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OBJECTIVES: Our study aimed to apply the apparent diffusion coefficient (ADC) values to quantify the differences between low- and high-grade glioma tumors. METHODS: We conducted a multicenter, retrospective study between September to December 2019. Magnetic resonance imaging (MRI) diffusion-weighted images (DWIs), and the pathologic findings of 56 patients with glioma tumors (low grade = 28 and high grade = 28) were assessed to measure the ADC values in the tumor center, tumor edema, boundary area between tumor with normal tissue, and inside the healthy hemisphere. These values were compared between the two groups, and cut-off values were calculated using the receiver operating characteristic curve. RESULTS: We saw significant differences between the mean ADC values measured in the tumor center and edema between high- and low-grade tumors (p< 0.005). The ADC values in the boundary area between tumors with normal tissue and inside healthy hemisphere did not significantly differ in the groups. The ADC values at tumor center and edema were higher than 1.12 × 10-3 mm2/s (sensitivity = 100% and specificity = 96.0%) and 1.15 × 10-3 mm2/s (sensitivity = 75.0% and specificity = 64.0%), respectively, could be classified as low-grade tumors. CONCLUSIONS: The ADC values from the MRI DWIs in the tumor center and edema could be used as an appropriate method for investigating the differences between low- and high-grade glioma tumors. The ADC values in the boundary area and healthy tissues had no diagnostic values in grading the glioma tumors.
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This study aimed to introduce a new method for eye lens thermo-luminescent dosimetry and also estimate the dose associated with induced cancer risk due to the ionizing radiation exposure received by physicians and other staff cooperating in interventional cardiology (IC) procedures. The measurements were performed with six TLDs (thermoluminescent dosimeters): four TLDs for eye lens dosimetry (2 positioned on respiratory/surgical mask under the eye region as the new method; and 2 near the outside border of the eye as the common method) and two TLDs for whole-body dosimetry. Whole-body doses were used to calculate the cancer risks induced by IC procedures. The results of the new proposed method for eye lens dosimetry were similar to common TLD positioning (mean differences <5%) and mask displacement had no significant effect on eye dose measurement in our new method. Our proposed method for eye lens dosimetry is simpler and more comfortable compared to the common method and it can be used as an alternative method without using TLD holders to monitor lens dose for IC workers wearing masks during the procedure. The estimated excess cancer incidence risk induced by IC procedures was 29.58 ± 5.71 and 46.68 ± 7.77 (per 100000 individuals) for men and women, respectively.
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Measurement of background radiations (BRs) as the sources of cancer risk, is important. The aim of this study was to measure the BR, as well as its cancer risk and mortalities in Kohgiluyeh and Boyer-Ahmad province (KBAp). Indoors and outdoors BRs were measured in eight cities utilizing a Geiger-Muller detector. Five main locations (north, east, west, south, and center) were chosen for measuring outdoor and indoor BRs in each city of KBAp. The BEIR VII-Phase 2 model was used to calculate the BRs induced cancer risks and mortalities of various cancer types at different ages. The average dose rates of outdoor and indoor were 136.9⯱â¯12.5 and 149.3⯱â¯19.8 nSv.h-1, respectively. The average annual effective doses (AEDs) for adults, children, and infants were 0.17, 0.19, and 0.22 mSv.y-1 due to the outdoor, and 0.73, 0.84, and 0.94 mSv.y-1 resulting from the indoor exposure, respectively. The average lifetime risk for one year BRs induced cancers was 164.8⯱â¯15.7 and 307.1⯱â¯32.3 (in 100,000 people) for new-borns male and female, in that order. This risk decreased with age and reached 11.2⯱â¯1.6 and 13.8⯱â¯1.6 (in 100,000 people) for men and women at the age of 80, respectively. The average lifetime risk of mortality due to cancers induced by annual BRs was 70.7⯱â¯8.3 and 113.8⯱â¯10.6 (incidence probability in 100,000 people) for new-borns male and female respectively. This risk decreased with age and reached 9.8⯱â¯1.3 and 12.2⯱â¯1.3 (in 100,000 people) for men and women at the age of 80 years, respectively.
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INTRODUCTION: Ionizing radiations induce damage to the bone marrow and blood cells. The aim of this study was to investigate the radioprotective effect of sesamol oral consumption on mice bone marrow and peripheral blood cells using micronuclei and alkaline comet assay. MATERIALS AND METHODS: This experimental-quantitative study was performed on 50 mice in 5 equal groups. One group received 50 mg/kg of sesamol for 7 consecutive days and another group received 100 mg/kg of this extract 2 h before irradiation (3 Gy gamma-rays of Cobalt-60). Irradiation without consuming sesamol and sesamol without irradiation were applied in other groups. Micronucleus and alkaline comet assays were used to measure the DNA damages in bone marrow and peripheral blood cells. The data were statistically compared using one-way ANOVA, and Tukey HSD test. RESULTS: In comparison with the only-irradiated group, oral consumption of sesamol 2 h and 7 days before irradiation decreased remarkably micro-nucleated normochromatid erythrocytes (mnNCE) as 54.5% and 70.4% (P < 0.0001), and micro-nucleated nucleated polychromatid erythrocytes (mnPCE) as 49% and 66% (P < 0.001), respectively. Furthermore, the number of PCE/NCE ratio increased as 47% and 83.6% (P < 0.0001) compared to the irradiated group. The percentage of DNA in tail and apoptotic comets decreased significantly with oral consumption of sesamol (daily or single dose) compared to the irradiated group (P < 0.005). These variations were greater in 7-day continuous pre-irradiation method. CONCLUSION: Sesamol as a radioprotector can reduce the effects of gamma irradiation on mice bone marrow and blood cells. The daily oral consumption of this extract is more effective in comparison with the single consumption before irradiation.
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Benzodioxoles/administración & dosificación , Ensayo Cometa , Rayos gamma , Pruebas de Micronúcleos , Fenoles/administración & dosificación , Protectores contra Radiación/administración & dosificación , Administración Oral , Animales , Células Sanguíneas/efectos de los fármacos , Médula Ósea/efectos de los fármacos , RatonesRESUMEN
BACKGROUND: Over the past several years our laboratories have investigated different aspects of the challenging issue of the alterations in bacterial susceptibility to antibiotics induced by physical stresses. OBJECTIVE: To explore the bacterial susceptibility to antibiotics in samples of Salmonella enterica subsp. enterica serovar Typhimurium (S. typhimurium), Staphylococcus aureus, and Klebsiella pneumoniae after exposure to gamma radiation emitted from the soil samples taken from the high background radiation areas of Ramsar, northern Iran. METHODS: Standard Kirby-Bauer test, which evaluates the size of the zone of inhibition as an indicator of the susceptibility of different bacteria to antibiotics, was used in this study. RESULTS: The maximum alteration of the diameter of inhibition zone was found for K. pneumoniae when tested for ciprofloxacin. In this case, the mean diameter of no growth zone in non-irradiated control samples of K. pneumoniae was 20.3 (SD 0.6) mm; it was 14.7 (SD 0.6) mm in irradiated samples. On the other hand, the minimum changes in the diameter of inhibition zone were found for S. typhimurium and S. aureus when these bacteria were tested for nitrofurantoin and cephalexin, respectively. CONCLUSION: Gamma rays were capable of making significant alterations in bacterial susceptibility to antibiotics. It can be hypothesized that high levels of natural background radiation can induce adaptive phenomena that help microorganisms better cope with lethal effects of antibiotics.