Investigation of pollution levels originated from anthropogenic gadolinium in Ankara Stream
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
Authors: Alkan, Ali; Alkan, Nigar; Yanar, Bahtiyar
Abstract
Research on pollution caused by gadolinium (Gd) based on compounds as a result of its use in high technological applications, especially in the health sector, has recently become very interesting. This study aims to investigate the determination of the environmental pollution levels of anthropogenic Gd and its possibility of use as an anthropogenic pollutant indicator in the Ankara Stream (Turkey) selected as the pilot stream. Within the scope of the research, Gd levels were determined in water and sediment samples taken in spring and autumn periods in a total of seven different stations, three of which in Ankara Stream and one for each in its tributaries (cubuk Stream, Hatip Stream, Incesu Creek, Ova Stream). Some parameters related to water and sediment quality were also measured at the stations. Temperature, pH, electrical conductivity, and dissolved oxygen were measured in situ. Gd concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS) technique using samples filtered from 0.45-mu m filters at the time of sampling in water samples. The grain sizes of sediment samples were carried out by conventional wet sieve analysis. Gd levels were determined by ICP-MS after digestion of sediment samples passing through 63-mu m particle grain size. Also, total organic carbon (TOC) and total phosphorus (TP) levels were measured by classical methods in sediment samples. Although the Gd concentrations measured in the water samples taken from the stations in the Ankara Stream were found to be quite high compared with the tributaries of Ankara Stream. The highest mean Gd concentration (0.347 +/- 0.057 mu g/L) measured in this study was higher than that of at the most rivers in the world. There was no statistically significant difference between the stations in terms of Gd concentrations in the sediment samples. As a result of this study, it was revealed that Gd can be used as an indicator parameter in the monitoring of anthropogenic pollution of aquatic environment where potential Gd pollution sources.
Pegfilgrastim (PEG-G-CSF) induces anti-PEG IgM in a dose dependent manner and causes the accelerated blood clearance (ABC) phenomenon upon repeated administration in mice
EUROPEAN JOURNAL OF PHARMACEUTICS AND BIOPHARMACEUTICS
Authors: Elsadek, Nehal E.; Abu Lila, Amr S.; Emam, Sherif E.; Shimizu, Taro; Takata, Haruka; Ando, Hidenori; Ishima, Yu; Ishida, Tatsuhiro
Abstract
Pegfilgrastim is a recombinant PEGylated human granulocyte colony-stimulating factor (G-CSF) analog filgrastim (trade names Neulasta (R) or G-Lasta (R)) that stimulates the production of white blood cells (neutrophils). It is employed as an alternative to filgrastim (G-CSF) for chemotherapy-induced neutropenia in patients due to its longer half-life. In clinical settings, PEG-G-CSF is administered to cancer patients via both the s.c. and i.v. routes. In a murine study, we showed that, regardless of administration route, initial doses of PEG-G-CSF above 0.06 mg/kg elicited anti-PEG immune response in a dose-dependent manner. I.v. administration elicited higher levels of anti-PEG IgM than the s.c. route. Initial doses of PEG-G-CSF (6 mg/kg) that were high enough to trigger production of anti-PEG IgM, did not trigger the accelerated clearance of a lower subsequent dose (0.06 mg/kg) that was similar to i.v. clinical doses of PEG-G-CSF, but when the subsequent dose of PEG-G-CSF was raised to (6 mg/kg), the initial dose triggered the accelerated clearance of the second dose via an anti-PEG IgM-mediated complement activation. Similar observations were noted when an increased PEG-OVA dose was given as the second dose, indicating that pre-existing and/or treatment-induced anti-PEG antibodies might compromise the therapeutic activity and/or reduce tolerance of other PEGylated formulations. To the best of our knowledge, this is the first report to suggest the induction of the ABC phenomenon upon repeated injections of pegfilgrastim. In the clinic, cancer patients, receiving multiple cycles of chemotherapy, receive multiple cycles of pegfilgrastim to avoid infections and substantial morbidity. The ABC phenomenon to pegfilgrastim appears to be the cause of loss of clinical benefit of sequential treatments with pegfilgrastim in patients.