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Rev. colomb. cardiol ; 27(S1): 72-78, Mar. 2020. graf, ilus
Article in Spanish | LILACS, BNUY, UY-BNMED | ID: biblio-1392339


El número y la complejidad de los procedimientos de diagnóstico e intervencionismo cardiovascular han incrementado de manera significativa, hecho que genera mayor exposición a dosis bajas de radiación ionizante debido a la radiación dispersa por el paciente. El cristalino es una de las estructuras más sensibles a la radiación y las cataratas son la enfermedad ocular más estudiada y frecuente en el personal de la salud ocupacionalmente expuesto a dosis bajas de radiación. La formación de cataratas es un proceso multifactorial y la exposición a la radiación ionizante se ha asociado a opacidades subcapsulares posteriores, que es la forma más común de lesión, seguida por las cataratas corticales. Existen varios estudios que han evaluado los efectos de la exposición ocupacional por radiación ionizante en el cristalino en cardiólogos intervencionistas, comparándolos con controles no expuestos. Concluyen que hay mayor prevalencia de opacidades subcapsulares posteriores en el personal expuesto a radiación ionizante, especialmente en los cardiólogos intervencionistas (por trabajar muy cerca del generador de rayos X), las cuales están relacionadas con la duración de la práctica del intervencionismo cardíaco y disminuyen con el uso regular de los lentes plomados. Lo llamativo de muchos estudios es el bajo uso por parte de los cardiólogos intervencionistas de los elementos de protección radiológica, especialmente gafas y mampara plomada, las cuales han demostrado efectividad en la reducción de la radiación ionizante recibida por el personal de la sala de cateterismo cardiaco.

As the number and complexity of diagnostic and cardiovascular intervention procedures has increased significantly, this has led to a greater exposure to low doses of ionising radiation due to the radiation dispersal by the patient. The crystalline lens is one of the structures most sensitive to radiation, and cataracts are the most studied eye disease, and are common in health staff occupationally exposed to low radiation doses. The formation of cataracts is a process involving many factors, and exposure to ionising radiation has been associated with posterior sub-capsular opacities, the most common form of the injury, followed by cortical cataracts. There are several studies that have evaluated the effects of occupational exposure due to ionising radiation in the crystalline lens in interventionist cardiologists, and comparing them with non-exposed controls. They conclude that there is a higher prevalence of posterior sub-capsular opacities in personnel exposed to ionising radiation, especially in interventionist cardiologists (due to working very near the X-ray generator). These are associated with the duration of the practice of cardiac interventions, and decrease with the regular use of leaded glasses. The low use of radiation protection wear by interventionist cardiologists is highlighted in many studies, especially glasses and a leaded screen, which have shown to be effective in the reduction in the ionising radiation by the staff in the cardiac catheterisation room.

Humans , Radiation, Ionizing , Radiation Protection , Cataract/etiology , Eye Injuries/etiology , Lens, Crystalline/radiation effects , Dose-Response Relationship, Radiation , Occupational Diseases
Article in English | WPRIM | ID: wpr-828974


Objective@#To detect the effects of shortwave radiation on dose-dependent cardiac structure and function in rats after radiation and to elucidate the mechanism of shortwave radiation induced cardiac injury to identify sensitive indicators and prophylactic treatment.@*Methods@#One hundred Wistar rats were either exposed to 27 MHz continuous shortwave at a power density of 5, 10, and 30 mW/cm for 6 min or undergone sham exposure for the control (the rats had to be placed in the exposure system with the same schedules as the exposed animals, but with an inactive antenna). The Ca , glutamic oxaloacetic transaminase (AST), creatine kinase (CK) and lactate dehydrogenase (LDH) content in the peripheral serum of the rats were detected by an automatic blood biochemical analyser. The electrocardiogram (ECG) of standard lead II was recorded by a multi-channel physiological recording and analysis system. The cardiac structure of rats was observed by light and electron microscopy.@*Results@#The results showed that the 5, 10, and 30 mW/cm shortwave radiation caused a significant increased in the levels of Ca , AST, CK, and LDH in the peripheral serum of rats. The cardiac structure was damaged by radiation and showed a disordered arrangement of myocardial fibres, the cavitation and swelling of myocardial mitochondria. These injuries were most significant 7 d after radiation and were not restored until 28 d after radiation.@*Conclusion@#Shortwave radiation of 5, 10, and 30 mW/cm can damage rat cardiac function, including damage to the tissue structure and ultrastructure, especially at the level of the myocardial fibres and mitochondria. Shortwave radiation at 5, 10, and 30 mW/cm induced damage to rat heart function and structure with a dose-effect relationship, i.e., the greater the radiation dose was, the more significant the damage was.

Animals , Dose-Response Relationship, Radiation , Heart , Radiation Effects , Heart Diseases , Ethnology , Pathology , Male , Myocardium , Pathology , Radio Waves , Random Allocation , Rats , Rats, Wistar
Int. braz. j. urol ; 45(6): 1105-1112, Nov.-Dec. 2019. tab, graf
Article in English | LILACS | ID: biblio-1056339


ABSTRACT Purpose: To compare the treatment outcomes of a cohort of prostate cancer patients treated with conventional schedule using IMRT or 3DRT technique. Materials and Methods: Between 2010-2017, 485 men with localized prostate cancer were treated with conventional radiotherapy schedule with a total dose ≥74Gy using IMRT (231) or 3DCRT (254). Late gastrointestinal (GI) and genitourinary (GU) toxicity were retrospectively evaluated according to modified RTOG criteria. The biochemical control was defined by the Phoenix criteria (nadir + 2ng/mL). The comparison between the groups included biochemical recurrence free survival (bRFS), overall survival (OS) and late toxicity. Results: With a median follow-up of 51 months (IMRT=49 and 3DRT=51 months), the maximal late GU for >=grade- 2 during the entire period of follow-up was 13.1% in the IMRT and 15.4% in the 3DRT (p=0.85). The maximal late GI ≥ grade- 2 in the IMRT was 10% and in the 3DRT 24% (p=0.0001). The 5-year bRFS for all risk groups with IMRT and 3D-CRT was 87.5% vs. 87.2% (p=0.415). Considering the risk-groups no significant difference for low-, intermediate- and high-risk groups between IMRT (low-95.3%, intermediate-86.2% and high-73%) and 3D-CRT (low-96.4%, intermediate-88.2% and high-76.6%, p=0.448) was observed. No significant differences for OS and DMFS were observed comparing treatment groups. Conclusion: IMRT reduces significantly the risk of late GI severe complication compared with 3D-CRT using conventional fractionation with a total dose ≥74Gy without any differences for bRFS and OS.

Humans , Male , Aged , Prostatic Neoplasms/radiotherapy , Radiotherapy, Conformal/methods , Radiotherapy, Intensity-Modulated/methods , Prostatic Neoplasms/mortality , Prostatic Neoplasms/pathology , Radiation Injuries , Radiotherapy Dosage , Time Factors , Urogenital System/radiation effects , Retrospective Studies , Risk Factors , Risk Assessment , Disease-Free Survival , Radiotherapy, Conformal/adverse effects , Gastrointestinal Tract/radiation effects , Dose-Response Relationship, Radiation , Radiotherapy, Intensity-Modulated/adverse effects , Kaplan-Meier Estimate , Neoplasm Grading , Middle Aged
Arq. neuropsiquiatr ; 77(4): 232-238, Apr. 2019. tab, graf
Article in English | LILACS | ID: biblio-1001356


ABSTRACT Gamma Knife® radiosurgery (GKRS) for trigeminal neuralgia is an effective treatment with at least a 50% reduction of pain in 75-95% of patients. Objective: To present the first series of patients treated for trigeminal neuralgia using GKRS in Latin America. Methods: Retrospective analysis. Analysis consisted of time to improvement of symptoms, best Barrow Neurological Institute scale (BNI) score after procedure, time without pain, time to recurrence and post-procedural hypoesthesia. Results: Nineteen cases of classical trigeminal neuralgia were analyzed and three cases of symptomatic trigeminal neuralgia were described. Mean time from symptom onset to radiosurgery was 99.6 months, and 78.9% of patients had undergone invasive procedures before treatment. Patients were followed for a mean of 21.7 months. BNI I was achieved in 36.8%, IIIa in 21.1%, IIIb in 21.1%, IV in 5.3% and V in 15.7%. New hypoesthesia developed in 12.1% patients, which was associated with achieving BNI I after the procedure (p < 0.05). Time from diagnosis to GKRS was higher in patients who failed to achieve BNI I (143 vs. 76 months). The distance from the root entry zone in patients who achieved BNI I was greater than patients who did not (1.94 vs. 1.14 mm). Mean distance from the root entry zone in patients with new hypoesthesia was 2.85 mm vs. 1.06 mm (p = 0.06). Conclusion: Clinical response to GKRS is related to the time between diagnosis and procedure, thus its indication should be considered early in the management of these patients.

RESUMO A radiocirurgia por Gamma Knife (GKRS) para neuralgia do trigêmeo é um tratamento comprovado, com redução de pelo menos 50% da dor em 75-95% dos casos. Objetivo: Apresentar a primeira série de pacientes tratados por neuralgia do trigêmeo com GKRS na America Latina. Métodos: Análise retrospectiva. A análise consistiu no tempo até melhora do sintoma, melhor escala do Barrow Neurological Institute (BNI) depois do procedimento, tempo sem dor, tempo até recorrência e hipoestesia pós-procedimento. Resultados: Dezenove casos de neuralgia do trigêmeo clássica foram analisados e três casos de neuralgia do trigêmeo sintomática foram descritos. Tempo médio entre começo dos sintomas e GKRS foi de 99,6 meses e 78,9% dos pacientes já tinham sido submetidos a procedimento invasivo prévio. O tempo de acompanhamento médio foi de 21,7 meses. BNI I foi conseguido em 36,8%, IIIa em 21,1%, IIIb em 21,1%, IV em 5,3% e V em 15,7%. Nova hipoestesia apareceu em 12,1% dos casos, o que foi associado a conseguir BNI I pós-procedimento (p < 0,05). Tempo desde o diagnóstico até GKRS foi maior em pacientes que não conseguiram BNI I (143 vs. 76 meses). Distância da zona de entrada do nervo em pacientes que conseguiram BNI I foi maior (1,94 vs. 1,14mm). Distância do zona de entrada do nervo em pacientes com nova hipoestesia foi de 2,85mm vs. 1,06mm (p = 0,06) Conclusão: A resposta à GKRS está relacionada ao tempo entre diagnóstico e procedimento, pelo que a indicação de GKRS deve ser considerada cedo no tratamento desses pacientes.

Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Trigeminal Neuralgia/radiotherapy , Radiosurgery/methods , Recurrence , Time Factors , Pain Measurement , Reproducibility of Results , Retrospective Studies , Follow-Up Studies , Treatment Outcome , Rhizotomy/methods , Dose-Response Relationship, Radiation , Latin America
Arq. bras. oftalmol ; 82(1): 38-44, Jan.-Feb. 2019. tab, graf
Article in English | LILACS | ID: biblio-973869


ABSTRACT Purpose: To evaluate the effects of ranibizumab and amfenac in human uveal melanoma cell lines and to explore the ability of these compounds to sensitize uveal melanoma cells to radiation therapy. Methods: The 92.1 human uveal melanoma cell line was cultured and subjected to the proposed treatment (ranibizumab, amfenac, and a combination of both). Proliferation, migration, and invasion assays of the 92.1 uveal melanoma cell line were assessed after pretreatment with ranibizumab (125 mg/mL), amfenac (150 nM), or a combination of both. In addition, proliferation rates were assessed after treatment with ranibizumab and amfenac, and the cells were subsequently exposed to various radiation doses (0, 4, and 8 Gy). Results: Proliferation assay: cells treated with a combination of ranibizumab and amfenac had lower proliferation rates than controls (p=0.016) and than those treated with only ranibizumab (p=0.033). Migration assay: a significantly lower migration rate was observed in cells treated with amfenac than the control (p=0.014) and than those treated with ranibizumab (p=0.044). Invasion assay: there were no significant differences among the studied groups. Irradiation exposure: in the 4 Gy dose group, there were no significant differences among any groups. In the 8 Gy dose group, treatment with ranibizumab, amfenac, and their combination prior to application of the 8 Gy radiation led to a marked reduction in proliferation rates (p=0.009, p=0.01, and p=0.034, respectively) compared with controls. Conclusion: Combination of ranibizumab and amfenac reduced the proliferation rate of uveal melanoma cells; however, only amfenac monotherapy significantly decreased cell migration. The radiosensitivity of the 92.1 uveal melanoma cell line increased following the administration of ranibizumab, amfenac, and their combination. Further investigation is warranted to determine if this is a viable pretreatment strategy to render large tumors amenable to radiotherapy.

RESUMO Objetivo: Avaliar os efeitos do ranibizumabe em associação com o amfenac nas células de melanoma uveal humano e explorar a capacidade desses compostos em sensibilizar as células de melanoma uveal à radioterapia. Métodos: Células de melanoma uveal humano do tipo 92.1 foram cultivadas e submetidas ao tratamento proposto (ranibizumabe, amfenac e a combinação de ambos). Ensaios de proliferação, migração e invasão com as células de melanoma uveal do tipo 92.1 foram avaliados após tratamento com ranibizumabe (125 mg/ml), amfenac (150 nM) e a combinação de ambos. Além disso, as taxas de proliferação foram avaliadas após tratamento com ranibizumabe e amfenac com subsequente exposição das células a diferentes doses de radiação (0 Gy, 4 Gy e 8 Gy). Resultados: Ensaio de proliferação: células tratadas com ranibizumabe e amfenac combinados apresentaram taxas de proliferação inferiores em comparação ao grupo controle (p=0,016), do que as tratadas apenas com ranibizumabe (p=0,033). Ensaio de migração: foi observada uma taxa de migração significativamente mais baixa nas células tratadas com amfenac do que no grupo controle (p=0,014) e do que nas tratadas com ranibizumabe (p=0,044). Ensaio de invasão: não houve diferenças significativas entre os grupos estudados. Exposição à irradiação: no grupo da dose de 4 Gy, não houve diferença significante entre os grupos. No grupo da dose de 8 Gy, o tratamento com ranibizumabe, afenac e sua combinação antes da aplicação da radiação de 8 Gy levou a uma redução acentuada nas taxas de proliferação (p=0,009, p=0,01 e p=0,034, respectivamente) em comparação aos grupos controle. Conclusão: A combinação de ranibizumabe e amfenac reduziu a taxa de proliferação das células de melanoma uveal; no entanto, apenas o amfenac diminuiu significativamente a migração celular. A radiossensibilidade das células de melanoma uveal do tipo 92.1 aumentou após a administração de ranibizumabe, amfenac e sua combinação. Mais investigações são necessárias para determinar se esta é uma estratégia de pré-tratamento viável para tornar grandes tumores passíveis de radioterapia.

Humans , Phenylacetates/pharmacology , Angiogenesis Inhibitors/pharmacology , Cyclooxygenase 2 Inhibitors/pharmacology , Ranibizumab/pharmacology , Melanoma/drug therapy , Melanoma/radiotherapy , Radiation Tolerance , Uveal Neoplasms/drug therapy , Uveal Neoplasms/radiotherapy , Antineoplastic Combined Chemotherapy Protocols , Cell Movement/drug effects , Cell Movement/radiation effects , Reproducibility of Results , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/radiation effects , Dose-Response Relationship, Radiation
Acta cir. bras ; 34(2): e201900210, 2019. tab, graf
Article in English | LILACS | ID: biblio-989058


Abstract Purpose: To analyze aspects of the biomodulating effect of light in biological tissues, bone cells from surgical explants of the femur of rats were irradiated with low intensity laser. Methods: Bone cells were cultured and irradiated with LASER light (GaAlAs). Growth, cell viability, mineralized matrix formation, total protein dosage, immunostimulatory properties, cytochemical analysis, gene expression of bone proteins were examined using live cell imaging and cell counting by colorimetric assay. The gene expression of: alkaline phosphatase (ALP), type 1 collagen, osteocalcin and osteopontin through the real-time polymerase chain reaction. Results: At 8 days, the viability of the irradiated culture was 82.3% and 72.4% in non-irradiated cells. At 18 days, the cellular viability (with laser) was 77.42% and 47.62% without laser. At 8 days, the total protein concentration was 21.622 mg / mol in the irradiated group and 16, 604 mg / mol in the non-irradiated group and at 18 days the concentration was 37.25 mg / mol in the irradiated group and 24, 95 mg / mol in the non-irradiated group. Conclusion: The laser interfered in the histochemical reaction, cell viability, matrix mineralization, and maintained the cellular expression of proteins

Animals , Rats , Osteoblasts/radiation effects , Cell Differentiation/radiation effects , Cell Survival/radiation effects , Low-Level Light Therapy/methods , Time Factors , Cells, Cultured , Rats, Wistar , Dose-Response Relationship, Radiation
Article in English | WPRIM | ID: wpr-773418


OBJECTIVE@#To estimate the detrimental effects of shortwave exposure on rat hippocampal structure and function and explore the underlying mechanisms.@*METHODS@#One hundred Wistar rats were randomly divided into four groups (25 rats per group) and exposed to 27 MHz continuous shortwave at a power density of 5, 10, or 30 mW/cm2 for 6 min once only or underwent sham exposure for the control. The spatial learning and memory, electroencephalogram (EEG), hippocampal structure and Nissl bodies were analysed. Furthermore, the expressions of N-methyl-D-aspartate receptor (NMDAR) subunits (NR1, NR2A, and NR2B), cAMP responsive element-binding protein (CREB) and phosphorylated CREB (p-CREB) in hippocampal tissue were analysed on 1, 7, and 14 days after exposure.@*RESULTS@#The rats in the 10 and 30 mW/cm2 groups had poor learning and memory, disrupted EEG oscillations, and injured hippocampal structures, including hippocampal neurons degeneration, mitochondria cavitation and blood capillaries swelling. The Nissl body content was also reduced in the exposure groups. Moreover, the hippocampal tissue in the 30 mW/cm2 group had increased expressions of NR2A and NR2B and decreased levels of CREB and p-CREB.@*CONCLUSION@#Shortwave exposure (27 MHz, with an average power density of 10 and 30 mW/cm2) impaired rats' spatial learning and memory and caused a series of dose-dependent pathophysiological changes. Moreover, NMDAR-related CREB pathway suppression might be involved in shortwave-induced structural and functional impairments in the rat hippocampus.

Animals , Cyclic AMP Response Element-Binding Protein , Genetics , Metabolism , Dose-Response Relationship, Radiation , Electroencephalography , Radiation Effects , Hippocampus , Radiation Effects , Male , Memory , Radiation Effects , Nissl Bodies , Physiology , Radiation Effects , Radio Waves , Random Allocation , Rats , Rats, Wistar , Receptors, N-Methyl-D-Aspartate , Genetics , Metabolism , Spatial Learning , Radiation Effects
J. bras. pneumol ; 44(6): 469-476, Nov.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-984609


ABSTRACT Objective: To evaluate the impact of thoracic radiotherapy on respiratory function and exercise capacity in patients with breast cancer. Methods: Breast cancer patients in whom thoracic radiotherapy was indicated after surgical treatment and chemotherapy were submitted to HRCT, respiratory evaluation, and exercise capacity evaluation before radiotherapy and at three months after treatment completion. Respiratory muscle strength testing, measurement of chest wall mobility, and complete pulmonary function testing were performed for respiratory evaluation; cardiopulmonary exercise testing was performed to evaluate exercise capacity. The total radiotherapy dose was 50.4 Gy (1.8 Gy/fraction) to the breast or chest wall, including supraclavicular lymph nodes (SCLN) or not. Dose-volume histograms were calculated for each patient with special attention to the ipsilateral lung volume receiving 25 Gy (V25), in absolute and relative values, and mean lung dose. Results: The study comprised 37 patients. After radiotherapy, significant decreases were observed in respiratory muscle strength, chest wall mobility, exercise capacity, and pulmonary function test results (p < 0.05). DLCO was unchanged. HRCT showed changes related to radiotherapy in 87% of the patients, which was more evident in the patients submitted to SCLN irradiation. V25% significantly correlated with radiation pneumonitis. Conclusions: In our sample of patients with breast cancer, thoracic radiotherapy seemed to have caused significant losses in respiratory and exercise capacity, probably due to chest wall restriction; SCLN irradiation represented an additional risk factor for the development of radiation pneumonitis.

RESUMO Objetivo: Avaliar o impacto da radioterapia torácica na função respiratória e capacidade de exercício em pacientes com câncer de mama. Métodos: Pacientes com câncer de mama com indicação de radioterapia torácica após tratamento cirúrgico e quimioterápico foram submetidas a TCAR, avaliação respiratória e avaliação da capacidade de exercício antes da radioterapia torácica e três meses após o término do tratamento. Foram realizados teste de força muscular respiratória, medição da mobilidade torácica e prova de função pulmonar completa para a avaliação respiratória; realizou-se teste de exercício cardiopulmonar para avaliar a capacidade de exercício. A dose total de radioterapia foi de 50,4 Gy (1,8 Gy/fração) na mama ou na parede torácica, incluindo ou não a fossa supraclavicular (FSC). Histogramas dose-volume foram calculados para cada paciente com especial atenção para o volume pulmonar ipsilateral que recebeu 25 Gy (V25), em números absolutos e relativos, e a dose pulmonar média. Resultados: O estudo incluiu 37 pacientes. Após a radioterapia, observou-se diminuição significativa da força muscular respiratória, mobilidade torácica, capacidade de exercício e resultados da prova de função pulmonar (p < 0,05). A DLCO permaneceu inalterada. A TCAR mostrou alterações relacionadas à radioterapia em 87% das pacientes, o que foi mais evidente nas pacientes submetidas à irradiação da FSC. O V25% correlacionou-se significativamente com a pneumonite por radiação. Conclusões: Em nossa amostra de pacientes com câncer de mama, a radioterapia torácica parece ter causado perdas significativas na capacidade respiratória e de exercício, provavelmente por causa da restrição torácica; a irradiação da FSC representou um fator de risco adicional para o desenvolvimento de pneumonite por radiação.

Humans , Female , Middle Aged , Breast Neoplasms/radiotherapy , Forced Expiratory Volume/radiation effects , Exercise Tolerance/radiation effects , Radiation Pneumonitis/diagnostic imaging , Respiratory Muscles/radiation effects , Respiratory Muscles/physiopathology , Lymphatic Irradiation/adverse effects , Tomography, X-Ray Computed/methods , Prospective Studies , Dose-Response Relationship, Radiation
An. bras. dermatol ; 93(2): 238-241, Mar.-Apr. 2018. tab, graf
Article in English | LILACS | ID: biblio-887175


Abstract: Background: Topical agents used in combination with phototherapy or photochemotherapy may have both blocking or enhancing effects in ultraviolet rays. Objective: In this in vivo study, the effects of topical petrolatum, basis cream, glycerine, and olive oil on the transmission of ultraviolet A radiation were investigated. Methods: A test was performed to determine the minimal phototoxic dose on 29 volunteers with only psoralen plus ultraviolet A (PUVA) and then the same test was repeated with white petrolatum, basis cream, glycerine, olive oil, and sunscreen (0.3cc/25cm2). The effects of each agent on the minimal phototoxic dose were determined after 72 h. Results: When compared to pure PUVA, there was a statistically significant increase in the mean minimal phototoxic dose values by the application of white petrolatum (P = 0.011), but there was no significant increase or decrease in the mean minimal phototoxic dose values after the application of basis cream (P = 0.326), glycerine (P = 0.611) or olive oil (P = 0.799). Study limitations: Low number of patients Conclusion: The application of white petrolatum, which has a blocking effect, and also of basis cream immediately before PUVA therapy should not be recommended. Although we specify that glycerine and maybe olive oil can be used before photochemotherapy, there is a need for further research in larger series.

Humans , Petrolatum/pharmacology , Photochemotherapy/methods , PUVA Therapy/methods , Skin Diseases/drug therapy , Ultraviolet Rays , Photosensitizing Agents/pharmacology , Emollients/pharmacology , Sunscreening Agents/pharmacology , Time Factors , Skin Tests , Single-Blind Method , Reproducibility of Results , Treatment Outcome , Dermatitis, Phototoxic/prevention & control , Statistics, Nonparametric , Dose-Response Relationship, Radiation , Olive Oil/pharmacology , Glycerol/pharmacology
Clinics ; 73(supl.1): e557s, 2018. tab, graf
Article in English | LILACS | ID: biblio-974950


Technological developments have allowed improvements in radiotherapy delivery, with higher precision and better sparing of normal tissue. For many years, it has been well known that ionizing radiation has not only local action but also systemic effects by triggering many molecular signaling pathways. There is still a lack of knowledge of this issue. This review focuses on the current literature about the effects of ionizing radiation on the immune system, either suppressing or stimulating the host reactions against the tumor, and the factors that interact with these responses, such as the radiation dose and dose / fraction effects in the tumor microenvironment and vasculature. In addition, some implications of these effects in cancer treatment, mainly in combined strategies, are addressed from the perspective of their interactions with the more advanced technology currently available, such as heavy ion therapy and nanotechnology.

Humans , Radiation, Ionizing , Radiotherapy/adverse effects , Immune System/radiation effects , Neoplasms/immunology , Neoplasms/radiotherapy , Radiotherapy/trends , Cell Death/radiation effects , Apoptosis/radiation effects , Apoptosis/immunology , Dose-Response Relationship, Radiation , Immunotherapy/methods , Immunotherapy/trends , Necrosis/etiology
J. appl. oral sci ; 26: e20170172, 2018. tab, graf
Article in English | LILACS, BBO | ID: biblio-893733


Abstract Background: Osteoradionecrosis of the jaw (ORNJ) is the most severe and complex sequel of head and neck radiotherapy (RT) because of the bone involved, it may cause pain, paresthesia, foul odor, fistulae with suppuration, need for extra oral communication and pathological fracture. We treated twenty lesions of ORNJ using low-level laser therapy (LLLT) and antimicrobial photodynamic therapy (aPDT). The objective of this study was to stimulate the affected area to homeostasis and to promote the healing of the oral mucosa. Methods: We performed aPDT on the exposed bone, while LLLT was performed around the bone exposure (red spectrum) and on the affected jaw (infrared spectrum). Monitoring and clinical intervention occurred weekly or biweekly for 2 years. Results: 100% of the sample presented clinical improvement, and 80% presented complete covering of the bone exposure by intact oral mucosa. Conclusion: LLLT and aPDT showed positive results as an adjuvant therapy to treat ORNJ.

Humans , Male , Female , Adult , Aged , Osteoradionecrosis/therapy , Photochemotherapy/methods , Jaw Diseases , Low-Level Light Therapy/methods , Chemoradiotherapy, Adjuvant/methods , Anti-Infective Agents/therapeutic use , Osteoradionecrosis/pathology , Time Factors , Wound Healing/radiation effects , Jaw Diseases/pathology , Prospective Studies , Reproducibility of Results , Treatment Outcome , Dose-Response Relationship, Radiation , Homeostasis/drug effects , Homeostasis/radiation effects , Middle Aged , Mouth Mucosa/drug effects , Mouth Mucosa/radiation effects
Braz. j. med. biol. res ; 51(9): e7404, 2018. graf
Article in English | LILACS | ID: biblio-951760


DNA repair pathways, cell cycle checkpoints, and redox protection systems are essential factors for securing genomic stability. The aim of the present study was to analyze the effect of Ilex paraguariensis (Ip) infusion and one of its polyphenolic components rutin on cellular and molecular damage induced by ionizing radiation. Ip is a beverage drank by most inhabitants of Argentina, Paraguay, Southern Brazil, and Uruguay. The yeast Saccharomyces cerevisiae (SC7Klys 2-3) was used as the eukaryotic model. Exponentially growing cells were exposed to gamma rays (γ) in the presence or absence of Ip or rutin. The concentrations used simulated those found in the habitual infusion. Surviving fractions, mutation frequency, and DNA double-strand breaks (DSB) were determined after treatments. A significant increase in surviving fractions after gamma irradiation was observed following combined exposure to γ+R, or γ+Ip. Upon these concomitant treatments, mutation and DSB frequency decreased significantly. In the mutant strain deficient in MEC1, a significant increase in γ sensitivity and a low effect of rutin on γ-induced chromosomal fragmentation was observed. Results were interpreted in the framework of a model of interaction between radiation-induced free radicals, DNA repair pathways, and checkpoint controls, where the DNA damage that induced activation of MEC1 nodal point of the network could be modulated by Ip components including rutin. Furthermore, ionizing radiation-induced redox cascades can be interrupted by rutin potential and other protectors contained in Ip.

Rutin/pharmacology , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/radiation effects , Plant Extracts/pharmacology , Antimutagenic Agents/pharmacology , Ilex paraguariensis/chemistry , Radiation Protection/methods , Mass Spectrometry , DNA, Fungal/radiation effects , Cell Survival/drug effects , Cell Survival/radiation effects , Cells, Cultured , Reproducibility of Results , Chromatography, Liquid , Mutagenesis , DNA Repair , Dose-Response Relationship, Radiation , DNA Breaks, Double-Stranded , Mutation Rate , Gamma Rays
An. acad. bras. ciênc ; 89(3): 1925-1933, July-Sept. 2017. graf
Article in English | LILACS | ID: biblio-886733


ABSTRACT This study aimed to evaluate the radiosensitivity of castor bean seeds after applications of different doses of Cobalt60 gamma radiation. Seeds were pre-soaked for 24 hours in distilled water and then irradiated with 50, 100, 150, and 200 Gy, except the control. Sowing was performed in trays, which contained soil as substrate and were maintained in a greenhouse. The electrical conductivity, emergence, emergence speed index, growth parameters and activities of antioxidant enzymes (superoxide dismutase, ascorbate peroxidase, and catalase) were evaluated in the leaves and roots of castor bean seedlings. Gamma radiation did not affect the electrical conductivity of the seeds; however, at a dose of 200 Gy, the emergence and emergence speed index of the seedlings was negatively affected. An analysis of the morphophysiological parameters revealed a reduction in seedling size as the radiation dose increased. There was a significant increase in superoxide dismutase and ascorbate peroxidase activities at higher radiation doses in the leaves, but not in roots. Thus, the analysis of all the variables suggests a response pattern as to the morphophysiological and biochemical changes of castor bean seedlings due to the increase of gamma radiation, which may serve as a tool for generating greater genetic variability.

Ricinus/radiation effects , Seeds/radiation effects , Cobalt Radioisotopes , Germination/radiation effects , Gamma Rays , Ricinus/growth & development , Seeds/growth & development , Dose-Response Relationship, Radiation
An. acad. bras. ciênc ; 89(1,supl): 649-659, May. 2017. graf
Article in English | LILACS | ID: biblio-886652


ABSTRACT Several molecules and events involved in cell response to radiation-induced damage have been investigated towards a personalized radiotherapy. Considering the importance of active caspase-3 in the proteolytic cascade that ensures radiation-induced apoptosis execution, this research was designed to evaluate the expression levels of this protein as a bioindicator of individual radiosensitivity. Peripheral blood samples of 10 healthy individuals were gamma-irradiated (cobalt-60 source) with 1, 2 and 4 Gy (control: non-irradiated samples), and active caspase-3 expression levels were measured in lymphocytes, by flow cytometry, ex vivo and after different times of in vitro incubation (24, 48 and 72 hours). Short-term incubation of 24 h was the most adequate condition to evidence correlations between dose radiation and active caspase-3 expression. For each radiation dose, it was observed a significant inter-individual variation in active caspase-3 expression intensity, suggesting that this parameter may be suitable for evidence individual radiosensitivity. The methodology presented and discussed in this work may help to predict healthy tissues response to radiation exposure toward the better patient outcome.

Humans , Male , Female , Adult , Radiation Tolerance/radiation effects , Lymphocytes/radiation effects , Cobalt Radioisotopes , Apoptosis/radiation effects , Caspase 3/metabolism , Lymphocytes/enzymology , Environmental Biomarkers , Dose-Response Relationship, Radiation , Flow Cytometry
Acta cir. bras ; 32(4): 319-324, Apr. 2017. graf
Article in English | LILACS | ID: biblio-837703


Abstract Purpose: To describe a new model of actinic enteritis that does not use radiotherapy machines. Methods: Sixteen Wistar rats were divided into four groups, consisting of four animals each: control (group A), two weeks after irradiation (group B), five weeks after irradiation (group C) and eight weeks after irradiation (group D). Animals were given a 10Gy radiation from a Cobalt-60 natural source in a nuclear technology research center. Protections of the surrounding tissues were obtained through the usage of plumb devices with a hole in the center, which served as a collimator. We obtained irradiated and non-irradiated colons from each animal. Results: In group B we found an important inflammatory response in the irradiated colon, which appeared in a reduced way in group C and was minimal in group D, in which we found a relevant collagen submucosal deposition/fibrosis. In all groups, the non-irradiated colon had a lower pathological damage in comparison with the irradiated colon. Conclusion: We thus described an efficient and feasible technique for obtaining an animal model of actinic enteritis.

Animals , Female , Rats , Radiation Injuries, Experimental/pathology , Cobalt Radioisotopes , Colon/radiation effects , Dose-Response Relationship, Radiation , Rats, Wistar , Colon/pathology , Disease Models, Animal
Int. braz. j. urol ; 43(2): 216-223, Mar.-Apr. 2017. tab, graf
Article in English | LILACS | ID: biblio-840817


ABSTRACT Introduction There is a growing interest in achieving higher survival rates with the lowest morbidity in localized prostate cancer (PC) treatment. Consequently, minimally invasive techniques such as low-dose rate brachytherapy (BT) and robotic-assisted prostatectomy (RALP) have been developed and improved. Comparative analysis of functional outcomes and quality of life in a prospective series of 51BT and 42Da Vinci prostatectomies DV Materials and Methods Comparative analysis of functional outcomes and quality of life in a prospective series of 93 patients with low-risk localized PC diagnosed in 2011. 51patients underwent low-dose rate BT and the other 42 patients RALP. IIEF to assess erectile function, ICIQ to evaluate continence and SF36 test to quality of life wee employed. Results ICIQ at the first revision shows significant differences which favour the BT group, 79% present with continence or mild incontinence, whereas in the DV group 45% show these positive results. Differences disappear after 6 months, with 45 patients (89%) presenting with continence or mild incontinence in the BT group vs. 30 (71%) in the DV group. 65% of patients are potent in the first revision following BT and 39% following DV. Such differences are not significant and cannot be observed after 6 months. No significant differences were found in the comparative analysis of quality of life. Conclusions ICIQ after surgery shows significant differences in favour of BT, which disappear after 6 months. Both procedures have a serious impact on erectile function, being even greater in the DV group. Differences between groups disappear after 6 months.

Humans , Male , Prostatectomy/methods , Prostatic Neoplasms/surgery , Prostatic Neoplasms/radiotherapy , Quality of Life , Brachytherapy/methods , Robotic Surgical Procedures/methods , Postoperative Complications , Prostatectomy/adverse effects , Time Factors , Urinary Incontinence/etiology , Severity of Illness Index , Brachytherapy/adverse effects , Prospective Studies , Surveys and Questionnaires , Treatment Outcome , Dose-Response Relationship, Radiation , Robotic Surgical Procedures/adverse effects , Erectile Dysfunction/etiology , Middle Aged
An. bras. dermatol ; 92(1): 142-144, Jan.-Feb. 2017. graf
Article in English | LILACS | ID: biblio-1038244


ABSTRACT Daylight photodynamic therapy has been used in countries with high latitudes during the summer for actinic keratoses treatment with reports of similar efficacy to conventional photodynamic therapy. We evaluate its safety in 20 patients in the city of Fortaleza, a local with low latitude and high brightness. Sixteen patients did not report any discomfort due to the procedure. Daylight photodynamic therapy is an easy application method with great tolerability by the patient and has the possibility of being performed throughout the year in these regions. It can mean a promising tool in the control of skin cancer.

Humans , Photochemotherapy/methods , Scalp Dermatoses/drug therapy , Sunlight , Facial Dermatoses/drug therapy , Keratosis, Actinic/drug therapy , Time Factors , Treatment Outcome , Photosensitizing Agents/therapeutic use , Dose-Response Relationship, Radiation , Aminolevulinic Acid/analogs & derivatives , Aminolevulinic Acid/therapeutic use
GJO-Gulf Journal of Oncology [The]. 2017; (24): 24-29
in English | IMEMR | ID: emr-187529


Aim of the study: To investigate the effects of dose-volume parameters of brain parenchyma, optic nerves [ONs] and cribriform plate [CP], which were determined on central nervous system [CMS] control in pediatric leukemia patients who have undergone prophylactic cranial irradiation [PCI] at our department

Patients and Methods: In the current study, the records of 14 patients were examined retrospectively. Along with the minimum and maximum doses for brain and CP, D95% [minimal dose received by the 95% volume of a structure] and V95% [percent volume of target receiving 95% of prescribed dose] could be obtained from the dose-volume histogram. Statistical analyses were conducted using the Mann Whitney test in SPSS-15

Results: ALL/AMI ratio was 9/5. CMS relapse was observed only in 2 patients. The minimum dose was 1249 [1100-1782] cGy, 1036 [547-1651] cGy, 856 [308-1460] cGy and 1234 [922-1727] cGy for brain parenchyma, right ON, left ON and CP, respectively. The value of D95%/D was 1,01 [1-1.06] and 0.99 [0.92-1.06] for brain parenchyma and CP, respectively. V95% was 99.8% [98.6%-100%] and 98.1% [80.5%-100%] for brain parenchyma and CP, respectively. The analyses revealed that none of the target tissue dose-volume parameters for PCI affected CNS relapse [p>0.05]

Conclusion: In our study; it was found that the dose-volume parameters of the brain, CP and ONs did not have any effect on CNS relapse. Along with the other clinical factors, the scarce number of patients included in the study might have concealed the effects of parameters related to RT.

Child , Female , Humans , Male , Treatment Outcome , Radiotherapy Planning, Computer-Assisted , Dose-Response Relationship, Radiation , Leukemia/radiotherapy , Child , Retrospective Studies
Braz. oral res. (Online) ; 31: e7, 2017. tab, graf
Article in English | LILACS | ID: biblio-839537


Abstract The aim of this study was to evaluate the efficacy of low-level 940 nm laser therapy with energy intensities of 5, 10 and 20 J/cm2 on bone healing in an animal model. A total of 48 female adult Wistar rats underwent surgery to create bone defects in the right tibias. Low-level laser therapy (LLLT) was applied immediately after surgery and on post-operative days 2, 4, 6, 8, 10 and 12 in three study groups with energy intensities of 5 J/cm2, 10 J/cm2 and 20 J/cm2 using a 940 nm Gallium-Aluminium-Arsenide (Ga-Al-As) laser, while one control group underwent only the tibia defect surgery. All animals were sacrificed 4 or 8 weeks post-surgery. Fibroblasts, osteoblasts, osteocytes, osteoclasts and newly formed vessels were evaluated by a histological examination. No significant change was observed in the number of osteocytes, osteoblasts, osteoclasts and newly formed vessels at either time period across all laser groups. Although LLLT with the 10 J/cm2 energy density increased fibroblast activity at the 4th week in comparison with the 5 and 20 J/cm2 groups, no significant change was observed between the laser groups and the control group. These results indicate that low-level 940 nm laser with different energy intensities may not have marked effects on the bone healing process in both phases of bone formation.

Animals , Female , Wound Healing/radiation effects , Bone Regeneration/radiation effects , Low-Level Light Therapy/methods , Lasers, Semiconductor/therapeutic use , Osteoblasts/radiation effects , Osteoclasts/radiation effects , Osteogenesis/radiation effects , Reference Values , Tibia/radiation effects , Tibia/pathology , Time Factors , Reproducibility of Results , Treatment Outcome , Rats, Wistar , Dose-Response Relationship, Radiation , Fibroblasts/radiation effects
Article in English | WPRIM | ID: wpr-167301


PURPOSE: The correlation between radiation dose and loco-regional control (LRC) was evaluated in patients with stage II-III esophageal cancer treated with definitive concurrent chemoradiotherapy (CRT). MATERIALS AND METHODS: Medical records of 236 stage II-III esophageal cancer patients treated with definitive CRT at Yonsei Cancer Center between 1994 and 2013 were retrospectively reviewed. Among these, 120 received a radiation dose of 60 Gy) is associated with increased LRC, PFS, and OS in patients with stage II-III esophageal cancer treated with definitive CRT.

Chemoradiotherapy , Disease-Free Survival , Dose-Response Relationship, Radiation , Drug Therapy , Esophageal Neoplasms , Humans , Karnofsky Performance Status , Medical Records , Retrospective Studies