75 research outputs found
Effect of obesity, age and gender on glomerular filtration rate measured in normal adults
International audienc
Comparison of fifteen immunoassays for the measurement of serum MUC-1/CA 15-3 in breast cancer patients
Peer Reviewe
Dealing with dry waste disposal issues associated with 177mLu impurities: a long-term challenge for nuclear medicine departments
Abstract Purpose A strategy for management of radioactive waste associated with 177Lu-dotatate (Lutathera®) treatments was established in our institution, based on predicted storage times of 3–5 years extrapolated from the results of a 2-year measurement study. The aim of this work was to validate this strategy by identifying contaminants and confirming disposal based on the clearance level twice-the-background was within expected time frames. Methods We conducted a prospective series of measurements of radioactive waste associated with the first 65 treatments administered. Sequential measurements of the first 45 vials used were performed on a dose calibrator to identify contaminants. Exposure rates in contact were monitored with a dose ratemeter on a 6-monthly basis for all waste stored: 46 empty vials, 19 vials partially used and 61 biohazard containers. Results Initial median activity of the first vials used was 118 MBq [4–4188 MBq]. For each vial, the decay curve of activity obtained was adjusted to a bi-exponential model. The major component, representing 99.7% of the activity, has a median half-life of 6.6 days [5.7–7.2 days] corresponding to 177Lu. The second, representing only 0.3% of the activity and having a median half-life of 152 days [104–205 days] corresponding to 177mLu, determines necessary storage times. Partially used vials can be disposed of after 5 years, other waste after 3 years. Compliance with the regulatory clearance level is achieved within expected time frames. Conclusion Although only present as traces, 177mLu associated with the direct production route results in major radioactive waste disposal issues for hospitals. Availability of radiopharmaceuticals without impurities appears to be crucial for an expanding use of targeted radionuclide therapy
Improved synthesis and in vitro evaluation of the cytotoxic profile of oxysterols oxidized at C4 (4 alpha- and 4 beta-hydroxycholesterol) and C7 (7-ketocholesterol, 7 alpha- and 7 beta-hydroxycholesterol) on cells of the central nervous system
International audienceWhereas the biological activities of oxysterols oxidized at C7 (7-ketocholesterol (71(C), 76-hydroxycholesterol (7 6-0HC), 7 alpha-hydroxycholesterol (7 alpha-OHC)) are well documented, those of oxysterols oxidized at C4 (4 beta-hydroxycholesterol (4 beta-OHC), 4 alpha-hydroxycholesterol (4 alpha-OHC)) are not well known, especially on the cells of the central nervous system. Therefore, an improved methodology has been validated for 4 beta-OHC and 4 alpha-OHC synthesis, and the effects on cell viability and cell growth of these molecules were studied on immortalized, tumoral and normal brain cells (158N, C6 and SK-N-BE cells, and mixed primary cultures of astrocytes and oligodendrocytes). Whereas inhibition of cell growth with 7KC, 7 6-OHC, and 7 alpha-OHC is associated with a decrease of cell viability (cytotoxic activities), our data establish that 4 beta-OHC and 4a-OHC have no effect on cell viability, and no or minor effect on cell growth evocating cytostatic properties. Thus, comparatively to oxysterols oxidized at C7, the toxicity of oxysterols oxidized at C4 is in the following range of order: 7KC > 76-OHC > 7 alpha-OHC > (4 alpha-OHC > 4 alpha-OHC). Interestingly, to date, 4 beta-0HC and 4a-OHC are the only oxysterols identified with cytostatic properties suggesting that these molecules, whereas not cytotoxic, may have some interests to counteract cell proliferation
Electrical and Morphological Investigations of Electrical Contacts used in Low-Voltage Circuit-Breakers
Oral presentation on line in 2021 (due to Covid pandemic)International audienc
Changes in 18F-FDG tumor metabolism after a first course of neoadjuvant chemotherapy in breast cancer: influence of tumor subtypes
International audienc
Absence of oxysterol-like side effects in human monocytic cells treated with phytosterols and oxyphytosterols
Oxysterols, found in some commonly consumed foods, can induce a wide range of cytotoxic effects, which have been extensively studied. On the other hand, the side effects of phytosterols and oxyphytosterols are less well-known. Over the past few years, different types of foods have been enriched with phytosterols on the basis of the properties of these compounds that reduce circulating cholesterol levels in certain experimental conditions. It is therefore important to gain better knowledge of the risks and benefits of this type of diet. In this study, conducted in human monocytic U937 cells, the ability of phytosterols (sitosterol, campesterol) and oxyphytosterols (7 beta-hydroxysitosterol, 7-ketositosterol) to induce cell death, polar lipid accumulation, and pro-inflammatory cytokine (MCP-1; IL-8) secretion was determined and compared to that of oxysterols (7-ketocholesterol, 7 beta-hydroxycholesterol). Phytosterols and oxyphytosterols had no significant effects on the parameters studied; only 7 beta-hydroxysitosterol slightly increased cell death, whereas at the concentration used (20 mu g/mL), strong cytotoxic effects were observed with the oxysterols. With sitosterol, campesterol, and 7-ketositosterol, IL-8 secretion was decreased, and with campesterol the intracellular polar lipid level was reduced. The data show that phytosterols and oxyphytosterols have no oxysterol-like side effects, and they rather argue in favor of phytosterols' beneficial effects
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