Fabrication of cesium-137 brachytherapy sources using vitrification technology.

137Cs source in solid matrix encapsulated in stainless-steel at MBq (mCi) levels are widely used as brachytherapy sources for the treatment of carcinoma of cervix uteri. This article describes the large-scale preparation of such sources. The process of fabrication includes vitrification of 137Cs-sodium borosilicate glass, its transformation into spheres of 5-6 mm diameter, casting of glass spheres into a cylinder of 1.5 mm (varphi) x 80 mm (l) in a platinum mould, cutting of the moulds into 5-mm-long pieces, silver coating on the sources, and finally, encapsulation in stainless steel capsules. Development of safety precautions used to trap 137Cs escaping during borosilicate glass preparation is also described. The leach rates of the radioactive sources prepared by the above technology were within permissible limits, and the sources could be used for encapsulation in stainless steel capsules and supplied for brachytherapy applications. This development was aimed at promoting the potential utility of 137Cs-brachytherapy sources in the country and reducing the user's reliance on imported sources. Since its development, more than 1000 such sources have been made by using 4.66 TBq(126 Ci) of 137Cs.

Recovery and purification of 4.66 TBq(126Ci) of 137Cs from a 20-year-old spent sealed source.

An attempt to recover and purify 4.66 TBq(126Ci) of (137)Cs as solution from a 20-year-old doubly encapsulated sealed source containing (137)CsCl was made successfully. The primary capsule was first cut open to retrieve the secondary capsule. The top end of the secondary SS capsule was then cut to render it as an open cylinder and the (137)CsCl pellet inside was dissolved in small aliquots of water. Each aliquot of the (137)CsCl solution was dispensed into glass vials, sealed, assayed and stored. Barium formed during the radioactive decay of (137)Cs was removed by carbonate precipitation. Chloride was removed by heating with HNO(3) and evaporation. About 91.8% of the total activity could be recovered and used subsequently for making brachytherapy sources.

A double-blind clinical trial comparing the gastrointestinal side effects of two enteral feeding formulas.

Adequate enteral nutritional support is often limited by gastrointestinal (GI) side effects. In this pilot clinical trial we compared an enteral nutrition formula based on soy hydrolysate (study formula, SF) against a widely used intact casein formula (control formula, CF) for the incidence of GI side effects in a completely randomized double blind design. Twenty-three nonsurgical hospitalized patients requiring enteral nutritional support and free of GI symptoms were randomly assigned to receive either the CF or the SF for 6 days continuously. Both formulas were isotonic, low in residue, lactose free and isocaloric, but differed in the type and concentration of protein and the concentration of medium-chain triglycerides. After randomization both groups were comparable in demographic characteristics, and nutritional status, but there were more patients on antibiotics in the CF group. The amount of formula infused per day and the route of administration were equivalent. The number of bowel movements per day was 1.0 +/- 0.5 for the CF group and 0.6 +/- 0.3 for the SF group (p less than 0.05). The incidence of diarrhea was 10.8% days for the CF group and 6.2% for the SF group (p = NS). High gastric residuals occurred in 16.9% of days in the CF group and 3.3% in the SF group (p less than 0.05). Vomiting incidence was 10.8% in the CF group and 1.5% in the SF group (p less than 0.05). After adjustment for the use of antibiotics as a covariate, the differences in number of bowel movements, vomiting and incidence of high residuals became less significant (p less than 0.10).(ABSTRACT TRUNCATED AT 250 WORDS)

Depressed erythrocyte glutathione reductase activity in sickle cell disease.

In a group of 27 sickle cell disease patients ranging in age from 2 yr 3 months to 43 yr, 13 (48%) were found to have depressed erythrocyte glutathione reductase activity suggesting riboflavin deficiency. Glutathione reductase activity coefficients did not correlate with riboflavin intakes which were calculated from 3-day diet records returned by 16 patients. Other causes of riboflavin deficiency including decreased absorption, altered metabolism, or increased excretion of the vitamin must be considered. The potential effect of depressed erythrocyte glutathione reductase activity in the sickle cell disease process is discussed.