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Objectives: We aimed to comprehensively evaluate poly-lactide polymer degradation and sirolimus release kinetics from a drug-eluting stent matrix in the in vivo setting using a nuclear magnetic resonance (NMR) method. Methods: In 22 domestic swine, 18 biodegradable polymer-only coated stents (BPSs) and 36 biodegradable polymer-coated sirolimus-eluting stents (BP-SES) were implanted in coronary arteries with 115% overstretch. The animals were sacrificed at 1, 3, 7, 14, 28, and 56 days following baseline procedures. Vessel segments with BPS were harvested to evaluate polymer degradation with a NMR method, whereas BP-SES to analyze sirolimus tissue uptake and retention. Additionally, 8 BP-SES were implanted for histological analysis for 90 days of follow-up. Results: The NMR showed a gradual absorption of the polymer over the 6 consecutive time points, from 5.48 µg of the polymer on the stent at 1-day follow-up, through 4.33 µg at 3 days, 3.16 µg at 7 days, 2.42 µg at 14 days, 1.92 µg at 28 days to 1.24 µg in the last day of the study. The curve of polymer degradation corresponds well with the pharmacokinetic profile of sirolimus eluted from its surface and measured at identical time points. In histopathology, at 90 days, complete healing and biocompatibility were reported. Conclusions: The utilization of NMR method for BP absorption kinetics evaluation is a useful tool, which may be widely adopted to test other biodegradable implants. Further, it may substantially improve their safety and efficacy by facilitating programmed polymer and drugs elution.

A novel polyazomethines bearing triphenylamine core and a proper model compound were synthesized and their spectroscopic (FTIR, 1 H NMR) and optical (UV-vis, photoluminescence) properties and also a molecular dynamic calculations were investigated. The polymers which were soluble in organic solvents (chloroform, dimethylacetamide, m-cresol) and formed transparent foils, emitted blue light and their photoluminescence band and intensity were solvent dependent. Additionally, the effects of blending the new polyazomethines with other polymers—PMMA, polyvinylophenol on UV-vis spectra were examined. Non-covalent ionic-type interactions between azomethines and methanesulfonic acid (MSA), m-cresol (MC) and p-chlorophenol (pClp) were also investigated. The structure formation of azomethines complexes are discussed on the basis of 1H NMR and FTIR. Photoluminescence and absorption properties of the azomethines compounds after doping with MSA, MC and pClp were tested.

New luminescent materials - aromatic polyketanils (PKs) containing p-phenylene and biphenylene linkages in the backbone and electron-donating side-group substitutions have been synthesized via melt polycondensation (180°C, 24 h). Their structures were confirmed by elemental and spectral Fourier transform infrared, 13Cand 1H NMR, and ultraviolet-visible (UV-vis) analysis. All the PKs were solution-processable and thermally stable, making them potential candidate materials for applications in microelectronics and aerospace. These ketanil polymers showed high thermal stability and well-defined glass transition temperatures ( Tg). The temperature at which the polymers lose 10% of their weight ( T10) ranged from 420 to 520°C. Depending on the polymer structure, PKs showed Tg values in the range of 133 to 244°C. Moreover, the polymers emit either blue radiation or green radiation depending on the mutual presence of conjugated and saturated chain segments. The HOMO/LUMO energy gap of the polymers was in the range of 2.74-2.19 eV. The photoluminescence properties of the PKs after protonation with DL-camphor-10-sulfonic acid (CSA) were tested. The structure formation of (PKs)1(CSA)2 complexes are discussed on the basis of 1HNMRspectroscopy.

The study population included healthy men and hypertensive employees of zinc and lead steelworks in the south of Poland. Workers exposed to lead (n=137) were divided into two groups: the first included employees with low exposure to lead (LL) with mean blood lead (PbB) 25-40 μg/dL and the second one with PbB over 40 μg/dL (HL group). The administration workers (n=35) were the control group. Evaluation of lipids and oxidative changes of cholesterol and lipids were estimated in blood samples. No significant changes in concentration of 7-ketocholesterol and blood lipids (cholesterol, HDL, LDL, triglycerides) were found. Lipid peroxidation (LP) was significantly higher in both exposed groups in plasma and in the HL group in erythrocytes when compared with control. There can be two independent sources of LP increase: the first is connected with the direct effect of lead’s ions on erythrocytes, the second is the prooxidative effect of delta-aminolevulinic acid. Hypertension in the HL group when compared with people with PbB below 40 μg/dL (OR 4.4, 95%CI 1.4-40 mg/dL was found more often. LP significantly increased by about 71% and concentration of 7-ketocholesterol by about 122% in hypertensives when compared with normotensives in the HL group.

A study of the release of β-estradiol from d,l-lactide/ε-caprolactone copolymers was performed. The copolymers were used in the form of films (in vitro) and microspheres (in vivo). The dl-lactide content was varied from 50 to 94% in the copolymers studied. It was found that an almost constant rate of β-estradiol release for about 70 days can be achieved by the application of appropriately selected material.