bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of sinomenine on the in vitro intestinal epithelial transport of selected compounds
Authors: Lu Zhilei , Chen Weiyang , Viljoen Alvaro , Hamman Josias H. 
Published: July 2009

AbstractHerbal products can interfere with allopathic medicinal treatment through pharmacokinetic and pharmacodynamic interactions. Although pharmacokinetic interactions that alter drug absorption may cause variable and unsatisfactory drug bioavailability, a drug absorption enhancement effect of a herb may be used to ensure sufficient absorption of poorly absorbable drugs. The effect of the hydrochloride salt of sinomenine, an alkaloid obtained from the plant Sinomenium acutum, on the transepithelial electrical resistance and transport of different compounds (including cimetidine, vitamin C, rutin, luteolin and insulin) across Caco‐2 epithelial cell monolayers was investigated in this study. Sinomenine HCl induced a concentration dependent lowering effect on the transepithelial electrical resistance of Caco‐2 cell monolayers, which was completely reversible. Sinomenine HCl significantly increased the transport of all the test compounds in the apical‐to‐basolateral direction compared with the control group and decreased the transport of cimetidine, a P‐glycoprotein substrate, in the basolateral‐to‐apical direction. From these results it can be concluded that sinomenine HCl increases drug absorption across the intestinal epithelium by means of one or more mechanisms including a transient opening of the tight junctions (as indicated by a reduction in transepithelial electrical resistance) to allow for paracellular transport and/or inhibition of active drug efflux transport (as indicated by inhibition of basolateral‐to‐apical transport of cimetidine). Copyright © 2009 John Wiley & Sons, Ltd.
Cytotoxic guaianolide from Anthemis segetalis (Asteraceae)
Authors: Vučković Ivan , Vujisić Ljubodrag , Stešević Danijela , Radulović Siniša , Lazić Milan , Milosavljević Slobodan 
Published: July 2009

AbstractTwo epimeric guaianolides were isolated from the aerial parts of Anthemis segetalis. These compounds have not been detected in any Anthemis species so far. One of them was tested for cytotoxicity against human cervical cancer (HeLa) and murine melanoma (B16) cell lines showing appreciable activity. Copyright © 2009 John Wiley & Sons, Ltd.
Hypoglycemic effect of aqueous extract of seabuckthorn (Hippophae rhamnoides L.) seed residues in streptozotocin‐induced diabetic rats
Authors: Zhang Wen , Zhao Jingjing , Wang Jiesi , Pang Xiufeng , Zhuang Xiuyuan , Zhu Xinglei , Qu Weijing 
Published: July 2009

AbstractAn extract of seabuckthorn (Hippophae rhamnoides L.) seed residues has been shown to possess hypoglycemic and hypolipidemic properties in normal mice. The present study investigated the effects of an aqueous extract of seabuckthorn seed residues (ASSR) on serum glucose, lipid profiles and antioxidant parameters in streptozotocin‐induced diabetic rats. Male Sprague‐Dawley rats were divided into four groups: a normal control group; diabetic control group; diabetic groups supplemented with 5 mg/kg body weight glibenclamide (reference drug) and 400 mg/kg body weight ASSR. Diabetes in rats was induced by intraperitoneal injection of streptozotocin (45 mg/kg body weight). Vehicle (distilled water), glibenclamide and ASSR were administered orally to normal and diabetic rats once a day lasting for 4 weeks. The data showed that administration of ASSR significantly lowered the serum glucose, triglyceride and nitric oxide levels in diabetic rats. Moreover, ASSR treatment also increased serum superoxide dismutase activity and glutathione level markedly. These results show that ASSR has hypoglycemic, hypotriglyceridemic and antioxidant effects in streptozotocin‐induced diabetic rats, suggesting that ASSR supplementation can be useful in preventing diabetic complications associated with hyperlipidemia and oxidative stress. Copyright © 2009 John Wiley & Sons, Ltd.
Hypericum perforatum L. (St John's wort) extract Ze 117 inhibits dopamine re‐uptake in rat striatal brain slices. An implication for use in smoking cessation treatment?
Authors: Ruedeberg C. , Wiesmann U. N. , Brattstroem A. , Honegger U. E. 
Published: July 2009

AbstractClassic synthetic antidepressant drugs, as well as St John's wort extract (SJW), directly inhibit the re‐uptake of norepinephrine (NE) and/or serotonin (5‐HT) into pre‐synaptic axons. With chronic treatment they induce adaptive changes in a number of neurotransmitter receptors in synaptic membranes. The immediate effects of SJW Ze 117, an extract low in hyperforin content, on the specific dopamine (DA) uptake were studied in rat striatal brain slices and compared with the effects on NE and 5‐HT uptake in rat cortical brain slices.Specific DA uptake was inhibited in a dose dependent manner. In contrast to the findings in synaptosomal preparations published so far, the extract showed different inhibitory potencies for the respective transporters. The potencies for the uptake inhibition of NA, DA and 5‐HT were 30, 7 and 1, respectively. The results indicate that the SJW Ze 117 extract interferes in three ways with the individual uptakes of the relevant neurotransmitters that are considered to be causal in the development of depression.This observation, the concomitant and potent inhibition of DA re‐uptake by SJW extract, may additionally provide a rationale for the treatment of nicotine or drug addiction with SJW. Copyright © 2009 John Wiley & Sons, Ltd.
Screening for acetylcholinesterase inhibitory activity in plant extracts from Argentina
Authors: Carpinella María C. , Andrione Diego G. , Ruiz Gustavo , Palacios Sara M. 
Published: July 2009

AbstractPlants are a potential source of bioactive compounds and offer a promising strategy for the treatment of neurological disorders such as Alzheimer's disease.The inhibitory effect of 73 native and naturalized plants collected from the central region of Argentina on acetylcholinesterase (AChE) was tested using microplate and TLC assays after solvent fractionation of complete ethanol extracts obtained from the plants.Organic fractions obtained from extracts ofAchyrocline tomentosa(Asteraceae),Eupatorium viscidum(Asteraceae),Ruprechtia apetala(Polygonaceae)Trichocline reptans(Asteraceae) andZanthoxylum coco(Rutaceae) presented strong inhibition of AChE (higher than 80%) at 1 mg/mL, withR. apetalaandT. reptansbeing the most potent, showing complete inhibition of the enzyme. Their IC50values were 0.0779 and 0.1118 mg/mL, respectively. Aqueous fractions did not show any inhibitory activity on the enzyme. These results suggest that the most effective extracts deserve further investigation with the aim of obtaining new molecules for the treatment of neurodegenerative disorders. Copyright © 2009 John Wiley & Sons, Ltd.
Screening of Kit inhibitors: suppression of Kit signaling and melanogenesis by emodin
Authors: Lee Seong Jin , Jeong Daeyoung , Park Woo‐Kyu , Kong Jae Yang , Choi Gildon , Kim Hojeong , Kang Sangjin , Cho Heeyeong 
Published: July 2009

AbstractIn search of novel antipigmentation agents, a set of 3,840 compounds with natural‐like synthetic or natural origin were screened against Kit (stem cell factor receptor). Emodin from the seed of Cassia tora and baicalin from Scutellariae radix showed potent inhibitory effects (IC50 = 4.9 and 9.0 mm, respectively) on the phosphorylation of Kit. Emodin also blocked other receptor tyrosine kinase activities, such as epithelial growth factor receptor (EGFR), vascular endothelial growth factor receptor 2 (VEGFR‐2), fibroblast growth factor receptor 1 (FGFR‐1), platelet‐derived growth factor receptor b (PDGFR‐b). In contrast to emodin, aloe‐emodin did not inhibit Kit activity at all. Emodin also blocked the cellular kinase activities of Kit and its down‐stream p44/42 mitogen activated protein kinase (MAPK) in MO7e cells and human primary melanocytes. Emodin strongly suppressed the melanin synthesis triggered by stem cell factor (SCF) treatment. Also, emodin showed almost no toxicity up to 10 mm on cultured melanocytes as reported previously by other researchers. The results indicate that emodin is a good candidate for the development of antipigmentation agents since it can radically block the differentiation and proliferation of pigment cells by reducing Kit signaling. Copyright © 2009 John Wiley & Sons, Ltd.
Ice and water content of stratiform mixed‐phase cloud
Authors: Vidaurre German , Hallett John 
Published: July 2009

AbstractSpatial characterization and probability distribution of particles in stratiform mixed‐phase clouds in the temperature range 5 to −45 °C were investigated based on 81 hours of flight on the NCAR C‐130 during the Alliance Icing Research Study II. Cloud particles were video‐recorded impacting on the optical window of a cloudscope, and Liquid Water Content (LWC) and Ice Water Content (IWC) derived from measurements of the power to evaporate particles of different size, shape and density collected by the T probe constant temperature sensors. Data were recorded at 1 Hz for a resolution of 130 m. Transitions between liquid, glaciated and mixed‐phase regions were sharp; frequent supercooled liquid regions lasted less than 2 seconds (<260 m), while less frequent mixed‐phase and glaciated regions persisted between 2 and 300 seconds (0.26 to 39 km) along the aircraft track. LWC, IWC and Total Water Content (TWC) were measured in concentrations up to 1.25, 0.45 and 1.25 g m−3 with an uncertainty of ∼0.02 g m−3. The IWC/TWC ratio showed two maxima at mostly liquid (<0.1) and mostly ice (>0.9); mixed‐phase corresponded to about 40% of the measurements. The large T probe showed mixed‐phase clouds with ice fraction less than half at temperatures below −20 °C, while the small T probe measured higher ice proportion, suggesting that ice was present in the form of preferentially collected small particles. At high temperatures (>−15 °C) ice and water were measured in concentrations up to 0.2 and 0.6 g m−3 respectively; at temperatures below −20 °C they were both measured in concentrations up to 0.3 g m−3. Copyright © 2009 Royal Meteorological Society
The characteristics of Hessian singular vectors using an advanced data assimilation scheme
Authors: Lawrence A. R. , Leutbecher M. , Palmer T. N. 
Published: July 2009

AbstractInitial condition uncertainty is a significant source of forecast error in numerical weather prediction. Singular vectors of the tangent linear propagator can identify directions in phase‐space where initial errors are likely to make the largest contribution to forecast‐error variance. The physical characteristics of these singular vectors depend on the choice of initial‐time metric used to represent analysis‐error covariances: the total‐energy norm serves as a proxy to the analysis‐error covariance matrix, whereas the Hessian of the cost function of a 4D‐Var assimilation scheme represents a more sophisticated estimate of the analysis‐error covariances, consistent with observation and background‐error covariances used in the 4D‐Var scheme.This study examines and compares the structure of singular vectors computed with the European Centre for Medium‐Range Weather Forecasts (ECMWF) Integrated Forecasting System using these two types of initial metrics. Unlike earlier studies that use background errors derived from lagged forecast differences (the NMC method), the background‐error covariance matrix in the Hessian metric is based on statistics from an ensemble of 4D‐Vars using perturbed observations, which produces tighter correlations of background‐error statistics than in previous formulations. In light of these new background‐error statistics, this article re‐examines the properties of Hessian singular vectors (and their relationship to total‐energy singular vectors) using cases from different periods between 2003 and 2005. Energy profiles and wavenumber spectra reveal that the total‐energy singular vectors are similar to Hessian singular vectors that use all observation types in the operational 4D‐Var assimilation. This is in contrast to the structure of Hessian singular vectors without observations. Increasing the observation density tends to reduce the spatial scale of the Hessian singular vectors. Copyright © 2009 Royal Meteorological Society
Vom Entwurf zur Umsetzung der Stahlkonstruktionen für das Bauwerk Neue Mitte Lehen in Salzburg
Authors: Olipitz Michael , Holzleithner Regina 
Published: July 2009

AbstractDer neu errichtete, multifunktionale Kommunalbau Neue Mitte Lehen ist ein Gebäudekomplex mit Signalwirkung für die gesamte Stadt Salzburg und trägt wesentlich zur Belebung dieses Stadtteiles bei. Die Gebäudeform mit den weit auskragenden Gebäudeteilen Bibliotheksgeschoss und Panoramabar erfordert den Einsatz hochtechnologischer Werkstoffe, wie sie der Baustoff Stahl bestens erfüllen kann. Der Entwicklungsprozess vom Entwurfsgedanken bis zur Umsetzung erfordert ein Planungsteam, das die Herausforderungen besonders in der Phase der Umsetzung bewältigen kann. Im folgenden Aufsatz sind die Aspekte der Stahlkonstruktion vom Entwurf bis zur Montage beschrieben. Immer wo die Gewerke des Beton‐ und Stahlbaus abgestimmt aufeinander arbeiten, ist auf die Schnittstellenproblematik zu achten. Bei diesem Bauvorhaben wurde diese Aufgabe durch die Beteiligten vorbildlich gelöst.From the design up to the realization of the steel constructions for the building Neue Mitte Lehen in Salzburg.Salzburg's newest landmark, the recently completed public building Neue Mitte Lehen, accounts with its utilizations for public life within the quarter. The form with its cantilevering parts makes the use of demanding materials like steel necessary. The design process from first sketches to construction requires a team that masters the challenges especially during the building process. The following text describes aspects of the steel construction from design to erection. Special attendance must be paid to the coordination of the crafts of concrete and steel construction. However this task was perfectly solved within this building project.
Netzgenerierung von Netzwerkbogenbrücken
Authors: Schanack Frank , Brunn Benjamin 
Published: July 2009

AbstractNachdem der Netzwerkbogen über Jahrzehnte nahezu unbeachtet blieb, bildet er heute einen immer beliebteren Bestandteil des Brückenbaurepertoires. Seine statischen Vorteile überzeugen mehr und mehr Brückenbauverwaltungen, so dass in aller Welt zahlreiche neue Netzwerkbogenbrücken entstehen. Umso interessanter werden Hinweise für einen einfachen, raschen und nahezu optimalen Vorentwurf, gerade für “Einsteiger” auf dem Gebiet. Die größte Schwierigkeit beim Entwurf ist die Hängeranordnung, die durch Variablen wie Anzahl der Hängersets, Anzahl der Hänger pro Set sowie Neigungswinkel und Position jedes Hängers beschrieben wird. Anstatt der sehr aufwendigen Bestimmung von Lage und Neigung jedes einzelnen Hängers empfiehlt sich die Verwendung von Generierungsvorschriften für den Entwurf des gesamten Hängernetzes. Die gängigsten Generierungsverfahren Rautennetz, konstante Winkeländerung, konstanter Abstand sowie radiale Hängeranordnung werden erläutert und beurteilt. Letztendlich kristallisiert sich die radiale Hängeranordnung als eine Methode heraus, die auf sehr einfache und schnelle Art und Weise zu einer statisch sehr vorteilhaften Hängeranordnung führt.Generation of network arch hanger arrangements.After the network arch remained almost completely unnoticed for decades, it now constitutes an increasingly popular element of today's bridge construction repertory. Its structural advantages convince more and more bridge authorities, so that numerous new network arches are built all over the world. This circumstance calls for straight‐forward and quick ways to nearly optimal preliminary designs, especially for engineers who are new to this type of bridge. The biggest design challenge is the hanger arrangement that depends on the number of hanger sets, number of hangers per set as well as the hanger slope and hanger position. Instead of determining the geometry of each hanger individually, it is recommended to use general generation methods. The most common generation methods rhombus net, constant angle change, constant distance as well as the radial arrangement are discussed and evaluated. Ultimately, the radial arrangement turns out to be a very easy and fast method to obtain structurally very advantageous hanger arrangements.
Die Erhöhung des Nutzerkomforts von Fußgängerbrücken mit Massendämpfern am Beispiel des August‐Wilhelm‐Stegs in Oranienburg
Authors: Kuhlmann Wolfram , Butz Christiane 
Published: July 2009

AbstractAufgrund ihrer schlanken Bauweise gelten viele Fußgängerbrücken bei personeninduzierten Belastungen als schwingungsanfällig. Die eventuelle Ausstattung einer Brücke mit zusätzlichen Dämpfungsmaßnahmen sollte bereits in der Planungsphase berücksichtigt werden, damit bei Gewissheit, dass Maßnahmen notwendig sind, die Fertigstellung und Eröffnung der Brücke nicht verzögert wird.Im vorliegenden Beitrag wird am Beispiel des August‐Wilhelm‐Stegs in Oranienburg das Vorgehen zwischen Erkennen einer möglichen Schwingungsanfälligkeit, Prüfung der Erforderlichkeit schwingungsdämpfender Maßnahmen, Auslegung und Einbau sowie Überprüfung der Wirksamkeit erläutert. Dabei werden insbesondere die praktischen Aspekte bei der Auslegung der Massendämpfer erläutert.The increasing comfort of footbridges with mass dampers is exemplary shown with the August‐Wilhelm‐Steg in Oranienburg, Germany.Many footbridges are susceptible to pedestrian induced vibrations due to their slender design. Hence, an equipment with additional damping devices on demand should be considered already in the preliminary design phase to avoid unnecessary delays of the erection and opening, if the damping devices are required.In this article the procedure of identifying a potential vibration susceptibility, checking the necessity of damping devices, design and installation as well as checking the working efficiency of them are explained using the example of the August‐Wilhelm‐Steg in Oranienburg. Particular emphasis is laid on the practical aspects when designing tuned mass dampers.
Ein elasto‐plastisches Materialmodell zur realistischen Berechnung der Verformungen mechanisch überhöhter Stahl‐ und Verbundträger
Authors: Böhme Frank , Nelke Harald , Lange Jörg 
Published: July 2009

AbstractZur anteiligen Kompensation der Verformungen von Stahl‐ und Verbundträgern werden diese häufig überhöht eingebaut. Wird die Überhöhung durch eine mechanische Beanspruchung (Boxen) aufgebracht, so besitzt der Stahlträger bereits im Einbauzustand plastische Dehnungen. Wie von Grages in [3] gezeigt, führt dies bei der Rückbelastung zu einer Abnahme der Steifigkeit. Dieses Phänomen ist auch als Bauschinger‐Effekt [2] bekannt und kann bei praktischen Verformungsberechnungen zu einer Unterschätzung der tatsächlich auftretenden Deformationen führen. In dem aktuellen Aufsatz wird ein ratenunabhängiges elasto‐plastisches Materialmodell mit linearer und nichtlinearer isotroper sowie nichtlinearer kinematischer Verfestigung vorgestellt, welches eine realistische Abschätzung der Verformungen erlaubt. Das gezeigte Materialmodell ist durch die geringe Anzahl an Eingangsparametern sehr einfach anwendbar. Eine gezielte Anpassung der einzelnen Parameter wird in anschaulicher Form dargestellt. Die Qualität des Modells wird anhand der Nachrechnung von in [3] durchgeführten Versuchen überprüft.An elasto‐plastic material model for realistic calculation of the deformations of mechanical cambered steel‐ and composite girders.Steel and composite girders are often cambered before they are embedded into structures to compensate deflections. In case of a mechanical pre‐deformation via a hydraulic press the steel girder contains plastic strains before assembly. As shown by Grages [3] this leads to a reduction of stiffness and strength during reverse loading. This phenomenon is also known as the Bauschinger‐Effect [2] and may lead to an underestimation of the real deformation during a structural analysis. In this paper a rate‐independent elastoplastic material model with linear and nonlinear isotropic as well as nonlinear kinematic hardening is introduced which allows a realistic estimation of deformations. The material model presented can be easily applied due to its low number of parameters. A straightforward algorithm to adjust the single parameters is described. The quality of the model is verified by a recalculation of experimental data from [3].
Physicochemical Properties of Non‐thermally Cross‐linked Corn Starch with Phosphorus Oxychloride using Ultra High Pressure (UHP)
Authors: Hwang Duck‐Ki , Kim Byung‐Yong , Baik Moo‐Yeol 
Published: July 2009

AbstractCorn starch (20%, w/w) was non‐thermally and conventionally cross‐linked with phosphorus oxychloride (POCl3; 0.01, 0.05, or 0.1%, based on dry weight of starch) at 400 MPa for 5, 15 and 30 min and at 45°C for 2 h, respectively. Swelling power and solubility of both non‐thermally and conventionally cross‐linked corn starches were relatively lower than those of native corn starch. The pressure holding time did not affect the solubility and swelling power of non‐thermally cross‐linked corn starches. X‐ray diffraction patterns and relative crystallinity were not significantly altered by both conventional and non‐thermal cross‐linking. DSC thermal characteristics of both non‐thermally and conventionally cross‐linked corn starches were not significantly changed indicating that the double helical structure of amylopectin was not influenced by both conventional and non‐thermal cross‐linking reactions. Both non‐thermal and conventional cross‐linking greatly affected the Rapid Visco Analyser (RVA) pasting properties, such as increase in pasting temperature and decrease in peak viscosity compared to native starch. This result suggests that in case of cross‐linking using POCl3, both non‐thermal and conventional methods result in similar physicochemical properties and non‐thermal cross‐linking with POCl3 can reduce the reaction time from 2 h to 15 min. This work shows the potential and possibility of non‐thermal starch modification and provides the basic and scientific information on the physicochemical properties of non‐thermally cross‐linked corn starches with phosphorus oxychloride using UHP.
Determination of Optimum Conditions for Enzymatic Debranching of Cassava Starch and Synthesis of Resistant Starch Type III using Central Composite Rotatable Design
Authors: Mutungi Christopher , Onyango Calvin , Jaros Doris , Henle Thomas , Rohm Harald 
Published: July 2009

AbstractCassava starch was debranched by treatment with isoamylase and pullulanase and the yield of resistant starch type III (RS III) optimized with respect to starch solids concentration (7.5‐15%, w/v), incubation time (8‐24 h) and enzyme concentration using central composite rotatable design. Higher concentrations of pullulanase (10‐35 U/g starch) compared to isoamylase (30–90 mU/g starch) were required to give a similar degree of starch hydrolysis within the experimental domain. A clear debranching end‐point was identifiable by following the reducing value, blue value and β‐hydrolysis limit of cassava starches debranched using isoamylase. It was difficult to define a debranching endpoint of pullulanase treatment by these parameters due to contaminating α‐D‐(1→4) activity. The yield of RS III was significantly higher in isoamylolysates and increased steadily with increasing degree of hydrolysis to peak at 57.3%. Purification of the debranched material further increased the RS III yield to 64.1%. Prolonged (24 h) hydrolysis of cassava starch with high concentration of pullulanase (35 U/g) gave lower RS III contents in the purified (34.2%) and unpurified (36.2%) hydrolysates compared to 49.5 and 62.4%, respectively, at moderate pullulanase concentration (22.5 U/g) and incubation time (16 h).