Navegando por Palavras-chave "radiation"

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    Amfenac increases the radiosensitivity of uveal melanoma cell lines
    (Nature Publishing Group, 2008-05-01) Fernandes, B. F.; Marshall, J-C; Di Cesare, S.; Logan, P.; Maloney, S.; Burnier Júnior, Miguel Noel Nascente [UNIFESP]; McGill Univ; Henry C Witelson Ocular Pathol Lab; Universidade Federal de São Paulo (UNIFESP)
    Purpose To evaluate the proliferation rates of five human uveal melanoma (UM) cell lines after treatment with amfenac, a cyclooxygenase (COX)-2 inhibitor, and subsequent radiation exposure.Methods Five human UM cell lines (92.1, SP6.5, MKT-BR, OCM-1, and UW-1) and one human fibroblast cell line (BJ) were incubated with amfenac. Treated and non-treated cell lines were then exposed to various doses of gamma radiation: 0, 2, 4, 6, and 8 Gy. Sulphorhodamine-B assay was used to assess proliferation rates 48 h post-radiation.Results Treatment of UM cell lines with amfenac prior to radiation led to a marked reduction in proliferation rates. This difference was statistically significant in all cell lines at every radiation dose (P < 0.005), with the exception of 92.1 at 2 Gy (P=0.157). Fibroblasts treated with amfenac showed significantly higher proliferation rates after 2 and 8 Gy, with no significant differences at 0, 4, and 6 Gy.Conclusions the radiosensitivity of UM cell lines was increased by the administration of amfenac, the active metabolite of nepafenac. There appears to be a radioprotective effect of amfenac on human fibroblasts. the topical administration of nepafenac may decrease tumour recurrence and radiation-induced complications while broadening the indications for radiotherapy by treating larger tumours.
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    The effect of imatinib mesylate on the proliferation, invasive ability, and radiosensitivity of retinoblastoma cell lines
    (Nature Publishing Group, 2013-01-01) Moura, L. R. de; Marshall, J-C; Di Cesare, S.; Fernandes, B. F.; Antecka, E.; Burnier, M. N.; McGill Univ; Henry C Witelson Ocular Pathol Lab; Inst Brasileiro Oftalmol; Universidade Federal de São Paulo (UNIFESP)
    Purpose Our aim was to evaluate the potential effect of imatinib mesylate (IM), a small molecule that specifically inhibits the tyrosine quinase receptors, on the proliferation and invasive abilities of two human retinoblastoma (Rb) cell lines. Furthermore, the ability of IM to radiosensitize Rb cells was evaluated. the potential targets of IM (C-kit, PDGRF-alpha and -beta, and c-Abl) were also investigated in these cell lines.Methods Two human Rb cell lines (WERI-RB-1 and Y79) were cultured under normal growth conditions. An MTT-based proliferation assay and a Matrigel invasion assay were performed with and without exposure to 10 mu M of IM. the cells were also irradiated with graded dosages of 0, 2, 4, 6, 8, and 10 Gy with and without IM and their proliferations rates were analyzed. Western blot and immunocytochemical analysis of cytospins were performed to evaluate the expression of C-kit, PDGRF-alpha and -beta, and c-Abl.Results When IM was added to both cell lines a statistically significant (P<0.05) reduction in proliferation and invasive ability were observed. Exposure to IM also significantly increased the radiosensitivity of both Rb cell lines. the c-Abl expression was strongly positive, PDGRF-alpha and -beta expression were also positive but the C-kit expression was negative in both cell lines.Conclusions These results indicate that Gleevec may be useful as an adjuvant treatment in Rb patients, specially those considered for radiation therapy. Eye (2013) 27, 92-99; doi:10.1038/eye.2012.231; published online 16 November 2012
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    Radiação ionizante: o que os olhos não veem, o coração sente
    (Universidade Federal de São Paulo (UNIFESP), 2022) Vincentin Junior, Carlos Antonio [UNIFESP]; Plens, Cláudia Regina [UNIFESP]; http://lattes.cnpq.br/2142424336909827; http://lattes.cnpq.br/3208916221283027; Universidade Federal de São Paulo (UNIFESP)
    Invisible, but as lethal as a projectile expelled by a firearm, ionizing radiation can cause irreversible damage to human beings, generating from a skin lesion to the death of the individual. Many of the effects caused by the interaction of this electromagnetic wave with the body occur late, and treatment to prevent its proliferation in the body is not possible. Countless times these biological damages generate a sudden change in the quality of life of those who interacted with radiation, whether intentionally or not. Despite these facts, there is a way to prevent its fatal effects. It is enough to have security for those who work with this type of energy and also inspections to ensure that accidents do not occur, such as the one in Goiânia with the Cesium element or the Chernobyl nuclear power plant. In other words, respecting the human rights of workers, especially those who work at risk, preserves the most precious asset of human beings: life.
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    THREE-YEAR SAFETY and VISUAL ACUITY RESULTS of EPIMACULAR (90)STRONTIUM/(90)YTTRIUM BRACHYTHERAPY WITH BEVACIZUMAB for the TREATMENT of SUBFOVEAL CHOROIDAL NEOVASCULARIZATION SECONDARY TO AGE-RELATED MACULAR DEGENERATION
    (Lippincott Williams & Wilkins, 2012-01-01) Avila, Marcos P.; Farah, Michael E. [UNIFESP]; Santos, Arturo; Carla, Livia; Fuji, Gildo [UNIFESP]; Rossi, Juliana [UNIFESP]; Nau, Jeffrey; Fed Univ Goiana; Universidade Federal de São Paulo (UNIFESP); Med Ctr Puerta de Hierro; NeoVista Inc
    Purpose: To evaluate the long-term safety and visual acuity outcomes associated with epimacular strontium 90 brachytherapy combined with intravitreal bevacizumab for the treatment of subfoveal choroidal neovascularization because of age-related macular degeneration.Methods: Thirty-four treatment-naive patients with predominantly classic, minimally classic, and occult subfoveal choroidal neovascularization lesions participated in this prospective, 2-year, nonrandomized multicenter study. Subjects from 1 center (n = 19) were reconsented and followed-up for 3 years. Each subject received a single 24-Gy beta irradiation treatment via an intraocular delivery device and 2 planned injections of bevacizumab at treatment and 1 month later. Additional bevacizumab therapy was permitted based on prespecified retreatment criteria. Adverse events were observed, and best-corrected visual acuity was measured using Early Treatment Diabetic Retinopathy Study vision charts. Subjects were evaluated every 3 months during the first year of follow-up and every 6 months during Years 2 and 3 of follow-up.Results: All 34 subjects were followed-up for 24 months and 19 were followed-up through 36 months. With up to 24 months of follow-up, 12 of 24 phakic patients (50%) exhibited >= 2 grades of progression in Lens Opacification Classification System (LOCS) II lens classification; 5 eyes underwent cataract extraction before the Month 36 visit. There was 1 case of nonproliferative retinopathy identified at 36 months of follow-up that did not have an adverse effect on visual acuity, was stable at 43 months of follow-up, and was isolated to the parafoveal region. Mean best-corrected visual acuity demonstrated an average gain of +15.0 and -4.9 letters at 12 months and 24 months, respectively; the drop in mean gain at Month 24 was largely attributable to cataract formation. At 36 months (n = 19), the mean best-corrected visual acuity was +3.9, 90% (17 of 19) of eyes had lost <15 letters from baseline, 53% (10 of 19) had gained >= 1 letter, and 21% (4 of 19) had gained >= 15 letters. Through 36 months, 11 eyes required additional bevacizumab retreatment therapy and received a mean of 3.0 injections (range, 2-7 injections).Conclusion: Epimacular brachytherapy shows promise as a therapeutic option for subfoveal neovascular age-related macular degeneration. the procedure was safe and well tolerated, with a reasonable risk-benefit profile that warrants further study in larger subject populations. the most common adverse event was cataract progression/formation. Surgical complications are similar to those expected from standard vitrectomy trials. This novel device is currently being evaluated in two prospective, randomized, controlled trials in treatment-naive subjects (CABERNET) and in subjects already treated with anti-vascular endothelial growth factor therapy (MERLOT). RETINA 32:10-18, 2012
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    Vascular Therapy for Radiation Cystitis
    (Wiley-Blackwell, 2011-01-01) Soler, Roberto [UNIFESP]; Vianello, Alberto; Fuellhase, Claudius; Wang, Zhan; Atala, Anthony; Soker, Shay; Yoo, James J.; Williams, James Koudy; Wake Forest Univ Hlth Sci; Ludwig Maximilians Univ Munchen; Univ Perugia; Universidade Federal de São Paulo (UNIFESP)
    Purpose: the underlying pathology of radiation cystitis is cellular and vascular damage followed by increased fibrosis and inflammation. This study was to determine if neovascular- promoting therapy could reduce the pathological changes in the bladder wall associated with pelvic irradiation. Methods: Adult female Lewis inbred rats were irradiated with a single dose of 20 Gy directed at their bladder. Four weeks later, 30 rats were divided equally into one of three treatment groups for bladder wall injection of: (1) PBS (Control); (2) PBS containing 50 ng vascular endothelial growth factor (VEGF165); or (3) PBS containing 1 x 10(6) rat endothelial cells (EC). Age- matched non- irradiated rats (n 10) served as untreated controls. At either 1.5 or 3 months following radiation, bladders were analyzed for collagen deposition using Masson's Trichrome staining of collagen and muscle and vascularization using Von Willebrand factor staining of ECs. Quantitative- PCR was used to examine markers of angiogenesis, hypoxia, and fibrosis. Results: the collagen/ muscle ratio was doubled in the control group 3months post- irradiation (P < 0.05 vs. non- irradiated bladders). Both ECs and VEGF inhibited increases in collagen content (P < 0.05 vs. control). Similarly, irradiation reduced bladder wall vessel counts compared to non- irradiated controls (P < 0.05) and both ECs and VEGF maintained vessel counts similar to that of non- irradiated controls (P < 0.05). PCR analysis showed a higher expression of neovascular markers (CD31, KDR) in the EC and VEGF groups compared to non- irradiated controls (P < 0.05). Conclusions: Angiogenesis therapy may be useful in the prevention and/or treatment of the underlying pathology of radiation cystitis. Neurourol. Urodynam. 30: 428- 434, 2011. (C) 2010 Wiley-Liss, Inc.