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Takuji Mizuno - One of the best experts on this subject based on the ideXlab platform.

  • Biological half life of radioactive cesium in japanese rockfish sebastes cheni contaminated by the fukushima daiichi nuclear power plant accident
    Journal of Environmental Radioactivity, 2015
    Co-Authors: Akira Matsumoto, Yu Shigeoka, Hisayuki Arakawa, Naoto Hirakawa, Yoshiaki Morioka, Takuji Mizuno
    Abstract:

    Since the Fukushima accident in March 2011 the concentration of radioactive cesium in Japanese rockfish (Sebastes cheni) has been decreasing slower than other fish species. The aim of this study was therefore to investigate the possibility of slow elimination rate (i.e., relatively longer Tb) as one of the reasons for the slow decrease in 137Cs concentrations in Japanese rockfish (S. cheni). To do this, we reared twenty-three individuals of this species for a period of about 1 year, during which time we measured the 137Cs concentrations and γ-ray spectra 14 times by using a high-efficiency NaI(Tl) scintillator. We then examined the relationship between the 137Cs concentrations and the total length of each individual. We estimated the Biological Half-Life (Tb, day) for each individual using the total number of 137Cs counts in the energy region, and examined the effects of total length and 137Cs concentration on Tb by generalized linear model (GLM). We also examined the effect of sex, total length, seawater temperature, and the 137Cs concentration of seawater on temporal changes in the 137Cs count reduction rate by GLM. There was no clear relationship between the corrected whole-body 137Cs concentrations and the total length in females, however there was a significant positive correlation between these two variables in males. The difference between males and females may be attributable to variation in the degree of dilution because of variable growth of individuals, and suggests that the 137Cs concentrations of small individuals may be greatly diluted because of faster growth. However, there was no significant difference in Tb between sexes. The mean Tb (±SD) in all individuals was 269 (±39) days; this Tb value is 2.7–5.4 times longer than past Tb values (marine fish: 50–100 days), and is thought to be one of the reasons for the slower decrease in 137Cs concentrations in this species than other fish species on the coast of Fukushima. The GLM showed significant effects of both total length and 137Cs concentration on Tb, which may reflect a reduction in the metabolic rate with increased body size (i.e., aging) and gradient of concentration against seawater. The GLM also showed a significant positive effect of seawater temperature on the reduction rate of the 137Cs counts (D, day−1). Therefore, D was clearly related to seasonal variations in the temperature of seawater, and this relationship may be attributable to changes in the metabolic rate that are controlled by variations in the seawater temperature. From these measurements, we examined the processes that control reductions in 137Cs radioactivity.

Michael J. Anderson - One of the best experts on this subject based on the ideXlab platform.

Hélène Fenet - One of the best experts on this subject based on the ideXlab platform.

  • Bioconcentration of two pharmaceuticals (benzodiazepines) and two personal care products (UV filters) in marine mussels (Mytilus galloprovincialis) under controlled laboratory conditions
    Environmental Science and Pollution Research, 2012
    Co-Authors: Elena Gomez, Morgane Bachelot, Clotilde Boillot, Dominique Munaron, Serge Chiron, Claude Casellas, Hélène Fenet
    Abstract:

    Bioaccumulation is essential for gaining insight into the impact of exposure to organic micropollutants in aquatic fauna. Data are currently available on the bioaccumulation of persistent organic pollutants, but there is very little documentation on the bioaccumulation of pharmaceuticals and personal care products (PPCPs). The bioconcentration of selected PPCPs was studied in marine mussels (Mytilus galloprovincialis). The selected PPCPs were two organic UV filters, i.e., 2-ethylhexyl-4-trimethoxycinnamate (EHMC) and octocrylene (OC), and two benzodiazepines (BZP), i.e., diazepam (DZP) and tetrazepam (TZP). Laboratory experiments were performed in which M. galloprovincialis was exposed to these compounds either directly from water, for the less lipophilic substances (BZP) or via spiked food for lipophilic UV filters. M. galloprovincialis uptook and eliminated BZP following first-order kinetics. The Biological Half-Life (t (1/2)) of TZP was 1.4 days, resulting in a bioconcentration factor of 64 and 99 mL g(-1) dry weight (dw), respectively, for 2.3 and 14.5 μg L(-1) of exposure, while the Biological Half-Life (t (1/2)) of DZP was 0.4 days, resulting in a bioconcentration factor of 51 mL g(-1) dw for 13.2 μg L(-1) of exposure. The uptake of UV filter was rapid in mussels, followed by elimination within 24 h. EHMC increased from 15 to 138 ng g(-1) dw in 1 h and decreased to 25 ng g(-1) after 24 h for 11.9 μg L(-1) exposure. OC reached 839 ng g(-1) dw after 1 h and decreased to 33 ng g(-1) after 24 h for 11.6 μg L(-1) exposure. However, EHMC and OC were slightly accumulated in 48 h, i.e., 38 and 60 ng g(-1) dw, respectively.

Anju Katyal - One of the best experts on this subject based on the ideXlab platform.

  • poly ethylene glycol conjugated solid lipid nanoparticles of noscapine improve Biological half life brain delivery and efficacy in glioblastoma cells
    Nanomedicine: Nanotechnology Biology and Medicine, 2013
    Co-Authors: Jitender Madan, Ravi Shankar Pandey, Vikas Jain, Om Prakash Katare, Ramesh Chandra, Anju Katyal
    Abstract:

    Abstract Noscapine crosses blood–brain-barrier and inhibits proliferation of glioblastoma cells. However, short plasma Half-Life and rapid elimination necessitate the administration of multiple injections for successive chemotherapy. Noscapine bearing solid lipid nanoparticles, Nos-SLN and poly (ethylene)-glycol conjugated solid lipid nanoparticles of noscapine, Nos-PEG-SLN of 61.3 ± 9.3-nm and 80.5 ± 8.9-nm containing 80.4 ± 3.2% and 83.6 ± 1.2% of Nos, were constructed. First order kinetic and Higuchi equation were followed to release the Nos at intracellular pH ~ 4.5. Further, a decrease in IC 50 (Nos; 40.5 μM > Nos-SLN; 27.2 μM > 20.8 μM) and enhanced subG1 population were observed in U87cells. Plasma Half-Life was enhanced up to ~ 11-fold and ~ 5-fold by Nos-PEG-SLN and Nos-SLN which significantly (P  From the Clinical Editor This report describes a possible approach to regulate the administration of multiple injections of Noscapine using solid lipid nanoparticles. The data warrant further in vivo tumor regression studies for optimal management of glioblastoma, a generally very poorly treatable brain cancer.

Sanjay Singh - One of the best experts on this subject based on the ideXlab platform.

  • trans resveratrol loaded dspe peg 2000 coated liposomes an evidence for prolonged systemic circulation and passive brain targeting
    Journal of Drug Delivery Science and Technology, 2016
    Co-Authors: Mahalingam Rajamanickam Vijayakumar, Ramoji Kosuru, Parameswara Rao Vuddanda, Sanjay Singh, Sanjay Kumar Singh
    Abstract:

    Abstract Trans resveratrol (RSV) is a natural molecule proved for cardioprotective effects, vasodilation, anti-inflammatory, cancer preventive and therapeutic activities devoid of any potential side effects. Recently, anti cancer potential against glioma cells were also reported with proven molecular mechanisms. However, the therapeutic application of RSV in clinical disease management is restricted because of its rapid elimination from systemic circulation and thereby low Biological half life in mammals. Therefore, the main objective of this study was to improve the systemic circulation and Biological half life of RSV using DSPE PEG 2000 decorated (PEGylated) liposomes. Moreover, brain distribution of RSV loaded PEGylated liposomes (RSV-PEG-Lipo) and non-PEGylated liposomes (RSV-Lipo) was also evaluated for proving their passive brain targeting ability. In vitro drug release of both liposomes was found to be sustained up to 48 h. RSV-PEG-Lipo showed higher area under the curve, plasma half life and mean residence time and lower volume of distribution and clearance than that of pristine RSV solution and RSV-Lipo. Pharmaokinetics results clearly indicated that the RSV-PEG-Lipo will be promising tool for enhancing plasma half life and prolong the systemic circulation of RSV. Brain distribution studies revealed that the liposomal formulations can be applied as an effective tool for passive brain targeting useful in the treatment of glioma.

  • intravenous administration of trans resveratrol loaded tpgs coated solid lipid nanoparticles for prolonged systemic circulation passive brain targeting and improved in vitro cytotoxicity against c6 glioma cell lines
    RSC Advances, 2016
    Co-Authors: Mahalingam Rajamanickam Vijayakumar, Parameswara Rao Vuddanda, Lakshmi Kumari, Krishna Kumar Patel, Kiran Yellappa Vajanthri, Sanjeev Kumar Mahto, Sanjay Singh
    Abstract:

    trans-Resveratrol (RSV), a natural molecule isolated from red wine, is widely known for several therapeutic potentials. RSV is proved for cardioprotective, vasodilation, anti-inflammatory, and anticancer effects. Recently, anticancer potential against glioma cells has also been reported. However, the clinical application of RSV in glioma treatment is largely limited because of its rapid metabolism and elimination from systemic circulation thereby exhibiting low Biological Half-Life and poor brain distribution as well. Therefore, the main objective of this study was to enhance the circulation time, Biological Half-Life and passive brain targeting of RSV using D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS)-coated solid lipid nanoparticles (RSV-TPGS-SLN). RSV-TPGS-SLN formulations were prepared by a solvent emulsification evaporation method and evaluated for several nanoparticulate characteristics. In vitro anticancer potential and cellular internalization of nanoparticles were also investigated in C6 glioma cell lines. Pharmacokinetics and biodistribution studies were carried out following intravenous administration in healthy Charles Foster rats. RSV-TPGS-SLN showed significantly higher in vitro cytotoxicity against C6 glioma cell lines and excellent cellular internalization. RSV-TPGS-SLN showed 11.12 and 9.37 times higher area under the curve and plasma Half-Life than RSV solution, respectively. Moreover, brain distribution of RSV-TPGS-SLN was found to be 9.23 times higher in comparison to that of RSV alone. Thus, we anticipate that the RSV-TPGS-SLN formulation can be applied as a potential tool for improving circulation time, Biological Half-Life and passive brain targeting of RSV, thereby being immensely useful in the treatment of glioma.