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It has been over half a century since propranolol, the first beta-blocker, was developed for medical treatment. Since that time a large number of compounds from this group have been synthesised and many are now in clinical use. The structure, function, pharmacokinetics, and mechanism of beta-blockers have been established. The possibilities for their use in treating different conditions continue to evolve. Since the discovery of later generation beta-blockers, such as carvedilol and nebivolol, the search for new compounds continues, and may include known substances with beta-blocking properties which could extend their therapeutic potential.

Background: Ampicillin (AMP) is frequently administered parenterally in critically ill patients with meningitis or endocarditis. Many of them require parallel infusion of total parenteral nutrition (TPN) admixtures. The aim of the study was to determine the physicochemical stability of AMP in TPN admixtures. Methods: AMP was added to two formulations of TPN admixtures differing in the lipid emulsion (Lipofundin® MCT/LCT 20% or LIPIDem®). Samples were stored at 4 ± 1 °C with light protection, and at 25 ± 1 °C with and without light protection to assess the impact of temperature and light on formulation stability. Every 24 h the pH, zeta potential, mean droplet diameter (MDD) of a lipid emulsion, and AMP concentration using HPLC method were determined. The assessment of stability and compatibility of TPN admixtures with vitamins and trace elements was carried out immediately after preparation and after 24 h of storage. Results: The addition of AMP as well as vitamins and trace elements to the TPN admixtures did not affect their physical stability. An increase in the pH value of approx. 0.6 and reduction of zeta potential were observed. The MDD of the lipid emulsions was below the limit of 500 nm (dynamic light scattering (DLS) method) and no fat droplets greater than 525 nm were observed (light diffraction (LD) method). The content of AMP after the first 24 h was within the acceptable limit of 90% for TPN admixtures stored at 4 ± 1 °C and 25 ± 1 °C with light protection. Conclusions: The results showed that co-administration of AMP in the same bag with TPN admixture at the tested dose is possible when used ex tempore and with light protection.

In the United States, the annual incidence of bladder cancer is approximately 70,000 new cases, with a mortality rate of approximately 15,000/year. The most common subtype (70%) of bladder cancer is superficial, namely hte non-muscle invasive disease form limited to the urothelium. The rate of progression and recurrence is up to 40 and 70%, respectively. Urothelial cell carcinoma of the bladder is typically treated with transurethral resection. The cancerous cells can float onto the adjacent epithelium, increasing the risk of recurrence. The standard of care is to offer adjuvant intravesical agents to reduce the risk of progression and recurrence. Current intravesical treatments are costly and are associated with special biohazard handling protocols. Patients are treated with intravesical therapy with bacillus Calmetter-Guerin (BCG) bacterium, or mitomycin C (MMC) following resection, both of which can cause moderate to severe side-effects which are rarely life-threatening. We previously examined the efficacy of epigallocatechin-3-gallate (EGCG)in comparison with MMC to prevent tumor cell implantation/growth in an animal model of superficial bladder cancer. Experiments revile that EGCG is slightly more effective than MMC at decreasing tumor cell implantation and consequent cancer growth in a bladder. This treatment requires the stringent sterile requirement of EGCG. EGCG can be unstable when sterilized at high temperatures. Thus, we evaluated two low temperature sterilization methods, such as ionizing radiation or the filtration method followed by freeze-drying. Both methods ensure the sterility of the sample; however, infrared and HPLC analysis revealed a slightly better stability of irradiated EGCG over the filtration method. The concentration of stable free radicals following irradiation was low, which are unlikely to exert any damaging effects to EGCG. Therefore, we consider that radiation will be the preferred method of EGCG sterilization, and that this may prove useful for the effective use of EGCG in the treatment of bladder cancer.

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