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VOS O, BUDKE L, VERGROESEN AJ. Protection of Tissue-culture Cells against Ionizing Radiation. ACTA ACUST UNITED AC 2009; 5:543-57. [PMID: 13997936 DOI: 10.1080/09553006214551191] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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CHARLESBY A, GARRATT PG, KOPP PM. The Use of Sulphur as a Protecting Agent against Ionizing Radiations. ACTA ACUST UNITED AC 2009; 5:439-46. [PMID: 14020238 DOI: 10.1080/09553006214551061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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GRONOW M. The Effect of a Radiosensitizer and Its Tritiated Analogue on the Sulphydryl Levels of Mouse Ascites Tumourin Vivo. ACTA ACUST UNITED AC 2009; 9:123-32. [PMID: 14328332 DOI: 10.1080/09553006514550141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstracts from the 12th Annual Meeting of the Scientific Association of Swiss Radiation Oncology (SASRO), April 10-12, 2008, Lausanne. Strahlenther Onkol 2008; 184:621-41. [PMID: 19016021 DOI: 10.1007/s00066-008-1004-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Dittmann K, Mayer C, Wanner G, Kehlbach R, Rodemann HP. The radioprotector O-phospho-tyrosine stimulates DNA-repair via epidermal growth factor receptor- and DNA-dependent kinase phosphorylation. Radiother Oncol 2007; 84:328-34. [PMID: 17714814 DOI: 10.1016/j.radonc.2007.07.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 06/22/2007] [Accepted: 07/17/2007] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND PURPOSE Purpose of the study was to elucidate the underlying molecular mechanism of the radioprotector O-phospho-tyrosine (P-Tyr). METHODS Molecular effects of P-Tyr at the level of EGFR responses were investigated in vitro with bronchial carcinoma cell line A549. Nuclear EGFR transport and DNA-PK activation were quantified after Western blotting. Residual DNA-damages were quantified by help of gammaH(2)AX focus assay. RESULTS As determined by dose-response curves, treatment of cells with P-Tyr for 16h before irradiation results in radioprotection. Simultaneous treatment with EGFR blocking antibody Cetuximab abolished P-Tyr associated radioprotection. At the molecular level P-Tyr mediated a general phosphorylation of EGFR and a pronounced phosphorylation of nuclear EGFR at residue Thr No. 654, also observed after treatment with ionizing radiation. This phosphorylation was associated with nuclear EGFR accumulation. Moreover, P-Tyr-triggered EGFR nuclear accumulation was associated with phosphorylation of DNA-PK at Thr 2609. This activated form of DNA-PK was not DNA associated, but after radiation, DNA binding increased, particularly after P-Tyr pre-treatment. These molecular effects of P-Tyr resulted in a reduction of residual DNA-damage after irradiation. CONCLUSIONS Radioprotection by P-Tyr is mediated through its stimulation of nuclear EGFR transport and concurrent, but DNA-damage independent, activation of DNA-PK. Thus, subsequent irradiation results in increased binding of DNA-PK to DNA, improved DNA-repair and increased cell survival.
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Marquele-Oliveira F, Fonseca YM, de Freitas O, Fonseca MJV. Development of topical functionalized formulations added with propolis extract: stability, cutaneous absorption and in vivo studies. Int J Pharm 2007; 342:40-8. [PMID: 17600647 DOI: 10.1016/j.ijpharm.2007.04.026] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Revised: 04/20/2007] [Accepted: 04/24/2007] [Indexed: 11/16/2022]
Abstract
Propolis, which is a natural product widely consumed in the folk medicine, is a serious candidate to be applied topically due to its outstanding antioxidant properties. So, the purpose of this study was to develop stable topical formulations added with propolis extract in an attempt to prevent and/or treat the diseases occurring in skin caused by UV radiation. The antioxidant activity using a chemiluminescent method was used to evaluate the functional stability and the permeation/retention in skin of these formulations. In the long-term stability study, the formulations were stored at 25+/-2 degrees C/AH and at 40+/-2 degrees C/70% RH for 360 days. It was found in this study, that the formulations prepared with Polawax showed functional and physical stability in the period of study. In addition, this formulation presented good results in the percutaneous study, allowing the antioxidant compounds present in the propolis extract to reach lower layers in pig ear skin and in the whole hairless mice skin (retention=0.12 and 0.13 microL of propolis/g of skin, respectively). In the in vivo study, it was also suggested that this formulation may be effective in protecting skin from UVB photodamage, nevertheless other assays need to be done in order to have a complete understanding of the protective effect of formulations added with propolis extract.
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Voskanian KS, Mitsyn GV, Gaevskiĭ VN. [Radioprotective effect of helium-neon laser radiation for fibroblast cells]. AVIAKOSMICHESKAIA I EKOLOGICHESKAIA MEDITSINA = AEROSPACE AND ENVIRONMENTAL MEDICINE 2007; 41:32-5. [PMID: 17902357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Effects of combined exposure to 633-nm laser waves and gamma-radiation, and laser waves and protons with the energy of 150 MeV on survivablilty of mice fibroblast cells C3H10T1/2 were compared. Cell suspension (1 - 5 x 10(5) cells/ml) was distributed in 2-ml plastic vials with 1 cm in diameter time interval between two exposures in a combination was no more than 60 s. immediately after exposure a required quantity of cells was inoculated in special vials for survivability assessment. Based on results of the experiment, preliminary and repeated laser treatment was favorable to survivability of fibroblast cells subjected to gamma- or proton irradiation (dose variation factor was within 1.3 to 2.2). Simultaneous exposure of C3H10T1/2 cells to the laser and proton beams also increased their survivability. The radioprotective effect of the helium-neon laser on fibroblasts earlier exposed to ionizing radiation is of chief interest, as most of the present-day radioprotectors are effective only if introduced into organism prior to exposure.
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Jones JA, Riggs PK, Yang TC, Pedemonte CH, Clarke MSF, Feeback DL, Au WW. Ionizing radiation-induced bioeffects in space and strategies to reduce cellular injury and carcinogenesis. AVIATION, SPACE, AND ENVIRONMENTAL MEDICINE 2007; 78:A67-78. [PMID: 17511301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
BACKGROUND The bioeffects of space radiation on organisms outside of the environment of Earth's magnetosphere are a concern for long-duration exploration spaceflights. Potential mutagenic effects from space radiation exposure result from direct DNA damage or indirectly from the production of reactive oxygen species (ROS). HYPOTHESES 1) Transepithelial electrical resistance (TER) measurements in cell culture monolayers may be used as a model system for detecting cell damage produced by exposure to simulated space radiation and for testing potential chemoprotective agents; 2) biomarkers of exposure that quantitate indirect radiation effects may allow prediction of cellular DNA damage; and 3) a multiple agent, chemoprevention cocktail may reduce the bioeffects of simulated space radiation. METHODS Normal human and canine lung, breast, and renal epithelial cells were assayed in vitro and exposed to escalating doses of gamma or heavy-ion carbon (290 MeV/u), ceon (400 MeV/u), or iron (600 MeV/u) irradiation. Post-exposure measurements of TER, lipid peroxidation (LP) via measurement of 4-hydroxy-nonenal (4-HNE), and malonaldehyde (MDA) and assessment of chromosome damage via fluorescence in situ hybridization with tandem labeling of chromosome 1 were performed. RESULTS Cells exposed to intermediate or high doses of radiation (5, 10, and 25 Gy) showed characteristic diminution in TER, thought to be secondary to dysfunction of tight junctions, and associated with membrane LP and other mechanisms. The cells also showed increases in 4-HNE + MDA measurements and increased frequency of chromosomal aberrations. Preliminary studies of cells incubated with media containing a combination of chemoprotective agents at the time of radiation exposure showed a 15-50% reduction in the radiation-induced changes in membrane resistance, levels of LP, and chromosomal aberrations relative to their unprotected cellular counterparts. CONCLUSION TER measurement, in conjunction with measures of LP, may provide a useful model for determination of physiological changes caused by radiation exposure and the efficacy of chemoprotective agents. A multi-agent mixture of chemoprotective agents may be more effective than previously evaluated single agents alone.
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Khramov RN, Katkov YA, Kreslavskii VD, Murashev AN, Tsyganova VG, Simonova NB, Manokhin AA. Orange-red light attenuates inhibition of proliferation of rat fibroblasts induced by ultraviolet-A. DOKL BIOCHEM BIOPHYS 2007; 413:54-6. [PMID: 17546952 DOI: 10.1134/s1607672907020044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zhong YH, Han G, Zhou YF, Peng M, Xie CH, Zhou FX, Zhang WJ. [Protection of Angelica sinensis against radiation-induced pulmonary fibrosis in mice]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2007; 41:105-9. [PMID: 17605235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
OBJECTIVE To evaluate the Angelica Sinensis as a protecting agent affecting the radiation-induced pulmonary fibrosis in an animal model, METHODS The thoraces of C57BL/6 mice were exposed to either sham irradiation or single fraction of 12 Gy. Four groups were defined: that received neither irradiation nor Angelica Sinensis (N group), that received Angelica Sinensis but no irradiation (A group), that underwent irradiation without Angelica Sinensis (NX group) and that received both Angelica Sinensis and irradiation (AX group). Mice were sacrificed at 1, 24, 72 hours and 1, 2, 4, 8, 16, 24 weeks post-irradiation. The lungs tissue were removed and processed for definitive analysis, including hydroxyproline content, HE and Masson staining, and the TGF-beta1, (Transforming Growth Factor beta1, TGF-beta1) mRNA expressions. RESULTS Compared with N and A group, there was some differences in the AX group, but a significant histological and pathologic changes in NX group. Non-irradiated groups (N and A group) exhibited low levels of hydroxyproline (0.775 +/- 0.024) microg/mg and (0.751 +/- 0.034) microg/mg, and there was a significantly elevated level of hydroxyproline in NX group (0.875 +/- 0.009) microg/mg (P < 0.05). AX group (0.782 +/- 0.010) microg/mg was in between the non-irradiated groups (N and A group) and the radiation-only group (NX group), and the difference between AX group and NX group was significant (P < 0.01). The results of real-time quantitative RT-PCR showed that the relative mRNA expressions of cytokine TGF-beta1 in NX group(249.655 +/- 16.320) was significantly higher than that in group A (1.254 +/- 0.061) and N (1.324 +/- 0.057) (P < 0.01), and that in AX group (108.076 +/- 9.870) decreased than that of NX group (P < 0.01). CONCLUSION An animal model of mice with radiation-induced lung injure was established successfully. This study has demonstrated that Angelica sinensis in Hibits the progress of radiation-induced pulmonary fibrosis, Possibly by down-regulating the expression of the proinflammatory cytokine Tgfb1. These data suggest that Angelica sinensis maybe useful in preventing and/or treating radiation-induced pulmonary fibrosis in the clinic.
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SHAPIRO B, KOLLMANN G, SCHWARTZ EE. THE DISTRIBUTION AND METABOLISM OF ORALLY ADMINISTERED 2-MERCAPTOETHYLGUANIDINE (MEG) AND BIS(2-GUANIDOETHYL) DISULFIDE (GED) IN PROTECTED MICE*. Ann N Y Acad Sci 2006; 114:597-601. [PMID: 14128249 DOI: 10.1111/j.1749-6632.1964.tb53612.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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SCHWARTZ EE, SHAPIRO B, KOLLMANN G. CHEMICAL PROTECTION AGAINST RADIATION IN TUMORBEARING MICE*. Ann N Y Acad Sci 2006; 114:614-21. [PMID: 14126003 DOI: 10.1111/j.1749-6632.1964.tb53615.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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KOLLMANN G, SHAPIRO B, SCHWARTZ EE. STUDIES CONCERNING THE NATURE OF THE PROTEIN-BOUND PROTECTIVE AGENT IN THE TISSUES OF MICE GIVEN BIS(2-GUANIDOETHYL) DISULFIDE (GED)*. Ann N Y Acad Sci 2006; 114:602-6. [PMID: 14126000 DOI: 10.1111/j.1749-6632.1964.tb53613.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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NELSON A, HERTZBERG O, HENRICSSON I. RECOVERY RATE AND DOSE-REDUCTION FACTOR IN CYSTEAMINE-TREATED MICE AFTER FRACTIONATED IRRADIATION. Ann N Y Acad Sci 2006; 114:630-50. [PMID: 14126005 DOI: 10.1111/j.1749-6632.1964.tb53617.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Krafft A, Müller S, Umathum R, Semmler W, Bock M. B1 field-insensitive transformers for RF-safe transmission lines. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2006; 19:257-66. [PMID: 17115123 DOI: 10.1007/s10334-006-0055-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 10/11/2006] [Accepted: 10/12/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVE Integration of transformers into transmission lines suppresses radiofrequency (RF)-induced heating. New figure-of-eight-shaped transformer coils are compared to conventional loop transformer coils to assess their signal transmission properties and safety profile. MATERIALS AND METHODS The transmission properties of figure-of-eight-shaped transformers were measured and compared to transformers with loop coils. Experiments to quantify the effect of decoupling from the B1 field of the MR system were conducted. Temperature measurements were performed to demonstrate the effective reduction of RF-induced heating. The transformers were investigated during active tracking experiments. RESULTS Coupling to the B1 field was reduced by 18 dB over conventional loop-shaped transformer coils. MR images showed a significantly reduced artifact for the figure-of-eight- shaped coils generated by local flip-angle amplification. Comparable transmission properties were seen for both transformer types. Temperature measurements showed a maximal temperature increase of 30 K/3.5 K for an unsegmented/segmented cable. With a segmented transmission line a robotic assistance system could be successfully localized using active tracking. CONCLUSION The figure-of-eight-shaped transformer design reduces both RF field coupling with the MR system and artifact sizes. Anatomical structure close to the figure-of-eight-shaped transformer may be less obscured as with loop-shaped transformers if these transformers are integrated into e.g. intravascular catheters.
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Wraith J, Przeslawski R, Davis AR. UV-Induced Mortality in Encapsulated Intertidal Embryos: Are Mycosporine-Like Amino Acids an Effective Sunscreen? J Chem Ecol 2006; 32:993-1004. [PMID: 16739019 DOI: 10.1007/s10886-006-9054-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2005] [Revised: 01/20/2006] [Accepted: 01/24/2006] [Indexed: 11/24/2022]
Abstract
Mycosporine-like amino acids (MAAs) are believed to protect a variety of marine organisms against the negative effects of ultraviolet radiation (UVR). However, their role in protecting developing intertidal encapsulated embryos remains untested. In the present study, we focused on the UV protective role of natural concentrations of MAAs for two intertidal gastropod species, Bembicium nanum and Siphonaria denticulata, which lay egg masses in habitats exposed to direct sunlight. We predicted that in both species, a higher concentration of MAAs within the egg mass would increase the likelihood of embryonic survivorship in the presence of UVR. Egg masses from both species were collected along the rocky shores of southeastern New South Wales, and a portion from each was subjected to one of three separate spectral treatments: full spectrum, UV-B block, and UV block. Proportions of surviving embryos were recorded following 72 hr exposure to spectral treatment. In addition, MAAs in each egg mass were quantified. Levels of variation in MAA concentration were striking, with S. denticulata egg masses showing more intraspecific variation than those of B. nanum. Surprisingly, survivorship under all spectral treatments was extremely high for both species, irrespective of MAA concentration. Under full spectrum treatments, B. nanum survivorship and total MAA concentration were significantly and positively correlated; however, MAA accounted for just 23.6% (R = 0.486) of the variation in survivorship. In contrast, survivorship in S. denticulata was not correlated with MAA concentration under full spectrum light. We conclude that the dependence on MAAs as photoprotection may be species-specific; however, it is likely that both species possess alternative mechanisms that minimize the negative effects of UVR.
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Maia Campos PMBG, Gianeti MD, Kanashiro A, Lucisano-Valim YM, Gaspar LR. In Vitro Antioxidant and In Vivo Photoprotective Effects of an Association of Bioflavonoids with Liposoluble Vitamins. Photochem Photobiol 2006; 82:683-8. [PMID: 16542108 DOI: 10.1562/2005-10-14-ra-715] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A new tendency in cosmetic formulations is the association of botanical extracts and vitamins to improve skin conditions by synergic effects. The objective of this study was to determine the antioxidant activity of associated bioflavonoids, retinyl palmitate (RP), tocopheryl acetate (TA) and ascorbyl tetraisopalmitate (ATIP), as well as their photoprotective effects in preventing increased erythema, transepidermal water loss (TEWL) and sunburn cell formation in hairless mouse skin. The antioxidant activity of solutions containing the association or each substance separately was evaluated in vitro by a chemiluminescence assay. The photoprotective effect was evaluated by means of in vivo tests. Dorsal skin of hairless mice was treated daily by topical applications for 5 days with formulations containing or not containing (vehicle) the flavonoid-vitamins association (5%). The skin was irradiated (UVA/B) 15 minutes after the last application. The results showed that bioflavonoids had in vitro antioxidant properties and also that when they were associated with vitamins their antioxidant activity was more pronounced. On the other hand, erythema and UV damage to the permeability barrier function (TEWL) was not significantly reduced by previous treatment with the flavonoid-vitamin-association formulations, when compared to the irradiated vehicle-treated area. However, the treatment protected the skin from UV damage because it reduced the number of sunburn cells, when compared to the vehicle-treated area. Finally, the association of vitamins and bioflavonoids added to a dermocosmetic formulation showed a relevant biological activity in terms of photoprotection, because the association of bioflavonoids and vitamins acted by different mechanisms, such as antioxidation and absorption of UV radiation, which suggests its use in antiaging and photoprotective products.
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Weiss S, Vernickel P, Schaeffter T, Schulz V, Gleich B. Transmission line for improved RF safety of interventional devices. Magn Reson Med 2005; 54:182-9. [PMID: 15968655 DOI: 10.1002/mrm.20543] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A new concept is proposed to improve the safety of transmission lines with respect to heating during RF transmission. It is based on the integration of transformers into the transmission line. The concept was applied to an active tracking device. Miniature transformers were designed, and two types of tracking devices were built based on a standard line and a transformer line. Temperature measurements were performed for both devices during high specific absorption rate (SAR) scanning, and the suppression of RF heating to a physiologically non-relevant level was demonstrated for the transformer device. The transmission properties of the transformer line were examined in simulations and RF measurements. Active tracking with the transformer device performed robustly in the phantom. Because of the favorable signal transmission properties of the tested device, it is expected that the concept can be applied to the construction of clinical devices for tracking and intravascular imaging, which are RF-safe under clinical SAR conditions. Since the transformer line has a large bandwidth, the concept may also be applied for RF-safe transmission of non-MR signals.
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Kouloulias VE, Kouvaris JR, Pissakas G, Mallas E, Antypas C, Kokakis JD, Matsopoulos G, Michopoulos S, Mystakidou K, Vlahos LJ. Phase II multicenter randomized study of amifostine for prevention of acute radiation rectal toxicity: topical intrarectal versus subcutaneous application. Int J Radiat Oncol Biol Phys 2005; 62:486-93. [PMID: 15890591 DOI: 10.1016/j.ijrobp.2004.10.043] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2003] [Revised: 10/08/2004] [Accepted: 10/14/2004] [Indexed: 02/02/2023]
Abstract
PURPOSE To investigate the cytoprotective effect of subcutaneous vs. intrarectal administration of amifostine against acute radiation toxicity. METHODS AND MATERIALS Patients were randomized to receive amifostine either intrarectally (Group A, n = 27) or a 500-mg flat dose subcutaneously (Group B, n = 26) before irradiation. Therapy was delivered using a four-field technique with three-dimensional conformal planning. In Group A, 1,500 mg of amifostine was administered intrarectally as an aqueous solution in 40 mL of enema. Two different toxicity scales were used: the European Organization for Research and Treatment of Cancer/Radiation Therapy Oncology Group (RTOG) rectal and urologic toxicity criteria and the Subjective-RectoSigmoid scale based on the endoscopic terminology of the World Organization for Digestive Endoscopy. Objective measurements with rectosigmoidoscopy were performed at baseline and 1-2 days after radiotherapy completion. The area under the curve for the time course of mucositis (RTOG criteria) during irradiation represented the mucositis index. RESULTS Intrarectal amifostine was feasible and well tolerated without any systemic or local side effects. According to the RTOG toxicity scale, Group A had superior results with a significantly lower incidence of Grades I-II rectal radiation morbidity (11% vs. 42%, p = 0.04) but inferior results concerning urinary toxicity (48% vs. 15%, p = 0.03). The mean rectal mucositis index and Subjective-RectoSigmoid score were significantly lower in Group A (0.44 vs. 2.45 [p = 0.015] and 3.9 vs. 6.0 [p = 0.01], respectively), and the mean urinary mucositis index was lower in Group B (2.39 vs. 0.34, p < 0.028). CONCLUSIONS Intrarectal administration of amifostine (1,500 mg) seemed to have a cytoprotective efficacy in acute radiation rectal mucositis but was inferior to subcutaneous administration in terms of urinary toxicity. Additional randomized studies are needed for definitive decisions concerning the cytoprotection of pelvic irradiated areas.
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Satoh E, Yan H, Miyagi T, Li XK, Sugiura W, Yamamoto N, Teramoto K, Arii S, Kimura H. Studies on the most efficient vector systems for gene transduction into dendritic cells. Transplant Proc 2005; 37:12-4. [PMID: 15808530 DOI: 10.1016/j.transproceed.2004.12.234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Specialized antigen-presenting cells (APC), known as dendritic cells (DC), play a pivotal role in initiating primary immune responses. Several vector systems, including adenoviral vectors, retroviral vectors, hemagglutinating virus of Japan-related vectors, and the electroporation, have been shown to transduce genes into mouse and human but not rat DC. However, there is no direct evidence to support the view that the currently used vector systems are able to transduce genes into mature DC. Inasmuch as most, if not all, gene transfer studies investigating DC or DC-related cell populations are performed employing heterogeneous-groups of cells, it is therefore important to determine the extent to which gene transduction occurs in bona fide DC. In this study, we provide evidence that none of these vector systems are able to transfer genes into mature rat DC, which are derived from bone marrow cells (BMC), driven by Flt3/Flk2 ligand and IL-6, and purified with CD161a. Nevertheless, the most efficient gene transduction was observed with developing DC progenitor cells during long-term culture of rat BMC. Successful gene transfer was achieved after 2-week culture with an HIV-based lentiviral vector system.
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Songthaveesin C, Saikhun J, Kitiyanant Y, Pavasuthipaisit K. Radio-protective effect of vitamin E on spermatogenesis in mice exposed to gamma-irradiation: a flow cytometric study. Asian J Androl 2004; 6:331-6. [PMID: 15546025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023] Open
Abstract
AIM To investigate the effect of vitamin E on the radioprotection of spermatogenesis and chromatin condensation of spermatozoa during passage through the epididymis in mice exposed to irradiation. METHODS Adult outbred male ICR mice were orally administered natural vitamin E (VE, D-alpha-tocopheryl acetate) at 400 IU/kg for 7 days before exposure to 1 Gy of gamma-irradiation. The animals were sacrificed at day 1, 7, 14, 21, 28, 35 and 70 post-irradiation (IR) and the percentage of testicular germ cells and epididymal sperm chromatin condensation was analyzed using flow cytometry. RESULTS Serum D-alpha-tocopheryl acetate levels were 47.4+/-3.2 microg/dL in the treated group, yet it could not be detected in the control group. The testicular weight of irradiated mice pretreated with VE+IR was significantly (P<0.05) higher than that of those without VE treatment (IR) at day 14 and 21 post-irradiation. The percentage of primary spermatocytes (4C) in the VE+IR group was comparable to the controls but significantly (P<0.05) higher than those in the IR group from day 7 to 35 post-irradiation. The percentage of round spermatids (1C) in the VE+IR group was also significantly (P<0.05) higher than those in the IR group at day 28 post-irradiation. The primary spermatocytes : spermatogonia ratio in the IR group was significantly (P<0.05) declined at day 7 to 35 post-irradiation when compared to the VE+IR and control groups. The round spermatid : spermatogonia ratio in the VE+IR group was significantly (P<0.05) higher than that of the IR group at day 14 and 28 post-irradiation. The chromatin condensation of epididymal spermatozoa measured by propidium iodide uptake was not affected by 1 Gy of gamma-irradiation. CONCLUSION The administration of VE prior to irradiation protects spermatogenic cells from radiation.
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Mahé E, Morelon E, Fermanian J, Lechaton S, Pruvost C, Ducasse MF, Mamzer-Bruneel MF, Kreis H, Bodemer C, de Prost Y. Renal-Transplant Recipients and Sun Protection. Transplantation 2004; 78:741-4. [PMID: 15371679 DOI: 10.1097/01.tp.0000131818.24302.b8] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The incidence of skin carcinomas in organ-transplant recipients is high. The main factors implicated in carcinogenesis are immune suppression and ultraviolet radiation. Only the second is avoidable. We have evaluated knowledge of and compliance with sun protection measures among renal-transplant recipients (RTR). METHODS A survey by means of a questionnaire including questions about clinical data, knowledge of, and compliance with sun protection was given. The questionnaire was given to 520 consecutive RTR followed up in a single center, and 445 (86%) answered. RESULTS Of the responders, 91% have been informed of the need for sun protection, in 80% of cases by dermatologists. Sixty-eight percent used more protective measures abroad than at home, 63% avoided going outside during the hottest midday hours, 63% used sunscreen regularly, but 46% used one or less tube of sunscreen a year. A hat was always worn in the sun by 35% and long sleeves by 36%. Women and fair-skinned individuals complied better with protective measures. A minority of patients knew that ultraviolet radiation carries a risk of skin cancer. CONCLUSIONS This survey shows that most RTR are aware of the need for sun protection, but only a minority take adequate protection measures. The better results observed in this study than in previous published investigations may be caused by the great involvement of dermatologists in the care of RTR in our institution. The results of this survey underline the need to inform RTR better about sun-protection measures and the importance of cooperation between transplant physicians and dermatologists.
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75
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Sener G, Jahovic N, Tosun O, Atasoy BM, Yeğen BC. Melatonin ameliorates ionizing radiation-induced oxidative organ damage in rats. Life Sci 2004; 74:563-72. [PMID: 14623027 DOI: 10.1016/j.lfs.2003.05.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study was designed to study the effects of the potential radioprotective properties of pharmacological doses of melatonin against organ damage induced by whole-body irradiation (IR) in rats. A total of 32 male Sprague-Dawley rats were exposed to irradiation performed with a LINAC producing 6 MV photons at a focus 100 cm distant from the skin. Under ketamine anaesthesia, each rat received a single whole-body dose of 800 cGy. Immediately before and after IR, rats were treated with either saline or melatonin (20 mg/kg and 10 mg/kg, i.p.) and decapitated at 12-h after exposure to irradiation. Another group of rats was followed for 72-h after IR, where melatonin (10 mg/kg, i.p.) injections were repeated once daily. Tissue levels of malondialdehyde (MDA)--an index of lipid peroxidation--, glutathione (GSH)--a key to antioxidant--and myeloperoxidase (MPO) activity--an index of neutrophil infiltration--were estimated in liver, lung, colon and intestinal tissues. The results demonstrate that both 12-h and 72-h following IR, tissue levels of MDA were elevated (p<0.05-0.001), while GSH levels were reduced (p<0.05-0.001) in all organs. On the other hand, melatonin, reduced the levels of MDA and increased the GSH levels significantly, (p<0.05-0.001). MPO activity was increased significantly in the colonic tissue at the both 12-h and 72-h, and in the hepatic tissue at the 72-h following IR, which were reduced by melatonin (p<0.01-0.001). In the lung tissue enzyme activity was decreased at 72nd h of post-irradiation. In conclusion, the increase in MDA levels and MPO activity and the concomitant decrease in GSH levels demonstrate the role of oxidative mechanisms in irradiation-induced tissue damage, and melatonin, by its free radical scavenging and antioxidant properties, ameliorates irradiation-induced organ injury. Thus, supplementing cancer patients with adjuvant therapy of melatonin may have some benefit for successful radiotherapy.
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76
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Badzhinian SA, Kazarian SA, Grigorian RM, Saiadian AV, Sarkisian NK, Gasparian GG. [New Mn-chelates are radioprotectors and antioxidants for cells in vitro]. RADIATSIONNAIA BIOLOGIIA, RADIOECOLOGIIA 2004; 44:72-5. [PMID: 15060945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Earlier we have synthesized new Mn-chelates (Mn-compexes of ethyl ethers of salicyliden-D, L-tyrosine, -gamma-amino butyric acid and -D, L-tryptophan) bearing several free functional groups. The radioprotective and antioxidant activity of these compounds were tested on the secondary cultures of chick embryo cells. To this end the cells in vitro were gamma-irradiated with 60Co at the doses 40 and 60 Gy or treated with H2O2 at the concentration 3 mmol/l, the new Mn-chelates were added into the cultures, and the number of survived cells was determined in 24 hours. It was revealed that all the new Mn-chelates at micromolar concentrations (from 40 to 10 mumol/l) but not their precursors (Mn-acetate and ethyl ethers of salicyliden-aminoacids) effectively protect the cells from lethal effect of both gamma-irradiation and H2O2. Mn-chelates tested are considered as promising potential radioprotectors that effect seems to be reasonable to study in vivo.
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Abstract
The concept of "brain death" was introduced to medicine in the second half of the 20th century, when technological advancements began to allow sustaining cardiorespiratory functioning of the body in the absence of brain function. Although physicians generally agree that a patient can be declared brain dead when the loss of brain function is total and irreversible, different approaches have been taken to define what constitutes brain death. A thorough clinical examination is essential to the diagnosis. The role of confirmatory tests differ among countries in the world but generally are indicated when a specific part of the clinical examination cannot be performed or is deemed unreliable. Under certain circumstances, confirmatory tests can be used to shorten the clinical observation. Of the confirmatory tests recommended by the American Academy of Neurology and the American Academy of Pediatrics, cerebral scintigraphy is a safe, reliable, and widely available alternative. Once the radiopharmaceutical is properly compounded, cerebral scintigraphy can be performed rapidly and can be interpreted in a straightforward manner. It is tolerant of metabolic aberrations and pharmacologic intoxicants. It is not affected by electrical interference, and the presence of skull defects or scalp trauma do not preclude its performance. The radiopharmaceuticals used in scintigraphy have no deleterious effects on potential donor organs. Cerebral radionuclide angiography has been highly sensitive. Either cerebral planar scintigraphy or cerebral scintitomography with Tc-99m hexamethylpropyleneamineoxime also are highly sensitive, but, in addition, appear to be 100% specific.
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78
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Isobe S, Ando A, Nanasato M, Nonokawa M, Izawa H, Sobue T, Hirai M, Ito K, Ishigaki T, Murohara T, Yokota M. Combined study with FDG PET and Tl SPECT in patients with idiopathic dilated cardiomyopathy. Nucl Med Commun 2003; 24:1071-80. [PMID: 14508163 DOI: 10.1097/00006231-200310000-00007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This study aimed to determine whether combined examinations of myocardial 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and stress-redistribution 201Tl single-photon emission computed tomography (Tl SPECT) were useful in clarifying myocardial ischaemia and evaluating the prognosis in patients with idiopathic dilated cardiomyopathy (IDCM). Twenty-two patients with IDCM underwent echocardiography, cardiac catheterization, FDG PET, and Tl SPECT. In scintigraphic analysis, the total defect score (TDS) was semiquantitatively determined as the sum of scores of the 17 left ventricular (LV) segments with a 5-point scale (0 as normal to 4 as absent). Patients were classified according to the scintigraphic findings as follows: eight patients with small defects on Tl and FDG (TDS < or = 20) (group I), eight patients with small defects on FDG (TDS < or = 20) with FDG uptake increased relative to Tl or 'mismatch' (group II), and six patients with large defects on FDG and Tl (TDS >20) (group III). Eleven patients (50%) showed reversible defects on Tl and all showed preserved FDG uptake. The patients in group III had significantly lower LV ejection fraction (LVEF) (P<0.05, respectively) and a poorer prognosis as shown by the Kaplan-Meier event-free curve compared with those in groups I and II (P<0.01, respectively). Although patients in group II had significantly greater TDS on Tl compared with those in group I (P<0.01), no significant differences in LVEF and prognosis were found between patients in groups I and II. In multivariate analysis, a TDS on FDG revealed an independent predictor of subsequent cardiac events. In conclusion, such mismatched areas can be assumed to consist of impaired but viable myocardium, and may be associated with ischaemia of the microvasculature. Impaired myocardial glucose metabolism is a more powerful predictor of future cardiac events than perfusion abnormality in patients with IDCM.
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MESH Headings
- Age Factors
- Cardiomyopathy, Dilated/complications
- Cardiomyopathy, Dilated/diagnosis
- Cardiomyopathy, Dilated/diagnostic imaging
- Diagnosis, Differential
- Disease-Free Survival
- Female
- Fluorodeoxyglucose F18
- Humans
- Image Enhancement/methods
- Male
- Middle Aged
- Myocardial Ischemia/complications
- Myocardial Ischemia/diagnosis
- Myocardial Ischemia/diagnostic imaging
- Prognosis
- Radiation-Protective Agents
- Reproducibility of Results
- Risk Assessment/methods
- Sensitivity and Specificity
- Sex Factors
- Tomography, Emission-Computed/methods
- Tomography, Emission-Computed, Single-Photon/methods
- Ventricular Dysfunction, Left/diagnosis
- Ventricular Dysfunction, Left/diagnostic imaging
- Ventricular Dysfunction, Left/etiology
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79
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Gupta D, Arora R, Garg AP, Goel HC. Radiation protection of HepG2 cells by Podophyllum hexandrum Royale. Mol Cell Biochem 2003; 250:27-40. [PMID: 12962140 DOI: 10.1023/a:1024925612233] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Radioprotection by an aqueous extract of Podophyllum hexandrum (RP-1) was investigated in HepG2 cells by evaluating colony forming efficacy (CFE), redox status of mitochondria, reactive oxygen species (ROS), generation of nitric oxide (NO), peroxidation of lipids and intracellular glutathione. Lower concentrations of RP-1 (0.1 and 1 microg/ml) rendered maximum radioprotection when administered 1 or 2 h before irradiation. Higher concentrations (5 and 10 microg/ml) however were less effective when administered 1 or 2 h before irradiation, but were more effective with increased time intervals (4 or 8 h) between RP-1 administration and irradiation. RP-1 pre-treatment also significantly inhibited radiation-induced MTT reduction in a concentration and time-dependent manner by decreasing gamma radiation-induced leakage of electrons from electron transport chain. Pre-irradiation administration of RP-1 significantly reduced both ROS and NO generation and enhanced glutathione levels, thereby inhibiting lipid peroxidation.
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80
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Royes LFF, Fighera MR, Furian AF, Oliveira MS, da Silva LGM, Malfatti CRM, Schneider PH, Braga AL, Wajner M, Mello CF. Creatine protects against the convulsive behavior and lactate production elicited by the intrastriatal injection of methylmalonate. Neuroscience 2003; 118:1079-90. [PMID: 12732252 DOI: 10.1016/s0306-4522(02)00978-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Methylmalonic acidemias are metabolic disorders caused by a severe deficiency of methylmalonyl-CoA mutase activity, which are characterized by neurological dysfunction, including convulsions. It has been reported that the accumulating metabolite, L-methylmalonic acid (MMA), inhibits succinate dehydrogenase leading to ATP depletion in vitro, and that the intrastriatal injection of MMA induces convulsions through secondary NMDA receptor stimulation. In this study we investigated the effect of creatine (1.2, 3.6 and 12.0 mg/kg, (i.p.), [DOSAGE ERROR CORRECTED] succinate (1.5 micromol/striatum) and MK-801 (3 nmol/striatum) on the convulsions and on the striatal lactate increase induced by MMA (4.5 micromol/striatum) in rats. The effect of creatine on the striatal phosphocreatine content and on MMA-induced phosphocreatine depletion was also evaluated. Creatine, succinate and MK-801 pretreatment decreased the number and duration of convulsive episodes and the lactate increase elicited by MMA. Creatine, but not succinate, prevented the convulsions and the lactate increase induced by the direct stimulation of NMDA receptors. Acute creatine administration increased the total striatal phosphocreatine content and prevented MMA-induced phosphocreatine depletion. Our results suggest that MMA increases lactate production through secondary NMDA receptor activation, and it is proposed that the anticonvulsant effect of creatine against MMA-induced convulsions may be due to an increase in the phosphocreatine content available for metabolic purposes.
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81
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Cai L, Cherian MG. Zinc-metallothionein protects from DNA damage induced by radiation better than glutathione and copper- or cadmium-metallothioneins. Toxicol Lett 2003; 136:193-8. [PMID: 12505272 DOI: 10.1016/s0378-4274(02)00359-4] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Protection of radiation-induced DNA damage by metallothionein (MT) has been documented, but there is no detailed information about its efficiency compared to other antioxidants or the effect of metals which bind to MT on the protective effect of MT in radiation-induced DNA damage. In this study, we used a cell-free system to investigate the effect of MT with other antioxidants, such as albumin and glutathione and we compared the efficiency of MT bound to different metals on radiation-induced DNA damage. DNA damage was measured by loss in ethidium bromide/DNA fluorescence and increased mobility of DNA on gel electrophoresis. Gamma rays at 30 Gy induced significant DNA damage and zinc-MT showed a significant higher protection from radiation-induced DNA damage than both glutathione and albumin. Metallothionein bound to other metals, such as copper and cadmium, also showed protection of radiation-induced DNA damage, but the protective effect by zinc-MT was the highest. These results suggest that MT, in particular bound to zinc, is a high-capacity antioxidant to protect radiation-induced DNA damage.
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82
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Epperly MW, Guo HL, Jefferson M, Nie S, Gretton J, Bernarding M, Bar-Sagi D, Archer H, Greenberger JS. Cell phenotype specific kinetics of expression of intratracheally injected manganese superoxide dismutase-plasmid/liposomes (MnSOD-PL) during lung radioprotective gene therapy. Gene Ther 2003; 10:163-71. [PMID: 12571645 DOI: 10.1038/sj.gt.3301852] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Intratracheal (IT) injection of manganese superoxide dismutase-plasmid/liposome (MnSOD-PL) complexes prior to whole lung irradiation of C57BL/6J mice provides significant protection from acute and chronic irradiation damage. We determined the duration of increased MnSOD biochemical activity and differential expression of a hemagglutinin (HA) epitope-tagged MnSOD transgene. HA-MnSOD-PL was IT injected at doses of 0-1000 microg, and mice were killed 1,2,3 or 4 days later. Other groups of mice were irradiated to 20 Gy to the pulmonary cavity 24 h after injection and killed at the same time points as non-irradiated mice. Both non-irradiated and irradiated groups of mice showed increased MnSOD biochemical activity with plasmid dose that plateaued at 100 microg of MnSOD plasmid DNA. In control mice, MnSOD biochemical activity decreased at 2, 3 or 4 days after injection. In irradiated mice, MnSOD biochemical activity decreased at day 2 but increased on days 3 and 4. HA-MnSOD expression decreased in broncheoalveolar macrophages and alveolar type-II cells 3 days after injection in non-irradiated and irradiated mice, but remained elevated in endothelial and epithelial cells past 4 days. The data provide a rationale for every second-day administration of intrapulmonary MnSOD-PL in clinical trials of radioprotective gene therapy. This should be sufficient to provide radioprotection during radiation treatments.
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83
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Kanai AJ, Zeidel ML, Lavelle JP, Greenberger JS, Birder LA, de Groat WC, Apodaca GL, Meyers SA, Ramage R, Epperly MW. Manganese superoxide dismutase gene therapy protects against irradiation-induced cystitis. Am J Physiol Renal Physiol 2002; 283:F1304-12. [PMID: 12426235 DOI: 10.1152/ajprenal.00228.2002] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Urinary bladder cystitis occurs in patients receiving radiation therapy for pelvic tumors. Radiation-induced formation of superoxide radicals is believed to damage the urothelium, exposing the underlying bladder smooth muscle to urine, culminating in nerve irritation and muscle dysfunction. We tested whether overexpression of MnSOD could decrease superoxide levels and protect the bladder from radiation damage. Pelvic irradiation led to sloughing of urothelial umbrella cells, with decreased transepithelial resistance, increased water and urea permeabilities, and increased expression of inducible nitric oxide synthase. Six months after irradiation, cystometrograms showed elevated intravesical pressures and prolonged voiding patterns. However, urothelia transfected with the MnSOD transgene recovered from radiation injury more rapidly, and detrusor function was much closer to that of control bladders than irradiated bladders without the transgene. We conclude that MnSOD gene therapy is protective, which could lead to its use in mitigating radiation cystitis and preventing dysfunction of the urinary bladder.
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84
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Hoekstra O. [Netherlands' experience in positron emission tomography in thoracic oncology]. REVUE DE PNEUMOLOGIE CLINIQUE 2002; 58:3S25-3S27. [PMID: 12538930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
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85
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Hantke B, Lahmann C, Venzke K, Fischer T, Kocourek A, Windsor LJ, Bergemann J, Stäb F, Tschesche H. Influence of flavonoids and vitamins on the MMP- and TIMP-expression of human dermal fibroblasts after UVA irradiation. Photochem Photobiol Sci 2002; 1:826-33. [PMID: 12656486 DOI: 10.1039/b207731k] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
UV irradiation leads to distinct changes in skin connective tissue by degradation of collagen, for example. Many of these alterations in the extracellular matrix are mediated by MMPs (matrix metalloproteinases) with reduced content of their antagonist TIMPs (tissue inhibitors of metalloproteinases). Potential candidates to reduce MMP activity in the skin after solar stimulation were examined. The influence of vitamin C, vitamin E and the flavonoids AGR (alpha-glucosylrutin) and 8-prenylnaringenine on the MMP and TIMP expression was investigated. Human dermal fibroblasts were incubated with these additives and irradiated with UVA [10 J cm(-2)]. The gene expression of MMP-1 (collagenase-1) and TIMP-1, the protein expression of MMP-1, MMP-2 (gelatinase-A), TIMP-1 and TIMP-2 as well as the enzyme activity of MMP-1 and MMP-2 were examined. AGR and vitamins C and E were shown to reduce MMP expression and activity, whereas 8-prenylnaringenine appeared to be responsible for the opposite effect. None of the substances considerably influenced the TIMP levels. AGR represented the most effective additive in reducing the collagenase protein expression to 60% and may be useful to level out the MMP activity in the skin after sun exposure. Furthermore, no protein expression of MMP-8, MMP-9, MMP-12 and MMP-13 could be detected.
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86
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Maddens S, Charruyer A, Plo I, Dubreuil P, Berger S, Salles B, Laurent G, Jaffrézou JP. Kit signaling inhibits the sphingomyelin-ceramide pathway through PLC gamma 1: implication in stem cell factor radioprotective effect. Blood 2002; 100:1294-301. [PMID: 12149210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023] Open
Abstract
Previous studies demonstrated that Kit activation confers radioprotection. However, the mechanism by which Kit signaling interferes with cellular response to ionizing radiation (IR) has not been firmly established. Based on the role of the sphingomyelin (SM) cycle apoptotic pathway in IR-induced apoptosis, we hypothesized that one of the Kit signaling components might inhibit IR-induced ceramide production or ceramide-induced apoptosis. Results show that, in both Ba/F3 and 32D murine cell lines transfected with wild-type c-kit, stem cell factor (SCF) stimulation resulted in a significant reduction of IR-induced apoptosis and cytotoxicity, whereas DNA repair remained unaffected. Moreover, SCF stimulation inhibited IR-induced neutral sphingomyelinase (N-SMase) stimulation and ceramide production. The SCF inhibitory effect on SM cycle was not influenced by wortmannin, a phosphoinositide-3 kinase (PI3K) inhibitor. The SCF protective effect was maintained in 32D-KitYF719 cells in which the PI3K/Akt signaling pathway is abolished due to mutation in Kit docking site for PI3K. In contrast, phospholipase C gamma (PLC gamma) inhibition by U73122 totally restored IR-induced N-SMase stimulation, ceramide production, and apoptosis in Kit-activated cells. Moreover, SCF did not protect 32D-KitYF728 cells (lacking a functional docking site for PLC gamma 1), from IR-induced SM cycle. Finally, SCF-induced radioprotection of human CD34(+) bone marrow cells was also inhibited by U73122. Altogether, these results suggest that SCF radioprotection is due to PLC gamma 1-dependent negative regulation of IR-induced N-SMase stimulation. Beyond the scope of Kit-expressing cells, it suggests that PLC gamma 1 status could greatly influence the post-DNA damage cellular response to IR, and perhaps, to other genotoxic agents.
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87
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NIGROVIC V. Retention of Radiocaesium by the Rat as Influenced by Prussian Blue and Other Compounds. Phys Med Biol 2002; 10:81-92. [PMID: 14254500 DOI: 10.1088/0031-9155/10/1/308] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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88
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Cheong N, Zeng ZC, Wang Y, Iliakis G. Evidence for factors modulating radiation-induced G2-delay: potential application as radioprotectors. Phys Med 2002; 17 Suppl 1:205-9. [PMID: 11776263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Manipulation of checkpoint response to DNA damage can be developed as a means for protecting astronauts from the adverse effects of unexpected, or background exposures to ionizing radiation. To achieve this goal reagents need to be developed that protect cells from radiation injury by prolonging checkpoint response, thus promoting repair. We present evidence for a low molecular weight substance excreted by cells that dramatically increases the duration of the G2-delay. This compound is termed G2-Arrest Modulating Activity (GAMA). A rat cell line (A1-5) generated by transforming rat embryo fibroblasts with a temperature sensitive form of p53 plus H-ras demonstrates a dramatic increase in radiation resistance after exposure to low LET radiation that is not associated with an increase in the efficiency of rejoining of DNA double strand breaks. Radioresistance in this cell line correlates with a dramatic increase in the duration of the G2 arrest that is modulated by a GAMA produced by actively growing cells. The properties of GAMA suggest that it is a low molecular weight heat-stable peptide. Further characterization of this substance and elucidation of its mechanism of action may allow the development of a biological response modifier with potential applications as a radioprotector. GAMA may be useful for protecting astronauts from radiation injury as preliminary evidence suggests that it is able to modulate the response of cells exposed to heavy ion radiation, similar to that encountered in outer space.
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89
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Koc M, Buyukokuroglu ME, Taysi S. The effect of melatonin on peripheral blood cells during total body irradiation in rats. Biol Pharm Bull 2002; 25:656-7. [PMID: 12033509 DOI: 10.1248/bpb.25.656] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Melatonin, has been reported to participate in the regulation of a number of important physiological and pathological process. It has also the ability to protect the genetic material of hematopoietic cells of mice from damaging effects of acute total body irradiation. The objective of this study was to the potential radioprotective effects of pharmacological doses of melatonin in total body irradiated rat's peripheral blood cells. Forty adult rats were divided into 4 equal groups. Group 1 received no melatonin or irradiation (control group), while group 2 received only melatonin (5 mg/kg, i.p.). Group 3 received only total body irradiation (RT) by 5 Gy of gamma irradiation only and group 4 received RT plus melatonin (5 mg/kg, i.p., 30 min before RT). An hour and a half following RT, blood samples were taken. Leukocytes and thrombocytes number and hemoglobin levels were measured in all groups. Five mg/kg dose of melatonin significantly protected leukocytes and as well as thrombocytes number against y irradiation. There were no significant differences between Hb levels. Our results suggest that melatonin administration prior to irradiation prevented radiation damage on peripheral blood cells. Melatonin radioprotection is achieved by its ability as a scavenger for free radicals generated by ionizing radiation and acts probably as a growth factor, especially for granulocytes in bone marrow.
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90
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91
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ATKINSON ER, HANDRICK GR, BRUINI RJ, GRANCHELLI FE. Potential Antiradiation Drugs. I. Amide, Hydroxamic Acid, and Hydrazine Derivatives of Mercapto Acids. Amino Thioacids1. J Med Chem 2002; 8:29-33. [PMID: 14287262 DOI: 10.1021/jm00325a007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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92
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FOYE WO, MICKLES J, DUVALL RN, MARSHALL JR. Antiradiation Compounds. IV. Trithiocarbonates of β-Mercaptoethylguanidines1. J Med Chem 2002; 6:509-12. [PMID: 14173570 DOI: 10.1021/jm00341a008] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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93
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CAMPAIGNE E, NARGUND PK. 3-Alkyl-1,3-thiazane Derivatives and Precursors as Antiradiation Agents1. J Med Chem 2002; 7:132-5. [PMID: 14187362 DOI: 10.1021/jm00332a003] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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94
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FIELD L, FERRETTI A, CRENSHAW RR, OWEN TC. Organic Disulfides and Related Substances. IX.1a Symmetrical Aminothiolsulfonates as Antiradiation Drugs1b. J Med Chem 2002; 7:39-44. [PMID: 14186022 DOI: 10.1021/jm00331a009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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95
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Goncharenko EN, Deev LI, Kostanian IA, Astapova MV, Akhalaia MI, Kudriashova NI, Surina EA. [Synthetic peptides -- analogs of biologically active fragment of the differentiation factor from HL-60 cells show radioprotective and adaptogenic activities]. RADIATSIONNAIA BIOLOGIIA, RADIOECOLOGIIA 2002; 42:164-8. [PMID: 12004612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
It was shown that the addition of synthetic six-membered peptide (HLDF-6) and its Tyr-analog (HLDF-Y) to cultural medium significantly increased the survival of cells HL-60, treated by cold shock. The prophylactic administration of HDLF-Y (1 mg/kg, 4 hours prior to applied actions) decreased the response of hypothalamushypophysis-adrenal glands system and sympathicoadrenal system of rat males on supercooling and also increased the resistance of mouse males to supercooling and X-irradiation. In the experiences with females HDLF-Y did not show the similar biological activity.
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96
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Kojima Y, Kondo T, Zhao QL, Shoji M, Futatsuya R. Protective effects of cimetidine on radiation-induced micronuclei and apoptosis in human peripheral blood lymphocytes. Free Radic Res 2002; 36:255-63. [PMID: 12071343 DOI: 10.1080/10715760290019264] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The radioprotective effects of cimetidine, which has been used clinically as an antagonist of H2 receptor, on radiation-induced micronuclei and apoptosis in human peripheral blood lymphocytes (PBL) prepared from healthy donors were studied. Cells were treated with cimetidine before or after X-irradiation, and then cytokinesis-blocked micronucleus assay and flow cytometry for measurement of phosphatidylserine externalization were utilized to evaluate the radiation-induced cytogenetic damage and apoptosis. The protective effect of preirradiation treatment of cimetidine on radiation-induced micronuclei was dependent on the concentration. The maximum protection rates of cimetidine (1 mM) on frequencies of micronuclei were 38.8 and 30.2% for cells treated before and after X-irradiation (5 Gy), respectively. Protective effects of pre- and post-irradiation treatment with cimetidine on radiation-induced early apoptosis and decreased activity of caspase-3 were observed. A study of electron paramagnetic resonance-spin trapping with 5,5'-dimethyl-1-N-oxide revealed that the rate constant of cimetidine with radiation-induced OH radicals is about 4.5 x 10(9) l/mol/s. Cimetidine did not significantly increase the intracellular concentration of glutathione. These results suggest that cimetidine suppresses radiation-induced micronuclei and apoptosis via OH radical scavenging and an intracellular antioxidation mechanism. Cimetidine appears to be a useful candidate for the future development of post-irradiation radioprotectors.
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97
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Ramaĭia LK, Pomerantseva MD, Malashenko AM. [Effects of para-aminobenzoic acid on radiosensitivity of mice of different strains]. RADIATSIONNAIA BIOLOGIIA, RADIOECOLOGIIA 2002; 42:169-72. [PMID: 12004613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The aim of the work was to study the possible protective effect of para-aminobenzoic acid (PABA) on the radiation lethality in mice of three inbred lines (BALB/cLacY, C3H/HeY, 101/Hy), stock YT1 and hybrids (C3H/He x 101/H)F1. The PABA solution was given to the mice intraperitoneally in single doses of 10, 50 and 100 mg/kg 40-50 min prior to irradiation with doses of 6 to 8 Gy depending on the line and sex of mice. The used doses of gamma-radiation were roughly LD75/30. The radioprotective effect of PABA was observed in all variants of the experiment but it was relatively low. The protection coefficient varied from 0 to 0.45. The protective effect depended on the line and sex of mice and on the dose of the injected substance.
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98
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Seed TM, Fry SA, Neta R, Weiss JF, Jarrett DG, Thomassen D. Prevention and treatments: summary statement. Mil Med 2002; 167:87-93. [PMID: 11873527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
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99
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Mitchell JB, Krishna MC. Nitroxides as radiation protectors. Mil Med 2002; 167:49-50. [PMID: 11873514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Selective protection of normal tissues from the damaging effects of ionizing radiation is an important objective in cancer treatment research. Likewise, radioprotective agents may be useful in protecting the human population in the event of radiation-related accidents or military conflicts. Over the past decade, we have identified stable nitroxide compounds as a unique class of antioxidants with demonstrated radioprotective properties. We have shown that nitroxides at nontoxic concentrations are effective as in vitro and in vivo antioxidants when oxidation is induced by superoxide, hydrogen peroxide, organic hydroperoxides, ionizing radiation, or specific DNA-damaging anticancer agents. Studies have shown that nitroxides protect against radiation-induced DNA damage, chromosome aberrations, mutation induction, cell killing, and lethality in mice that receive whole-body irradiation. Whether these agents provide radioprotection for low-level radiation doses remains to be determined.
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100
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Prorokov VV, Zalit NI, Knysh VI, Barkanov AI, Anan'ev VS. [Intensive preoperative hypoxic radiotherapy in combined treatment of patients with cancer of the colon]. Khirurgiia (Mosk) 2002:38-42. [PMID: 11517699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Efficacy of combined treatment (203 patients) and surgical treatment (200 patients) alone was analyzed. In combined treatment either radiation therapy (RT) in the dose 20 Gy over 5 days (group 1) or hypoxyradiotherapy (HRT) in the same doses but in combination with hypoxia (10% oxygen and 90% nitrogen--hypoxic gas mixture HGM-10--group 2) were used in preoperative period. In group 3 HGM-9 (9% oxygen and 91% nitrogen) was used as radioprotector in preoperative period but in increased by 25% radiation doses: total 25 Gy, 5 Gy for 5 days. In the control group only radical surgical treatment was performed. Preoperative irradiation didn't increase the rate of postoperative complications. At the same time the 5-year survival rate was higher in all the groups of patients on combined treatment than in the group of patients on surgical radical treatment. In the group with HGM-9 and increased by 25% radiation doses postoperative complications rate was lower, recurrences and distant metastases occurred less frequently.
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