bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preoperative Values of Molecular Coagulation Markers Identify Patients at Low Risk for Intraoperative Haemostatic Disorders and Excessive Blood Loss
Authors: Korte Wolfgang , Truttmann Berta , Heim Christoph , Stangl Ulrike , Schmid Luzius , Kreienbühl Georg 
Published: October 2004

Abstract
Conventional laboratory investigations of haemostasis like prothrombin time and activated partial thromboplastin time are not useful in predicting and managing intra-operative bleeding complications. In order to establish a possible “perioperative reference range” for thrombin generation prothrombin fragment F1+2 (F1+2) and fibrin degradation (D-dimer) markers, we measured F1+2 and D-dimer concentrations before surgery (but after induction of anaesthesia), 30 minutes into surgery, 10 minutes after the event expected to induce the maximal activation of the haemostatic systems, 90 minutes after surgery and on postoperative days 1 and 2 in 226 consecutive patients. Samples were collected from arterial lines. Twenty patients developed a clinically defined, intraoperative disorder of haemostasis, 206 did not. Patients with an intraoperative disorder of haemostasis had significantly higher preoperative F1+2 and D-dimer concentrations. Preoperative values for F1+2 and D-dimer concentrations above the 75th percentile of patients without an intraoperative disorder of haemostasis indicated a 2.70 to 2.88 fold risk of developing an intraoperative disorder of haemostasis (odds ratios were 3.04, 3.12 and 3.29 for D-dimer, ELISA, F1+2, and D-dimer latex tests, respectively with 95% confidence intervals from 1.20 to 8.46) with negative predictive values of 94%, but positive predictive values of only 16% to 26%. These data suggest that preoperative determination of molecular markers might be helpful in identifying a group of patients at high risk for intraoperative disorder of haemostasis by exclusion of low risk patients. Validation of such an approach requires a prospective trial.
Rifampicin Causes False-Positive Immunoassay Results for Urine Opiates
Authors: de Paula Marta , Saiz Luis C. , González-Revaldería Joaquín , Pascual Tomás , Alberola Carmen , Miravalles Elena 
Published: October 2004

Abstract
The treatment of tuberculosis usually includes the antibiotic rifampicin, especially in patients with concomitant human immunodeficiency virus infection. Some of these patients are in withdrawal therapy for drug abuse. When opiate screening is carried out in patients receiving rifampicin, false positive results are detected with the kinetic interaction of microparticles in solution method. We evaluated this interference in a Cobas-Integra analyzer and found a 12% cross-reactivity of rifampicin for antibiotic concentrations ranging from 0.19 to 6.08 μmol/l (156 to 5000 μg/l). This effect is not explained by the colour of the rifampicin solutions. Calculations assuming first order kinetics of elimination show that more than 18 hours after a single oral dose of 600 mg of rifampicin, a false positive result for opiates could be obtained. This indicates that the risk of a false positive result must always be considered when urine samples from these patients are analyzed.
Mutation Analysis of Exon 3 of the LDL Receptor Gene in Patients with Severe Hypercholesterolemia
Authors: Geisel Jürgen , Gielen Jörg , Oette Kurt , Herrmann Wolfgang , Wielckens Klaus 
Published: October 2004

Abstract
Single-strand conformation polymorphism analysis was used to screen for mutations in exon 3 of the low density lipoprotein receptor gene in a group of 218 unrelated patients with severe hypercholesterolemia (low density lipoprotein cholesterol > 6.7 mmol/l) living in the Cologne area of Germany. Including the complementary primers the fragment studied had a length of 176 bp. An abnormal single-strand conformation polymorphism pattern was observed in eight patients, four of whom had an identical abnormal fragment pattern indicating that five different mutations were present. By direct DNA sequencing, the underlying mutations could be confirmed (Cys54→Tyr, Trp66→Gly, Glu80→Lys, 2 bp insertion (AT between codon 44 and 45, 9 bp deletion (codons 65 to 67)). The analysis of the pathogenicity indicates that all mutations were causative for the low density lipoprotein cholesterol elevation. The Trp66→Gly and Glu80→Lys mutations were previously described in a French-Canadian population and in an English population, respectively. The 2 bp insertion was detected in four unrelated patients and is one of the most frequent mutations detected up to now in the German population.
Long-Term Variability of Serum Lipoprotein(a) Concentrations in Healthy Fertile Women
Authors: Garnotel Roselyne , Monier Frédérique , Lefèvre Fabrice , Gillery Philippe 
Published: October 2004

Abstract
Lipoprotein(a) is a unique lipoprotein with atherothrombogenic properties. Although its blood concentration is mainly genetically determined, various factors exist which may cause variability. These may influence the clinical use of the results. We studied lipoprotein(a) biological variation by a rate nephelometric assay over a period of two years in a population of healthy fertile women. The study was performed in 12 volunteers, healthy subjects with various lipoprotein( a) concentrations, by monthly determinations during one year and a single determination one year later, together with measurements of total, high density lipoprotein and high density lipoprotein2 cholesterol, triglycerides and apolipoproteins A1 and B. The intra-individual variability of lipoprotein(a) ranged between 4 to 20%, with three subjects showing a coefficient of biological variation higher than 15 %. In absolute terms, the difference between two determinations could represent 0.44 g/l or 50 % of the mean value. This study suggests that physiological lipoprotein( a) variations should be taken into account for clinical purposes, especially in patients in need of thorough risk evaluation.
Standardization of Steroid Immunoassays – In Theory an Easy Task
Authors: Thienpont Linda M. 
Published: October 2004

Abstract
I deal with the process of standardization of steroid
immunoassays on the basis of metrological traceability (SI units). First, I
discuss the role theoretically attributed to the calibration of the measurement
procedure. Since immunoassays show matrix sensitivity, I associate traceability
of calibration with traceability of results pertaining to individual patient
samples. From this, I stress that optimization of the immunoassays in terms of
specificity and insensitivity to different kinds of interference is necessary
before standardization, and that split-sample measurements should be included in
the standardization process. Last but not least, I give an overview of the
current status of standardization of steroid immunoassays.
Thermodynamic Parameters in Immunoassay
Authors: Regenmortel Marc H. V. Van 
Published: October 2004

Abstract
Although affinity and kinetic measurements on their own
provide useful information regarding the suitability of antibodies for various
immunoassays, a thermodynamic analysis provices additional information that
throws light on the molecular forces at work in the antigen-antibody
interaction. It may then be possible to adjust assay conditions in order to
favour either the association or dissociation of antigen-antibody complexes. A
tenfold increase in binding affinity (K) corresponds to a free energy change of
only 1.4 kcal/mol (5.8 kJ/mol) at 25 °C. This means that K values of
105 M−1 and 1010 M−1 correspond to a
free energy change (∆G) of 7.0 and 14.0 kcal/mol respectively. The entire range
of affinity constants normally encountered in antigen-antibody interactions,
therefore differs by no more than about 7 kcal/mol of free energy change, which
is equivalent to only a few hydrogen bonds. In comparison, a single
electrostatic interaction corresponds to about 4 kcal/mol of free energy change.
A full description of the binding interaction requires an understanding of the
change in hydration states of the reactants when the complex forms, and an
assessment of the entropic andenthalpic effects of these changes. Contrary to
earlier assumptions, it is now clear that antigen-antibody interactions are
often accompanied by a large favourable enthalpy which more than compensates the
unfavourable entropy.
Antigenic Definition of Cardiac Troponin I
Authors: Larue Catherine , Ferrieres Gaëlle , Laprade Michel , Calzolari Charles , Granier Claude 
Published: October 2004

Abstract
The presence of cardiac troponin I in the serum is now
considered as one of the most specific biochemical markers of acute myocardial
infarction. To improve the knowledge of the antigenic properties of cardiac
Troponin I, a set of monoclonal antibodies and polyclonal antibodies against
human cardiac troponin I has been tested with overlapping peptides covering the
cardiac troponin I sequence. The results indicate that N-terminal and C-terminal
cardiac troponin I regions were most often recognized by poly- and monoclonal
antibodies. These observations are valuable for choosing the best combination of
monoclonal antibodies to set up new immunoassays to detect serum cardiac
troponin I earlier after myocardial damage, to understand better which forms are
released, and finally to propose appropriate cardiac troponin I standards.
Rapid Electrophoretic Separation of Pre-ß-Migrating High Density Lipoproteins Using Automated PhastSystem(tm): Application to Analysis of Lecitihin: Cholesterol Acyltransferase-Deficient Plasma
Authors: Saïdi Youssef , Sich Didier , Federspiel Marie-Christine , Auer Claude , Egloff Monique , Castro Gracielo R. , Beucler Isabel 
Published: October 2004

Abstract
To identify pre-β-high density lipoproteins, a rapid
two-dimensional separation by electrophoresis (1 hour 30 minutes) was performed
on an automated Phast System™. This procedure used commercially available
polyacrylamide gradient gels (4–15 %) and allows sensitive and reproducible
results. Pre-β-1- and pre-β-2-high density lipoproteins were clearly identified
by this method. In addition, our procedure was successfully applied to diagnosis
of a patient with familial lecithin: cholesterol acyltransferase deficiency,
characterized by the absence of α-high density lipoproteins.
Cytokines and Soluble Adhesion Molecules in Laboratory Diagnostics. Report from a Meeting Held at the German Cancer Research Center in Heidelberg on 25 November 1997
Authors: Bertsch Thomas , Richter Axel 
Published: October 2004

AbstractCytokines and soluble adhesion molecules play an increasing role in laboratory medicine especially due to the increasing knowledge of the function of the immune system and the availability of cytokine assays on analyzers working in the "random-access" mode. This meeting report gives an insight of different applications for the measurements of these immunomediators. Examples from surgery, pediatrics, transplantation medicine and immunopharmacology show that these parameters could provide early and useful information for diagnosis, prognosis, therapeutic decision making and drug actions.
Will humans swim faster or slower in syrup?
Authors: Gettelfinger Brian , Cussler E. L. 
Published: October 2004

AbstractForewordThe scientific and engineering principles that underlie chemical engineering can also be used to understand a wide variety of other phenomena, including in areas not thought of as being central to our profession. As such applications might be of interest to our readers, we will consider brief submissions for publication in this category as R&D notes. These submissions will undergo review, and novelty will be an important factor in reaching an editorial decision.The first such article, “Will Humans Swim Faster or Slower in Syrup?” by Brian Gettelfinger and associate editor Ed Cussler, appears in this issue. Stanley I. Sandler Editor
Within‐group social relationships among females and adult males in wild western lowland gorillas (Gorilla gorilla gorilla)
Authors: Stokes Emma J. 
Published: October 2004

AbstractWithin‐group female relationships, and relationships between females and adult males have not been described for wild western lowland gorillas. New data are presented here from Mbeli Bai in the Nouabalé‐Ndoki National Park, Republic of Congo. Nine groups were observed over a continuous 2‐year period, and affiliative and agonistic interactions, as well as time spent by females and adult males in proximity to each other were recorded. Affiliative behavior was extremely rare in the bai, and measures of proximity between individuals were inconclusive because of the small sample sizes. Rates of agonistic interaction among females were highly variable between groups. The majority of agonistic interactions were undecided, and the supplant rate was low. Evidence for an agonistic dominance hierarchy is weak. The data do not support hypotheses that increased frugivory in western lowland gorillas raises levels of within‐group contest competition; however, the need for intersite comparisons is stressed. In contrast, rates of agonistic behavior between females and silverback males were higher and more consistent between groups. Agonistic relationships between males and females conformed with patterns seen in mountain gorillas, where male protection from intraspecific aggression is important. The benefit females gain by forming long‐term cooperative alliances appears to be small, and is likely outweighed by reproductive advantages associated with male protection. Am. J. Primatol. 64:233–246, 2004. © 2004 Wiley‐Liss, Inc.
Rheological study of poly(ethylene glycol)/poly(N‐isopropylacrylamide‐co‐2‐acrylamido‐2‐methylpropanesulphonic acid) semiinterpenetrating network formation
Authors: Zhang Chi , Easteal Allan J. 
Published: October 2004

AbstractThe formation of a series of semiinterpenetrating network (SIPN) hydrogels made by free‐radical copolymerization of N‐isopropylacrylamide (NIPA) and 2‐acrylamido‐2‐methylpropanesulphonic acid (AMPS) with varying comonomer mole ratios, crosslinked with N,N′‐methylene‐bisacrylamide (MBAA) in the presence of poly(ethylene glycol) (PEG) with average molecular weight 6,000 g mol−1 was studied via determination of complex viscosity, η*, using plate–plate rheometry. The isothermal time dependence of η* at various temperatures or the variation of η* with temperature of pregel solutions was utilized to detect the onset of gelation. The SIPN systems were compared with the corresponding gels made under the same conditions in the absence of PEG. The copolymer mainchain composition has a major effect on the time or temperature for onset of gelation and in particular gelation appears to be inhibited to some extent by MBAA when the AMPS/NIPA mole ratio in the pregel solution exceeds 0.5. The presence or absence of PEG in pregel solutions has a lesser effect on gelation. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2083–2087, 2004
Imparting affinity sites for adenosine triphosphate on the surface of polyurethane through molecular imprinting
Authors: Sreenivasan K. 
Published: October 2004

AbstractA simple methodology for imparting affinity sites for adenosine triphosphate (ATP) on the surface of polyurethane (PU) film is discussed. It is widely known that, through oxidation, a thin layer conjugated polymer can be coated onto many polymeric substrates. This possibility is explored in this report. 3‐Amino phenyl boronic acid was polymerized in the presence of ATP as template using ammonium per sulfate. A thin layer of polyamino phenyl boronic acid was coated onto the surface of PU film immersed in the solution during the reaction. The coated layer showed remarkably high affinity toward ATP and equilibrium adsorption was attained rapidly in contrast to free standing molecularly imprinted polymers in which equilibrium adsorption is normally attained after several hours. The imprinted layer also showed a high degree of selectivity toward ATP compared to adenosine diphosphate (ADP). The approach is simple and affinity sites for any water soluble molecules can virtually be created on the surface of polymers of interest. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2088–2090, 2004
Polyimides containing 4,4′‐bipyridinium units
Authors: Gaina C. , Gaina V. , Airinei A. , Avram E. 
Published: October 2004

AbstractNew polyimides containing 4,4′‐bipyridinium units were synthesized by the reaction of bis(dichloromaleimide)arylene derivatives with 4,4′‐bipyridine in meta‐cresol. IR and 1H‐NMR spectroscopy and elemental analysis as well confirmed their structures. The polymers were characterized by viscometric measurements, softening points, and thermogravimetric data. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2091–2100, 2004
Pervaporation separation of water–acetic acid mixtures through NaY zeolite‐incorporated sodium alginate membranes
Authors: Kittur A. A. , Tambe S. M. , Kulkarni S. S. , Kariduraganavar M. Y. 
Published: October 2004

AbstractThe pervaporation (PV) separation and swelling behavior of water–acetic acid mixtures were investigated at 30, 40, and 50°C using pure sodium alginate and its zeolite‐incorporated membranes. The effects of zeolite loading and feed composition on the pervaporation performance of the membranes were analyzed. Both the permeation flux and selectivity increased simultaneously with increasing zeolite content in the polymer matrix. This was discussed on the basis of a significant enhancement of hydrophilicity, selective adsorption, and molecular sieving action, including a reduction of pore size of the membrane matrix. The membrane containing 30 mass % of zeolite showed the highest separation selectivity of 42.29 with a flux of 3.80 × 10−2 kg m−2 h−1 at 30°C for 5 mass % of water in the feed. From the temperature dependency of diffusion and permeation data, the Arrhenius activation parameters were estimated. The Ep and ED values ranged between 72.28 and 78.16, and 70.95 and 77.38 kJ/mol, respectively. The almost equal magnitude obtained in Ep and ED values signified that both permeation and diffusion contribute equally to the PV process. All the membranes exhibited positive ΔHs values, suggesting that the heat of sorption is dominated by Henry's mode of sorption. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2101–2109, 2004
Rheological and mechanical properties of compatibilized polystyrene/ethylene vinyl acetate blends
Authors: Tang L. W. , Tam K. C. , Yue C. Y. , Hu X. , Lam Y. C. , Li L. 
Published: October 2004

AbstractIn this study, a blend of polystyrene (PS)/ethylene vinyl acetate (EVA) (PS/EVA, 90 : 10 wt %) was compatibilized with three different block copolymers, in which their end blocks were compatible with either styrene or EVA. The compatibilized blends with different compositions were prepared using a twin‐screw extruder and injection molded into the required test specimens. Mechanical properties of the blends, such as tensile properties and Charpy impact strength, morphology of tensile fractured surfaces, rheological properties, and thermal properties, were investigated. The results show that the interaction between the dispersed and continuous phase can be improved by the addition of a compatibilizer. Appreciable improvement in the impact strength of the blend with 15 wt % of compatibilizer C (polystyrene‐block‐polybutadiene) was observed. Its mechanical properties are comparable to those of the commercial high‐impact polystyrene, STYRON 470. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2071–2082, 2004
Effect of molecular chain structure of the cured epoxy resin containing hyperbranched (3‐hydroxyphenyl) phosphate on expansion and flame retardance
Authors: Deng Jing , Zhu Shengwu , Shi Wenfang 
Published: October 2004

AbstractMelamine is widely used as a blowing agent in intumescent flame‐retardant systems. However, when it was blended into the epoxy resin cured with hyperbranched (3‐hydroxyphenyl) phosphate (HHPP), neither greater expansion nor improved limiting oxygen index (LOI) was obtained during combustion compared with that without melamine addition. When a portion of HHPP was replaced by polyethylene glycol (PEG), both the expansion degree and the LOI increased, along with the content of PEG, even if the same amount of melamine was blended. This phenomenon shows that the molecular chain structure of the cured epoxy resin based on HHPP has a substantial effect on the flame retardance. Only when the degraded products are sufficiently viscous, at the decomposition temperature of the blowing agent, can the material be bubbled to form an expanding charred crust. The morphologic structure of the crust of the epoxy resin cured with HHPP shows that there were many holes on the surface because the degraded products were too rigid to be bubbled, from which the gases formed by melamine evolved. With increasing PEG content, the degraded products became increasingly viscous and bulged more easily with the gases. No holes appeared on the charred crust of the sample cured with the mixture of HHPP and PEG at a ratio of 3:1. In this case, most of the gases were entrapped and caused the material to expand, resulting in the increases of expansion degree and LOI. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2065–2070, 2004
Effect of vibration on crystal morphology and structure of isotactic polypropylene in nonisothermal crystallization
Authors: Zheng Qiang , Shangguan Yonggang , Tong Lifang , Peng Mao 
Published: October 2004

AbstractAn experimental study on crystal structure and morphology of isotactic polypropylene (iPP) subjected to vibration was carried out on a laboratory apparatus. Crystallite size, crystal structure, and crystallinity of iPP under vibration or nonvibration were investigated through differential scanning calorimeter (DSC), wide angle X‐ray diffraction (WAXD), and polarized optical microscopy (POM). The results reveal that at high cooling rate, the crystallinity of samples under vibration decreases, and at low cooling rate it remains constant because of chain relaxation. On the other hand, the sizes of the iPP spherulites under vibration decrease as compared with those without vibration. Taking the relaxation of the iPP chain into consideration, we believe that the influence of vibration conditions on the main α‐form of the iPP crystal is rather complex. An obvious increase of β‐form content in the crystal phase results from the imposition of vibration. The results indicate that the content of β‐iPP is dependent on vibration amplitude and time. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2187–2195, 2004
Isothermal crystallization kinetics and melting behavior of nylon/saponite and nylon/montmorillonite nanocomposites
Authors: Wu Tzong‐Ming , Lien Yi‐Hsin , Hsu Sung‐Fu 
Published: October 2004

AbstractDSC thermal analysis and X‐ray diffraction have been used to investigate the isothermal crystallization behavior and crystalline structure of nylon 6/clay nanocomposites. Nylon 6/clay has prepared by the intercalation of ε‐caprolactam and then exfoliating the layered silicates by subsequent polymerization. The DSC isothermal results reveal that introducing saponite into the nylon structure causes strongly heterogeneous nucleation induced change of the crystal growth process from a two‐dimensional crystal growth to a three dimensional spherulitic growth. But the crystal growth mechanism of nylon/montmorillonite nanocomposites is a mixed two‐dimensional and three‐dimensional spherulitic growth. The activation energy drastically decreases with the presence of 2.5 wt % clay in nylon/clay nanocomposites and then slightly increases with increasing clay content. The result indicates that the addition of clay into nylon induces the heterogeneous nucleation (a lower ΔE) at lower clay content and then reduces the transportation ability of polymer chains during crystallization processes at higher clay content (a higher ΔE). The correlation among crystallization kinetics, melting behavior, and crystalline structure of nylon/clay nanocomposites is also discussed. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2196–2204, 2004