strontium-radioisotopes and Necrosis

Among various types of ionizing radiation, the beta emitter radionuclides are involved in many sectors of human activity, such as nuclear medicine, nuclear industries and biomedicine, with a consequently increased risk of accidental, occupational or therapeutic exposure. Despite their recognized importance, there is little information about the effect of beta particles at the cellular level when compared to other types of ionizing radiation. Thus, the objective of the present study was to evaluate the genotoxic and cytotoxic effects of (90)Sr/(90)Y-a pure, highly energetic beta source-on Chinese hamster ovary (CHO) cells and to compare them with data obtained with (60)Co. CHO cells irradiated with different doses of (60)Co (0.34 Gy min(-1)) and (90)Sr/(90)Y (0.23 Gy min(-1)) were processed for analysis of clonogenic death, induction of micronuclei (MN) and interphase death. The survival curves obtained for both types of radiation were fitted by the exponential quadratic model and were found to be similar. Also, the cytogenetic results showed similar frequencies of radio-induced MN between gamma and beta radiations and the MN distribution pattern among cells did not follow the expected Poisson probability pattern. The relative variance values were significantly higher in cells irradiated with (90)Sr/(90)Y than with (60)Co in all exposure doses. The irradiated cells showed more necrotic cells 72 h and 96 h after exposure to beta than to gamma radiation. In general, the (90)Sr/(90)Y beta-radiation was more damaging than (60)Co gamma-rays. The data obtained also demonstrated the need to use several parameters for a better estimate of cellular sensitivity to the action of genotoxic agents, which would be important in terms of radiobiology, oncology and therapeutics.

Topics: Animals; Apoptosis; Beta Particles; CHO Cells; Cobalt Radioisotopes; Cricetinae; Dose-Response Relationship, Radiation; Female; Gamma Rays; Necrosis; Strontium Radioisotopes

Three patients with a choroidal melanoma, treated with HDR (High Dose Rate) Strontium-90 brachytherapy, underwent an enucleation. Radiation effect was only visible at the irradiation zone with a brisk transition to normal tissue. Tumour was replaced by necrotic and scar tissue. The underlying sclera had a markedly reduced number of fibrocytes, but no structural alteration of the collagen stroma.

Topics: Aged; Brachytherapy; Cell Count; Choroid; Choroid Neoplasms; Cicatrix; Collagen; Eye Enucleation; Female; Fibroblasts; Follow-Up Studies; Humans; Male; Melanoma; Middle Aged; Necrosis; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Radiopharmaceuticals; Radiotherapy Dosage; Sclera; Strontium Radioisotopes

Beta-radiation has been used since 1950 as a postoperative measure to reduce the recurrence of pterygia. Scleral necrosis has been a major complication after radiotherapy that has led to perforation of the globe, endophthalmitis, and visual loss in some cases.. A patient is presented in whom scleral necrosis developed 25 days after a pterygiectomy with bare sclera technique followed by 3000 cGy in 3 weekly, divided doses of strontium 90. After a conjunctival graft failure, the patient was treated with hyperbaric oxygen therapy.. The sclera revascularized and returned to nearly normal thickness after 14 sessions of hyperbaric oxygen therapy.. Hyperbaric oxygen therapy may be an effective treatment for acute scleral necrosis after postoperative beta-radiation.

Topics: Adult; Humans; Hyperbaric Oxygenation; Male; Necrosis; Pterygium; Radiation Injuries; Radiotherapy, Adjuvant; Sclera; Strontium Radioisotopes

Topics: Animals; Bone and Bones; Bone Plates; Dogs; Male; Methylmethacrylates; Necrosis; Osteotomy; Strontium Radioisotopes; Tibia; Tibial Fractures

Quantitative determination of the development of collateral arteries and change in portal flow after an 80 per cent dearterialization of the liver of the rabbit was carried out with radioactive microsphere technique. The livers operated upon were classified macroscopically into two type groups. In the recovery type, the dearterialized lobes reverted to the preoperative state. In the necrotic type, necrosis in the dearterialized lobe progressed, and the nonarterialized lobe was compensatively hypertrophied. The rate of rearterialization into the dearterialized lobe was different according to the type. In the recovery type, collateral arteries developed rapidly until the fourteenth postoperative day, when the arterial flow reached 55 per cent and, thereafter, increased gradually. In the necrotic type, rearterialization progressed more rapidly, and arterial flow exceeded the preoperative value in the third postoperative week and, thereafter, decreased. In the necrotic type, portal flow in the dearterialized lobe had been significantly impeded within 12 hours after the operation. The state of portal flow in the dearterialized lobe is, we believe, a more important factor for the prognosis after the hepatic dearterialization than the rate of rearterialization or oxygen concentration of portal blood. High activity of serum glutamic oxalacetic transaminase and serum glutamic pyruvic transaminase of more than 90 units per milliliter on the seventh postoperative day can be an indicator for the impeded portal flow in the dearterialized lobe.

Topics: Alanine Transaminase; Angiography; Animals; Aspartate Aminotransferases; Blood Flow Velocity; Cardiac Catheterization; Collateral Circulation; Female; Hemodynamics; Hepatic Artery; Hypertrophy; Ligation; Liver; Liver Circulation; Male; Microspheres; Necrosis; Rabbits; Strontium Radioisotopes

Topics: Bone and Bones; Bone Diseases; Calcium Radioisotopes; Diagnosis, Differential; Humans; Infections; Necrosis; Phosphorus Radioisotopes; Prostheses and Implants; Radioisotopes; Radionuclide Imaging; Strontium Isotopes; Strontium Radioisotopes

Sixty-seven hip joints with intracapsular fracture and the 67 opposite, normal hip joints were studied with 85Sr scintimetry from two weeks to six years after fracture. Consistently, fractures that developed osteonecrosis showed extremely high counts at the fracture site and the femoral head; fractures that failed to unite also showed extremely high counts at the fracture site and somewhat lower counts in the femoral head; fractures that were healing normally showed counts at the fracture site that were higher than those of the normal, uninjured hip but lower than those at fracture sites where osteonecrosis or nonunion was present. Prediction of complications by 85Sr scintimetry is not reliable within the first few months on injury; thereafter, however, the procedure has definite diagnostic value, particularly for osteonecrosis.

Topics: Adult; Aged; Bone Diseases; Fractures, Bone; Hip Injuries; Hip Joint; Humans; Middle Aged; Necrosis; Postoperative Complications; Radionuclide Imaging; Strontium Radioisotopes; Time Factors; Wound Healing

Topics: Evaluation Studies as Topic; Female; Femoral Fractures; Femur Head Necrosis; Fluorine; Hip Joint; Humans; Injections, Intravenous; Joint Diseases; Knee Joint; Middle Aged; Necrosis; Oscillometry; Osteoarthritis; Radionuclide Imaging; Strontium Radioisotopes; Time Factors

Topics: Adolescent; Adult; Chronic Disease; Diagnosis, Differential; Fascia; Fasciotomy; Female; Fractures, Bone; Humans; Ischemia; Leg; Leg Injuries; Male; Muscular Diseases; Necrosis; Pain; Physical Exertion; Sports Medicine; Strontium Radioisotopes

Topics: Adrenal Cortex Hormones; Adult; Bone Diseases; Citrates; Female; Humans; Kidney Transplantation; Male; Middle Aged; Necrosis; Phosphates; Radiography; Radionuclide Imaging; Strontium Radioisotopes; Technetium; Transplantation, Homologous

Topics: Bone Diseases; Cartilage, Articular; Curettage; Humans; Necrosis; Osteotomy; Radiography; Radionuclide Imaging; Strontium Radioisotopes; Tibia

Topics: Age Factors; Bone and Bones; Bone Diseases; Bone Neoplasms; Calcification, Physiologic; Fluorine; Fractures, Bone; Humans; Infections; Necrosis; Neoplasm Metastasis; Osteitis; Radioisotopes; Radionuclide Imaging; Regional Blood Flow; Sclerosis; Strontium Radioisotopes; Technetium; Time Factors; Whole-Body Counting

Topics: Aged; Antineoplastic Agents; Bone Diseases; Cortisone; Female; Hip Dislocation, Congenital; Humans; Ischemia; Knee; Leg Length Inequality; Male; Necrosis; Polyneuropathies; Radiography; Radionuclide Imaging; Strontium Radioisotopes