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The purposes of this study were as follows: (1) to radiolabel ibandronic acid (IBA, a third-generation bisphosphonate) with 177 Lu, investigating optimal labeling conditions, and (2) to analyze biodistribution and imaging properties of intravenous 177 Lu-ibandronate (177 Lu-IBA) administered in animals. 177 Lu-labeled methylene diphosphonate (177 Lu-MDP) served as a comparator agent. Differing proportions of IBA solution and 177 LuCl3 solution were combined to determine an optimal ratio for radiolabeling purposes, varying pH, temperature, and time to establish ideal reactivity conditions. Radiochemical purity of the labeled compounds was then assessed by paper chromatography. In vitro and in vivo stabilities were also measured at specific time intervals. In Kunming mice, biodistributions of 177 Lu-IBA and 177 Lu-MDP and respective agent activities in various organs were monitored by gamma counter, and we performed single photon computed tomography/computed tomography (SPECT/CT) imaging of 177 Lu-IBA in normal New Zealand White rabbits. Radiolabeling yields for 177 Lu-IBA proved to be >97% within 30 minutes at 90°C, and its radiochemical purity ensured stability in vitro and in vivo. Furthermore, we found that 177 Lu-IBA is readily soluble in water, showing higher skeletal uptake than 177 Lu-MDP but lower uptake by liver and spleen. The image quality of 177 Lu-IBA was so clear that even after 6 days, analysis was still feasible.

In this work, the dissolution behaviors of a series of sodium alkylbenzenesulfonates (NaLAS) tablets with different moisture contents and neutralization degrees were investigated in aqueous solution. The ANOVA-based, model-independent and model-dependent methods were employed to perform comparison analyses on dissolution profiles. The measurements of powder X-ray diffraction patterns and mechanical properties elucidate distinct differences in each formula. The results show that ANOVA provides a possibility for finding the source of differences among different variables, and the model-independent methods including the k values and mean dissolution time are easy to interpret and perform comparison analyses. The Hixson–Crowell model gives satisfactory correlation results for the dissolution data and the dissolution kinetics parameters are obtained. The inhibition effects of neutralization degree and moisture content on NaLAS dissolution were examined, which reveals that the increase in lamellar phase proportion leads to the reduction of dissolution rate. The comparison analyses performed in this work form part of a methodology for dissolution profile prediction and comparison.

Increasingly recognized importance has been assumed for microRNA (miRNA) in the regulation of the delicate balance of gene expression. In our study, we aimed to explore the regulation role of miR181c towards Six2 in metanephric mesenchyme (MM) cells. Bioinformatics analysis, luciferase assay and semi-quantitative real-time (RT) PCR, subsequently RT PCR, Western blotting, 5-ethynyl-2'-deoxyuridine cell proliferation assay, Cell Counting Kit-8 assay, immunofluorescence and flow cytometry, were employed to verify the modulation function of miR181c on Six2 in the mK3 MM cell line that is one kind of MM cells. miR181c was predicted to bind the 3' untranslated region of Six2 by bioinformatics analysis, which was subsequently validated by the in vitro luciferase reporter assay. Moreover, transfection of miR181c mimic can decrease the expression of Six2 both in mRNA and protein levels in mK3 cells. Still, ectopic expression of miR181c inhibits the proliferation, promotes the apoptosis and even makes the nephron progenitor phenotype lose mK3 cells. These results revealed the ability of a single miRNA-miR181c to downregulate the expression of Six2, restrain the proliferation and promote the apoptosis that even makes the nephron progenitor phenotype lose MM cells, suggesting a potential role of miR181c during the kidney development.

Solubility and metastable zone width (MSZW) of DL-tartaric acid (DL-TA) in aqueous solution have been determined. Solubility of DL-TA was measured in the temperature range from 0 to 50 °C at atmospheric pressure by means of the conventional polythermal method using Turbidity Monitoring Technique, which was verified by a gravimetric method. The dissolution enthalpy and entropy of DL-TA were then calculated from the solubility data using van't Hoff equation. Two approaches was used to estimate the nucleation kinetics from the measured metastable zone width data, the self-consistent approach and the approach based on 3D nucleation. In addition, the metastable zone width slightly decreases with increasing agitation rate and was independent of working volume.