Preclinical evaluation of bioabsorbable polyglycolic acid spacer for particle therapy.

International journal of radiation oncology, biology, physics (2014-12-30)
Hiroaki Akasaka, Ryohei Sasaki, Daisuke Miyawaki, Naritoshi Mukumoto, Nor Shazrina Binti Sulaiman, Masaaki Nagata, Shigeru Yamada, Masao Murakami, Yusuke Demizu, Takumi Fukumoto
RESUMEN

To evaluate the efficacy and safety of a polyglycolic acid (PGA) spacer through physical and animal experiments. The spacer was produced with surgical suture material made of PGA, forming a 3-dimensional nonwoven fabric. For evaluation or physical experiments, 150-MeV proton or 320-MeV carbon-ion beams were used to generate 60-mm width of spread-out Bragg peak. For animal experiments, the abdomens of C57BL/6 mice, with or without the inserted PGA spacers, were irradiated with 20 Gy of carbon-ion beam (290 MeV) using the spread-out Bragg peak. Body weight changes over time were scored, and radiation damage to the intestine was investigated using hematoxylin and eosin stain. Blood samples were also evaluated 24 days after the irradiation. Long-term thickness retention and safety were evaluated using crab-eating macaques. No chemical or structural changes after 100 Gy of proton or carbon-ion irradiation were observed in the PGA spacer. Water equivalency of the PGA spacer was equal to the water thickness under wet condition. During 24 days' observation after 20 Gy of carbon-ion irradiation, the body weights of mice with the PGA spacer were relatively unchanged, whereas significant weight loss was observed in those mice without the PGA spacer (P<.05). In mice with the PGA spacer, villus and crypt structure were preserved after irradiation. No inflammatory reactions or liver or renal dysfunctions due to placement of the PGA spacer were observed. In the abdomen of crab-eating macaques, thickness of the PGA spacer was maintained 8 weeks after placement. The absorbable PGA spacer had water-equivalent, bio-compatible, and thickness-retaining properties. Although further evaluation is warranted in a clinical setting, the PGA spacer may be effective to stop proton or carbon-ion beams and to separate normal tissues from the radiation field.

MATERIALES
Referencia del producto
Marca
Descripción del producto

Sigma-Aldrich
Activated charcoal, DARCO®, −100 mesh particle size, powder
Supelco
Activated charcoal, powder
Sigma-Aldrich
Activated charcoal, powder, -100 particle size (mesh), decolorizing
Sigma-Aldrich
Activated charcoal, suitable for cell culture, suitable for plant cell culture
Sigma-Aldrich
Activated charcoal, DARCO®, 20-40 mesh particle size, granular
Supelco
Activated charcoal, puriss. p.a., powder
Sigma-Aldrich
Carbon, glassy, spherical powder, 2-12 μm, 99.95% trace metals basis
Sigma-Aldrich
Carbon, nanopowder, <100 nm particle size (TEM)
Sigma-Aldrich
Activated charcoal, untreated, granular, ≤5 mm
Sigma-Aldrich
Activated charcoal, DARCO®, 4-12 mesh particle size, granular
Sigma-Aldrich
Polyglycolic acid
Sigma-Aldrich
Activated Charcoal Norit®, Norit® CA1, wood, chemically activated, powder
Sigma-Aldrich
Activated charcoal, untreated, granular, 8-20 mesh
Sigma-Aldrich
Activated charcoal, acid-washed with hydrochloric acid
Sigma-Aldrich
Activated charcoal, DARCO®, 12-20 mesh, granular
Sigma-Aldrich
Activated Charcoal Norit®, Norit® GAC 1240W, from coal, for potable water processing, steam activated, granular
Sigma-Aldrich
Activated Charcoal Norit®, Norit® SX2, powder, from peat, multi-purpose activated charcoal, steam activated and acid washed
Supelco
Activated Charcoal Norit®, Norit® RBAA-3, rod
Sigma-Aldrich
Activated Charcoal Norit®, Norit® PK 1-3, from peat, steam activated, granular
Supelco
Activated charcoal, for the determination of AOX, 50-150 μm particle size
Sigma-Aldrich
Activated Charcoal Norit®, Norit® RB3, for gas purification, steam activated, rod
Sigma-Aldrich
Activated Charcoal, meets USP testing specifications
Sigma-Aldrich
Activated charcoal, untreated, granular, 20-60 mesh
Carbon, foil, 100x100mm, thickness 0.5mm, flexible graphite, 99.8%
Supelco
Activated charcoal, suitable for GC
Carbon, foil, 5x5mm, thickness 2.0mm, hOpg
Carbon - Vitreous, foam, 150x150mm, thickness 2.5mm, bulk density 0.05g/cm3, porosity 96.5%
Carbon, foil, 10x10mm, thickness 2.0mm, hOpg
Carbon - Vitreous, foil, 25x25mm, thickness 0.5mm, glassy carbon
Carbon, foil, 100x100mm, thickness 0.35mm, flexible graphite, 99.8%