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111.
Getachew Adam Teketel Yohannes Matthew White Alberto Montaigne Christoph Ulbricht Eckhard Birckner Silke Rathgeber Christian Kästner Harald Hoppe Niyazi Serdar Sariciftci Daniel Ayuk Mbi Egbe 《Macromolecular chemistry and physics.》2014,215(15):1473-1484
Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene)s (PPE‐PPVs) with various thiophene units (thiophene, bithiophene, and 3,4‐ethylenedioxythiophene) at the X position, with the general backbone design (Ph? C?C? X ? C?C? Ph? CH?CH? Ph? CH?CH? ), bearing identical solubilizing side chains at the phenylene rings of the polymers, are synthesized to study the effect of this structural alteration on the properties such as the photophysics, the electrochemical properties, the charge‐carrier mobility, and the morphology of the materials and its impact on their photovoltaic performance. The polymers are obtained in good yields with reasonable molecular weights and show solubility in ordinary organic solvents required for solution‐processing applications. The polymer with a basic thiophene ring at the X positions shows the highest open‐circuit voltage (VOC of 930 mV) and the polymer with a bithiophene unit at the X position shows the highest short‐circuit current density and charge‐carrier mobility, whereas the polymer with 3,4‐ethylenedioxythiophene shows the lowest photovoltaic performance.
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Silbernagel G Rosinger S Grammer TB Kleber ME Winkelmann BR Boehm BO März W 《Atherosclerosis》2012,221(2):551-557
ObjectiveType 2 diabetes represents a major cardiovascular risk factor. However, few studies have addressed the impact of the disease duration on mortality. Thus, we aimed to investigate the predictive value of diabetes duration for all-cause and cardiovascular mortality in subjects undergoing coronary angiography.MethodsWe studied 2455 participants of the LUdwigshafen RIsk and Cardiovascular health study (1768 males/687 females). They had a mean ± standard deviation (SD) age of 63.1 ± 9.0 years (range: 40.0–79.9) and a mean ± SD body mass index of 27.7 ± 4.0 kg/m2. 704 subjects were newly diagnosed with type 2 diabetes according to the 2010 criteria of the American Diabetes Association and 446 subjects had a known history of type 2 diabetes. The mean ± SD duration of the follow-up for all-cause and cardiovascular mortality was 7.4 ± 2.3 years.ResultsA total of 543 deaths occurred during the follow-up. Among these, 343 were accounted for by cardiovascular diseases. The duration of type 2 diabetes was strongly and positively correlated with all-cause and cardiovascular mortality (both P < 0.001). The multivariate adjusted hazard ratios (95% confidence intervals) for cardiovascular mortality compared to subjects without diabetes were 1.76 (1.34–2.32), 2.86 (2.00–4.08), 2.96 (1.85–4.74), and 4.55 (3.24–6.39) for subjects with new onset type 2 diabetes and subjects with known type 2 diabetes (duration ≤5, >5 and ≤10, >10 years), respectively.ConclusionsThe data emphasise the need to consider the diabetes duration for the prediction of mortality in subjects at intermediate to high cardiovascular risk. 相似文献
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Hösel M Broxtermann M Janicki H Esser K Arzberger S Hartmann P Gillen S Kleeff J Stabenow D Odenthal M Knolle P Hallek M Protzer U Büning H 《Hepatology (Baltimore, Md.)》2012,55(1):287-297
Adeno-associated viral vectors (rAAV) are frequently used in gene therapy trials. Although rAAV vectors are of low immunogenicity, humoral as well as T cell responses may be induced. While the former limits vector reapplication, the expansion of cytotoxic T cells correlates with liver inflammation and loss of transduced hepatocytes. Because adaptive immune responses are a consequence of recognition by the innate immune system, we aimed to characterize cell autonomous immune responses elicited by rAAV in primary human hepatocytes and nonparenchymal liver cells. Surprisingly, Kupffer cells, but also liver sinusoidal endothelial cells, mounted responses to rAAV, whereas neither rAAV2 nor rAAV8 were recognized by hepatocytes. Viral capsids were sensed at the cell surface as pathogen-associated molecular patterns by Toll-like receptor 2. In contrast to the Toll-like receptor 9-mediated recognition observed in plasmacytoid dendritic cells, immune recognition of rAAV in primary human liver cells did not induce a type I interferon response, but up-regulated inflammatory cytokines through activation of nuclear factor κB. CONCLUSION: Using primary human liver cells, we identified a novel mechanism of rAAV recognition in the liver, demonstrating that alternative means of sensing rAAV particles have evolved. Minimizing this recognition will be key to improving rAAV-mediated gene transfer and reducing side effects in clinical trials due to immune responses against rAAV. 相似文献
116.
Rüdiger J. Seitz Raimund Kleiser Cathrin M. Bütefisch Silke Jörgens Oliver Neuhaus Hans-Peter Hartung 《Neurocase》2013,19(4):316-325
Abstract The cerebral control of bimanual movements is not completely understood. We investigated a 59-year-old, right-handed man who presented with an acute bimanual coordination deficit. Magnetic resonance imaging showed a lesion involving the entire corpus callosum, which was found on stereotactic biopsy to be an ischemic infarct. Paired-pulse transcranial magnetic stimulation indicated that the patient had a lack of interhemispheric inhibition, while intracortical inhibition in motor cortex of either side was normal. Functional magnetic resonance imaging showed activation of the left SMA, the bilateral motor cortex and anterior cerebellum during spontaneous bimanual thumb-index oppositions, which were uncoupled as evident from simultaneous electromyographic recordings. In contrast, when the bimanual thumb-index oppositions were cued by a visual stimulus, the movements of both hands were tightly correlated. This synchronized activity was accompanied by additional activations bilateral in lateral occipital cortex, dorsal premotor cortex and cerebellum. The data suggest that the visually cued movements of both hands were recoupled by action of a bihemispheric motor network. 相似文献
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Hauke S Heinzow Philipp Lenz Michael Khler Frank Reinecke Hansjrg Ullerich Wolfram Domschke Dirk Domagk Tobias Meister 《World journal of gastroenterology : WJG》2012,18(37):5211-5218
AIM:To determine the clinical outcome and predictors of survival after transjugular intrahepatic portosystemic stent shunt (TIPS) implantation in cirrhotic patients. METHODS:Eighty-one patients with liver cirrhosis and consequential portal hypertension had TIPS implantation (bare metal) for either refractory ascites (RA) (n= 27) or variceal bleeding (VB) (n = 54). Endpoints for the study were:technical success, stent occlusion and stent stenosis, rebleeding, RA and mortality. Clinical records of patients were collected and analysed. Baseline characteristics [e.g., age, sex, CHILD score and the model for end-stage liver disease score (MELD score), underlying disease] were retrieved. The Kaplan-Meier method was employed to calculate survival from the time of TIPS implantation and comparisons were made by log rank test. A multivariate analysis of factors influencing survival was carried out using the Cox proportional hazards regression model. Results were expressed as medians and ranges. Comparisons between groups were performed by using the Mann-Whitney Utest and the χ 2 test as appropriate. RESULTS:No difference could be seen in terms of age, sex, underlying disease or degree of portal pressure gradient (PPG) reduction between the ascites and the bleeding group. The PPG significantly decreased from 23.4 ± 5.3 mmHg (VB) vs 22.1 ± 5.5 mmHg (RA) before TIPS to 11.8 ± 4.0 vs 11.7 ± 4.2 after TIPS implantation (P = 0.001 within each group). There was a tendency towards more patients with stage CHILD A in the bleeding group compared to the ascites group (24 vs 6, P = 0.052). The median survival for the ascites group was 29 mo compared to 60 mo for the bleeding group (P = 0.009). The number of radiological controls for stent patency was 6.3 for bleeders and 3.8 for ascites patients (P = 0.029). Kaplan-Meier calculation indicated that stent occlusion at first control (P = 0.027), ascites prior to TIPS implantation (P = 0.009), CHILD stage (P = 0.013), MELD score (P = 0.001) and those patients not having undergone liver transplantation (P = 0.024) were significant predictors of survival. In the Cox regression model, stent occlusion (P = 0.022), RA (P = 0.043), CHILD stage (P = 0.015) and MELD score (P = 0.004) turned out to be independent prognostic factors of survival. The anticoagulation management (P = 0.097), the porto-systemic pressure gradient (P= 0.460) and rebleeding episodes (P = 0.765) had no significant effect on the overall survival. CONCLUSION:RA, stent occlusion, initial CHILD stage and MELD score are independent predictors of survival in patients with TIPS, speaking for a close follow-up in these circumstances. 相似文献
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Roman Romero‐Ortuno Diarmuid O'Shea Bernard Silke 《Geriatrics & Gerontology International》2012,12(4):703-713
Aim: To identify predictors of negative in‐patient outcomes (prolonged hospital stay and death) in nursing home (NH) residents admitted to the hospital as medical emergencies. Methods: This was a retrospective patient series set at St James's Hospital (Dublin, Ireland). The participants were all NH patients requiring acute medical admission under the on‐call medical team between 1 January 2002 and 31 December 2010. Patient characteristics on admission, such as demographics, comorbidity level, major diagnostic categories, vital signs and laboratory profile, were measured. The outcomes of the study were prolonged hospital stay (≥30 days) and in‐hospital mortality. The characteristics of NH patients were compared with those of non‐NH patients aged ≥65 years. Multivariate analyses were based on generalized estimating equations and classification trees. Results: There were 55 763 acute medical admissions over the period, of which 1938 (3.5%) were from NH. As compared with non‐NH patients aged ≥65 years, NH patients had greater acute illness severity. NH patients had a median length of stay of 7 days, and 17% had a prolonged admission. Their overall mortality rate was 23%. However, the classification analysis showed substantial patient heterogeneity; the subgroup with the highest mortality (54%, n = 100) had positive serum troponin and a respiratory major diagnosis. The lowest mortality rate (4%) was seen in those without positive troponin, urea of 12 mmol/L or less, and albumin of more than 37 mg/L (n = 226). Conclusions: Simple serum markers, such as troponin, urea and albumin, might predict mortality in medically admitted NH patients. This might help health‐care practitioners to anticipate their clinical course at an early stage. Geriatr Gerontol Int 2012; ??: ??–??. 相似文献