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Toxicity study of silver nanoparticles synthesized using seaweed Sargassum angustifolium in common carp, Cyprinus carpio
2016
Bita, Seraj | Mesbah, Mehrzad | Shahryari, Ali | Ghorbaanpoor Najafabadi, Masoud
BACKGROUND: Application of green chemistry to the synthesis of nanomaterials is of vital importance in medicinal and technological aspects. Recently, synthesis of silver nanoparticles using plants and marine macro algae to adapt this approach to the environment, has become more popular. Objectives: The purpose of this study is biological synthesis of silver nanoparticles using seaweed, Sargassum angustifolium, and determining its toxicity in common carp. Methods: First, synthesis of silver nanoparticles using Sargassum algae was conducted and then acute toxicity of these silver nanoparticles was investigated at static renewal condition during 96 hours in common carp according to standard methods (1998) OECD. Results: TEM analysis showed that the average size of the bionanoparticles was found to be 32.54 nm and spherical in shape. The toxicity results showed that the LC50 at 24, 48, 72 and 96-h after exposure was 79.54 ± 0.007, 52.17 ± 0.006, 30.62 ± 0.008 and 11.34 ± 0.016 mg/l respectively. Conclusions: Analysis related to the characterization of the properties of silver nanoparticles proves bioreduction of silver ions by sargassum seaweed extract. According to the results the mortality rates of common carp showed an increasing trend with increasing concentration and exposure time, which indicates the toxicity of this substance in high concentration for common carp.
Показать больше [+] Меньше [-]Elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate beads in vitro
2016
OBJECTIVE To characterize the elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CSH) beads in vitro. SAMPLE 60 carboplatin-impregnated CSH beads and 9 CSH beads without added carboplatin (controls). PROCEDURES Carboplatin-impregnated CSH beads (each containing 4.6 mg of carboplatin [2.4 mg of platinum]) were placed into separate 10-mL plastic tubes containing 5 mL of PBSS in groups of 1, 3, 6, or 10; 3 control beads were placed into a single tube of PBSS at the same volume. Experiments were conducted in triplicate at 37°C and a pH of 7.4 with constant agitation. Eluent samples were collected at 1, 2, 3, 6, 12, 24, and 72 hours. Samples were analyzed for platinum content by inductively coupled plasma–mass spectrometry. RESULTS The mean concentration of platinum released per carboplatin-impregnated bead over 72 hours was 445.3 mg/L. Cumulative concentrations of platinum eluted increased as the number of beads per tube increased. There was a significant difference in platinum concentrations over time, with values increasing over the first 12 hours and then declining for all tubes. There was also a significant difference in percentage of total incorporated platinum released into tubes with different numbers of beads: the percentage of eluted platinum was higher in tubes containing 1 or 3 beads than in those containing 6 or 10 beads. CONCLUSIONS AND CLINICAL RELEVANCE Carboplatin-impregnated CSH beads eluted platinum over 72 hours. Further studies are needed to determine whether implantation of carboplatin-impregnated CSH beads results in detectable levels of platinum systemically and whether the platinum concentrations eluted locally are toxic to tumor cells.
Показать больше [+] Меньше [-]Pharmacokinetics of orally administered low-dose rapamycin in healthy dogs
2016
Larson, Jeanne C. | Allstadt, Sara D. | Fan, Timothy M. | Khana, C. (Chand) | Lunghofer, Paul J. | Hansen, Ryan J. | Gustafson, Daniel L. | Legendre, Alfred M. | Galyon, Gina D. | LeBlanc, Amy K. | Martin-Jimenez, Tomas
OBJECTIVE To determine the pharmacokinetics of orally administered rapamycin in healthy dogs. ANIMALS 5 healthy purpose-bred hounds. PROCEDURES The study consisted of 2 experiments. In experiment 1, each dog received rapamycin (0.1 mg/kg, PO) once; blood samples were obtained immediately before and at 0.5, 1, 2, 4, 6, 12, 24, 48, and 72 hours after administration. In experiment 2, each dog received rapamycin (0.1 mg/kg, PO) once daily for 5 days; blood samples were obtained immediately before and at 3, 6, 24, 27, 30, 48, 51, 54, 72, 75, 78, 96, 96.5, 97, 98, 100, 102, 108, 120, 144, and 168 hours after the first dose. Blood rapamycin concentration was determined by a validated liquid chromatography–tandem mass spectrometry assay. Pharmacokinetic parameters were determined by compartmental and noncompartmental analyses. RESULTS Mean ± SD blood rapamycin terminal half-life, area under the concentration-time curve from 0 to 48 hours after dosing, and maximum concentration were 38.7 ± 12.7 h, 140 ± 23.9 ng•h/mL, and 8.39 ± 1.73 ng/mL, respectively, for experiment 1, and 99.5 ± 89.5 h, 126 ± 27.1 ng•h/mL, and 5.49 ± 1.99 ng/mL, respectively, for experiment 2. Pharmacokinetic parameters for rapamycin after administration of 5 daily doses differed significantly from those after administration of 1 dose. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that oral administration of low-dose (0.1 mg/kg) rapamycin to healthy dogs achieved blood concentrations measured in nanograms per milliliter. The optimal dose and administration frequency of rapamcyin required to achieve therapeutic effects in tumor-bearing dogs, as well as toxicity after chronic dosing, need to be determined.
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