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1. Meta‐analysis of individual‐patient data from EVAR‐1, DREAM, OVER and ACE trials comparing outcomes of endovascular or open repair for abdominal aortic aneurysm over 5 years

Author

Powell, J. T., Sweeting, M. J., Ulug, P., Blankensteijn, J. D., Lederle, F. A., Becquemin, J.‐P., Greenhalgh, R. M., Greenhalgh, R. M., Beard, J. D., Buxton, M. J., Brown, L. C., Harris, P. L., Powell, J. T., Rose, J. D. G., Russell, I. T., Sculpher, M. J., Thompson, S. G., Lilford, R.J., Bell, P. R. F., Greenhalgh, R. M., Whitaker, S.C., Poole‐Wilson, the late P.A., Ruckley, C. V., Campbell, W. B., Dean, M. R. E., Ruttley, M. S. T., Coles, E. C., Powell, J. T., Halliday, A., Gibbs, S. J., Brown, L. C., Epstein, D., Sculpher, M. J., Thompson, S. G., Hannon, R. J., Johnston, L., Bradbury, A. W., Henderson, M. J., Parvin, S. D., Shepherd, D. F. C., Greenhalgh, R. M., Mitchell, A. W., Edwards, P. R., Abbott, G. T., Higman, D. J., Vohra, A., Ashley, S., Robottom, C., Wyatt, M. G., Rose, J. D. G., Byrne, D., Edwards, R., Leiberman, D. P., McCarter, D. H., Taylor, P. R., Reidy, J. F., Wilkinson, A. R., Ettles, D. F., Clason, A. E., Leen, G. L. S., Wilson, N. V., Downes, M., Walker, S. R., Lavelle, J. M., Gough, M. J., McPherson, S., Scott, D. J. A., Kessell, D. O., Naylor, R., Sayers, R., Fishwick, N. G., Harris, P. L., Gould, D. A., Walker, M. G., Chalmers, N. C., Garnham, A., Collins, M. A., Beard, J. D., Gaines, P. A., Ashour, M. Y., Uberoi, R., Braithwaite, B., Whitaker, S. C., Davies, J. N., Travis, S., Hamilton, G., Platts, A., Shandall, A., Sullivan, B. A., Sobeh, M., Matson, M., Fox, A. D., Orme, R., Yusef, W., Doyle, T., Horrocks, M., Hardman, J., Blair, P. H. B., Ellis, P. K., Morris, G., Odurny, A., Vohra, R., Duddy, M., Thompson, M., Loosemore, T. M. L., Belli, A. M., Morgan, R., Adiseshiah, M., Brookes, J. A. S., McCollum, C. N., Ashleigh, R., Aukett, M., Baker, S., Barbe, E., Batson, N., Bell, J., Blundell, J., Boardley, D., Boyes, S., Brown, O., Bryce, J., Carmichael, M., Chance, T., Coleman, J., Cosgrove, C., Curran, G., Dennison, T., Devine, C., Dewhirst, N., Errington, B., Farrell, H., Fisher, C., Fulford, P., Gough, M., Graham, C., Hooper, R., Horne, G., Horrocks, L., Hughes, B., Hutchings, T., Ireland, M., Judge, C., Kelly, L., Kemp, J., Kite, A., Kivela, M., Lapworth, M., Lee, C., Linekar, L., Mahmood, A., March, L., Martin, J., Matharu, N., McGuigen, K., Morris‐Vincent, P., Murray, S., Murtagh, A., Owen, G., Ramoutar, V., Rippin, C., Rowley, J., Sinclair, J., Spencer, S., Taylor, V., Tomlinson, C., Ward, S., Wealleans, V., West, J., White, K., Williams, J., Wilson, L., Grobbee, D. E., Blankensteijn, J. D., Bak, A. A. A., Buth, J., Pattynama, P. M., Verhoeven, E. L. G., van Voorthuisen, A. E., Blankensteijn, J. D., Balm, R., Buth, J., Cuypers, P. W. M., Grobbee, D. E., Prinssen, M., van Sambeek, M. R. H. M., Verhoeven, E. L. G., Baas, A. F., Hunink, M. G., van Engelshoven, J. M., Jacobs, M. J. H. M., de Mol, B. A. J. M., van Bockel, J. H., Balm, R., Reekers, J., Tielbeek, X., Verhoeven, E. L. G., Wisselink, W., Boekema, N., Heuveling, L. M., Sikking, I., Prinssen, M., Balm, R., Blankensteijn, J. D., Buth, J., Cuypers, P. W. M., van Sambeek, M. R. H. M., Verhoeven, E. L. G., de Bruin, J. L., Baas, A. F., Blankensteijn, J. D., Prinssen, M., Buth, J., Tielbeek, A.V., Blankensteijn, J. D., Balm, R., Reekers, J. A., van Sambeek, M. R. H. M., Pattynama, P., Verhoeven, E. L. G., Prins, T., van der Ham, A. C., van der Velden, J. J. I. M., van Sterkenburg, S. M. M., ten Haken, G. B., Bruijninckx, C. M. A., van Overhagen, H., Tutein Nolthenius, R. P., Hendriksz, T. R., Teijink, J. A. W., Odink, H. F., de Smet, A. A. E. A., Vroegindeweij, D., van Loenhout, R. M. M., Rutten, M. J., Hamming, J. F., Lampmann, L. E. H., Bender, M. H. M., Pasmans, H., Vahl, A. C., de Vries, C., Mackaay, A. J. C., van Dortmont, L. M. C., van der Vliet, A. J., Schultze Kool, L. J., Boomsma, J. H. B., van Dop, H. R., de Mol van Otterloo, J. C. A., de Rooij, T. P. W., Smits, T. M., Yilmaz, E. N., Wisselink, W., van den Berg, F. G., Visser, M. J. T., van der Linden, E., Schurink, G. W. H., de Haan, M., Smeets, H. J., Stabel, P., van Elst, F., Poniewierski, J., Vermassen, F. E. G., Lederle, F. A., Freischlag, J. A., Kohler, T. R., Latts, E., Matsumura, J., Padberg, F. T., Jr, Kyriakides, T. C., Swanson, K. M., Guarino, P., Peduzzi, P., Antonelli, M., Cushing, C., Davis, E., Durant, L., Joyner, S., Kossack, the late A., Kyriakides, T. C., LeGwin, Mary, McBride, V., OʼConnor, T., Poulton, J., Stratton, the late S., Zellner, S., Snodgrass, A. J., Thornton, J., Swanson, K. M., Haakenson, C. M., Stroupe, K.T., Jonk, Y., Hallett, J. W., Hertzer, N., Towne, J., Katz, D. A., Karrison, T., Matts, J. P., Marottoli, R., Kasl, S., Mehta, R., Feldman, R., Farrell, W., Allore, H., Perry, E., Niederman, J., Randall, F., Zeman, M., Beckwith, the late D., OʼLeary, T. J., Huang, G. D., Latts, E., Bader, M., Ketteler, E. R., Kingsley, D. D., Marek, J. M., Massen, R. J., Matteson, B. D., Pitcher, J. D., Langsfeld, M., Corson, J. D., Goff, J. M., Jr, Kasirajan, K., Paap, C., Robertson, D. C., Salam, A., Veeraswamy, R., Milner, R., Kasirajan, K., Guidot, J., Lal, B. K., Busuttil, S. J., Lilly, M. P., Braganza, M., Ellis, K., Patterson, M. A., Jordan, W. D., Whitley, D., Taylor, S., Passman, M., Kerns, D., Inman, C., Poirier, J., Ebaugh, J., Raffetto, J., Chew, D., Lathi, S., Owens, C., Hickson, K., Dosluoglu, H. H., Eschberger, K., Kibbe, M. R., Baraniewski, H. M., Matsumura, J., Endo, M., Busman, A., Meadows, W., Evans, M., Giglia, J. S., El Sayed, H., Reed, A. B., Ruf, M., Ross, S., Jean‐Claude, J. M., Pinault, G., Kang, P., White, N., Eiseman, M., Jones, the late R., Timaran, C. H., Modrall, J. G., Welborn, M. B., III, Lopez, J., Nguyen, T., Chacko, J. K. Y., Granke, K., Vouyouka, A. G., Olgren, E., Chand, P., Allende, B., Ranella, M., Yales, C., Whitehill, T. A., Krupski, the late W. C., Nehler, M. R., Johnson, S. P., Jones, D. N., Strecker, P., Bhola, M. A., Shortell, C. K., Gray, J. L., Lawson, J. H., McCann, R., Sebastian, M.W., Kistler Tetterton, J., Blackwell, C., Prinzo, P. A., Lee, N., Padberg, F. T., Jr, Cerveira, J. J., Lal, B. K., Zickler, R. W., Hauck, K. A., Berceli, S. A., Lee, W. A., Ozaki, C. K., Nelson, P. R., Irwin, A. S., Baum, R., Aulivola, B., Rodriguez, H., Littooy, F. N., Greisler, H., OʼSullivan, M. T., Kougias, P., Lin, P. H., Bush, R. L., Guinn, G., Bechara, C., Cagiannos, C., Pisimisis, G., Barshes, N., Pillack, S., Guillory, B., Cikrit, D., Lalka, S. G., Lemmon, G., Nachreiner, R., Rusomaroff, M., OʼBrien, E., Cullen, J. J., Hoballah, J., Sharp, W. J., McCandless, J. L., Beach, V., Minion, D., Schwarcz, T. H., Kimbrough, J., Ashe, L., Rockich, A., Warner‐Carpenter, J., Moursi, M., Eidt, J. F., Brock, S., Bianchi, C., Bishop, V., Gordon, I. L., Fujitani, R., Kubaska, S. M., III, Behdad, M., Azadegan, R., Ma Agas, C., Zalecki, K., Hoch, J. R., Carr, S. C., Acher, C., Schwarze, M., Tefera, G., Mell, M., Dunlap, B., Rieder, J., Stuart, J. M., Weiman, D. S., Abul‐Khoudoud, O., Garrett, H. E., Walsh, S. M., Wilson, K. L., Seabrook, G. R., Cambria, R. A., Brown, K. R., Lewis, B. D., Framberg, S., Kallio, C., Barke, R. A., Santilli, S. M., dʼAudiffret, A. C., Oberle, N., Proebstle, C., Johnson, L. L., Jacobowitz, G. R., Cayne, N., Rockman, C., Adelman, M., Gagne, P., Nalbandian, M., Caropolo, L. J., Pipinos, I. I., Johanning, J., Lynch, T., DeSpiegelaere, H., Purviance, G., Zhou, W., Dalman, R., Lee, J. T., Safadi, B., Coogan, S. M., Wren, S. M., Bahmani, D. D., Maples, D., Thunen, S., Golden, M. A., Mitchell, M. E., Fairman, R., Reinhardt, S., Wilson, M. A., Tzeng, E., Muluk, S., Peterson, N. M., Foster, M., Edwards, J., Moneta, G. L., Landry, G., Taylor, L., Yeager, R., Cannady, E., Treiman, G., Hatton‐Ward, S., Salabsky, the late B., Kansal, N., Owens, E., Estes, M., Forbes, B. A., Sobotta, C., Rapp, J. H., Reilly, L. M., Perez, S. L., Yan, K., Sarkar, R., Dwyer, S. S., Perez, S., Chong, K., Kohler, T. R., Hatsukami, T. S., Glickerman, D. G., Sobel, M., Burdick, T. S., Pedersen, K., Cleary, P., Back, M., Bandyk, D., Johnson, B., Shames, M., Reinhard, R. L., Thomas, S. C., Hunter, G. C., Leon, L. R., Jr, Westerband, A., Guerra, R. J., Riveros, M., Mills, J. L., Sr, Hughes, J. D., Escalante, A. M., Psalms, S. B., Day, N. N., Macsata, R., Sidawy, A., Weiswasser, J., Arora, S., Jasper, B. J., Dardik, A., Gahtan, V., Muhs, B. E., Sumpio, B. E., Gusberg, R. J., Spector, M., Pollak, J., Aruny, J., Kelly, E. L., Wong, J., Vasilas, P., Joncas, C., Gelabert, H. A., DeVirgillio, C., Rigberg, D. A., Cole, L., Becquemin, J.‐P., Marzelle, J., Becquemin, J.‐P., Sapoval, M., Becquemin, J.‐P., Favre, J.‐P., Watelet, J., Lermusiaux, P., Sapoval, M., Lepage, E., Hemery, F., Dolbeau, G., Hawajry, N., Cunin, P., Harris, P., Stockx, L., Chatellier, G., Mialhe, C., Fiessinger, J.‐N., Pagny, L., Kobeiter, H., Boissier, C., Lacroix, P., Ledru, F., Pinot, J.‐J., Deux, J.‐F., Tzvetkov, B., Duvaldestin, P., Watelet, J., Jourdain, C., David, V., Enouf, D., Ady, N., Krimi, A., Boudjema, N., Jousset, Y., Enon, B., Blin, V., Picquet, J., LʼHoste, P., Thouveny, F., Borie, H., Kowarski, S., Pernes, J.‐M., Auguste, M., Becquemin, J.‐P., Desgranges, P., Allaire, E., Marzelle, J., Kobeiter, H., Meaulle, P.‐Y., Chaix, D., Juliae, P., Fabiani, J. N., Chevalier, P., Combes, M., Seguin, A., Belhomme, D., Sapoval, M., Baque, J., Pellerin, O., Favre, J. P., Barral, X., Veyret, C., Watelet, J., Peillon, C., Plissonier, D., Thomas, P., Clavier, E., Lermusiaux, P., Martinez, R., Bleuet, F., C, Dupreix, Verhoye, J. P., Langanay, T., Heautot, J. F., Koussa, M., Haulon, S., Halna, P., Destrieux, L., Lions, C., Wiloteaux, S., Beregi, J. P., Bergeron, P., Pinot, J.‐J., Patra, P., Costargent, A., Chaillou, P., DʼAlicourt, A., Goueffic, Y., Cheysson, E., Parrot, A., Garance, P., Demon, A., Tyazi, A., Pillet, J.‐C., Lescalie, F., Tilly, G., Steinmetz, E., Favier, C., Brenot, R., Krause, D., Cercueil, J. P., Vahdat, O., Sauer, M., Soula, P., Querian, A., Garcia, O., Levade, M., Colombier, D., Cardon, J.‐M., Joyeux, A., Borrelly, P., Dogas, G., Magnan, P.‐É., Branchereau, A., Bartoli, J.‐M., Hassen‐Khodja, R., Batt, M., Planchard, P.‐F., Bouillanne, P.‐J., Haudebourg, P., Bayne, J., Gouny, P., Badra, A., Braesco, J., Nonent, M., Lucas, A., Cardon, A., Kerdiles, Y., Rolland, Y., Kassab, M., Brillu, C., Goubault, F., Tailboux, L., Darrieux, H., Briand, O., Maillard, J.‐C., Varty, K., and Cousins, C.

Published
2017
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13. Radiative property degradation of water impinging on thermally-controlled surfaces under space conditions.

Author

Maples, D, Spiller, M. H, and Maples, G

Subjects
Physics, General
Abstract

Review of the results of an investigation aimed at determining experimentally the directional monochromatic reflectance changes caused under high-vacuum space conditions by a water spray impinging on thermally controlled surfaces consisting of three paint specimens (Z93, S13G, and 92-007) and an aluminum foil. The first two paints and the aluminum foil suffered considerable physical damage, but only small changes resulted in the reflectance of the paints while the reflectance of the aluminum foil decreased with increase in exposure time to the water jet. Only the 92-007 Dow Corning paint retained the same physical and reflective characteristics.

Published
1973

14. Design and construction of a remote sensing apparatus

Author

Maples, D and Hagewood, J. F

Subjects
Instrumentation And Photography
Abstract

The methods of identifying plant and soil types using remote sensing techniques are described. The equipment employed consists of a balloon system and a mobile remote sensing laboratory housing a radiometer which is mounted on a turret mechanism. The radiometer is made up of a telescope whose lenses are replaced by mirrors which channel received radiation into a monochromator. The radiation is then focused onto detectors for measurement of the intensity of the electromagnetic energy as a function of wavelength. Measurements from a wavelength of 0.2 microns to 15 microns are obtained with the system. diagrams are provided.

Published
1973

26. Elastin-like polypeptide incorporated thermally sensitive liposome improve antibiotic therapy against musculoskeletal bacterial pathogens.

Author

Nigatu AS, Ashar H, Sethuraman SN, Wardlow R, Maples D, Malayer J, and Ranjan A

Subjects
Anti-Bacterial Agents pharmacology, Humans, Anti-Bacterial Agents therapeutic use, Bacteria pathogenicity, Elastin metabolism, Liposomes metabolism, Peptides metabolism
Abstract

Musculoskeletal infections caused by bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa in children and adults can lead to adverse outcomes including a need for extensive surgical debridement and limb amputation. To enable targeted antimicrobial release in infected tissues, the objective of this study was to design and investigate novel elastin-like polypeptide (ELP)-based thermally sensitive liposomes in vitro. ELP biopolymers can change their phase behaviour at higher temperatures. We hypothesised that ELP-TSL will improve therapeutic efficacy by releasing antimicrobial payloads locally at higher temperatures (≥39 °C). ELP-TSL library were formulated by varying cholesterol and phospholipid composition by the thin film and extrusion method. A broad-spectrum antimicrobial (Ciprofloxacin or Cipro) was encapsulated inside the liposomes by the ammonium sulphate gradient method. Cipro release from ELP-TSLs was assessed in physiological buffers containing ∼25% serum by fluorescence spectroscopy, and efficacy against Staphylococcus aureus and Pseudomonas aeruginosa was assessed by disc diffusion and planktonic assay. Active loading of Cipro achieved an encapsulation efficiency of 40-70% in the ELP-TSL depending upon composition. ELP-TSL Cipro release was near complete at ≥39 °C; however, the release rates could be delayed by cholesterol. Triggered release of Cipro from ELP-TSL at ∼42 °C induced significant killing of S. aureus and P. aeruginosa compared to 37 °C. Our in vitro data suggest that ELP-TSL may potentially improve bacterial wound therapy in patients.

Published
2018
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27. Temperature-sensitive liposomal ciprofloxacin for the treatment of biofilm on infected metal implants using alternating magnetic fields.

Author

Munaweera I, Shaikh S, Maples D, Nigatu AS, Sethuraman SN, Ranjan A, Greenberg DE, and Chopra R

Subjects
Anti-Bacterial Agents pharmacology, Biofilms, Ciprofloxacin pharmacology, Humans, Magnetic Fields, Microscopy, Electron, Scanning, Anti-Bacterial Agents therapeutic use, Ciprofloxacin therapeutic use, Liposomes metabolism
Abstract

Implants are commonly used as a replacement for damaged tissue. Many implants, such as pacemakers, chronic electrode implants, bone screws, and prosthetic joints, are made of or contain metal. Infections are one of the difficult to treat complications associated with metal implants due to the formation of biofilm, a thick aggregate of extracellular polymeric substances (EPS) produced by the bacteria. In this study, we treated a metal prosthesis infection model using a combination of ciprofloxacin-loaded temperature-sensitive liposomes (TSL) and alternating magnetic fields (AMF). AMF heating is used to disrupt the biofilm and release the ciprofloxacin-loaded TSL. The three main objectives of this study were to (1) investigate low- and high-temperature-sensitive liposomes (LTSLs and HTSLs) containing the antimicrobial agent ciprofloxacin for temperature-mediated antibiotic release, (2) characterise in vitro ciprofloxacin release and stability and (3) study the efficacy of combining liposomal ciprofloxacin with AMF against Pseudomonas aeruginosa biofilms grown on metal washers. The release of ciprofloxacin from LTSL and HTSL was assessed in physiological buffers. Results demonstrated a lower transition temperature for both LTSL and HTSL formulations when incubated in serum as compared with PBS, with a more pronounced impact on the HTSLs. Upon combining AMF with temperature-sensitive liposomal ciprofloxacin, a 3 log reduction in CFU of Pseudomonas aeruginosa in biofilm was observed. Our initial studies suggest that AMF exposure on metal implants can trigger release of antibiotic from temperature sensitive liposomes for a potent bactericidal effect on biofilm.

Published
2018
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28. Sequential HIFU heating and nanobubble encapsulation provide efficient drug penetration from stealth and temperature sensitive liposomes in colon cancer.

Author

VanOsdol J, Ektate K, Ramasamy S, Maples D, Collins W, Malayer J, and Ranjan A

Subjects
Animals, Antibiotics, Antineoplastic pharmacokinetics, Antibiotics, Antineoplastic therapeutic use, Cell Line, Tumor, Colon drug effects, Colon pathology, Colonic Neoplasms pathology, Doxorubicin pharmacokinetics, Doxorubicin therapeutic use, Drug Liberation, Fluorocarbons chemistry, Humans, Hyperthermia, Induced methods, Mice, Nude, Microbubbles, Temperature, Tumor Burden drug effects, Antibiotics, Antineoplastic administration & dosage, Colonic Neoplasms drug therapy, Contrast Media chemistry, Delayed-Action Preparations chemistry, Doxorubicin administration & dosage, Drug Delivery Systems methods, Liposomes chemistry
Abstract

Mild hyperthermia generated using high intensity focused ultrasound (HIFU) and microbubbles (MBs) can improve tumor drug delivery from non-thermosensitive liposomes (NTSLs) and low temperature sensitive liposomes (LTSLs). However, MB and HIFU are limited by the half-life of the contrast agent and challenges in accurate control of large volume tumor hyperthermia for longer duration (>30min.). The objectives of this study were to: 1) synthesize and characterized long-circulating echogenic nanobubble encapsulated LTSLs (ELTSLs) and NTSLs (ENTSLs), 2) evaluate in vivo drug release following short duration (~20min each) HIFU treatments administered sequentially over an hour in a large volume of mouse xenograft colon tumor, and 3) determine the impact of the HIFU/nanobubble combination on intratumoral drug distribution. LTSLs and NTSLs containing doxorubicin (Dox) were co-loaded with a nanobubble contrast agent (perfluoropentane, PFP) using a one-step sonoporation method to create ELTSLs and ENTSLs, which then were characterized for size, release in a physiological buffer, and ability to encapsulate PFP. For the HIFU group, mild hyperthermia (40-42°C) was completed within 90min after liposome infusion administered sequentially in three regions of the tumor. Fluorescence microscopy and high performance liquid chromatography analysis were performed to determine the spatial distribution and concentration of Dox in the treated regions. PFP encapsulation within ELTSLs and ENTSLs did not impact size or caused premature drug release in physiological buffer. As time progressed, the delivery of Dox decreased in HIFU-treated tumors with ELTSLs, but this phenomenon was absent in the LTSL, NTSL, and ENTSL groups. Most importantly, PFP encapsulation improved Dox penetration in the tumor periphery and core and did not impact the distribution of Dox in non-tumor organs/tissues. Data from this study suggest that short duration and sequential HIFU treatment could have significant benefits and that its action can be potentiated by nanobubble agents to result in improved drug penetration., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Published
2017
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29. Motion Compensated Ultrasound Imaging Allows Thermometry and Image Guided Drug Delivery Monitoring from Echogenic Liposomes.

Author

Ektate K, Kapoor A, Maples D, Tuysuzoglu A, VanOsdol J, Ramasami S, and Ranjan A

Subjects
Animals, Disease Models, Animal, Drug Carriers metabolism, Mice, Theranostic Nanomedicine methods, Antibiotics, Antineoplastic pharmacokinetics, Colonic Neoplasms diagnosis, Colonic Neoplasms drug therapy, Contrast Media pharmacokinetics, Doxorubicin pharmacokinetics, Liposomes metabolism, Thermometry, Ultrasonography
Abstract

Ultrasound imaging is widely used both for cancer diagnosis and to assess therapeutic success, but due to its weak tissue contrast and the short half-life of commercially available contrast agents, it is currently not practical for assessing motion compensated contrast-enhanced tumor imaging, or for determining time-resolved absolute tumor temperature while simultaneously reporting on drug delivery. The objectives of this study were to: 1) develop echogenic heat sensitive liposomes (E-LTSL) and non-thermosensitive liposomes (E-NTSL) to enhance half-life of contrast agents, and 2) measure motion compensated temperature induced state changes in acoustic impedance and Laplace pressure of liposomes to monitor temperature and doxorubicin (Dox) delivery to tumors. LTSL and NTSL containing Dox were co-loaded with an US contrast agent (perfluoropentane, PFP) using a one-step sonoporation method to create E-LTSL and E-NTSL. To determine temperature induced intensity variation with respect to the state change of E-LTSL and E-NTSL in mouse colon tumors, cine acquisition of 20 frames/second for about 20 min (or until wash out) at temperatures of 42°C, 39.5°C, and 37°C was performed. A rigid rotation and translation was applied to each of the "key frames" to adjust for any gross motion that arose due to motion of the animal or the transducer. To evaluate the correlation between ultrasound (US) intensity variation and Dox release at various temperatures, treatment (5 mg Dox/kg) was administered via a tail vein once tumors reached a size of 300-400 mm(3), and mean intensity within regions of interest (ROIs) defined for each sample was computed over the collected frames and normalized in the range of [0,1]. When the motion compensation technique was applied, a > 2-fold drop in standard deviation in mean image intensity of tumor was observed, enabling a more robust estimation of temporal variations in tumor temperatures for 15-20 min. due to state change of E-LTSL and E-NTSL. Consequently, a marked increase in peak intensity at 42°C compared to 37°C that corresponded with enhanced Dox delivery from E-LTSL in tumors was obtained. Our results suggest that echogenic liposomes provide a predictable change in tumor vascular contrast with temperature, and this property could be applicable to nanomonitoring of drug delivery in real time., Competing Interests: The authors have declared that no competing interest exists.

Published
2016
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30. Targeted antibiotic delivery using low temperature-sensitive liposomes and magnetic resonance-guided high-intensity focused ultrasound hyperthermia.

Author

Wardlow R, Bing C, VanOsdol J, Maples D, Ladouceur-Wodzak M, Harbeson M, Nofiele J, Staruch R, Ramachandran A, Malayer J, Chopra R, and Ranjan A

Subjects
Animals, Anti-Bacterial Agents chemistry, Anti-Bacterial Agents pharmacokinetics, Biofilms drug effects, Biofilms growth & development, Ciprofloxacin chemistry, Ciprofloxacin pharmacokinetics, Drug Liberation, Liposomes, Magnetic Resonance Imaging, Male, Microscopy, Electron, Scanning, Muscle, Skeletal diagnostic imaging, Muscle, Skeletal metabolism, Rats, Sprague-Dawley, Skin metabolism, Staphylococcus aureus growth & development, Staphylococcus aureus ultrastructure, Temperature, Anti-Bacterial Agents administration & dosage, Ciprofloxacin administration & dosage, High-Intensity Focused Ultrasound Ablation methods, Staphylococcus aureus drug effects
Abstract

Chronic non-healing wound infections require long duration antibiotic therapy, and are associated with significant morbidity and health-care costs. Novel approaches for efficient, readily-translatable targeted and localised antimicrobial delivery are needed. The objectives of this study were to 1) develop low temperature-sensitive liposomes (LTSLs) containing an antimicrobial agent (ciprofloxacin) for induced release at mild hyperthermia (∼42 °C), 2) characterise in vitro ciprofloxacin release, and efficacy against Staphylococcus aureus plankton and biofilms, and 3) determine the feasibility of localised ciprofloxacin delivery in combination with MR-HIFU hyperthermia in a rat model. LTSLs were loaded actively with ciprofloxacin and their efficacy was determined using a disc diffusion method, MBEC biofilm device, and scanning electron microscopy (SEM). Ciprofloxacin release from LTSLs was assessed in a physiological buffer by fluorescence spectroscopy, and in vivo in a rat model using MR-HIFU. Results indicated that < 5% ciprofloxacin was released from the LTSL at body temperature (37 °C), while >95% was released at 42 °C. Precise hyperthermia exposures in the thigh of rats using MR-HIFU during intravenous (i.v.) administration of the LTSLs resulted in a four fold greater local concentration of ciprofloxacin compared to controls (free ciprofloxacin + MR-HIFU or LTSL alone). The biodistribution of ciprofloxacin in unheated tissues was fairly similar between treatment groups. Triggered release at 42 °C from LTSL achieved significantly greater S. aureus killing and induced membrane deformation and changes in biofilm matrix compared to free ciprofloxacin or LTSL at 37 °C. This technique has potential as a method to deliver high concentration antimicrobials to chronic wounds.

Published
2016
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31. Synthesis and characterisation of ultrasound imageable heat-sensitive liposomes for HIFU therapy.

Author

Maples D, McLean K, Sahoo K, Newhardt R, Venkatesan P, Wood B, and Ranjan A

Subjects
Animals, Antibiotics, Antineoplastic pharmacokinetics, Antibiotics, Antineoplastic therapeutic use, Cell Line, Tumor, Contrast Media pharmacokinetics, Doxorubicin pharmacokinetics, Doxorubicin therapeutic use, Fluorocarbons pharmacokinetics, Hot Temperature, Humans, Liposomes, Male, Mice, Inbred BALB C, Mice, Nude, Neoplasms drug therapy, Neoplasms metabolism, Antibiotics, Antineoplastic administration & dosage, Contrast Media administration & dosage, Doxorubicin administration & dosage, Fluorocarbons administration & dosage, High-Intensity Focused Ultrasound Ablation, Neoplasms therapy
Abstract

Background/objective: Novel approaches allowing efficient, readily translatable image-guided drug delivery (IGDD) against solid tumours is needed. The objectives of this study were to: 1) develop echogenic low temperature sensitive liposomes (E-LTSLs) loaded with an ultrasound (US) contrast agent (perfluoropentane, PFP), 2) determine the in vitro and in vivo stability of contrast agent encapsulation, 3) co-encapsulate and characterise doxorubicin (Dox) E-LTSL, and cellular uptake and cytotoxicity in combination with high intensity focused ultrasound (HIFU)., Method: E-LTSLs were loaded passively with PFP and actively with Dox. PFP encapsulation in E-LTSL was determined by transmission electron microscopy (TEM), and US imageability was determined in tissue-mimicking phantoms and mouse tumour model. Dox release from E-LTSL in physiological buffer was quantified by fluorescence spectroscopy. Cellular uptake and cytotoxicity of E-LTSL in the presence of HIFU-induced mild hyperthermia (∼40-42 °C) was determined in a 3D tumour spheroid model., Results: TEM and US confirmed that the PFP emulsion was contained within LTSLs. Phantom and animal studies showed that the E-LTSLs were echogenic. Temperature versus size increase and Dox release kinetics of E-LTSLs demonstrated no difference compared to LTSL alone. Dox release was <5% within 1 h at baseline (25 °C) and body (37 °C) temperatures, and was >99% under hyperthermia. E-LTSL plus HIFU achieved significantly greater Dox uptake in spheroids and cytotoxicity compared to body temperature., Conclusion: A stable US-imageable liposome co-loaded with Dox and PFP for in vivo IGDD was developed. Data suggest that HIFU can induce cellular uptake and toxicity with E-LTSLs.

Published
2015
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32. MRI-guided monitoring of thermal dose and targeted drug delivery for cancer therapy.

Author

Fernando R, Downs J, Maples D, and Ranjan A

Subjects
Animals, Antineoplastic Agents therapeutic use, Humans, Neoplasms pathology, Antineoplastic Agents administration & dosage, Drug Delivery Systems methods, Hyperthermia, Induced methods, Magnetic Resonance Imaging methods, Neoplasms therapy
Abstract

Application of localized hyperthermia treatment for solid tumor therapy is under active clinical investigation. The success of this treatment methodology, whether for tumor ablation or drug delivery, requires accurate target localization and real-time temperature mapping of the targeted region. Magnetic Resonance Imaging (MRI) can monitor temperature elevations in tissues in real-time during tumor therapy. MRI can also be applied in concert with methods such as High Intensity Focused Ultrasound (HIFU) to enable image-guided drug delivery (IGDD) from temperature sensitive nanocarriers, by exploiting not only its anatomic resolution, but its ability to detect and measure drug release using markers co-loaded with drugs within the nanocarriers. We review this rapidly emerging technology, providing an overview of MRI-guided tissue thermal dose monitoring for HIFU and Laser therapy, its role in targeted drug delivery and its future potential for clinical translation.

Published
2013
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33. Tumor Spheroids as an in vitro model for determining the therapeutic response to proton beam radiotherapy and thermally sensitive nanocarriers.

Author

Senavirathna LK, Fernando R, Maples D, Zheng Y, Polf JC, and Ranjan A

Subjects
Antineoplastic Agents pharmacology, Cell Culture Techniques methods, Cell Survival drug effects, Cell Survival radiation effects, Doxorubicin pharmacology, Drug Carriers radiation effects, Liposomes radiation effects, Models, Biological, Drug Therapy methods, Neoplasms drug therapy, Neoplasms radiotherapy, Proton Therapy methods
Abstract

Multicellular Tumor Spheroids (MCTS) strongly resemble tumor tissues, which makes them useful tools for radiation biology studies and screening of various chemotherapeutics. The goal of this pilot study was to use MCTS as an in vitro model to determine the response of cells to low temperature-sensitive liposomes (LTSLs) encapsulating doxorubicin (Dox) and proton beam radiotherapy (PBRT). Prior to treatment, MCTS were characterized for morphology and LTSLs were characterized for size, encapsulation efficiency, and ability to thermally release Dox (a model anticancer agent). Two groups of MCTS were treated with LTSL in combination with mild hyperthermia (40-42 °C) or PBRT alone in the presence of appropriate controls. Cytotoxic response was assessed after 48-72 h using an acid phosphatase assay. At 72 h, LTSL in combination with heat significantly reduced the viability of MCTS (15-30%) compared to the control (P < 0.05). A similar cytotoxic response was observed with PBRT treatment. The data suggest that like a monolayer cell culture, MCTS can be used to determine cytotoxic outcomes of thermal and proton therapy.

Published
2013
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34. Bateman bipolar hip arthroplasty. A review of 44 cases.

Author

Mannarino F, Maples D, Colwill JC, and Swanson AB

Subjects
Aged, Humans, Middle Aged, Postoperative Complications, Retrospective Studies, Hip Prosthesis
Abstract

A consecutive series of 71 Bateman hemiarthroplasties were performed in a single hospital over a 20-month period. Forty-four hips or 62% were available for review with an average follow up of 22 months. Of the 44 cases, the Bateman Universal Proximal Femur, original design was used in 40 acute, displaced femoral neck fractures, two failed Austin Moore prostheses, and two cases of femoral head osteonecrosis unassociated with fracture. The mean Harris hip score was 84.7%. Of the patients 93.2% had minimal or no pain. The range of motion was excellent and the dislocation rate was 1.8%. Morbidity was not increased compared to more conventional unipolar implant procedures. The Bateman Universal Proximal Femur (UPF) is felt to offer improved surgical results compared to Austin Moore and Thompson prostheses, and this may be due to the low friction inner bearing motion that occurs with this bipolar implant.

Published
1986
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