Ovarian carcinomas (OCs) often exhibit highly complex cytogenetic changes. Abnormal chromosome segregation at mitosis is one potential mechanism for genomic rearrangements in tumors. In this study, OCs were demonstrated to have dysfunctional short telomeres, anaphase bridging, and multipolar mitoses with supernumerary centrosomes. When normal human ovarian surface epithelial (HOSE) cells were transfected with human papilloma virus 16 e6/e7 genes and subsequently driven into telomere crisis, the same set of mitotic disturbances occurred in a distinct sequence, initiated by telomere dysfunction, followed by anaphase bridging, and then supernumerary centrosomes and multipolar mitoses. The anaphase bridges resolved either by kinetochore-spindle detachment, corresponding to whole-chromosome losses in the HOSE karyotypes, or by extensive fragmentation of intercentromeric DNA sequences, corresponding to a high frequency of pericentromeric rearrangements. At later passages, the high degree of instability at telomere crisis was moderated by telomerase expression and centrosome coalescence, ultimately leading to a level of mitotic instability that was highly similar to that in OC cell lines and to complex karyotypes that were similar to those observed in high-grade OCs. This suggests that a significant proportion of the structural chromosome changes and genomic losses in OC are caused by a specific sequence of mitotic disturbances triggered by telomere crisis. That the model did not produce any of the whole-chromosome gains observed in OC indicates that these changes develop through a different mechanism.

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This study investigated the effects of dandelion on the ruminal metabolome and microbiome in lactating dairy cows. A total of 12 mid-lactation dairy cows were selected and randomly classified into two groups, supplementing dandelion with 0 (CON) and 200 g/d per cow (DAN) above basal diet, respectively. Rumen fluid samples were collected in the last week of the trial for microbiome and metabolome analysis. The results showed that supplementation of DAN increased the concentrations of ammonia nitrogen, acetate, and butyrate significantly. The rumen bacterial community was significantly changed in the DAN group, with Bacterioidetes, Firmicutes, and Proteobacteria being the main ruminal bacterial phyla. The abundance of Ruminococcaceae_NK4A214_group, UCG_005, and Christensenellaceae_R_7_group were relatively higher, whereas that of Erysipelotrichaceae_UCG_002 and Dialister were lower in the DAN than those in the CON. Metabolomics analysis showed that the content of d-glucose, serotonin, ribulose-5-phosphate, and d-glycerate were higher in the DAN group. These metabolites were enriched in the starch and sucrose metabolism, pentose phosphate pathway, tryptophan metabolism, and glycerolipid metabolism. The ribulose-5-phosphate and d-glycerate were correlated with Ruminococcaceae_NK4A214_group, UCG_005, and Christensenellaceae_R-7_group positively. This study demonstrated that the supplementation of dandelion impacts the ruminal microorganisms and metabolites in a way that rumen fermentation was enhanced in lactating dairy cows.