Tuning fresh: radiation through rewiring of central metabolism in streamlined bacteria

Most free-living planktonic cells are streamlined and in spite of their limitations in functional flexibility, their vast populations have radiated into a wide range of aquatic habitats. Here we compared the metabolic potential of subgroups in the Alphaproteobacteria lineage SAR11 adapted to marine and freshwater habitats. Our results suggest that the successful leap from marine to freshwaters in SAR11 was accompanied by a loss of several carbon degradation pathways and a rewiring of the central metabolism. Examples for these are C1 and methylated compounds degradation pathways, the Entner–Doudouroff pathway, the glyoxylate shunt and anapleuretic carbon fixation being absent from the freshwater genomes. Evolutionary reconstructions further suggest that the metabolic modules making up these important freshwater metabolic traits were already present in the gene pool of ancestral marine SAR11 populations. The loss of the glyoxylate shunt had already occurred in the common ancestor of the freshwater subgroup and its closest marine relatives, suggesting that the adaptation to freshwater was a gradual process. Furthermore, our results indicate rapid evolution of TRAP transporters in the freshwater clade involved in the uptake of low molecular weight carboxylic acids. We propose that such gradual tuning of metabolic pathways and transporters toward locally available organic substrates is linked to the formation of subgroups within the SAR11 clade and that this process was critical for the freshwater clade to find and fix an adaptive phenotype.This work was supported by the Swedish Research Council (Grant Numbers 2012-4592 to AE and 2012-3892 to SB) and the Communiy Sequencing Programme of the US Department of Energy Joint Genome Institute. The work conducted by the US Department of Energy Joint Genome Institute, a DOE Office of Science User Facility, is supported under Contract No. DE-AC02-05CH11231

Comparing the effect of hydroxyethyl starch 130/0.4 with balanced crystalloid solution on mortality and kidney failure in patients with severe sepsis (6S-Scandinavian Starch for Severe Sepsis/Septic Shock trial): Study protocol, design and rationale for a double-blinded, randomised clinical trial

Peer reviewe

Samordnad vårdplanering -sett ur en sjuksköterskas perspektiv

Syftet med studien var att belysa sjuksköterskans uppfattning av samordnad vårdplanering som ett fenomen. Studien är en kvalitativ empirisk studie och intervjuer användes som metod. Dessa spelades in på band, transkriberades, analyserades, tolkades av författarna och resulterade i fyra övergripande teman. Urvalet bestod av åtta sjuksköterskor med olika lång yrkeserfarenhet som representerade två olika kliniker. Båda könen ingick i urvalet. Resultaten visade att grundtanken med samordnad vårdplanering var bra men det organisatoriska ifrågasattes. Sjuksköterskan reagerade på att det visades dålig respekt för patientens delaktighet, autonomi och integritet i samband med dessa möten. De gemensamma resurserna verkade otillräckliga, för att ge en fortsatt god och trygg omsorg i människors liv. En administrativt tidskrävande arbetsuppgift som sjuksköterskan är ålagd att hantera i sitt dagliga arbete. Slutsatser blev att sjuksköterskans möjligheter att påverka vårdplaneringens utgång är små och därför uppfattas det som ett komplicerat arbetsmoment. Tidskrävande då vårdplaneringens administrativa del tar mycket av en sjuksköterskas dagliga arbetstid.The aim of this study was to emphasize the nurse’s knowledge of the coordinated care planning as a phenomenon. This is an empirical qualitative study, we have used interviews as a method and the analysed our own. The results were four global themes. The selections consisted of eight nurses whit different various work and they represent two different clinics. Both sexes were represented. The results show that the basic idea with coordinated care planning was good but the organization skills was missing The nurse in charge reacted because the patients did not get involved in the activity, autonomic and was not showed any personal integrity at the meetings. Te common resources seemed insufficient to give a continued good and confident care in these people’s lives. The lack of time was due to the administrative deskwork that the nurses will be able to do daily. The conclusion became that the nurses possibility to influence the planning’s outcome is very small. Due to this it was seen a boring work moment. The lack of administrative care planning, take much time from the daily routine work

Modestly degraded microarchitecture and high serum levels of osteopontin in Swedish females with anorexia nervosa

Purpose Adult women with long-time anorexia nervosa (AN) are believed to have osteopenia (T-score &amp;lt;= 1.0) in 93 % and osteoporosis (T-score &amp;lt;= 2.5) in 38 %. Bone microarchitecture assessed by Trabecular Bone Score (TBS) predicts osteoporotic fractures. Our aim was to evaluate the microarchitecture in adult females with AN by determining TBS and to identify factors potentially associated with TBS, such as bone turnover markers. Methods 20 female patients with AN (DSM IV), aged 27.8 +/- 4.4 years, BMI 16.6 +/- 0.6 kg/m(2) and duration of illness of 8.5 +/- 5 years had previously been evaluated with dual-energy X-ray absorptiometry (DXA). TBS measurements were now obtained, using iNsight software, from spinal DXA images. Serum levels of bone turnover markers were determined in patients and healthy normal-weight controls. Results Compared to controls serum values of osteopontin were higher (p = 0.009). BMD in patients with AN was reduced by at least 1.0 SD at one or more skeletal sites in 65 % of patients and by at least 2.5 SD in 20 %. Only one of the patients (5%) had suffered a fracture. TBS (mean 1.35 +/- 0.06; median 1.36 (1.23-1.44) was in the lower normal range (&amp;gt;= 1.35). 40 % of patients showed partially (&amp;gt; 1.20 and &amp;lt; 1.35) but none showed a fully degraded micro-architecture. Conclusions In Swedish AN patients we found a low reduction of BMD and fracture history. The bone microarchitecture, evaluated for the first time for this group by TBS, was only modestly compromised, and to a lesser extent than expected for this group of patients with AN.Funding Agencies|Linnaeus University; Medical Research Council of Southeast Sweden (FORSS)</p

Characterization of a Hemoglobin Adduct from Ethyl Vinyl Ketone Detected in Human Blood Samples

Electrophiles have the ability to form adducts to nucleophilic sites in proteins and DNA. Internal exposure to such compounds thus constitutes a risk for toxic effects. Screening of adducts using mass spectrometric methods by adductomic approaches offers possibilities to detect unknown electrophiles present in tissues. Previously, we employed untargeted adductomics to detect 19 unknown adducts to N-terminal valine in hemoglobin (Hb) in human blood. This article describes the characterization of one of these adducts, which was identified as the adduct from ethyl vinyl ketone (EVK). The mean adduct level was 40 ± 12 pmol/g Hb in 12 human blood samples; adduct levels from acrylamide (AA) and methyl vinyl ketone (MVK) were quantified for comparison. Using l-valine <i>p</i>-nitroanilide (Val-<i>p</i>NA), introduced as a model of the N-terminal valine, the rate of formation of the EVK adduct was studied, and the rate constant determined to 200 M^–1h^–1 at 37 °C. In blood, the reaction rate was too fast to be feasibly measured, EVK showing a half-life <1 min. Parallel experiments with AA and MVK showed that the two vinyl ketones react approximately 2 × 10³ times faster than AA. The EVK-Hb adduct was found to be unstable, with a half-life of 7.6 h. From the mean adduct level measured in human blood, a daily dose (area under the concentration–time-curve, <i>AUC</i>) of 7 nMh EVK was estimated. The <i>AUC</i> of AA from intake via food is about 20 times higher. EVK is naturally present in a wide range of foods and is also used as a food additive. Most probably, naturally formed EVK is a major source to observed adducts. Evaluation of available toxicological data and information on occurrence of EVK indicate that further studies of EVK are motivated. This study illustrates a quantitative strategy in the initial evaluation of the significance of an adduct detected through adduct screening

Texter om PBL – teori, praktik, reflektioner

Centrum för undervisning och lärande (CUL