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2.
Tumori ; 103(5): 438-442, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26350182

RESUMO

AIMS: The purpose of this study is to calculate the treatment plans and to compare the dose distributions and dose-volume histograms (DVH) for 6 external radiotherapy techniques for the treatment of retinoblastoma as well as intensity-modulated radiotherapy (IMRT) and fractionated stereotactic radiotherapy (Cyberknife). METHODS: Treatment plans were developed using 6 techniques, including an en face electron technique (ET), an anterior and lateral wedge photon technique (LFT), a 3D conformal (6 fields) technique (CRT), an inverse plan IMRT, tomotherapy, and conventional focal stereotactic external beam radiotherapy with Cyberknife (SBRT). Dose volume analyses were carried out for each technique. RESULTS: All techniques except electron provided similar target coverage. When comparing conformal plan with IMRT and SBRT, there was no significant difference in planning target volume dose distribution. The mean volume of ipsilateral bony orbit received more than 20 Gy, a suggested threshold for bone growth inhibition. The V20 Gy was 73% for the ET, 57% for the LFT, 87% for the CRT, 65% for the IMRT, 66% for the tomotherapy, and 2.7% for the SBRT. CONCLUSIONS: This work supports the potential use of IMRT and SBRT to spare normal tissues in these patients.


Assuntos
Radiocirurgia , Radioterapia de Intensidade Modulada , Retinoblastoma/radioterapia , Retinoblastoma/cirurgia , Humanos , Lesões por Radiação , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Retinoblastoma/patologia
3.
Turk J Haematol ; 33(3): 248-50, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27093891

RESUMO

Tumor lysis syndrome (TLS) is an important oncological emergency that is usually observed with hematological malignancies and rarely with solid tumors. It can be induced either by therapy or spontaneously. Radiotherapy-induced TLS has been rarely reported in the literature. Here we present a patient with a diagnosis of metastatic prostate cancer and chronic lymphocytic leukemia complicated with TLS during palliative radiotherapy.


Assuntos
Leucemia Linfocítica Crônica de Células B/terapia , Síndrome de Lise Tumoral/terapia , Irradiação Corporal Total/efeitos adversos , Idoso , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Masculino , Síndrome de Lise Tumoral/diagnóstico
4.
Asian Pac J Cancer Prev ; 15(17): 7371-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25227844

RESUMO

BACKGROUND: Concurrent chemo-radiotherapy is the recommended standard treatment modality for patients with locally advanced lung cancer. The purpose of three-dimensional conformal radiotherapy (3DCRT) is to minimize normal tissue damage while a high dose can be delivered to the tumor. The most common dose limiting side effect of thoracic RT is radiation pneumonia (RP). In this study we evaluated the relationship between dose-volume histogram parameters and radiation pneumonitis. This study targeted prediction of the possible development of RP and evaluation of the relationship between dose-volume histogram (DVH) parameters and RP in patients undergoing 3DCRT. MATERIALS AND METHODS: DVHs of 41 lung cancer patients treated with 3DCRT were evaluated with respect to the development of grade ≥ 2 RP by excluding gross tumor volume (GTV) and planned target volume (PTV) from total (TL) and ipsilateral (IPSI) lung volume. RESULTS: Were admitted statistically significant for p<0.05. CONCLUSIONS: The cut-off values for V5, V13, V20, V30, V45 and the mean dose of TL-GTV; and V13, V20,V30 and the mean dose of TL-PTV were statistically significant for the development of Grade ≥ 2 RP. No statistically significant results related to the development of Grade ≥ 2 RP were observed for the ipsilateral lung and the evaluation of PTV volume. A controlled and careful evaluation of the dose-volume histograms is important to assess Grade ≥ 2 RP development of the lung cancer patients treated with concurrent chemo-radiotherapy. In the light of the obtained data it can be said that RP development may be avoided by the proper analysis of the dose volume histograms and the application of optimal treatment plans.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/terapia , Pneumonite por Radiação/etiologia , Radioterapia Conformacional/efeitos adversos , Carcinoma de Pequenas Células do Pulmão/terapia , Quimiorradioterapia , Estudos de Coortes , Relação Dose-Resposta à Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos
5.
Asian Pac J Cancer Prev ; 15(17): 7401-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25227849

RESUMO

BACKGROUND: Postoperative chemoradiotherapy is accepted as standard treatment for stage IB-IV, M0 gastric cancer. Radiotherapy (RT) planning of gastric cancer is important because of the low radiation tolerance of surrounding critical organs. The purpose of this study was to compare the dosimetric aspects of 2-dimensional (2D) and 3-dimensional (3D) treatment plans, with the twin aims of evaluating the adequacy of 2D planning fields on coverage of planning target volume (PTV) and 3D conformal plans for both covering PTV and reducing the normal tissue doses. MATERIALS AND METHODS: Thirty-six patients with stage II-IV gastric adenocarcinoma were treated with adjuvant chemoradiotherapy using 3DRT. For each patient, a second 2D treatment plan was generated. The two techniques were compared for target volume coverage and dose to normal tissues using dose volume histogram (DVH) analysis. RESULTS: 3DRT provides more adequate coverage of the target volume. Comparative DVHs for the left kidney and spinal cord demonstrate lower radiation doses with the 3D technique. CONCLUSIONS: 3DRT produced better dose distributions and reduced radiation doses to left kidney and spinal cord compared to the 2D technique. For this reason it can be predicted that 3DRT will result in better tumor control and less normal tissue complications.


Assuntos
Adenocarcinoma/terapia , Órgãos em Risco , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Neoplasias Gástricas/terapia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Antimetabólitos Antineoplásicos/uso terapêutico , Quimiorradioterapia Adjuvante , Fluoruracila/uso terapêutico , Gastrectomia , Humanos , Imageamento Tridimensional , Leucovorina/uso terapêutico , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X , Complexo Vitamínico B/uso terapêutico
6.
Rare Tumors ; 2(2): e37, 2010 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-21139839

RESUMO

Gliosarcomas (GS) are highly malignant and rare tumors of the central nervous system with a poor prognosis. We report here on four patients with GS, the median survival for whom was 9.25 months. Prognosis of GS remains poor, and a multidisciplinary approach (surgery, radiation therapy, and chemotherapy) seems to be associated with slightly more prolonged survival times.

7.
World J Oncol ; 1(4): 158-166, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29147199

RESUMO

BACKGROUND: The aim of this study was to evaluate the palliative efficacy of localized external radiotherapy (RT) combined with systemic radionuclide (RN) therapy in patients who had multiple painful osseous metastases of different primary origins. METHODS: Thirty-three patients initially local external radiotherapy was delivered to the most symptomatic region in all patients. Then they received either Re 186 HEDP or Sm 153 EDTMP. The performance status was assessed according to ECOG scale. Before treatment, at the end of the radiotherapy and after the four weeks of systemic radionuclide therapy, analgesic intake and pain status were recorded by the RTOG scoring system, and EORTC QLQ C30 (Version 3.0 Turkish) questionnaire was performed to evaluate the quality of life. RESULTS: Improved performances of 33.3% for post radiation therapy and 50% for post radionuclide therapy in the ECOG scale were observed. Statistically significant correlations were found between the primary origins and decreased pain and analgesic intake (p < 0.05), but no differences were observed on the self assessment quality of life questionnaire. CONCLUSIONS: Both Re 186 HEDP, Sm 153 EDTMP are effective and safe in bone pain palliation as an adjuvant to local field radiation therapy of breast and prostate cancer patients, who also continued to receive chemotherapy and/or hormontherapy.

8.
Cell Biol Int ; 31(10): 1144-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17482482

RESUMO

Ionizing radiation is widely used for the treatment of solid tumors and it is thought to act by directly targeting tumor clonogens, also known as stem cells. Apoptosis is a genetically programmed mechanism of cell death often characterized by internucleosomal DNA cleavage. Although it has been previously shown that lymphocytes readily undergo apoptosis in patients receiving anticancer drugs or treatment with ionizing radiation, this is the first study to investigate the influence of radiotherapy and melatonin on apoptosis in rat lymphocytes at two different times of the day. Melatonin, a free radical scavenger, is an endogenous neurohormone predominantly synthesized in and secreted by the pineal gland. It has been shown that melatonin inhibits apoptosis in normal cells but it increases the rate of apoptosis in various cancer cells. Therefore, in the present study, the effect of melatonin on apoptosis in cultured lymphocytes was studied after total body irradiation (TBI) was given to rats in the morning (1 HALO) or evening (13 HALO) with morphological and DNA fragmentation analysis. Two-way analysis of variance (ANOVA) revealed that radiation increased the rate of apoptosis in rat lymphocytes after TBI, and melatonin treatment did not reduce the rate of apoptosis after TBI at either time point. We conclude that the lack of an effect of melatonin on the apoptosis rate in rat lymphocytes might be due to the dose-dependent effect of melatonin, the time course of apoptosis investigated, or the cell type in which apoptosis was examined.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Melatonina/farmacologia , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Raios gama , Masculino , Ratos , Ratos Wistar , Fatores de Tempo , Irradiação Corporal Total
9.
Med Hypotheses ; 68(3): 538-40, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17030099

RESUMO

Body weight loss is common in cancer patients, and is often associated with poor prognosis, it greatly impairs quality of life (QOL). Radiation therapy (RT) is used in head and neck cancers (HNC) either as a primary treatment or as an adjuvant therapy to surgery. Patients with HNC are most susceptible to malnutrition especially due to anorexia, which is aggravated by RT. Multiple pro-inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1beta (IL-1beta), interferon (IFN)-gamma and tumor necrosis factor-alpha(TNF-alpha), have been all associated with the development of both anorexia and oral mucositis. Radiation-induced mucositis occurs in almost all patients, who are treated for HNC, it could also cause weight loss. Ghrelin is a novel 28-amino acid peptide, which up-regulates body weight through appetite control, increase food intake, down-regulate energy expenditure and induces adiposity. Furthermore, ghrelin inhibits pro-inflammatory cytokines such as IL-1alpha, IL-1beta, TNF-alpha which may cause oral mucositis and aneroxia, which are the results of weight loss. Thus weight loss during RT is an early indicator of nutritional decline, we propose that recombinant ghrelin used prophylactically could be useful as an appetite stimulant; and preventive of mucositis because of its anti-inflammatory effect, it might help patients maintain weight over the course of curative RT of the HNC and can improve specific aspects of QOL. This issue warrants further studies.


Assuntos
Anorexia/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/radioterapia , Mucosite/diagnóstico por imagem , Mucosite/tratamento farmacológico , Hormônios Peptídicos/uso terapêutico , Radioterapia/efeitos adversos , Anorexia/prevenção & controle , Apetite , Grelina , Neoplasias de Cabeça e Pescoço/fisiopatologia , Humanos , Cintilografia
10.
Neurol India ; 54(4): 428-30, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17114859

RESUMO

Cases of glioblastoma multiforme (GBM) metastasizing to the leptomeninx or the intramedullary spine are quite rare and prognoses are relatively poor. We present three cases of GBM with spinal metastasis, one of which also had leptomeningeal dissemination. Three patients with GBM were admitted to our clinic for postoperative radiotherapy after surgery. Leptomeningeal metastasis and dissemination were diagnosed with magnetic resonance imaging. Radiotherapy provided only temporary relief from pain with small improvement in neurological deficit but no survival advantage.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/secundário , Neoplasias Meníngeas/secundário , Neoplasias da Medula Espinal/secundário , Adulto , Idoso , Evolução Fatal , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
11.
Med Hypotheses ; 66(5): 957-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16406688

RESUMO

Ionising radiation is known one of the most effective tools in the therapy of cancer but in many thoracic cancers, the total prescribed dose of radiation that can be safely administered to the target volume is limited by the risk of complications arising in the normal lung tissue. One of the major reasons for cellular injury after radiation is the formation of reactive oxygen species (ROS). Radiation pneumonitis is an acute phase side-effect which generally subsides after a few weeks and is followed by a chronic phase characterized by inflammation and fibrosis, that can develop months or years after irradiation. Carnosine is a dipeptide composed by the amino acids beta-histidine and l-alanine. The exact biological role of carnosine is not totally understood, but several studies have demonstrated that it possesses strong and specific antioxidant properties, protects against radiation damage,and promotes wound healing. The antioxidant mechanism of carnosine is attributed to its chelating effect against metal ions, superoxide dismutase (SOD)-like activity, ROS and free radicals scavenging ability . Either its antioxidant or anti-inflammatuar properties, we propose that carnosine ameliorates irradiation-induced lung injury. Thus, supplementing cancer patients to whom applied radiation therapy with carnosine, may provide an alleviation of the symptoms due to radiation-induced lung injury. This issue warrants further studies.


Assuntos
Carnosina/administração & dosagem , Citocinas/imunologia , Lesão Pulmonar , Pulmão/imunologia , Pneumonite por Radiação/imunologia , Pneumonite por Radiação/prevenção & controle , Proteção Radiológica/métodos , Carnosina/imunologia , Simulação por Computador , Humanos , Pulmão/efeitos dos fármacos , Modelos Imunológicos , Pneumonite por Radiação/etiologia , Protetores contra Radiação/uso terapêutico , Neoplasias Torácicas/imunologia , Neoplasias Torácicas/radioterapia
12.
Med Oncol ; 23(4): 499-505, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17303908

RESUMO

Combination chemoradiotherapy is a standard treatment for limited-stage small-cell lung cancer (LSSCLC). However, there is still controversery about the optimal timing of thoracic radiotherapy (TRT). In this study, the outcome of 70 patients who had received TRT at a dose of median 50 Gy (range, 46-60 Gy) with a second or third cycle of chemotherapy (CHT) either concurrently (n=41) or sequentially (n=29) were analyzed retrospectively. All patients were administered a median of five cycles (range, four to six cycles) cisplatin plus etoposide (EP) CHT. Prophylactic cranial radiotherapy was delivered to 30 (43%) patients. The median follow-up for all patients was 15 mo (range, 6-60 mo). The median overall survival was 19 mo in the concurrent arm vs 15 mo in the sequential arm. The 2-yr local control, disease-free survival, and overall survival rates were 60%, 19%, and 36%, respectively. The most common toxicity was esophagitis. However, there were no grade 3-4 esophagitis in either arm. Grade 3-4 hematologic toxicity, on the other hand, appeared significantly more in the concurrent arm (p < 0.001). Mid-course of once-daily TRT at a moderate total dose with CHT failed to show any improvement in survival. Additionally, there were no differences between concurrent and sequential CHT with TRT. However, acceptable toxicity rates support the use of once-daily fractionation to higher total dose of TRT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/terapia , Neoplasias Pulmonares/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cisplatino/uso terapêutico , Terapia Combinada , Fracionamento da Dose de Radiação , Etoposídeo/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia , Estudos Retrospectivos , Análise de Sobrevida , Taxa de Sobrevida
13.
J Otolaryngol ; 34(6): 379-83, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16343397

RESUMO

PURPOSE: Most authors recommend aggressive management for sinonasal carcinoma treatment. In an attempt to determine the optimal treatment, we assessed the treatment results of our patients with nasal cavity and paranasal sinus carcinoma. MATERIALS AND METHODS: From January 1980 to December 2001, 40 patients with malignant tumours of the nasal cavity and the paranasal sinuses were treated. The median follow-up was 6 years. Thirty-two patients had tumours originating from the maxillary sinus. Thirteen patients had T1-T2 (32.5%) tumours and 27 patients had T3-T4 (67.5%) tumours. The treatment method was surgery plus radiotherapy in 24 patients (60%) and radiotherapy alone in 16 patients (40%). RESULTS: The 5-year overall survival rate was 61%, whereas it was 65% for T1-T2 disease and 56% for T3-T4 disease. The 5-year local control rate was 58%, whereas it was 75% and 50% (p = .219) for T1-T2 and T3-T4 disease, respectively. In multivariate analysis; localization (p = .016), adjuvant radiotherapy (p = .040), local control (p = .05), and gender (p = .013 for female) were statistically significant factors. CONCLUSION: The prognosis for patients with tumours of the sinonasal area is dependent on localization, tumour stage, and treatment modality. Because the most common site of treatment failure is the primary site, efforts to maximize local control should be undertaken.


Assuntos
Carcinoma de Células Escamosas/terapia , Cavidade Nasal , Neoplasias Nasais/terapia , Neoplasias dos Seios Paranasais/terapia , Adolescente , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Criança , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Neoplasias do Seio Maxilar/mortalidade , Neoplasias do Seio Maxilar/terapia , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Neoplasias Nasais/mortalidade , Neoplasias dos Seios Paranasais/mortalidade , Prognóstico , Radioterapia Adjuvante , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
14.
Int J Radiat Oncol Biol Phys ; 63(5): 1347-53, 2005 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-16169671

RESUMO

PURPOSE: The current study reports on long-term quality of life (QoL) status after conventional radiotherapy in 187 nasopharyngeal carcinoma patients from 14 centers in Turkey. PATIENTS AND METHODS: Patients with the diagnosis of nasopharyngeal carcinoma, who were treated in 14 centers in Turkey with minimum 6 months of follow-up and were in complete remission, were asked to complete Turkish versions of EORTC QLQ-C30 questionnaire and the HN-35 module. Each center participated with the required clinical data that included age at diagnosis, gender, symptoms on admission, follow-up period, treatment modalities, radiotherapy dose, and AJCC 1997 tumor stage. Each patient's 33 QoL scores, which included function, global health status, and symptoms, were calculated as instructed in EORTC QLQ-C30 scoring manual. All of the scales and single-item measures range from 0 to 100. A high score represents a higher response level. Kruskal-Wallis and Mann-Whitney U nonparametric tests were used for comparisons. RESULTS: One hundred eighty-seven patients with median age of 46 years (range, 16-79 years) participated and completed the questionnaires. Median follow-up time was 3.4 years (range, 6 months-24 years). All patients have received external-beam radiotherapy. Beside external-beam radiotherapy, 59 patients underwent brachytherapy boost, 70 patients received concomitant chemotherapy, and 95 patients received adjuvant/neoadjuvant chemotherapy. Most of the patients in the analysis (75%) were in advanced stage (Stage III, n = 85 [45.4%]; Stage IV, n = 55 [29%]). Mean global health status was calculated as 73. Parameters that increased global health status were male gender, early-stage disease, and less than 4-year follow-up (p < 0.05). Functional parameters were better in males and in early-stage disease. Factors that yielded better symptom scores were short interval after treatment (10 scores), male gender (7 scores), and lower radiation dose (6 scores). Neoadjuvant or adjuvant chemotherapy did not have any effect on QoL, whereas concomitant chemotherapy adversely affected 5 symptom scores. CONCLUSION: Quality of life is adversely affected in our nasopharyngeal carcinoma patients treated with combined therapies. The factors that adversely affect quality of life are advanced tumor stage, female gender, and long-term follow-up. Further controlled studies to evaluate both preradiotherapy and postradiotherapy status are necessary to clarify the contribution of each treatment modality to QoL.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Adulto , Idoso , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/patologia , Fatores Sexuais , Estatísticas não Paramétricas , Turquia
15.
Oncology ; 69(1): 44-51, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16103734

RESUMO

OBJECTIVE: To investigate the early protective effects of amifostine against radiation-induced damage on rat testis tissue. METHODS: Eighty adult male Wistar rats were randomized to 4 groups: Saline solution was given to group A for control, 200 mg/kg amifostine (WR-2721) to group B, a single fraction of 6 Gy local irradiation to testes in group C and 200 mg/kg amifostine 15-30 min before 6 Gy testicular irradiation to group D. Animals were sacrificed 3 weeks after treatment and their testes were removed for macroscopic, microscopic and ultrastructural histopathological examination. RESULTS: The weights, widths and lengths of testes in the last 3 groups had decreased significantly when compared with the control group, but the decrease in widths after irradiation was found to be significantly less only in the amifostine plus radiation group. There was a significant reduction of testis weights in relation to the individual body weights in the irradiated testes compared with the other groups (p < 0.005), while there was no significant change of testis weight/total body weight ratio in amifostine plus irradiation group. Spermatogonium A and primary spermatocyte counts were also less in the treatment groups, and primary spermatocyte numbers were significantly higher in amifostine plus radiation group when compared with radiation alone group (p < 0.005). Pretreatment with amifostine reduced the decrease of primary spermatocyte counts by a factor of 1.28. Electron microscopic analysis did not show any cytotoxic effect of amifostine alone, and furthermore, ultrastructural findings were normal with the addition of amifostine prior to irradiation, though there was damage in the radiation exposure group. CONCLUSION: Amifostine when given alone by itself appears to cause adverse alterations in testis tissue; however, it has a radioprotective effect on spermiogenetic cells when used prior to radiation.


Assuntos
Amifostina/farmacologia , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Testículo/efeitos da radiação , Animais , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia , Microscopia Eletrônica , Lesões por Radiação/patologia , Distribuição Aleatória , Ratos , Ratos Wistar , Epitélio Seminífero/efeitos da radiação , Epitélio Seminífero/ultraestrutura , Contagem de Espermatozoides , Testículo/patologia
18.
Eksp Onkol ; 26(1): 71-4, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15112584

RESUMO

AIM: To examine the state of the oxidant-antioxidant system in the liver of guinea pig caused by high doses of ionizing radiation in the early period. METHODS: The research was carried out on guinea pigs irradiated with the doses of 8 Gy (group 2) or 15 Gy (group 3) (single dose/whole body) in comparison with control group (group 1). The levels of thiobarbituric acid reactive substances (TBARS) and glutathione (GSH), the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and the levels of selenium in the liver were measured. RESULTS: TBARS levels in the irradiated animals were markedly higher than those in controls. In group 3, GSH levels and GSH-Px activity were significantly increased while activity of SOD and CAT were significantly decreased compared to groups 1 and 2. Liver selenium levels were not influenced by irradiation. CONCLUSION: The data have shown that gamma-irradiation at the doses of 8 Gy or 15 Gy results in significant increase in free radical formation while antioxidant enzymes were affected only at a dose of 15 Gy.


Assuntos
Antioxidantes/metabolismo , Raios gama/efeitos adversos , Fígado/efeitos da radiação , Estresse Oxidativo/efeitos da radiação , Animais , Catalase/metabolismo , Relação Dose-Resposta à Radiação , Glutationa Peroxidase/metabolismo , Cobaias , Fígado/enzimologia , Fígado/metabolismo , Doses de Radiação , Selênio/metabolismo , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Irradiação Corporal Total
19.
Indian J Exp Biol ; 41(3): 267-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15267159

RESUMO

Different doses of irradiation were performed in which group 1 (non-irradiated), group 2 (8 Gy/single dose/whole body) and group 3 (15 Gy/single dose/whole body) were formed of guinea pigs. After 24 hr of radiation exposure the levels of lipid peroxidation product, malondialdehyde, (MDA), glutathione (GSH) and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were measured in the whole kidney. The MDA content increased in animals irradiated with 8 and 15 Gy. And group 3 showed an increase the level of MDA. GSH contents of kidney in group 2 and 3 increased. The activity of SOD decreased markedly in group 3 when compared with control group. The activity of GSH-Px decreased significantly in group 2 and group 3 in comparison to controls. It may be concluded that a high dose of ionizing irradiation cause excessive oxidative stress in kidney.


Assuntos
Adaptação Fisiológica/efeitos da radiação , Antioxidantes/farmacologia , Rim/efeitos dos fármacos , Rim/efeitos da radiação , Adaptação Fisiológica/efeitos dos fármacos , Animais , Glutationa/metabolismo , Cobaias , Rim/metabolismo , Malondialdeído/metabolismo
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