Superparamagnetic iron oxide nanoparticles (SPION) are extensively used for magnetic resonance imaging (MRI) and magnetic particle imaging (MPI), as well as for magnetic fluid hyperthermia (MFH). We here describe a sequential centrifugation protocol to obtain SPION with well-defined sizes from a polydisperse SPION starting formulation, synthesized using the routinely employed co-precipitation technique. Transmission electron microscopy, dynamic light scattering and nanoparticle tracking analyses show that the SPION fractions obtained upon size-isolation are well-defined and almost monodisperse. MRI, MPI and MFH analyses demonstrate improved imaging and hyperthermia performance for size-isolated SPION as compared to the polydisperse starting mixture, as well as to commercial and clinically used iron oxide nanoparticle formulations, such as Resovist ® and Sinerem ®. The size-isolation protocol presented here may help to identify SPION with optimal properties for diagnostic, therapeutic and theranostic applications.

Background: Teriflunomide is a once-daily oral immunomodulatory agent approved for the treatment of relapsing–remitting multiple sclerosis (MS). We aimed to obtain data on the effectiveness, tolerability, and subject satisfaction with teriflunomide (Aubagio®) under clinical practice conditions in unselected MS patients. Methods: This work was a non-interventional, prospective, longitudinal, observational study in 307 sites in Germany. Results: A total of 1128 patients were eligible for the efficacy analysis [67.5% female; mean age (± standard deviation) 44.9 ± 9.7 years, range 20–73 years]. Time since first MS symptoms was 10.6 ± 8.2 years, and time since MS diagnosis was 8.9 ± 7.6 years. Expanded Disability Status Scale (EDSS) score at inclusion was 2.3 ± 1.5 (70.4% with score < 3.5). The mean observation period was 16.3 ± 9.1 months. A total of 75.2% had received previous disease-modifying therapies (DMTs) at any time. Of these patients, 504 (44.7%) received no DMT within 6 months of study entry, 593 patients (52.6%) had DMT discontinued prior to study entry [glatiramer acetate in 10.6%, subcutaneous interferon-beta 1a (IFNβ-1a) in 9.3%, intramuscular IFNβ-1a or IFNβ-1b in 6.6% each, azathioprine oral in 0.4%, other in 7.3%, last medication not known in 12.0%]. The mean annualized relapse rate decreased from 0.87 in the 24 months prior to study entry to 0.35 in the 24 months after study entry ( n = 468; p ⩽ 0.001). EDSS and Fatigue Severity Scale remained stable. In patients who received previous MS treatments, Treatment Satisfaction Questionnaire (TSQM-9) values (maximum = 100), for the observation at 24 months improved by 8.1 points for effectiveness, 17.0 points for convenience, and 15.3 points for global satisfaction ( p ⩽ 0.001 each, compared with study entry). In the safety cohort ( n = 1139), the proportion of patients with adverse events (AEs) of any severity was 35.8%, and with serious events 13.0%. The most frequently reported AEs were diarrhea ( n = 55), followed by MS relapse ( n = 48), hair thinning ( n = 38), and viral upper respiratory tract infection ( n = 31). Conclusions: Relapse rate was halved during the observation period in comparison with the same time period before study entry. Patient satisfaction with teriflunomide was high in this real-world observation of patients, the majority of whom switched from other DMTs. The safety and tolerability profile of teriflunomide was similar to that reported in previous clinical trials.

Advanced renal cell carcinoma (RCC) has a poor prognosis and is characterized by an unpredictable clinical course. The aim of this study was to assess the systemic phospholipid distribution as a possible marker of tumor stage and tumor spread beyond the kidney. To this end, the effect of renal cell carcinoma (RCC) on phospholipid concentrations in blood plasma using 31P NMR spectroscopy was studied in: (a) 29 patients with RCC prior to nephrectomy; (b) 19 healthy volunteers; (c) three patients with other renal tumors (renal metastases of bronchial carcinoma and of renal pelvic carcinoma, and a benign renal tumor). Furthermore, the phospholipid concentrations of eight patients of group (a) were determined 6 months after nephrectomy, when they were in remission. We found considerable deviations in the concentrations of the lysophosphatidylcholines (LPC1, LPC2) in both male and female patients with RCC compared to healthy volunteers (male--LPC1 0.217+/-0.062 vs 0.297+/-0.049 mmol/l, LPC2 0.036+/-0.014 vs 0.068+/-0.024 mmol/l; female--LPC1 0.195+/-0.071 vs 0.296+/-0.044 mmol/l, LPC2 0.037+/-0.027 vs 0.044+/-0.014 mmol/l). In addition, female patients with RCC showed lower concentrations of phosphatidylcholines (PC; 1.409+/-0.268 vs 1.947+/-0.259 mmol/l). The low phospholipid concentrations normalized for patients in remission. Phospholipid concentrations were found to depend on tumor stage and metastatic spread. The deviations in phospholipid concentrations (LPC1, LPC2, PC) observed may be attributable to systemic effects caused by the tumor as well as changes in enzyme activities.

Many efforts are made worldwide to establish magnetic fluid hyperthermia (MFH) as a treatment for organ-confined tumors. However, translation to clinical application hardly succeeds as it still lacks of understanding the mechanisms determining MFH cytotoxic effects. Here, we investigate the intracellular MFH efficacy with respect to different parameters and assess the intracellular cytotoxic effects in detail. For this, MiaPaCa-2 human pancreatic tumor cells and L929 murine fibroblasts were loaded with iron-oxide magnetic nanoparticles (MNP) and exposed to MFH for either 30 min or 90 min. The resulting cytotoxic effects were assessed via clonogenic assay. Our results demonstrate that cell damage depends not only on the obvious parameters bulk temperature and duration of treatment, but most importantly on cell type and thermal energy deposited per cell during MFH treatment. Tumor cell death of 95% was achieved by depositing an intracellular total thermal energy with about 50% margin to damage of healthy cells. This is attributed to combined intracellular nanoheating and extracellular bulk heating. Tumor cell damage of up to 86% was observed for MFH treatment without perceptible bulk temperature rise. Effective heating decreased by up to 65% after MNP were internalized inside cells.