Impulsphotolytische Untersuchungen zum Mechanismus der photochemischen WOLFF-Umlagerung

9,10-Diazophenanthrone undergoes WOLFF rearrangement in alcoholic solvents and yields esters of 9-fluorene carboxylic acid. By flash light photolysis four intermediates could be detected. Kinetic measurements showed that the ketene formed by photolysis reacts with the solvent to give a cyclopentadienylic carbanion, which is protonated. A carbene or an oxirene intermediate could not be found

Triphenylmethylradikale durch inverse Stevens-Umlagerung

Diphenyldiazomethane reacts with triphenylborane to yield benzophenonazine and benzophenone triphenylmethylhydrazone. The formation of the latter is elucidated by ESR spectroscopic detection of the triphenylmethyl radical. The reaction can be modified to a simple method for the preparation of triphenylmethyl radicals in high yield

Klinische Bedeutung des intraoperativen Schnellschnittverfahrens beim Adenokarzinom des Magens

In der vorliegenden Studie wurde untersucht, ob für die Patienten und Patientinnen, die durch eine Nachresektion tumorfreie Resektionsränder aufwiesen, ein Überlebensvorteil generiert werden konnte. Die 3-Jahres-Überlebensrate (3-JÜR) war in der Gruppe der tumorfreien Resektionsränder ohne Nachresektion mit 62,3% signifikant höher als mit 21,8% in der Gruppe mit tumorfreien Resektionsrändern durch Nachresektion (p <0,001). Vielmehr zeigten nachresezierte Patienten und Patientinnen ein ähnliches Gesamtüberleben wie Patienten und Patientinnen, bei denen keine tumorfreien Resektionsränder erzielt werden konnten (R1) (3- JÜR 21,8% und 13,3%; p=0,792). Die geringe Überlebensrate nach Nachresektion kann möglicherweise durch die fortgeschrittenen Tumorstadien ((y)pT3-4 92,3%; p <0,001) und die Tumorlokalisation (GEJ 73,1%; p<0,001) erklärt werden. Darüber hinaus wurde die Rate der falsch negativen Schnellschnitt Befunde eruiert. Sie lag bei 4,4%. Mit Hinblick auf die Ergebnisse kann die Hypothese aufgestellt werden, dass die falsch-negativen Ergebnisse für die Patienten und Patientinnen möglicherweise keinen Nachteil darstellten, da die erweiterte Resektion im Outcome keinen Überlebensvorteil zeigte. Zusammenfassend konnte gezeigt werden, dass insbesondere Patienten und Patientinnen mit einem fortgeschrittenem Adenokarzinom des Magens und gastroösophagealen Übergangs von einer intraoperative Schnellschnittuntersuchung (IOS) und der anschließenden Resektionserweiterung möglicherweise nicht profitieren. Prospektive Studien werden erforderlich sein, diese Ergebnisse zu bestätigen

Elevated plasma heparin-binding protein is associated with early death after resuscitation from cardiac arrest

Background: An intense systemic inflammatory response is observed following reperfusion after cardiac arrest. Heparin-binding protein (HBP) is a granule protein released by neutrophils that intervenes in endothelial permeability regulation. In the present study, we investigated plasma levels of HBP in a large population of patients resuscitated from out-of-hospital cardiac arrest. We hypothesized that high circulating levels of HBP are associated with severity of post-cardiac arrest syndrome and poor outcome. Methods: Plasma was obtained from 278 patients enrolled in a prospective multicenter observational study in 21 intensive care units (ICU) in Finland. HBP was assayed at ICU admission and 48 h later. Multiple organ dysfunction syndrome (MODS) was defined as the 24 h Sequential Organ Failure Assessment (SOFA) score >= 12. ICU death and 12-month Cerebral Performance Category (CPC) were evaluated. Multiple linear and logistic regression tests and receiver operating characteristic curves with area under the curve (AUC) were performed. Results: Eighty-two percent of patients (229 of 278) survived to ICU discharge and 48 % (133 of 276) to 1 year with a favorable neurological outcome (CPC 1 or 2). At ICU admission, median plasma levels of HBP were markedly elevated, 15.4 [9.6-31.3] ng/mL, and persisted high 48 h later, 14.8 [9.8-31.1] ng/mL. Admission levels of HBP were higher in patients who had higher 24 h SOFA and cardiovascular SOFA score (p <0.0001) and in those who developed MODS compared to those who did not (29.3 [13.7-60.1] ng/mL vs. 13.6 [9.1-26.2] ng/mL, p <0.0001; AUC = 0.70 +/- 0.04, p = 0.0001). Admission levels of HBP were also higher in patients who died in ICU (31.0 [17.7-78.2] ng/mL) compared to those who survived (13.5 [9.1-25.5] ng/mL, p <0.0001) and in those with an unfavorable 12-month neurological outcome compared to those with a favorable one (18.9 [11.3-44.3] ng/mL vs. 12.8 [8.6-30.4] ng/mL, p <0.0001). Admission levels of HBP predicted early ICU death with an AUC of 0.74 +/- 0. 04 (p <0.0001) and were independently associated with ICU death (OR [95 %CI] 1.607 [1.076-2.399], p = 0.020), but not with unfavorable 12-month neurological outcome (OR [95 %CI] 1.154 [0.834-1.596], p = 0.387). Conclusions: Elevated plasma levels of HBP at ICU admission were independently associated with early death in ICU.Peer reviewe

High-sensitivity troponin assays for the early rule-out or diagnosis of acute myocardial infarction in people with acute chest pain: a systematic review and cost-effectiveness analysis.

BACKGROUND: Early diagnosis of acute myocardial infarction (AMI) can ensure quick and effective treatment but only 20% of adults with emergency admissions for chest pain have an AMI. High-sensitivity cardiac troponin (hs-cTn) assays may allow rapid rule-out of AMI and avoidance of unnecessary hospital admissions and anxiety. OBJECTIVE: To assess the clinical effectiveness and cost-effectiveness of hs-cTn assays for the early (within 4 hours of presentation) rule-out of AMI in adults with acute chest pain. METHODS: Sixteen databases, including MEDLINE and EMBASE, research registers and conference proceedings, were searched to October 2013. Study quality was assessed using QUADAS-2. The bivariate model was used to estimate summary sensitivity and specificity for meta-analyses involving four or more studies, otherwise random-effects logistic regression was used. The health-economic analysis considered the long-term costs and quality-adjusted life-years (QALYs) associated with different troponin (Tn) testing methods. The de novo model consisted of a decision tree and Markov model. A lifetime time horizon (60 years) was used. RESULTS: Eighteen studies were included in the clinical effectiveness review. The optimum strategy, based on the Roche assay, used a limit of blank (LoB) threshold in a presentation sample to rule out AMI [negative likelihood ratio (LR-) 0.10, 95% confidence interval (CI) 0.05 to 0.18]. Patients testing positive could then have a further test at 2 hours; a result above the 99th centile on either sample and a delta (Δ) of ≥ 20% has some potential for ruling in an AMI [positive likelihood ratio (LR+) 8.42, 95% CI 6.11 to 11.60], whereas a result below the 99th centile on both samples and a Δ of < 20% can be used to rule out an AMI (LR- 0.04, 95% CI 0.02 to 0.10). The optimum strategy, based on the Abbott assay, used a limit of detection (LoD) threshold in a presentation sample to rule out AMI (LR- 0.01, 95% CI 0.00 to 0.08). Patients testing positive could then have a further test at 3 hours; a result above the 99th centile on this sample has some potential for ruling in an AMI (LR+ 10.16, 95% CI 8.38 to 12.31), whereas a result below the 99th centile can be used to rule out an AMI (LR- 0.02, 95% CI 0.01 to 0.05). In the base-case analysis, standard Tn testing was both most effective and most costly. Strategies considered cost-effective depending upon incremental cost-effectiveness ratio thresholds were Abbott 99th centile (thresholds of < £6597), Beckman 99th centile (thresholds between £6597 and £30,042), Abbott optimal strategy (LoD threshold at presentation, followed by 99th centile threshold at 3 hours) (thresholds between £30,042 and £103,194) and the standard Tn test (thresholds over £103,194). The Roche 99th centile and the Roche optimal strategy [LoB threshold at presentation followed by 99th centile threshold and/or Δ20% (compared with presentation test) at 1-3 hours] were extendedly dominated in this analysis. CONCLUSIONS: There is some evidence to suggest that hs-CTn testing may provide an effective and cost-effective approach to early rule-out of AMI. Further research is needed to clarify optimal diagnostic thresholds and testing strategies. STUDY REGISTRATION: This study is registered as PROSPERO CRD42013005939. FUNDING: The National Institute for Health Research Health Technology Assessment programme

Britisch-Kaffraria und seine deutschen Siedlungen

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