bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endothelial lipase-modified high-density lipoprotein exhibits diminished ability to mediate SR-BI (scavenger receptor B type I)-dependent free-cholesterol efflux
Authors: GAUSTER Martin , OSKOLKOVA Olga V. , INNERLOHINGER Josef , GLATTER Otto , KNIPPING Gabriele , FRANK Saša 
Published: August 2004

Endothelial lipase (EL) is a phospholipase with little triacylglycerol lipase activity. To assess structural and functional properties of EL-HDL (EL-modified high-density lipoprotein), HDL was incubated with conditioned medium from Cos-7 cells infected with adenovirus encoding human EL. After re-isolation of HDL by ultracentrifugation, TLC and HPLC analyses revealed that EL-HDL was markedly depleted in phosphatidylcholine and enriched in lyso-phosphatidylcholine compared with LacZ-HDL (control HDL) incubated with conditioned medium from Cos-7 cells infected with adenovirus encoding β-galactosidase. The EL-HDL was enriched in non-esterified fatty acids and, as revealed by lipid electrophoresis, was more negatively charged than control HDL. The HDL particle size as well as the total cholesterol, free cholesterol and triacylglycerol content of HDL were not significantly altered after EL modification. The ability of EL-HDL to mediate 3H-cholesterol efflux from SR-BI (scavenger receptor B type I) overexpressing Chinese-hamster ovary cells was impaired and markedly lower compared with LacZ-HDL at HDL concentrations of 100 μg/ml and above. Studies with 125I-labelled HDL showed almost unaltered binding affinity (Km values) and a slightly but significantly decreased binding capacity (Bmax values) of EL-HDL to SR-BI, compared with LacZ-HDL. The ATP-binding-cassette transporter A1-dependent cholesterol and phospholipid effluxes were not affected by EL modification. From these results, we concluded that EL modification alters chemical composition and physical properties of HDL, resulting in its decreased binding capacity to SR-BI and a diminished ability to mediate SR-BI-dependent cholesterol efflux.
Cloning and expression of an inhibitor of microbial metalloproteinases from insects contributing to innate immunity
Authors: CLERMONT Anja , WEDDE Marianne , SEITZ Volkhard , PODSIADLOWSKI Lars , LENZE Dido , HUMMEL Michael , VILCINSKAS Andreas 
Published: August 2004

The first IMPI (inhibitor of metalloproteinases from insects) was identified in the greater wax moth, Galleria mellonella [Wedde, Weise, Kopacek, Franke and Vilcinskas (1998) Eur. J. Biochem. 255, 535–543]. Here we report cloning and expression of a cDNA coding for this IMPI. The IMPI mRNA was identified among the induced transcripts from a subtractive and suppressive PCR analysis after bacterial challenge of G. mellonella larvae. Induced expression of the IMPI during a humoral immune response was confirmed by real-time PCR, which documented up to 500 times higher amounts of IMPI mRNA in immunized larvae in comparison with untreated ones. The IMPI sequence shares no similarity with those of tissue inhibitors of metalloproteinases or other natural inhibitors of metalloproteinases, and the recombinant IMPI specifically inhibits thermolysin-like metalloproteinases, but not matrix metalloproteinases. These results support the hypothesis that the IMPI represents a novel type of immune-related protein which is induced and processed during the G. mellonella humoral immune response to inactivate pathogen-associated thermolysin-like metalloproteinases.
Heterodimeric interaction and interfaces of S100A1 and S100P
Authors: WANG Guozheng , ZHANG Shu , FERNIG David G. , SPILLER David , MARTIN-FERNANDEZ Marisa , ZHANG Hongmei , DING Yi , RAO Zihe , RUDLAND Philip S. , BARRACLOUGH Roger 
Published: August 2004

With the widespread use of yeast two-hybrid systems, many heterodimeric forms of S100 proteins have been found, although their biological significance is unknown. In the present study, S100A1 was found to interact with another S100 protein, S100P, by using the yeast two-hybrid system. The binding parameters of the interaction were obtained using an optical biosensor and show that S100P has a slightly higher affinity for S100A1 (Kd=10–20 nM) when compared with that for self-association (Kd=40–120 nM). The physical interaction of S100A1 and S100P was also demonstrated in living mammalian cells using a fluorescence resonance energy transfer technique. Preincubation of recombinant S100P with S100A1, before the biosensor assay, reduced by up to 50% the binding of S100P to a recombinant C-terminal fragment of non-muscle myosin A, one of its target molecules. Site-specific mutations of S100P and S100A1, combined with homology modelling of an S100P/S100A1 heterodimer using known S100P and S100A1 structures, allowed the hydrophobic interactions at the dimeric interface of the heterodimer to be defined and provide an explanation for the heterodimerization of S100P and S100A1 at the molecular level. These results have revealed the similarities and the differences between the S100P homodimer and the S100A1/S100P heterodimer.
Fructosamine 3-kinase-related protein and deglycation in human erythrocytes
Authors: COLLARD François , WIAME Elsa , BERGANS Niki , FORTPIED Juliette , VERTOMMEN Didier , VANSTAPEL Florent , DELPIERRE Ghislain , VAN SCHAFTINGEN Emile 
Published: August 2004

Fructosamine 3-kinase (FN3K), an enzyme initially identified in erythrocytes, catalyses the phosphorylation of fructosamines on their third carbon, leading to their destabilization and their removal from protein. We show that human erythrocytes also contain FN3K-related protein (FN3K-RP), an enzyme that phosphorylates psicosamines and ribulosamines, but not fructosamines, on the third carbon of their sugar moiety. Protein-bound psicosamine 3-phosphates and ribulosamine 3-phosphates are unstable, decomposing at pH 7.1 and 37 °C with half-lives of 8.8 h and 25 min respectively, as compared with 7 h for fructosamine 3-phosphates. NMR analysis indicated that 1-deoxy-1-morpholinopsicose (DMP, a substrate for FN3K and FN3K-RP), like 1-deoxy-1-morpholinofructose (DMF, a substrate of FN3K), penetrated erythrocytes and was converted into the corresponding 3-phospho-derivative. Incubation of erythrocytes with 50 mM allose, 200 mM glucose or 10 mM ribose for 24 h resulted in the accumulation of glycated haemoglobin, and this accumulation was approx. 1.9–2.6-fold higher if DMP, a competitive inhibitor of both FN3K and FN3K-RP, was present in the incubation medium. Incubation with 50 mM allose or 200 mM glucose also caused the accumulation of ketoamine 3-phosphates, which was inhibited by DMP. By contrast, DMF, a specific inhibitor of FN3K, only affected the glucose-dependent accumulation of glycated haemoglobin and ketoamine 3-phosphates. These data indicate that FN3K-RP can phosphorylate intracellular, protein-bound psicosamines and ribulosamines, thus leading to deglycation.
The role of the initiation surveillance complex in promoting efficient protein synthesis
Authors: Gallie D.R. 
Published: August 2004

Initiation is most often the rate-limiting step of translation. Translation initiation requires the involvement of numerous factors that assist binding of the 40 S ribosomal subunit to an mRNA and the assembly of the 80 S ribosome at the correct initiation codon. Recruitment of an initiation surveillance complex is required for translation and serves to identify mRNAs that are structurally and functionally competent for translation. For most cellular mRNAs, recruitment of the surveillance complex requires the 5′-cap and 3′-poly(A) tail. However, some cellular and viral mRNAs that naturally lack either of these have evolved alternatives that serve to recruit the complex. The initiation surveillance complex functions to stabilize eIF4F (where eIF stands for eukaryotic initiation factor), the cap-binding complex, to the cap; promote eIF4A helicase activity to remove secondary structure in the 5′-leader that might otherwise reduce 40 S ribosomal subunit scanning; promote eIF4B binding to increase eIF4A/eIF4F function and stabilize binding of the poly(A)-binding protein to the poly(A) tail. The surveillance complex is regulated through changes in phosphorylation in response to environmental conditions or by developmental signals as a means to regulate globally protein synthesis. Thus the initiation surveillance complex ensures that only intact mRNAs are recruited for translation and serves to regulate protein synthesis.
Regulation of chloroplast translation: interactions of RNA elements, RNA-binding proteins and the plastid ribosome
Authors: Manuell A. , Beligni M.V. , Yamaguchi K. , Mayfield S.P. 
Published: August 2004

Chloroplast gene expression is primarily controlled during the translation of plastid mRNAs into proteins, and genetic studies have identified cis-acting RNA elements and trans-acting protein factors required for chloroplast translation. Biochemical analysis has identified both general and specific mRNA-binding proteins as components of the regulation of chloroplast translation, and has revealed that chloroplast translation is related to bacterial translation but is more complex. Utilizing proteomic and bioinformatic analyses, we have identified the proteins that function in chloroplast translation, including a complete set of chloroplast ribosomal proteins, and homologues of the 70 S initiation, elongation and termination factors. These analyses show that the translational apparatus of chloroplasts is related to that of bacteria, but has adopted a number of eukaryotic mechanisms to facilitate and regulate chloroplast translation.
Accuracy analysis, dem generation and validation using russian tk‐350 stereo‐images
Authors: Büyüksalih Gürcan , Koçak Güven , Oruç Murat , Akçin Hakan , Jacobsen Karsten 
Published: August 2004

AbstractTK‐350 stereo‐scenes of the Zonguldak testfield in the north‐west of Turkey have been analysed. The imagery had a base‐to‐height ratio of 0·52 and covered an area of 200 km × 300 km, with each pixel representing 10 m on the ground. Control points digitised from 1:25 000 scale topographic maps were used in the test. A bundle orientation was executed using the University of Hanover program BLUH and PCI Geomatica OrthoEngine AE software packages. Tests revealed that TK‐350 stereo‐images can yield 3D geopositioning to an accuracy of about 10 m in planimetry and 17 m in height. A 40 m resolution digital elevation model (DEM) was generated by the PCI system and compared against a reference DEM, which was derived from digitised contour lines provided by 1:25 000 scale topographic maps. This comparison showed that accuracy depends mainly on the surface structure and the slope of the local terrain. Root mean square errors in height were found to be about 27 and 39 m outside and inside forested areas, respectively. The matched DEM demonstrated a systematic shift against the reference DEM visible as an asymmetric shift in the frequency distribution. This is perhaps caused by the presence of vegetation and buildings.
Visibility Analysis In Vision Metrology Network Design
Authors: Saadatseresht Mohammad , Fraser Clive S. , Samadzadegan Farhad , Azizi Ali 
Published: August 2004

AbstractThe aim of this paper is to present a method whereby accuracy enhancement of an existing photogrammetric network is achieved through the automatic selection of additional camera stations. The determination of the positions of these ‘‘accuracy fulfilment’’ camera stations is based upon what has been termed ‘‘visibility uncertainty prediction modelling’’ of visibility constraints derived from the existing network geometry. Following a review of vision constraints in network design, the concepts of visibility uncertainty prediction and visibility uncertainty spheres are introduced. These provide a mechanism to predict the visibility of current object target points for the new accuracy fulfilment images. This in turn aids in network design improvement. The visibility uncertainty modelling is then illustrated for two close range photogrammetric network configurations, for which the test results demonstrate that the proposed model can reliably predict target visibility with an overall certainty of 75%.
MARGINAL DETERRENCE THROUGH AMBIENT ENVIRONMENTAL INSPECTIONS
Authors: Franckx Laurent 
Published: August 2004

AbstractWe consider the enforcement of an environmental standard if the probabilities of inspection are determined by an inspection agency who permanently monitors ambient pollution. This monitoring creates strategic interactions between polluters, which imply that the probability of inspection is increasing in the transgression level. These interactions also imply that marginal deterrence is possible, even with penalties that are not increasing in the transgression levels.
Combination of micro suction cups and time‐domain reflectometry to measure osmotic potential gradients between bulk soil and rhizosphere at high resolution in time and space
Authors: Vetterlein D. , Jahn R. 
Published: August 2004

SummaryA prerequisite to investigate the importance of osmotic potential (Ψo) in relation to matric potential (Ψm) in the soil for water uptake is the existence of a method that measures the temporal and spatial dynamics of Ψo in the vicinity of roots. One method for measuring Ψoin situ is the collection of soil solution with micro suction cups, the spatial resolution of which is suitable for rhizosphere studies. A major drawback of soil solution sampling is the disturbance of soil solution equilibrium, which makes frequent measurements impossible, so another method is required to provide information on the temporal dynamics of Ψo. The time‐domain reflectometry (TDR) technique might be suitable as the signal attenuation (σ) shows a close linear correlation with the salt concentration for a known soil water content. The temporal resolution of the TDR technique is high and the measurement has no impact on soil solution equilibrium. However, the spatial resolution of the TDR technique is too coarse to be used on its own in rhizosphere studies.We used a combination of TDR (fine temporal resolution) and micro suction cups (fine spatial resolution) to measure Ψo in a model system with Zea mays grown in quartz substrates. Osmotic potential changed continuously with time, and a steep gradient between bulk soil and the root compartment developed during the 39‐day growing period. The steepest gradient measured over a distance of 6 mm across the nylon net, separating the bulk soil from the root compartment, was −365 kPa. The combination of both methods made it possible to extend the time interval between micro suction cup samplings and thus minimize the impact of sampling on soil solution equilibrium. Problems of separate calibration were avoided by calibrating the TDR measurements against the results obtained with the micro suction cups within the same experiment.
Fractionated extraction of polycyclic aromatic hydrocarbons (PAHs) from polluted soils: estimation of the PAH fraction degradable through bioremediation
Authors: Thiele‐Bruhn S. , Brümmer G.W. 
Published: August 2004

SummaryChemical extractions were tested to estimate the fraction of 15 polycyclic aromatic hydrocarbons (PAHs) in polluted soils degradable through bioremediation. Of 30 soil samples, differing in PAH concentrations, from 10 long‐term polluted sites, four were used in screening tests conducted with 14 different extractants. PAH extractability increased in the order salt solutions < surfactant solutions < organic solvents and organic solvent–water mixtures. Closest correlations (r = 0.73–0.91) and ratios of c. 1:1 of the extracted to the degradable PAH concentrations were found with aqueous solutions of two surfactants (Genapol UDD 88, Synperonic LF/RA 30).The PAH extractability by surfactant solutions increased with surfactant concentration (0–50 mg ml−1) and with decreasing degree of PAH condensation (6–2 rings). Kinetic behaviour of PAH solubilization by surfactants resembled the kinetics of PAH degradation (r = 0.84–0.99). With repeated extractions, a finite fraction of PAHs was extracted, which is thought to be the mobile and mobilizable PAH fraction, the latter being controlled by back‐diffusion from intra‐ and inter‐particle sites.Experiments with all 30 soil samples and a priori testing with an additional 10 soil samples confirmed that single extractions with surfactant solutions (5 mg ml−1; soil:solution ratio 1:20) were suitable for estimating the degradable fraction of PAHs in soil. With separate linear regression equations for PAHs grouped according to their degree of condensation, the extracted concentrations described the degradable concentrations with correlation coefficients (r) ranging from 0.62 to 0.80 (P < 0.001). PAH extractions with the surfactant solutions can be used to assess the prospects of bioremediation of PAH‐polluted sites.
The impact of ivermectin treatment alone and when in parallel with Simulium neavei elimination on onchocerciasis in Uganda
Authors: Ndyomugyenyi Richard , Tukesiga Ephraim , Büttner Dietrich W. , Garms Rolf 
Published: August 2004

SummaryThe study was conducted in August 2002 in Kigoyera parish in Kyenjojo district, where ivermectin treatment had been the strategy to control onchocerciasis since 1991 and was later supplemented with Simulium neavei control in 1995 and subsequent elimination; and in July 2003 in Kicece parish in Kamwenge district, where ivermectin treatment alone had been the strategy used to control onchocerciasis since 1991. Our objective was to examine and compare the impact of ivermectin treatment alone and when in parallel with S. neavei elimination on nodule and microfilariae carrier rates and on onchocercal dermatitis to provide baseline data that could be used to monitor the trends of microfilariae carrier rates for decision‐making on when to discontinue ivermectin treatment. The combined interventions had significantly reduced onchocercal dermatitis from 34% pre‐control to 2.9% (P < 0.001), microfilariae carrier rate from 88 to 7.5% (P < 0.001) and nodule prevalence from 49 to 19.2% (P < 0.001). Ivermectin treatment alone had also reduced onchocercal dermatitis prevalence from 34.2% pre‐control to 9.5% (P < 0.001), the microfilariae carrier rate from 78 to 27.8% (P < 0.001) and nodule prevalence from 49.1 to 14.2% (P < 0.001). None of the children under 10 years were nodule or microfilariae carriers in both study areas. Histological examination of eight nodules extirpated from patients in Kigoyera identified five male and 12 female adult worms that were all old and alive. Five live and one dead female worms and one live male worm were identified from nodules extirpated from patients in Kicece. There was no female worm with embryogenesis from the nodules obtained from Kigoyera while two female worms from five nodules obtained from Kicece still showed a few embryos. Two female worms in each of the study area had sperms in uteri indicating that male worms were still active. Ivermectin treatment in parallel with vector elimination had a greater impact on onchocercal dermatitis and microfilariae carrier rates than ivermectin treatment alone. It would be worthwhile considering supplementation of ivermectin treatment with vector elimination in all isolated foci with S. neavei transmission to hasten the elimination of onchocerciasis as a public health and socio‐economic problem in those foci.
Rapid detection of human HLA transgenes in pigs by fluorescence in situ hybridization (FISH) for adjuvant study of human xenotransplantation
Authors: Wang Bao‐Tyan , Tu Ching‐Fu , Hsieh Lie‐Jiau , Tai Hao‐Chih , Chiu Ya‐Lan , Lee Jang‐Ming , Kuo Shou‐Jen , Tsuji Kimiyoshi , Lee Chun‐Jean 
Published: August 2004

Abstract:  Objectives:  We have recently generated several lines of transgenic pigs for HLA‐DP and ‐DQ to elucidate the role of HLA‐II antigens in the modulation of cell‐mediated rejection of xenotransplantation. Using fluorescence in situ hybridization (FISH) analysis, the aim of this study was to determine integration sites and to test zygosity of these transgenes in the piglets after cross mating.Methods:  Blood lymphocytes of transgenic pigs for HLA‐DP and ‐DQ were collected and cultured. Chromosome spreads were prepared by standard methodology. Gene constructs of HLA‐DP A1+B1, ‐DQ A1 & B1 were labeled with fluorescein isothiocyanate or Texas Red by nick‐translation. Hybridization was based on a standard FISH protocol.Results:  FISH analysis revealed that the HLA‐DP probe hybridized to porcine chromosome 6, while both HLA‐DQ A1 and B1 probes hybridized to porcine chromosome 11 at the same site. There was no cross‐hybridization of HLA transgenes to the swine leukocyte antigen complex. Mosaic integration of HLA‐DQ transgenes in the genome of F0, but full penetrance in F1 after selective breeding was observed. Both HLA‐DP and HLA‐DQ lines were determined to be heterozygous at the integration site.Conclusion:  By FISH, we have detected specific integration sites of the HLA‐DP and ‐DQ transgenes in pig genome and determined mosaic levels and zygosity types of these transgenes. We conclude that FISH is both sensitive and labor‐efficient in confirming and differentiating transgenic pigs for multiple rejection‐regulatory genes by visualizing individual integration sites in chromosomes or interphase nuclei.
Immunological rapid urease test using monoclonal antibody for Helicobacter pylori
Authors: NAKATA HIROYA , ITOH HIDEKAZU , ISHIGUCHI TADASHI , IWATA TAKUYA , SATO HIROAKI , HIGASHIMOTO YUJI , FUJIMOTO HISASHI , ICHINOSE MASAO 
Published: August 2004

AbstractBackground and Aim:  The current diagnostic methods for detecting Helicobacter pylori infection include rapid urease test (RUT), urea breath test (UBT), histology, culture, and serum antibody detection. The present study evaluated the efficacy of a novel highly specific test, an immunological RUT (IRUT), that uses a monoclonal antibody against H. pylori urease.Methods:  The clinical evaluation of the IRUT was performed in 100 subjects. Each gastric mucus sample obtained during endoscopic examination was incubated for 15 min with a solid tip coated with monoclonal antibody for H. pylori urease, and then the tip was introduced into a pH‐monitoring cell containing urea solution. The change in pH of the solution after the enzymatic reaction (delta pH) was measured. The performance of the IRUT was compared with culture, histology, RUT, and UBT.Results:  Of the 47 H. pylori‐positive subjects, 43 were IRUT positive (sensitivity, 91.5%), and of the 53 H. pylori‐negative subjects, 52 were negative (specificity, 98.1%). Compared with the usual diagnostic methods, IRUT had high sensitivity and specificity for the detection of H. pylori and was no less efficient.Conclusions:  IRUT is a sensitive, specific and very rapid (within 20 min) method of detecting H. pylori infection.
Effect of sex steroids on colonic distension‐induced delay of gastric emptying in rats
Authors: GÜNAL ÖMER , BOZKURT AYHAN , DENIZ MUSTAFA , SUNGUR MUSTAFA , YEǦ BERRAK Ç 
Published: August 2004

AbstractBackground and Aim:  The objective of the present study was to examine the effect of gonadal hormones on gastric motor response to non‐noxious and noxious stimuli of colonic distension.Methods:  Male Wistar albino rats were used. Under ketamine anesthesia some rats underwent castration (n = 24), while the rest of the rats were sham‐operated (n = 67) and divided into different groups (n = 7–8 per group). On the 15th day of surgery, liquid gastric emptying studies were commenced.Results:  Non‐noxious (P < 0.05) or noxious (P < 0.01) colonic distension inhibited gastric emptying rate. Estradiol pretreatment (20 µg/kg per day, for 5 days, s.c.) inhibited gastric motility, while estradiol pretreatment or castration of the rats prior to noxious distension prevented the delay in gastric emptying. In contrast, blockade of testosterone receptors had no effect on the delay in gastric emptying induced by either modes of distension.Conclusions:  The results suggest that sex steroids have a modulatory role on the feedback control of gastric motility induced by noxious colonic distension.