229 research outputs found
Dreidimensionale Darstellung und Quantifizierung der Spongiosaarchitektur der distalen Tibia - Vorschläge zur Verankerung von Sprunggelenksprothesen
Dreidimensionale Darstellung der Spongiosaarchitektur der distalen Tibia mit Hilfe von Styropomodelle und Auswertung von CT-Schnitten. Es zeigten sich zwei Haupttrabekelbereiche, einer im dorsomedialen un einer ventrolateralen Bereich der Facies articularis tibiae. Dieses Ergebnis stimmt mit der Verteilung der Mineralisation auf der Facies articularis tibiae überein. Durch Anwendung eines dreidimensionalen Computerprogramms wurden die Ergebnisse an zwei Tibiae überprüft
Strengthening participation through decentralisation: findings on local economic development in Kyrgyzstan
"Decentralisation and local government reform are important elements of many developing countries' efforts to improve state governance. Nonetheless, local governments often appear to be very limited in their ability to meet the high expectations associated with decentralisation and the introduction of local self-government. Kyrgyzstan in Central Asia is a typical example of a country where decentralisation efforts have been on the political agenda for more than a decade but actual results are less than satisfactory. While there is widespread agreement among experts about the diagnosis as such, so far little research has been done on the exact reasons for this situation and their effects on the Kyrgyz Republic's development potential. To address this question, this study analyses one particular aspect of decentralisation in the Kyrgyz Republic, namely its impact on popular participation in the design and implementation of local economic development policies. Proceeding from this analysis, the study derives conclusions and recommendations for the Kyrgyz government and other official bodies, local NGOs and international donors." (author's abstract
Impact of soluble fms-like tyrosine kinase-1 and placental growth factor serum levels for risk stratification and early diagnosis in patients with suspected acute myocardial infarction
Aims Angiogenic factors play an important role in the development of atherosclerosis and show pronounced changes during acute myocardial infarction (AMI). We analysed the impact of placental growth factor (PlGF) and its endogen opponent, soluble fms-like tyrosine kinase-1 (sFlt-1), on clinical outcome and the early diagnosis of AMI. Methods and results This multicentre study enrolled patients presenting with symptoms suggestive of AMI. The final diagnosis was adjudicated by two independent physicians. Levels of sFlt-1 and PlGF were compared with results of a standard troponin T and a novel high-sensitive troponin (hsTnT) assay. Of the 763 patients enrolled, 132 were diagnosed with AMI. Multivariable Cox regression analysis demonstrated sFlt-1 >84 ng/L [hazard ratios (HR) 2.6, 95% confidence intervals (CI) 1.2-5.4, P=0.01] and PlGF >20 ng/L (HR 3.6, 95% CI 1.3-10.4, P=0.02) as predictors for mortality during 1-year follow-up, independent from information provided by troponin T and N-terminal pro-B-type natriuretic peptide (NT-proBNP). However, only sFlt-1 persisted as independent predictor for mortality when analysed together with hsTnT and NT-proBNP, and after adjusting for significant clinical parameters. For the diagnosis of AMI, the combination of troponin T and sFlt-1 improved the performance of troponin T alone and led to a negative predictive value of 98.3% already at time of presentation. However, sFlt-1 and PlGF added only limited diagnostic information when used together with hsTnT. Conclusion Only sFlt-1 but not PlGF provides overall independent prognostic information in patients presenting with symptoms suggestive of AMI. After the introduction of hsTnT in clinical routine, sFlt-1 and PlGF can only add limited diagnostic information for the detection or exclusion of AMI. Clinical Trial Registration Information: ClinicalTrials.gov, NCT0047058
Noncompact Symmetries in String Theory
Noncompact groups, similar to those that appeared in various supergravity
theories in the 1970's, have been turning up in recent studies of string
theory. First it was discovered that moduli spaces of toroidal compactification
are given by noncompact groups modded out by their maximal compact subgroups
and discrete duality groups. Then it was found that many other moduli spaces
have analogous descriptions. More recently, noncompact group symmetries have
turned up in effective actions used to study string cosmology and other
classical configurations. This paper explores these noncompact groups in the
case of toroidal compactification both from the viewpoint of low-energy
effective field theory, using the method of dimensional reduction, and from the
viewpoint of the string theory world sheet. The conclusion is that all these
symmetries are intimately related. In particular, we find that Chern--Simons
terms in the three-form field strength play a crucial role.Comment: 40 pages, phyzzx, CALT-68-179
Effect of oral beta-blocker on short and long-term mortality in patients with acute respiratory failure: results from the BASEL-II-ICU study
Acute respiratory failure (ARF) is responsible for about one-third of intensive care unit (ICU) admissions and is associated with adverse outcomes. Predictors of short- and long-term outcomes in unselected ICU-patients with ARF are ill-defined. The purpose of this analysis was to determine predictors of in-hospital and one-year mortality and assess the effects of oral beta-blockers in unselected ICU patients with ARF included in the BASEL-II-ICU study. The BASEL II-ICU study was a prospective, multicenter, randomized, single-blinded, controlled trial of 314 (mean age 70 (62 to 79) years) ICU patients with ARF evaluating impact of a B-type natriuretic peptide- (BNP) guided management strategy on short-term outcomes. In-hospital mortality was 16% (51 patients) and one-year mortality 41% (128 patients). Multivariate analysis assessed that oral beta-blockers at admission were associated with a lower risk of both in-hospital (HR 0.33 (0.14 to 0.74) P = 0.007) and one-year mortality (HR 0.29 (0.16 to 0.51) P = 0.0003). Kaplan-Meier analysis confirmed the lower mortality in ARF patients when admitted with oral beta-blocker and further shows that the beneficial effect of oral beta-blockers at admission holds true in the two subgroups of patients with ARF related to cardiac or non-cardiac causes. Kaplan-Meier analysis also shows that administration of oral beta-blockers before hospital discharge gives striking additional beneficial effects on one-year mortality. Established beta-blocker therapy appears to be associated with a reduced mortality in ICU patients with acute respiratory failure. Cessation of established therapy appears to be hazardous. Initiation of therapy prior to discharge appears to confer benefit. This finding was seen regardless of the cardiac or non-cardiac etiology of respiratory failure. ClinicalTrials.gov Identifier: NCT00130559
Early diagnosis of acute myocardial infarction in the elderly using more sensitive cardiac troponin assays
Aims To examine the diagnostic accuracy of sensitive cardiac troponin (cTn) assays in elderly patients, since elevated levels with sensitive cTn assays were reported in 20% of elderly patients without acute myocardial infarction (AMI). Methods and results In this multi-centre study, we included 1098 consecutive patients presenting with symptoms suggestive of AMI, 406 (37%) were >70 years old. Measurement of three investigational sensitive cTn assays [Roche high-sensitive cTnT (hs-cTnT), Siemens cTnI-Ultra, and Abbott-Architect cTnI) and the standard assay (Roche cTnT) was performed in a blinded fashion. The final diagnosis was adjudicated by two independent cardiologists. Acute myocardial infarction was the adjudicated final diagnosis in 24% of elderly patients. Among elderly patients without AMI, baseline cTn levels were elevated above the 99th percentile in 51% with Roche hs-cTnT, in 17% with Siemens TnI-Ultra, and 13% with Abbott-Architect cTnI. The diagnostic accuracy as quantified by the area under the receiver operating characteristic (ROC) curve (AUC) was significantly greater for the sensitive cTn assays compared with the standard assay (AUC for Roche hs-cTnT, 0.94; Siemens cTnI-Ultra, 0.95; and Abbott-Architect cTnI, 0.95 vs. AUC for the standard assay, 0.90; P < 0.05 for comparisons). The best cut-offs for the sensitive cTn-assays determined by the ROC-curve in elderly patients differed clearly from those in younger patients. Furthermore, the prognostic value regarding 90-day mortality varied among the sensitive cTn assays. Conclusion Sensitive cTn assays have high diagnostic accuracy also in the elderly. Mild elevations are common in elderly non-AMI patients, therefore the optimal cut-off levels are substantially higher in elderly as compared with younger patients. Furthermore, sensitive cTn assays yielded different prognostic value (ClinicalTrials.gov number, NCT00470587
Early diagnosis of acute myocardial infarction in patients with pre-existing coronary artery disease using more sensitive cardiac troponin assays
Aims We sought to examine the diagnostic and prognostic utility of sensitive cardiac troponin (cTn) assays in patients with pre-existing coronary artery disease (CAD). Methods and results We conducted a multicentre study to examine the diagnostic accuracy of one high-sensitive and two sensitive cTn assays in 1098 consecutive patients presenting with symptoms suggestive of acute myocardial infarction (AMI), of whom 401 (37%) had pre-existing CAD. Measurements of Roche high-sensitive cTnT (hs-cTnT), Siemens cTnI-Ultra, Abbott-Architect cTnI and the standard assay (Roche cTnT) were performed in a blinded fashion. The final diagnosis was adjudicated by two independent cardiologists. Acute myocardial infarction was the final diagnosis in 19% of CAD patients. Among patients with diagnoses other than AMI, baseline cTn levels were elevated above the 99th percentile with Roche hs-cTnT in 40%, with Siemens TnI-Ultra in 15%, and Abbott-Architect cTnI in 13% of them. In patients with pre-existing CAD, the diagnostic accuracy at presentation, quantified by the area under the receiver operator characteristic curve (AUC), was significantly greater for the sensitive cTn assays compared with the standard assay (AUC for Roche hs-cTnT, 0.92; Siemens cTnI-Ultra, 0.94; and Abbott-Architect cTnI, 0.93 vs. AUC for the standard assay, 0.87; P < 0.01 for all comparisons). Elevated levels of cTn measured with the sensitive assays predicted mortality irrespective of pre-existing CAD, age, sex, and cardiovascular risk factors. Conclusion Sensitive cTn assays have high-diagnostic accuracy also in CAD patients. Mild elevations are common in non-AMI patients and test-specific optimal cut-off levels tend to be higher in CAD patients than in patients without history of CAD. Sensitive cTn assays also retain prognostic value. (ClinicalTrials.gov number, NCT00470587
Duality and Global Symmetries
This is a general introduction to duality in field theories. The existence
and breaking of global symmetries is used as a guideline to systematically
prove duality between different field theories. Systems discussed include
abelian and non-abelian T-duality in string theory, abelian and nonabelian
bosonization, and duality for massless and massive antisymmetric tensor field
theories in arbitrary number of dimensions. Open questions regarding these
techniques are also discussed. (Lectures given at 33rd Karpacz Winter School
`Duality: Strings and Fields' .)Comment: 19 pages,latex,espcrc
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Notch Inhibition Allows Oncogene-Independent Generation of iPS Cells
The reprogramming of somatic cells to pluripotency using defined transcription factors holds great promise for biomedicine. However, human reprogramming remains inefficient and relies either on the use of the potentially dangerous oncogenes KLF4 and CMYC or the genetic inhibition of the tumor suppressor gene p53. We hypothesized that inhibition of signal transduction pathways that promote differentiation of the target somatic cells during development might relieve the requirement for non-core pluripotency factors during induced pluripotent stem cell (iPSC) reprogramming. Here, we show that inhibition of Notch greatly improves the efficiency of iPSC generation from mouse and human keratinocytes by suppressing p21 in a p53-independent manner and thereby enriching for undifferentiated cells capable of long-term self-renewal. Pharmacological inhibition of Notch enabled routine production of human iPSCs without KLF4 and CMYC while leaving p53 activity intact. Thus, restricting the development of somatic cells by altering intercellular communication enables the production of safer human iPSCs.Molecular and Cellular BiologyStem Cell and Regenerative Biolog
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