Variations in radioiodine ablation: decision-making after total thyroidectomy.

BACKGROUND: The role of radioiodine treatment following total thyroidectomy for differentiated thyroid cancer is changing. The last major revision of the American Thyroid Association (ATA) Management Guidelines for Patients with Thyroid Nodules and Differentiated Thyroid Cancer in 2015 changed treatment recommendations dramatically in comparison with the European Association of Nuclear Medicine (EANM) 2008 guidelines. We hypothesised that there is marked variability between the different treatment regimens used today. METHODS: We analysed decision-making in all Swiss hospitals offering radioiodine treatment to map current practice within the community and identify consensus and discrepancies. RESULTS AND CONCLUSION: We demonstrated that for low-risk DTC patients after thyroidectomy, some institutions offered only follow-up, while RIT with significant activities is recommended in others. For intermediate- and high-risk patients, radioiodine treatment is generally recommended. Dosing and treatment preparation (recombinant human thyroid stimulation hormone (rhTSH) vs. thyroid hormone withdrawal (THW)) vary significantly among centres.

Second-derivative synchronous fluorescence spectroscopy for the simultaneous determination of fluphenazine hydrochloride and nortriptyline hydrochloride in pharmaceutical preparations.

A rapid, simple, and highly sensitive second-derivative synchronous fluorimetric (SDSF) method has been developed for the simultaneous analysis of binary mixtures of fluphenazine hydrochloride (FLZ) and nortriptyline hydrochloride (NTP) in their co-formulated tablets. The method is based upon measurement of the native fluorescence of these drugs at constant wavelength difference (Deltalambda) = 120 nm in acetic acid. The different experimental parameters affecting the fluorescence intensity of the studied drugs were carefully studied and optimized. The fluorescence-concentration plots were rectilinear over the range of 0.25-3.0 and 1-10 microg/ml for FLZ and NTP respectively, with lower detection limits (LOD) of 0.05 and 0.18 microg/ml and quantitation limits of 0.15 and 0.53 microg/ml for FLZ and NTP respectively. The proposed method was successfully applied for the determination of the studied compounds in their synthetic mixtures and in commercial co-formulated tablets. The results obtained were in good agreement with those obtained by the reference methods.

Spectrofluorimetric determination of famotidine in pharmaceutical preparations and biological fluids. Application to stability studies.

A simple, economic, selective, and stability indicating spectrofluorimetric method was developed for the determination of famotidine (FMT); is based on its reaction with 9, 10-phenanthraquinone in alkaline medium to give a highly fluorescent derivative measured at 560 nm after excitation at 283 nm. The fluorescence intensity-concentration plot was rectilinear over the concentration range of 50-600 ng/ml with minimum quantification limit (LOQ) of 13.0 ng/ml and minimum detection limit (LOD) of 4.3 ng/ml. The factors affecting the development of the fluorescence intensity of the reaction product were carefully studied and optimized. The method was applied for the determination of FMT in its dosage forms. The stability of the compound was studied, and the proposed method was found to be stability indicating one. The results obtained were in good agreement with those obtained by the official method. Furthermore, the method was applied for the determination of FMT in spiked and real human plasma. The mean % recovery (n = 4) was found to be 99.94 +/- 0.24, and 105.13 +/- 0.64 for spiked and real human plasma, respectively. The composition of the reaction product as well as its stability constant was also investigated. Moreover, the method was utilized to investigate the kinetics of both alkaline and oxidative induced degradation of the drug. The apparent first order rate constant and half life time of the degradation product was calculated. A proposal of the reaction pathway was postulated.