30 research outputs found

    Very low intraspecific sequence variation in selected nuclear and mitochondrial Parascaris univalens genes

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    45 p.-4 fig.Equines were over decades considered to be infected by two morphologically virtually indistinguishable ascarid species, Parascaris univalens and Parascaris equorum. Reliable species discrimination is only possible using enzyme isoelectric focussing and karyotyping with P. univalens having one and P. equorum two chromosome pairs. However, presumably the complexity of both methods prevented their routine use in nearly all previous studies about prevalence and drug resistance of Parascaris spp. These have barely been performed on the species level although most studies stated presence of one or the other species. Recently, only P. univalens has been identified by karyotyping and the last published study identifying P. equorum dates back to 1989. In order to improve species-specific detection, molecular markers are required. Here, partial 12S rRNA, cytochrome oxidase I (COI) and complete internal transcribed spacer (ITS)-1 and - 2 sequences were obtained from 24 karyotyped Parascaris specimens from Poland and 6 German specimens (not karyotyped) and used in phylogenetic analyses with orthologous sequences from GenBank. All karyotyped specimens were identified as P. univalens. In the phylogenetic analysis, they formed very homogenous clusters for all target genes and in a multi-locus analysis. Within this cluster, almost all sequences from GenBank were also included, no matter if they had been assigned to P. univalens or P. equorum. However, a small number of P. univalens ITS and COI sequences originating from donkeys from a single farm in China formed a highly supported sister cluster suggesting that they might represent another Parascaris genotype or species. Our data also strongly suggest that nearly all ITS and COI sequences previously deposited in GenBank and assigned to P. equorum actually represent P. univalens. The fact that significantly different sequences can be found in Parascaris spp. suggests that PCR-based species diagnosis will be possible once molecular markers have been identified for P. equorum from karyotyped specimens.The funding of this study by the Deutsche Forschungsgemeinschaft (DFG, project number 111144555) is thankfully acknowledgedPeer reviewe

    New Synthetic Thrombin Inhibitors: Molecular Design and Experimental Verification

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    BACKGROUND: The development of new anticoagulants is an important goal for the improvement of thromboses treatments. OBJECTIVES: The design, synthesis and experimental testing of new safe and effective small molecule direct thrombin inhibitors for intravenous administration. METHODS: Computer-aided molecular design of new thrombin inhibitors was performed using our original docking program SOL, which is based on the genetic algorithm of global energy minimization in the framework of a Merck Molecular Force Field. This program takes into account the effects of solvent. The designed molecules with the best scoring functions (calculated binding energies) were synthesized and their thrombin inhibitory activity evaluated experimentally in vitro using a chromogenic substrate in a buffer system and using a thrombin generation test in isolated plasma and in vivo using the newly developed model of hemodilution-induced hypercoagulation in rats. The acute toxicities of the most promising new thrombin inhibitors were evaluated in mice, and their stabilities in aqueous solutions were measured. RESULTS: New compounds that are both effective direct thrombin inhibitors (the best K(I) was <1 nM) and strong anticoagulants in plasma (an IC(50) in the thrombin generation assay of approximately 100 nM) were discovered. These compounds contain one of the following new residues as the basic fragment: isothiuronium, 4-aminopyridinium, or 2-aminothiazolinium. LD(50) values for the best new inhibitors ranged from 166.7 to >1111.1 mg/kg. A plasma-substituting solution supplemented with one of the new inhibitors prevented hypercoagulation in the rat model of hemodilution-induced hypercoagulation. Activities of the best new inhibitors in physiological saline (1 µM solutions) were stable after sterilization by autoclaving, and the inhibitors remained stable at long-term storage over more than 1.5 years at room temperature and at 4°C. CONCLUSIONS: The high efficacy, stability and low acute toxicity reveal that the inhibitors that were developed may be promising for potential medical applications

    ADAM2 Interactions with Mouse Eggs and Cell Lines Expressing α4/α9 (ITGA4/ITGA9) Integrins: Implications for Integrin-Based Adhesion and Fertilization

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    Integrins are heterodimeric cell adhesion molecules, with 18 α (ITGA) and eight β (ITGB) subunits forming 24 heterodimers classified into five families. Certain integrins, especially the α(4)/α(9) (ITGA4/ITGA9) family, interact with members of the ADAM (a disintegrin and metalloprotease) family. ADAM2 is among the better characterized and also of interest because of its role in sperm function. Having shown that ITGA9 on mouse eggs participates in mouse sperm-egg interactions, we sought to characterize ITGA4/ITGA9-ADAM2 interactions.An anti-β(1)/ITGB1 function-blocking antibody that reduces sperm-egg binding significantly inhibited ADAM2 binding to mouse eggs. Analysis of integrin subunit expression indicates that mouse eggs could express at least ten different integrins, five in the RGD-binding family, two in the laminin-binding family, two in the collagen-binding family, and ITGA9-ITGB1. Adhesion assays to characterize ADAM2 interactions with ITGA4/ITGA9 family members produced the surprising result that RPMI 8866 cell adhesion to ADAM2 was inhibited by an anti-ITGA9 antibody, noteworthy because ITGA9 has only been reported to dimerize with ITGB1, and RPMI 8866 cells lack detectable ITGB1. Antibody and siRNA studies demonstrate that ITGB7 is the β subunit contributing to RPMI 8866 adhesion to ADAM2.These data indicate that a novel integrin α-β combination, ITGA9-ITGB7 (α(9)β(7)), in RPMI 8866 cells functions as a binding partner for ADAM2. ITGA9 had previously only been reported to dimerize with ITGB1. Although ITGA9-ITGB7 is unlikely to be a widely expressed integrin and appears to be the result of "compensatory dimerization" occurring in the context of little/no ITGB1 expression, the data indicate that ITGA9-ITGB7 functions as an ADAM binding partner in certain cellular contexts, with implications for mammalian fertilization and integrin function

    Risk assessement in multi-project environment

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    Decision making supported by task-oriented software tools plays a pivotal role in a modern enterprise. That is because commercially available ERP systems are not able to respond in an interactive on-line/real-time mode. It opens a new generation of DSS that enable a fast prototyping of production flows in multi-project environment as well as an integrated approach to project execution evaluation. In that context our goal is to provide a knowledge base approach allowing one to be independent on a context or representation of particular data as well as allowing designing an interactive and task-oriented decision support system (DSS). The assumed knowledge base mode of specifying a production system leads to solving a logic-algebraic method (LAM) decision problem. The approach proposed complements the decision system with an additional module (evaluation module) and facilitates searching for possible solutions meeting company production programme execution evaluation criteria. The results obtained are implemented in a software package supporting project management in the SMEs. Illustrative example of the ILOG-based software application is provided

    CP-based decision support package for production flow planning - an SME perspective

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    Solving complex, decision-making problems requires application of decision support systems. The best solving strategy can be defined for each particular problem. The strategy refers to a sequence solving elementary subproblems. The aim of the paper is to present the evaluating criterion to estimate the efficiency of searching strategies. The criterion proposed offers a possibility to estimate the time needed to solve a constraint satisfaction problem. An illustrative example is provided

    Towards CLP-based task-oriented DSS for SME

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    Decision making supported by task-oriented software tools plays a pivotal role in a modern enterprises. That is because commercially available ERP systems are not able to respond in an interactive on-line/real-time mode. It means a new generation of DSS that enable a fast prototyping of production flows in multiproject environment as well as an integrated approach to a layout planning, production routing, batch-sizing and scheduling problems is needed. In that context, the constraint logic programming techniques allowing declarative representation of a decision making problem provide a quite attractive alternative. So, some issues regarding modelling of decision making and searching strategies development are discussed in the contribution. The results obtained are implemented in a software package supporting production flow planning in the SMEs. Illustrative example of the ILOG-based software application is provided

    Comparative analysis and assessment of the monitor display for the selected station of management and rail traffic control system in terms of ergonomic

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    W artykule przedstawiono próbę wykonania analizy porównawczej oraz oceny elementów monitorowego zobrazowania na wybranym, rzeczywistym stanowisku sterowania i kierowania ruchem kolejowym obsługiwanym przez dyżurnego ruchu wykorzystującego pulpit elektroniczny, w ujęciu ergonomicznym. Badanie własne przeprowadzono na rzeczywistym systemie, realizującym zobrazowanie zgodnie z wytycznymi PKP Polskie Linie Kolejowe S.A. Analizie poddano monitorowe zobrazowanie stanowiące interfejs do systemów sterowania i kierowania ruchem kilku firm produkujących dla potrzeb PKP Polskie Linie Kolejowe S.A. Wyniki przeprowadzonych badań oraz wyciągnięte na ich podstawie wnioski potwierdzają osiągnięcie przyjętych celów badawczych i są podstawą do dalszego analizowania tematu poruszonego w artykule.An attempt to perform a comparative analysis and evaluation of visualization components at a selected, real control and traffic control station operated by on-call traffic using an electronic desktop, in an ergonomic setting have been undertaken in this article. Own study was carried out on the real system, rendering the image according to PKP Polskie Linie Kolejowe S.A. The analysis was monitored by displaying the interface to the control and traffic control system of several companies producing for the needs of PKP Polskie Linie Kolejowe S.A. The results of the research and the conclusions drawn from them confirm the attainment of the accepted research objectives and have been the basis for further analysis of the topic addressed in the article
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