Humility and respect: core values in medical education

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102253/1/medu12269.pd

GlycA, a novel composite pro-inflammatory glycoprotein biomarker, and its relationship with cardiometabolic disorders

Chronic low-grade inflammation is a hallmark of many diseases, including cardiovascular disease, type 2 diabetes and cancer. Acute-phase reactants are commonly measured to assess the severity of inflammation. Many acute phase reactants are heavily glycosylated. A nuclear magnetic resonance (NMR) spectroscopy method, called GlycA, has been recently developed. The measured amplitude reflects the plasma protein glycosylation, the signal comes mainly from the following acute-phase proteins: α1-acid glycoprotein, haptoglobin, α1-antitrypsin and α1-antichymotrypsin. In this thesis, we examined the role of GlycA in the context of the metabolic syndrome, cardiovascular disease, type 2 diabetes, and life expectancy. Overall, the results of this thesis support the contention that this glycoprotein biomarker reflects a pro-inflammatory state, in part alike, but also complementary to an existing marker of inflammation. Noteworthy, GlycA and lipoproteins can be quantified from the same NMR spectra of serum or plasma. Therefore, it is possible to combine GlycA along with standard clinical assessments and other NMR-measured metabolic and lipoprotein biomarkers to increase the specificity of the prediction for progression to cardiovascular diseases or type 2 diabetes. This can be of relevance to guide the selection and intensity of interventions intended to prevent progression to CVD or T2DM

Bioactivity of tempe by inhibiting adhesion of ETEC to intestinal cells, as influenced by fermentation substrates and starter pure cultures

Soya bean tempe is known for its bioactivity in reducing the severity of diarrhoea in piglets. This bioactivity is caused by an inhibition of the adhesion of enterotoxigenic Escherichia coli (ETEC) to intestinal cells. In this paper, we assessed the bioactive effect of soya tempe on a range of ETEC target strains, as well as the effect of a range of cereal and leguminous substrates and starter pure cultures. Soya bean tempe extracts strongly inhibited the adhesion of ETEC strains tested. All tempe made from other leguminous seeds were as bioactive as soya bean tempe, whereas tempe made from cereals showed no bioactivity. Using soya beans as substrate, fermentation with several fungi (Mucor, Rhizopus spp. and yeasts) as well as Bacillus spp. resulted in bioactive tempe, whereas fermentation with lactobacilli showed no bioactivity. The active component is releasedor formed during the fermentation and is not present in microbial biomass and only partly in unfermented substrates. The bioactivity being not specific for a single ETEC strain, makes the bioactive tempe relevant for applications in animal husbandry

Agonistic and antagonistic estrogens in licorice root (Glycyrrhiza glabra)

The roots of licorice (Glycyrrhiza glabra) are a rich source of flavonoids, in particular, prenylated flavonoids, such as the isoflavan glabridin and the isoflavene glabrene. Fractionation of an ethyl acetate extract from licorice root by centrifugal partitioning chromatography yielded 51 fractions, which were characterized by liquid chromatography–mass spectrometry and screened for activity in yeast estrogen bioassays. One third of the fractions displayed estrogenic activity towards either one or both estrogen receptors (ERs; ERa and ERß). Glabrene-rich fractions displayed an estrogenic response, predominantly to the ERa. Surprisingly, glabridin did not exert agonistic activity to both ER subtypes. Several fractions displayed higher responses than the maximum response obtained with the reference compound, the natural hormone 17ß-estradiol (E2). The estrogenic activities of all fractions, including this so-called superinduction, were clearly ER-mediated, as the estrogenic response was inhibited by 20–60% by known ER antagonists, and no activity was found in yeast cells that did not express the ERa or ERß subtype. Prolonged exposure of the yeast to the estrogenic fractions that showed superinduction did, contrary to E2, not result in a decrease of the fluorescent response. Therefore, the superinduction was most likely the result of stabilization of the ER, yeast-enhanced green fluorescent protein, or a combination of both. Most fractions displaying superinduction were rich in flavonoids with single prenylation. Glabridin displayed ERa-selective antagonism, similar to the ERa-selective antagonist RU 58668. Whereas glabridin was able to reduce the estrogenic response of E2 by approximately 80% at 6¿×¿10-6 M, glabrene-rich fractions only exhibited agonistic responses, preferentially on ERa

The ethanolamide metabolite of DHA, docosahexaenoylethanolamine, shows immunomodulating effects in mouse peritoneal and RAW264.7 macrophages: evidence for a new link between fish oil and inflammation

Several mechanisms have been proposed for the positive health effects associated with dietary consumption of long-chain n-3 PUFA (n-3 LC-PUFA) including DHA (22 : 6n-3) and EPA (20 : 5n-3). After dietary intake, LC-PUFA are incorporated into membranes and can be converted to their corresponding N-acylethanolamines (NAE). However, little is known on the biological role of these metabolites. In the present study, we tested a series of unsaturated NAE on the lipopolysaccharide (LPS)-induced NO production in RAW264.7 macrophages. Among the compounds tested, docosahexaenoylethanolamine (DHEA), the ethanolamide of DHA, was found to be the most potent inhibitor, inducing a dose-dependent inhibition of NO release. Immune-modulating properties of DHEA were further studied in the same cell line, demonstrating that DHEA significantly suppressed the production of monocyte chemotactic protein-1 (MCP-1), a cytokine playing a pivotal role in chronic inflammation. In LPS-stimulated mouse peritoneal macrophages, DHEA also reduced MCP-1 and NO production. Furthermore, inhibition was also found to take place at a transcriptional level, as gene expression of MCP-1 and inducible NO synthase was inhibited by DHEA. To summarise, in the present study, we showed that DHEA, a DHA-derived NAE metabolite, modulates inflammation by reducing MCP-1 and NO production and expression. These results provide new leads in molecular mechanisms by which DHA can modulate inflammatory processes

Using evaluation research to improve medical education

Evaluation research is a form of applied research that scrutinises how well a particular programme, practice, procedure or policy is operating. Evaluation researchers use both quantitative and qualitative research data to construct a collective picture of the programme under evaluation.Medical educators need to provide information about a particular programme using the methods of evaluation research in order to make a decision on the potential adoption, improvements and refinements of the programme. Improving curricula and pedagogical methods using these methods may enhance health care education.We provide an overview of the methods of evaluation research in the context of medical education. We discuss the application, general methodology, methods of collecting data and analysis for each type of evaluation research.The methods of evaluation research described in this article enable medical educators to gain a comprehensive understanding of evaluation research in the context of medical education. The use of evaluation research findings helps medical educators to make informed decisions regarding a programme and any future actions related to it.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79207/1/j.1743-498X.2010.00383.x.pd

Aiming for the complete utilization of sugar-beet pulp: Examination of the effects of mild acid and hydrothermal pretreatment followed by enzymatic digestion

<p>Abstract</p> <p>Background</p> <p>Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Lignocellulosic feedstocks often require physicochemical pretreatment before enzymatic hydrolysis can begin. The optimal pretreatment can be different for different feedstocks, and should not lead to biomass destruction or formation of toxic products.</p> <p>Methods</p> <p>We examined the influence of six mild sulfuric acid or water pretreatments at different temperatures on the enzymatic degradability of sugar-beet pulp (SBP).</p> <p>Results</p> <p>We found that optimal pretreatment at 140°C of 15 minutes in water was able to solubilize 60% w/w of the total carbohydrates present, mainly pectins. More severe treatments led to the destruction of the solubilized sugars, and the subsequent production of the sugar-degradation products furfural, hydroxymethylfurfural, acetic acid and formic acid. The pretreated samples were successfully degraded enzymatically with an experimental cellulase preparation.</p> <p>Conclusions</p> <p>In this study, we found that pretreatment of SBP greatly facilitated the subsequent enzymatic degradation within economically feasible time ranges and enzyme levels. In addition, pretreatment of SBP can be useful to fractionate functional ingredients such as arabinans and pectins from cellulose. We found that the optimal combined severity factor to enhance the enzymatic degradation of SBP was between log R'₀= -2.0 and log R'₀= -1.5. The optimal pretreatment and enzyme treatment solubilized up to 80% of all sugars present in the SBP, including ≥90% of the cellulose.</p

Biologische beheersing wortelvlieg (Psila rosae) in 2009

Vanaf 2007 wordt nagegaan of de wortelvlieg in het veld te beheersen is door het toepassen van twee verschillende sterk geurende oliën. De volwassen wortelvlieg vindt een peenperceel met behulp van de geuren die de planten afscheiden. De vraag is of de geur van zo’n peenperceel gemaskeerd kan worden met sterk ruikende plantaardige oliën zodat de wortelvlieg dit perceel niet meer kan vinden. In 2008 waren er aanwijzingen dat uienolie de wortelvliegaantasting kan verminderen. In 2009 zijn op 6 peenpercelen en een perceel wortelpeterselie demonstraties aangelegd om de wortelvliegaantasting te beperken. Op 6 peenpercelen was de aantasting te gering om hier uitspraken over te doen. Het maximaal percentage aangetaste wortels lag voor deze percelen onder de 3%. Op het perceel wortelpeterselie was de aantasting wel voldoende. De oliën hebben een natuurlijke oorsprong (geëxtraheerd uit planten) en worden als geurstof en niet als gewasbeschermingsmiddel gebruikt. Immers de wortelvlieg wordt niet gedood maar misleid. De methode werkt selectief omdat alleen insecten die peen met behulp van geur vinden, worden beïnvloed. Zij hebben meer moeite met het vinden van zo’n peenperceel, of kunnen dit in zijn geheel niet vinden. Indien de methode werkt kan deze zowel in de biologische als in de gangbare teelt gebruikt worden. In 2010 is er meer budget beschikbaar voor onderzoek naar de wortelvlieg waardoor we eind 2010 een beter inzicht hebben of deze methode in de praktijk perspectieven biedt

A longitudinal study of self-assessment accuracy

Although studies have examined medical students' ability to self-assess their performance, there are few longitudinal studies that document the stability of self-assessment accuracy over time. This study compares actual and estimated examination performance for three classes during their first 3 years of medical school. Methods  Students assessed their performance on classroom examinations and objective structured clinical examination (OSCE) stations. Each self-assessment was then contrasted with their actual performance using idiographic (within-subject) methods to define three measures of self-assessment accuracy: bias (arithmetic differences of actual and estimated scores), deviation (absolute differences of actual and estimated scores), and covariation (correlation of actual and estimated scores). These measures were computed for four intervals over the course of 3 years. Multivariate analyses of variance and correlational analyses were used to evaluate the stability of these measures. Results  Self-assessment accuracy measures were relatively stable over the first 2 years of medical school with a decease occurring in the third year. However, the correlational analyses indicated that the stability of self-assessment accuracy was comparable to the stability of actual performance over this same period. Conclusion  The apparent decline in accuracy in the third year may reflect the transition from familiar classroom-based examinations to the substantially different clinical examination tasks of the third year OSCE. However, the stability of self-assessment accuracy compares favorably with the stability of actual performance over this period. These results suggest that self-assessment accuracy is a relatively stable individual characteristic that may be influenced by task familiarity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75505/1/j.1365-2923.2003.01567.x.pd

Relationship Between Symptoms and Health‐Related Quality of Life in Patients Treated for Hypertension

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90331/1/phco.24.4.344.33177.pd