A practical profile of integrated safety assessment of near-surface disposal of radwaste at PINSTECH.

Near-surface or shallow land disposal of radioactive waste has been the primary practice at the Pakistan Institute of Nuclear Science and Technology (PINSTECH). The adopted choice of this mode of disposal has been based on a study of the site and the quality and quantity of waste generated at the 5 MW reactor with HEU fuel. Specific measures regarding the radiation safety of the workers and environmental protection have been adopted. The waste disposal operations are conducted to meet local regulatory requirements, IAEA recommendations and internationally endorsed principles such as ALARA (as low as reasonably achievable - economic, social and other relevant factors being considered). The data obtained through the years of operational and management experience have manifested the robustness of the disposal system and reliability of the disposal criterion, and have also served to further refine the latter. Consequently, confidence in the current shallow-land-burial practices has increased. Radiological safety of these practices has been assessed by addressing different aspects of the safety and disposal system. These parameters, as indices of a non-exclusive and operational safety model, are presented.     

Hearing acuity in post spinal analgesia period

100 cases of either sex 96 males and 4 females in their mean age group of 45 year ± 14.51 standard deviation were selected for this study to analyse the Hearing Acuity in the post spinal analgesia period during a period of eight months in the E.N.T department of the J.N. Medical College A.M.U. Aligarh. The size of the needle used for spinal analgesia was 22G and the equipment for Audiometry was the pure tone Audiometer. Pure tone Audiometry was done pre-operatively and then on the 1st, 3rd, 5th and 12th subsequent post-operative days and then after six months. It was found that 12% of the patients showed incidence of mild hearing loss. However, the loss was transient, reversible, within low frequency range (250, 500, 1000 Hz), and no patient suffered from any permanent hearing loss.     

Diminution in Kerosene-Mediated Induction of Drug Metabolizing Enzymes by Asbestos in Rat Lungs

Abstract: In order to determine the pulmonary toxicity of kerosene and its ignition product (soot) in asbestos exposed subjects, the activities of phase I and phase II drug metabolizing enzymes in rat lungs after single intratracheal coexposure to Indian chrysotile asbestos and kerosene or its soot and Indian chrysotile were assayed. Exposure to kerosene or its soot resulted in a significant increase in the level of microsomal cytochrome P-450 and the activity of P-450 dependent monooxygenase, benzo(a)pyrene hydroxylase, as well as in the activities of microsomal epoxide hydrase and cytosolic glutathione-S-transferase (GST). However, in chrysotile exposed animals a reverse pattern in these parameters was recorded. The co-exposure to chrysotile and kerosene or chrysotile and soot led to a significant depletion in cytochrome P-450 level and a decrease in the activities of benzo(a)pyrene hydroxylase, epoxide hydrase and GST when compared to kerosene and soot controls, respectively. These results suggest that asbestos by altering the pulmonary drug metabolizing enzyme system may increase the toxic potential of kerosene and its ignition product in the respiratory system.     

Microscooter injuries in the paediatric population.

OBJECTIVES: To illustrate the types of injuries seen by the accident and emergency department as a result of the use of non-motorized 'microscooters' in children, and to increase awareness of scooter-related triplane fractures of the ankle. STUDY DESIGN: A retrospective study conducted in an accident and emergency department of a district general hospital on all children who had a scooter-related limb injury over a 6-month period and were referred for orthopaedic review. METHODS: The analysis involved a case note review. Information recorded included the injury sustained, protective equipment worn at the time of the accident and management by the orthopaedic team. RESULTS: Scooter injuries accounted for 10 fractures in this period. There were three 'triplanar' injuries, which required operative fixation, and three injuries requiring manipulation under anaesthesia. No protective gear was worn by any of the patients. CONCLUSION: The popularity of microscooters seems to represent a significant risk of bony injury in the paediatric population. Medical personnel who manage acute paediatric trauma should be aware of scooter-related triplanar ankle injuries.     

Uptake of technetium 99m MDP by hepatoblastoma

Focal uptake of ^99mTc-MDP was seen in a case of hepatoblastoma. The focal uptake corresponded to an area of calcification on CT, which was shown histologically to consist of osteoid with mineralization. The mechanism of uptake by the tumor in this case is likely to be the same as for skeletal uptake.     

Practical miniaturized membrane oxygenator for isolated organ perfusion

Silastic membrane tubing oxygenators possess valuable atraumatic properties, but no satisfactory miniature system for isolated organ perfusion has been achieved. We describe the construction of a new type of miniaturized Silastic membrane tubing oxygenator, 1.5 m long, 1.5-mm diameter, 75-micron wall thickness, incorporated in a single self-supporting unit readily applicable to isolated organ perfusion because of its simplicity, durability, and small prime volume of less than 3 ml. In vitro experiments using out-dated human banked blood demonstrated that the unit can effectively oxygenate blood of hematocrit 35% at flow rates of at least 10 ml/minute and that higher flow rates may be used to oxygenate blood or perfusates of a lower hematocrit. The results were verified in three different practical experimental applications: isolated rat liver, rabbit heart, and rat free skin flap perfusion.