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Syed I Hussain,1– 3 Lamar O Mair,4 Alexander J Willis,5 Georgia Papavasiliou,2 Bing Liu,6 Irving N Weinberg,4 Herbert H Engelhard1,3,7 1Department of Neurosurgery, The University of Illinois at Chicago, Chicago, IL, USA; 2Biomedical Engineering Department, Illinois Institute of Technology, Chicago, IL, USA; 3NanoMagnetic Therapeutics Corp., Wilmette, IL, USA; 4Weinberg Medical Physics, Inc., North Bethesda, MD, USA; 5Department of Medicine, The University of Illinois at Chicago, Chicago, IL, USA; 6IMRA America, Inc., Ann Arbor, MI, USA; 7Department of Bioengineering, The University of Illinois at Chicago, Chicago, IL, USACorrespondence: Herbert H Engelhard, Email hengelhard@sbcglobal.netBackground: Rotational manipulation of chains or clusters of magnetic nanoparticles (MNPs) offers a means for directed translation and payload delivery that should be explored for clinical use. Multiple MNP types are available, yet few studies have performed side-by-side comparisons to evaluate characteristics such as velocity, movement at a distance, and capacity for drug conveyance or dispersion.Purpose: Our goal was to design, build, and study an electric device allowing simultaneous, multichannel testing (e.g., racing) of MNPs in response to a rotating magnetic field. We would then select the “best” MNP and use it with optimized device settings, to transport an unbound therapeutic agent.Methods: A magnetomotive system was constructed, with a Helmholtz pair of coils on either side of a single perpendicular coil, on top of which was placed an acrylic tray having multiple parallel lanes. Five different MNPs were tested: graphene-coated cobalt MNPs (TurboBeads™), nickel nanorods, gold-iron alloy MNPs, gold-coated Fe3O4 MNPs, and uncoated Fe3O4 MNPs. Velocities were determined in response to varying magnetic field frequencies (5– 200 Hz) and heights (0– 18 cm). Velocities were normalized to account for minor lane differences. Doxorubicin was chosen as the therapeutic agent, assayed using a CLARIOstar Plus microplate reader.Results: The MMS generated a maximal MNP velocity of 0.9 cm/s. All MNPs encountered a “critical” frequency at 20– 30 Hz. Nickel nanorods had the optimal response based on tray height and were then shown to enable unbound doxorubicin dispersion along 10.5 cm in < 30 sec.Conclusion: A rotating magnetic field can be conveniently generated using a three-coil electromagnetic device, and used to induce rotational and translational movement of MNP aggregates over mesoscale distances. The responses of various MNPs can be compared side-by-side using multichannel acrylic trays to assess suitability for drug delivery, highlighting their potential for further in vivo applications.Keywords: electromagnetic field, doxorubicin, drug delivery, magnetic drug targeting, nanoparticle assay, rotating fields

A demonstration-scale outdoor constructed wetland (CW) wastewater treatment system was evaluated for about two years for its effectiveness in treating septic system effluents. The system included three treatment cells: an anaerobic cell, an aerated cell, and a basic oxygen furnace slag (BOFS)-based phosphorus (P) treatment cell. High removal efficiencies were achieved, with reductions of >99% for PO4-P, >83% for NH3-N, >99% for cBOD5, and >76% for COD, with influent concentrations averaging 6, 48, 63, and 143 mg L−1, respectively. Additionally, pathogens removal were high, with an over 99% decrease in E. coli and total coliform levels. The BOFS cell was critical, elevating effluent pH to 10.9 ± 1.5, which effectively inactivated pathogens. Environmental safety before discharge was ensured by CO2(g) sparging to adjust the pH and a zero-valent iron layer in the BOFS cell to control dissolved metal concentrations. Analytical techniques (FESEM-EDX, FTIR, and XANES) confirmed the formation of Ca carbonate and Ca phosphate on spent BOFS, highlighting their role in the treatment process. This study highlights the potential of integrating complementary technologies in constructed wetlands for sustainable and efficient wastewater management. [ABSTRACT FROM AUTHOR]

Background and purposeEndovascular strategies provide unique opportunity to correlate angiographic measures of collateral circulation at the time of endovascular therapy. We conducted systematic analyses of collaterals at conventional angiography on recanalization, reperfusion, and clinical outcomes in the endovascular treatment arm of the Interventional Management of Stroke (IMS) III trial.MethodsProspective evaluation of angiographic collaterals was conducted via central review of subjects treated with endovascular therapy in IMS III (n=331). Collateral grade before endovascular therapy was assessed with the American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology scale, blinded to all other data. Statistical analyses investigated the association between collaterals with baseline clinical variables, angiographic measures of recanalization, reperfusion and clinical outcomes.ResultsAdequate views of collateral circulation to the ischemic territory were available in 276 of 331 (83%) subjects. Collateral grade was strongly related to both recanalization of the occluded arterial segment (P=0.0016) and downstream reperfusion (P

To authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1552-6569.2008.00333.x Byline: Syed I. Hussain (1), John R. Lynch (1), Thomas Wolfe (1), Brian-Fred Fitzsimmons (1), Osama O. Zaidat (1) Keywords: Giant cerebral aneurysm; parent artery occlusion; Neuroform stent; aneurysm coiling; cerebral aneurysm Abstract: ABSTRACT BACKGROUND Endovascular treatment of giant cerebrovascular aneurysms (GCA) may be challenging due to risk of worsening mass effect, thromboembolism, rupture, and recurrence. The purpose of this study was to provide a preliminary evaluation of GCA therapy using stent-assisted coil parent artery occlusion (PAO) to reduce the likelihood of mass effect, aneurysm recurrence, and vessel recanalization. MATERIALS AND METHODS Five patients with GCAs were treated by PAO by deploying detachable coils within a Neuroform-3 stent across the aneurysm neck. Patients were monitored clinically to note any changes after treatment. Magnetic resonance angiography was performed 3 to 12 months after stent placement, and incomplete PAO and aneurysm recurrence were noted. RESULTS Stent-assisted PAO was technically successful in all GCAs with no residual aneurysm filling and without any coil herniation into the aneurysm sac. None of the patients had recanalization of the vessel or GCA or clinical worsening over a follow-up period of 3-17 months. Symptomatic mass effect improved in 2 and resolved in 2 patients. CONCLUSION Based on our preliminary experience, stent-assisted PAO in GCAs is technically feasible and may be a valid option in patients who tolerate balloon test occlusion to minimize the likelihood of increased mass effect from coil embolization. Author Affiliation: (1)From the Neurointerventional Section, Department of Neurology, Medical College of Wisconsin, Milwaukee, Wisconsin. Article History: Acceptance: Received February 16, 2008, and in revised form September 1, 2008, October 2, 2008. Accepted for publication October 2, 2008. Article note: Correspondence: Address correspondence to Osama O. Zaidat, MD, MS, Director, Neurointerventional Program, Medical College of Wisconsin, Department of Neurology, 9200 West Wisconsin Avenue, Milwaukee, WI 53226. E-mail: szaidat@mcw.edu