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131.
Caulobacter crescentus and Aquabacterium commune, both isolated from drinking water, as well as environmental isolates of Pseudomonas aeruginosa and Enterococcus faecium were treated with different UV fluences to study their capacity to restore induced DNA damages. Here, the induction of a key mechanism of bacterial dark repair, the so-called recA system, was analysed. With newly designed probes, the specific recA mRNA was detected by Northern blot. Additionally, the RecA protein was measured by the Western blot technique using a specific antibody. In drinking water bacteria as well as in opportunistic microorganisms, a specific induction of dark repair mechanisms was found even at UV fluences higher than 400J/m(2), the German standard for UV disinfection. This induction depended on the incubation time after UV treatment. Nevertheless, the UV-induced recA expressions were found to differ in the bacteria under investigation. 相似文献
132.
Jesper Lundbom Marjukka Kolehmainen Leena Pulkkinen Pasi Soininen Mika Tiainen Ursula Schwab Matti Uusitupa Markku Tammi 《European Journal of Lipid Science and Technology》2010,112(12):1308-1314
The aim of this study was to evaluate use of infrared spectroscopy for measuring adipose tissue triacylglycerols (TAGs) with analysis by multivariate curve resolution (MCR). The mid‐infrared spectrum was measured with an attenuated total reflection accessory from a lipid droplet pressed from adipose tissue. The obtained spectra were characteristic of pure TAG spectra and water and protein contamination could be easily identified from specific spectral regions. MCR analysis of the olefinic (?C? H) stretch (3006 cm?1), resolved the different contributions of monounsaturated (MUFA) and polyunsaturated (PUFA) double bonds. Similar MCR analysis of the trans (HC?CH? ) region (966 cm?1), resolved the differing contributions of isolated trans isomers (transFA) and CLA. The PUFA double bond content of 16 subjects was negatively correlated with concentrations of serum total cholesterol R = ?0.498 (p = 0.050) and triacylglycerols R = ?0.609, (p = 0.016). The transFA content exhibited a negative, although non‐significant, correlation to high‐density lipoprotein (HDL)‐cholesterol (R = ?0.483, p = 0.068). The present study shows that MCR analysis of adipose tissue TAG infrared spectra can be used to estimate differences in the fatty acid (FA) profiles in population studies. Infrared spectroscopy in combination with MCR provides a robust method for assessing a FA profile of human adipose tissue. Practical applications: This study has highlighted the use of MCR to enhance the information obtained from infrared spectra. This new approach provides a robust method for assessing a FA profile of human adipose tissue lipids. 相似文献
133.
Clinical applications of glass-ceramics in dentistry 总被引:3,自引:0,他引:3
Höland W Rheinberger V Apel E van 't Hoen C Höland M Dommann A Obrecht M Mauth C Graf-Hausner U 《Journal of materials science. Materials in medicine》2006,17(11):1037-1042
Glass-ceramics featuring special properties can be used as a basis to develop biomaterials. It is generally differentiated
between highly durable biomaterials for restorative dental applications and bioactive glass-ceramics for medical use, for
example, bone replacements. In detail, this paper presents one biomaterial from each of these two groups of materials.
In respect to the restorative dental biomaterials, the authors give an overview of the most important glass-ceramics for clinical
applications. Leucite, leucite-apatite, lithium disilicate and apatite containing glass-ceramics represent biomaterials for
these applications. In detail, the authors report on nucleation and crystallization mechanisms and properties of leucite-apatite
glass-ceramics. The mechanism of apatite nucleation is characterized by a heterogeneous process. Primary crystal phases of
α - and β -NaCaPO4 were determined.
Rhenanite glass-ceramics represent biomaterials with high surface reactivity in simulated body fluid, SBF, and exhibit reactive
behaviour in tests with bone cells. Cell adhesion phenomena and cell growth were observed. Suitable colonization and proliferation
and differentiation of cells as a preliminary stage in the development of a material for bone regeneration applications was
established. The authors conclude that the processes of heterogeneous nucleation and crystallization are important for controlling
the required reactions in both biomaterial groups. 相似文献
134.
Dervillez X Hüther A Schuhmacher J Griesinger C Cohen JH von Laer D Dietrich U 《ChemMedChem》2006,1(3):330-339
A major drawback of therapeutic peptides is their short half-life, which results in the need for multiple applications and high synthesis costs. To overcome this, we established a eukaryotic expression system that allows the stable expression of small therapeutic peptides by multimerisation. By inserting the sequence encoding the therapeutic peptide between a signal peptide and the multimerising domain of the alpha-chain from the human C4bp plasma protein, therapeutic peptides as small as 5 kDa are secreted as multimers from transfected cells; this allows easy purification. As proof of principle, we show that the T20-derived HIV-1 fusion inhibitory peptide C46 in its multimeric form: i) was efficiently secreted, ii) was more stable than the current antiviral drug T20 in vitro and in vivo, and iii) inihibited HIV-1 entry with similar efficiency in vitro. Besides the gain in stability, multimerisation also leads to increased valency and allows the combination of several therapeutic functions. Furthermore, by expressing the multimers from cells, post-translational modifications could easily be introduced. 相似文献
135.
Staudinger Ursula M.; Fleeson William; Baltes Paul B. 《Canadian Metallurgical Quarterly》1999,76(2):305
Predictors of subjective physical health and global well-being were compared in a representative U.S. (N?=?2,400) and a German (N?=?1,607) sample of adults (age range: 25–65 years). Because of cultural overlap between Western industrialized nations, similarities in predictive patterns were expected. Differences in the economic and social systems as well as the cultural background, however, should also generate differences. As expected, the overall predictive power of the three sets of predictors (sociostructural variables, personality traits, and self-regulatory characteristics) was sizable in both countries. The strongest unique predictors were self-regulatory indicators for subjective physical health and personality traits for global well-being. In addition, however, theory-consistent country differences emerged in how personal and social resources seem to be orchestrated to maximize well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
136.
Christoph Kessel Dr. Wolfhart Kreuz Dr. Katharina Klich Karin Becker‐Peters Frank Vorpahl Ursula Dietrich Dr. Thomas Klingebiel Dr. Christoph Königs Dr. 《ChemMedChem》2009,4(8):1364-1370
About 30 % of patients with severe hemophilia A develop neutralizing antibodies (inhibitors) to coagulation factor VIII (FVIII) upon treatment with exogenous factor preparations. Two peptides, C6 (NPVENMMDRDSQ) and H10 (QSPWQTWFTRAL), that mimic putative inhibitor epitopes (mimotopes), were previously selected by phage display screening of plasma samples from patients with inhibitors. Synthetic peptide mimotopes inhibited IgG binding to FVIII (IC50: 30–50 μM ). This effect was increased by an equimolar combination of both mimotopes. Mimotopes were fused to the C‐terminal multimerization domain of the C4bp α‐chain and expressed as multimers in 293T cells. Multimerized mimotopes showed improved binding to anti‐FVIII IgG and prolonged in vitro half‐life relative to synthetic peptides. The two mimotopes were combined in heteromultimers by co‐transfection of 293T cells with respective vectors, resulting in bi‐specific molecules that almost completely blocked polyclonal antibody binding to FVIII (IC50: 2–3 μM ). This strategy is capable of functionally improving synthetic peptides by multimerization and could provide a basis for novel therapeutic approaches for patients with hemophilia A and inhibitors. 相似文献
137.
Pasupathi Monisha; Staudinger Ursula M.; Baltes Paul B. 《Canadian Metallurgical Quarterly》2001,37(3):351
The present study examined adolescents' wisdom-related knowledge and judgment with a heterogeneous sample of 146 adolescents (ages 14–20 years) and a comparison sample of 58 young adults (ages 21–37 years). Participants responded to difficult and ill-defined life dilemmas; expert raters evaluated these responses along 5 wisdom criteria. Our findings confirmed that in contrast to adulthood, adolescence is a major period for normative age-graded development in knowledge about difficult life problems. Adolescents performed at lower levels than young adults but also demonstrated substantial age increments in performance. As expected, adolescents' performance varied as a function of criterion and gender. These results hold implications for research on adolescent development and for the development of wisdom-related knowledge and judgment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
138.
The aim of the present study was to investigate age-related differences in self-reported affect in adulthood. Measurement of affect encompassed high- and low-arousal positive and negative affect. The sample consisted of 277 participants who were between 20 and 80 years old. Older participants showed a higher level of low-arousal positive affect and did not significantly differ from the two younger age groups in high-arousal positive affect. Both high- and low-arousal negative affect decreased from middle to older adulthood. Only partially are these age effects explained by sociodemographic characteristics, education, or self-reported health and personality. The perceived regulation of affect in the face of difficulties or threatening situations emerged as a central mediator in the association between age and the three age-graded facets of affect. In contrast, future time perspective had no mediating effect on the age–affect relationship. Results suggest that age-related advantages in perceived affect regulation seem to be one central component of resilience in old age. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
139.
Ursula Eschenhagen Martin Eschenhagen Frank Ludwig Angelika Kiessling Kristin Symank Elke Boschke Isolde Röske Thomas Bley 《European Food Research and Technology》2008,227(4):995-999
In this study, catalyzed reporter deposition in situ hybridization (CARD—ISH) with tetramethylbenzidine (TMB) was used for
rapid detection of the food pathogens Salmonella typhimurium and Escherichia coli. The bacteria in a sample were concentrated by membrane filtration. The filter membranes with the cells thus removed were
incubated on nutrient agar for 4–5 h to allow the formation of microcolonies. Instead of fluorescent tyramide, 3,3′,5,5′-tetramethylbenzidine
(TMB), which yields a blue precipitate, was used for signal amplification after in situ hybridization. Microcolonies amplified
with TMB produced blue signals, which were sufficiently intense to allow visual evaluation either using a stereomicroscope,
or even with the naked eye. Therefore even low cell numbers of hygienically critical bacteria can be detected on the filter
membrane without a protracted examination. This enables the detection of low cell numbers (<10 cfu) in a sample of 100 ml
tap water within 9–10 h. 相似文献
140.
Ursula Klein 《NTM》2008,16(2):277-278
Ohne Zusammenfassung
The online version of the original article can be found under doi:. 相似文献