In which sequence? Does it matter?

This article was migrated. The article was marked as recommended. A distinctive feature between the delivery of traditional preclinical and clinical curricula is that discipline-based clinical curriculum is delivered in a series of parallel clinical rotations for different groups of students, whereas the curriculum is synchronized across the cohort in preclinical years. Therefore, the sequence of learning themes or topics is more relevant to the preclinical years compared to clinical years in which the beginning and end points of the curriculum are different from one student to another. Many factors, both pedagogical and logistic, influence the optimal sequence of themes for the preclinical curriculum. During the process of reorganizing the sequence of themes for the preclinical curriculum at the University of Notre Dame Australia Fremantle, we identified a relative gap in literature on this topic. Given the importance of the sequence of themes for learning in the preclinical years, we were surprised to learn that publications on this topic are sparse. While sharing the challenges that we came across in our decision making process, we invite the scholars in this area to share their experience. This will undoubtedly benefit curriculum developers and educators in creating or reviewing the preclinical curriculum at their respective institutions.

Reviewing the preclinical curriculum in a Problem Based Learning driven medical program: challenges and strategies.

This article was migrated. The article was marked as recommended. In order for medical curricula to remain progressive and contemporary, continuous review is critical to ensure that the learners are directed to achieve the intended goals and become workforce ready. We developed a framework for continuous curriculum review at the School of Medicine Fremantle (The University of Notre Dame Australia), taking the key aspects of a curriculum review process into consideration. In planning and implementing the review process we identified several challenges, including management of metadata, work load on staff members, and evaluation. These challenges were addressed successfully by applying necessary strategies using limited resources. The framework we have developed provides a guide to key stakeholders who are involved in medical curriculum review and development.

The role of PKCζ in cord blood T-cell maturation towards Th1 cytokine profile and its epigenetic regulation by fish oil.

While immunodeficiency of immaturity of the neonate has been considered important as the basis for unusual susceptibility to infection, it has also been recognized that the ability to progress from an immature Th2 cytokine predominance to a Th1 profile has relevance in determining whether children will develop allergy, providing an opportunity for epigenetic regulation through environmental pressures. However, this notion remains relatively unexplored. Here, we present evidence that there are two major control points to explain the immunodeficiency in cord blood (CB) T-cells, a deficiency in interleukin (IL)-12 (IL-12) producing and IL-10 overproducing accessory cells, leading to a decreased interferon γ (IFNγ) synthesis and the other, an intrinsic defect in T-cell protein kinase C (PKC) ζ (PKCζ) expression. An important finding was that human CB T-cells rendered deficient in PKCζ, by shRNA knockdown, develop into low tumour necrosis factor α (TNFα) and IFNγ but increased IL-13 producing cells. Interestingly, we found that the increase in PKCζ levels in CB T-cells caused by prenatal supplementation with fish oil correlated with modifications of histone acetylation at the PKCζ gene (PRKCZ) promoter. The data demonstrate that PKCζ expression regulates the maturation of neonatal T-cells into specific functional phenotypes and that environmental influences may work via PKCζ to regulate these phenotypes and disease susceptibility.

Epigenetic Regulation in Early Childhood: A Miniaturized and Validated Method to Assess Histone Acetylation.

INTRODUCTION: Chronic inflammatory diseases including allergies and asthma are the result of complex interactions between genes and environmental factors. Epigenetic mechanisms comprise a set of biochemical reactions that regulate gene expression. In order to understand the cause-effect relationship between environmental exposures and disease development, methods capable of assessing epigenetic regulation (also) in large cohorts are needed. METHODS: For this purpose, we developed and evaluated a miniaturized chromatin immunoprecipitation (ChIP) assay allowing for a cost-effective assessment of histone acetylation of candidate genes in a quantitative fashion. This method was then applied to assess H3 and H4 histone acetylation changes in cord blood (CB) samples from an established cohort of Australian children exposed in the fetal period to either very low or very high levels of maternal folate. RESULTS: Our ChIP assay was validated for a minimum requirement of 1 × 105 target cells (e.g. CD4+ T cells). Very high levels of maternal folate were significantly associated with increased H3/H4 acetylation at GATA3 and/or IL9 promoter regions in CD4+ T cells in CB. CONCLUSION: We developed a ChIP method allowing reliable assessment of H3/H4 acetylation using 1 × 105 cells only. Practical application of this assay demonstrated an association between high maternal folate exposure and increased histone acetylation, corresponding to a more transcriptionally permissive chromatin status in the promoter regions of some Th2-related genes.

Epigenome-wide analysis of neonatal CD4(+) T-cell DNA methylation sites potentially affected by maternal fish oil supplementation.

Supplementation of fish oil rich in omega-3 polyunsaturated fatty acids (n-3 PUFA) during pregnancy has been shown to confer favorable health outcomes in the offspring. In a randomized controlled trial, we have previously shown that n-3 PUFA supplementation in pregnancy was associated with modified immune responses and some markers of immune maturation. However, the molecular mechanisms underlying these heritable effects are unclear. To determine whether the biological effects of maternal n-3 PUFA supplementation are mediated through DNA methylation, we analyzed CD4(+) T-cells purified from cryo-banked cord blood samples from a previously conducted clinical trial. Of the 80 mother-infant pairs that completed the initial trial, cord blood samples of 70 neonates were available for genome-wide DNA methylation profiling. Comparison of purified total CD4(+) T-cell DNA methylation profiles between the supplement and control groups did not reveal any statistically significant differences in CpG methylation, at the single-CpG or regional level. Effect sizes among top-ranked probes were lower than 5% and did not warrant further validation. Tests for association between methylation levels and key n-3 PUFA parameters, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), or total n-3 PUFAs were suggestive of dose-dependent effects, but these did not reach genome-wide significance. Our analysis of the microarray data did not suggest strong modifying effects of in utero n-3 PUFA exposure on CD4(+) T-cell methylation profiles, and no probes on the array met our criteria for further validation. Other epigenetic mechanisms may be more relevant mediators of functional effects induced by n-3 PUFA in early life.

Epigenetics in immune development and in allergic and autoimmune diseases.

Epigenetic mechanisms such as DNA methylation, histone modification, and micro RNA signaling regulate the activity of the genome. Virtually all aspects of immunity involve some level of epigenetic regulation, whether it be host defense or in mediating tolerance. These processes are critically important in mediating dynamic responses to the environment over the life course of the individual, yet we are only just beginning to understand how dysregulation in these pathways may play a role in immune disease. Here, we give a brief chronological overview of epigenetic processes during immune development in health and disease.

Genome-wide DNA methylation profiling identifies a folate-sensitive region of differential methylation upstream of ZFP57-imprinting regulator in humans.

Folate intake during pregnancy may affect the regulation of DNA methylation during fetal development. The genomic regions in the offspring that may be sensitive to folate exposure during in utero development have not been characterized. Using genome-scale profiling, we investigated DNA methylation in 2 immune cell types (CD4(+) and antigen-presenting cells) isolated from neonatal cord blood, selected on the basis of in utero folate exposure. High-folate (HF; n=11) and low-folate (LF; n=12) groups were selected from opposite extremes of maternal serum folate levels measured in the last trimester of pregnancy. A comparison of these groups revealed differential methylation at 7 regions across the genome. By far, the biggest effect observed was hypomethylation of a 923 bp region 3 kb upstream of the ZFP57 transcript, a regulator of DNA methylation during development, observed in both cell types. Levels of H3/H4 acetylation at ZFP57 promoter and ZFP57 mRNA expression were higher in CD4(+) cells in the HF group relative to the LF group. Hypomethylation at this region was replicated in an independent sample set. These data suggest that exposure to folate has effects on the regulation of DNA methylation during fetal development, and this may be important for health and disease.

Nutrition in early life, immune-programming and allergies: the role of epigenetics.

Early life nutritional exposures are significant determinants of the development and future health of all organ systems. The dramatic rise in infant immune diseases, most notably allergy, indicates the specific vulnerability of the immune system to early environmental changes. The associated parallel rise in metabolic diseases including obesity, childhood type 2-diabetes and non-alcoholic fatty liver disease highlights the interplay between modern dietary patterns and increasing abnormalities of both immune and metabolic health. The low-grade inflammation that characterize these non-communicable diseases (NCDs) suggests a central role of the immune system in the pathogenesis of these conditions. Understanding how environmental influences disrupt the finely balanced development of immune and metabolic programing is of critical importance. Diet-sensitive pathways are likely to be crucial in these processes. While epigenetic mechanism provides a strong explanation of how nutritional exposures can affect the fetal gene expression and subsequent disease risk, other diet-induced tissue compositional changes may also contribute directly to altered immune and metabolic function. Although modern dietary changes are complex and involve changing patterns of many nutrients, there is also interest in the developmental effects of specific nutrients such as folic acid levels, which have clear epigenetic effects on programming. Here we examine the current knowledge of the nutritional-programming of immune health and how research into nutritional-epigenetics in the context of allergic disease as one of the earliest onset NCDs can expand our knowledge to discover the biological processes sensitive to nutritional exposures in early life to prevent later disease risk.

Impact of helminth infection on childhood allergic diseases in an area in transition from high to low infection burden.

BACKGROUND: The effect of helminth infections on allergic diseases is still inconclusive. Furthermore, the effect of helminth infections on childhood allergic diseases in a tropical area where prevalence of helminth infections has undergone dramatic changes is not well documented. OBJECTIVE: To investigate the relationship between allergic diseases and helminth infection in a cohort of schoolchildren in an area that has undergone dramatic changes in intensity of helminth infections. METHODS: Children attending grade 5 were recruited from 17 schools in Western Province of Sri Lanka. They were assessed for allergic diseases using the International Study of Asthma and Allergies in Childhood questionnaire. Their serum total IgE (tIgE) and allergen-specific IgE (sIgE) for five common aeroallergens were measured by ImmunoCAP® method and stools were examined for the presence of helminth infections. RESULTS: A total of 640 children (mean age 10 years) were recruited to the study. Of them, 33.7% had evidence of allergic disease and 15.5% had helminth infections. Majority of infections (68.9%) were of low intensity. A significant relationship between allergic disease and helminth infections was not observed, however, a trend toward protective role of helminth infections against allergic diseases was noted. Multivariate analysis showed helminth infections to be an independent predictor of high tIgE levels whereas allergic disease was not. Allergic sensitization (atopy) was a significant risk factor for allergic disease only among non-infected children (odds ratio 3.025, p = 0.022) but not in infected children. The ratio of sIgE to tIgE was higher in non-infected children. CONCLUSION: Though not significant, a reduced risk of allergy in helminth-infected children was observed in this population. A Decrease in intensity of helminth infections may have contributed to the reduced capacity of immune-modulation by helminths in this paediatric population.

Prevalence of latex allergy among healthcare workers.

OBJECTIVES: The use of latex gloves has increased by several folds in the recent past due to concerns about blood-borne infections. Data from Asian countries with regard to latex allergy is scarce. The objective of this study was to determine the prevalence and risk factors of latex allergy among healthcare workers in a tertiary hospital in Sri Lanka. MATERIAL AND METHODS: A cross-sectional survey was carried out among different categories of employees in the hospital. A self-administered questionnaire was used to collect data related to latex allergy. RESULTS: A total of 524 employees was recruited and 62% responded to the questionnaire. Among them 49.2% wore gloves for more than 1 hour a day. Symptoms suggestive of latex allergy were reported by 53 (16.3%) subjects. A considerable proportion (11.4%) of workers had been suffering from latex allergy for more than 5 years. Nurses accounted for the highest prevalence for any job category, while the unit with the highest rate was the surgical ward. Duration in the service (OR = 1.006, P = 0.048) and wearing gloves for more than one hour a day (OR = 3.292, P = 0.004) were significant risk factors for latex allergy, but not atopy or family history of atopy. Seven employees noticed that they developed food allergy after assuming duties as healthcare personnel. CONCLUSIONS: Prevalence of latex allergy is high among healthcare workers in this study population. Environmental factors rather than genetic predisposition play the major role in the development of this condition.