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21.
We present an updated account of breast cancer treatment and of progress toward “precision” cancer therapy; we focus on new developments in diagnostic molecular pathology and breast cancer that have emerged during the past 2 years. Increasing awareness of new prognostic and predictive methodologies, and introduction of next generation sequencing has increased understanding of both tumor biology and clinical behavior, which offers the possibility of more appropriate therapeutic choices. It remains unclear which of these testing methodologies provides the most informative and cost-effective actionable results for predictive and prognostic pathology. It is likely, however, that an integrated “step-wise” approach that uses the traditional clinical-pathologic paradigms coordinated with molecular characterization of breast tumor tissue, will offer the most comprehensive and cost-effective options for individualized, “precision” therapy for patients with breast cancer.  相似文献   
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Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 106 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to be more beneficial for treating breast cancer than donkey milk.  相似文献   
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The silkmoth chorion has provided a stimulating model for the study of evolution and developmental regulation of gene families. Previous attempts at inferring relationships among chorion sequences have been based on pairwise comparisons of overall similarity, a potentially problematic approach. To remedy this, we identified the alignable regions of low sequence variability and then analyzed this restricted database by parsimony and neighbor-joining methods. At the deepest level, the chorion sequence tree is split into two branches, called "alpha" and "beta." Within each branch, early- and late-expressing genes each constitute monophyletic groups, while the situation with middle-expressing genes remains uncertain. The HcB gene family appears to be the most basal beta-branch group, but this conclusion is qualified because the effect of gene conversion on branching order is unknown. Previous studies by Eickbush and colleagues have strongly suggested that ErA, HcA, and HcB families undergo gene conversion within a gene family, whereas the ErB family does not. The occurrence of conversion correlates with a particular tree structure; namely, branch lengths are much greater at the base of the family than at higher internodes and terminal branches. These observations raise the possibility that chorion gene families are defined by gene conversion events (reticulate evolution) rather than by descent with modification (synapomorphy).   相似文献   
24.

Background  

Recently, a Risk Assessment methodology was applied to animal welfare issues in a report of the European Food Safety Authority (EFSA) on intensively housed calves.  相似文献   
25.

Background

BRCA protein interacts with at least 13 different proteins that have been implicated with cancer susceptibility and loss of BRCA function is correlated to sensitivity to DNA crosslinking agents in preclinical models.

Results

BRCA2 methylation frequency was 44%, p53 Pro22 allele frequency was 32% and heterozygous frequency of Arg/Pro72 genotype was 60% which could be associated as risk factor for metastasis (p = 0.046 OR = 4.190). Regarding to polymorphism of codon 249 the frequency of Arg249 allele presented 82% which was considered not statistically significant.

Conclusions

There was not statistical significance to BRCA2 promoter methylation with any parameters chosen. However, our findings suggest that patients who present heterozygous genotype at codon 72 of p53 gene may have a major susceptibility to any type of metastasis and this could serve as potential auxiliary biomarker for poor prognosis.  相似文献   
26.
Microbial adaptation to environmental conditions is a complex process, including acquisition of positive traits through horizontal gene transfer or the modification of existing genes through duplication and/or mutation. In this study, we examined the adaptation of a Pseudomonas fluorescens isolate (R124) from the nutrient-limited mineral environment of a silica cave in comparison with P. fluorescens isolates from surface soil and the rhizosphere. Examination of metal homeostasis gene pathways demonstrated a high degree of conservation, suggesting that such systems remain functionally similar across chemical environments. The examination of genomic islands unique to our strain revealed the presence of genes involved in carbohydrate metabolism, aromatic carbon metabolism, and carbon turnover, confirmed through phenotypic assays, suggesting the acquisition of potentially novel mechanisms for energy metabolism in this strain. We also identified a twitching motility phenotype active at low-nutrient concentrations that may allow alternative exploratory mechanisms for this organism in a geochemical environment. Two sets of candidate twitching motility genes are present within the genome, one on the chromosome and one on a plasmid; however, a plasmid knockout identified the functional gene as being present on the chromosome. This work highlights the plasticity of the Pseudomonas genome, allowing the acquisition of novel nutrient-scavenging pathways across diverse geochemical environments while maintaining a core of functional stress response genes.  相似文献   
27.
A 522-base-long Y-chromosomal sequence was isolated from a BALB/c genomic library and was designated "BF046." It is repeated about 200 times in the male genome, and a difference was detected between the Mus musculus musculus and the M. m. domesticus type Y chromosomes. BF046- related sequences were present over the entire length of the Y chromosome as visualized by in situ hybridization. Southern blot analysis against DNAs isolated from eight species in the genus Mus showed that BF046-related sequences were amplified in the Y chromosomes of three closely related species: M. musculus, M. spicilegus, and M. spretus. To gain insight into the stability of the BF046 sequence family, we isolated 18 additional clones from these three mouse species and compared their sequences. The M. musculus sequences differed from the M. spicilegus and M. spretus sequences by two indels. The remaining parts of the sequences were very similar, but both parsimony and distance-based analytical methods divided the sequences into the same four subgroups, with each species having its own subgroup(s). Thus, the Y chromosomes of M. musculus, M. spicilegus, and M. spretus can be distinguished from one another.   相似文献   
28.
The R-spondin protein family   总被引:1,自引:0,他引:1  
The four vertebrate R-spondin proteins are secreted agonists of the canonical Wnt/β-catenin signaling pathway. These proteins are approximately 35 kDa, and are characterized by two amino-terminal furin-like repeats, which are necessary and sufficient for Wnt signal potentiation, and a thrombospondin domain situated more towards the carboxyl terminus that can bind matrix glycosaminoglycans and/or proteoglycans. Although R-spondins are unable to initiate Wnt signaling, they can potently enhance responses to low-dose Wnt proteins. In humans, rare disruptions of the gene encoding R-spondin1 cause a syndrome of XX sex reversal (phenotypic male), palmoplantar keratosis (a thickening of the palms and soles caused by excess keratin formation) and predisposition to squamous cell carcinoma of the skin. Mutations in the gene encoding R-spondin4 cause anonychia (absence or hypoplasia of nails on fingers and toes). Recently, leucine-rich repeat-containing G-protein-coupled receptor (Lgr)4, Lgr5 and Lgr6, three closely related orphans of the leucine-rich repeat family of G-protein-coupled receptors, have been identified as receptors for R-spondins. Lgr5 and Lgr6 are markers for adult stem cells. Because R-spondins are potent stimulators of adult stem cell proliferation in vivo and in vitro, these findings might guide the therapeutic use of R-spondins in regenerative medicine.  相似文献   
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