OBJECTIVES To evaluate residual disease in uterine cervical cancer patients treated with teletherapy using combined high dose rate Cobalt-60 brachytherapy. MATERIALS AND METHODS A retrospective study of uterine cervical cancer patients, FIGO stages IB-IVB (International Federation of Gynecologists and Obstetricians recommendations), treated by radiotherapy alone between April 1986 and Decembe...

This study examines the effect of routine gamma radiation based on cobalt 60 on the viability, mosquito larvicidal activity, and density of bacillus spores in the soil. Although 1 g of unirradiated powder of Bacillus thuringiensis israelensis (Bti) contains on average 6.2 x 10(9) spores, no spores survived radiation doses of 20.6 kGy and higher. Radiation at a dose of 20-25 kGy caused a 20-30% ...

PURPOSE: Collision detection for external beam radiation therapy (RT) is important for eliminating the need for dryruns that aim to ensure patient safety. Commercial treatment planning systems (TPS) offer this feature but they are expensive and proprietary. Cobalt-60 RT machines are a viable solution to RT practice in low-budget scenarios. However, such clinics are hesitant to invest in these m...

Pineal gland has and antistressogenic role. Its main hormone, melatonin, has radio protective effect on endocrine and other dynamic tissues. In our previous study, we have shown that pinealectomy changes the behavior of suprarenal gland in totally irradiated rats. The aim of this study is to evaluate the effect of exogenous melatonin on suprarenal gland of rats with or without pineal gland. Fou...

We report a radiation accident in whlch a technologist was in close proximlty for 40 seconds to a source containing 7,700 curies of cobalt 60. The average bone marrow dose was estlmated at 118 rads. Within the first 24 hours postexposure, lymphopenla developed and after two weeks, the platelet and granulocyte count began to fall and reached nadir at approximately four weeks. During the phase of...

Endotracheal metastasis is a rare situation, usually associated with malignancies of breast and gastrointestinal tract, specially colon. Papillary carcinoma of thyroid commonly disseminates through lymphatic channels and tracheal involvement through vascular route is rarely reported. Here, we report a case of tracheal metastasis from papillary carcinoma of thyroid. The patient responded to exte...

Background: Cobalt (Co) is an essential trace element for mammals required for the synthesis of vitamin B12. It is not a cumulative toxin but chronic exposure induces negative effects on the organism. It was proven that cobalt passes via placenta appearing in the fetal blood and amniotic fluid and it is shown to possess an embryotoxic effect. Also, chromium (Cr) is recognized as a trace element...

Circular dichroism and difference ultraviolet visible spectra were obtained for cobalt hemoglobin derivatives. At 287 nm the ellipticity difference between the oxy- and deoxycobaltohemoglobin is about one-half as great as that for the native proteins indicating smaller quaternary conformational changes for the former. Deoxygenation increases the Soret rotational strengths of both iron and cobal...

background: hydrogen peroxide (h2o2), produced by gamma ray irradiation to watery solution, was used as an analytical parameter for dosimetry of cobalt-60 (60co) radiation. materials and methods: detection of the produced h2o2 was carried out using two methods: an amperometric biosensor fabricated by immobilization of anthraquinone 2-carboxylic acid modified horseradish peroxidase on glassy car...

introduction: this study was designed to evaluate dosimetric parameters such as rectal dose, bladder dose, integral dose (id), homogeneity index (hi) and conformity index (ci) in various treatment plans for prostate cancer. materials and methods: pelvic computed tomography (ct) scans of 27 patients were acquired and transferred to the rtdoseplan treatment planning system. for each patient, 8 co...