bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation of Rheological and Microstructural Properties in a Model Lipid System
Authors: Liang Baomin , Shi Yuping , Hartel Richard W. 
Published: March 2008

AbstractModel systems having different microstructures and rheological properties were obtained by controlled crystallization from a mixture of high‐melting and low‐melting lipids. Based on analysis of confocal scanning light microscopic images, the microstructural characteristics of the systems were quantified by use of different approaches including microstructure density, Euler characteristic, nearest‐neighbor analysis, fractal dimension of microstructure interface, and fractal dimension by the particle‐counting method (PCM). The solid‐fat content (SFC) of semisolid lipid samples was measured by nuclear magnetic resonance (NMR) spectroscopy and rheological properties were analyzed by compressive penetration tests with a texture analyzer. As expected, SFC had a major impact on rheological properties, but lipid crystalline microstructure also had significant effects. Correlation analysis showed that rheological properties were highly correlated with the various quantitative microstructural parameters, with the exception of the fractal dimension by the PCM. Empirical models adequately correlated rheological properties with SFC and microstructure density. Compression modulus increased by a factor of about ten as SFC increased from 0.28 to 0.51. However, for systems with the same SFC, compression modulus was dependent on microstructure. At low SFC compression modulus increased by about a factor of seven over the range of microstructures formed, whereas at higher SFC compression modulus only increased by a factor of about two.
Practical and conceptual limitations of tissue Doppler imaging to predict reverse remodelling in cardiac resynchronisation therapy
Authors: De Boeck Bart W.L. , Meine Mathias , Leenders Geert E. , Teske Arco J. , van Wessel Harry , Kirkels J. Hans , Prinzen Frits W. , Doevendans Pieter A. , Cramer Maarten J. 
Published: March 2008

AbstractBackground:Recent, conflicting results about the use of tissue Doppler imaging derived (TDI‐) asynchrony indices to predict reverse remodelling after cardiac resynchronisation therapy (CRT) have raised questions about their physiological meaning and methodological limitations.Methods:In 41 patients, baseline TDI‐derived septal to lateral delays of peak velocities (TDI‐SL), standard deviation of peak velocities over 12 segments (Ts‐SD), and peak 2D longitudinal strain (strain‐SL) were compared with volumetric response (reduction in end‐systolic volume of ≥ 15%) after at least 6 months of CRT. Timing of peak TDI velocities was compared to timing of 2DS velocities and strain‐SL. Influence of sample position, transverse motion, and interobserver inconsistency of the chosen peak velocities was assessed. Diagnostic accuracy of TDI‐based delays was compared to accuracy of visual and 2D strain‐based assessment.Results:After 7.0±3.2 months of CRT, 24 patients were classified as responders. TDI‐SL and Ts‐SD were similar between responders and nonresponders at baseline, did not predict response, and were unaffected by CRT. Visual asynchrony scoring and strain‐SL were better predictors of response than TDI‐SL and Ts‐SD. TDI measurements were highly susceptible to sample location and transverse motion components and poorly correlated with the timing of longitudinal contraction. There was a considerably poor agreement between observers with regard to scoring of TDI‐SL and Ts‐SD.Conclusion:TDI‐based measurements of asynchrony do not appear robust predictors of volume response to CRT.
Pliocene-Quaternary orogeny in the Central Tien Shan
Authors: Trifonov V.G. , Artyushkov E.V. , Dodonov A.E. , Bachmanov D.M. , Mikolaichuk A.V. , Vishnyakov F.A. 
Published: March 2008

Abstract
Formation of mountains of the Central Tien Shan is usually explained by the isostatic response of the crust to its shortening caused by the India-Eurasia collision. The rise of the region in the period from Oligocene to Late Pliocene (2 myr ago) reached ∼700 m on average, which corresponds to the isostatic response. For the last 2 myr (Late Pliocene–Quaternary), the rate of rise increased by an order of magnitude. This is proved by the coarsening of Cenozoic molasse up the sections, acceleration of cutting of drainage systems into ridges, and formation of new ridges within basins. In the Quaternary, most of intermontane basins underwent uplifting, though not so intense. The average rate of lateral crustal shortening increased ∼2–2.5 times only, and the contribution of this process to the Late Pliocene-Quaternary orogeny was no more than 10%. The acceleration of rise was caused mainly by the convective replacement of the mantle lithosphere by the less dense asthenosphere. This was due to the quick softening of the mantle lithosphere as a result of the infiltration of active fluid from the lower mantle. Such accelerations of crustal uplifting took place in the Pliocene and Quaternary in many continental regions. This evidences that mantle processes, first of all, the full or partial replacement of the mantle lithosphere by the asthenosphere, played an important role in the formation of mountains.
Estimating magnitudes of prehistoric earthquakes from landslide data: first experience in southeastern Altai
Authors: Nepop R.K. , Agatova A.R. 
Published: March 2008

Abstract
We report the first experience of deriving the magnitudes of prehistoric earthquakes in southeastern Gorny Altai from the size of largest landslides they triggered using an empirical correlation between the earthquake magnitude and the volume of associated landslides. The applicability of this relationship to the Altai region has been checked against data on the M= 7.5 Chuya earthquake of 2003 that induced a great landslide event. The paleoearthquake magnitudes derived from landslide volume are the minimum estimates; the largest magnitudes of earthquakes of about the same size and location as the Chuya event have been predicted with a simplified linear dependence of earthquake magnitude versus detachment length. The magnitudes obtained with the new approach are of a satisfactory accuracy improving proportionally for younger earthquakes. The estimates spanning magnitudes from 6.9 to largest possible in nature indicate high seismic activity of the area through the Holocene and its seismotectonic identity with the Mongolian Altai.
β-Cryptoxanthin from supplements or carotenoid-enhanced maize maintains liver vitamin A in Mongolian gerbils (Meriones unguiculatus) better than or equal to β-carotene supplements
Authors: Davis Christopher , Jing Hua , Howe Julie A. , Rocheford Torbert , Tanumihardjo Sherry A. 
Published: March 2008

Maize with enhanced provitamin A carotenoids (biofortified), accomplished through conventional plant breeding, maintains vitamin A (VA) status in Mongolian gerbils (Meriones unguiculatus). Two studies in gerbils compared the VA value of β-cryptoxanthin with β-carotene. Study 1 (n 47) examined oil supplements and study 2 (n 46) used maize with enhanced β-cryptoxanthin and β-carotene. After 4 weeks' depletion, seven or six gerbils were killed; remaining gerbils were placed into weight-matched groups of 10. In study 1, daily supplements were cottonseed oil, and 35, 35 or 17·5 nmol VA (retinyl acetate), β-cryptoxanthin or β-carotene, respectively, for 3 weeks. In study 2, one group of gerbils was fed a 50 % biofortified maize diet which contained 2·9 nmol β-cryptoxanthin and 3·2 nmol β-carotene/g feed. Other groups were given equivalent β-carotene or VA supplements based on prior-day intake from the biofortified maize or oil only for 4 weeks. In study 1, liver retinol was higher in the VA (0·74 (sd 0·11) μmol) and β-cryptoxanthin (0·65 (sd 0·10) μmol) groups than in the β-carotene (0·49 (sd 0·13) μmol) and control (0·41 (sd 0·16) μmol) groups (P < 0·05). In study 2, the VA (1·17 (sd 0·19) μmol) and maize (0·71 (sd 0·18) μmol) groups had higher liver retinol than the control (0·42 (sd 0·16) μmol) group (P < 0·05), whereas the β-carotene (0·57 (sd 0·21) μmol) group did not. Bioconversion factors (i.e. 2·74 μg β-cryptoxanthin and 2·4 μg β-carotene equivalents in maize to 1 μg retinol) were lower than the Institute of Medicine values.
Does larval aggregation pheromone of codling moth,Cydia pomonella, induce attraction or arrestment of receivers?
Authors: Jumean Z. , Wood C. , Gries G. 
Published: March 2008

AbstractCocoon-spinning larvae of the codling moth,Cydia pomonella, emit a pheromone that mediates aggregation by pupation site-seeking fifth-instar larvae. It was unknown and, thus, we tested whether the aggregation pheromone induces arrestment or attraction responses. In paired straight-tube experiment 1, fifth-instars moved faster and farther upwind toward cospecific cocoons compared to blank controls. In still-air cage experiment 2, fifth-instars selected more often as first and final choices of pupation sites those with cocooning conspecifics than those without. Finally, in Y-tube olfactometer experiment 3, fifth-instars anemotactically responded to, and preferred, side arms with cocooning conspecifics to those without. Our data provide evidence that codling moth larvae are attracted to, rather than merely arrested by, larval aggregation pheromone. These results help explain reported aggregations or clumped distributions of larvae on tree trunks, which would likely not occur if they were based merely on chance encounter of cocoon-spinning larvae by foraging larvae.
Electrocautery for cutaneous flap creation during thyroidectomy: a randomised, controlled study
Authors: Barbaros U , Erbil Y , Aksakal N , Çıtlak G , İşsever H , Bozbora A , Özarmağan S 
Published: March 2008

AbstractBackground:Although electrocautery has been used widely in surgery, the fear of delayed wound healing and infection persists. We aimed to evaluate the risk factors for wound complications and the rate of wound complications, comparing the use of electrocautery or scissors in cutaneous flap creation during thyroidectomy.Design:The study group comprised 239 consecutive patients scheduled for thyroidectomy.Subjects:Patients were randomly assigned to cutaneous flap dissection by either electrocautery (group one, n = 126) or scissors (group two, n = 113). Age, gender, body mass index, American Society of Anesthesiology score, tissue weight, operating time, incision length, cutaneous tissue depth, thyroid function and surgeon experience were recorded and compared with the rate of post-operative wound complications in both groups.Results:There were no significant differences between the overall rate of post-operative wound complications, comparing groups one and two (7.9 vs 10.6 per cent, respectively; p = 0.74). Significant positive correlations were found between wound complication and age (Spearman's rank coefficient (rs) = 0.135, p = 0.036), body mass index (rs = 0.379, p = 0.0001), cutaneous tissue depth (rs = 0.677, p = 0.0001) and tissue weight (rs = 0.643, p = 0.0001). According to logistic regression analysis, a body mass index of more than 27.5 kg/m2 was associated with a 13.7-fold increased rate of post-operative wound complications.Conclusion:When creating cutaneous flaps during thyroidectomy, the use of electrocautery is as safe as the use of scissors. Such electrocautery does not increase the risk of wound complications in thyroid surgery.
Forecasting the impacts of climate variability: lessons from the rainfed corn market in Ceará, Brazil
Authors: CHIMELI ARIASTER B. , DE SOUZA FILHO FRANCISCO DE ASSIS , HOLANDA MARCOS COSTA , PETTERINI FRANCIS CARLO 
Published: March 2008

ABSTRACTA number of studies show that climatic shocks have significant economic impacts in several regions of the world, especially in, but not limited to, developing economies. In this paper we focus on a drought-related indicator of well-being and emergency spending in the Brazilian semi-arid zone – rainfed corn market – and estimate aggregate behavioral and forecast models for this market conditional on local climate determinants. We find encouraging evidence that our approach can help policy makers buy time to help them prepare for drought mitigating actions. The analysis is applicable to economies elsewhere in the world and climatic impacts other than those caused by droughts.
Antimalarial drugs inhibit human 5‐HT3and GABAAbut not GABACreceptors
Authors: Thompson A J , Lummis S C R 
Published: March 2008

Background and purpose:Antimalarial compounds have been previously shown to inhibit rodent nicotinic acetylcholine (nACh) and 5‐HT3receptors. Here, we extend these studies to include human 5‐HT3A, 5‐HT3AB, GABAAα1β2, GABAAα1β2γ2 and GABACρ1 receptors.Experimental approach:We examined the effects of quinine, chloroquine and mefloquine on the electrophysiological properties of receptors expressed inXenopusoocytes.Key results:5‐HT3Areceptor responses were inhibited by mefloquine, quinine and chloroquine withIC50values of 0.66, 1.06 and 24.3 μM. At 5‐HT3ABreceptors, the potencies of mefloquine (IC50=2.7 μM) and quinine (15.8 μM), but not chloroquine (23.6 μM), were reduced. Mefloquine, quinine and chloroquine had higherIC50values at GABAAα1β2 (98.7, 0.40 and 0.46 mM, respectively) and GABAAα1β2γ2 receptors (0.38, 1.69 and 0.67 mM, respectively). No effect was observed at GABACρ1 receptors. At all 5‐HT3and GABAAreceptors, chloroquine displayed competitive behaviour and mefloquine was non‐competitive. Quinine was competitive at 5‐HT3Aand GABAAreceptors, but non‐competitive at 5‐HT3ABreceptors. Homology modelling in combination with automated docking suggested orientations of quinine and chloroquine at the GABAAreceptor binding site.Conclusions and implications:The effects of mefloquine, quinine and chloroquine are distinct at GABAAand GABACreceptors, whereas their effects on 5‐HT3ABreceptors are broadly similar to those at 5‐HT3Areceptors.IC50values for chloroquine and mefloquine at 5‐HT3receptors are close to therapeutic blood concentrations required for malarial treatment, suggesting that their therapeutic use could be extended to include the treatment of 5‐HT3receptor‐related disorders.British Journal of Pharmacology(2008)153, 1686–1696; doi:10.1038/bjp.2008.34; published online 3 March 2008
Gabapentin activates ROMK1 channels by a protein kinase A (PKA)‐dependent mechanism
Authors: Lee C‐H , Tsai T‐S , Liou H‐H 
Published: March 2008

Background and purpose:Gabapentin is an effective anticonvulsant. The major physiological function of renal outer medullary potassium (ROMK1) channels is to maintain the resting membrane potential (RMP). We investigated the effect of gabapentin on ROMK1 channels and the mechanism involved.Experimental approach:Xenopusoocytes were injected with mRNA coding for wild‐type or mutant ROMK1 channels and giant inside‐out patch‐clamp recordings were performed.Key results:Gabapentin increased the activity of ROMK1 channels, concentration‐dependently and enhanced the activity of wild‐type and an intracellular pH (pHi)‐gating residue mutant (K80M) channels over a range of pHi. Gabapentin also increased activity of channels mutated at phosphatidylinositol 4,5‐bisphosphate (PIP2)‐binding sites (R188Q, R217A and K218A). However, gabapentin failed to enhance channel activity in the presence of protein kinase A (PKA) inhibitors and did not activate phosphorylation site mutants (S44A, S219A or S313A), mutants that mimicked the negative charge carried by a phosphate group bound to a serine (S44D, S219D or S313D), or a mutated channel with a positive charge (S219R). These findings show that gabapentin activates ROMK1 channels independently of the pHiand not via a PIP2‐dependent pathway. The effects of gabapentin on ROMK1 channels may be due to a PKA‐mediated phosphorylation‐induced conformational change, but not to charge–charge interactions.Conclusions and implications:ROMK1 channels are the main channels responsible for maintaining the RMP during cellular excitation. Gabapentin increased the activity of ROMK1 channels by a PKA‐dependent mechanism, reducing neuronal excitability, and this may play an important role in its antiepileptic effect.
Autonomic nervous system‐dependent and ‐independent cardiovascular effects of exendin‐4 infusion in conscious rats
Authors: Gardiner S M , March J E , Kemp P A , Bennett T 
Published: March 2008

Background and purpose: Glucagon‐like peptide‐1 (GLP) receptor agonists are promising therapeutic agents for the treatment of type II diabetes, but effects other than those on glucoregulation need assessing. Cardiovascular actions of bolus doses of the GLP receptor agonist exendin‐4 have been reported, but to date the effects of continuous infusions have not been described.Experimental approach: The regional haemodynamic effects and possible underlying mechanisms of 6 h infusions of exendin‐4 were measured in conscious, chronically instrumented rats.Key results: A 6 h infusion of exendin‐4 (up to 6 pmol kg−1 min−1) only modestly influenced blood pressure, but caused substantial, opposing, regionally selective vascular effects and tachycardia. A major involvement of β‐adrenoceptors in the vasodilator and cardiac effects was identified, with little or no direct contribution from α‐adrenoceptors to the vasoconstriction seen. Under conditions where α‐ and β‐adrenoceptors were antagonized, or when ganglionic transmission was blocked, a marked vasoconstrictor effect of exendin‐4 was revealed in the mesenteric and hindquarters vascular beds (about 50% fall in vascular conductances). No role for endogenous angiotensin II, vasopressin, endothelin, neuropeptide Y or prostanoids could be shown in these vasoconstrictor actions of exendin‐4.Conclusions and implications: The results show not only an important involvement of the autonomic nervous system in the cardiovascular actions of exendin‐4 infusion but also an underlying non‐autonomically mediated vasoconstrictor action, the mechanism of which remains to be identified.
Effect of Intrapartum Antibiotic Prophylaxis Against Group B Streptococcal Infection on Comparisons of Rates of Endometritis and Urinary Tract Infection in Multicenter Surveillance
Authors: Dumas Anne-Marie , Girard Raphaëlle , Ayzac Louis , Beaumont Geneviève , Caillat-Vallet Emmanuelle , Depaix Florence , Gignoux Chantal , Haond Catherine , Pral Noelle , Robert Jacqueline , Tissot-Guerraz Françoise , Vincent-Bouletreau Agnès , Berland Michel , Fabry Jacques 
Published: March 2008

Objective.To establish whether antibiotic prophylaxis against group B streptococcal infection may be a confounding factor in comparisons of rates of endometritis and urinary tract infection after vaginal delivery.Design.Prospective study.Setting.Maternity units at 48 hospitals in a regional surveillance network in France during 2001-2004.Methods.The maternity units used a common protocol to establish whether antibiotic prophylaxis was indicated. Risk factors for endometritis and urinary tract infections were evaluated using multiple logistic regression.Results.We analyzed 49,786 vaginal deliveries. The percentage of women receiving antibiotic prophylaxis varied widely and significantly among the maternity units (range, 4.4%-26.0%; median, 15.8%; 25th percentile, 12.1%; 75th percentile, 19.0%) (P < .001, by Mantel-Haenszel χ2 test). The incidence rate of endometritis was significantly reduced from 0.25% to 0.11% by antibiotic prophylaxis (P = .001). There was a decrease in the incidence of urinary tract infection from 0.37% to 0.32%, but it was not statistically significant (P = .251).Conclusions.A reduction in the incidence of endometritis was observed when intrapartum antibiotic prophylaxis against group B streptococcal infection was used. However, the proportion of women considered to be at risk of infection varied widely among institutions. Comparisons of rates of endometritis among maternity units, but not urinary tract infection rates, should take into account antibiotic prophylaxis as a significant confounding factor.
Media for Mounting Fixed Cells on Microscope Slides
Authors: Fischer Andrew H. , Jacobson Kenneth A. , Rose Jack , Zeller Rolf 
Published: March 2008

INTRODUCTIONAfter a specimen is labeled, coverslips containing cells or tissues are mounted onto microscope slides, or slides containing sections are overlaid with a coverslip. A number of recipes for commonly used mounting media are presented in this article, each with particular recommendations.
Labeling Lysosomes in Live Cells with Fluorescent Dyes for Imaging
Authors: Chazotte Brad 
Published: March 2008

INTRODUCTIONThe eukaryotic cell has evolved to compartmentalize its functions and transport various metabolites among cellular compartments. Therefore, in cell biology, the study of organization and structure/function relationships is of great importance. Lysosomes are membranous sacs--diverse in shape and size--containing more than 40 different acid hydrolases. The enzymes operate optimally at the acidic pH (~5) within the lysosome to break down various substances. It is thought that the highly glycosylated nature of the proteins of the Golgi membrane helps to protect them from degradation. A number of the fluorescent approaches to visualizing lysosomes make use of their acidic pH. Commonly used probes include neutral red, N-(3-[2,4-dinitrophenyl amino] propyl)-N-(3-aminopropyl)methylamine (DAMP), and acridine orange (a DNA stain). This protocol describes the labeling of lysosomes in live cells with neutral red.
Culture of HEK293-EBNA1 Cells for Production of Recombinant Proteins
Authors: Tom Roseanne , Bisson Louis , Durocher Yves 
Published: March 2008

INTRODUCTIONFast and efficient production of recombinant proteins (r-proteins) remains a major challenge for the academic and biopharmaceutical communities. Pure r-proteins are often required in large amounts (hundreds of milligrams to gram quantities) when being developed as biotherapeutics, or in smaller quantities (milligrams) for high-throughput screening campaigns and structural or functional studies. Mammalian cells are often preferred over prokaryotic systems when expressing cDNAs of mammalian origin due to their superior capability to conduct elaborate post-translational modifications. Large-scale transfection of mammalian cells is now establishing itself as a “must-have” technology in the scientific community, as it allows the production of milligram to gram quantities of r-proteins within a few days after cDNA cloning into the appropriate expression vector. The HEK293 cell line stably expressing the Epstein-Barr virus nuclear antigen-1 (HEK293-EBNA1, or 293E) is the most commonly used cell line for large-scale transfection. When using expression vectors bearing the Epstein-Barr virus origin of replication, oriP (such as the pTT vector), a threefold improvement in r-protein yield is generally obtained over a similar non-oriP vector. This protocol describes a method for culturing HEK293-EBNA1 cells which will then be used to produce recombinant proteins.