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1.
Rep Pract Oncol Radiother ; 26(1): 50-58, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33948302

RESUMEN

BACKGROUND: Symmetry and flatness are two quantities which should be evaluated in the commissioning and quality control of an electron beam in electron beam radiotherapy. The aim of this study is to compare symmetry and flatness obtained using three different dosimeters for various small and large fields in electron beam radiotherapy with linac. MATERIALS AND METHODS: Beam profile measurements were performed in a PTW water phantom for 10, 15 and 18 MeV electron beams of an Elekta Precise linac for small and large beams (1.5 × 1.5 cm2 to 20 × 20 cm2 field sizes). A Diode E detector and Semiflex-3D and Advanced Markus ionization chambers were used for dosimetry. RESULTS: Based on the obtained results, there are minor differences between the responses from different dosimeters (Diode E detector and Semiflex-3D and Advanced Markus ionization chambers) in measurement of symmetry and flatness for the electron beams. The symmetry and flatness values increase with increasing field size and electron beam energy for small and large field sizes, while the increases are minor in some cases. CONCLUSIONS: The results indicate that the differences between the symmetry and flatness values obtained from the three dosimeter types are not practically important.

2.
J Xray Sci Technol ; 28(4): 641-658, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32390644

RESUMEN

OBJECTIVE: Several physical factors such as dose rate and photon energy may change response and sensitivity of polymer gel dosimeters. This study aims to evaluate the R2-dose response and sensitivity dependence of PASSAG-U gel dosimeters with 3% and 5% urea on dose rate and photon energy. MATERIALS AND METHODS: The PASSAG-U gel dosimeters were prepared under normal atmospheric conditions. The obtained gel dosimeters were irradiated to different dose rates (100, 200, and 300 cGy/min) and photon energies (6 and 15 MV). Finally, responses (R2) of the PASSAG-U gel dosimeters with 3% and 5% urea were analyzed by MRI technique at 1, 10, 14 days after the irradiation process. RESULTS: The findings showed that the R2-dose responses of PASSAG-U gel dosimeters with 3% and 5% urea do not vary under the differently evaluated dose rates and photon energies. The R2-dose sensitivity of PASSAG-U polymer gel dosimeter with 3% urea does not change under the differently evaluated dose rates and photon energies, but it changes for PASSAG-U polymer gel dosimeter with 5% urea. The dose resolution values ranged from 0.20 to 0.86 Gy and from 0.27 to 2.20 Gy for the PASSAG-U gel dosimeter with 3% and 5% urea for the different dose rates and photon energies, respectively. Furthermore, it was revealed that the R2-dose response and sensitivity dependence of PASSAG-U gel dosimeters with 3% and 5% urea on dose rate and photon energy can vary over post irradiation time. CONCLUSIONS: The study results demonstrated that dosimetric characteristics (dependence of dose rate and photon energy, and dose resolution) of PASSAG-U gel dosimeter with 3% were better than those of PASSAG-U gel dosimeter with 5% urea.


Asunto(s)
Dosímetros de Radiación , Relación Dosis-Respuesta en la Radiación , Geles , Imagen por Resonancia Magnética , Fotones , Polímeros , Dosis de Radiación , Radiometría , Sensibilidad y Especificidad , Urea/análisis
3.
Medicina (Kaunas) ; 55(8)2019 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-31366142

RESUMEN

Background and objectives: Pneumonitis and fibrosis are the most common consequences of lung exposure to a high dose of ionizing radiation during an accidental radiological or nuclear event, and may lead to death, after some months to years. So far, some anti-inflammatory and antioxidant agents have been used for mitigation of lung injury. In the present study, we aimed to detect possible mitigatory effects of melatonin and metformin on radiation-induced pneumonitis and lung fibrosis. Materials and methods: 40 male mice were divided into 4 groups (10 mice in each). For control group, mice did not receive radiation or drugs. In group 2, mice were irradiated to chest area with 18 Gy gamma rays. In groups 3 and 4, mice were first irradiated similar to group 2. After 24 h, treatment with melatonin as well as metformin began. Mice were sacrificed after 100 days for determination of mitigation of lung pneumonitis and fibrosis by melatonin or metformin. Results: Results showed that both melatonin and metformin are able to mitigate pneumonitis and fibrosis markers such as infiltration of inflammatory cells, edema, vascular and alveolar thickening, as well as collagen deposition. Conclusion: Melatonin and metformin may have some interesting properties for mitigation of radiation pneumonitis and fibrosis after an accidental radiation event.


Asunto(s)
Melatonina/uso terapéutico , Metformina/uso terapéutico , Neumonitis por Radiación/tratamiento farmacológico , Animales , Antioxidantes/metabolismo , Antioxidantes/uso terapéutico , Modelos Animales de Enfermedad , Melatonina/metabolismo , Metformina/metabolismo , Ratones , Sustancias Protectoras/metabolismo , Sustancias Protectoras/uso terapéutico , Exposición a la Radiación/efectos adversos , Exposición a la Radiación/estadística & datos numéricos , Neumonitis por Radiación/patología
4.
Medicina (Kaunas) ; 55(7)2019 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-31252673

RESUMEN

Background: Radiation-induced heart injury can lead to increased risk of heart failure, attack, and ischemia. Some studies proposed IL-4 and IL-13 as two important cytokines that are involved in late effects of ionizing radiation. On the other hand, these cytokines may, through upregulation of Duox1 and Duox2, induce chronic oxidative stress, inflammation, and fibrosis. In this study, we evaluated the upregulation of Duox1 and Duox2 pathways in hearts following chest irradiation in rats and then detected possible attenuation of them by melatonin. Materials and Methods: Twenty male Wistar rats were divided into four groups: (1) control; (2) melatonin treated (100 mg/kg); (3) radiation (15 Gy gamma rays); (4) melatonin treated before irradiation. All rats were sacrificed after 10 weeks and their heart tissues collected for real-time PCR (RT-PCR), ELISA detection of IL-4 and IL-13, as well as histopathological evaluation of macrophages and lymphocytes infiltration. Results: Results showed an upregulation of IL-4, IL4ra1, Duox1, and Duox2. The biggest changes were for IL4ra1 and Duox1. Treatment with melatonin before irradiation could attenuate the upregulation of all genes. Melatonin also caused a reduction in IL-4 as well as reverse infiltration of inflammatory cells. Conclusion: Duox1 and Duox2 may be involved in the late effects of radiation-induced heart injury. Also, via attenuation of these genes, melatonin can offer protection against the toxic effects of radiation on the heart.


Asunto(s)
Oxidasas Duales/efectos de la radiación , Melatonina/farmacología , Regulación hacia Arriba/efectos de la radiación , Análisis de Varianza , Animales , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática/métodos , Cardiopatías Congénitas , Masculino , Melatonina/uso terapéutico , Factores Protectores , Traumatismos por Radiación , Ratas , Ratas Wistar , Regulación hacia Arriba/fisiología
5.
Br J Nutr ; 113(2): 321-30, 2015 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-27028002

RESUMEN

Improvement of insulin resistance and inflammation is a basic strategy in the management of type 2 diabetes. There is limited evidence that prebiotics improve insulin resistance and inflammation. However, the ameliorating effect of resistant dextrin, as a prebiotic, on insulin resistance and inflammation in patients with type 2 diabetes has not been investigated so far. Therefore, the present study aimed to examine the effects of resistant dextrin on insulin resistance and inflammation in type 2 diabetic patients. In a randomised controlled clinical trial, fifty-five women with type 2 diabetes were assigned to two groups: the intervention group (n 30) and the control group (n 25). The intervention group received a daily supplement of 10 g resistant dextrin and the control group received a similar amount of maltodextrin as placebo for 8 weeks. Fasting plasma glucose (FPG), HbA1c, insulin, high-sensitivity C-reactive protein (hs-CRP), IL-6, TNF-α, malondialdehyde (MDA) and serum endotoxin concentrations were measured before and after the intervention. Data were analysed using SPSS (version 13). Paired and unpaired t tests and ANCOVA were used to compare quantitative variables after the intervention. Patients supplemented with resistant dextrin exhibited a significant decrease in fasting insulin (20.1 pmol/l, 22.8%), homeostasis model assessment of insulin resistance (1.3, 24.9%), quantitative insulin sensitivity check index (0.2, 7.2%), IL-6 (1.4 pg/ml, 28.4 %), TNF-α (5.4 pg/ml, 18.8 %), MDA (1.2 nmol/ml, 25.6 %) and endotoxin (6.2 endotoxin units/ml, 17.8%) concentrations than those supplemented with maltodextrin (P< 0.05). Decreases in FPG (0.05 mmol/l, 0.6%), HbA1c (0.5%, 9.6%) and hs-CRP (2.7 ng/ml, 35.1%) concentrations in the resistant dextrin group were not significant when compared with the maltodextrin group. In conclusion, resistant dextrin supplementation can modulate inflammation and improve insulin resistance in women with type 2 diabetes.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Dextrinas/uso terapéutico , Diabetes Mellitus Tipo 2/dietoterapia , Hipoglucemiantes/uso terapéutico , Resistencia a la Insulina , Prebióticos , Adulto , Anciano , Antioxidantes/efectos adversos , Antioxidantes/uso terapéutico , Biomarcadores/sangre , Índice de Masa Corporal , Citocinas/sangre , Dextrinas/efectos adversos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/inmunología , Diabetes Mellitus Tipo 2/metabolismo , Método Doble Ciego , Endotoxinas/sangre , Ingestión de Energía , Femenino , Estudios de Seguimiento , Humanos , Irán , Malondialdehído/sangre , Persona de Mediana Edad , Sobrepeso/complicaciones , Prebióticos/efectos adversos
6.
J Health Popul Nutr ; 33(1): 157-67, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25995732

RESUMEN

This cross-sectional study was aimed to better clarify the associations of insulin resistance (IR) with endocrinometabolic parameters in polycystic ovary syndrome (PCOS). Anthropometric measurements, endocrine and metabolic profiles, and the presence of IR and metabolic syndrome (MetS) were assessed in 63 overweight or obese PCOS patients subdivided into insulin-resistant (IR) and insulin-sensitive (IS) groups. Fasting insulin concentration and HOMA-IR were higher (p<0.001), and quantitative insulin check index (QUICKI), glucose-to-insulin ratio (p<0.001), and high-density lipoprotein cholesterol (HDL-C) (p=0.012) were lower in IR group. MetS (p=0.034) and obesity (p=0.038) were more prevalent in IR group. For all PCOS patients, significant correlations of total cholesterol (TC) with dehydroepiandrosterone sulphate (DHEAS) (r=-0.27, p=0.031), HDL-C with QUICKI (r=0.26, p=0.036) were found. Partial correlations also showed significant associations between TG and BS2h (r=0.30, p=0.026) as well as TC and LH/FSH ratio (r=0.30, p=0.032). When the patients were divided into IR and IS groups, significant correlations of low-density lipoprotein cholesterol (LDL-C) with luteinizing hormone (LH) (r=0.50, p=0.017) as well as TC (r=0.42, p=0.043) and LDL-C (r=0.50, p=0.016) with LH/FSH ratio were observed in IR group. However, partial correlation suggested significant associations of HDL-C with testosterone (r=-0.35, p=0.049) as well as serum LDL-C (r=0.38, p=0.033), HDL-C (r=-0.32, p=0.047), and TC (r=0.34, p=0.056) with progesterone level only in the IS group. The findings of this study indicated that lipid abnormalities may occur in PCOS, irrespective of IR.


Asunto(s)
Hormonas/sangre , Resistencia a la Insulina/fisiología , Lípidos/sangre , Síndrome Metabólico/sangre , Obesidad/sangre , Síndrome del Ovario Poliquístico/sangre , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Síndrome Metabólico/complicaciones , Obesidad/complicaciones , Síndrome del Ovario Poliquístico/complicaciones , Adulto Joven
7.
ScientificWorldJournal ; 2014: 621570, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25431791

RESUMEN

Gamma radiation induces the generation of free radicals, leading to serious cellular damages in biological systems. Radioprotectors act as prophylactic agents that are administered to shield normal cells and tissues from the deleterious effects of radiation. Melatonin synergistically acts as an immune-stimulator and antioxidant. We investigated the possible radioprotective role of melatonin (100 mg/kg i.p.) against lethal-whole-body radiation- (10 Gy) induced sickness, body weight loss, and mortality in rats. Results of the present study suggest that exposure to lethal-whole-body radiation incurred mortality, body weight loss, and apoptosis and it also depleted the immunity and the antioxidant status of the rats. Our results show that melatonin pretreatment provides protection against radiation induced mortality, oxidative stress, and immune-suppression. The melatonin pretreated irradiated rats showed less change in body weight as compared to radiation only group. On the other hand, melatonin appeared to have another radioprotective role, suggesting that melatonin may reduce apoptosis through a caspase-3-mediated pathway by blocking caspase-3 activity.


Asunto(s)
Antioxidantes/farmacología , Rayos gamma/efectos adversos , Melatonina/farmacología , Traumatismos por Radiación/prevención & control , Protectores contra Radiación/farmacología , Animales , Apoptosis/efectos de la radiación , Peso Corporal , Caspasa 3/genética , Caspasa 3/metabolismo , Catalasa/metabolismo , Expresión Génica/efectos de la radiación , Glutatión Peroxidasa/metabolismo , Inmunidad Innata/efectos de la radiación , Linfocitos/inmunología , Linfocitos/patología , Linfocitos/efectos de la radiación , Masculino , Estrés Oxidativo/efectos de la radiación , Traumatismos por Radiación/etiología , Traumatismos por Radiación/inmunología , Traumatismos por Radiación/mortalidad , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo , Análisis de Supervivencia , Irradiación Corporal Total
8.
Int J Food Sci Nutr ; 65(1): 117-23, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24059649

RESUMEN

There is limited evidence on the effects of prebiotics on inflammation. Therefore, the aim of this study was to evaluate the effects of inulin supplementation on inflammatory indices and metabolic endotoxemia in patients with type 2 diabetes mellitus. The participants included diabetic females (n = 49). They were divided into an intervention group (n = 24) as well as a control group (n = 25) and received 10 g/d inulin or maltodextrin for 8 weeks, respectively. Fasting blood sugar (FBS), HbA1c, insulin, high-sensitive C-reactive protein (hs-CRP), tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), and plasma lipopolysaccharide (LPS) were measured pre and post intervention. Inulin-supplemented patients exhibited a significant decrease in FBS (8.5%), HbA1c (10.4%), fasting insulin (34.3%), homeostasis model assessment of insulin resistance (HOMA-IR) (39.5%), hs-CRP (35.6%), TNF-α (23.1%), and LPS (27.9%) compared with the maltodextrin group (p < 0.05). Increase in IL-10 was not significant in inulin compared with the maltodextrin group. It can be concluded that inulin supplementation seems to be able to modulate inflammation and metabolic endotoxemia in women with type 2 diabetes.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Diabetes Mellitus Tipo 2/dietoterapia , Endotoxemia/complicaciones , Inulina/uso terapéutico , Obesidad/complicaciones , Sobrepeso/complicaciones , Prebióticos , Adulto , Anciano , Antiinflamatorios no Esteroideos/economía , Índice de Masa Corporal , Terapia Combinada , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/inmunología , Método Doble Ciego , Endotoxemia/sangre , Endotoxemia/inmunología , Femenino , Estudios de Seguimiento , Humanos , Hipoglucemiantes/uso terapéutico , Inmunomodulación , Resistencia a la Insulina , Inulina/economía , Irán , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/sangre , Persona de Mediana Edad , Obesidad/inmunología , Sobrepeso/inmunología , Prebióticos/economía , Adulto Joven
9.
Int J Hyperthermia ; 29(3): 256-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23517402

RESUMEN

PURPOSE: This study has been conducted to evaluate the effect of urea on aggregation responses of heat-treated platelets. MATERIALS AND METHODS: The urea was added to platelet-rich plasma (PRP) samples in final concentrations of 50 and 100 mM. PRP samples, with or without exogenous urea, were incubated at 37 °C, 39 °C and 41 °C for 90 min and then were stimulated with adenosine diphosphate (ADP) or epinephrine for measuring of platelet aggregation responses. The average reduction in aggregability of heat-treated samples with reference to mean value obtained for control samples treated at 37 °C was expressed as inhibition percentage. RESULTS: Aggregation responses of the samples treated in the presence of 50 mM and 100 mM urea were significantly less inhibited by hyperthermia treatments compared with those treated without exogenous urea. CONCLUSION: The results indicate that the inhibitory effect of hyperthermia on platelet aggregation responses could be significantly modulated by urea.


Asunto(s)
Fiebre , Agregación Plaquetaria/efectos de los fármacos , Urea/administración & dosificación , Adenosina Difosfato , Epinefrina , Humanos , Plasma Rico en Plaquetas/efectos de los fármacos , Plasma Rico en Plaquetas/fisiología
10.
Iran J Kidney Dis ; 17(3): 126-134, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37337796

RESUMEN

INTRODUCTION: Indoxyl sulfate (IS) and para-cresol (p-cresol) are uremic toxins with high protein bonding index that accumulate in the body with decreasing kidney function. The main purpose of the current investigation was to compare the concentration of p-cresol and IS in serum of the type II diabetic individuals with and without nephropathy. METHODS: Fifty-five patients with type II diabetes mellitus were divided into two groups: case and control. The case group consisted of 26 diabetic patients with nephropathy (proteinuria and serum creatinine below 1.5 mg/dL) without any other kidney diseases. The control group included 29 patients without diabetic nephropathy. Patients with advanced heart disease, cerebrovascular accident and other inflammatory or infectious diseases were excluded. Five mL of venous blood was taken from each patient in the morning fasting state. Then other laboratory tests including serum uric acid and creatinine levels, serum urea nitrogen, lipids and glucose were measured by standard methods. P-Cresol and IS levels were measured by the spectrofluorimetric method after extraction. We also filled out a checklist with information regarding the duration of their disease, medication history (oral or injectable), and other demographic information. There were no significant differences between the two groups regarding the investigated factors Results. There were no significant difference among the investigated factors between the two groups (P > .05) except for the serum creatinine, proteinuria and estimated glomerular filtration rate, where the mean values of cases were considerably higher than those of the controls. Serum IS and p-cresol levels were also significantly higher in the case group (P < .05). CONCLUSION: According to the findings, it seems that IS, and p-cresol may play a role in the development of diabetic nephropathy and other complications of diabetes mellitus.  DOI: 10.52547/ijkd.7266.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Humanos , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/etiología , Indicán/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Creatinina , Ácido Úrico , Proteinuria
11.
Curr Radiopharm ; 15(4): 332-340, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35747962

RESUMEN

PURPOSE: Despite advances in medical technology, radiation-induced dermatitis occurs in 95% of cancer patients receiving radiation therapy. Currently, there is no standard and effective treatment for the prevention or control of radiation dermatitis. The aim of this study was to determine the efficacy of nano-curcumin in alleviating the radiation-induced skin reactions (RISRs) in breast cancer patients. METHODS: A randomized, triple-blinded, placebo-controlled clinical trial was performed on 42 patients with breast cancer. The patients were randomly allocated to receive radiotherapy plus placebo (control group) and radiotherapy plus 80 mg/day nano-curcumin capsules (treatment group) up to two weeks after the end of treatment. Then, the RISRs (graded by the radiation therapy oncology group (RTOG) scale) and pain level of the patients were evaluated at baseline and weekly. Finally, the results were analyzed by T-test and Pearson chi-square test. RESULTS: According to the RTOG scale, 0%, 14.28%, and 85.71% of patients in the control group showed grades 0, 1, and 2 RISRs, respectively. In the treatment group, it was observed that 9.52%, 47.61%, and 42.85% of patients had grades 0, 1, and 2 RISRs, respectively. Compared to the control group, it was found that concomitant use of the nano-curcumin supplement did not significantly reduce the RISR severity during the first to sixth weeks (P > 0.05); however, there was a significant difference at week 7 (P = 0.01). Moreover, the patient-reported pain, as the secondary endpoint, was significantly reduced in the treatment group compared with the control group (P < 0.05). CONCLUSIONS: In general, it was found that the administration of nano-curcumin could alleviate radiation- induced skin toxicity of breast cancer patients, but this effect was not significant.


Asunto(s)
Neoplasias de la Mama , Curcumina , Radiodermatitis , Humanos , Femenino , Curcumina/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/radioterapia , Método Doble Ciego , Radiofármacos/uso terapéutico , Radiodermatitis/tratamiento farmacológico , Radiodermatitis/prevención & control , Dolor/tratamiento farmacológico
12.
J Biomed Phys Eng ; 12(2): 111-116, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35433523

RESUMEN

Background: The dose values obtained from procedures of diagnostic radiology are relatively low. To accurately and precisely measure the dose values in this dose range, it is necessary to know the characteristics of dosimeters. Objective: The aim of this study was to evaluate several thermoluminescent characteristics of GR-200, TLD-700H and TLD-100 for low dose measurement. Material and Methods: In this experimental study, linearity, repeatability, dose rate and photon energy dependence of different TLD materials were investigated in a 0.05-10 mGy range dose. It is noteworthy that the data obtained from TLD-100 were considered as reference and the data obtained from two other types of TLDs were compared with them. Results: For all three types of TLD materials, there are linear relations between absorbed dose values to TLDs and their responses. TLD-100 and TLD-700H have very low sensitivity than GR-200. For GR-200 and TLD-100, the coefficients of variation values (%) are 3.00% and 2.01%, respectively, that these values are within the tolerance limit (<7.5%). However, this value for TLD-700H is 10.85% which it is more than the reported tolerance limit. Furthermore, remarkable effects of dose rate and photon energy dependence on the responses of GR-200 are not observed in a 0.5-4 mGy dose range; nevertheless, remarkable effects of dose rate and photon energy dependence on the responses of TLD-100 and TLD-700H are found in this dose range. Conclusion: The evaluated thermoluminescent characteristics for GR-200 are better than two other types of TLDs (TLD-100 and TLD-700H) for low dose values.

13.
Curr Radiopharm ; 15(3): 236-241, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35306999

RESUMEN

BACKGROUND: Breast cancer is one of the most common types of malignancies in the world. Cancer resistance is an unavoidable consequence of therapy with radiation or other modalities. Ongoing research aims to improve cancer response to therapy. AIM: The aim of this study was to evaluate the possible sensitization effect of imperatorin (IMP) in combination with external radiotherapy (ERT) or HT. METHODS: After treatment of MCF-7 breast cancer cells with IMP, cells were exposed to 4 Gy X-rays or HT (42 °C for 1 hour). The viability of MCF-7 cells was measured using an MTT assay. Furthermore, the expression of pro-apoptotic genes, including Bax, Bcl-2, caspase-3, caspase-8, and caspase- 9, was investigated using real-time PCR. The sensitizing effect of IMP in combination with ERT or HT was calculated and compared to ERT or HT alone. RESULTS: Results showed an increase in the expression of pro-apoptotic genes and downregulation of anti-apoptotic Bcl-2 following ERT and HT. Furthermore, cell viability was reduced following these treatments. IMP was able to augment these effects of ERT and HT. CONCLUSION: IMP could increase the efficiency of HT and ERT. This effect of IMP may suggest it as an adjuvant for increasing the therapeutic efficiency of ERT.


Asunto(s)
Neoplasias de la Mama , Furocumarinas , Hipertermia Inducida , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Femenino , Furocumarinas/uso terapéutico , Humanos , Células MCF-7
14.
J Am Coll Nutr ; 30(3): 210-5, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21896879

RESUMEN

OBJECTIVE: Metformin is widely used in patients with type 2 diabetes, but it may decrease vitamin B12 and folate levels and increase levels of homocysteine (Hcy). Hyperhomocysteinemia (HHC) and hyperglycemia induce oxidative stress in type 2 diabetes. Thus, this study was performed to determine the effects of folate supplementation on the concentration of homocysteine, total antioxidant capacity (TAC), and malondialdehyde (MDA). METHODS: This was a double-blind randomized controlled clinical trial. Sixty-eight men with type 2 diabetes participated in the study with written consent. Patients were divided randomly into 2 groups: folic acid 5 mg/d and placebo. All patients received the tablets for 8 weeks. Anthropometric and nutrient intake data were obtained from each patient. Baseline and eighth-week homocysteine, total antioxidant capacity, malondialdehyde, folate, and B12 levels were measured. RESULTS: After folate supplementation in the folic acid group, homocysteine was significantly decreased (15.1 ± 3.2 to 12.1 ± 3.1 µmol/L, p < 0.001) and folate and B12 levels were significantly increased (p < 0.001). A significant increase in total antioxidant capacity (0.96 ± 0.2 to 1.14 ± 0.3 mmol Fe2+/L, p < 0.001) and a significant decrease in malondialdehyde (2.6 ± 0.7 to 1.7 ± 0.2 µmol/L, p < 0.001) were observed in the folic acid group, whereas no significant changes occurred in the placebo group (p > 0.05). CONCLUSION: Pharmacological doses of folate supplementation lowered plasma homocysteine and serum malondialdehyde levels and improved serum total antioxidant capacity and folate and B12 levels in patients with type 2 diabetes.


Asunto(s)
Antioxidantes/administración & dosificación , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Suplementos Dietéticos , Ácido Fólico/administración & dosificación , Homocisteína/efectos de los fármacos , Malondialdehído/sangre , Administración Oral , Anciano , Antioxidantes/análisis , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Homocisteína/sangre , Humanos , Masculino , Metformina/efectos adversos , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Vitamina B 12/sangre
15.
Oral Radiol ; 37(1): 80-85, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32065334

RESUMEN

OBJECTIVE: Although radiation exposure associated with dental radiography is relatively low, patient exposure must be kept practically low. Therefore, it is necessary for each country to establish its own diagnostic reference levels (DRLs) suitable for its equipment and practice. In the present study, dose-width product (DWP) values for panoramic dental radiography were measured and a local DRL was established. METHODS: Five panoramic devices from five radiology clinics of Kashan, Iran were selected to measure the DWP values of panoramic dental radiography. To investigate the DWP values, the parameters of each patient's exposure (e.g., tube voltage, tube current, and exposure time) at these five radiology clinics were extracted. Then, the dose value received by each patient was measured based on a CT pencil chamber. Finally, the overall median DWP values for the patients with small, medium, and large sizes were obtained, and these values were considered as the local DRLs for panoramic dental radiography. RESULTS: A total of 99 adult patients were included in the present study. The findings demonstrated that the median and third-quartile DWP values for these five radiology clinics ranged from 42.3 to 94.3 and 49.7 to 142.8 mGy mm, respectively. The local DRL values, which were established as the overall median DWP values, were 43.4, 52.0, and 80.3 mGy  mm for the adults with small, medium, and large sizes, respectively. CONCLUSION: The local DRL proposed in this study for the adult with standard/medium size was lower than those proposed by other reports and seemed acceptable for panoramic radiography in Kashan, Iran.


Asunto(s)
Niveles de Referencia para Diagnóstico , Radiometría , Adulto , Humanos , Irán , Dosis de Radiación , Radiografía Panorámica
16.
J Med Signals Sens ; 10(4): 286-294, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33575201

RESUMEN

BACKGROUND: Various factors effecting deposited energy and dose enhancement ratio (DER) in the simplified model of cell caused by the interaction of a cluster of gold nanoparticles (GNPs) with electron beams were assessed, and the results were compared with other sources through Geant4 Monte Carlo simulation toolkit. METHOD: The effect of added GNPs on the DNA strand breaks level, irradiated to electron, proton, and alpha beams, is assessed. RESULTS: Presence of GNPs in the cell makes DER value more pronounced for low-energy photons rather than electron beam. Moreover, the results of DER values did not show any significant increase in absorbed dose in the presence of GNP for proton and alpha beam. Moreover, the results of DNA break with GNPs for proton and alpha beam were negligible. It is demonstrated that as the sizes of the GNPs increase, the DER is enlarged until a certain size for 40 keV photons, while there is no striking change for 50 keV electron beam when the size of the GNPs changes. The results indicate that although energy deposited in the cell for electron beam is more than low-energy photon, DER values are low compared to photon. CONCLUSION: Larger GNPs do not show any preference over smaller ones when irradiated through electron beams. It is proved that GNPs do not significantly increase single-strand breaks (SSBs) and double-strand breaks during electron irradiation, while there exists a direct relationship between SSB and energy.

17.
Radiol Phys Technol ; 13(3): 296-305, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32691343

RESUMEN

The usage of dosimetry of small fields in radiotherapy to measure radiation dose is difficult because of high-dose gradients, lateral electronic disequilibrium, and detector volume effects. In this study, three dosimeters namely, Markus, Semiflex 3D, and Diode E were tested using the Elekta-accelerator electron beams. The electron beam parameters, penumbra, and output factor were determined using these dosimeters for each field size and energy. According to the results, Diode E and Advanced Markus exhibited the greatest difference in Rq among the electron beam parameters. Furthermore, the greatest difference in penumbra was observed between Diode E and Advanced Markus for the field size of 3 cm2 at 10 MeV. In terms of output factor, three dosimeters exhibited the greatest difference between Diode E and Advanced Markus for the field size of 3 cm2 at 10 MeV. The findings indicate that the Semiflex 3D can be regarded as an appropriate dosimeter for electron small-field dosimetry.


Asunto(s)
Electrones , Radiometría/métodos , Aceleradores de Partículas , Fantasmas de Imagen , Radiometría/instrumentación
18.
Artículo en Inglés | MEDLINE | ID: mdl-31713500

RESUMEN

AIM: In this study, we aimed to determine possible mitigation of radiationinduced toxicities in the duodenum, jejunum and colon using post-exposure treatment with resveratrol and alpha-lipoic acid. BACKGROUND: After the bone marrow, gastrointestinal system toxicity is the second critical cause of death following whole-body exposure to radiation. Its side effects reduce the quality of life of patients who have undergone radiotherapy. Resveratrol has an antioxidant effect and stimulates DNA damage responses (DDRs). Alpha-lipoic acid neutralizes free radicals via the recycling of ascorbic acid and alpha-tocopherol. OBJECTIVE: This study is a pilot investigation of the mitigation of enteritis using resveratrol and alpha-lipoic acid following histopathological study. METHODS: 60 male mice were randomly assigned to six groups; control, resveratrol treatment, alpha-lipoic acid treatment, whole-body irradiation, irradiation plus resveratrol, and irradiation plus alpha-lipoic acid. The mice were irradiated with a single dose of 7 Gy from a cobalt-60 gamma-ray source. Treatment with resveratrol or alpha-lipoic acid started 24 h after irradiation and continued for 4 weeks. All mice were sacrificed after 30 days for histopathological evaluation of radiation-induced toxicities in the duodenum, jejunum and colon. RESULTS AND DISCUSSION: Exposure to radiation caused mild to severe damages to vessels, goblet cells and villous. It also led to significant infiltration of macrophages and leukocytes, especially in the colon. Both resveratrol and alpha-lipoic acid were able to mitigate morphological changes. However, they could not mitigate vascular injury. CONCLUSION: Resveratrol and alpha-lipoic acid could mitigate radiation-induced injuries in the small and large intestine. A comparison between these agents showed that resveratrol may be a more effective mitigator compared to alpha-lipoic acid.


Asunto(s)
Traumatismos Experimentales por Radiación/tratamiento farmacológico , Protectores contra Radiación/uso terapéutico , Resveratrol/uso terapéutico , Ácido Tióctico/uso terapéutico , Animales , Colon/efectos de los fármacos , Colon/patología , Colon/efectos de la radiación , Duodeno/efectos de los fármacos , Duodeno/patología , Duodeno/efectos de la radiación , Rayos gamma/efectos adversos , Yeyuno/efectos de los fármacos , Yeyuno/patología , Yeyuno/efectos de la radiación , Masculino , Ratones , Traumatismos Experimentales por Radiación/patología , Irradiación Corporal Total/efectos adversos
19.
J Res Med Sci ; 14(3): 171-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-21772879

RESUMEN

BACKGROUND: There are few epidemiologic studies on vitamin D status of postmenopausal women in the Middle East countries. This study aimed to investigate the 25-hydroxyvitamin D levels in postmenopausal women living in the north-west of Iran. METHODS: Using the records of the local household registry, 300 cases were enrolled by simple random sampling. Serum 25-hydroxyvitamin D levels were determined by fully automated chemiluminescent immunoassay. In addition, the study included survey questions regarding age, body weight and height, use of supplements and skin protection agents and clinical and reproductive histories. RESULTS: Our cases had the mean age of 63.41 ± 4.64 years with menopause duration of 16.79 ± 6.15 years. Median and interquartile 25-75 range of vitamin D were 14.20 ng/ml and 7-37.2 ng/ml respectively. We found hypovitaminosis D [25(OH) D < 10 ng/ml] in 38.3% of our cases. Serum 25(OH) D concentrations were not significantly correlated with age or BMI. CONCLUSIONS: These findings indicate that 25(OH) D levels in postmenopausal women of north-west Iran are low. Studies to elucidate and assess the dietary intake of vitamin D in elderly women of this region can be of further benefit.

20.
Cell J ; 21(3): 236-242, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31210428

RESUMEN

OBJECTIVE: The Lung is one of the most radiosensitive organs of the body. The infiltration of macrophages and lymphocytes into the lung is mediated via the stimulation of T-helper 2 cytokines such as IL-4 and IL-13, which play a key role in the development of fibrosis. It is likely that these cytokines induce chronic oxidative damage and inflammation through the upregulation of Duox1 and Duox2, which can increase the risk of late effects of ionizing radiation (IR) such as fibrosis and carcinogenesis. In the present study, we aimed to evaluate the possible increase of IL-4 and IL-13 levels, as well as their downstream genes such as IL4ra1, IL13ra2, Duox1, and Duox2. MATERIALS AND METHODS: In this experimental animal study, male rats were divided into 4 groups: i. Control, ii. Melatonintreated, iii. Radiation, and iv. Melatonin (100 mg/kg) plus radiation. Rats were irradiated with 15 Gy 60Co gamma rays and then sacrificed after 67 days. The expressions of IL4ra1, IL13ra2, Duox1, and Duox2, as well as the levels of IL-4 and IL-13, were evaluated. The histopathological changes such as the infiltration of inflammatory cells, edema, and fibrosis were also examined. Moreover, the protective effect of melatonin on these parameters was also determined. RESULTS: Results showed a 1.5-fold increase in the level of IL-4, a 5-fold increase in the expression of IL4ra1, and a 3-fold increase in the expressions of Duox1 and Duox2. However, results showed no change for IL-13 and no detectable expression of IL13ra2. This was associated with increased infiltration of macrophages, lymphocytes, and mast cells. Melatonin treatment before irradiation completely reversed these changes. CONCLUSION: This study has shown the upregulation of IL-4-IL4ra1-Duox2 signaling pathway following lung irradiation. It is possible that melatonin protects against IR-induced lung injury via the downregulation of this pathway and attenuation of inflammatory cells infiltration.

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