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91.
Collybia nivalis, Favolaschia sp. 87129, Pterula sp. 82168 and Omphalotus olearius were cultivated on natural substrates. The antibiotic metabolites oudemansin A. strobilurins A, D, illudin S and pterulone were isolated and identified. A new antifungal metabolite, pterulone B, was described from cultures of Pterula sp. 82168 on wood. Collybia nivalis was found to be the first species of this genus to produce strobilurins and oudemansin A. As compared to rich media the cultivation on natural substrates resulted in the production of fewer metabolites. The concentrations of the antibiotics, however, were sufficient to inhibit other saprophytic fungi. 相似文献
92.
A Gericke ER Smith DJ Moore R Mendelsohn J Storch 《Canadian Metallurgical Quarterly》1997,36(27):8311-8317
Fatty acid-binding proteins (FABPs) found in many tissues constitute a family of low molecular weight proteins that are suggested to function as intracellular transporters of fatty acids. Studies of the transfer kinetics of fluorescent anthroyloxy-labeled long-chain fatty acids from FABP to model membranes led to the suggestion that the FABPs, typically considered to be cytosolic proteins, could nevertheless interact directly with membranes [Wootan, M. G., et al. (1993) Biochemistry 32, 8622-8627]. In the current study, the interaction of the adipocyte FABP (A-FABP) with vesicles of various phospholipids has been directly measured and confirmed with FTIR spectroscopy. The strength of this interaction was inferred from the lowering of the gel-liquid-crystal phase transition temperature as monitored from temperature-induced variations in the acyl chain CH2 stretching frequencies and from the intensities of the components of the CH2 wagging progressions. A-FABP interacts more strongly with anionic phospholipids (phosphatidylserine and cardiolipin) than with zwitterionic phosphatidylcholine. Unsaturation in the acyl chains leads to a greater reduction in Tm (stronger lipid-protein interaction). In contrast, neutralization of A-FABP surface charges by acetylation considerably weakens the interaction. Comparison of the shifts in lipid melting temperatures with those induced by other proteins suggests that A-FABP behaves like a typical peripheral membrane protein. The degree of membrane interaction correlates directly with the rate of fatty acid transfer, suggesting that contact between A-FABP and membranes is functionally related to its fatty acid transport properties. As expected, the protein exhibits a predominantly beta-sheet structure. It was found to aggregate with increasing temperature. With the exception of minor differences between the pure and lipid-associated A-FABP in the 1640-1660 cm-1 region, both the protein structure and thermal stability appeared essentially unchanged upon interaction with the lipid. 相似文献
93.
F Wu A Gericke CR Flach TR Mealy BA Seaton R Mendelsohn 《Canadian Metallurgical Quarterly》1998,74(6):3273-3281
Annexins comprise a family of proteins that exhibit a Ca2+-dependent binding to phospholipid membranes that is possibly relevant to their in vivo function. Although substantial structural information about the ternary (protein/lipid/Ca2+) interaction in bulk phases has been derived from a variety of techniques, little is known about the temporal and spatial organization of ternary monolayer films. The effect of Ca2+ on the interactions between annexin V (AxV) and anionic DMPA monolayers was therefore investigated using three complementary approaches: surface pressure measurements, infrared reflection-absorption spectroscopy (IRRAS), and Brewster angle microscopy (BAM). In the absence of Ca2+, the injection of AxV into an aqueous subphase beneath a DMPA monolayer initially in a liquid expanded phase produced BAM images revealing domains of protein presumably surrounded by liquid-expanded lipid. The protein-rich areas expanded with time, resulting in reduction of the area available to the DMPA and, eventually, in the formation of condensed lipid domains in spatial regions separate from the protein film. There was thus no evidence for a specific binary AxV/lipid interaction. In contrast, injection of AxV/Ca2+ at a total Ca2+ concentration of 10 microM beneath a DMPA monolayer revealed no pure protein domains, but rather the slow formation of pinhead structures. This was followed by slow (>2 h) rigidification of the whole film accompanied by an increase in surface pressure, and connection of solid domains to form a structure resembling strings of pearls. These changes were characteristic of this specific ternary interaction. Acyl chain conformational order of the DMPA, as measured by nu(sym)CH2 near 2850 cm(-1), was increased in both the AxV/DMPA and AxV/DMPA/Ca2+ monolayers compared to either DMPA monolayers alone or in the presence of Ca2+. The utility of the combined structural and temporal information derived from these three complementary techniques for the study of monolayers in situ at the air/water interface is evident from this work. 相似文献
94.
Hofmann Stefan G.; Newman Michelle G.; Ehlers Anke; Roth Walton T. 《Canadian Metallurgical Quarterly》1995,104(1):224
Individuals meeting criteria of the revised third edition of Diagnostic and Statistical Manual for Mental Disorders (American Psychiatric Association, 1987) for social phobia with a fear of speaking in front of people were subdivided into those with (n?=?16) and without (n?=?14) avoidant personality disorder (APD). These individuals and nonanxious controls (n?=?22) spoke in front of a small audience while speaking time, subjective anxiety, fearful thoughts, and electrocardiographic and respiratory measures were recorded. Controls spoke for longer than either social phobia group. Those with social phobia and APD reported more subjective anxiety and more fear cognitions than the other two groups; phobic individuals without APD showed greater heart rates in the phobic situation than either social phobics with APD or controls. The latter two groups did not differ in heart rate. These results indicate incongruent subjective and heart rate responses to the feared situation. A similar pattern of results was found when participants were divided into generalized and specific social phobia groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Intrusive reexperiencing in posttraumatic stress disorder (PTSD) has been linked to perceptual priming for trauma-related material. A prospective longitudinal study (N = 69) investigated perceptual priming for trauma-related, general threat, and neutral words in assault survivors with and without PTSD, using a new version of the word-stem completion task. Survivors with PTSD showed enhanced priming for trauma-related words. Furthermore, priming for trauma-related words measured soon after the trauma was associated with subsequent PTSD severity at 3, 6, and 9 months. The enhanced priming effect was specific to trauma-related words. Enhanced perceptual priming for traumatic material appears to be one of the cognitive processes operating in PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Hans-Georg Fill Anke Gericke Dimitris Karagiannis Robert Winter 《WIRTSCHAFTSINFORMATIK》2007,49(6):419-429
The development of models and methods is a vital element of design science in information systems research. In this paper a formal process modeling language is developed which incorporates IEB (Integrated Enterprise Balancing)/4R (Risk, Return, Regulation, Reporting) requirements formulated by Faisst and Buhl [FaBu05]. This is realized through the inclusion of 4R elements and 4R relations into the new 4R process modeling language. An evaluation of the process modeling language with regard to the assessment criterion “feasibility of implementation” was successfully executed using the meta modeling platform ADONIS. For that purpose the ADONIS modeling language for business processes (ADONIS BPMS) was extended with additional 4R modeling elements. Furthermore a new model type as well as required classes and relation classes have been developed which enable the connection of the 4R process modeling language to the research results of the above mentioned contribution. 相似文献
97.
98.
Fengjing Jiang Anke Kaltbeitzel Junliang Zhang Wolfgang H. Meyer 《International Journal of Hydrogen Energy》2014
Poly(4-vinyl pyridine) nano-spheres (P4VP-NS) stabilized poly(vinyl phosphonic acid) (PVPA) membranes were prepared as proton conducting membranes for fuel cells. The acid–base interactions between P4VP-NS and PVPA were utilized to improve the dimensional and thermal stability of PVPA. In this work, the effects of acid–base interactions on proton conductivity and thermal stability were quantitatively determined and discussed based on the results of 1H magic-angle-spin NMR (1H MAS NMR), Fourier transfer infrared spectroscopy (FTIR) and impedance spectroscopy measurements. 相似文献
99.
Business intelligence and information logistics have become a part of teaching curricula in recent years due to their importance for companies and the request for adequately trained graduates. Since these fields are characterized by a high amount of software and methodology innovations, teaching materials and teaching aids require constant attention. Teradata, a division of NCR Corp., has teamed up with lecturers and researchers to build and run a portal to support teaching business intelligence and information logistics. This article describes how faculty can use the Teradata University Network to prepare and run courses by reusing teaching materials and running state-of-the-art, commercial software provided in an ASP model. 相似文献
100.
Udder defence mechanisms are not completely explained by current mastitis research. The anatomical construction of the udder implies that infection of one udder quarter does not influence the immune status of neighbouring quarters. To test this hypothesis, we compared the immune reactions of individual udder quarters in response to microbial attacks. In the course of immune reactions, polymorphonuclear leucocytes (PMN) release oxygen radicals, which can be determined by chemiluminescence (CL). Milk from 140 udder quarters of 36 cows was analysed for somatic cell count (SCC), differential cell count, viability and CL activity. Quarters with an SCC < 100,000 cells/ml and free of pathogens were defined as uninfected, all other quarters were categorized as infected. Three groups of cows were classified cytologically: group A (healthy, 11 animals, SCC limit < 100,000 cells/ml); group B (moderate mastitis, 8 cows, SCC > or = 100,000 and < 400,000 cells/ml in at least one quarter); and group C (severe mastitis, 17 cows, SCC > or = 400,000 cells/ml in at least one quarter). Infected and uninfected quarters in groups B and C were analysed separately. Viability of PMN leucocytes was significantly (P=0.0012) lower in group A (72.6%) than in healthy quarters of group C (84.0%). Lowering the SCC limit of healthy quarters to <50,000 cells/ml (group A: all quarters within the udder) revealed striking differences between samples of groups B and C: in addition to varying differential cell counts and viabilities, CL activity of group B<50 (2929 CL units/million PMN) was markedly lower than that of the other groups (5616 in group A<50 and 6445 CL units/million PMN in group C<50). These results allow the conclusion that the infection of one udder quarter influences the cell activity of neighbouring quarters. When the SCC threshold for healthy quarters was reduced to 50,000 cells/ml, greater differences in cell activities were detected between healthy udders and healthy quarters of infected udders. 相似文献