Plutonium distribution and oxidation states in a reactor leaching ponds system.

Concentrations of 239,240Pu and 238Pu in water, net plankton (algal material), suspended particulates and sediment, as well as Pu oxidation states in filtered water, were determined in a test reactor leaching ponds system in southeastern Idaho. The highest Pu concentration in the ponds system was found in net plankton, and concentrations varied significantly between sampling dates. Plutonium Concentration Ratios (CR) for plankton ranged from 3 X 10(4) to 4 X 10(5). The lowest Pu concentration was found in filtered water, primarily because of the absence of complexing agents. The majority of Pu in filtered water was in true solution (60-87%) or present in colloidal particles smaller than 0.22 micron. Plutonium association with sediment was inversely related to particle size. The "environmental" distribution coefficients (Kd) for Pu ranged from 1.6 X 10(4) to 1.2 X 10(5) reflecting the importance of sediments as the main reservoir for Pu in the ponds system. No significant differences were noted between CR or Kd values for 239,240Pu and 238Pu. The reduced Pu oxidation states (III and IV) fractions ranged from 57% to 71% of the total dissolved Pu in water. This is in contrast with oxidation states distribution from other large aquatic systems (Great Lakes and the Irish Sea) where Pu is predominately in oxidized (V and VI) forms.

A defense in depth approach to radiation protection for 125I production activities.

Not all operational radiation protection situations lend themselves to simple solutions. Often a Radiation Protection Program must be developed and implemented for difficult situations. A defense in depth approach to radiation protection was developed for 125I production activities. Defense in depth relies on key radiation protection elements that tend to be mutually supportive and in combination provide reasonable assurance that the overall desired level of protection has been provided. For difficult situations, defense in depth can provide both a reasonable and appropriate approach to radiation protection.

Glucocorticoid-Induced Osteoporosis Program (GIOP): a novel, comprehensive, and highly successful care program with improved outcomes at 1 year.

INTRODUCTION: Patients who take chronic glucocorticoids (GC) are at increased risk of osteoporosis and fracture. Only a minority of patients who take chronic GC receive optimal osteoporosis prevention, diagnosis, and/or treatment. METHODS: An organized program of care--GIOP (Glucocorticoid-Induced Osteoporosis Program)--was designed and implemented. The program goals were to identify patients at risk of fracture, provide education, redesign and implement new pathways of care, and monitor outcomes. Two hundred chronic GC users were seen at baseline, and follow-up visits scheduled at 6 months and 1 year. RESULTS: Patient retention of knowledge, frequent exercise, and 25-OH Vitamin D levels all significantly improved at 1 year. A significant decrease in GC dose was seen. In terms of adherence, 91% of patients considered at high risk were taking a bisphosphonate or teriparatide at 1 year, and 96% of patients overall were adherent to their prescribed regimen of calcium, vitamin D, and prescription treatment (if indicated). Bone density at the spine and total hip increased significantly. CONCLUSIONS: GIOP is the first organized program of care for patients who take chronic GC that has demonstrated a clinically significant improvement in outcome. The program's design can be adapted and used by other health systems and organizations.

Vitamins and HIV therapy: a naturopathic perspective.

AIDS: During the early 1900s, scientists learned that "accessory nutrients" were needed in diets to maintain health; hence, during World War II the government developed the Recommended Daily Dietary Allowances (RDAs). Although intended to prevent nutritional deficiency diseases, the RDA is often used, incorrectly, as the optimum nutrient recommendation for a particular individual. RDAs do not take into account the effects of lifestyle (stress, smoking, etc.), nor do they consider nutritional needs associated with other disease processes (AIDS, cancer, etc.). The question of what the optimal dosages are for various vitamins and minerals boils down to the individual. Many nutrition studies research the specific effects of individual nutrients. However, nutrition study results often do not look at long term effects, nor at effects on other nutrients or other systems in the body. Nutritional studies should, therefore, be read with caution. Keep in mind that nutrient supplementation cannot take the place of a well-rounded diet.^ieng

The influence of exogenous PMS and HCG on the arachidonic acid content of the immature rat ovary.

The influence of exogenous PMS and/or HCG, on the arachidonic acid (C 20:4omega6) content of the immature rat ovary was examined. Changes in ovarian arachidonate content associated with hormone administration were assessed in total lipid extracts, and in several neutral and phospholipid fractions. Both relative percentage and absolute amounts of arachidonic acid in several lipids were measured as well as uptake of radioactivity into total lipid resulting from the administration of 3H-labeled arachidonic acid in vivo. On the basis of these studies, we conclude (1) PMS, with or without HCG promotes increased uptake of exogenous arachidonic acid into ovarian total lipids; (2) Arachidonic acid is a mojor fatty acid constituent from noncholine containing phosphatides at the onset of normal estrous (ca. 38 days) even in the animals which received no PMS or HCG; (3) Changes in ovarian arachidonic acid levels following gonadotropin administration are more striking in the two phospholipid fractions than in the two neutral lips examined; (4) PMS is associated with a rapid outpouring of ovarian lipid, accompanied by a high turnover of arachidonic acid which is enhanced or modified temporally by added HCG in vivo. These results provide the first quantitative evidence that gonadotropins may regulate prostaglandin biosynthesis in the ovary by their effects on the uptake, storage, or release of arachidonic acid, a major PG precursor, from specific ovarian lipids. While the data strongly suggest that the regulation of one or more ovarian esterases (cholesterol esterase, lipase, phospholipase) is the mechanism by which gonadotropins regulate PG biosynthesis, a direct action on PG synthetase is not ruled out.

Papillomavirus microbicidal activities of high-molecular-weight cellulose sulfate, dextran sulfate, and polystyrene sulfonate.

The high-molecular-weight sulfated or sulfonated polysaccharides or polymers cellulose sulfate, dextran sulfate, and polystyrene sulfonate were tested for microbicidal activity against bovine papillomavirus type 1 (BPV-1) and human papillomavirus type 11 (HPV-11) and type 40 (HPV-40). In vitro assays included the BPV-1-induced focus-forming assay and transient infection of human A431 cells with HPVs. The compounds were tested for microbicidal activity directly by preincubation with virus prior to addition to cell cultures and indirectly by addition of virus to compound-treated cells and to virus-coated cells to test inactivation of the virus after virus-cell binding. The data indicated that all three compounds showed direct microbicidal activity with 50% effective concentrations between 10 to 100 microg/ml. These concentrations were nontoxic to cell cultures for both assays. When a clone of C127 cells was tested for microbicidal activity, approximately 10-fold-less compound was required to achieve a 50% reduction in BPV-1-induced foci than for the uncloned parental C127 cells. Pretreatment of cells with compound prior to addition of virus also demonstrated strong microbicidal activity with dextran sulfate and polystyrene sulfonate, but cellulose sulfate required several orders of magnitude more compound for virus inactivation. Polystyrene sulfonate prevented subsequent infection of HPV-11 after virus-cell binding, and this inactivation was observed up to 4 h after addition of virus. These data indicate that the polysulfated and polysulfonated compounds may be useful nontoxic microbicidal compounds that are active against a variety of sexually transmitted disease agents including papillomaviruses.