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1.
Renner S Ludwig V Boden O Scheffer U Göbel M Schneider G 《Chembiochem : a European journal of chemical biology》2005,6(6):1119-1125
TAR RNA is a potential target for AIDS therapy. Ligand-based virtual screening was performed to retrieve novel scaffolds for RNA-binding molecules capable of inhibiting the Tat-TAR interaction, which is essential for HIV replication. We used a "fuzzy" pharmacophore approach (SQUID) and an alignment-free pharmacophore method (CATS3D) to carry out virtual screening of a vendor database of small molecules and to perform "scaffold-hopping". A small subset of 19 candidate molecules were experimentally tested for TAR RNA binding in a fluorescence resonance energy transfer (FRET) assay. Both methods retrieved molecules that exhibited activities comparable to those of the reference molecules acetylpromazine and chlorpromazine, with the best molecule showing ten times better binding behavior (IC50 = 46 microM). The hits had molecular scaffolds different from those of the reference molecules. 相似文献
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M. Shamim Hossain Sandro Hardy Atif Alamri Abdulhameed Alelaiwi Verena Hardy Christoph Wilhelm 《Multimedia Systems》2016,22(6):659-674
Stroke is considered one of the main causes of death around the world. Survivors often suffer different kinds of disabilities in terms of their cognitive and motor capabilities, and are therefore unable to perform their day-to-day activities. To regain some of their cognitive as well as motor abilities, they require rehabilitation. To this end, we present a serious game framework based on augmented reality technology that may motivate the patients’ involvement in the rehabilitation exercise. Additionally, we analyze the requirements for such a framework and describe the concept and implementation of the proposed approach. Furthermore, we designed a wireless vibrotactile output device that is attached to a tangible object. The tangible object that is connected to the framework can give haptic as well as audio-visual feedback to the patient in a more motivating and entertaining environment for rehabilitation exercises. The suitability and utility of the proposed framework was evaluated with real stroke patients and compared against the performance of a healthy control group, thus facilitating occupational therapists in assessing a patient’s progress. Our evaluations show that the serious games with vibrotactile feedback are well accepted by patients. 相似文献
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Werner Heimann und Verena Klaiber 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1977,165(3):131-136
Zusammenfassung Die Untersuchung einer aus Roggen gewonnenen Lipoxygenase-aktiven Enzymfraktion ergab, daß Roggenlipoxygenase ein Molekulargewicht von ca. 102000 besitzt. Bei der isoelektrischen Fokussierung traten zwei Bandengruppen mit isoelektrischen Punkten zwischen 5,1–5,5 und 5,8–6,4 auf. Durch Ionenaustauschchromatographie konnten drei Isoenzyme gewonnen werden. Das pH-Optimum der Umsetzung lag bei 7,3–7,5. Roggenlipoxygenase katalysiert vorwiegend die Bildung von 13-Hydroperoxy-9-cis,11-trans-octadecadiensäure (13-LHPO). Durch eine hochmolekulare Proteinfraktion wurden in Roggen die LHPO zu a-Ketolen umgesetzt. Diese Roggenisomerase setzt die von der systemeigenen Lipoxygenase gebildeten LHPO zu überwiegend 12,13-Ketohydroxysduren um. Roggenisomerase hat eine Michaeliskonstante von 3–5 × 10–5, (LHPO). Die Reaktionsgeschwindigkeit der Umsetzung stieg bei kleinen Proteinkonzentrationen linear mit der Proteinkonzentration.
On lipoxygenase and enzymes which decompose linoleic acid hydroperoxides in rye
Summary An enzyme fraction from rye containing lipoxygenase activity was investigated. The molecular weight of lipoxygenase was found to be about 102000. Two bands groups with isoelectric points between 5.1–5.5 and 5.8–6.4 were obtained by isoelectric focusing. Three isoenzymes could be separated by ion exchange chromatography. Lipoxygenase has optimum activity at pH 7.3–7.5 and predominantly forms 13-hydroperoxy-9-cis,11-trans-octadecadienoic acid (13-LHPO).In rye the 13-LHPO is converted to -ketols by a high molecular protein fraction. This isomerase converts the LHPO formed by rye lipoxygenase predominantly to 12,13-ketohydroxy acids. The Michaelis Constant of isomerase is 3–5 × 10–5, using LHPO as substrate. At low protein concentrations the reaction velocity of LHPO-conversion increases linearly with protein concentration.相似文献
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The resistance of 330 coagulase-negative staphylococci (CNS) associated with food or used in starter cultures and belonging to the species Staphylococcus carnosus, Staphylococcus condimenti, Staphylococcus piscifermentans, Staphylococcus equorum, Staphylococcus succinus and Staphylococcus xylosus, against 21 antibiotics was determined using the disk diffusion method. The incidence and number of resistances was found to be species and source of isolation dependent. Most strains of S. equorum (63%), S. succinus (90%) and S. xylosus (95%) exhibited resistances against up to seven antibiotics, whereas only few strains of S. carnosus (12%) and S. piscifermentans (27%) were antibiotic resistant. Resistances to lincomycin, penicillin, fusidic acid, oxacillin, ampicillin and tetracycline were predominant. Among strains of S. xylosus, the incidence of resistance ranged from 22% for tetracycline up to 69% for penicillin. Concerning the source of isolation, resistances were often determined in strains of S. equorum, S. succinus and S. xylosus isolated from cheese (87%) and sausage (83%), and strains of S. xylosus obtained from meat starter cultures (93%). Remarkably, all CNS were sensitive to the clinically important antibiotics chloramphenicol, clindamycin, cotrimoxazol, gentamicin, kanamycin, linezolid, neomycin, streptomycin, synercid and vancomycin. The phenotypic resistances to ss-lactam antibiotics, lincomycin and tetracycline were verified by PCR amplification and could be traced back to the genes blaZ, lnuA and tetK, respectively. This study permitted a comprehensive insight into the incidence of antibiotic resistances in food-associated CNS. 相似文献
6.
Pelle Willumsen Josef Oehmen Verena Stingl Joana Geraldi 《International Journal of Project Management》2019,37(5):731-749
Risk management is a common and widely adopted project practice. Practitioners use risk management based on a common assumption that risk management adds value to projects. Yet, in the complex and ambiguous environment of a project, value is often subjective. If this is the case, then how do stakeholders perceive project risk management to create value? This paper presents a literature review and an empirical study of project risk management as a means of creating value. The empirical study is based on interviews, analyzed through qualitative analysis, to unravel the subjective value of project risk management. Specifically, we addressed how practitioners perceived the connection between project risk management practices and value creation. We found that stakeholders' perceptions of value played an important role in how value was created through project risk management. What a stakeholder perceives to be important, such as the prospective outcomes of a project, influences the perceived value of a given project risk management practice. The empirical findings indicate the need for a contextualized understanding of the value of project risk management, and thereby provide a more nuanced view of the variety of forms through which project risk management can create value. The findings question the “universal ideal” of PRM value creation portrayed in the academic and practitioner literature. 相似文献
7.
Despite the huge technical and market potential for cost-effective energy efficiency investments in Southeast Asian markets, only a small fraction of this potential has been realised. Given that the major share of global future energy demand, and associated greenhouse gas emissions, will come from emerging economies, it is important to understand the barriers to mainstreaming energy efficiency into the financial sector. This paper focuses on public initiatives that support one of the main barriers: access to capital. The researchers chose Thailand as a case study because of the range of energy efficiency finance programmes that have been designed and implemented since the early 1990s. Interviews with 21 experts from government, the private sector and academia provided the core data for this research. The analysis employed a multi-level perspective and focused on the historical evolution of public support of energy efficiency finance in the country. We identified three distinct phases of public policy development over the past two decades. Despite an impressive variety of ambitious and creative programmes, the initiatives have not yet succeeded in integrating energy efficiency into the financial sector in a meaningful way. Some of the key lessons found are that (a) it is better to treat energy efficiency and renewable energy in separate financing initiatives, (b) governments find it challenging to design effective mechanisms to de-risk financial investments, and (c) international organisations play an important role in testing and facilitating the introduction of new financing approaches and mechanisms. In emerging economies, cost-effective implementation of energy efficiency measures is a promising alternative that can reduce the need for investment in large-scale power generation capacity. The researchers hope that this paper will contribute to more effective design of programmes to incentivise energy efficiency financing in Thailand and in other economies in Southeast Asia. 相似文献
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