are robust to different models for projections of cancer rates. CONCLUSIONS: The lifetime risk of cancer for people born since 1960 is >50%. Over half of people who are currently adults under the age of 65 years will be diagnosed with cancer at some point in their lifetime
Interfaces between bacterial and eukaryotic "neuroecology"
The sensory capacity of bacteria and macroalgae (seaweeds) is limited with respect to many modalities (visual, auditory) common in "higher" organisms such as animals. Thus, we expect that other modalities, such as chemical signaling and sensing, would play particularly important roles in their sensory ecology. Here, we discuss two examples of chemical signaling in bacteria and seaweeds: (1) the role of chemical defenses and quorum-sensing (QS) regulatory systems in bacterial colonization and infection of the red alga Delisea pulchra and their ecological consequences, and (2) the regulation of dispersal and differentiation by nitric oxide (NO) in bacterial biofilms. Consistent with the goals of neuroecology, in both cases, we investigate the links between specific signal-mediated molecular mechanisms, and ecological outcomes, for populations or assemblages of bacteria or seaweeds. We conclude by suggesting that because of the fundamental role played by chemical signaling in bacteria, bacterial systems, either by themselves or in interactions with other organisms, have much to offer for understanding general issues in neuroecology. Thus, further integration of microbiology with the biology of eukaryotes would seem warranted and is likely to prove illuminating. Š The Author 2011. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved
Two-neutron knockout from neutron-deficient Ar, S, and Si
Two-neutron knockout reactions from nuclei in the proximity of the proton
dripline have been studied using intermediate-energy beams of neutron-deficient
Ar, S, and Si. The inclusive cross sections, and also the
partial cross sections for the population of individual bound final states of
the Ar, S and Si knockout residues, have been determined
using the combination of particle and -ray spectroscopy. Similar to the
two-proton knockout mechanism on the neutron-rich side of the nuclear chart,
these two-neutron removal reactions from already neutron-deficient nuclei are
also shown to be consistent with a direct reaction mechanism.Comment: Phys. Rev. C, rapid communication, in pres
Measuring maternal mortality : an overview of opportunities and options for developing countries
Background:There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015. Methods: Since the launch of the Safe Motherhood Initiative in 1987, new opportunities for data capture have arisen and new methods have been developed, tested and used. This paper provides a pragmatic overview of these methods and the optimal measurement strategies for different developing country contexts. Results: There are significant recent advances in the measurement of maternal mortality, yet also room for further improvement, particularly in assessing the magnitude and direction of biases and their implications for different data uses. Some of the innovations in measurement provide efficient mechanisms for gathering the requisite primary data at a reasonably low cost. No method, however, has zero costs. Investment is needed in measurement strategies for maternal mortality suited to the needs and resources of a country, and which also strengthen the technical capacity to generate and use credible estimates. Conclusion: Ownership of information is necessary for it to be acted upon: what you count is what you do. Difficulties with measurement must not be allowed to discourage efforts to reduce maternal mortality. Countries must be encouraged and enabled to count maternal deaths and act.WJG is funded partially by the University of Aberdeen. OMRC is partially funded by the London School of Hygiene and Tropical Medicine. CS and SA are partially funded by Johns Hopkins University. CAZ is funded by the Health Metrics Network at the World Health Organization. WJG, OMRC, CS and SA are also partially supported through an international research program, Immpact, funded by the Bill & Melinda Gates Foundation, the Department for International Development, the European Commission and USAID
Electron excitation and energy transfer rates for H2O in the upper atmosphere
Recent measurements of the cross sections for electronic state excitations in
H2O have made it possible to calculate rates applicable to these excitation
processes. We thus present here calculations of electron energy transfer rates
for electronic and vibrational state excitations in H2O, as well as rates for
excitation of some of these states by atmospheric thermal and auroral secondary
electrons. The calculation of these latter rates is an important first step
towards our aim of including water into a statistical equilibrium model of the
atmosphere under auroral conditions.Comment: 15 pages, 8 figure
Evo-devo of human adolescence: beyond disease models of early puberty
Despite substantial heritability in pubertal development, much variation remains to be explained, leaving room for the influence of environmental factors to adjust its phenotypic trajectory in the service of fitness goals. Utilizing evolutionary development biology (evo-devo), we examine adolescence as an evolutionary life-history stage in its developmental context. We show that the transition from the preceding stage of juvenility entails adaptive plasticity in response to energy resources, other environmental cues, social needs of adolescence and maturation toward youth and adulthood. Using the evolutionary theory of socialization, we show that familial psychosocial stress fosters a fast life history and reproductive strategy rather than early maturation being just a risk factor for aggression and delinquency. Here we explore implications of an evolutionary-developmental-endocrinological-anthropological framework for theory building, while illuminating new directions for research
Targeted genetic testing for familial hypercholesterolaemia using next generation sequencing:a population-based study
Background<p></p>
Familial hypercholesterolaemia (FH) is a common Mendelian condition which, untreated, results in premature coronary heart disease. An estimated 88% of FH cases are undiagnosed in the UK. We previously validated a method for FH mutation detection in a lipid clinic population using next generation sequencing (NGS), but this did not address the challenge of identifying index cases in primary care where most undiagnosed patients receive healthcare. Here, we evaluate the targeted use of NGS as a potential route to diagnosis of FH in a primary care population subset selected for hypercholesterolaemia.<p></p>
Methods<p></p>
We used microfluidics-based PCR amplification coupled with NGS and multiplex ligation-dependent probe amplification (MLPA) to detect mutations in LDLR, APOB and PCSK9 in three phenotypic groups within the Generation Scotland: Scottish Family Health Study including 193 individuals with high total cholesterol, 232 with moderately high total cholesterol despite cholesterol-lowering therapy, and 192 normocholesterolaemic controls.<p></p>
Results<p></p>
Pathogenic mutations were found in 2.1% of hypercholesterolaemic individuals, in 2.2% of subjects on cholesterol-lowering therapy and in 42% of their available first-degree relatives. In addition, variants of uncertain clinical significance (VUCS) were detected in 1.4% of the hypercholesterolaemic and cholesterol-lowering therapy groups. No pathogenic variants or VUCS were detected in controls.<p></p>
Conclusions<p></p>
We demonstrated that population-based genetic testing using these protocols is able to deliver definitive molecular diagnoses of FH in individuals with high cholesterol or on cholesterol-lowering therapy. The lower cost and labour associated with NGS-based testing may increase the attractiveness of a population-based approach to FH detection compared to genetic testing with conventional sequencing. This could provide one route to increasing the present low percentage of FH cases with a genetic diagnosis
Overexpression of Mcl-1 exacerbates lymphocyte accumulation and autoimmune kidney disease in lpr mice
Cell death by apoptosis has a critical role during embryonic development and in maintaining tissue homeostasis. In mammals,
there are two converging apoptosis pathways: the âextrinsicâ pathway, which is triggered by engagement of cell surface âdeath
receptorsâ such as Fas/APO-1; and the âintrinsicâ pathway, which is triggered by diverse cellular stresses, and is regulated by prosurvival
and pro-apoptotic members of the Bcl-2 family of proteins. Pro-survival Mcl-1, which can block activation of the proapoptotic
proteins, Bax and Bak, appears critical for the survival and maintenance of multiple haemopoietic cell types. To
investigate the impact on haemopoiesis of simultaneously inhibiting both apoptosis pathways, we introduced the vavP-Mcl-1
transgene, which causes overexpression of Mcl-1 protein in all haemopoietic lineages, into Faslpr/lpr mice, which lack functional
Fas and are prone to autoimmunity. The combined mutations had a modest impact on myelopoiesis, primarily an increase in the
macrophage/monocyte population in Mcl-1tg/lpr mice compared with lpr or Mcl-1tg mice. The impact on lymphopoiesis was
striking, with a marked elevation in all major lymphoid subsets, including the non-conventional double-negative (DN) T cells
(TCRβ+
CD4â
CD8â
B220+
) characteristic of Faslpr/lpr mice. Of note, the onset of autoimmunity was markedly accelerated in Mcl-1tg/lpr
mice compared with lpr mice, and this was preceded by an increase in immunoglobulin (Ig)-producing cells and circulating
autoantibodies. This degree of impact was surprising, given the relatively mild phenotype conferred by the vavP-Mcl-1 transgene
by itself: a two- to threefold elevation of peripheral B and T cells, no significant increase in the non-conventional DN T-cell
population and no autoimmune disease. Comparison of the phenotype with that of other susceptible mice suggests that the
development of autoimmune disease in Mcl-1tg/lpr mice may be influenced not only by Ig-producing cells but also other
haemopoietic cell types
- âŚ