Gene targeting for O -methyltransferase genes, mycE and mycF , on the chromosome of Micromonospora griseorubida producing mycinamicin with a disruption cassette containing the bacteriophage φC31 attB attachment site

Mycinamicin, a 16-membered macrolide antibiotic produced by Micromonospora griseorubida , comprises a macrolactone and two deoxysugars: desosamine and mycinose. Mycinose is synthesized through two modification steps: the methylation of 6-deoxyallose in mycinamicin VI and of javose in mycinamicin III. To confirm the role of mycE and mycF genes in mycinamicin biosynthesis in M. griseorubida , disruption mutants of mycE and mycF were constructed by disruption plasmids containing attB in the disruption cassette FRT -neo-oriT- FRT -attB for the integration of φC31-derivative vector plasmids; the disruption mutants were complemented through the integration of pSET152 derivatives containing intact mycE or mycF into the artificially inserted attB site. These disruption mutants did not produce mycinamicin II, but mainly accumulated mycinamicins VI and III, indicating that MycE and MycF methylated the C2″-OH group of 6-deoxyallose in mycinamicin VI and the C3″-OH group of C2″-methylated 6-deoxyallose in mycinamicin III, respectively. The complemented strains of mycE and mycF recovered the mycinamicin II productivity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79258/1/j.1574-6968.2010.01899.x.pd

Efficacy and Optimal Timing of TEVAR for Type B-AD

Objectives: To determine the efficacy and the optimal timing of thoracic endovascular aortic repair (TEVAR) for closing the primary entry in uncomplicated patients with chronic type B aortic dissection and a patent false lumen (FL). Methods: Thirteen patients underwent TEVAR for aortic dissection between 2008 and 2012. These patients had chronic dissection with a patent FL and expansion of the aorta. Early TEVAR was performed for five patients within 1–7 months from the index dissection (TEVAR-EC group) and delayed TEVAR was performed for eight patients within 1–16 years (TEVAR-DC group). Changes in the diameters and volumes of the true lumen (TL) and FL and the aortic remodeling were assessed by multidetector computed tomography for 3 years after TEVAR. Results: The reduction rate of FL in the thoracic aorta was notably higher in the TEVAR-EC group than in the TEVAR-DC group regardless of the presence or absence of distal retrograde flow. There was a significant TL expansion despite different timings of TEVAR. Conclusions: Early TEVAR resulted in good prognosis and preferable aortic remodeling in uncomplicated patients with chronic type B aortic dissection and a patent FL, and we recommend early TEVAR within seven months after the index dissection

Regulation of interkinetic nuclear migration by cell cycle-coupled active and passive mechanisms in the developing brain

In proliferating neural epithelia, cells undergo interkinetic nuclear migration: stereotyped cell cycle-dependent movements in the apico-basal plane. The microtubule-binding protein Tpx2 is here shown to regulate the G2-phase basal-to-apical migration, while passive displacement effects are responsible for basally directed movements