15 research outputs found
A soft cortex is essential for asymmetric spindle positioning in mouse oocytes
At mitosis onset, cortical tension increases and cells round up, ensuring correct spindle morphogenesis and orientation. Thus, cortical tension sets up the geometric requirements of cell division. On the contrary, cortical tension decreases during meiotic divisions in mouse oocytes, a puzzling observation because oocytes are round cells, stable in shape, that actively position their spindles. We investigated the pathway leading to reduction in cortical tension and its significance for spindle positioning. We document a previously uncharacterized Arp2/3-dependent thickening of the cortical F-actin essential for first meiotic spindle migration to the cortex. Using micropipette aspiration, we show that cortical tension decreases during meiosis I, resulting from myosin-II exclusion from the cortex, and that cortical F-actin thickening promotes cortical plasticity. These events soften and relax the cortex. They are triggered by the Mos-MAPK pathway and coordinated temporally. Artificial cortex stiffening and theoretical modelling demonstrate that a soft cortex is essential for meiotic spindle positioning
The use of adjuncts to reduce seroma in open incisional hernia repair: a systematic review.
Seroma formation remains a common complication after an incisional hernia repair. The use of surgical drains is widespread, but evidence for their use and other adjuncts is limited. Our aim was to perform a systematic review of the literature on techniques used to reduce the incidence of post-operative seroma formation
Differential interactions of the formins INF2, mDia1, and mDia2 with microtubules
Three mammalian formins, although binding microtubules with high affinity, differ dramatically in their microtubule-binding mechanisms. In addition, the ability of one formin (mDia2) to bind actin is strongly inhibited by microtubules, whereas the ability of another formin (INF2) to bind microtubules is strongly inhibited by actin monomers