bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enhanced gene expression through temperature profile‐induced variations in molecular architecture of thermoresponsive polymer vectors
Authors: Lavigne Matthieu D. , Pennadam Sivanand S. , Ellis James , Yates Laura L. , Alexander Cameron , Górecki Dariusz C. 
Published: December 2006

AbstractBackgroundSuccessful non‐viral gene targeting requires vectors to meet two conflicting needs—strong binding to protect the genetic material during transit and weak binding at the target site to enable release. Responsive polymers could fulfil such requirements through the switching of states, e.g. the chain‐extended coil to chain‐collapsed globule phase transition that occurs at a lower critical solution temperature (LCST), in order to transport nucleic acid in one polymer state and release it in another.MethodsThe ability of new synthetic polycations based on poly(ethylenei‐ mine) (PEI) with grafted neutral responsive poly(N‐isopropylacrylamide) (PNIPAm) chains to condense DNA into particles with architectures varying according to graft polymer LCST was assessed using a combination of fluorescence spectroscopy, dynamic light scattering (DLS), zeta sizing, gel retardation and atomic force microscopy studies. Transfection assays were conducted under experimental conditions wherein the polymer components were able to cycle across their LCST.ResultsTwo PEI‐PNIPAm conjugate polymers with different LCSTs displayed coil‐globule transitions when complexed to plasmid DNA, leading to variations in molecular architecture as shown by changes in emission maxima of an environment‐sensitive fluorophore attached to the PNIPAm chains. Gel retardation assays demonstrated differences in electrophoretic mobilities of polymer‐DNA complexes with temperatures below and above polymer LCSTs. Atomic force micrographs showed changes in the structures of polymer‐DNA complexes for a polymer undergoing a phase transition around body temperature but not for the polymer with LCST outside this range. Transfection experiments in C2C12 and COS‐7 cells demonstrated that the highest expression of transgene occurred in an assay that involved a ‘cold‐shock’ below polymer LCST during transfection.ConclusionsDesigned changes in thermoresponsive polycation vector configuration via temperature‐induced phase transitions enhanced transgene expression. The results indicate that changes in molecular architecture induced by a carefully chosen stimulus during intracellular trafficking can be used to enhance gene delivery. Copyright © 2006 John Wiley & Sons, Ltd.
The nutritive value of egg by‐products and their potential bactericidal activity: in vitro and in vivo studies
Authors: Schmidt Lisa D , Blank Gregory , Boros Danuta , Slominski Bogdan A 
Published: December 2006

AbstractTechnical‐grade egg albumen (TA) and whole egg (WE) by‐products are produced in substantial quantities by egg‐breaking facilities across North America. TA and WE products are recovered during processing but are not approved for human consumption. Both products are known to be rich in fat, maternal antibodies, protein and lysozyme, a bactericidal enzyme. The objective of this research was to explore the potential for egg by‐products to be used as a valuable protein, energy and bactericidal supplement in animal nutrition. To improve the nutritive value of TA and WE, spray‐dried samples were heat treated at various temperatures and their digestible protein content was determined in vitro using a pepsin/pancreatin digestion/dialysis system. In addition, enhancement of lysozyme activity towards Gram‐negative bacteria (GNB) by heat or irradiation was examined. Optimal protein digestibility for TA averaged 80% following heat treatment at 105–110 °C for 10 min. In contrast, protein digestibility of spray‐dried TA was only 55%. Heat treatment (100–122 °C) of spray‐dried WE or hot room storage of spray‐dried TA and WE products at 70 °C for up to 14 days had a minimal effect on protein digestibility in vitro. Heat treatment or γ‐irradiation of lysozyme for at least 20 min at 80 °C or 0.5 kGy, respectively, increased antimicrobial activity towards GNB. When compared with either the heat or radiation control treatments, reductions in Escherichia coli and Salmonella enterica serovar Typhimurium populations increased by at least 1 and 0.5 log10, respectively. In contrast, the effect of irradiation (2 kGy) on the antimicrobial activity of spray‐dried TA was less pronounced. In a feeding trial, rats fed spray‐dried TA and spray‐dried TA subjected to either radiation (1.8 kGy) or heat (80 °C, 20 min) treatment exhibited a body weight gain and protein utilisation equal to or higher than the control (casein diet). In contrast, feeding spray‐dried WE or TA and WE previously maintained in a hot room (70 °C) for 3 days had a negative effect on rat growth and protein utilisation. In the case of WE products this was substantiated by poor digestibility of essential amino acids, including lysine, threonine and, to some extent, methionine. When compared with the control treatments, inclusion of heat‐treated or irradiated TA in the rat diets reduced the population of Enterobacteriaceae. Copyright © 2006 Society of Chemical Industry
Glycogen debranching enzyme and some other factors relating to post‐mortem pH decrease in poultry muscles
Authors: Ylä‐Ajos Maria , Ruusunen Marita , Puolanne Eero 
Published: December 2006

AbstractThe objective of this study was to investigate the activity of glycogen debranching enzyme (GDE, EC 3.2.1.68) in chicken pectoralis superficialis (PS) and quadriceps femoris (QF) muscle post‐mortem. In addition, some other factors relating to pH decrease, such as the activity of glycogen phosphorylase (EC 2.4.1.1) and glycolytic potential were studied. Enzyme activities, glycogen content and lactate content were measured in Ross breed broiler chicken muscles obtained 25 min after stunning. An interesting discrepancy in the activities of the two glycogen degrading enzymes, GDE and phosphorylase, between muscles was found. In light PS muscle, phosphorylase activity was higher (P < 0.001), but GDE activity was lower (P < 0.001) than in dark QF muscle. Buffering capacity and glycolytic potential were higher in PS muscle than in QF muscle. The possible need for high buffering capacity and low GDE activity in PS muscle to protect living muscle from rapid pH decrease was discussed. GDE, together with glycolytic potential, accounted for 40% of the variation in ultimate pH in QF muscle and 61% in PS muscle. Considering the low activity of GDE together with the high activity of phosphorylase found in both muscles, the results of the present study support the hypothesis that GDE may restrict the rate of glycogen degradation. Copyright © 2006 Society of Chemical Industry
Ultrasound‐assisted extraction of ginsenosides in supercritical CO2 reverse microemulsions
Authors: Luo Denglin , Qiu Taiqiu , Lu Qun 
Published: December 2006

AbstractUltrasound‐assisted extraction of ginsenosides from ginseng in supercritical CO2 reverse microemulsions formed by bis(2‐ethylhexyl) sodium sulfosuccinate (AOT) was studied. Prior to extraction the ginseng was soaked in water for 12 h. It was found that ultrasound significantly enhanced supercritical CO2 reverse microemulsion extraction. The ginsenoside extraction yield from supercritical CO2 reverse microemulsion with ultrasound of 20 kHz, 15.2 W cm−2 and 3/6 s was 2.63 times that without ultrasound at 24 MPa extraction pressure, 45 °C extraction temperature, 4 h extraction time, 5 MPa separation pressure, 55 °C separation temperature and 2 L h−1 CO2 flow rate with 140 mL of 0.07 mol L−1 AOT/ethanol. The maximum extraction yields of ginsenosides from different concentrations of reverse microemulsions were obtained at different ultrasonic intensities. The extraction yield with 20 kHz ultrasound was higher than that with 38 kHz ultrasound at suitably low intensity; however, it was lower at high intensity. The yield improvement may be basically attributed to the mechanical and thermal effects of ultrasound. Copyright © 2006 Society of Chemical Industry
Effects of heat treatment on the quality and storage life of sweet potato
Authors: Hu Wenzhong , Tanaka Shun‐Ichiro 
Published: December 2006

AbstractThe effects of heat treatment (50 °C) on the sprouting inhibition and spoilage of sweet potato roots (curing temperature: 29 °C) stored in wrapper‐type cold store (WTCS) were determined during year‐long storage. The quality attributes of sweet potato were also evaluated. The results indicated that hot water treatment significantly inhibited sprouting and decay of sweet potato for the storage period. It also showed that there were no significant differences in starch properties in terms of pasting properties, enthalpy and temperatures onset (TO), peak (TP) and endset (TE) of gelatinisation of sweet potato starches among all the treatments, especially between heat‐treated and without‐heat‐treated samples. Also, hot water treatment did not have any significant impact on the internal components' quality of the roots: less than 4% of the year‐long stored roots were discarded due to spoilage. Heat treatment supplied a lethal dose of heat to surface pathogens and cauterised the eyes without damaging the nutritional and processing qualities of sweet potato. The success of storage experiments in prolonging sweet potato stored in WTCS by heat treatment was obtained from the effective control of weight loss, sprouting and decay without influence on quality characteristics. This new technique opens a new avenue to prolonging the storage life of sweet potato with good quality and minimal loss. Copyright © 2006 Society of Chemical Industry
Effect of Lactobacillus cultures on microbiological, chemical and odour changes during storage of rainbow trout fillets
Authors: Katikou Panagiota , Ambrosiadis Ioannis , Georgantelis Dimitrios , Koidis Pavlos , Georgakis Spyridon A 
Published: December 2006

AbstractThe purpose of this study was to investigate the effect of applying two Lactobacillus protective cultures on microbiological, chemical and odour changes during storage of refrigerated vacuum‐packed rainbow trout (Oncorrynchus mykiss) fillets. Lactobacillus sakei CECT 4808 and Lb. curvatus CECT 904T were inoculated individually or in combination into rainbow trout fillets. The samples were vacuum‐packed and stored at 4 ± 0.5 °C and were assessed during a 20‐day storage period for microbiological (Enterobacteriaceae, Pseudomonas spp., lactic acid bacteria (LAB), H2S‐producing bacteria, yeasts and moulds) and chemical (pH, total volatile basic nitrogen, lipid oxidation) parameters and off‐odour. Samples inoculated with Lb. sakei and with both strains had significantly (P≤0.05) lower counts of all microbiological spoilage indicator organisms (Enterobacteriaceae, Pseudomonas spp., H2S‐producing bacteria, yeasts and moulds) than those inoculated with Lb. curvatus or the controls. All chemical parameters examined and off‐odour scores were also significantly (P≤0.05) improved in the samples inoculated with Lb. sakei or with both strains compared with those inoculated with Lb. curvatus or the controls. Lb. sakei generally showed a better preservative effect (P≤0.05) than the combination of strains. Inoculation with Lb. sakei CECT 4808 could provide an additional hurdle to improve shelf‐life of refrigerated vacuum‐packaged trout fillets, as inoculation with this strain resulted in extension of shelf‐life by 5 days. Furthermore, this strain showed some antioxidative ability, which could retard lipid oxidation in fish. Copyright © 2006 Society of Chemical Industry
Structural and conformational analysis of two native procyanidin trimers
Authors: Tarascou Isabelle , Ducasse Marie‐Agnès , Dufourc Erick J. , Moskau Detlef , Fouquet Eric , Laguerre Michel , Pianet Isabelle 
Published: December 2006

AbstractThe structure and conformation of two native procyanidin trimers in water have been determined using 2D NMR and molecular mechanics. The results show the existence of four rotameric forms, one of which is predominant (60 to 80%). These four rotamers are shown to be in slow to intermediate exchange on the NMR timescale. Both trimers, whose structures vary owing to a different substitution of one carbon atom, adopt conformations in which stacking between different phenolic rings is favored. Copyright © 2006 John Wiley & Sons, Ltd.
Three‐dimensional NMR Spectroscopy of organic molecules by random sampling of evolution time space and multidimensional Fourier transformation
Authors: Misiak Maria , Koźmiński Wiktor 
Published: December 2006

AbstractIn this communication we present the application of a new method, which enables one to acquire 3D NMR spectra in a reasonable time and preserves high resolution in indirectly detected domains. The new method is based on random distribution of time domain data points followed by Quaternion FT with respect to two time variables in one step.The experimental examples include three‐dimensional spectra of strychnine in CDCl3, TOCSY‐HSQC, COSY‐HMBC, and the new technique proposed here: heteronuclear single quantum multiple bond correlation (HSQMBC). The obtained spectra are compared to those recorded at the same time employing the conventional acquisition scheme. We show that high‐quality 3D spectra of organic compounds can be obtained in reasonable experimental time and that they are of great interest in cases when direct analysis of 2D spectra is difficult. Copyright © 2006 John Wiley & Sons, Ltd.
Apparent diffusion coefficient of the prostate in men prior to biopsy: determination of a cut‐off value to predict malignancy of the peripheral zone
Authors: Kumar Virendra , Jagannathan N. R. , Kumar Rajeev , Thulkar S. , Gupta S. Dutta , Dwivedi S. N. , Hemal A. K. , Gupta N. P. 
Published: December 2006

AbstractDetermination of the apparent diffusion coefficient (ADC) of the prostate in men (n = 60) with raised prostate‐specific antigen (PSA) or an abnormal digital rectal examination (DRE) prior to transrectal ultrasound (TRUS) guided biopsy using endorectal DWI is reported. Patients were categorized into different groups based on their PSA levels. The mean ADC was calculated from a number of regions of interest (ROIs) for the whole of the peripheral zone (PZ) and the central gland (CG). A total of 1108 ROIs were analyzed from 60 patients. The mean ADC value of the PZ was higher than that of the CG in controls. A total of 23 out of 60 patients were positive for malignancy on biopsy, and the mean ADC of the PZ was lower in these patients compared with those who were negative. Moreover, the mean ADC obtained for the whole of the PZ of the prostate in different groups of patients and controls showed a decreasing trend. A plot between PSA and mean ADC for the PZ showed non‐linear association with logarithmic decrease in ADC. The mean ADC of the CG was not significantly different in patients who were positive or negative for malignancy in biopsy. In addition, a cut‐off value of 1.17 × 10−3 mm2/s (sensitivity = 73% and specificity = 74%, area under the curve = 0.83) for the mean ADC for the whole of the PZ of patients was determined by using the receiver operating characteristic curve (ROC) to predict malignancy of the PZ. Copyright © 2006 John Wiley & Sons, Ltd.
A simple mechanism for stabilizing network queues in TCP/IP networks
Authors: Aweya James , Ouellette Michel , Montuno Delfin Y. 
Published: December 2006

AbstractIn this paper we determine the stability bounds for the DRED active queue management (AQM) algorithm using a previously developed nonlinear dynamic model of TCP. We develop a second‐order linear model with time delay by linearizing the nonlinear model. Using the Pade approximation of time‐delayed systeme−R0s, whereR0is the delay in the system, we then determine the range of stabilizing gains of DRED when controlling the second‐order system with time delayR0. We also present examples showing the stability bounds of the DRED controller gain for networks with different parameters such as link capacity, load level, and round‐trip time. In addition, we describe an efficient implementation of the DRED AQM algorithm. Copyright © 2006 John Wiley & Sons, Ltd.
Numerical exploration of flow topology and vortex stability in a curved duct
Authors: Tsai S. F. , Sheu Tony W. H. 
Published: December 2006

AbstractWe performed incompressible flow simulation in a square duct with 90° bend and a curvature radius of 2.3 to extend our understanding of the vortical flow development in the bend. The solutions for the flow investigated at the Reynolds number of Re=790 are obtained in a tri‐quadratic element system, where velocities stagger the pressure working variable, using the streamline‐upwind finite element model and the BiCGSTAB iterative solver. The simulated results reveal that centrifugal force convects the quickly moving fluid particles towards the outer wall. The axial velocity, as a result, shows twin peaks in the curved channel. At about θ=66°, the secondary flow shows three complex pairs of vortices. Also noteworthy is the formation of a downstream spiralling flow motion. To better elucidate the dominating three‐dimensional flow nature, the topological study of limiting streamlines was undertaken. Insight into the longitudinal flow instability is gained by tracking the formation and diminishing of limiting cycles. Copyright © 2006 John Wiley & Sons, Ltd.
The significance of LMO2 expression in the progression of prostate cancer
Authors: Ma S , Guan XY , Beh PSL , Wong KY , Chan YP , Yuen HF , Vielkind J , Chan KW 
Published: December 2006

AbstractLIM domain only 2 (LMO2) proteins are important regulators in determining cell fate and controlling cell growth and differentiation. This study has investigated LMO2 expression in human prostatic tissue specimens, prostate cancer cell lines, and xenografts; and has assessed the possible role and mechanism of LMO2 in prostate carcinogenesis. Immunohistochemical analysis on a tissue microarray consisting of 91 human prostate specimens, including normal, prostatic hyperplasia, high‐grade prostatic intraepithelial neoplasia, and invasive carcinoma, revealed that overexpression of LMO2 was significantly associated with advanced tumour stage, as measured by Gleason score (p = 0.012), as well as with the development of distant metastasis (p = 0.018). These data were supported by quantitative real‐time PCR experiments, where LMO2 mRNA levels were found to be significantly higher in prostate tumour specimen than in normal epithelium (p = 0.037). The expression of LMO2 in cell lines and xenografts representing androgen‐dependent (AD) and androgen‐independent (AI) prostate cancer stages was further studied. Consistent with the in vivo data, LMO2 mRNA and protein were found to be overexpressed in the more aggressive AI cells (PC3, DU145, and AI CWR22 xenografts) compared with less aggressive AD cells (LNCaP and AD CWR22 xenografts). Furthermore, stable introduction of LMO2 into LNCaP cells conferred enhanced cell motility and invasiveness in vitro, accompanied by down‐regulation of E‐cadherin expression. Taken together, these findings provide the first evidence to support the hypothesis that LMO2 may play an important role in prostate cancer progression, possibly via repression of E‐cadherin expression. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Antazida – Ein historischer Überblick: Konstanz und Wandel im Lauf der Jahrhunderte
Authors: Meyer Wolfgang 
Published: December 2006

AbstractMineralische antazide Arzneistoffe wurden über Jahrtausende hinweg zur Behandlung von gastrointestinalen Beschwerden eingesetzt. Doch erst mit der Entdeckung der Magensäure zu Beginn des 19. Jahrhunderts erfolgte eine intensivere Erforschung dieser Substanzklasse. Antazida waren dann fast 200 Jahre lang eine der wichtigsten Stützen in der konservativen Ulkustherapie. Einen Höhepunkt markiert die von Sippy nach dem Ersten Weltkrieg entwickelte Hochdosistherapie. Vor ca. 30 Jahren begann sich jedoch das Bild zu ändern. Mit der Einführung der H2‐Rezeptorantagonisten schwand die Bedeutung der Antazida, obwohl im direkten klinischen Vergleich ihre therapeutische Gleichwertigkeit gezeigt und auch neue pharmakologische Eigenschaften belegt werden konnten. Man sprach sogar von einer Renaissance der Antazida. Durch die Entdeckung von Helicobacter pylori und die Einführung der Protonenpumpenhemmer vor ca. 20 Jahren wurden die Antazida bei der Primärbehandlung des Ulcus ventriculi et duodeni und der gastro‐ösophagealen Refluxkrankheit indes endgültig in den Hintergrund gedrängt. Gleichwohl spielen sie in der Selbstmedikation auch heute noch eine bedeutende Rolle.
Medizinische Chemie von Histamin‐H2‐Rezeptorantagonisten: Klassische Wirkstoffentwicklung
Authors: Kubas Holger , Stark Holger 
Published: December 2006

AbstractCimetidin war der erste therapeutisch eingesetzte “Säureblocker” und revolutionierte vor etwa 30 Jahren die Therapie peptischer Erkrankungen. Über systematische und rationale Optimierungsstrategien werden die Wege zum ersten Wirkstoff mit Marktreife und zu weiteren Entwicklungen aufgezeigt. Hierbei spielen Affinität, Bioverfügbarkeit und Interaktionen besondere Rollen.
Antazida – effizient und preiswert: Einfache anorganische Verbindungen mit großer Wirkung
Authors: Wagner Matthias 
Published: December 2006

AbstractVor allem bei Sodbrennen und säurebedingten Magenbeschwerden, also den häufigsten Krankheitsbildern des oberen Gastrointestinaltraktes, gelten Antazida auch heute noch als geeignete Arzneimittel. Die in diesem Artikel beschriebenen Nebenwirkungen bergen bei einer adäquaten Therapie mit Antazida kein hohes Gefahrenpotenzial, sondern sind nur dann zu befürchten, wenn außergewöhnliche Umstände im Sinne einer pathologischen Resorption und/oder einer gestörten Elimination die Pharmakokinetik der Antazida beeinflussen. Generell sind Antazida nach allgemeiner Überzeugung gut verträglich, da ihr hauptsächlicher Wirkort nicht systemisch ist.
Antazida und H2‐Antihistaminika bei Hyperazidität: Wissenswertes zu Nebenwirkungen und Interaktionen
Authors: Wegat Tanja , Metzman Katrin , Leuner Kristina , Müller Walter E. 
Published: December 2006

AbstractDer Einsatz von Antazida und H2‐Blockern in der Selbstmedikation des Sodbrennens stellt den Apotheker vor die Aufgabe, unter den OTC‐Produkten ein passendes Präparat auszuwählen. Im Bedarfsfall sollte die Abklärung einer Refluxösophagitis oder Ulkuserkrankung durch den Arzt erfolgen. Wie die Therapie im Hinblick auf Verträglichkeit, Interaktionen und Einnahmemodalitäten am besten unterstützt werden kann, soll dieser Beitrag kurz zusammenfassen.
Selbstmedikation mit Antazida und H2‐Antihistaminika. Was tun bei Sodbrennen und Co.?
Authors: Martin Eric 
Published: December 2006

AbstractMittel zur Behandlung von Sodbrennen spielen in der Selbstmedikation traditionell eine bedeutsame Rolle. Mit Antazida und H2‐Antihistaminika stehen zwei Gruppen von Wirkstoffen zur Verfügung, deren Wirksamkeit und Risikoprofil gut eingeschätzt werden können und die folglich ein hohes Maß an Sicherheit für die Selbstmedikation bringen. Unerwünschte Arzneimittelwirkungen sind in der Regel gutartig, mögliche Wechselwirkungen einschlägig bekannt und als solche meist gut vermeidbar. Substanzielle Risiken können indessen von einem unkritischen oder nicht indizierten Einsatz herrühren, von einer Verschleppung einer ärztlichen Diagnosestellung bzw. einer Maskierung schwerwiegender Erkrankungen. Insofern ist der Patient ohne jede Einschränkung auf eine sorgfältige Beratung und Betreuung angewiesen.