Protein synthesis and transport in the regenerating goldfish visual system

The nature of the proteins synthesized in the goldfish retina and axonally transported to the tectum during optic nerve regeneration has been examined. Electrophoretic analysis of labeled soluble retinal proteins by fluorography verified our previous observation of a greatly enhanced synthesis of the microtubule subunits. In addition, labeling of a tubulin-like protein in the retinal particulate fraction was also increased during regeneration. Like soluble tubulin, the particulate material had an apparent MW of 53–55K and could be tyrosylated in the presence of cycloheximide and [ 3 H]tyrosine. Comparison of post-crush and normal retinal proteins by two-dimensional gel electrophoresis also revealed a marked enhancement in the labeling of two acidic 68–70K proteins. Analysis of proteins slowly transported to the optic tectum revealed changes following nerve crush similar to those observed in the retina, with enhanced labeling of both soluble and particulate tubulin and of 68–70K polypeptides. The most striking change in the profile of rapidly transported protein was the appearance of a labeled 45K protein which was barely detectable in control fish.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45430/1/11064_2004_Article_BF00965529.pd

Back on track – On the role of the microtubule for kinesin motility and cellular function

The evolution of cytoskeletal filaments (actin- and intermediate-filaments, and the microtubules) and their associated motor- and non-motor-proteins has enabled the eukaryotic cell to achieve complex organizational and structural tasks. This ability to control cellular transport processes and structures allowed for the development of such complex cellular organelles like cilia or flagella in single-cell organisms and made possible the development and differentiation of multi-cellular organisms with highly specialized, polarized cells. Also, the faithful segregation of large amounts of genetic information during cell division relies crucially on the reorganization and control of the cytoskeleton, making the cytoskeleton a key prerequisite for the development of highly complex genomes. Therefore, it is not surprising that the eukaryotic cell continuously invests considerable resources in the establishment, maintenance, modification and rearrangement of the cytoskeletal filaments and the regulation of its interaction with accessory proteins. Here we review the literature on the interaction between microtubules and motor-proteins of the kinesin-family. Our particular interest is the role of the microtubule in the regulation of kinesin motility and cellular function. After an introduction of the kinesin–microtubule interaction we focus on two interrelated aspects: (1) the active allosteric participation of the microtubule during the interaction with kinesins in general and (2) the possible regulatory role of post-translational modifications of the microtubule in the kinesin–microtubule interaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42588/1/10974_2005_Article_9052.pd

Arthroscopic Versus Open Anterior Shoulder Stabilization: A Prospective Randomized Clinical Trial With 15-Year Follow-up With an Assessment of the Glenoid Being “On-Track” and “Off-Track” as a Predictor of Failure

Background: Recent studies have demonstrated equivalent short-term results when comparing arthroscopic versus open anterior shoulder stabilization. However, none have evaluated the long-term clinical outcomes of patients after arthroscopic or open anterior shoulder stabilization, with inclusion of an assessment of preoperative glenoid tracking. Purpose: To compare long-term clinical outcomes of patients with recurrent anterior shoulder instability randomized to open and arthroscopic stabilization groups. Additionally, preoperative magnetic resonance imaging (MRI) studies were used to assess whether the shoulders were “on-track” or “off-track” to ascertain a prediction of increased failure risk. Study Design: Randomized controlled trial; Level of evidence, 1. Methods: A consecutive series of 64 patients with recurrent anterior shoulder instability were randomized to receive either arthroscopic or open stabilization by a single surgeon. Follow-up assessments were performed at minimum 15-year follow-up using established postoperative evaluations. Clinical failure was defined as any recurrent dislocation postoperatively or subjective instability. Preoperative MRI scans were obtained to calculate the glenoid track and designate shoulders as on-track or off-track. These results were then correlated with the patients’ clinical results at their latest follow-up. Results: Of 64 patients, 60 (28 arthroscopic and 32 open) were contacted or examined for follow-up (range, 15-17 years). The mean age at the time of surgery was 25 years (range, 19-42 years), while the mean age at the time of this assessment was 40 years (range, 34-57 years). The rates of arthroscopic and open long-term failure were 14.3% (4/28) and 12.5% (4/32), respectively. There were no differences in subjective shoulder outcome scores between the treatment groups. Of the 56 shoulders, with available MRI studies, 8 (14.3%) were determined to be off-track. Of these 8 shoulders, there were 2 surgical failures (25.0%; 1 treated arthroscopically, 1 treated open). In the on-track group, 6 of 48 had failed surgery (12.5%; 3 open, 3 arthroscopic [ P = .280]). Conclusion: Long-term clinical outcomes were comparable at 15 years postoperatively between the arthroscopic and open stabilization groups. The presence of an off-track lesion may be associated with a higher rate of recurrent instability in both cohorts at long-term follow-up; however, this study was underpowered to verify this situation. </jats:sec

Studies in non-linear modeling

http://deepblue.lib.umich.edu/bitstream/2027.42/3514/5/bab2954.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/3514/4/bab2954.0001.001.tx

Studies in Radar Cross-Sections - XLV. Studies in non-linear modeling - II

http://deepblue.lib.umich.edu/bitstream/2027.42/21213/2/rl2088.0001.001.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/21213/1/rl2088.0001.001.tx

Resolving Enhanced Mn2+ Luminescence near the Surface of CsPbCl3 with Time-Resolved Cathodoluminescence Imaging.

Mn2+ doping of lead halide perovskites has garnered recent interest because it produces stable orange luminescence in tandem with perovskite emission. Here, we observe enhanced Mn2+ luminescence at the edges of Mn2+-doped CsPbCl3 perovskite microplates and suggest an explanation for its origin using the high spatiotemporal resolution of time-resolved cathodoluminescence (TRCL) imaging. We reveal two luminescent decay components that we attribute to two different Mn2+ populations. While each component appears to be present both near the surface and in the bulk, the origin of the intensity variation stems from a higher proportion of the longer lifetime component near the perovskite surface. We suggest that this higher emission is caused by an increased probability of electron-hole recombination on Mn2+ near the perovskite surface due to an increased trap concentration there. This observation suggests that such surface features have yet untapped potential to enhance emissive properties via control of surface-to-volume ratio

Resolving Enhanced Mn2+ Luminescence near the Surface of CsPbCl3 with Time-Resolved Cathodoluminescence Imaging.

Mn2+ doping of lead halide perovskites has garnered recent interest because it produces stable orange luminescence in tandem with perovskite emission. Here, we observe enhanced Mn2+ luminescence at the edges of Mn2+-doped CsPbCl3 perovskite microplates and suggest an explanation for its origin using the high spatiotemporal resolution of time-resolved cathodoluminescence (TRCL) imaging. We reveal two luminescent decay components that we attribute to two different Mn2+ populations. While each component appears to be present both near the surface and in the bulk, the origin of the intensity variation stems from a higher proportion of the longer lifetime component near the perovskite surface. We suggest that this higher emission is caused by an increased probability of electron-hole recombination on Mn2+ near the perovskite surface due to an increased trap concentration there. This observation suggests that such surface features have yet untapped potential to enhance emissive properties via control of surface-to-volume ratio