The carbon metabolism of Listeria monocytogenes (Lm) EGD and the two isogenic mutant strains Lm⌬prfA and Lm⌬prfApPRFA* (showing no or enhanced expression, respectively, of the virulence factor PrfA) was determined by 13 C isotopologue perturbation. After growth of the bacteria in a defined medium containing a mixture of [U-13 C6]glucose and glucose with natural 13 C abundance (1:25, wt͞wt), 14 amino acids were isolated and analyzed by NMR spectroscopy. Multiply 13 C-labeled isotopologues were determined quantitatively by signal deconvolution. The 13 C enrichments and isotopologue patterns allowed the reconstruction of most amino acid biosynthesis pathways and illustrated that overproduced PrfA may strongly influence the synthesis of some amino acids, notably that of the branched amino acids (Val, Ile, and Leu). Retrobiosynthetic analysis of the isotopologue compositions showed that degradation of glucose occurs to a large extent via the pentose phosphate pathway and that the citrate cycle is incomplete because of the absence of 2-oxoglutarate dehydrogenase activity. The reconstructed labeling pattern of oxaloacetate indicated its formation by carboxylation of pyruvate. This metabolic reaction seems to have a strong impact on the growth requirement in defined minimal medium. Bioinformatical steady-state network analyses and flux distribution predictions confirmed the experimental data and predicted metabolite fluxes through the enzymes of the pathways under study.NMR analysis ͉ intracellular bacteria ͉ metabolic flux ͉ extracellular metabolom T errestrial carbon is a mixture of Ϸ98.9% 12 C and 1.1% 13 C.In organic matter, the distribution of these isotopes is close to random. All organic compounds are, therefore, complex mixtures of different carbon isotopologues. As an example, a 5-carbon compound consists predominantly of the [U-12 C 5 ] isotopologue, accounting for Ϸ95 mol %. Each of the five isotopologues carrying a single 13 C atom in any position is present at Ϸ1 mol %. Multiply 13 C-substituted species are progressively rare; for example, the [U-13 C 5 ] isotopologue accounts for Ϸ10 Ϫ8 mol %. Minor deviations from the random distribution are caused by geophysical and biological processes and serve as the basis for a variety of scientific studies, such as the geographic origin of materials; however, these deviations are below the sensitivity of the methods used in this article and are, therefore, not discussed further.The quasirandom distribution of carbon isotopes can be experimentally perturbed by the introduction of a 13 C-enriched compound or a mixture of such compounds. In cells and organisms, such a perturbation will rapidly spread through the entire metabolic network. The quantitative analysis of that relaxation process can afford qualitative as well as quantitative information on metabolic processes in the experimental system under study (1-7).As an example for the application of this perturbation͞ relaxation concept, we analyzed the carbon metabolism of Listeria monocytogenes (Lm) after extracellu...

Background: Healthcare systems worldwide have adopted the electronic medical record (EMR). EMRs are an efficient method of interprofessional communication, and can improve data availability for secondary research purposes. The discharge summary (DS) is a crucial document for both interprofessional communication, and coding of data for research purposes. We aimed to assess the completeness of our EMRs by assessing the presence of a DS in the EMR. Additionally, we evaluated the presence of indicators for a missing DS. Method: A retrospective chart review was conducted on 3,011 inpatient charts from 3 hospitals in Calgary, Alberta Canada. 893 charts were missing an electronic DS. A 10% sample was drawn to assess for presence of a paper DS. A list of variables was compiled to assess for association between patient and hospital characteristics, patient comorbidities, and the absence of an electronic DS. A Chi-square test, Fisher's test and logistic regression were conducted to assess for associations. Results: The univariate analyses showed that age, being a surgical patient, a Charlson Comorbidity Index (CCI) of

Over the last few years, major progress in research has improved our understanding of the restless legs syndrome (RLS). Although frequently under-diagnosed, several epidemiological studies have estimated its prevalence in western countries at 4-10% of the general population. Its diagnosis is usually made on a clinical basis, according to the criteria established by the International RLS Study Group (Mov Disord 1995; 10:634). Furthermore, major advances have also been achieved regarding our understanding of the pathophysiology of the disorder. Thus, several brain imaging studies, as well as pharmacological challenges, suggest the presence of a dopaminergic dysfunction playing a major role in its causation. In addition, a strong association has been discovered between brain iron deficiency and RLS. Eventually, dopaminergic drugs have shown therapeutic efficacy in various large-scale therapeutic trials, and, today, dopaminergic agonists represent the first line of treatment. In conclusion, these and other recent findings shed light on our understanding and management of one of the most common movement disorders.

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