126 research outputs found

    Synthese von Aluminium und Galliumhydraziden

    Full text link
    Ziel dieser Arbeit war die Synthese neuer Hydrazide der Elemente Aluminium und Gallium. Dabei gelang es durch Wasserstoffeliminierung die ersten beiden cis-stĂ€ndigen Aluminiumhydrazide zu isolieren. Ebenfalls konnte ein Aluminiumhydrazid mit einer bisher nicht gekannten KĂ€figstruktur erhalten werden. Des weiteren gelang die Synthese eines tetrameren Hydrazides mit KristallkanĂ€len, in denen sich LösungsmittelmolekĂŒle einlagern können. Es konnte gezeigt werden, dass die Wasserstoffeliminierung bevorzugt ablĂ€uft, wenn beide Möglichkeiten zur Reaktion (Wasserstoffeliminierung und Hydroaluminierung) gegeben sind. Bei diesen Versuchen wurde eine interessante Verbindung aus Aluminiumalkylen und einem ausgedehnten Stickstoff-Kohlenstoff-Heterozyklensystem gebildet. Durch Hydroaluminierungsreaktionen konnte zum einen ein interessantes zwitterionisches Hydrazidderivat erhalten werden, zum anderen gelang unter vollstĂ€ndiger Hydroaluminierung die Synthese eines bizyklischen Hydrazides

    Circulating de novo lipogenesis fatty acids and all-cause mortality in a prospective Dutch population cohort

    Get PDF
    Background: Circulating fatty acids (FA) from de novo lipogenesis (DNL) are associated with all-cause mortality in individuals with elevated CVD risk. However, compared to FA early in the DNL synthetic pathway, cis-vaccenic acid, one of the FA distal in the DNL synthetic pathway, has rarely been studied in a general population cohort. We hypothesized that circulating cis-vaccenic acid is more strongly related to all-cause mortality than other circulating DNL-related FA. Objectives: The primary and secondary objectives of this study were to investigate the prospective associations of plasma levels of cis-vaccenic acid and other DNL-related FA with all-cause mortality in a general population, respectively. Methods: We included 850 participants (mean ± SD age 53 ± 15 years) from the Dutch Lifelines cohort study. Circulating levels of palmitic (C16:0), palmitoleic (C16:1n7), cis-vaccenic (cis-C18:1n7), stearic (C18:0), oleic acid (C18:1n9) in plasma phospholipids (PL) and triglycerides (TG) were measured by gas chromatography. The associations of circulating cis-C18:1n7 and other DNL-related FA with all-cause mortality were assessed using Cox regression analyses. Results: During a median follow-up of 9.3 (IQR: 5.4–10.8) years, 34 (4.0%) participants had died. In plasma PL, a 1-SD increase in cis-C18:1n7 was associated with an increased risk of all-cause mortality in univariate and multivariate models (p<0.02 for all), with a HR [95% CI] of 1.60 [1.13–2.25] after adjustment for age and sex. Conclusions: Circulating plasma PL cis-C18:1n7 was associated with a higher risk for all-cause mortality. More studies are needed in different cohorts to verify and validate our results

    Plasma phospholipid fatty acid profile, estimated desaturase activities and prevalence of the metabolic syndrome in a general population cohort:A cross-sectional study

    Get PDF
    BACKGROUND: An altered plasma fatty acid (FA) profile and desaturase activities have been associated with several metabolic diseases, including the MetS, but studies in the general populations are lacking, and only few studies have investigated a broad spectrum of FA in plasma phospholipids (PL). OBJECTIVE: We investigated, cross-sectionally, the relationship of the FA profile and desaturase activities in plasma PL with the prevalence of MetS in a general population in The Netherlands. METHODS: Baseline characteristic data from 850 participants (Male: 50.2%) aged 38-68 years recruited in the Lifelines Cohort study were obtained. The FA profile was determined in fasting plasma PL, and desaturase activities were estimated from product/precursor ratios. The MetS was defined according to International Diabetes Federation. Logistic regressions were used to examine the relation of the FA profile with the prevalence of MetS, and Bonferroni correction was applied to account for multiple testing. RESULTS: 151 participants (17.7%) had the MetS. After adjustment for several confounders and Bonferroni correction, higher tertiles of C18 : 0 (the early precursor of de novo lipogenesis pathway), C18 : 3n6 and C20 : 3n6 (both consistent with a high Δ 6 desaturase (D6D) activity), and D6D activity itself were associated with a higher prevalence of MetS, while higher tertiles of C18 : 1n7, C24 : 0, and C24 : 1n9 (very-long-chain FA) as well as stearoyl-CoA desaturase (SCD)-18 were inversely associated with the MetS. CONCLUSIONS: This study shows that a wide-ranging plasma PL FA profile and estimated desaturase activities were different between adults with and without the MetS in a general representative population and implicates the importance of monitoring individual FAs and desaturase activities as novel modifiable biomarkers for the MetS

    Low circulating concentrations of very long chain saturated fatty acids are associated with high risk of mortality in kidney transplant recipients

    Get PDF
    Kidney transplant recipients (KTR) are at increased risk of mortality, particularly from infectious diseases, due to lifelong immunosuppression. Although very long chain saturated fatty acids (VLSFA) have been identified as crucial for phagocytosis and clearance of infections, their association with mortality in immunocompromised patient groups has not been studied. In this prospective cohort study we included 680 outpatient KTR with a functional graft ≄1 year and 193 healthy controls. Plasma VLSFA (arachidonic acid (C20:0), behenic acid (C22:0) and lignoceric acid (C24:0)) were measured by gas chromatography coupled with a flame ionization detector. Cox regression analyses was used to prospectively study the associations of VLSFA with all-cause and cause-specific mortality. All studied VLSFA were significantly lower in KTR compared to healthy controls (all p < 0.001). During a median (interquartile range) follow-up of 5.6 (5.2–6.3) years, 146 (21%) KTR died, of which 41 (28%) died due to infectious diseases. In KTR, C22:0 was inversely associated with risk of all-cause mortality, with a HR (95% CI) per 1-SD-increment of 0.79 (0.64–0.99), independent of adjustment for potential confounders. All studied VLSFA were particularly strongly associated with mortality from infectious causes, with respective HRs for C20:0, C22:0 and C24:0 of 0.53 (0.35–0.82), 0.48 (0.30–0.75), and 0.51 (0.33–0.80), independent of potential confounders. VLSFA are inversely associated with infectious disease mortality in KTR after adjustment, including HDL-cholesterol. Further studies are needed to assess the effect of VLSFA-containing foods on the risk of infectious diseases in immunocompromised patient groups

    Plasma creatine concentration is associated with incident hypertension in a cohort enriched for the presence of high urinary albumin concentration:the Prevention of Renal and Vascular Endstage Disease study

    Get PDF
    : Hypertension is a major risk factor for cardiovascular disease, kidney disease, and premature death. Increased levels of creatine kinase are associated with development of hypertension. However, it is unknown if creatine, a substrate of CK, is associated with the development of hypertension. We therefore, aimed to investigate the association between plasma creatine concentration and incident hypertension. METHODS: We measured fasting plasma creatine concentrations by nuclear magnetic resonance spectroscopy in participants of the population-based PREVEND study. The study outcome was incident hypertension, defined as either a SBP of at least 140 mmHg, a DBP of at least 90 mmHg, or the new usage of antihypertensive drugs. Participants with hypertension at baseline were excluded. RESULTS: We included 3135 participants (46% men) aged 49 ± 10 years. Mean plasma creatine concentrations were 36.2 ± 17.5 Όmol/l, with higher concentrations in women than in men (42.2 ± 17.6 versus 29.2 ± 17.6 Όmol/l; P < 0.001). During a median of 7.1 [interquartile range: 3.6–7.6] years of follow-up, 927 participants developed incident hypertension. Higher plasma creatine concentrations were associated with an increased risk of incident hypertension [HR per doubling of plasma creatine: 1.21 (95% confidence interval: 1.10–1.34); P < 0.001], which remained significant after adjustment for potential confounders. Sex-stratified analyses demonstrated higher plasma creatine that was independently associated with an increased risk of incident hypertension in men [hazard ratio: 1.26 (95% CI 1.11–1.44); P < 0.001], but not in women (hazard ratio: 1.13 (95% CI 0.96–1.33); P = 0.14]. Causal pathway analyses demonstrate that the association was not explained by sodium or protein intake. CONCLUSION: Higher plasma creatine is associated with an increased risk of hypertension in men. Future studies are warranted to determine the underlying mechanisms

    Factors influencing the practice of new graduate nurses : a focused ethnography of acute care settings

    Full text link
    Aim: To explore the influence of an acute care setting on competency deployment of new graduate nurses (NGNs) from a competency -based undergraduate programme . Background: In the last 15 years, nursing education has shifted to competency -based education (CBE). Few studies have focused on how NGNs from these reformed programmes use the competencies they have developed. To be paradigmatically coherent with the nature of a competence, studies should also examine how context influences nursing practice and competency deployment. Design: A focused ethnography of three acute care units from one academic hospital in Canada. Methods: Purposive and snowball sampling strategies were used to recruit 19 participants: NGNs (n = 4), nurse preceptors (n = 2), clinical nurse specialists (n = 9) , and nurse managers (n = 4). Data were collected through individual interviews, focus groups , observation and documentation. Data were analysed according to Roper and Shapira’s (2000) ethnographic nursing analysis framework. Results: Organizational and individual factors were identified as influencing NGNs ’ competenc y deployment. Organizational factors are orientation, stability, workload, and the scientific culture of the unit. Personal factors have been linked to groups of professionals: for NGNs, personality and clinical placements during their initial education; for nurses working with NGNs, to be role models, to promote integration and to denounce bullying; and for other health professionals, to recognize nursing expertise. Conclusion: One way to s mooth the transition from academic to clinical settings for NGNs is by offering transition or orientation programmes that will provide them with stability and a reduced workload, allowing them to progressively deploy their competencies. Relevance to clinical practice: Organizational and individual factors influence how new graduate nurses deploy their competencies. Clinical educators and nurse managers can help new nurses by acting on these factors

    Consulting completed: temporal aspects of expertise in urban development during times of fast policies

    No full text
    Consultants, especially management consultants with their expertise in markets and entrepreneurial thinking, have gained a new role in urban policy. Urban politicians, facing ever-increasing international competition as well as diverse urban crises, search for immediate solutions, at times drawing on professional advice. This paper introduces the role of management consultants in urban policy in the context of fast policies. These new policies are often both developed over short periods of time and built upon predesigned concepts. Taking six German cities as examples, I frame the impact both of the duration of consultancy projects and of the moment when the consultants leave as temporal aspects of expertise that significantly influence how the external knowledge eventually shapes local political practices. I show that short-term consulting first causes a stimulus for change but then primarily results in an ambivalent amalgamation of professionalization and selectivity as permanently fast modes of everyday policymaking
    • 

    corecore