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211.
Dubsky P Hayden H Sachet M Bachleitner-Hofmann T Hassler M Pfragner R Gnant M Stift A Friedl J 《Cancer immunology, immunotherapy : CII》2008,57(6):859-870
BACKGROUND: Recent preclinical and clinical evidence suggests the use of allogeneic tumor as a source of antigen for DC-based immunotherapy against cancer. We hypothesized that addition of allogeneic tumor lysate to monocyte-derived DC culture could serve a dual purpose: (1) antigen source and (2) protein supplementation of DC culture media. Protein supplementation whether of known origin (human serum/plasma, fetal bovine serum, human serum albumin) or undeclared origin ("serum-free" media) is a source of variability and bias. We addressed the question whether protein supplementation can be omitted in the presence of allogeneic tumor lysate. MATERIALS AND METHODS: Human DC cultured in the presence of lysate from medullary thyroid carcinoma (MTC) cell line SHER-I (TuLy-DC) and DC pulsed with the same lysate but cultured in the presence of FBS (FBS-DC) were assessed for morphology, phenotype, maturation and functional properties. RESULTS: In comparison of FBS-DC/TuLy-DC no significant differences in morphology, phenotype and maturation could be detected. Both culture conditions produced CD1a(high), CD14(low) DC with high expression of costimulatory molecules and CD83 upon stimulation. TuLy-DC gave significantly better yields and produced more IL12p70. DC showed high (allo)stimulatory capacity toward T-cells. TuLy-DC induced more intracellular IFNgamma in CD8+T-cells of vaccinated MTC patients. Both types of DC induced killing of SHER-I after short in vitro restimulation. Tumor lysate from SHER-I can substitute for further protein supplementation in DC culture. Allogeneic tumor lysates should be taken into consideration as both source of antigen and protein supplementation in monocyte-derived DC culture. 相似文献
212.
Interspecific hybridization is considered a possible mechanism of plant diversification. The Andes are a hotspot of biodiversity, but hybridization in Andean taxa has so far not been investigated intensively. The current study investigates crossability in Caiophora (Loasaceae subfam. Loasoideae) by experimental interspecific hybridization of seven different species. Hand pollination was undertaken, developing fruits counted, thousand (seed) grain weights, and seed viability were examined. Cross pollination led to some fruit set in 36 of the 37 different combinations. Overall fruit set was virtually identical irrespective of the combination of parental plants. Mean germination rates were much higher in hybrid seeds, indicating a marked heterosis effect and the possible presence of an inbreeding depression in the source populations: In experimental hybridization the divergent taxa of Caiophora behave like isolated, inbred populations of a single species. Allopatry and different habitat preferences seem to be the key factors keeping the (interfertile) taxa of Caiophora apart in the apparent absence of both postmating isolating mechanisms and obvious isolating mechanisms in phenology and floral biology. Interspecific hybrids reported from the wild appear to be the result of secondary contact due to human impact. 相似文献
213.
Michaela Kupka 《BBA》2008,1777(1):94-103
Optical spectroscopic properties of the covalently linked chromophores of biliproteins are profoundly influenced by the state of the protein. This has been used to monitor the urea-induced denaturation of C-phycocyanin (CPC) from Mastigocladus laminosus and its subunits. Under equilibrium conditions, absorption, fluorescence and circular dichroism of the chromophores were monitored, as well as the circular dichroism of the polypeptide. Treatment of CPC trimers (αβ)3 resulted first in monomerization (αβ), which was followed by a complex unfolding process of the protein. Loss of chromophore fluorescence is the next process at increasing urea concentrations; it indicates increased flexibility of the chromophore while maintaining the native, extended conformation, and a less compact but still native-like packing of the protein in the regions sampled by the chromophores. This was followed by relaxation of the chromophores from the energetically unfavorable extended to a cyclic-helical conformation, as reported by absorption and CD in the visible range, indicating local loss of protein structure. Only then is the protein secondary structure lost, as reported by the far-UV CD. Sequential processes were also seen in the subunits, where again the chromophore-protein interactions were reduced before the unfolding of the protein. It is concluded that the bilin chromophores are intrinsic probes suitable to differentiate among different processes involved in protein denaturation. 相似文献
214.
Michaela Kiernan Abby C. King Marcia L. Stefanick Joel D. Killen 《Obesity (Silver Spring, Md.)》2001,9(12):770-777
Objective: Adding exercise to a comprehensive weight‐loss program might not only attenuate any psychological distress associated with weight‐loss attempts but also may provide psychological benefits. This study examined whether a diet‐plus‐exercise weight‐loss program improved psychological outcomes more than a diet‐only weight‐loss program or an assessment‐only control group. Research Methods and Procedures: This study was part of a larger 1‐year randomized weight‐loss trial examining the effects of diet and exercise on cardiovascular disease risk factors in 264 overweight adults. Psychological measures specific to weight control (e.g., cognitive restraint, disinhibition, hunger, and body dissatisfaction) as well as traditional measures of psychological distress (e.g., symptoms of depression, anxiety, and stress) were obtained at baseline and 1 year. Results: Men and women in either weight‐loss program reported greater restraint, less disinhibition, and less hunger at 1 year than those in no program. Men in the diet‐plus‐exercise program experienced additional increases in restraint and decreases in hunger than did men in the diet‐only program. Women in the diet‐plus‐exercise program did not experience additional psychological benefits specific to weight control than those in the diet‐only program, despite increases in aerobic capacity. Discussion: The pattern seen for overweight men in the diet‐plus‐exercise program at 1 year—greater restraint, less disinhibition, and less hunger—is similar to the pattern seen in successful weight maintainers. These results underscore the need for innovative strategies that will enhance and sustain the pattern of psychological benefits specific to weight control associated with successful weight loss, especially for overweight women. 相似文献
215.
Thomas N. Robinson Michaela Kiernan Donna M. Matheson K. Farish Haydel 《Obesity (Silver Spring, Md.)》2001,9(5):306-312
Objective: Identifying parental behaviors that influence childhood obesity is critical for the development of effective prevention and treatment programs. Findings from a prior laboratory study suggest that parents who impose control over their children's eating may interfere with their children's ability to regulate intake, potentially resulting in overweight. These findings have been widely endorsed; however, the direct relationship between parental control of children's intake and their children's degree of overweight has not been shown in a generalized sample. Research Methods and Procedures: This study surveyed 792 third‐grade children with diverse ethnic and socioeconomic backgrounds from 13 public elementary schools. Parental control over children's intake was assessed through telephone interviews using a state‐of‐the‐art instrument, and children were measured for height, weight, and triceps skinfold thickness. Results: Counter to the hypothesis, parental control over children's intake was inversely associated with overweight in girls, as measured by body mass index, r = ?0.12, p < 0.05, and triceps skinfolds, r = ?0.11, p < 0.05. This weak relationship became only marginally significant when controlling for parents’ perceptions of their own weight, level of household education, and children's age. No relationship between parental control of children's intake and their children's degree of overweight was found in boys. Discussion: Previous observations of the influence of parental control over children's intake in middle‐class white families did not generalize to 8‐ to 9‐year‐olds in families with diverse socioeconomic and ethnic backgrounds. The present findings reveal a more complex relationship between parental behaviors and children's weight status. 相似文献
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217.
Michaela Schratzberger Stefan Bolam Karema Warr 《Journal of experimental marine biology and ecology》2006,334(2):244-255
The use of fine-grained maintenance dredged material for habitat enhancement has increased in recent years, particularly recharge schemes which provide a means of combating the erosion of intertidal flats and saltmarsh. This article investigates the development of meiofaunal nematode communities following a natural experiment in 2003, when fine-grained dredged material was deposited concurrently at four adjacent intertidal recharge sites on the southeast coast of the United Kingdom. A 12-month survey of nematode assemblages was carried out to compare univariate, multivariate, allometric and functional attributes of colonist communities in relation to the different environmental conditions prevailing at the four sites. Developing assemblages were increasingly affected by the spatial differences in the elevation, consolidation and exposure of bed material. The results indicated that the colonisation sequence was the result of random settling of suspended nematodes, sequential reproduction and differential survival and reproductive success of colonising species. For the first time, this experiment provided insights into the development of adaptive and functional types of meiofaunal nematodes following the intertidal deposition of uncontaminated fine-grained dredged material. This, in turn, will contribute considerably to the development of ecological models of the evolution of the large-scale placement of muddy dredged material in the intertidal environment. 相似文献
218.
Background The cost–benefit model for the evolution of botanical carnivory provides a conceptual framework for interpreting a wide range of comparative and experimental studies on carnivorous plants. This model assumes that the modified leaves called traps represent a significant cost for the plant, and this cost is outweighed by the benefits from increased nutrient uptake from prey, in terms of enhancing the rate of photosynthesis per unit leaf mass or area (AN) in the microsites inhabited by carnivorous plants.Scope This review summarizes results from the classical interpretation of the cost–benefit model for evolution of botanical carnivory and highlights the costs and benefits of active trapping mechanisms, including water pumping, electrical signalling and accumulation of jasmonates. Novel alternative sequestration strategies (utilization of leaf litter and faeces) in carnivorous plants are also discussed in the context of the cost–benefit model.Conclusions Traps of carnivorous plants have lower AN than leaves, and the leaves have higher AN after feeding. Prey digestion, water pumping and electrical signalling represent a significant carbon cost (as an increased rate of respiration, RD) for carnivorous plants. On the other hand, jasmonate accumulation during the digestive period and reprogramming of gene expression from growth and photosynthesis to prey digestion optimizes enzyme production in comparison with constitutive secretion. This inducibility may have evolved as a cost-saving strategy beneficial for carnivorous plants. The similarities between plant defence mechanisms and botanical carnivory are highlighted. 相似文献
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220.