julilili42/papers huggingface dataset:
High‐Temperature Chlorination‐Reduction Sequence for the Preparation of Silicon Hydride Modified Silica Surfaces
2008-12-12

Abstract A general method for the functionalization of silica surfaces with silicon hydride (Si–H) groups is described for four different preparations of silica. The silica surface is reduced in a two‐step chlorination–reduction procedure within a simple gas‐flow system at high temperatures. After initial dehydroxylation of the silica surface, silicon chloride groups are formed by the reaction with thionyl chloride. The chlorination activates otherwise inaccessible surface siloxane moieties. A high silicon–hydride surface concentration results from the subsequent reduction of the chlorinated surface with hydrogen. The physical properties of the resulting silica are analyzed using scanning electron microscopy, as well as dynamic light scattering and Brunauer–Emmet–Teller measurements. The chlorination–reduction sequence has no significant impact on the structure, surface area and mesopore size of the silica materials used. The surface of the materials is characterized by diffuse reflectance infrared Fourier transform (DRIFT) and 29 Si CP/MAS NMR spectroscopy. The silicon–hydride groups are mostly of the ‐type. The use of high temperatures (&gt;800 °C) results in the condensation of internal and surface silanol groups. Therefore, materials with both a fully condensed silica matrix as well as a surface free of silanol groups are obtained. The materials are ideal precursors for further molecular silica surface modification, as demonstrated with a ferrocene derivative.
Early excision of congenital melanocytic nevi under tumescent anesthesia and skin expansion by intracutaneous double butterfly sutures
2008-12-12

Summary Background: Excision of large congenital melanocytic nevi is recommended because of the risk of malignant transformation and for aesthetic reasons. Our treatment concept includes 1) excision in one or more steps preferably before the age of one year, 2) skin expansion through high‐tension wound closure with intracutaneous double butterfly sutures and 3) performing surgery with tumescent or general anesthesia. Patients and Methods: A retrospective survey was conducted among all parents with children treated for congenital melanocytic nevi in 2004 or 2005 with a maximum age of 6.0 years. The parents were asked to evaluate the trauma associated with their child's surgery and the aesthetic result. Results: Fifty‐nine families were contacted, of whom 51 replied. Forty‐two parents assessed surgery‐associated trauma as light or very light. Thirty‐nine parents rated the aesthetic results as good to very good. Severe complications did not occur. Conclusion: The proposed surgical concept is a safe procedure with good aesthetic results and low surgery‐associated trauma for the child.
Aspect‐oriented component assembly—a case study in parallel software design
2008-12-12

Abstract In this paper we deal with building parallel programs based on sequential application code and generic components providing specific functionality for parallelization, like load balancing or fault tolerance. We describe an architectural approach employing aspect‐oriented programming to assemble arbitrary object‐oriented components. Several non‐trivial crosscutting concerns arising from parallelization are addressed in the light of different applications, which are representative of the most common types of parallelism. In particular, we demonstrate how aspect‐oriented techniques allow us to leave all existing code untouched. We evaluate and compare our approach with its counterparts in conventional object‐oriented programming. Copyright © 2008 John Wiley &amp; Sons, Ltd.
ChemInform Abstract: Metal‐Assisted Oxidative Cyclization of Arylamidrazones. Part 2. Novel Synthesis of 1,4‐Diaryl[1,2,4]triazino[6,5‐h]quinolines.
2008-12-12

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Muscle-Derived Angiopoietin-Like Protein 4 Is Induced by Fatty Acids via Peroxisome Proliferator–Activated Receptor (PPAR)-δ and Is of Metabolic Relevance in Humans
2008-12-16

OBJECTIVE— Long-chain fatty acids (LCFAs) contribute to metabolic homeostasis in part via gene regulation. This study's objective was to identify novel LCFA target genes in human skeletal muscle cells (myotubes). RESEARCH DESIGN AND METHODS— In vitro methods included culture and treatment of human myotubes and C2C12 cells, gene array analysis, real-time RT-PCR, Western blotting, ELISA, chromatin immunoprecipitation, and RNA interference. Human subjects (two cohorts) were characterized by oral glucose tolerance test, hyperinsulinemic-euglycemic clamp, magnetic resonance imaging and spectroscopy, and standard blood analyses (glucose, insulin, C-peptide, and plasma lipids). RESULTS— We show here that ANGPTL4 (encoding angiopoietin-like protein 4) represents a prominent LCFA-responsive gene in human myotubes. LCFA activated peroxisome proliferator-activated receptor (PPAR)-δ, but not PPAR-α or -γ, and pharmacological activation of PPAR-δ markedly induced ANGPTL4 production and secretion. In C2C12 myocytes, knockdown of PPARD, but not of PPARG, blocked LCFA-mediated ANGPTL4 induction, and LCFA treatment resulted in PPAR-δ recruitment to the ANGPTL4 gene. In addition, pharmacological PPAR-δ activation induced LIPE (encoding hormone-sensitive lipase), and this response crucially depended on ANGPTL4, as revealed by ANGPTL4 knockdown. In a human cohort of 108 thoroughly phenotyped subjects, plasma ANGPTL4 positively correlated with fasting nonesterified fatty acids (P = 0.0036) and adipose tissue lipolysis (P = 0.0012). Moreover, in 38 myotube donors, plasma ANGPTL4 levels and adipose tissue lipolysis in vivo were reflected by basal myotube ANGPTL4 expression in vitro (P = 0.02, both). CONCLUSIONS— ANGPTL4 is produced by human myotubes in response to LCFA via PPAR-δ, and muscle-derived ANGPTL4 seems to be of systemic relevance in humans.
Polymorphisms within the Novel Type 2 Diabetes Risk Locus MTNR1B Determine β-Cell Function
2008-12-16

In conclusion, common genetic variation within MTNR1B determines glucose-stimulated insulin secretion and plasma glucose concentrations. Their impact on beta-cell function might represent the prevailing pathomechanism how MTNR1B variants increase the type 2 diabetes risk.
Regulators of G‐protein signalling are modulated by bacterial lipopeptides and lipopolysaccharide
2008-12-16

Regulators of G‐protein signalling accelerate the GTPase activity of G α subunits, driving G proteins in their inactive GDP‐bound form. This property defines them as GTPase activating proteins. Here the effect of different Toll‐like receptor agonists on RGS1 and RGS2 expression in murine bone marrow‐derived macrophages and J774 cells was analysed. After stimulation with TLR2/1 or TLR2/6 lipopeptide ligands and the TLR4/MD2 ligand lipopolysaccharide, microarray analyses show only modulation of RGS1 and RGS2 among all the regulators of G‐protein signalling tested. Real‐time PCR confirmed modulation of RGS1 and RGS2. In contrast to RGS2, which was always downregulated, RGS1 mRNA was upregulated during the first 30 min after stimulation, followed by downregulation. Similar results were also found in the murine macrophage cell line J774. The ligand for intracellular TLR9 modulates RGS1 and RGS2 in a similar manner. However, the TLR3 ligand poly(I:C) permanently upregulates RGS1 and RGS2 expression indicating a different modulation by the MyD88‐ and TRIF‐signalling pathway. This was confirmed using MyD88 −/− and TRIF −/− bone marrow‐derived macrophages. Modulation of RGS1 and RGS2 by Toll‐like receptor ligands plays an important role during inflammatory and immunological reactions after bacterial and viral infection.
Controlling molecular broadband-emission by optical confinement
2008-12-16

We investigate experimentally and theoretically the fluorescence emitted by molecular ensembles as well as spatially isolated, single molecules of an organic dye immobilized in a quasi-planar optical microresonator at room temperature. The optically excited dipole emitters couple simultaneously to on- and off-axis cavity resonances of the microresonator. The multi-spectral radiative contributions are strongly modified with respect to free (non-confined) space due to enhancement and inhibition of the molecular spontaneous emission (SpE) rate. By varying the mirror spacing of the microresonator on the nanometer-scale, the SpE rate of the cavity-confined molecules and, consequently, the spectral line width of the microresonator-controlled broadband fluorescence can be tuned by up to one order of magnitude. Stepwise reducing the optical confinement, we observe that the microresonator-controlled molecular fluorescence line shape converges towards the measured fluorescence line shape in free space. Our results are important for research on and application of broadband emitters in nano-optics and -photonics as well as microcavity-enhanced (single molecule) spectroscopy.
Models of Oral and Vaginal Candidiasis Based on In Vitro Reconstituted Human Epithelia for the Study of Host-Pathogen Interactions
2008-12-16

This protocol describes the setup, maintenance, and characteristics of models of oral and vaginal candidiasis based on well-established three-dimensional organotypic tissues of human oral and vaginal mucosa. Infection experiments are highly reproducible and can be used for the direct analysis of pathogen/epithelial cell interactions. Using the models, the several stages of infection by wild-type Candida albicans strains, the consequence of gene disruption of putative virulence factors in mutant cells, and the evaluation of the host immune response can be evaluated by histologic, biochemical, and molecular methods. As such, the models provide clear answers regarding protein and gene expression that are not complicated by nonepithelial factors. To study the impact of several host components, the mucosal infection models can be supplemented with immune cells, saliva, and probiotic bacteria, which might be relevant for host defense. It requires at least 3 days to be established and can be maintained thereafter for 2 to 4 days.
Experimental Infection of Rodent Mammals for Fungal Virulence Testing
2008-12-16

Invasive fungal infections comprise a group of serious and life-threatening diseases affecting immunocompromised patients. Molecular analysis of fungal virulence involves the deletion of genes that are suspected for contributing to fungal pathogenesis. Phenotypic analysis of the generated mutants includes in vivo infection experiments in order to assign a function during fungal disease to a gene of interest.
Elution kinetics, antimicrobial efficacy, and degradation and microvasculature of a new gentamicin‐loaded collagen fleece
2008-12-17

Abstract Management of bone and soft tissue infections generally includes surgical procedures as well as attendant treatment and prevention with gentamicin‐loaded fleeces. Conventional gentamicin‐containing collagen fleeces currently in use are strongly acidic and exhibit limited biocompatibility thereby adversely affecting wound healing. To improve the antibiotic delivery system, a new phosphate‐buffered, gentamicin‐loaded fleece with pH–neutral properties has been developed (Jason G®). This study aimed at comparing the elution kinetics of gentamicin release and the antimicrobial efficacy of conventional fleeces with the newly developed fleece in vitro . In addition, degradation and microvasculature of implanted fleeces were examined in a rat model and assessed using histology, as well as detection of ED‐1 and PECAM‐expression using immunohistochemistry. We show that the phosphate‐buffered fleeces have reduced release ( p &lt; 0.05) of the integrated gentamicin. However, all of the fleeces tested had a significant antimicrobial effect on the growth of Staphylococcus aureu s, Escherichia coli, and Pseudomonas aeruginosa strains ( p &lt; 0.01). Among the fleeces tested, the new Jason G® fleece had the weakest but nevertheless sufficient antimicrobial effectiveness. Evaluation of the antibiotic effect in the prevention of an infection showed no differences between the applied fleeces. Following surgical implantation of fleece in the backs of Wistar rats we observed, on day 5 after implantation, an increase in cell infiltration and microvascularization with the phosphate‐buffered fleece as compared with conventional fleeces, which show necrotic cells on their surface. Unlike the acidic fleeces, on day 15 after implantation the pH–neutral fleece was resorbed widely. Here, we show that the new, pH–neutral, gentamicin‐containing fleece Jason G® exhibits good overall antimicrobial effectiveness against both gram‐positive and gram‐negative bacteria in vitro with improved degradation properties and microvasculature formation in vivo . © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Platelet interaction with progenitor cells: vascular regeneration or inquiry?
2008-12-18

Increasing evidence supports the role of stem and progenitor cells in vascular regeneration or injury. Following tissue ischemia, progenitor cells are mobilized from their bone marrow or peripheral niches into circulation, adhere at sites of vascular lesion and differentiate into a variety of mature cell types according to their origin and the local environment. Impairment in this pathophysiological process due to either low numbers of circulating progenitor cells or dysfunctional progenitor cells leads to inadequate vascular repair and upon co-existence with different cardiovascular risk factors to vascular injury and atherosclerosis. Vascular repair is a complex process which includes mobilization, chemotaxis, adhesion, proliferation and differentiation of progenitor cells. The common cardiovascular risk factors can impair this process resulting into inhibition of vascular healing and enhancement of inflammatory pathways which ultimately leads to atherosclerosis. Although homing of progenitor cells into bone marrow has been extensively studied, domiciliation of precursor cells into peripheral tissues and differentiation into mature cells are poorly understood so far. Recently, the role of platelets in domiciliation and subsequent differentiation of progenitor cells has been highlighted. Adherent platelets recruit circulating progenitor cells in vitro and in vivo and induce differentiation of the latter into endothelial cells or macrophages and foam cells. Although further studies are needed to describe the mechanisms that lie underneath these observations, it seems that platelet interaction with progenitor cells is an essential step in both vascular regeneration and injury.
Reaction time during semi‐automated kinetic perimetry (SKP) in patients with advanced visual field loss
2008-12-18

Abstract. Purpose: This study aimed to evaluate reaction time (RT) in patients with advanced visual field (VF) loss using semi‐automated kinetic perimetry (SKP). Methods: Seventy‐eight patients with advanced VF loss caused by glaucoma (31) or retinitis pigmentosa (19), homonymous VF loss caused by post‐chiasmal lesions (18) and unilateral anterior ischaemic optic neuropathy (AION) (10) were examined with SKP (Octopus 101 perimeter). One eye in each patient was enrolled. Additionally, VFs in the 10 healthy fellow eyes of the patients with AION were compared with those in the 10 affected eyes. Reaction time was assessed during the SKP session by presenting kinetic stimuli (III4e) with constant angular velocities of 3 °/second moving linearly along so‐called ‘RT vectors’ at four different locations inside the III4e isoptre. Each stimulus presentation was repeated four times in randomized order. Results: The geometric mean RT was 794 ms (95% reference interval [RI] 391–1615 ms) in patients with glaucoma, 702 ms (95% RI 306–1608 ms) in patients with retinitis pigmentosa and 675 ms (95% RI 312–1460 ms) in patients with hemianopia. Increases in RT for every 1 ° of eccentricity were 1%, 0.9% and 0.4%, respectively. The geometric mean RT in the 10 patients with unilateral optic neuropathy was 644 ms in affected eyes and 435 ms in unaffected eyes, reflecting an increase of 51% (95% confidence interval 42–62%). Conclusions: We found substantial inter‐subject variability in RT in patients with advanced VF loss. It is possible to correct the position of the isoptres by assessing individual RT. There were no relevant differences in RT between the disease groups. Reaction time increases with eccentricity. In monocular disease (AION), RT is prolonged, compared with in healthy fellow eyes. However, in clinical routine the RT‐related displacement of isoptres is negligible in the vast majority of cases.
The Fluorinated and Chlorinated Nuclear Localization Sequence of the SV 40 T Antigen
2008-12-18

Nuclear uptake of the simian virus (SV) 40 T antigen is triggered by a specific nuclear localization sequence. However, such a nuclear localization sequence is only poorly taken up by the cytoplasm of cells when administered to the culture medium. Our aim was to improve the cytoplasmic uptake of the SV 40 T antigen nuclear localization sequence. Consequently, we synthesized novel fluorescein isothiocyanate‐labelled conjugates containing the nuclear localization sequences of the SV 40 T antigen and either trichlorobenzoic or trifluorobenzoic acid. Applied at 260 μ m such halogenated NLS conjugates were nuclearly taken up by 75–85% of U373 and LN18 glioma cells and resulted in cell death. Nuclear staining and cell death were also found at lower concentrations (130 and 65 μ m ) of halogenated nuclear localization sequence conjugates. By contrast only a low cellular staining rate and no cell death could be observed after co‐incubation with a trichlorobenzoic acid or trifluorobenzoic acid‐lacking nuclear localization sequence conjugate and free, unbound trichlorobenzoic acid or trifluorobenzoic acid at the high concentration (260 μ m ). Such small non‐radioactive fluorinated and chlorinated nuclear localization sequences may be used as important components for future antiglioma drug development.
ChemInform Abstract: Synthesis of Phthalonitriles Using a Palladium Catalyst.
2008-12-18

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Characteristics of Voluntary Sports Clubs Management: a Sociological Perspective
2008-12-19

Abstract The voluntary sports club constitutes an organization that differs considerably in its structural condition from economic enterprises. The aim of this paper is to discuss the general characteristics of voluntary sports club management. For this purpose, using a sociological management approach, the paper attempts to analyze the organizational structures of sports clubs. The analysis shows the following: the absence of explicit organizational objectives makes it very difficult to validate successful development. The incongruity of power and professional competence, and the ambiguous distribution of tasks hampers well-grounded decision making. Furthermore, recruiting managerial staff from within the club is a major factor that prevents organizational change. Consequently, specific management concepts for voluntary sports clubs need to be developed. In doing so, blindly transferring economic concepts must be avoided in order to ensure that public utility is not jeopardized in the long run.
17β-Estradiol Modulates Apoptosis in Pancreatic β-Cells by Specific Involvement of the Sulfonylurea Receptor (SUR) Isoform SUR1
2008-12-19

Apoptosis of pancreatic beta-cells is an important factor in the pathophysiology of diabetes. Previously, we have shown that the "phytoestrogen" resveratrol can induce beta-cell apoptosis dependent on the expression of sulfonylurea receptor (SUR) 1, the regulatory subunit of pancreatic ATP-sensitive K(+) channels. Here, we investigate whether 17beta-estradiol also influences beta-cell apoptosis in a SUR1-dependent manner. Therefore, islets from wild type or SUR1 knock-out mice, clonal beta-cells, or HEK293 cells expressing different SUR forms were treated with 17beta-estradiol or estrone. Different apoptotic parameters were determined and estrogen binding to SUR was analyzed. In murine islets, 17beta-estradiol treatment resulted in significant apoptotic changes, which in their nature (either apoptotic or anti-apoptotic) were dependent on the age of the animal. These effects were not observed in SUR1 knock-out mice. Furthermore, 17beta-estradiol, which specifically binds to SUR, induced enhanced apoptosis in SUR1-expressing HEK293 cells and clonal beta-cells, whereas apoptosis in recombinant cells expressing SUR2A or SUR2B (cardiac or vascular SUR-isoforms) or sham-transfected control cells was significantly lower. The apoptotic potency of 17beta-estradiol was much higher than that of resveratrol or estrone. SUR1-specific 17beta-estradiol-induced apoptosis was either abolished by the mutation M1289T in transmembrane helix 17 of SUR1 or clearly enhanced by two mutations in nucleotide binding fold 2 (R1379C, R1379L). In conclusion, 17beta-estradiol treatment modulates beta-cell apoptosis under specific involvement of SUR1 in an age-dependent manner. 17beta-Estradiol-induced apoptosis can be influenced by certain SUR1 mutations. These findings may contribute to the understanding of pathophysiological changes in beta-cell mass and could, for instance, provide interesting aspects concerning the etiology of gestational diabetes.
Partial double bond character in chalcogen compounds of stanna-closo-dodecaborate
2008-12-19

The following chalcogen compounds of stanna-closo-dodecaborate were synthesized and characterized: the tetrameric oxide [(O-SnB(11)H(11))(4)](8-) from the reaction with hydrogen peroxide and the sulfide and selenide [S-SnB(11)H(11)](2-), [Se-SnB(11)H(11)](2-) from the reaction with elemental sulfur and selenium, respectively. The stannaborate derivatives were characterized by (119)Sn Mössbauer spectroscopy and single crystal structural analysis. The character of the bond between the tin and group 16 elements was studied extensively by using quantum chemical methods.