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51.
Characterization of the state of differentiation of six newly established human non-small-cell lung cancer cell lines 总被引:6,自引:0,他引:6
Gerold Bepler Angelika Koehler Paul Kiefer Klaus Havemann Karin Beisenherz Gabriele Jaques Claus Gropp Maria Haeder 《Differentiation; research in biological diversity》1988,37(2):158-171
Six new non-small-cell lung cancer (NSCLC) cell lines were established directly from human tissue or indirectly via nude mouse xenografts in serum-supplemented media with success rates of 8% and 13%, respectively. They comprised one adenocarcinoma (ADLC-5M2), two squamous cell carcinomas (EPLC-32M1, EPLC-65H), two large cell carcinomas (LCLC-97TM1, LCLC-103H), and one malignant biphasic mesothelioma (MSTO-211H). All cell lines grew adherent to culture vessels with population doubling times (PDT) of 16-40 h, formed colonies in soft agarose with efficiencies of 0.1%-5.1%, and all grew in athymic nude mice. Xenograft histologies appeared as follows: (a) undifferentiated carcinomas with feeble resemblance to the original tumors in the case of adenocarcinomas and squamous cell carcinomas; (b) large cell carcinoma with high resemblance to the original tumor; (c) an undifferentiated tumor with predominance of large epithelial cells and few fibrous cells in the case of mesothelioma. Human chorionic gonadotropin (HCG) was found by radioimmunoassay and high-affinity binding sites for epidermal growth factor (EGF) by radio-receptor assay in 4/4 cell lines. A very low activity of L-DOPA decarboxylase (DDC) was detectable only in the adenocarcinoma cell line. All cell lines overexpressed the c-myc protooncogene, and no gene rearrangement or amplification was observed. Chromosome analysis revealed modal chromosome numbers of 70-73 in ADLC-5M2, EPLC-32M1, EPLC-65H, and MSTO-211H. Cell lines derived from large cell carcinoma had modal values of 65 and 170 and a wider chromosome distribution than all other cell lines. A NSCLC specific chromosomal aberration has been undetectable until now. These cell lines may aid in elucidating the biology of NSCLC and its interrelationship to other lung tumors. 相似文献
52.
Hans J. De Boeck Juliette M. G. Bloor Rien Aerts Michael Bahn Claus Beier Bridget A. Emmett Marc Estiarte Jos M. Grünzweig Aud H. Halbritter Petr Holub Anke Jentsch Karel Klem Juergen Kreyling Gyrgy Krel‐Dulay Klaus Steenberg Larsen Alexandru Milcu Jacques Roy Bjarni D. Sigurdsson Melinda D. Smith Marcelo Sternberg Vigdis Vandvik Thomas Wohlgemuth Ivan Nijs Alan K. Knapp 《Global Change Biology》2020,26(2):e6-e7
53.
Nicolas Rapin Can Kesmir Sune Frankild Morten Nielsen Claus Lundegaard Søren Brunak Ole Lund 《Journal of biological physics》2006,32(3-4):335-353
Over the past decade a number of bioinformatics tools have been developed that use genomic sequences as input to predict to
which parts of a microbe the immune system will react, the so-called epitopes. Many predicted epitopes have later been verified
experimentally, demonstrating the usefulness of such predictions. At the same time, simulation models have been developed
that describe the dynamics of different immune cell populations and their interactions with microbes. These models have been
used to explain experimental findings where timing is of importance, such as the time between administration of a vaccine
and infection with the microbe that the vaccine is intended to protect against. In this paper, we outline a framework for
integration of these two approaches. As an example, we develop a model in which HIV dynamics are correlated with genomics
data. For the first time, the fitness of wild type and mutated virus are assessed by means of a sequence-dependent scoring
matrix, derived from a BLOSUM matrix, that links protein sequences to growth rates of the virus in the mathematical model.
A combined bioinformatics and systems biology approach can lead to a better understanding of immune system-related diseases
where both timing and genomic information are of importance. 相似文献
54.
Rana Y. Samara Juan Carlos Monje Claus P. W. Zebitz 《Biocontrol Science and Technology》2008,18(1):75-86
Life table parameters were assessed for seven strains of Trichogramma aurosum Sugonjaev and Sorokina (Hymenoptera: Trichogrammatidae) collected in different European countries, in order to compare their performance when reared on eggs of Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) as a potential factitious host for mass-rearing. The average number of progeny per female, cumulative fertility and emergence rate did not differ significantly, whereas female longevity and sex ratio significantly differed between the seven parasitoid strains. The Danish strain survived the longest (6.05 days) and the Dutch strain survived the shortest (2.75 days). Progeny was always female-biased with varying proportions (57.7-96.7%). Survival rates started to decrease after 3 days for some of the strains studied. The mean cohort generation duration (Tc) was 11.40, 10.15, 10.62, 10.63, 9.28, 9.70 and 11.30 days for the Austrian, Luxemburgian, Belgian, French, Dutch, Danish and German strains, respectively. Population doubling time (Dt) was 4.50, 7.96, 3.56, 5.30, 5.23, 7.36 and 3.30 days, respectively. Daily intrinsic rate of increase (rm) and finite rate of increase (exp. rm) ranged between 0.087 and 0.210 and 1.091-1.233, respectively. The German strain might be a potential candidate for mass rearing and releases against the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), due to its high net reproduction rate (R0=10.65 female), a high intrinsic rate of natural increase (rm=0.210), a high finite rate of increase (exp. rm=1.23), and a short population doubling time (Dt=3.3 days). The relevance of intra- and interstrain variability as well as the usefulness of fertility life tables for pre-introductory research is discussed. 相似文献
55.
56.
Magdalena Marcińska Ewelina Po?piech Sarah Abidi Jeppe Dyrberg Andersen Margreet van den Berge ángel Carracedo Mayra Eduardoff Anna Marczakiewicz-Lustig Niels Morling Titia Sijen Ma?gorzata Skowron Jens S?chtig Denise Syndercombe-Court Natalie Weiler The EUROFORGEN-NoE Consortium Peter M. Schneider David Ballard Claus B?rsting Walther Parson Chris Phillips Wojciech Branicki 《PloS one》2015,10(5)
Androgenetic alopecia, known in men as male pattern baldness (MPB), is a very conspicuous condition that is particularly frequent among European men and thus contributes markedly to variation in physical appearance traits amongst Europeans. Recent studies have revealed multiple genes and polymorphisms to be associated with susceptibility to MPB. In this study, 50 candidate SNPs for androgenetic alopecia were analyzed in order to verify their potential to predict MPB. Significant associations were confirmed for 29 SNPs from chromosomes X, 1, 5, 7, 18 and 20. A simple 5-SNP prediction model and an extended 20-SNP model were developed based on a discovery panel of 305 males from various European populations fitting one of two distinct phenotype categories. The first category consisted of men below 50 years of age with significant baldness and the second; men aged 50 years or older lacking baldness. The simple model comprised the five best predictors: rs5919324 near AR, rs1998076 in the 20p11 region, rs929626 in EBF1, rs12565727 in TARDBP and rs756853 in HDAC9. The extended prediction model added 15 SNPs from five genomic regions that improved overall prevalence-adjusted predictive accuracy measured by area under the receiver characteristic operating curve (AUC). Both models were evaluated for predictive accuracy using a test set of 300 males reflecting the general European population. Applying a 65% probability threshold, high prediction sensitivity of 87.1% but low specificity of 42.4% was obtained in men aged <50 years. In men aged ≥50, prediction sensitivity was slightly lower at 67.7% while specificity reached 90%. Overall, the AUC=0.761 calculated for men at or above 50 years of age indicates these SNPs offer considerable potential for the application of genetic tests to predict MPB patterns, adding a highly informative predictive system to the emerging field of forensic analysis of externally visible characteristics. 相似文献
57.
Mimicry has been ascribed affiliative functions. In three experiments, we used a newly developed social-affective mimicry task (SAMT) to investigate mimicry´s modulation by emotional facial expressions (happy, angry) and ethnic group-membership (White in-group, Black out-group). Experiment 1 established the main consistent effect across experiments, which was enhanced mimicry to angry out-group faces compared to angry in-group faces. Hence the SAMT was useful for experimentally investigating the modulation of mimicry. Experiment 2 demonstrated that these effects were not confounded by general aspects of response conflict, as a Simon task resulted in different response patterns than the SAMT. Experiment 2 and pooled analysis of Experiments 1 and 2 also corroborated the finding of enhanced mimicry to angry out-group faces. Experiment 3 tested whether this effect was related to perceptions of threat, by framing angry persons as physically threatening, or not. Selective enhancement of mimicry to out-group persons framed as physically threatening confirmed this hypothesis. Further support for the role of threat was derived from implicit measures showing, in all experiments, that black persons were more strongly associated with threat. Furthermore, enhanced mimicry was consistently related to response facilitation in the execution of congruent movements. This suggests that mimicry acted as a social congruency signal. Our findings suggest that mimicry may serve as an appeasement signal in response to negative affiliative intent. This extends previous models of mimicry, which have predominantly focused on its role in reciprocating affiliation. It suggests that mimicry might not only be used to maintain and establish affiliative bonds, but also to ameliorate a negative social situation. 相似文献
58.
Industrial enzyme applications 总被引:12,自引:0,他引:12
The effective catalytic properties of enzymes have already promoted their introduction into several industrial products and processes. Recent developments in biotechnology, particularly in areas such as protein engineering and directed evolution, have provided important tools for the efficient development of new enzymes. This has resulted in the development of enzymes with improved properties for established technical applications and in the production of new enzymes tailor-made for entirely new areas of application where enzymes have not previously been used. 相似文献
59.
Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We address the question of how biofilm organization affects antibiotic susceptibility. We established Escherichia coli biofilms with differential structural organization due to the presence of IncF plasmids expressing altered forms of the transfer pili in two different biofilm model systems. The mature biofilms were subsequently treated with two antibiotics with different molecular targets, the peptide antibiotic colistin and the fluoroquinolone ciprofloxacin. The dynamics of microbial killing were monitored by viable count determination, and confocal laser microscopy. Strains forming structurally organized biofilms show an increased bacterial survival when challenged with colistin, compared to strains forming unstructured biofilms. The increased survival is due to genetically regulated tolerant subpopulation formation and not caused by a general biofilm property. No significant difference in survival was detected when the strains were challenged with ciprofloxacin. Our data show that biofilm formation confers increased colistin tolerance to cells within the biofilm structure, but the protection is conditional being dependent on the structural organization of the biofilm, and the induction of specific tolerance mechanisms. 相似文献
60.