Pharmacodynamic response to anti-thyroid drugs in Graves’ hyperthyroidism

The Section of Endocrinology and Investigative Medicine was funded by grants from the MRC, BBSRC, NIHR, an Integrative Mammalian Biology (IMB) Capacity Building Award, an FP7- HEALTH- 2009- 241592 EuroCHIP grant and was supported by the NIHR Biomedical Research Centre Funding Scheme. AA was supported by an NIHR Clinician Scientist award. SC was supported by an NIHR Clinical Lectureship. AC was supported by the NHS and BRC. WD was supported by an NIHR Research Professorship (RP-2014-05-001).Objective: Graves' disease is the commonest cause of hyperthyroidism in populations with sufficient dietary iodine intake. Anti-thyroid drugs (ATD) are often used as the initial treatment for Graves' hyperthyroidism, however there is a paucity of data relating the dose of ATD therapy to the effect on thyroid hormone levels, increasing the risk of both over- and under-treatment. We aimed to determine the pharmacodynamic response to the ATD carbimazole. Design: Retrospective cohort study. Methods: Participants were patients (n = 441) diagnosed with Graves' disease at Imperial College Healthcare NHS Trust between 2009 and 2018. The main outcome measure was change in thyroid hormone levels in response to ATD. Results: Baseline thyroid hormone levels were positively associated with TSH receptor antibody titres (P < 0.0001). Baseline free triiodothyronine (fT3) were linearly related to free thyroxine (fT4) levels in the hyperthyroid state (fT3 = fT4*0.97–11), and fell proportionately with carbimazole. The percentage falls in fT4 and fT3 per day were associated with carbimazole dose (P < 0.0001). The magnitude of fall in thyroid hormones after the same dose of carbimazole was lower during follow up than at the initiation visit. The fall in thyroid hormone levels approximated to a linear response if assessed at least 3 weeks after commencement of carbimazole. Following withdrawal of antithyroid drug treatment, the risk of relapse was greater in patients with higher initial fT4, initial TSH receptor antibody titre, males, smokers, and British Caucasian ethnicity. Conclusion: We identify a dose-response relationship for fall in thyroid hormones in response to carbimazole to aid in the selection of dose for Graves' hyperthyroidism.Publisher PDFPeer reviewe

Cerium oxide based particles as possible alternative to ZnO in sunscreens: Effect of the synthesis method on the photoprotection results

The aim of this study was to synthesize and characterize Ca-doped CeO2 nanopowder in order to determine in vitro the photoprotection efficiency of the combination – commercial TiO2/Ca-doped CeO2 – incorporated in emulsion. Cerium based particles were synthesized by two methods, co-precipitation and spray pyrolysis, in order to study the effect of the synthesis method on the photoprotection results. While both samples synthesized by co-precipitation and spray pyrolysis methods present the same crystalline structure and the same elementary composition, they differ in granulometry. The photoprotection results showed that the combinations tested are more efficient than the classical combination TiO2/ZnO in both UVB and UVA ranges. While the combination TiO2/CeO2 synthesized by co-precipitation allows an increase of the SPF of 27% compared to the classical combination, the combination TiO2/CeO2 synthesized by spray pyrolysis allows an increase of the PF-UVA of 19%

"Opinion on Skin Sensitisation Quantitative Risk Assessment for Fragrance Ingredients (QRA2) - Submission I" - SCCS/1589/17 - Final Opinion

International audienceThe SCCS adopted the final Opinion by written procedure on 30 July 2018 (90 pages) - https://ec.europa.eu/health/sites/health/files/scientific_committees/consumer_safety/docs/sccs_o_211.pd