The applications of three dimensional conformal radiotherapy(3-DCRT)in the abdomen has been associated with the increased incidence of radiation-induced liver injury(RILI). Timely and appropriate evaluation of RILI is particularly important for the design and modification of clinical management of tumors. This article reviews the pathological and serological features of RILI, focusing on in the application of medical imaging.
Diagnostic Imaging ; Humans ; Liver ; radiation effects ; Liver Diseases ; Radiation Injuries ; diagnosis ; Radiotherapy, Conformal

OBJECTIVETo study the effects of extremely low frequency electromagnetic fields (ELF EMFs) on apoptosis and cell cycle of mouse brain and liver cells.

METHODSMice were exposed to 50 Hz, 0.2 mT or 6.0 mT electromagnetic fields for 2 weeks. TUNEL and flow cytometric methods were used to analyze apoptosis and cell cycle of brain and liver cells.

RESULTSAfter exposure to 0.2 mT and 6.0 mT ELF EMFs for 2 weeks, apoptosis rates of brain cells [(5.60 +/- 1.47)% and (4.73 +/- 0.48)% respectively] were higher than that of control [(2.90 +/- 0.75)%], and apoptosis rates of liver cells [(4.19 +/- 2.08)% and (3.38 +/- 0.65)% respectively] were higher than that of control [(1.84 +/- 0.76)%]. G0/G1 cell percentage of brain cells [(80.21 +/- 1.68)% and (79.54 +/- 0.56)% respectively] were higher than that of control [(76.85 +/- 0.83)%], and those of liver cells [(79.42 +/- 1.80)% and (80.47 +/- 1.79)% respectively] were higher than that of control [(73.36 +/- 3.10)%]. The above differences were all statistically significant as P < 0.05. At the same time S and G2 + M cell percentage of brain and liver cells were significantly decreased.

CONCLUSIONExposure to 50 Hz EMFs may alter cell cycle and induce apoptosis of mouse brain and liver cells.

Animals ; Apoptosis ; radiation effects ; Brain ; cytology ; radiation effects ; Cell Cycle ; radiation effects ; Electromagnetic Fields ; Flow Cytometry ; In Situ Nick-End Labeling ; Liver ; cytology ; radiation effects ; Male ; Mice

OBJECTIVETo study the effects of intense electromagnetic pulse(EMP) on the biological effects of mitochondrial membrane.

METHODRat liver mitochondrial suspension was exposed to EMP at 60 kV/m level. The changes of membrane lipid fluidity and membrane protein mobility were detected by ESR and spin label technique. Malondialdehyde(MDA) was detected by spectrophotometer.

RESULTSThe mobility of membrane protein decreased significantly(P < 0.05). Correlation time (tau c) of control group was (0.501 +/- 0.077) x 10(-9)s, and tau c of EMP group was (0.594 +/- 0.049) x 10(-9)s, indicating that the mobility of protein was restricted. The fluidity of mitochondrial membrane increased significantly(P < 0.05) at the same time. Order parameter(S) of mitochondrial membrane lipid in control group was 0.63 +/- 0.01, while S of EMP group was 0.61 +/- 0.01(P < 0.05). MDA decreased significantly.

CONCLUSIONThe mobility and lipid peroxidation of mitochondrial membrane may be disturbed after EMP exposure.

Animals ; Electromagnetic Phenomena ; Lipid Peroxidation ; radiation effects ; Membrane Fluidity ; radiation effects ; Mitochondria, Liver ; metabolism ; radiation effects ; Mitochondrial Membranes ; metabolism ; radiation effects ; Rats

Emerging concerns regarding the hazard from medical radiation including CT examinations has been suggested. The purpose of this study was to observe the longitudinal changes of CT radiation doses of various CT protocols and to estimate the long-term efforts of supervising radiologists to reduce medical radiation. Radiation dose data from 11 representative CT protocols were collected from 12 hospitals. Attending radiologists had collected CT radiation dose data in two time points, 2007 and 2010. They collected the volume CT dose index (CTDIvol) of each phase, number of phases, dose length product (DLP) of each phase, and types of scanned CT machines. From the collected data, total DLP and effective dose (ED) were calculated. CTDIvol, total DLP, and ED of 2007 and 2010 were compared according to CT protocols, CT machine type, and hospital. During the three years, CTDIvol had significantly decreased, except for dynamic CT of the liver. Total DLP and ED were significantly decreased in all 11 protocols. The decrement was more evident in newer CT scanners. However, there was substantial variability of changes of ED during the three years according to hospitals. Although there was variability according to protocols, machines, and hospital, CT radiation doses were decreased during the 3 years. This study showed the effects of decreased CT radiation dose by efforts of radiologists and medical society.
Abdomen/radiation effects ; Angiography ; Brain/radiation effects ; Female ; Hospitals ; Humans ; Liver/radiation effects ; Longitudinal Studies ; Male ; Middle Aged ; *Radiation Dosage ; *Tomography, X-Ray Computed/instrumentation

OBJECTIVETo study the effects of extremely low frequency electromagnetic field(ELF EMF) and its combination with lead on the antioxidant system in mouse brain and liver tissues.

METHODMice were exposed to a 50 Hz sinusoidal 0.2 mT or 6.0 mT EMF for 2 weeks. At the same time, some groups were exposed to lead(50 mg/kg). After the exposure, the antioxidant system and cell membrane fluidity in brain and liver were measured.

RESULTSMalondiadehyde(MDA) content in brain and liver increased from the control levels of (1.33 +/- 0.12) and (3.95 +/- 0.21) nmol/mg pro to (1.35 +/- 0.09) and (6.15 +/- 0.28) nmol/mg pro respectively following 0.2 mT exposure, and to (3.98 +/- 0.10) and (6.50 +/- 0.79) nmol/mg pro respectively following 6.0 mT exposure. Total antioxidant capability(T-AOC) in brain and liver decreased from the control levels of (4.39 +/- 0.48) and (2.45 +/- 0.21) U/mg pro to (3.99 +/- 0.39) and (1.92 +/- 0.32) U/mg pro respectively following 0.2 mT, and to (3.12 +/- 0.37) and (1.57 +/- 0.14) U/mg pro respectively following 6.0 mT. GSH content decreased only in liver tissue from the control level of (194.60 +/- 20.93) mg/g pro to (189.24 +/- 5.61) mg/g pro(0.2 mT) and (153.04 +/- 1.18) mg/g pro(6.0 mT). Cellular membrane fluidity decreased from the control levels of (1.396 +/- 0.040) and (2.899 +/- 0.552) to (1.224 +/- 0.190) and (1.894 +/- 0.0761) (0.2 mT), (1.159 +/- 0.179) and (1.516 +/- 0.204)(6.0 mT) respectively. Compared with single EMF exposure(6.0 mT), EMF combined with lead exposure induced remarkable increase in MDA, GSH content and T-AOC and decrease in cell membrane fluidity both in the brain and liver, and increase in SOD activity only in liver.

CONCLUSIONELF EMF might alter the metabolism of free radicals, decrease anti-oxidant capability and enhance lipid peroxidation. The combination of EMF with lead showed synergic effects on lipid peroxidation.

Animals ; Antioxidants ; metabolism ; Brain ; drug effects ; metabolism ; radiation effects ; Electromagnetic Fields ; adverse effects ; Glutathione ; analysis ; Lead ; toxicity ; Lipid Peroxidation ; drug effects ; radiation effects ; Liver ; drug effects ; metabolism ; radiation effects ; Membrane Fluidity ; drug effects ; radiation effects ; Mice ; Superoxide Dismutase ; metabolism

It is a difficult problem in high intensity focused ultrasound (HIFU) therapeutic dosimetry that how to use a BFR to ablate a mass in tissue and to determine the energy-efficiency relation, that is, the scale of biological effects of HIFU. A mass lesion was realized in this study according to a treatment principle of damaging tissue from BFRs to fascicle lesions, slice lesions and a mass lesion. A 1.6 MHz transducer, 150 mm in diameter and with a focal length of 120 mm, was used. The focal intensities (I(SATA)) were 0-27 000 W/cm2 and the scanning speeds were 1-4 mm/s. The distance between every fascicle lesion was 5-10 mm and the distance between two slice lesions was 10-20 mm. Different irradiation depths of fascicle slice and mass lesion were observed after HIFU procedures in this study. The dosage of HIFU required for tissue coagulated necrosis was evaluated with energy of HIFU (J) per cubic millimeter (mm3), i.e., J/mm3 which was defined as energy-efficiency factor (EEF). Results showed that EEF needed for producing fascicle lesions increased with the increase of irradiation depth. EEF required for inducing various lesions in biological tissue was different. Generally, it followed the law: EEF(mase)< EEF(slice) Animals ; Cattle ; In Vitro Techniques ; Liver ; pathology ; radiation effects ; Radiation Dosage ; Time Factors ; Ultrasonic Therapy ; methods

This study was aimed at exploring the high intensity focused ultrasound(HIFU) therapeutic dosimetry and its biologic effect. In-vitro, bovine liver was immersed into 0.9% NS and degassed for application. The JC Model-focused ultrasound tumor therapeutic system was used in the experiment. The HIFU parameters were: frequency 1.6 MHz, depth 20 mm, acoustic power from 16.44 W to 196.32 W. Under each power, at radiating times from is to 20 s, bioptic specimens were obtained from all samples. The results showed when the acoustic power was equal to or higher than 179.96 W, only is of radiating is adequate to induce coagulative necrosis, and when the acoustic power was lower than 65.44 W, the radiating time to produce coagulative necrosis was about 7 s. In the range of 65.44-179.96 W, at each time when the acoustic power was set up with an increment of 16.36 W, the time to produce coagulative necrosis was 1-2 s shorter. The form of biological focal region (BFR) varied with the acoustic power and HIFU irradiation time. The size of BFR increased with the increase of HIFU irradiation dosage (acoustic power x exposure time). There is positive correlation between the size of BFR and the dosage of HIFU irradiation (y = 0.0164x(1.05591), R5 = 0.9238, P < 0.05).
Animals ; Cattle ; In Vitro Techniques ; Liver ; pathology ; radiation effects ; Radiation Dosage ; Ultrasonic Therapy ; instrumentation ; Ultrasonics

To establish an in vivo radiation carcinogenesis model using glutathione S-transferase placental form positive (GST-P+) hepatic foci, newborn rats were irradiated once by 0.5 Gy and 2 Gy of gamma ray or 0.15 Gy and 0.6 Gy of neutron with or without 0.05% phenobarbital (PB). When the rats were sacrificed at the 12th or 21st week, the incidence of GST-P+ foci induction by radiation alone was very low. The neutron was more sensitive than the gamma ray at week 12 and the reverse phenomenon was observed in the groups at week 21. PB combination showed an increased incidence of GST-P+ foci in gamma ray irradiated groups. The neutron irradiation combined with PB did not show any significant difference compared with the corresponding PB untreated groups. We also investigated the combined effect of diethylnitrosamine (DEN) and 0.75 Gy of gamma ray irradiation. Intraperitoneal injection of 0.15 mumol/g body weight of DEN at 1 hour after gamma ray irradiation showed significantly increased the number and area of GST-P+ foci compared with those of DEN alone or DEN at 1 hour before gamma radiation (P < 0.001). From these data, after more defined experiments, an in vivo radiation carcinogenesis model will be established by radiation alone or a combination of radiation and carcinogens.
Animal ; Body Weight ; Diethylnitrosamine/*adverse effects ; Female ; Gamma Rays/adverse effects ; Glutathione Transferase/*drug effects/*radiation effects ; Liver/*drug effects/pathology/*radiation effects ; Liver Neoplasms/epidemiology/*etiology/pathology ; Neoplasms, Radiation-Induced/epidemiology/*etiology/pathology ; Neutrons/adverse effects ; Organ Weight ; Phenobarbital/*adverse effects ; Placenta/drug effects/radiation effects ; Pregnancy ; Radiation Dosage ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVETo study the impacts of exposure to electromagnetic radiation (EMR) on liver function in rats.

METHODSTwenty adult male Sprague-Dawley rats were randomly divided into normal group and radiated group. The rats in normal group were not radiated, those in radiated group were exposed to EMR 4 h/ d for 18 consecutive days. Rats were sacrificed immediately after the end of the experiment. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and those of malondialdehyde (MDA) and glutathione (GSH) in liver tissue were evaluated by colorimetric method. The liver histopathological changes were observed by hematoxylin and eosin staining and the protein expression of bax and bcl- 2 in liver tissue were detected by immunohistochemical method. Terminal-deoxynucleotidyl transferase mediated nick and labelling (TUNEL) method was used for analysis of apoptosis in liver.

RESULTSCompared with the normal rats, the serum levels of ALT and AST in the radiated group had no obvious changes (P>0.05), while the contents of MDA increased (P < 0.01) and those of GSH decreased (P < 0.01) in liver tissues. The histopathology examination showed diffuse hepatocyte swelling and vacuolation, small pieces and focal necrosis. The immunohistochemical results displayed that the expression of the bax protein was higher and that of bcl-2 protein was lower in radiated group. The hepatocyte apoptosis rates in radiated group was higher than that in normal group (all P < 0.01).

CONCLUSIONThe exposure to 900 MHz mobile phone 4 h/d for 18 days could induce the liver histological changes, which may be partly due to the apoptosis and oxidative stress induced in liver tissue by electromagnetic radiation.

Animals ; Apoptosis ; Cell Phone ; Electromagnetic Radiation ; Liver ; pathology ; radiation effects ; Male ; Oxidative Stress ; Proteomics ; Rats ; Rats, Sprague-Dawley ; Staining and Labeling

OBJECTIVETo study the effect of radiation injury on nitric oxide (NO) concentration in mouse peripheral blood and liver.

METHODSNIH mice were subjected to gamma-ray exposure at 9.0 Gy and transferred immediately in room temperature condition. NO concentrations in the liver and peripheral blood were examined before and at different time points after the exposure.

RESULTSCompared to that before exposure, NO concentration in the peripheral blood and liver significantly increased after gamma-ray exposure. NO concentration in the peripheral blood began to increase 3 h after the exposure, but that in the liver increased till 6 h after the exposure.

CONCLUSIONRadiation can cause the increase of NO concentration in the peripheral blood and liver, but different tissues may exhibit different response intensities to radiation.

Animals ; Gamma Rays ; Liver ; metabolism ; radiation effects ; Male ; Mice ; Nitric Oxide ; blood ; metabolism ; Radiation Injuries, Experimental ; blood ; metabolism ; Time Factors