On (a, B, c)-ideals in Banach spaces

In this paper we focus on subspaces of Banach spaces that are (a, B, c)-ideals. We study (a, B, c)-ideals in l2∞ and present easily verifiable conditions for a subspace of l2∞ to be an (a, B, c)-ideal. Our main results concern the transitivity of (a, B, c)-ideals. We show that if X is an (a, B, c)-ideal in Y and Y is a (d, E, f)-ideal in Z, then X is a certain type of ideal in Z. Relying on this result, we show that if X is an (a, B, c)-ideal in its bidual, then X is a certain type of ideal in X(2n) for every n ∈ N

Drug transporter regulation in tumors by DNA methylation

Epigenetic alterations, such as aberrant DNA methylation, are a hallmark of cancer. DNA hypermethylation of the promoter region affects, for example, the expression of tumor suppressor genes and is associated with their transcriptional silencing in tumors. A recent report has provided evidence for epigenetic silencing of the multispecific organic cation transporter SLC22A1 in hepatocellular carcinoma. Given the role of this transporter in the cellular uptake of several anticancer drugs, the study provided a novel mechanism to explain the substantial variability in treatment response, and it might provide a new strategy for optimization of pharmacotherapy of hepatocellular carcinoma

Quantitative versions of almost squareness and diameter 2 properties

We introduce a quantitative version (using s ∈ 2 (0; 1]) of almost (local) squareness of Banach spaces. The latter concept (i.e., the s = 1 case) was introduced by Abrahamsen, Langemets, and Lima in 2016. Related diameter 2 properties (local, strong, and symmetric strong) are also relaxed correspondingly. Our note contains some (counter-)examples and results for the s-almost (local) squareness property

In situ Untersuchungen von funktionalisierten und unfunktionalisierten Alkanthiol-Monolagen auf Gold- und Silberoberflächen mittels IR vis Summenfrequenzspektroskopie

In dieser Arbeit wurde der Einfluss verschiedener Lösungsmittel auf selbstorganisierende Monolagen funktionalisierter und unfunktionalisierter Alkanthiole mittels nichtlinear-optischer Schwingungsspektroskopie (Summenfrequenzspektroskopie, SFG) untersucht. Die Spektren von Undekanthiol-Monolagen im Kontakt mit den untersuchten Lösungsmitteln (D2O, CCl4, Hexan) zeigen dabei nur geringe Unterschiede zu den Spektren der Monolage an Luft. Die Filme bleiben auch im Lösungsmittel gut geordnet. Bei der quantitativen Auswertung wurden der Einfluss linear-optischer Effekte sowie der Winkel zwischen Methyl-Endgruppe und Oberflächennormale bestimmt. Nur in Hexan zeigt sich eine Abweichung von der an Luft beobachteten Orientierung. Im Unterschied zu diesen Filmen zeigen sich bei Monolagen oligo(ethylenglykol)-terminierter Alkanthiole (EG3-OMe) drastische Aenderungen beim Kontakt mit den Lösungsmitteln. In einem ersten Schritt wurde durch die Aufnahme von Spektren unterschiedlich deuterierter EG3-OMe-Monolagen sowie durch den Vergleich mit ab-initio-Berechnungen eine Zuordnung der Schwingungsbanden in den Spektren durchgefuehrt. Die Monolagen auf Goldsubstraten zeigen im Lösungsmittel eine deutliche Amorphisierung, die Ordnung geht verloren, während die Monolagen auf Silbersubstraten einen deutlich geringeren Einfluss der Lösungsmittel zeigen

Accuracy and Completeness of Drug Information in Wikipedia: A Comparison with Standard Textbooks of Pharmacology

The online resource Wikipedia is increasingly used by students for knowledge acquisition and learning. However, the lack of a formal editorial review and the heterogeneous expertise of contributors often results in skepticism by educators whether Wikipedia should be recommended to students as an information source. In this study we systematically analyzed the accuracy and completeness of drug information in the German and English language versions of Wikipedia in comparison to standard textbooks of pharmacology. In addition, references, revision history and readability were evaluated. Analysis of readability was performed using the Amstad readability index and the Erste Wiener Sachtextformel. The data on indication, mechanism of action, pharmacokinetics, adverse effects and contraindications for 100 curricular drugs were retrieved from standard German textbooks of general pharmacology and compared with the corresponding articles in the German language version of Wikipedia. Quantitative analysis revealed that accuracy of drug information in Wikipedia was 99.7%+/- 0.2% when compared to the textbook data. The overall completeness of drug information in Wikipedia was 83.8 +/- 1.5% (p<0.001). Completeness varied in-between categories, and was lowest in the category "pharmacokinetics'' (68.0% +/- 4.2%;p<0.001) and highest in the category "indication'' (91.3%+/- 2.0%) when compared to the textbook data overlap. Similar results were obtained for the English language version of Wikipedia. Of the drug information missing in Wikipedia, 62.5% was rated as didactically non-relevant in a qualitative re-evaluation study. Drug articles in Wikipedia had an average of 14.6 +/- 1.6 references and 262.8 +/- 37.4 edits performed by 142.7 +/- 17.6 editors. Both Wikipedia and textbooks samples had comparable, low readability. Our study suggests that Wikipedia is an accurate and comprehensive source of drug-related information for undergraduate medical education

Pioglitazone Prevents Capillary Rarefaction in Streptozotocin-Diabetic Rats Independently of Glucose Control and Vascular Endothelial Growth Factor Expression

Background/Aims: Reduction of capillary network density occurs early in the development of metabolic syndrome and may be relevant for the precipitation of diabetes. Agonists of the peroxisome proliferator-activated receptor (PPAR)-gamma transcription factor are vasculoprotective, but their capacity for structural preservation of the microcirculation is unclear. Methods: Male Wistar rats were rendered diabetic by streptozotocin and treated with pioglitazone in chow for up to 12 weeks. Capillary density was determined in heart and skeletal muscle after platelet endothelial cell adhesion molecule-1 (PECAM-1) immunostaining. Hallmarks of apoptosis and angiogenesis were determined. Results: Capillary density deteriorated progressively in the presence of hyperglycemia (from 971/mm(2) to 475/mm(2) in quadriceps muscle during 13 weeks). Pioglitazone did not influence plasma glucose, left ventricular weight, or body weight but nearly doubled absolute and relative capillary densities compared to untreated controls (1.2 vs. 0.6 capillaries/myocyte in heart and 1.5 vs. 0.9 capillaries/myocyte in quadriceps muscle) after 13 weeks of diabetes. No antiapoptotic or angiogenic influence of pioglitazone was detected while a reduced expression of hypoxia-inducible factor-3 alpha and PPAR coactivator-1 alpha (PGC-1 alpha) mRNA as well as vascular endothelial growth factor (VEGF) protein possibly occurred as a consequence of improved vascularization. Conclusion: Pioglitazone preserves microvascular structure in diabetes independently of improvements in glycemic control and by a mechanism unrelated to VEGF-mediated angiogenesis. Copyright (C) 2012 S. Karger AG, Base

Gene Expression Profiling on Global cDNA Arrays Gives Hints Concerning Potential Signal Transduction Pathways Involved in Cardiac Fibrosis of Renal Failure

Cardiac remodelling with interstitial fibrosis in renal failure, which so far is only poorly understood on the molecular level, was investigated in the rat model by a global gene expression profiling analysis. Sprague–Dawley rats were subjected to subtotal nephrectomy (SNX) or sham operation (sham) and followed for 2 and 12 weeks, respectively. Heart-specific gene expression profiling, with RZPD Rat Unigene-1 cDNA arrays containing about 27 000 gene and EST sequences revealed substantial changes in gene expression in SNX compared to sham animals. Motor protein genes, growth and differentiation markers, and extracellular matrix genes were upregulated in SNX rats. Obviously, not only genes involved in cardiomyocyte hypertrophy, but also genes involved in the expansion of non-vascular interstitial tissue are activated very early in animals with renal failure. Together with earlier findings in the SNX model, the present data suggest the hypothesis that the local renin–angiotensin system (RAS) may be activated by at least two pathways: (a) via second messengers and Gproteins (short-term signalling); and (b) via motor proteins, actins and integrins (longterm signalling). The study documents that complex hybridization analysis yields reproducible and promising results of patterns of gene activation pointing to signalling pathways involved in cardiac remodelling in renal failure. The complete array data are available via http://www.rzpd.de/cgi-bin/services/exp/viewExpressionData.pl.cg

Alterations at the Intercalated Disk Associated with the Absence of Muscle Lim Protein

In this study, we investigated cardiomyocyte cytoarchitecture in a mouse model for dilated cardiomyopathy (DCM), the muscle LIM protein (MLP) knockout mouse and substantiated several observations in a second DCM model, the tropomodulin-overexpressing transgenic (TOT) mouse. Freshly isolated cardiomyocytes from both strains are characterized by a more irregular shape compared with wild-type cells. Alterations are observed at the intercalated disks, the specialized areas of mechanical coupling between cardiomyocytes, whereas the subcellular organization of contractile proteins in the sarcomeres of MLP knockout mice appears unchanged. Distinct parts of the intercalated disks are affected differently. Components from the adherens junctions are upregulated, desmosomal proteins are unchanged, and gap junction proteins are downregulated. In addition, the expression of N-RAP, a LIM domain– containing protein located at the intercalated disks, is upregulated in MLP knockout as well as in TOT mice. Detailed analysis of intercalated disk composition during postnatal development reveals that an upregulation of N-RAP expression might serve as an early marker for the development of DCM. Altered expression levels of cytoskeletal proteins (either the lack of MLP or an increased expression of tropomodulin) apparently lead to impaired function of the myofibrillar apparatus and to physiological stress that ultimately results in DCM and is accompanied by an altered appearance and composition of the intercalated disks