bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conformational choices for the stereochemically constrained γ‐amino acid residue gabapentin: Theoretical studies and correlation with experimental results
Authors: Vasudev Prema G. , Chatterjee Sunanda , Ramakrishnan Chandrasekharan , Shamala Narayanaswamy , Balaram Padmanabhan 
Published: April 2009

AbstractGabapentin (1‐aminomethylcyclohexaneacetic acid, Gpn) is an achiral, conformationally constrained γ amino acid residue. A survey of available crystal structures of Gpn peptides reveals that the torsion angles about the CγCβ (θ1) and CβCα (θ2) bonds are overwhelmingly limited to gauche, gauche (g+g+/g−g−) conformations. The Gpn residue forms C7 and C9 hydrogen bonds in which the donor and acceptor atoms come from the flanking peptide units. In combination with α amino acid residues αγ and γα segments can adopt C12 hydrogen bonded structures. The conformational choices available to the Gpn residue have been probed using energy calculations, adopting a grid search strategy. Ramachandran ϕ–ψ maps have been constructed for fixed values of θ1 and θ2, corresponding to the gauche and trans conformations. The sterically allowed and energetically favorable regions of conformational space have been defined and experimental observations compared. C7 and C9 hydrogen bonded conformational families have been identified using a grid search approach in which θ1 and θ2 values are varied over a range of ±10° about ideal values at 1° intervals. The theoretical analysis together with experimental observations for 59 Gpn residues from 35 crystal structures permits definition of the limited range of conformational possibilities at this γ amino acid residue. © 2009 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 92: 426–435, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Colonic ischaemia and intra-abdominal hypertension following open repair of ruptured abdominal aortic aneurysm
Authors: Djavani K , Wanhainen A , Valtysson J , Björck M 
Published: April 2009

Abstract

Background
The aim was to investigate the association between colonic ischaemia and intra-abdominal pressure (IAP) after surgery for ruptured abdominal aortic aneurysm (rAAA).

Methods
Sigmoid colon perfusion was monitored with an intramucosal pH (pHi) tonometer. Patients with a pHi of 7·1 or less were treated for suspected hypovolaemia with intravenous colloids and colonoscopy. IAP was measured every 4 h. Patients with an IAP of 20 mmHg or more had neuromuscular blockade, relaparotomy or both.

Results
A total of 52 consecutive patients had open rAAA repair; 30-day mortality was 27 per cent. Eight patients died shortly after surgery. Fifteen were not monitored for practical reasons; mortality in this group was 33 per cent. IAP and pHi were measured throughout the stay in intensive care in the remaining 29 patients. Monitoring led to volume resuscitation in 25 patients, neuromuscular blockade in 16, colonoscopy in 19 and relaparotomy in two. One patient died in this group. Twenty-three of 29 patients had a pHi of 7·1 or less, of whom 15 had a pHi of 6·9 or less. Sixteen had an IAP of 20 mmHg or more, of whom ten also had a pHi below 6·90. Peak IAP values correlated with the simultaneously measured pHi (r = –0·39, P = 0·003).

Conclusion
Raised IAP is an important mechanism behind colonic hypoperfusion after rAAA repair. Monitoring IAP and timely intervention may improve outcome.
Determination of teniposide in rat plasma by ultra performance liquid chromatography electrospray ionization tandem mass spectrometry after intravenous administration
Authors: Wang Jing , Zhang Yu , Guan Tingting , Lin Xia , Tang Xing , Xu Hui 
Published: April 2009

AbstractA novel, specific and rapid ultra performance liquid chromatography electrospray ionization tandem mass spectrometry method has been developed and validated for determination of teniposide in rat plasma. A one‐step liquid–liquid extraction method was used and the separation was carried out on an Acquity UPLCTM BEH C18 column with gradient elution using a mobile phase composed of acetonitrile and water (containing 0.1% formic acid) at a flow rate of 0.20 mL/min. A triple quadrupole tandem mass spectrometer in multiple‐reaction monitoring mode via an electrospray ionization interface was used for the detection of teniposide. The detection was complete within 3.0 min. A linear calibration curve was obtained over the concentration range 10–10,000 ng/mL for teniposide, with a lower limit of quantification of 10 ng/mL. The intra‐day precision and inter‐day precision (relative standard deviation) were less than 10.23 and 13.09%, respectively. The developed method was applied for the first time to the pharmacokinetic study of teniposide in rats following a single intravenous administration of 4.5 mg/kg teniposide. Copyright © 2009 John Wiley & Sons, Ltd.
Isolation and purification of isoflavonoids from Rhizoma Belamcandae by two‐dimensional preparative high‐performance liquid chromatography with column switch technology
Authors: Jiang Yunyun , Zhao Weiquan , Feng Chao , Zhou Tingting , Fan Guorong , Wu Yutian 
Published: April 2009

AbstractA two‐dimensional column‐switching system without sample loop trapping, where two columns were operated via a six‐port switching valve, was employed in the isolation and purification of five isoflavonoids from Rhizoma Belamcandae: tectoridin, iridin, tectorigenin, irigenin and irisflorentin. The introduction of the six‐port switching value, instead of a sample loop, assured 100% recovery from the first dimension to the second, and the injection volumes of the second dimension were not restricted. Two configurations were tested in this study. In the first mode, only one column was used in the second dimension and two ‘heart‐cutting’ fractions were transported to the same second‐dimensional column. In the second mode, two parallel columns were used in the second dimension and two fractions were transported to the two columns. Between the two configurations, the one with two second dimensional columns had double sample size, better resolution and one more purified compound. Both two‐dimensional configurations consumed less solvent with even greater efficiency and shorter cycle time compared with conventional gradient methods. All of the isoflavonoids were isolated at high purities of greater than 95% with yields of above 82%. Copyright © 2009 John Wiley & Sons, Ltd.
Plasma phospholipid metabolic profiling and biomarkers of rats following radiation exposure based on liquid chromatography–mass spectrometry technique
Authors: Wang Chang , Yang Jun , Nie Jihua 
Published: April 2009

AbstractLipidomics, a prominent area of metabolomics, utilizes novel analytical methodologies to study the extensive classes of lipid molecules, changes in lipid metabolism and lipid‐mediated signaling processes. In this paper, the phospholipid metabolic profiles changes and potential biomarker identification in the rats plasma after γ‐irradiation exposure were investigated by coupling high performance liquid chromatography–mass spectrometry technology to multivariate statistical analysis. Orthogonal partial least‐squares to latent structures discriminate analysis (OPLS‐DA) was used to find the potential plasma phospholipids biomarkers of rats for radiation exposure. According to the corresponding tandem mass spectrometric results, potential biomarkers were identified. After exposure to γ‐rays, phosphatidylethanolamine and phosphatidylserine showed a marked increase, and phosphatidylcholine, sphingomyelin and lysophosphatidylcholine followed the same trend, although their rise was not significant. The results suggested that radiated rats had a phospholipid metabolic abnormality, which could be an alternative way to assess the radiaton exposure. The biomarkers may involve a radiation‐induced apoptosis pathway and represent a promising target for discovery new radioprotective drugs and radiosensitizers. Copyright © 2009 John Wiley & Sons, Ltd.
Simulink‐based implementation of TCSC‐operated single‐phase induction motor as an educational tool
Authors: Alomoush Muwaffaq I. , Albatran Saher A. 
Published: April 2009

AbstractThe article presents a method to achieve a variable capacitance in the auxiliary circuit of single‐phase induction motor (SPIM) using thyristor controlled series compensator (TCSC) which is considered as a controllable variable impedance that can considerably alter impedance of a circuit in which it is inserted to be capacitive or inductive. The TCSC can change its impedance quickly as firing angle is controlled, therefore, it can be utilized as variable capacitor to improve starting torque and enhance running performance of the SPIM. The article also presents an unsophisticated Simulink‐based model for a TCSC‐operated SPIM to be an educational approach that fits different operation conditions of the motor by adopting a very simple fashion. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 514–524, 2011
On MATLAB demonstrations of narrowband Gaussian noise
Authors: Jovanovic Dolecek Gordana , Harris Fred 
Published: April 2009

AbstractA demo program for teaching characteristics of narrowband Gaussian noise (NBGN) by using MATLAB environment is presented in this article. Programs are developed in MATLAB tool makeshow, and users are led step by step through the statistical characteristics of the NBGN including probability density and distribution functions, and the corresponding probability. The evaluation of the software by users is also included. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 598–603, 2011
Simulation and testing of hybrid vehicle function as part of a multidisciplinary training
Authors: Jiménez Felipe , López José María , Sánchez Javier , Cobos Pedro 
Published: April 2009

AbstractThis article approaches a detailed analysis of hybrid vehicles and their components by using a mathematical model programmed in Matlab–Simulink. This model has been developed to enable students to adopt a global approach, tackling aspects of different subjects of Mechanical Engineering studies. The program is also used to supplement practical laboratory sessions. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 604–614, 2011
Over‐expression of SUMO‐1 induces the up‐regulation of heterogeneous nuclear ribonucleoprotein A2/B1 isoform B1 (hnRNP A2/B1 isoform B1) and uracil DNA glycosylase (UDG) in hepG2 cells
Authors: Ma Kit Wan , Au Shannon W. N. , Waye Mary M. Y. 
Published: April 2009

AbstractSumoylation is one of the post‐translational modifications that governs many cellular activities, including subcellular localization targeting, protein‐protein interaction, and transcriptional activity regulation. SUMO E3 ligases are responsible for substrate specificity determination in which PIAS is the largest E3 family that consists of five members in human; they are PIAS1, PIAS3, PIASxα, PIASxβ, and PIASy. Several studies showed that all these PIAS genes are highly expressed in testis but only a few reports have discussed their expression pattern in other tissues. Though liver is a multifunctional organ and one would expect to find regulation of cellular functions by sumoylation, the identified sumoylation substrates are scarce and few of them correlate with liver cancer. In this report, we have found that PIASxα, PIASxβ, and PIASy are highly expressed in liver as well as testis by tissue distribution studies. We thus aimed to identify any SUMO‐1 related proteins in liver cancer cells by two‐dimensional gel electrophoresis and mass spectrometry. Two up‐regulated proteins, heterogeneous nuclear ribonucleoprotein A2/B1 isoform B1 (hnRNP A2/B1 isoform B1) and uracil DNA glycosylase (UDG), have been identified in the EGFP‐SUMO‐1 over‐expressing HepG2 cells. The up‐regulation is suggested to be mediated via changes at the translational level or protection from degradation by western blotting and RT‐PCR. Copyright © 2009 John Wiley & Sons, Ltd.
Low concentration of lipopolysaccharide acts on MC3T3‐E1 osteoblasts and induces proliferation via the COX‐2‐independent NFκB pathway
Authors: Wang Le‐Yu , Wang Hai‐Yi , Ouyang Jun , Yu Lei , Chen Bing , Qin Jian‐Qiang , Qiu Xiao‐Zhong 
Published: April 2009

AbstractThe translocations of lipopolysaccharide (LPS) from the gut and its effects on bone healing are usually of clinical interest during bone fracture. As already widely stuided, Cyclooxygenase‐2 (COX‐2) is a key enzyme for prostaglandin E2 (PGE2) production, which induces the nuclear factor kappa B (NFκB) activation and is beneficial to fracture healing. In order to know their roles in skeletal regeneration, mouse MC3T3‐E1 osteoblasts were treated with NFκB inhibitor BAY 11‐7082 and sc791 (a selective COX‐2 inhibitor), in the presence of LPS. Interestingly, LPS could induce osteoblasts proliferation through increasing NFκB activation and translocation. This induction was not related to COX‐2 expression, suggesting that LPS‐induced NFκB activiation is independent of COX‐2. It is possible that low concentration of LPS can act as a stimulating factor of the NFκB pathway in nonstimulated cells such as osteoblasts. COX‐2 is not necessary for the NFκB pathway during LPS‐induced proliferation of osteoblasts since sc791 had no effects on this induction. These studies provide insight into a potential mechanism by which LPS can affect bone tissue repair in the initial phase of inflammation. Copyright © 2009 John Wiley & Sons, Ltd.
FOIST: Fluid–object interaction subcomputation technique
Authors: Udoewa V. 
Published: April 2009

AbstractOur target is to develop computational techniques for studying aerodynamic interactions between multiple objects. The computational challenge is to predict the dynamic behavior and path of the object, so that separation (the process of objects relatively falling or moving away from each other) is safe and effective. This is a very complex problem because it has an unsteady, 3D nature and requires the solution of complex equations that govern the fluid dynamics (FD) of the object and the aircraft together, with their relative positions changing in time.Large‐scale 3D FD simulations require a high computational cost. Not only must one solve the time‐dependent Navier–Stokes equations governing the fluid flow, but also one must handle the equations of motion of the object as well as the treatment of the moving domain usually treated as a type of pseudo‐solid. These costs include mesh update methods, distortion‐limiting techniques, and remeshing and projection tactics. To save computational costs, point force calculations have been performed in the past. This paper presents a hybrid between full mesh‐moving simulations and the point force calculation. This mesh‐moving alternative is called FOIST: fluid–object subcomputation interaction technique. Copyright © 2009 John Wiley & Sons, Ltd.
Neues DGfM‐Merkblatt “Brandschutz mit Mauerwerk”
Authors: Hahn Christiane , Rast Ronald 
Published: April 2009

AbstractEs bereitet immer wieder Schwierigkeiten, aus den bauordnungsrechtlichen Anforderungen diejenigen herauszufiltern, die auf das konkrete, zu planende oder zu bauende Gebäude zutreffen. Die Musterbauordnung 2002 [1] hat eine neue Klassifizierung der Gebäude auf der Grundlage der Kriterien Brandrisikos, Brandauswirkungen und Rettungs‐ und Bekämpfungsmöglichkeiten der Feuerwehr gebracht [2]. Da Bauordnungsrecht Ländersache ist, trifft der Planer oder bauausführende auf z. T. unterschiedliche Anforderungen in den jeweiligen Bundesländern, was die Sache noch zusätzlich erschwert. Die Umsetzung der Anforderungen geschieht mit Hilfe der genormten klassifizierten Baustoffe und Bauteile bzw. über allgemeine bauaufsichtliche Zulassungen bzw. allgemeine bauaufsichtliche Prüfzeugnisse oder gar eine Zustimmung im Einzelfall. Um hierbei eine Hilfestellung zu geben, hat die Deutsche Gesellschaft für Mauerwerksbau die Autorin beauftragt, ein Merkblatt zu erarbeiten, das die Anwendung von Mauerwerk bei zu erfüllenden Brandschutzanforderungen erleichtern soll.In dem Beitrag werden kurz die bauordnungsrechtlichen Anforderungen und die grundlegende Klassifizierung der Baustoffe und Bauteile erläutert und der vorgesehene Inhalt des DGfM‐Merkblattes vorgestellt.
Brandschutz mit Mauerwerk auf der Basis von DIN 4102‐4 in Verbindung mit DIN 4102‐22 – Bisherige Entwicklung, Stand und Ausblick
Authors: Hahn Christiane 
Published: April 2009

AbstractDer bauordnungsrechtlich erforderliche Nachweis der Feuerwiderstandsdauer tragender Bauteile erfolgte bisher auf der Basis der in der DIN 4102‐4 ([1], [2]) klassifizierten Baustoffe und Bauteile. Die Vorgehensweise war einfach und erwies sich als äußerst praktikabel. DIN 4102‐4 enthält nicht nur tragende Bauteile, sondern auch zahlreiche Angaben zu nichttragenden Bauteilen und Ausbaukonstruktionen.Mit der Umstellung auf das semiprobalistische Sicherheitskonzept machte sich die Anwendungsnorm DIN 4102‐22 [3] erforderlich, die die Beziehung zu der bisherigen Klassifizierung unter Beachtung der Generation der neuen Bemessungsnormen sicher zu stellen hatte.Der Beitrag gibt einen Einblick in die Entwicklung und die derzeitige Normungssituation bei der Brandbemessung im Mauerwerksbau. Es wird dabei auf die Unterschiede zwischen altem und neuem Sicherheitskonzept eingegangen. Die 2009 zu erwartenden Änderungen zu DIN 4102‐4 und ‐22 werden kurz vorgestellt.
Brandschutz mit Ziegelmauerwerk im Wohnungsbau
Authors: Meyer Udo , Nause Peter 
Published: April 2009

AbstractZiegelmauerwerk hat sich seit Jahrhunderten auch aus brandschutztechnischer Sicht bewährt. Ziegel sind nicht brennbar und leisten keinen Beitrag zum Brand. Für alle Anforderungen stehen Ziegel‐Produkte zur Verfügung, mit denen in den statisch ohnehin erforderlichen Wanddicken die Anforderungen der Landesbauordnungen erfüllt werden. Im folgenden Beitrag werden die wichtigsten Anforderungen und die Leistungsfähigkeit von Ziegelmauerwerk im Hinblick auf den Brandschutz in den verschiedenen Anwendungsbereichen des Wohnungsbaus dargestellt.
Die neuen EU‐Normen zur Klassifizierung und Bemessung von Porenbetonbauteilen unter Brandeinwirkung
Authors: Flassenberg Georg 
Published: April 2009

AbstractDie Anforderungen hinsichtlich des Brandschutzes von Gebäuden sind in den Vorschriften der Landesbauordnungen (vgl. [1]) und der auf ihrer Grundlage erlassenen Sonderbauverordnungen und Verwaltungsvorschriften geregelt, was auch zukünftig so bleiben wird. Die deutsche brandschutztechnische Klassifizierung von Baustoffen und Bauteilen erfolgte bisher nach DIN 4102‐4 ([2] bis [5]). Darüber hinaus ist nunmehr auch das in den vergangenen Jahren erarbeitete einheitliche europäische Klassifizierungskonzept für den Bereich Brandschutz fertiggestellt und kann, wie im Folgenden dargestellt, angewendet werden (vgl. Anlage 0.1 der BauregellisteA Teil 1 [6]).Die Brandschutzanforderungen lassen sich sowohl nach deutscher als auch nach europäischer Klassifizierung mit Porenbetonmauerwerk zuverlässig und ohne Schwierigkeiten erfüllen.
Wohnungsbedarf in Deutschland bis zum Jahr 2025
Authors: Günther Matthias 
Published: April 2009

AbstractAusgangpunkt dieses Beitrages ist eine Studie, die das ISP Eduard‐Pestel‐Institut für Systemforschung e. V. im Auftrag des Bundesverbandes Deutscher Baustoff‐Fachhandel e. V. (BDB), des Bundesverbandes Freier Immobilien‐ und Wohnungsunternehmen e. V. (BFW) und der Deutschen Gesellschaft für Mauerwerksbau e. V. (DGfM) erstellt hat. Ziel der Untersuchung war die Ermittlung des künftigen Wohnungsbedarfs in Deutschland auf der Ebene der Kreise und kreisfreien Städte.
Toward defining the phosphoproteome of Xenopus laevis embryos
Authors: McGivern Jered V. , Swaney Danielle L. , Coon Joshua J. , Sheets Michael D. 
Published: April 2009

AbstractPhosphorylation is universally used for controlling protein function, but knowledge of the phosphoproteome in vertebrate embryos has been limited. However, recent technical advances make it possible to define an organism's phosphoproteome at a more comprehensive level. Xenopus laevis offers established advantages for analyzing the regulation of protein function by phosphorylation. Functionally unbiased, comprehensive information about the Xenopus phosphoproteome would provide a powerful guide for future studies of phosphorylation in a developmental context. To this end, we performed a phosphoproteomic analysis of Xenopus oocytes, eggs, and embryos using recently developed mass spectrometry methods. We identified 1,441 phosphorylation sites present on 654 different Xenopus proteins, including hundreds of previously unknown phosphorylation sites. This approach identified several phosphorylation sites described in the literature and/or evolutionarily conserved in other organisms, validating the data's quality. These data will serve as a powerful resource for the exploration of phosphorylation and protein function within a developmental context. Developmental Dynamics 238:1433–1443, 2009. © 2009 Wiley‐Liss, Inc.
The shroom family proteins play broad roles in the morphogenesis of thickened epithelial sheets
Authors: Lee Chanjae , Le Minh‐Phuong , Wallingford John B. 
Published: April 2009

AbstractThickened epithelial sheets are found in a wide variety of organ systems and the mechanisms governing their morphogenesis remain poorly defined. We show here, through expression patterns and functional studies, that Shroom family proteins are broadly involved in generating thickened epithelial sheets. Through in situ hybridization, we report the temporal and spatial expression patterns of the four Shroom family members during early Xenopus development, from oocytes to tadpole stage embryos. Further, we show that Shroom1 and 2 mRNAs are maternally expressed, while Shroom3 and Shroom4 are zygotic transcripts. In addition, maternal Shroom1 and 2 mRNAs localize in the animal hemisphere of the Xenopus egg and early blastula. During later development, all four Shroom family proteins are broadly expressed in developing epithelial organs, and the epithelial cells that express Shrooms are elongated. Moreover, we show that ectopic expression of Shroom2, like Shroom3, is able to increase cell height and that loss of Shroom2 function results in a failure of cell elongation in the neural epithelium. Together, these data suggest that Shroom family proteins play an important role in the morphogenesis of several different epithelial tissues during development. Developmental Dynamics 238:1480–1491, 2009. © 2009 Wiley‐Liss, Inc.
A novel role for the chemokine receptor Cxcr4 in kidney morphogenesis: An in vitro study
Authors: Ueland Joseph , Yuan Amy , Marlier Arnaud , Gallagher Anna Rachel , Karihaloo Anil 
Published: April 2009

AbstractThe CXCR4 chemokine receptor is involved in hematopoietic stem cell homing, neuronal development, and angiogenesis. We show a significant new role for this receptor in epithelial patterning and renal morphogenesis. This receptor is expressed in the ureteric bud (UB) and the metanephric mesenchyme (MM). Stimulation of Cxcr4 in renal tubular cells leads to activation of multiple signaling pathways and tubulogenesis and cell migration. Knocking down of this receptor in tubular cells leads to cyst formation. Inactivation of this receptor in embryonic kidney explants results in impaired UB branching and mesenchymal tubulogenesis. The data presented here point to its importance in the process of mesenchymal‐to‐epithelial transitioning (MET), a crucial developmental process in the embryonic kidney. A number of genes important for normal tubulogenesis and MET are decreased upon CXCR4 inactivation. Developmental Dynamics 238:1083–1091, 2009. © 2009 Wiley‐Liss, Inc.