Katanin, kinesin-13 and ataxin-2 inhibit premature interaction between maternal and paternal genomes in zygotes.

Fertilization occurs before completion of oocyte meiosis in the majority of animal species and sperm contents move long distances within zygotes of mouse and . If incorporated into the meiotic spindle, paternal chromosomes could be expelled into a polar body resulting in lethal monosomy. Through live imaging of fertilization in , we found that the microtubule disassembling enzymes, katanin and kinesin-13 limit long range movement of sperm contents and that maternal ataxin-2 maintains paternal DNA and paternal mitochondria as a cohesive unit that moves together.

Acute compression and lengthening by the Ilizarov technique for infected nonunion of the tibia with large bone defects.

Purpose: To assess the Ilizarov technique in treating large infected tibial defects by resection of the infected focus, its acute compression, and gradual distant site lengthening.

Methods: 27 men (mean age, 39 years) with infected nonunion and large bone defects of the tibia underwent complete resection of the nonunion site, debridement, sequestrectomy, lavage, and Ilizarov ring fixator application. Patients underwent acute compression of the defect site, followed by distant site metaphyseal corticotomy for simultaneous lengthening.