bluuebunny/crossref_metadata_2025_split huggingface dataset:
Criteria for the assessment of analyser practicability
Authors: Biosca C. , Galimany R. 
Published: March 2007

This article lists the theoretical criteria that need to be considered to assess the practicability of an automatic analyser. Two essential sets of criteria should be taken into account when selecting an automatic analyser: ‘reliability’ and ‘practicability’. Practibility covers the features that provide information about the suitability of an analyser for specific working conditions.These practibility criteria are classsified in this article and include the environment; work organization; versatility and flexibility; safely controls; staff training; maintenance and operational costs.
Use of artificial intelligence in analytical systems for the clinical laboratory
Authors: Place John F. , Truchaud Alain , Ozawa Kyoichi , Pardue Harry , Schnipelsky Paul 
Published: March 2007

The incorporation of information‐processing technology into analytical systems in the form of standard computing software has recently been advanced by the introduction of artificial intelligence (AI), both as expert systems and as neural networks.This paper considers the role of software in system operation, control and automation, and attempts to define intelligence. AI is characterized by its ability to deal with incomplete and imprecise information and to accumulate knowledge. Expert systems, building on standard computing techniques, depend heavily on the domain experts and knowledge engineers that have programmed them to represent the real world. Neural networks are intended to emulate the pattern‐recognition and parallel processing capabilities of the human brain and are taught rather than programmed. The future may lie in a combination of the recognition ability of the neural network and the rationalization capability of the expert system.In the second part of the paper, examples are given of applications of AI in stand‐alone systems for knowledge engineering and medical diagnosis and in embedded systems for failure detection, image analysis, user interfacing, natural language processing, robotics and machine learning, as related to clinical laboratories.It is concluded that AI constitutes a collective form of intellectual propery, and that there is a need for better documentation, evaluation and regulation of the systems already being used in clinical laboratories.
Automation in the pharmaceutical analysis laboratory: a centralized/decentralizedapproach
Authors: Scypinski Stephen , Nelson Linda , Sadlowski Theodore 
Published: March 2007

It has been over 10 years since robots have appeared in the pharmaceutical analysis laboratory. In the early days, it was common for one selected individual to be responsible for the programming, usage and maintenance of the robots(s). However, the increasing use of robotics has prompted the formation of robotics
‘laboratories’ and/or ‘groups’. This is especially true when
multiple robotic systems and applications are involved.Over the past several years at ISLAR, many champions of robotics have given presentations on the setup and usage of robotics within their organizations. These managers have described both the ‘centralized’ and ‘decentralized’ approaches to the implementation of robotics. In the centralized system, a single group is charged with all aspects of the robotic project, including justification, purchase, validation, use and maintenance. Under such an
arrangement, samples are usually given to the robotics group for analysis. In contrast, a totally decentralized approach to robotics would have units interspersed throughout the organization, with each individual group responsible for their respective unit(s), in
much the same way as liquid chromatographs are considered.At Hoffmann‐La Roche, aspects of both the centralized and decentralized approaches to robotics are used which make our combined system the ‘best of both worlds’. This paper describes the Roche philosophy towards robotics and highlights the advantages to the system used.
Moving up the automation S‐curve: The role of the laboratory automation supportfunction in successful pharmaceutical R&D
Authors: Maddux Randy J. 
Published: March 2007

The political and economic climate that exists today is a challenging
one for the pharmaceutical industry. To effectively compete in today′s marketplace, companies must discover and develop truly innovative medicines. The R&D organizations within these companies are under increasing pressure to hold down costs while accomplishing this mission. In this environment of level head count and operating budgets, it is imperative that laboratory management uses resources in the most effective, efficient ways possible. Investment in laboratory automation is a proven tool for doing just that.This paper looks at the strategy and tactics behind the formation and evolution of a central automation/laboratory technology support function at the Glaxo Research Institute. Staffing of the function is explained, along with operating strategy and alignment with
the scientific client base. Using the S‐curve model of technological progress, both the realized and potential impact on successful R&D automation and laboratory technology development are assessed.
The electronic NOSE and its application to the manufacture of food products
Authors: Hodgins Diana , Sirnmonds Derek 
Published: March 2007

The Electronic NOSE (Neotronics Olfactory Sensing Equipment)
is an instrument which mimics the human olfactory sensory system.
It analyses complex vapours and produces a simple output. In the food industry there are numerous examples where the aroma from the raw ingredients through to the final product are important. These aromas are currently analysed using human sensory panels
or analytical equipment such as gas chromatography/mass spectroscopy (GC/MS).The Electronic NOSE described in this paper was not developed to replace the GC/MS or the sensory panel but to provide an instrumental measure of aroma quality which would be related to and complement the current methodology. The Electronic NOSE is a robust system which can detect complex vapours at levels similar to the human, which means typically in the parts per billion range. The system produces an output which can be easily related to sensory data and is easy to interpret by a non‐skilled operator. No part of this system reacts with the sample under test.
Automated colorimetric determination of recombinant fungal laccase activity in fermentation sarples using syringaldazine as chromogenic substrate
Authors: Holm K. A. , Nielsen D. M. , Eriksen J. 
Published: March 2007

An automated Cobas Fara method was developed determining the activity of recombinant M. thermophila laccase (rMtL). The chromogenic substrate used was syringaldazine. Under aerobic conditions, rMtL catalyses the oxidation of syringaldazine forming tetrametoxy‐azo bis methylene quinone. The developed violet colour was measured kinetically at 530 nm as an expression of the enzyme activity, rMtL is a very sensitive oxidoreductase, therefore many factors had to be carefully controlled in order to get a robust analytical assay. In order to stabilize rMtL, PEG 6000 was added to the enzyme dilution medium. Furthermore, Triton X‐I00 was included in the enzyme incubation solution.The analytical as well as technical conditions have been optimized, resulting in a method with good precision, sensitivity and speed of analysis. The Michaelis‐Menten constant, Km, was determined to be 22μM syringaldazine. LOQ was determined to be 0.010 Uml-1, LOD to be 0.0002 Uml-1 The analytical range of the enzyme dilution curve was from 0.01 to 0.044 Uml-1 The repeatability was 1.9%, the reproducibility 3.1%. Testing the robustness of the method showed that the most sensible factors in the rMtL analysis in decreasing range were: incubation temperature, concentration of Triton X‐I00, molarity and pH of the incubation buffer, and finally the concentration of syringaldazine.
Soluble plasma-derived von Willebrand factor assembles to a haemostatically active filamentous network
Authors: Barg Alexej , Ossig Rainer , Goerge Tobias , Schillers Hermann , Oberleithner Hans , Schneider Stefan , Schneider Matthias 
Published: March 2007

SummaryThe large glycoprotein vonWillebrand factor (VWF) is involved in the initial haemostatic reaction mediating the interaction between platelets and the injured vessel wall. It has been demonstrated that unusually large VWF (ULVWF) multimers after being released from endothelium are capable of developing elongated membrane-anchored strings that are hyperactive to bind platelets. In the present study we investigated whether soluble plasma-derived VWF is competent to develop similar thrombotically active multimers. We demonstrated that soluble VWF multimers isolated from human plasma self-assemble to a network of fibers immobilized on a collagen matrix and are functionally active to bind platelets. Formation of these VWF fibers depends on shear flow, concentration of solubleVWF, and a suitable binding surface. Self-assembly of soluble VWF does not require the presence of cellular membrane ligands. The network of fibers is subjected to rapid degradation by proteolytic activity of plasma ADAMTS-13.Atomic force microscopy images elucidate the nanostructure of VWF fibers and illustrate self-association and -aggregation of several filamentous multimers. Together, these results suggest that circulatingVWF can contribute to a formation of hyperactive VWF fibers on exposed subendothelial collagen during vascular injury.
Plasma membrane Ca2+-ATPase associates with CLP36, α-actinin and actin in human platelets
Authors: Bozulic Larry , Malik Mohammad , Powell David , Nanez Adrian , Link Andrew , Ramos Kenneth , Dean William 
Published: March 2007

SummaryThe plasma membrane Ca2+-ATPase (PMCA) plays an essentialrole in maintaining low cytosolic Ca2+ in resting platelets. Earlier studies demonstrated that the 4b isoform of PMCA interacts viaits C-terminal end with the PDZ domains of membrane-associated guanylate kinase proteins. Activation of saponin-permeabilized platelets in the presence of a peptide composed of the lastten residues of the PMCA4b C-terminus leads to a significant decrease of PMCA associated with the cytoskeleton, suggesting that PDZ domain interactions play a role in tethering the pumpto the cytoskeleton. Here we present experiments conducted to evaluate the mechanism of this association. Co-immunoprecipitationassays coupled with liquid chromatography/tandemmass spectrometry analysis and immunoblotting were used to identify proteins that interact with PMCA in the resting platelet. Our results indicate that the only PDZ domain-containing proteinassociated with PMCA is the LIM family protein, CLP36. Glutathione-S-transferase pull-down from a platelet extractusing a fusion protein containing the C-terminal PDZ domainbinding motif of PMCA confirmed binding of CLP36 to PMCA. Gel filtration chromatography of detergent-solubilized plateletsdemonstrated the existence of a 1,000-kDa complex containingPMCA and CLP36, and in addition, α -actinin and actin. Immunoflourescencemicroscopy confirmed the co-localization ofPMCA with CLP36 in resting and activated platelets. Taken togetherthese results suggest that PMCA is localized in non-filamentousactin complexes in resting platelets by means of PDZdomain interactions and then associates with the actin cytoskeletonduring cytoskeletal rearrangement upon platelet activation. Thus, in addition to the reversible serine/threonine andtyrosine phosphorylation events previously described in humanplatelets, PMCA function may be regulated by interactions withanchoring and cytoskeletal proteins.
Active endothelin is an important vasoconstrictor in acute coronary thrombi
Authors: Adlbrecht Christopher , Bonderman Diana , Plass Christian , Jakowitsch Johannes , Beran Gilbert , Sperker Wolfgang , Siostrzonek Peter , Glogar Dietmar , Maurer Gerald , Lang Irene 
Published: March 2007

SummaryAcute coronary syndrome is characterized by compromised blood flow at the epicardial and microvascular levels. We have previously shown that thrombectomy in ST-elevation myocardial infarction (STEMI) accelerates ST-segment resolution, possibly by preventing distal embolization. We hypothesized that thrombus constituents contribute to microcirculatory dysfunction. Therefore, we analyzed the molecular and cellular composition of acute coronary thrombi, and correlated vasoconstrictive mediators with the magnitude of ST-segment resolution within one hour of percutaneous coronary intervention (PCI). Fresh coronary thrombi were retrieved in 35 consecutive STEMI patients who were treated with the X-Sizer thrombectomy catheter, and thrombus cell counts and vasoconstrictor concentrations were assessed. Twelve-lead ECG recordings were analyzed prior to and one hour after PCI. Concentration of endothelin (ET) was 20.0 (7.9–52.2) fmol/ml in thrombus compared with 0.1 (0.1–0.3) fmol/ml in corresponding peripheral plasma (p<0.0001), representing a selective 280 (70.0–510.0)- fold enrichment, exceeding enrichment of noradrenaline, angiotensin II and serotonin. Human coronary thrombus homogenates exerted vasoconstriction of porcine coronary artery rings that was inhibited by the dual ET receptor blocker tezosentan. Extracted ET (r=0.523 p=0.026) and number of leukocytes (r=0.555 p=0.017) were correlated with the magnitude of STsegment resolution. In conclusion, the amount of active ET and white blood cells aspirated from STEMI target vessels correlated with improvement of territorial microcirculatory function as illustrated by enhanced ST-segment resolution.
Analysis of the novel factor X gene mutation Glu51Lys in two families with factor X-Riyadh anomaly
Authors: Wulff Karin , Abdel-Razeq Hikmat , Saud Khalida , Al-Gaili Fateh , Herrmann Falko , Al-Hilali Akram 
Published: March 2007

SummaryTwo families with 'factor X(FX)-Riyadh' have been identified (one of them related to the originally reported family). Affected members of both families exhibit prolongation in prothrombin time (PT) with normal partial thromboplastin time (PTT) and low assay levels of FX, when measured by PT-based assay. They do not have clinical bleeding diathesis, regardless of the PT prolongation. FX genes of the affected family members were analyzed by sequence analysis. A novel missense mutation in exon 4 of the FX gene, which causes the Glu51Lys substitution in the first epidermal growth factor-like domain of FX was found. The Glu51Lys mutation represents a type II mutation with low FX coagulant activity in the extrinsic pathway and normal FX antigen levels. This mutation may result in disruption of the predicted H-bonding between residue Glu51 of FX and the Asn199 residue of the tissue factor (TF) in the FX/TF/factorVIIa ternary complex, producing the phenotype 'FX deficiency Riyadh', with prolonged PT and normal PTT.
ABO blood group genotypes, plasma von Willebrand factor levels and loading of von Willebrand factor with A and B antigens
Authors: Morelli Vania , de Visser Marieke , van Tilburg Nico , Vos Hans , Eikenboom Jeroen , Rosendaal Frits , Bertina Rogier 
Published: March 2007

SummaryABO blood group is a genetic determinant of von Willebrand factor (VWF) levels. We investigated the effect of ABO genotypes on VWF and factor VIII (FVIII) levels and on the degree to which VWF is loaded with A- and B-antigens, expressed as normalized ratios, nA-ratio and nB-ratio, respectively, in the Leiden Thrombophilia Study, a large case-control study on venous thrombosis. We found that the ABO locus had an allele-specific, dosage dependent effect on VWF and FVIII levels and on the loading of VWF with A-antigen and B-antigen. The highest mean nA- and nB-ratios were found in A
1 A
1 and BB genotypes, respectively. Four A1 O carriers had four 43-bp repeats in the minisatellite region of theABO gene in stead of the expected one repeat. All had a reduced nA-ratio compared to A 1 O carriers with one repeat in their A1 allele. The amount of A – and B- antigens expressed onVWF (nA-ratio and nB-ratio) explained about 18% (R2) of the variation in VWF levels.
Critical temperature ranges of hypothermia-induced platelet activation: Possible implications for cooling patients in cardiac surgery
Authors: Breuer Melanie , Wendel Hans , Peter Karlheinz , Dietz Klaus , Ziemer Gerhard , Straub Andreas 
Published: March 2007

SummaryCooling of the patient is routinely applied in cardiac surgery to protect organs against ischemia. Hypothermia induces activation of platelets, but the effects of temperatures such as used during cardiac surgery are not well described. To investigate this in an in-vitro study heparinized whole blood was incubated at different temperatures (37°C, 34.5°C, 32°C, 29.5°C, 27°C, 24.5°C, 22°C, 19.5°C and 17°C).The effect of these temperatures on aggregation, P-selectin expression, GP IIb/IIIa activation and platelet microparticle (PMP) formation of unstimulated and ADP-stimulated platelets of 36 subjects was evaluated in flow cytometry. A four-parametric logistic model was fitted to depict the temperature effect on platelet parameters. Lower temperatures increased aggregates, P-selectin expression, and GP IIb/IIIa activation. The number of PMPs decreases with hypothermia. Additional experiments revealed a slight influence of heparin on platelet P-selectin expression but excluded an effect of this anticoagulant on the other evaluated parameters. Threshold temperatures, which mark 5% changes of platelet parameters compared to values at 37°C, were calculated. On ADP-stimulated platelets the thresholds for P-selectin expression and GP IIb/IIIa activation are 34.0°C and 36.4°C, respectively, and lie in the temperature range routinely applied in cardiac surgery. Hypothermia- induced platelet activation may develop in most patients undergoing cardiac surgery, possibly resulting in thromboembolic events, coagulation defects, and proinflammatory leukocyte bridging by P-selectin bearing platelets and PMPs. These findings suggest that pharmacological protection of platelets against hypothermia-induced damage may be beneficial during cardiac surgery.
The management of thrombosis in pregnancy: Role of low-molecular-weight heparin
Authors: Kher André , Nielsen Jorn , Bauersachs Rupert 
Published: March 2007

SummaryFatal pulmonary embolism remains the most common cause of mortality among pregnant women in many Western countries. The physiological changes of pregnancy produce a hypercoagulable state that increases the risk of venous thromboembolism (VTE).Women with inherited or acquired thrombophilias are at particularly high risk of VTE during pregnancy, and thromboprophylaxis may be advisable in some cases. Thrombophilia is also associated with complications of pregnancy, including fetal loss, pre-eclampsia, intra-uterine growth restriction, and placental abruption. The antithrombotic agents available for the prevention and treatment of VTE during pregnancy, and pregnancy complications, include unfractionated heparin (UFH), low-molecular-weight heparin (LMWH) and aspirin. Vitamin K antagonists are contra-indicated in pregnancy. Low-dose aspirin may have a role in the prevention of some pregnancy complications, although its safety in early and late pregnancy is uncertain. The efficacy and safety of LMWHs have been demonstrated for the prevention and treatment of VTE in pregnancy. These agents are increasingly being used in place of UFH, which is associated with a higher incidence of side effects compared with LMWH, in addition to the need for regular laboratory monitoring. Evidence is also emerging to support the use of LMWH in the prevention of recurrent fetal loss, although further trials are needed to explore the role of LMWHs in this indication and in the prevention of other complications of pregnacy.
Monocyte IL-10 produced in response to lipopolysaccharide modulates thrombin generation by inhibiting tissue factor expression and release of active tissue factor-bound microparticles
Authors: Poitevin Stéphane , Cochery-Nouvellon Eva , Dupont Annick , Nguyen Philippe 
Published: March 2007

SummaryLipopolysaccharide (LPS)-stimulated monocytes are known to have a procoagulant effect. This property is currently explained by the fact that monocytes, in response to LPS, can express tissue factor (TF) and undergo a process of membrane microvesiculation. Interleukin-10 (IL-10) has been shown to downregulate TF expression and inhibit procoagulant activity (PCA). In order to further characterize the inhibitory effect of IL-10 on LPS-induced PCA, we used the integrated system of analysis of kinetics of thrombin generation in normal plasma (thrombinography). For this, we developed an original method of elutriation allowing to obtain a highly purified monocyte preparation, under endotoxin-free conditions. Thrombin generation was measured using a highly sensitive and specific fluorogenic method which we adapted to inhibit the contact factor pathway. Results show that recombinant human IL-10 decreased the kinetics of thrombin generation in a dose-dependent manner. Furthermore, the inhibition of endogenous IL-10 released by monocytes in response to LPS is associated with an increase in the kinetics of thrombin generation. We demonstrated that this effect was a consequence of the up-regulation of TF expression and TF-bound microparticle release. In conclusion, we report that IL-10 can regulate thrombin generation in conditions close to physiology as allowed by thrombinography, and that endogenous IL-10 regulates TF expression and release of active TF-bound microparticles by a negative feed back loop through IL-10 receptor α
Fibronectin-binding proteins and clumping factor A in Staphylococcus aureus experimental endocarditis: FnBPA is sufficient to activate human endothelial cells
Authors: Heying Ruth , Gevel Joke , Que Yok-Ai , Moreillon Philippe , Beekhuizen Henry 
Published: March 2007

SummarySurface molecules of Staphylococcus aureus are involved in the colonization of vascular endothelium which is a crucial primary event in the pathogenesis of infective endocarditis (IE).The ability of these molecules to also launch endothelial procoagulant and proinflammatory responses, which characterize IE, is not known. In the present study we investigated the individual capacities of three prominent S. aureus surface molecules; fibronectinbinding protein A (FnBPA) and B (FnBPB) and clumping factor A (ClfA), to promote bacterial adherence to cultured human endothelial cells (ECs) and to activate phenotypic and functional changes in these ECs. Non-invasive surrogate bacterium Lactococcus lactis, which, by gene transfer, expressed staphylococcal FnBPA, FnBPB or ClfA molecules were used. Infection of ECs increased 50- to 100-fold with FnBPA- or FnBPB-positive recombinant lactococci. This coincided with EC activation, interleukin- 8 secretion and surface expression of ICAM-1 andVCAM-1 and concomitant monocyte adhesion. Infection with ClfA-positive lactococci did not activate EC. FnBPA-positive L. lactis also induced a prominent tissue factor-dependent endothelial coagulation response that was intensified by cell-bound monocytes. Thus S. aureus FnBPs, but not ClfA, confer invasiveness and pathogenicity to non-pathogenic L. lactis organisms indicating that bacterium-EC interactions mediated by these adhesins are sufficient to evoke inflammation as well as procoagulant activity at infected endovascular sites.