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The immunophenotype of HT29 human colon cancer cells implanted into severe combined immunodeficient mice was assessed in primary
tumours and their metastases in the lungs using an indirect immunohistochemical method. After primary tumours were surgically
removed, the metastases were given time to develop, thus paralleling the clinical situation. While vimentin was negative in
both primary and secondary tumours, E-cadherin was present as membrane-bound labelling in the primary tumours only. Whereas
the markers p53, MIB1, PCNA and CEA were consistently positive in both primary and metastatic tumours, CD44 variant 6 and
CA125 were negative in metastases but positive in the primary tumours. There was a significant increase in the percentage
of cells labelled for p53 in the primary tumours compared with the metastases. For the proliferation markers, there was no
significant difference in labelling between primary tumours and metastases for MIB1. Of the cytokeratins examined, CK 20 gave
the strongest and most consistent reaction in both primary and secondary tumours. The results indicate that, for certain immunohistochemical
markers, results are the same in both primary tumours and metastases. Hence, in these cases, antigens that are expressed on
the primary tumour as well as on the metastases can serve as target molecules for immunologically based forms of treatment
of metastases.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
33.
Transcriptional initiation and 5' termini of yeast mitochondrial RNA 总被引:27,自引:0,他引:27
D Levens B Ticho E Ackerman M Rabinowitz 《The Journal of biological chemistry》1981,256(10):5226-5232
34.
A likelihood approach for comparing synonymous and nonsynonymous nucleotide substitution rates, with application to the chloroplast genome 总被引:29,自引:24,他引:5
A model of DNA sequence evolution applicable to coding regions is
presented. This represents the first evolutionary model that accounts for
dependencies among nucleotides within a codon. The model uses the codon, as
opposed to the nucleotide, as the unit of evolution, and is parameterized
in terms of synonymous and nonsynonymous nucleotide substitution rates. One
of the model's advantages over those used in methods for estimating
synonymous and nonsynonymous substitution rates is that it completely
corrects for multiple hits at a codon, rather than taking a parsimony
approach and considering only pathways of minimum change between homologous
codons. Likelihood-ratio versions of the relative-rate test are constructed
and applied to data from the complete chloroplast DNA sequences of Oryza
sativa, Nicotiana tabacum, and Marchantia polymorpha. Results of these
tests confirm previous findings that substitution rates in the chloroplast
genome are subject to both lineage-specific and locus-specific effects.
Additionally, the new tests suggest tha the rate heterogeneity is due
primarily to differences in nonsynonymous substitution rates. Simulations
help confirm previous suggestions that silent sites are saturated, leaving
no evidence of heterogeneity in synonymous substitution rates.
相似文献
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Yulia Anita Muhammad Radifar Leonardus BS Kardono Muhammad Hanafi Enade P Istyastono 《Bioinformation》2012,8(19):901-906
Eugenol is an essential oil mainly found in the buds and leaves of clove (Syzygium aromaticum (L.) Merrill and Perry), which has
been reported to have activity on inhibition of cell proliferation and apoptosis induction in human MCF-7 breast cancer cells. This
biological activity is correlated to its activity as an estrogen receptor antagonist. In this article, we present the construction and
validation of structure-based virtual screening (SBVS) protocols to identify the potent estrogen receptor α (ER) antagonists. The
selected protocol, which gave acceptable enrichment factors as a virtual screening protocol, subsequently used to virtually screen
eugenol, its analogs and their dimers. Based on the virtual screening results, dimer eugenol of 4-[4-hydroxy-3-(prop-2-en-1-
yl)phenyl]-2-(prop-2-en-1-yl)phenol is recommended to be developed further in order to discover novel and potent ER antagonists. 相似文献
38.
Climate change poses an unprecedented threat to biodiversity worldwide. Consequently, unrecognised taxa may not receive adequate conservation attention to survive. We used molecular and morphological data to address the challenge of species delimitation within the genus Schilbe. The presence or absence of an adipose fin and distribution based on east-flowing, conceivably faster-flowing, or west-flowing, probably more slow-flowing, river systems were considered. Distinctive geographic patterns in genetic variation within southern, eastern, and western African populations were revealed. Particularly, the South African population is distinct from those of Namibia, Botswana and Nigeria. No individuals with rudimentary adipose fins were found at any locality, but specimens from three localities either had or did not have adipose fins. These mixed occurrences are suspected to be a result of human interventions, and that the presence of rudimentary adipose fins in the east African species could be an adaptive feature that serves to stabilise these fish in faster currents. In addition, the genetic divergence observed among African silver catfish from geographically isolated river systems is conceivably the result of micro-evolutionary adaptive responses to different environmental conditions. Collectively, these results distinguish S. depressirostris from S. intermedius. 相似文献
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Dennis V Pedersen Gregers R Andersen Dennis V Pedersen Lubka Roumenina Rasmus K Jensen Trine AF Gadeberg Chiara Marinozzi Capucine Picard Tania Rybkine Steffen Thiel Uffe BS Sørensen Cordula Stover Veronique Fremeaux-Bacchi Gregers R Andersen 《The EMBO journal》2017,36(8):1084-1099
Properdin (FP) is an essential positive regulator of the complement alternative pathway (AP) providing stabilization of the C3 and C5 convertases, but its oligomeric nature challenges structural analysis. We describe here a novel FP deficiency (E244K) caused by a single point mutation which results in a very low level of AP activity. Recombinant FP E244K is monomeric, fails to support bacteriolysis, and binds weakly to C3 products. We compare this to a monomeric unit excised from oligomeric FP, which is also dysfunctional in bacteriolysis but binds the AP proconvertase, C3 convertase, C3 products and partially stabilizes the convertase. The crystal structure of such a FP-convertase complex suggests that the major contact between FP and the AP convertase is mediated by a single FP thrombospondin repeat and a small region in C3b. Small angle X-ray scattering indicates that FP E244K is trapped in a compact conformation preventing its oligomerization. Our studies demonstrate an essential role of FP oligomerization in vivo while our monomers enable detailed structural insight paving the way for novel modulators of complement. 相似文献