Cell cycle checkpoints enhance genetic fidelity by causing arrest at specific stages of the cell cycle when previous events have not been completed. The tumor suppressor p53 has been implicated in a G1 checkpoint. To investigate whether p53 also participates in a mitotic checkpoint, cultured fibroblasts from p53-deficient mouse embryos were exposed to spindle inhibitors. The fibroblasts underwent multiple rounds of DNA synthesis without completing chromosome segregation, thus forming tetraploid and octaploid cells. Deficiency of p53 was also associated with the development of tetraploidy in vivo. These results suggest that murine p53 is a component of a spindle checkpoint that ensures the maintenance of diploidy.

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Laparoscopic hernioplasty is superior to tension-free open herniorrhaphy in terms of postoperative pain and rehabilitation.

Pharyngeal reflux is significantly more prevalent in patients with posterior laryngitis than in healthy control subjects. Moreover, a certain degree of pharyngeal reflux appears to be a normal phenomenon. The most common laryngeal finding in patients with posterior laryngitis is thickening or edema of the posterior wall of the glottis. GEPR does not yield specific laryngeal symptoms. Thus, it is unreliable to base the reflux diagnosis on symptoms alone.