Retrovirus Drugs-Loaded PEGylated PAMAM for Prolonging Drug Release and Enhancing Efficiency in HIV Treatment

Polyamidoamine dendrimer (PAMAM) with its unique characteristics emerges as a potential drug delivery system which can prolong releasing time, reduce the side effects but still retaining treatment efficiency. In this study, methoxy polyethylene glycol modified PAMAM generation 3.0 (G3.0@mPEG) is prepared and characterized via 1H-NMR, FT-IR, and TEM. Subsequently, two antiretroviral agents (ARV) including lamivudine (3TC) and zidovudine (AZT) are individually encapsulated into G3.0@mPEG. The drug-loading efficiency, drug release profile, cytotoxicity and anti-HIV activity are then evaluated. The results illustrate that G3.0@mPEG particles are spherical with a size of 34.5 ± 0.2 nm and a drug loading content of about 9%. Both G3.0@mPEG and [email protected]@mPEG show no cytotoxicity on BJ cells, and G3.0@mPEG loading 3TC and AZT performs sustained drug release behavior which is best fitted with the Korsmeyer–Peppas model. Finally, the anti-HIV activity of ARV via Enzymatic Assay of Pepsin is retained after being loaded into the G3.0@mPEG, in which about 36% of pepsin activity was inhibited by AZT at the concentration of 0.226 mM. Overall, PAMAM G3.0@mPEG is a promising nanocarrier system for loading ARV in HIV treatment and prevention.

COST-MINIMIZATION ANALYSIS OF USING SHORT AND LONG-ACTING ERYTHROPOESIS-STIMULATING AGENTS FOR CORRECTION OF NEPHROGENIC ANEMIA AGAINST THE BACKGROUND OF SUBSTITUTION THERAPY

Clinical trials conducted in various countries indicate that the use of epoetin alfa in patients with nephrogenic anemia in chronic kidney disease can increase the effectiveness of treatment, reduce the incidence of cardiovascular and infectious complications, and reduce mortality in patients with chronic kidney disease.The aim of the article was to conduct a comparative clinical and economic assessment of the treatment costs of nephrogenic anemia in adult dialysis patients with recombinant human erythropoietins: epoetin alfa, darbepoetin and long-acting methoxy polyethylene glycol – epoetin beta.Materials and methods. The study took into account direct medical costs of nephrogenic anemia pharmacotherapy on the basis of 1 year maintenance therapy according to the following scheme: epoetin alfa – 3 times per week, darbepoetin alfa – once per week, methoxy polyethylene glycol – epoetin beta – once per 2 or 4 weeks. A “costs minimization” analysis was performed for equivalent maintenance epoetins doses for intravenous and subcutaneous administrations. Epoetin alpha equivalents were calculated for an average patient weighing 75 kg by converting a weekly dose of short-acting epoetin (7500 IU) into equivalent doses using dose conversion factors.Results. In the hypothetical cohort of patients under study, epoetin alfa, darbepoetin alfa, and methoxy polyethylene glycol – epoetin beta not differ in effectiveness in achieving target Hb values and in safety. With the equal effectiveness of the investigated drugs, in the studied patients, intravenous epoetin alfa can be less expensive drug therapy relative to the equivalent doses obtained by the calculation: darbepoetin by 14–24% and methoxy polyethylene glycol – epoetin beta by 4–30%. The change-over of patients to the subcutaneous administration makes it possible to decline a weekly dose of epoetin alfa by 20–30% by reducing the frequency of taking the drug to twice a week, and to reduce the cost of drug therapy by a third.Conclusion. Intravenous and subcutaneous administrations of epoetin alfa 2500 IU may be a more economical drug therapy in comparison with the equivalent doses of darbepoetin and methoxy polyethylene glycol – epoetin beta.

Ultrasound-Induced Microbubble Cavitation Combined with miR-34a-Loaded Nanoparticles for the Treatment of Castration-Resistant Prostate Cancer

Currently chemotherapy drugs are usually used as first-line treatments for castration-resistant prostate cancer (CRPC), but they are ineffective and accompanied by serious side effects. MicroRNA-34a (miR-34a) simultaneously targets multiple genes related to the cell apoptosis in CRPC cells without obvious side effects. It has shown great potential in the treatment of CRPC. Previous studies focused on miR-34a increasing the sensitivity of chemotherapy drugs to chemoresistant prostate cancer cells. There are few researches on miR-34a alone in the treatment of CRPC. But the macromolecular miR-34a is difficult to enter the cell and is easily degraded by nuclease. Therefore, we constructed methoxy polyethylene glycol-polylacticco-glycolic acid-polylysine (mPEG-PLGA-PLL) nanoparticles to encapsulate miR-34a (miR-34a/NP). The results showed that miR-34a/NP protects miR-34a from degradation by nucleases and can be phagocytized by PC-3 CRPC cells. Ultrasound induces microbubble cavitation (UIMC) improves cell membrane permeability and capillary gaps, and further promotes miR-34a/NP to enter cells PC-3 and prostate cancer xenografts. The miR-34a/NP that enters the cell and tumor tissue releases miR-34a, which suppressed CRPC cells PC-3 proliferation, promoted its apoptosis, and inhibited the growth of CRPC xenografts. Our research verified that miR-34a/NP, especially combined with UIMC, has a significant anti-tumor effect on CRPC.

Amphiphilic Polymer-Modified Uniform CuFeSe2 Nanoparticles for CT/MR Dual-Modal Imaging

Recently, magnetic photothermal nanomaterials have attracted much attention in the diagnosis and treatment of cancer. In this study, we developed the ultrasmall magnetic CuFeSe2 nanoparticles for CT/MR dual-modal imaging. By controlling the reaction time and condition, CuFeSe2 nanoparticles were synthesized by a simple directly aqueous method. After modification with copolymer methoxy polyethylene glycol-polycaprolactone (MPEG-PCL), the obtained MPEG-PCL@CuFeSe2 nanoparticles showed excellent water solubility, colloidal stability, and biocompatibility. In addition, they also exhibited superparamagnetism and X-ray’s characteristics. For these properties, they will become ideal nanomaterials for CT/MR dual-modal imaging.