Pedicled Fillet of Leg Flap for Extensive Pressure Sore Coverage

Objective: Multiple large decubitus ulcers present a reconstructive challenge to the plastic surgeon. When stage IV pressure sores become recurrent or extensive, traditional flaps either have already been exhausted or would not be sufficient to cover the defect. Methods: A retrospective review was performed on all paraplegic patients who had chronic, extensive, and stage IV decubitus ulcers, and underwent reconstruction using a pedicled continuous musculocutaneous flap of the entire leg between 1998 and 2007. The extent and size of the debrided pressure sores, number of previous flap reconstructions, intraoperative blood loss, postoperative complications, and years of follow-up were all recorded. A description of the operative technique is also given. Results: Four patients underwent a total leg fillet flap in the study period, with follow-up ranging from 2 to 7 years. Indications included extensive and bilateral trochanteric, sacral, and ischial pressure sores. Complications included intraoperative blood loss and postoperative heterotopic calcification. Conclusions: The total leg fillet flap is a very large and robust flap that offers paraplegic patients coverage of extensive stage IV pressure sores of the trochanteric, sacral, and ischial areas

Sense of control and diabetes mellitus among U.S. adults: A cross-sectional analysis

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Functional plasticity of antibacterial EndoU toxins.

Bacteria use several different secretion systems to deliver toxic EndoU ribonucleases into neighboring cells. Here, we present the first structure of a prokaryotic EndoU toxin in complex with its cognate immunity protein. The contact-dependent growth inhibition toxin CdiA-CTSTECO31 from Escherichia coli STEC_O31 adopts the eukaryotic EndoU fold and shares greatest structural homology with the nuclease domain of coronavirus Nsp15. The toxin contains a canonical His-His-Lys catalytic triad in the same arrangement as eukaryotic EndoU domains, but lacks the uridylate-specific ribonuclease activity that characterizes the superfamily. Comparative sequence analysis indicates that bacterial EndoU domains segregate into at least three major clades based on structural variations in the N-terminal subdomain. Representative EndoU nucleases from clades I and II degrade tRNA molecules with little specificity. In contrast, CdiA-CTSTECO31 and other clade III toxins are specific anticodon nucleases that cleave tRNAGlu between nucleotides C37 and m2 A38. These findings suggest that the EndoU fold is a versatile scaffold for the evolution of novel substrate specificities. Such functional plasticity may account for the widespread use of EndoU effectors by diverse inter-bacterial toxin delivery systems

Thermoregulation of \u3ci\u3eEscherichia coil pap\u3c/i\u3e Transcription: H-NS is a Temperature-Dependent DNA Methylation Blocking Factor

The expression of Pap pili that facilitate the attach- ment of Escherichia coli to uroepithelial cells is shut off outside the host at temperatures below 268C. Ribo- nuclease protection analysis showed that this thermo- regulatory response was rapid as evidenced by the absence of papBA transcripts, coding for Pap pilin, after only one generation of growth at 238C. The his- tone-like nucleoid structuring protein H-NS and DNA sequences within papB were required for thermoregu- lation, but the PapB and PapI regulatory proteins were not. In vivo analysis of pap DNA methylation patterns indicated that H-NS or a factor regulated by H-NS bound within the pap regulatory region at 238C but not at 378C, as evidenced by H-NS-dependent inhibi- tion of methylation of the pap GATC sites designated GATC-I and GATC-II. These GATC sites lie upstream of the papBAp promoter and have been shown pre- viously to play a role in controlling Pap pili expression by regulating the binding of Lrp, a global regulator that is essential for activating papBAp transcription. Competitive electrophoretic mobility shift analysis showed that H-NS bound specifically to a pap DNA fragment containing the GATC-I and GATC-II sites. Moreover, H-NS blocked methylation of these pap GATC sites in vitro : H-NS blocked pap GATC methyla- tion at 1.4 mM but was unable to do so at higher con- centrations at which non-specific binding occurred. Thus, non-specific binding of H-NS to pap DNA was not sufficient to inhibit methylation of the pap GATC sites. These results suggest that the ability of H-NS to act as a methylation blocking factor is dependent upon the formation of a specific complex of H-NS with pap regulatory DNA. We hypothesize that a func- tion of H-NS such as oligomerization was altered at 238C, which enabled H-NS to repress pap gene expres- sion through the formation of a specific nucleoprotein complex

The Little Higgs from a Simple Group

We present a model of electroweak symmetry breaking in which the Higgs boson is a pseudo-Nambu-Goldstone boson. By embedding the standard model SU(2) x U(1) into an SU(4) x U(1) gauge group, one-loop quadratic divergences to the Higgs mass from gauge and top loops are canceled automatically with the minimal particle content. The potential contains a Higgs quartic coupling which does not introduce one-loop quadratic divergences. Our theory is weakly coupled at the electroweak scale, it has new weakly coupled particles at the TeV scale and a cutoff above 10 TeV, all without fine tuning. We discuss the spectrum of the model and estimate the constraints from electroweak precision measurements.Comment: 29 pages, referencing error corrected after death threats, dude remove

Triple Reassortant H3N2 Influenza A Viruses, Canada, 2005

Since January 2005, H3N2 influenza viruses have been isolated from pigs and turkeys throughout Canada and from a swine farmer and pigs on the same farm in Ontario. These are human/classical swine/avian reassortants similar to viruses that emerged in US pigs in 1998 but with a distinct human-lineage neuraminidase gene

The Nature of Starbursts : II. The Duration of Starbursts in Dwarf Galaxies

The starburst phenomenon can shape the evolution of the host galaxy and the surrounding intergalactic medium. The extent of the evolutionary impact is partly determined by the duration of the starburst, which has a direct correlation with both the amount of stellar feedback and the development of galactic winds, particularly for smaller mass dwarf systems. We measure the duration of starbursts in twenty nearby, ongoing, and "fossil" starbursts in dwarf galaxies based on the recent star formation histories derived from resolved stellar population data obtained with the Hubble Space Telescope. Contrary to the shorter times of 3-10 Myr often cited, the starburst durations we measure range from 450 - 650 Myr in fifteen of the dwarf galaxies and up to 1.3 Gyr in four galaxies; these longer durations are comparable to or longer than the dynamical timescales for each system. The same feedback from massive stars that may quench the flickering SF does not disrupt the overall burst event in our sample of galaxies. While five galaxies present fossil bursts, fifteen galaxies show ongoing bursts and thus the final durations may be longer than we report here for these systems. One galaxy shows a burst that has been ongoing for only 20 Myr; we are likely seeing the beginning of a burst event in this system. Using the duration of the starbursts, we calculate that the bursts deposited 10^(53.9)-10^(57.2) ergs of energy into the interstellar medium through stellar winds and supernovae and produced 3%-26% of the host galaxy's mass.Comment: 28 pages, 4 figure