Axon guidance requires coordinated remodeling of actin and microtubule polymers. Using a genetic screen, we identified the microtubule-associated protein Orbit/MAST as a partner of the Abelson (Abl) tyrosine kinase. We find identical axon guidance phenotypes in orbit/MAST and Abl mutants at the midline, where the repellent Slit restricts axon crossing. Genetic interaction and epistasis assays indicate that Orbit/MAST mediates the action of Slit and its receptors, acting downstream of Abl. We find that Orbit/MAST protein localizes to Drosophila growth cones. Higher-resolution imaging of the Orbit/MAST ortholog CLASP in Xenopus growth cones suggests that this family of microtubule plus end tracking proteins identifies a subset of microtubules that probe the actin-rich peripheral growth cone domain, where guidance signals exert their initial influence on cytoskeletal organization. These and other data suggest a model where Abl acts as a central signaling node to coordinate actin and microtubule dynamics downstream of guidance receptors.

Single crystals of calcite with regular patterned surfaces comprising close-packed arrays of hemispherical cavities or domes were produced by crystallization on colloidal monolayers or PDMS replicas of these monolayers, respectively. Perfect replication of the substrate topography was achieved for all colloidal particles, irrespective of their size and surface chemistry when the substrate geometry permitted unrestricted ion flow to the growing crystal. This work demonstrates that crystallization within a mould provides a very general route to producing single crystals with curved surfaces and unusual morphologies and that such patterning can be applied from the micro- to the nanoscale.

Infertility affects 1 in 7 couples in the UK. Tubal patency tests are an important part of infertility investigations. We conducted this observational study to determine the interval between a laparoscopy and dye test and spontaneous conception in women with unexplained infertility and minimal to mild endometriosis and pelvic adhesions treated during the procedure. The clinical records of 432 women coded as having had a laparoscopy and dye test or laparoscopy and tubal patency test between April 2007 and March 2010 were retrieved from a computerised theatre database. Pregnancies were identified through a computerised maternity booking system. Spontaneous pregnancies were recorded in 162 women following surgery (37.5%). There was a significant difference in conception rates between women with unexplained infertility and those with minor abnormalities treated at the time of diagnosis (43% vs. 58%, p = 0.019). Eighty percent of women who conceived spontaneously achieved their pregnancy within 18 months of surgery. A high proportion of women with unexplained infertility or minor abnormalities treated at the time of a laparoscopy and dye test conceived spontaneously within 12 months.

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