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21.
JB Parentes-Vieira PV Lopes-Costa CG Pires AR dos Santos JD Pereira-Filho BB da Silva 《International Seminars in Surgical Oncology : ISSO》2007,4(1):22
Background
The objective of this study was to evaluate angiogenesis according to CD34 antigen expression in estrogen receptor (ER)-positive and negative breast carcinomas.Methods
This study comprised 64 cases of infiltrating ductal carcinoma in postmenopausal women divided into two groups: Group A: ER-positive, n = 35; and Group B: ER-negative, n = 29. The anti-CD34 monoclonal antibody was used as a marker for endothelial cells. Microvessel count was carried out in 10 fields per slide using a 40× objective lens (magnification 400×). Statistical analysis of the data was performed using Student's t-test (p < 0.05).Results
The mean number of vessels stained with the anti-CD34 antibody in the estrogen receptor-positive and negative tumors was 23.51 ± 1.15 and 40.24 ± 0.42, respectively. The number of microvessels was significantly greater in the estrogen receptor-negative tumors (p < 0.001).Conclusion
ER-negative tumors have significantly greater CD34 antigen expression compared to ER-positive tumors.22.
Sperandio D Tai VW Lohman J Hirschbein B Mendonca R Lee CS Spencer JR Janc J Nguyen M Beltman J Sprengeler P Scheerens H Lin T Liu L Gadre A Kellogg A Green MJ McGrath ME 《Bioorganic & medicinal chemistry letters》2006,16(15):4085-4089
The synthesis of novel [1,2,4]oxadiazoles and their structure-activity relationship (SAR) for the inhibition of tryptase and related serine proteases is presented. Elaboration of the P'-side afforded potent, selective, and orally bioavailable tryptase inhibitors. 相似文献
23.
Substitution bias, rapid saturation, and the use of mtDNA for nematode systematics 总被引:13,自引:0,他引:13
Only relatively recently have researchers turned to molecular methods for
nematode phylogeny reconstruction. Thus, we lack the extensive literature
on evolutionary patterns and phylogenetic usefulness of different DNA
regions for nematodes that exists for other taxa. Here, we examine the
usefulness of mtDNA for nematode phylogeny reconstruction and provide data
that can be used for a priori character weighting or for parameter
specification in models of sequence evolution. We estimated the
substitution pattern for the mitochondrial ND4 gene from intraspecific
comparisons in four species of parasitic nematodes from the family
Trichostrongylidae (38-50 sequences per species). The resulting pattern
suggests a strong mutational bias toward A and T, and a lower
transition/transversion ratio than is typically observed in other taxa. We
also present information on the relative rates of substitution at first,
second, and third codon positions and on relative rates of saturation of
different types of substitutions in comparisons ranging from intraspecific
to interordinal. Silent sites saturate extremely quickly, presumably owing
to the substitution bias and, perhaps, to an accelerated mutation rate.
Results emphasize the importance of using only the most closely related
sequences in order to infer patterns of substitution accurately for
nematodes or for other taxa having strongly composition-biased DNA. ND4
also shows high amino acid polymorphism at both the intra- and
interspecific levels, and in higher level comparisons, there is evidence of
saturation at variable amino acid sites. In general, we recommend using
mtDNA coding genes only for phylogenetics of relatively closely related
nematode species and, even then, using only nonsynonymous substitutions and
the more conserved mitochondrial genes (e.g., cytochrome oxidases). On the
other hand, the high substitution rate in genes such as ND4 should make
them excellent for population genetics studies, identifying cryptic
species, and resolving relationships among closely related congeners when
other markers show insufficient variation.
相似文献
24.
Phylogeny of the Drosophila saltans species group based on combined analysis of nuclear and mitochondrial DNA sequences 总被引:2,自引:0,他引:2
Nucleotide sequences from two nuclear loci, alcohol dehydrogenase and
internal transcribed spacer-1 of the nuclear ribosomal DNA repeats, and two
mitochondrial genes, cytochrome oxidase I and cytochrome oxidase II, were
determined from nine species in the Drosophila saltans species group. The
partition homogeneity test and partitioned Bremer support were used to
measure incongruence between phylogenetic hypotheses generated from
individual partitions. Individual loci were generally congruent with each
other and consistent with the previously proposed morphological hypothesis,
although they differed in level of resolution. Since extreme conflict
between partitions did not exist, the data were combined and analyzed
simultaneously. The total evidence method gave a more resolved and highly
supported phylogeny, as indicated by bootstrap proportions and decay
indices, than did any of the individual analyses. The cordata and elliptica
subgroups, considered to have diverged early in the history of the D.
saltans group, were sister taxa to the remainder of the saltans group. The
sturtevanti subgroup, represented by D. milleri and D. sturtevanti,
occupies an intermediate position in this phylogeny. The saltans and
parasaltans subgroups are sister clades and occupy the most recently
derived portion of the phylogeny. As with previous morphological studies,
phylogenetic relationships within the saltans subgroup were not
satisfactorily resolved by the molecular data.
相似文献
25.
Nucleotide sequence comparisons were used to investigate the evolution of P
transposable elements and the possibility that horizontal transfer has
played a role in their occurrence in natural populations of Drosophila and
other Diptera. The phylogeny of P elements was examined using published
sequences from eight dipteran taxa and a new, partial sequence from
Scaptomyza elmoi. The results from a number of different analyses are
highly consistent and reveal a P-element phylogeny that contradicts the
phylogeny of the species. At least three instances of horizontal transfer
are necessary to explain this incongruence, but other explanations cannot
be ruled out at this time.
相似文献
26.
27.
M. J. Anderson D. Cacela D. Beltman S. J. Teh M. S. Okihiro D. E. Hinton 《Biomarkers》2013,18(5):371-393
Smallmouth bass (Micropterus dolomieu) were collected to quantify the nature and prevalence of biomarker responses, including biochemical indices, toxicopathic lesions and general health indices, among fish collected from polychlorinated biphenyl (PCB)-contaminated and nearby uncontaminated reaches of the Kalamazoo River, Michigan, USA. Blood and tissue samples (gill, liver, spleen, head kidney, trunk kidney, thyroid and gonads) were collected and preserved at necropsy for biochemical and histological analyses. The body condition factor and liver somatic index were significantly lower in fish collected from the downstream, contaminated site. Plasma vitellogenin was not detected in male fish collected from either site. Liver ethoxyresorufin-O-deethylase activity and liver and spleen superoxide dismutase activity were significantly depressed in fish collected from the downstream site. Significant toxicopathic lesions such as glycogen depletion, enhanced macrophage aggregates, hepatic foci of cellular alteration (i.e. preneoplastic lesions) and neoplasia were also detected in the liver of fish collected from the downstream site. This study indicates that many of the biochemical and histopathological biomarker responses were associated with liver and body tissue PCB concentrations. Taken together, the biomarkers of exposure and effect strongly suggest that fish within the downstream site are adversely affected by PCBs and other chemical stressors. 相似文献
28.
Thomas van den Akker Jogchum Beltman Joey Leyten Beatrice Mwagomba Tarek Meguid Jelle Stekelenburg Jos van Roosmalen 《PloS one》2013,8(1)
Introduction
WHO proposes a set of organ-failure based criteria for maternal near miss. Our objective was to evaluate what implementation of these criteria would mean for the analysis of a cohort of 386 women in Thyolo District, Malawi, who sustained severe acute maternal morbidity according to disease-based criteria.Methods and Findings
A WHO Maternal Near Miss (MNM) Tool, created to compare disease-, intervention- and organ-failure based criteria for maternal near miss, was completed for each woman, based on a review of all available medical records. Using disease-based criteria developed for the local setting, 341 (88%) of the 386 women fulfilled the WHO disease-based criteria provided by the WHO MNM Tool, 179 (46%) fulfilled the intervention-based criteria, and only 85 (22%) the suggested organ-failure based criteria.Conclusions
In this low-resource setting, application of these organ-failure based criteria that require relatively sophisticated laboratory and clinical monitoring underestimates the occurrence of maternal near miss. Therefore, these criteria and the suggested WHO approach may not be suited to compare maternal near miss across all settings. 相似文献29.
30.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5