Perspectives on telemedicine to improve stroke treatment.

Stroke is the number three cause of death and the most common cause of adult disability in the United States. Few patients receive the only established effective therapy, intravenous tissue plasminogen activator. Failure to treat may occur due to several reasons, a crucial one being the lack of acute neurologic coverage, particularly in rural settings. In this article we review the difficulties encountered by patients needing immediate care to access stroke specialists. To overcome this delay in patient care, telemedicine technology for acute stroke care is recommended. We track the emergence and evolution of "telestroke" from initial telephone consultation, to point-to-point, hub-and-spoke networks, to web-based site-independent telestroke systems. We detail the emerging evidence for the safety and efficacy of these remote telestroke systems through observational studies (TEMPiS and REACH). Lastly, we discuss areas where telestroke could potentially expand to provide more complete stroke care beyond the acute thrombolysis phase, as well as its potential to improve clinical research and the need for cost-effective research. We conclude that telestroke is currently the most practical solution to any setback faced by stroke specialists with respect to low thrombolytic rates.

Molybdenum disulfide nanowires and nanoribbons by electrochemical/chemical synthesis.

Molybdenum disulfide nanowires and nanoribbons have been synthesized by a two-step, electrochemical/chemical synthetic method. In the first step, MoO(x) wires (a mixture of MoO(2) and MoO(3)) were electrodeposited size-selectively by electrochemical step-edge decoration on a highly oriented pyrolytic graphite (HOPG) surface. Then, MoO(x) precursor wires were converted to MoS(2) by exposure to H(2)S either at 500-700 degrees C, producing "low-temperature" or LT MoS(2) nanowires that were predominantly 2H phase, or above 800 degrees C producing "high-temperature" or HT MoS(2) ribbons that were predominantly 3R phase. The majority of these MoS(2) wires and ribbons were more than 50 microm in length and were organized into parallel arrays containing hundreds of wires or ribbons. MoS(2) nanostructures were characterized by X-ray photoelectron spectroscopy, scanning and transmission electron microscopy, selected area electron diffraction, X-ray diffraction, UV-visible absorption spectrometry, and Raman spectroscopy. HT and LT MoS(2) nanowires were structurally distinct: LT MoS(2) wires were hemicylindrical in shape and nearly identical in diameter to the MoO(x) precursor wires from which they were derived. LT MoS(2) wires were polycrystalline, and the internal structure consisted of many interwoven, multilayer strands of MoS(2); HT MoS(2) ribbons were 50-800 nm in width and 3-100 nm thick, composed of planar crystallites of 3R-MoS(2). These layers grew in van der Waals contact with the HOPG surface so that the c-axis of the 3R-MoS(2) unit cell was oriented perpendicular to the plane of the graphite surface. Arrays of MoS(2) wires and ribbons could be cleanly separated from the HOPG surface and transferred to glass for electrical and optical characterization. Optical absorption measurements of HT MoS(2) nanoribbons reveal a direct gap near 1.95 eV and two exciton peaks, A1 and B1, characteristic of 3R-MoS(2). These exciton peaks shifted to higher energy by up to 80 meV as the wire thickness was decreased to 7 nm (eleven MoS(2) layers). The energy shifts were proportional to 1/ L( parallel)(2), and the effective masses were calculated. Current versus voltage curves for both LT and HT MoS(2) nanostructures were probed as a function of temperature from -33 degrees C to 47 degrees C. Conduction was ohmic and mainly governed by the grain boundaries residing along the wires. The thermal activation barrier was found to be related to the degree of order of the crystallites and can be tuned from 126 meV for LT nanowires to 26 meV for HT nanoribbons.

Comminuted fractures of the iliac wing.

PURPOSE: Comminuted iliac fractures are uncommon and difficult to treat. The purpose of this study is to further delineate the fractures, to present a management protocol, and to evaluate the results of treatment. DESIGN: Retrospective clinical study. SETTING: Level one trauma center at Harborview Medical Center. PATIENTS: During a sixty-eight-month period, 695 patients with pelvic ring disruptions were treated at a level one trauma center. Thirteen (1.9%) of these patients had a severely comminuted iliac fracture. All patients were men, ranging in age from twenty to eighty years (mean, 38 years). These patients were polytraumatized and had a mean Injury Severity Score of 23. Eleven of the thirteen patients had severe iliac and flank degloving injuries. Five patients had open fractures, one with fecal contamination requiring diverting colostomy. Six patients with clinical signs of hemodynamic instability had local arterial injuries associated with their fractures. All five patients with extension of the fracture into the greater sciatic notch were found to have a local arterial injury on angiography. One patient had a lumbosacral plexopathy on the fractured side. Four patients had traumatic brain injuries. INTERVENTION: All thirteen patients were treated operatively. Routine pelvic external fixation was not possible because of the iliac comminution. Stable internal fixation was accomplished by an anterior iliac surgical exposure using lag screw and plate combinations. The open wounds and degloving injuries were treated with irrigation, debridement, and closed suction drainage. MAIN OUTCOME MEASUREMENTS: Healing and stability of fixation were assessed clinically and on pelvic radiographs. RESULTS: Comminuted iliac fractures were divided into two patient groups, according to associated pelvic ring disruption. Follow-up evaluations were available for all patients at a mean of eighteen months after injury. There were no deaths. All of the fractures healed clinically and radiographically. In one patient, fecal contamination caused a polymicrobial wound infection, and this patient had an associated delay in union of the fracture. Another patient with an open fracture developed a deep wound infection. Both infections responded to local management and antibiotics. There were no complications associated with the degloving injuries. CONCLUSIONS: Comminuted iliac fractures occur in two distinct patterns and are associated with numerous local injuries that complicate management. Management protocols should include early open reduction and stable internal fixation. Traumatic open wounds should not be closed primarily. Primary closure with closed suction drainage is effective in the management of associated degloving injuries. Extension of the fracture into the greater sciatic notch warrants further evaluation with pelvic angiography.

Electrodeposited defect chemistry superlattices.

Nanometer-scale layered structures based on thallium(III) oxide were electrodeposited in a beaker at room temperature by pulsing the applied potential during deposition. The conducting metal oxide samples were superlattices, with layers as thin as 6.7 nanometers. The defect chemistry was a function of the applied overpotential: High overpotentials favored oxygen vacancies, whereas low overpotentials favored cation interstitials. The transition from one defect chemistry to another in this nonequilibrium process occurred in the same potential range (100 to 120 millivolts) in which the rate of the back electron transfer reaction became significant. The epitaxial structures have the high carrier density and low electronic dimensionality of high transition temperature superconductors.

Scanning tunneling microscopy of electrodeposited ceramic superlattices.

Cleaved cross sections of nanometer-scale ceramic superlattices fabricated from materials of the lead-thallium-oxygen system were imaged in the scanning tunneling microscope (STM). The apparent height differences between the layers were attributed to composition-dependent variations in local electrical properties. For a typical superlattice, the measured modulation wavelength was 10.6 nanometers by STM and 10.8 nanometers by x-ray diffraction. The apparent height profile for potentiostatically deposited superlattices was more square than that for galvanostatically deposited samples. These results suggest that the composition follows the applied potential more closely than it follows the applied current. The x-ray diffraction pattern of a superlattice produced under potential control had satellites out to the fourth order around the (420) Bragg reflection.

Electrodeposited ceramic superlattices.

Ceramic superlattices have been produced by electrodeposition with modulation wavelengths in the range from 5 to 10 nanometers. The TlaPbbOc/TldPbeOf superlattices were deposited from a single aqueous solution at room temperature, and the layer thicknesses were galvanostatically controlled. The films showed strong preferred orientation and distinct first-order satellites around the Bragg reflections in the x-ray diffraction pattem. The modulation wavelengths calculated from the satellite spacings were in agreement with those calculated from Faraday's law. Because the modulation wavelengths are of electron mean free path dimensions, this dass of degenerate semiconductor metal-oxide superlattices may exhibit thickness-dependent quantum optical, electronic, or optoelectronic effects.

Identification of 5-hydroxytryptamine1D binding sites in human brain membranes.

High-affinity, specific 3H-5-hydroxytryptamine (5-HT) binding was analyzed in membrane homogenates of human frontal cortex, caudate, and globus pallidus. 5-HT1A and 5-HT1C binding sites were pharmacologically blocked using 100 nM 8-hydroxy-N,N-dipropyl-2-aminotetralin (8-OH-DPAT) and 100 nM mesulergine, respectively. The majority of 5-HT1 sites remained in each of the three brain regions under these conditions. The pattern of nucleotide interactions with these binding sites (GppNHp = GTP = GDP greater than GMP = adenine nucleotides) suggests a possible linkage to a G protein. RU 24969 competition studies confirmed the absence of 5-HT1B binding sites in human cortex, caudate, and globus pallidus. Drug interactions with putative 5-HT1D binding sites in bovine caudate membranes correlated significantly with their affinities for human membrane recognition sites labeled by 3H-5-HT in the presence of 100 nM 8-OH-DPAT + 100 nM mesulergine. We conclude that the majority of 3H-5-HT labeled recognition sites in human cortex, caudate, and globus pallidus represent 5-HT1D binding sites.