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Sample records for mice pharmacokinetic studies

  1. Chimeric mice with humanized liver: Application in drug metabolism and pharmacokinetics studies for drug discovery.

    Science.gov (United States)

    Naritomi, Yoichi; Sanoh, Seigo; Ohta, Shigeru

    2018-02-01

    Predicting human drug metabolism and pharmacokinetics (PK) is key to drug discovery. In particular, it is important to predict human PK, metabolite profiles and drug-drug interactions (DDIs). Various methods have been used for such predictions, including in vitro metabolic studies using human biological samples, such as hepatic microsomes and hepatocytes, and in vivo studies using experimental animals. However, prediction studies using these methods are often inconclusive due to discrepancies between in vitro and in vivo results, and interspecies differences in drug metabolism. Further, the prediction methods have changed from qualitative to quantitative to solve these issues. Chimeric mice with humanized liver have been developed, in which mouse liver cells are mostly replaced with human hepatocytes. Since human drug metabolizing enzymes are expressed in the liver of these mice, they are regarded as suitable models for mimicking the drug metabolism and PK observed in humans; therefore, these mice are useful for predicting human drug metabolism and PK. In this review, we discuss the current state, issues, and future directions of predicting human drug metabolism and PK using chimeric mice with humanized liver in drug discovery. Copyright © 2017 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  2. Pharmacokinetics study of Zr-89-labeled melanin nanoparticle in iron-overload mice

    International Nuclear Information System (INIS)

    Zhang, Pengjun; Yue, Yuanyuan; Pan, Donghui; Yang, Runlin; Xu, Yuping; Wang, Lizhen; Yan, Junjie; Li, Xiaotian; Yang, Min

    2016-01-01

    Melanin, a natural biological pigment present in many organisms, has been found to exhibit multiple functions. An important property of melanin is its ability to chelate metal ions strongly, which might be developed as an iron chelator for iron overload therapy. Herein, we prepared the ultrasmall water-soluble melanin nanoparticle (MP) and firstly evaluate the pharmacokinetics of MP in iron-overload mice to provide scientific basis for treating iron-overload. To study the circulation time and biodistribution, MP was labeled with 89 Zr, a long half-life (78.4 h) positron-emitting metal which is suited for the labeling of nanoparticles and large bioactive molecule. MP was chelated with 89 Zr directly at pH 5, resulting in non-decay-corrected yield of 89.6% and a radiochemical purity of more than 98%. The specific activity was at least190 MBq/μmol. The 89 Zr-MP was stable in human plasma and PBS for at least 48 h. The half-life of 89 Zr-MP was about 15.70 ± 1.74 h in iron-overload mice. Biodistribution studies and MicroPET imaging showed that 89 Zr-MP mainly accumulated in liver and spleen, which are the target organ of iron-overload. The results indicate that the melanin nanoparticle is promising for further iron overload therapy.

  3. Nicotinamide pharmacokinetics in humans and mice

    International Nuclear Information System (INIS)

    Horsman, M.R.; Hoyer, M.; Overgaard, J.; Honess, D.J.; Dennis, A.F.

    1993-01-01

    Healthy human volunteers orally ingested escalating doses of up to 6 g nicotinamide in capsule form on an empty stomach. Some side-effects were seen although these were mild and transient. HPLC analysis of blood samples showed peak plasma levels, typically within 45 min after ingestion, which were linearly dependent on dose ingested. The elimination half-life and AUC were also found to increase with drug dose, although these increases were non-linear. Pharmacokinetic studies were also performed to female CDF1 mice with C3H mammary carcinomas grown in the right rear foot. Analysis of blood and tumour samples taken from mice injected i.p. with nicotinamide doses between 100-1000 mg/kg showed similar characteristics as the human data, although the elimination half-lives were not dose-dependent. The average peak plasma concentration of 160 μg/ml measured in humans after taking 6 g of nicotinamide was equivalent to that seen in mice after injecting 171 mg/kg. Using a regrowth delay assay the enhancement of radiation damage by nicotinamide in this mouse tumour was found to be independent of drug dose from 100-1000 mg/kg, resulting in a constant 1.3-fold increase in radiation response. Doses of nicotinamide that can be tolerated clinically should therefore produce adequate enhancements of radiation damage in human tumours. (author)

  4. Biodistribution and pharmacokinetic studies of a porphyrin dimer photosensitizer (Oxdime) by fluorescence imaging and spectroscopy in mice bearing xenograft tumors.

    Science.gov (United States)

    Khurana, Mamta; Ulrich, Sébastien; Kim, Anthony; Moriyama, Yumi; Netchev, George; Akens, Margarete K; Anderson, Harry L; Wilson, Brian C

    2012-01-01

    Herein, we present a study of the pharmacokinetics and biodistribution of a butadiyne-linked conjugated porphyrin dimer (Oxdime) designed to have high near-infrared (NIR) 2-photon absorption cross-section for photodynamic therapy (PDT). Changes in biodistribution over time were monitored in mice carrying B16-F10 melanoma xenografts, following intravenous injection. Using fluorescence imaging of live animals and analyzing isolated organs ex vivo at different time points between 30 min and 24 h after injection, accumulation of Oxdime was measured in several organs (heart, kidney and liver) and in tumor. The concentration in the plasma was about 5-10 times higher than in other tissues. The fluorescence signal peaked at 3-12 h after injection in most tissues, including the tumor and the plasma. The change in the fluorescence emission spectrum of the sensitizer over time was also monitored and a shift in the maximum from 800 to 740 nm was observed over 24 h, showing that the Oxdime is metabolized. Significant quantities accumulated in the tumor, indicating that this PDT sensitizer may be promising for cancer treatment. © 2012 Wiley Periodicals, Inc. Photochemistry and Photobiology © 2012 The American Society of Photobiology.

  5. Pharmacokinetic of antimony in mice with cutaneous Leishmaniasis

    International Nuclear Information System (INIS)

    Borborema, Samanta E.T.; Nascimento, Nanci do; Osso Junior, Joao A.

    2007-01-01

    Cutaneous Leishmaniasis (CL) remains a major world health problem, with about 1.5 million new cases each year. Caused by protozoa Leishmania, in South America, this infection can vary from a chronic skin ulcer, to an erosive mucosal disease and severe facial disfigurement. Pentavalent antimony (Sb +5 ) as sodium stibogluconate (Pentostam) or meglumine antimoniate (Glucantime) are main drugs for treating most forms of human leishmaniasis. For six decades, despite the recent developments, the effective therapy to cutaneous leishmaniasis has been based on long parenteral courses of such drugs, even though these are fairly costly, toxic and inconvenient to use, without adequate knowledge on their pharmacokinetics or mechanism of action. Pharmacokinetics studies could be based on bioactive traceable drugs, usually with radioactive isotopes, but antimony radioisotopes are unavailable commercially. Neutron irradiation is a powerful tool in the analysis of mineral content of samples, for antimony, there are at least two main isotopes that could be formed after neutron irradiation in nuclear reactor. The aim of the present study was to construct antimony salts with those radioisotopes to obtain tracers to compare the pharmacokinetic and the tissue distribution of neutron irradiated meglumine antimoniate in healthy and cutaneous leishmaniasis experimentally infected mice. Meglumine antimoniate, (Glucantime, Aventis, S.P, Brazil), was neutron irradiated inside the IEA-R1 nuclear reactor (IPEN/CNEN-SP), producing two radioisotopes 122 Sb and 124 Sb. Its biodistribution was verified in BALB/c mice experimentally infected with Leishmania (Leishmania) Amazonensis, which received a single intraperitoneal dose of the drug. At different times after injection, the tissues and blood were excised and activity measured in a NaI (Tl) scintillation counter. Compared with the healthy mice, experimentally infected mice had significantly lower maximum concentration of antimony and high

  6. Pharmacokinetic of antimony in mice with cutaneous Leishmaniasis

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta E.T.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mails: samanta@usp.br; nnascime@ipen.br; Andrade Junior, Heitor F. de [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Lab. de Biologia Molecular; Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil); E-mail: hfandrad@usp.br; Osso Junior, Joao A. [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Centro de Radiofarmacia]. E-mail: jaosso@ipen.br

    2007-07-01

    Cutaneous Leishmaniasis (CL) remains a major world health problem, with about 1.5 million new cases each year. Caused by protozoa Leishmania, in South America, this infection can vary from a chronic skin ulcer, to an erosive mucosal disease and severe facial disfigurement. Pentavalent antimony (Sb{sup +5}) as sodium stibogluconate (Pentostam) or meglumine antimoniate (Glucantime) are main drugs for treating most forms of human leishmaniasis. For six decades, despite the recent developments, the effective therapy to cutaneous leishmaniasis has been based on long parenteral courses of such drugs, even though these are fairly costly, toxic and inconvenient to use, without adequate knowledge on their pharmacokinetics or mechanism of action. Pharmacokinetics studies could be based on bioactive traceable drugs, usually with radioactive isotopes, but antimony radioisotopes are unavailable commercially. Neutron irradiation is a powerful tool in the analysis of mineral content of samples, for antimony, there are at least two main isotopes that could be formed after neutron irradiation in nuclear reactor. The aim of the present study was to construct antimony salts with those radioisotopes to obtain tracers to compare the pharmacokinetic and the tissue distribution of neutron irradiated meglumine antimoniate in healthy and cutaneous leishmaniasis experimentally infected mice. Meglumine antimoniate, (Glucantime, Aventis, S.P, Brazil), was neutron irradiated inside the IEA-R1 nuclear reactor (IPEN/CNEN-SP), producing two radioisotopes {sup 122}Sb and {sup 124}Sb. Its biodistribution was verified in BALB/c mice experimentally infected with Leishmania (Leishmania) Amazonensis, which received a single intraperitoneal dose of the drug. At different times after injection, the tissues and blood were excised and activity measured in a NaI (Tl) scintillation counter. Compared with the healthy mice, experimentally infected mice had significantly lower maximum concentration of antimony

  7. Pharmacokinetic study of radiolabeled anti-colorectal carcinoma monoclonal antibodies in tumor-bearing nude mice

    Energy Technology Data Exchange (ETDEWEB)

    Douillard, J.Y.; Chatal, J.F.; Curtet, C.; Kremer, M.; Saccavini, J.C.; Peuvrel, P.; Koprowski, H.

    1985-09-01

    Monoclonal antibodies (MoAbs) 17-1A and 19-9, which specifically bind human colorectal carcinoma (CRC) cells, were tested for their usefulness in localizing colorectal tumors in nude mice. One of the /sup 131/I-labeled MoAbs and an irrelevant /sup 125/I-labeled immunoglobulin of the same isotype were injected into nude mice simultaneously bearing a human CRC and a human melanoma. The percentage of the injected dose of antibody per gram of tissue, the CRC/tissue ratios of antibody distribution, and the localization indicees were calculated at various time intervals (2 h to 10 days). For both MoAbs, labeling to a specific activity of 10 ..mu..Ci/..mu..g by the iodogen method gave optimum immunoreactivity. The accumulation of MoAb 17-1A in CRC reached its maximum at 5 days and remained at this level for up to 9 days postinjection. For MoAb 19-9, which detects a circulating antigen shed by the tumor into the serum, the accumulation in the CRC was maximum at 24 h, and decreased thereafter. The CRC/organ ratios and localization indices for-both MoAbs increased with time in the CRC tissue, but remained low and unchanged in the melanoma and normal tissue. Using F(ab')/sub 2/ antibody fragments, faster kinetics with earlier maximum accumulation, higher tumor/organ ratios, and better localization indices were achieved than with intact MoAbs. The data obtained was useful in defining parameters which must be considered before radiolabeled MoAbs are used in cancer patients for diagnostic purposes.

  8. Albendazole nanocrystals with improved pharmacokinetic performance in mice.

    Science.gov (United States)

    Paredes, Alejandro J; Bruni, Sergio Sánchez; Allemandi, Daniel; Lanusse, Carlos; Palma, Santiago D

    2018-02-01

    Albendazole (ABZ) is a broad-spectrum antiparasitic agent with poor aqueous solubility, which leads to poor/erratic bioavailability and therapeutic failures. Here, we aimed to produce a novel formulation of ABZ nanocrystals (ABZNC) and assess its pharmacokinetic performance in mice. Results/methodology: ABZNC were prepared by high-pressure homogenization and spray-drying processes. Redispersion capacity and solid yield were measured in order to obtain an optimized product. The final particle size was 415.69±7.40 nm and the solid yield was 72.32%. The pharmacokinetic parameters obtained in a mice model for ABZNC were enhanced (p < 0.05) with respect to the control formulation. ABZNC with improved pharmacokinetic behavior were produced by a simple, inexpensive and potentially scalable methodology.

  9. Pharmacokinetics and pharmacodynamics of SCT800, a new recombinant FVIII, in hemophilia A mice

    Science.gov (United States)

    Gu, Ruo-lan; Liu, Liang; Xie, Liang-zhi; Gai, Wen-lin; Cao, Si-shuo; Meng, Zhi-yun; Gan, Hui; Wu, Zhuo-na; Li, Jian; Zheng, Ying; Zhu, Xiao-xia; Dou, Gui-fang

    2016-01-01

    Aim: SCT800 is a new third-generation recombinant FVIII agent that is undergoing promising preclinical study. This study aimed to investigate the pharmacokinetic and pharmacodynamic profiles of SCT800 in hemophilia A mice. Methods: After hemophilia A mice were intravenously injected with single dose of SCT800 (80, 180, and 280 IU/kg) or the commercially available product Xyntha (280 IU/kg), pharmacokinetics profiles were evaluated based on measuring plasma FVIII: C. For pharmacodynamics study, dose-response curves of SCT800 and Xyntha (1–200 IU/kg) were constructed using a tail bleeding model monitoring both bleeding time and blood loss. Results: Pharmacokinetics profile analysis showed a dose independency of SCT800 ranging from 80 to 280 IU/kg and comparable pharmacokinetic profiles between SCT800 and Xyntha at the doses tested. Pharmacodynamics study revealed comparable ED50 values of SCT800 and Xyntha in the tail bleeding model: 14.78 and 15.81 IU/kg for bleeding time, respectively; 13.50 and 13.58 IU/kg for blood loss, respectively. Moreover, at the doses tested, the accompanying dose-related safety evaluation in the tail bleeding model showed lower hypercoagulable tendency and wider dosage range potential for SCT800 than Xyntha. Conclusion: In hemophilia A mice, SCT800 shows comparable pharmacokinetics and pharmacodynamics to Xyntha at the doses tested, and possibly with better safety properties. PMID:26806305

  10. Biodistribution, pharmacokinetic, and imaging studies with 186Re-labeled NR-LU-10 whole antibody in LS174T colonic tumor-bearing mice

    International Nuclear Information System (INIS)

    Goldrosen, M.H.; Biddle, W.C.; Pancook, J.; Bakshi, S.; Vanderheyden, J.L.; Fritzberg, A.R.; Morgan, A.C. Jr.; Foon, K.A.

    1990-01-01

    Biodistribution, pharmacokinetic, and radioimaging studies were performed with 186Re-labeled NR-LU-10 whole antibody in athymic nude mice bearing the LS174T tumor growing either s.c. or in an experimental hepatic metastasis model. NR-LU-10 is an IgG2b murine monoclonal antibody (MAb) that reacts with virtually all human tumors of epithelial origin. NR-BC-1, a IgG2b murine MAb that reacts with normal human B-cell and B malignancies, was used as an isotype-matched control. These MAbs were radiolabeled with 186Re by a preformed chelate approach by using the triamide thiolate ligand system. 186Re-labeled NR-LU-10 (50 microCi) was injected into nude mice bearing LS174T tumors growing s.c. Biodistribution studies revealed that the LS174T tumor retained the highest concentration of 186Re-labeled NR-LU-10 at day 6. The tumor:blood ratio ranged from 0.1:1 to 10.8:1 by day 6, the last day of analysis. In contrast the tumor:blood ratio of 186Re-labeled NR-BC-1, the isotype-matched MAb control, was 1:1 on day 6. Pharmacokinetic analysis indicated that the t1/2 beta of NR-LU-10 for blood and other tissues ranged from 21 to 25 h, while the t1/2 beta for the LS174T tumor averaged 52 h. The area under the curve for tumor compared to blood was 2.8- to 5.7-fold higher than the area under the curve for all other tissues and organs. The mean residence time for NR-LU-10 in blood and all other organs ranged from 23 to 26 h, while the mean residence time for NR-LU-10 in the LS174T tumor was 72 h. Scintigraphic images revealed selective uptake of the 186Re-labeled NR-LU-10, but not of the 186Re-labeled NR-BC-1, at the LS174T tumor site. Studies in an experimental model of hepatic metastasis revealed a similar selective pattern of 186Re-labeled NR-LU-10 accumulation. Scintigraphic images of the LS174T tumor growing within the athymic nude mouse liver were obtained

  11. Gender differences in cocaine pharmacokinetics in CF-1 mice.

    Science.gov (United States)

    Visalli, Thomas; Turkall, Rita; Abdel-Rahman, Mohamed S

    2005-01-15

    Hepatocellular damage is thought to occur as a result of cytochrome P450-mediated oxidation of cocaine to norcocaine (NC), a precursor of the hepatotoxic nitrosonium ion. However, this damage occurs only in male mice, with females exhibiting minimal biochemical and histological signs of hepatocellular stress. The objective of this study was to determine the plasma time course and tissue disposition of cocaine and its metabolites to further investigate the role that metabolism may play in the gender difference observed. Male and female CF-1 mice were orally administered 20mg/kg cocaine hydrochloride once daily for 7 days. Blood samples were withdrawn at various time points post-injection and analyzed for cocaine and its metabolites benzoylecgonine (BE), norcocaine, ecgonine methyl ester (EME), and ecgonine (E). In addition, tissue concentrations of cocaine and its metabolites were determined in liver, heart, brain, and kidney tissue. The results demonstrated that the plasma elimination half-life of cocaine is nearly three times longer in males versus females. Non-hepatotoxic hydrolysis metabolites BE, EME, and E were higher in female tissues while norcocaine was detected in tissues of male animals only. This study revealed that differences in cocaine pharmacokinetics and the resultant differences in the biodisposition of cocaine and its metabolites in tissues contribute to the mechanism of gender difference seen in cocaine hepatotoxicity.

  12. Sensitive LC-MS/MS Method for the Simultaneous Determination of Bendamustine and its Active Metabolite, γ-Hydroxybendamustine in Small Volume Mice and Dog Plasma and its Application to a Pharmacokinetic Study in Mice and Dogs.

    Science.gov (United States)

    Chandrashekar, Devaraj V; Suresh, Ponnayyan S; Kumar, Rajnish; Bhamidipati, Ravi Kanth; Mullangi, Ramesh; Richter, Wolfgang; Srinivas, Nuggehally R

    2017-09-01

    A highly sensitive, specific and rapid LC-ESI-MS/MS method has been developed and validated for the simultaneous quantification of bendamustine (BM) and γ-hydroxybendamustine (HBM) in small volume (20 µL) mice and dog plasma using phenacetin as an internal standard (IS) as per regulatory guidelines. Both the analytes and IS were extracted from mice and dog plasma using a liquid-liquid extraction method. Chromatography was achieved on Atlantis dC 18 column using an isocratic mobile phase (0.2% formic acid:acetonitrile, 25:75) at a flow rate of 0.40 mL/min. The total chromatographic run time was 3.0 min and the elution of BM, HBM and IS occurred at ~1.2, 1.2 and 2.0 min, respectively. A linear response function was established 0.11-518 ng/mL for both the analytes in mice and dog plasma. The intra- and inter-day accuracy and precisions were in the range of 3.46-12.9 and 3.63-8.23%; 1.15-9.00 and 7.86-9.49% for BM and HBM, respectively in mice plasma and 2.15-6.49 and 1.73-13.1%; 4.35-13.9 and 4.33-10.5% for BM and HBM, respectively in dog plasma. This novel method has been applied to a pharmacokinetic study in mice and dogs. © Georg Thieme Verlag KG Stuttgart · New York.

  13. Pharmacokinetic Analysis of 64Cu-ATSM Dynamic PET in Human Xenograft Tumors in Mice

    DEFF Research Database (Denmark)

    Li, Fan; Jørgensen, Jesper Tranekjær; Madsen, Jacob

    2015-01-01

    The aim of this study was to evaluate the feasibility to perform voxel-wise kinetic modeling on datasets obtained from tumor-bearing mice that underwent dynamic PET scans with 64Cu-ATSM and extract useful physiological parameters.METHODS: Tumor-bearing mice underwent 90-min dynamic PET scans...... relevant parameters from voxel-wise pharmacokinetic analysis to be used for preclinical validation of 64Cu-ATSM as a hypoxia-specific PET tracer....

  14. Enhancement of curcumin oral absorption and pharmacokinetics of curcuminoids and curcumin metabolites in mice

    Science.gov (United States)

    Zhongfa, Liu; Chiu, Ming; Wang, Jiang; Chen, Wei; Yen, Winston; Fan-Havard, Patty; Yee, Lisa D.; Chan, Kenneth K.

    2012-01-01

    Purpose Curcumin has shown a variety of biological activity for various human diseases including cancer in preclinical setting. Its poor oral bioavailability poses significant pharmacological barriers to its clinical application. Here, we established a practical nano-emulsion curcumin (NEC) containing up to 20% curcumin (w/w) and conducted the pharmacokinetics of curcuminoids and curcumin metabolites in mice. Methods This high loading NEC was formulated based on the high solubility of curcumin in polyethylene glycols (PEGs) and the synergistic enhancement of curcumin absorption by PEGs and Cremophor EL. The pharmacokinetics of curcuminoids and curcumin metabolites was characterized in mice using a LC–MS/MS method, and the pharmacokinetic parameters were determined using WinNonlin computer software. Results A tenfold increase in the AUC0→24h and more than 40-fold increase in the Cmax in mice were observed after an oral dose of NEC compared with suspension curcumin in 1% methylcellulose. The plasma pharmacokinetics of its two natural congeners, demethoxycurcumin and bisdemethoxycurcumin, and three metabolites, tetrahydrocurcumin (THC), curcumin-O-glucuronide, and curcumin-O-sulfate, was characterized for the first time in mice after an oral dose of NEC. Conclusion This oral absorption enhanced NEC may provide a practical formulation to conduct the correlative study of the PK of curcuminoids and their pharmacodynamics, e.g., hypomethylation activity in vivo. PMID:21968952

  15. Development of a physiologically based pharmacokinetic model for bisphenol A in pregnant mice

    International Nuclear Information System (INIS)

    Kawamoto, Yuko; Matsuyama, Wakoto; Wada, Masahiro; Hishikawa, Junko; Chan, Melissa Pui Ling; Nakayama, Aki; Morisawa, Shinsuke

    2007-01-01

    Bisphenol A (BPA) is a weakly estrogenic monomer used to produce polymers for food contact and other applications, so there is potential for oral exposure of humans to trace amounts via ingestion. To date, no physiologically based pharmacokinetic (PBPK) model has been located for BPA in pregnant mice with or without fetuses. An estimate by a mathematical model is essential since information on humans is difficult to obtain experimentally. The PBPK model was constructed based on the pharmacokinetic data of our experiment following single oral administration of BPA to pregnant mice. The risk assessment of bisphenol A (BPA) on the development of human offspring is an important issue. There have been limited data on the exposure level of human fetuses to BPA (e.g. BPA concentration in cord blood) and no information is available on the pharmacokinetics of BPA in humans with or without fetuses. In the present study, we developed a physiologically based pharmacokinetic (PBPK) model describing the pharmacokinetics of BPA in a pregnant mouse with the prospect of future extrapolation to humans. The PBPK model was constructed based on the pharmacokinetic data of an experiment we executed on pregnant mice following single oral administration of BPA. The model could describe the rapid transfer of BPA through the placenta to the fetus and the slow disappearance from fetuses. The simulated time courses after three-time repeated oral administrations of BPA by the constructed model fitted well with the experimental data, and the simulation for the 10 times lower dose was also consistent with the experiment. This suggested that the PBPK model for BPA in pregnant mice was successfully verified and is highly promising for extrapolation to humans who are expected to be exposed more chronically to lower doses

  16. Changes in the pharmacokinetics of digoxin in polyuria in streptozotocin-induced diabetic mice and lithium carbonate-treated mice.

    Science.gov (United States)

    Ikarashi, Nobutomo; Kagami, Mai; Kobayashi, Yasushi; Ishii, Makoto; Toda, Takahiro; Ochiai, Wataru; Sugiyama, Kiyoshi

    2011-06-01

    In humans, digoxin is mainly eliminated through the kidneys unchanged, and renal clearance represents approximately 70% of the total clearance. In this study, we used the mouse models to examine digoxin pharmacokinetics in polyuria induced by diabetes mellitus and lithium carbonate (Li(2)CO(3)) administration, including mechanistic evaluation of the contribution of glomerular filtration, tubular secretion, and tubular reabsorption. After digoxin administration to streptozotocin (STZ)-induced diabetic mice, digoxin CL/F increased to approximately 2.2 times that in normal mice. After treatment with Li(2)CO(3) (0.2%) for 10 days, the CL/F increased approximately 1.1 times for normal mice and 1.6 times for STZ mice. Creatinine clearance (CLcr) and the renal mRNA expression levels of mdr1a did not differ significantly between the normal, STZ, and Li(2)CO(3)-treated mice. The urine volume of STZ mice was approximately 26 mL/day, 22 times that of normal mice. The urine volume of Li(2)CO(3)-treated mice increased approximately 7.3 times for normal mice and 2.3 times for STZ mice. These results suggest that the therapeutic effect of digoxin may be significantly reduced in the presence of polyuria either induced by diabetes mellitus or manifested as an adverse effect of Li(2)CO(3) in diabetic patients, along with increased urine volume.

  17. Pharmacokinetic studies of neuromuscular blocking agents: Good Clinical Research Practice (GCRP)

    DEFF Research Database (Denmark)

    Viby-Mogensen, J.; Østergaard, D.; Donati, F.

    2000-01-01

    Good Clinical Research Practice (GCRP), neuromuscular blocking agents, pharmacokinetics, pharmacokinetic/pharmacodynamic modeling, population pharmacokinetics, statistics, study design......Good Clinical Research Practice (GCRP), neuromuscular blocking agents, pharmacokinetics, pharmacokinetic/pharmacodynamic modeling, population pharmacokinetics, statistics, study design...

  18. Discriminative Stimulus Effects of 3,4-Methylenedioxymethamphetamine and Its Enantiomers in Mice: Pharmacokinetic Considerations

    OpenAIRE

    Fantegrossi, William E.; Murai, Naoki; Mathúna, Brian Ó.; Pizarro, Nieves; de la Torre, Rafael

    2009-01-01

    3,4-Methylenedioxymethamphetamine (MDMA) is a drug of abuse with mixed stimulant- and hallucinogen-like effects. The aims of the present studies were to establish discrimination of S(+)-MDMA, R(-)-MDMA, or their combination as racemic MDMA in separate groups of mice to assess cross-substitution tests among all three compounds, to determine the time courses of the training doses, to assess pharmacokinetic variables after single injections and after cumulative dosing, an...

  19. Comparative Pharmacokinetics of Perfluorononanoic acid in Rats and Mice*.

    Science.gov (United States)

    Perfluorononanoic acid (PFNA), a member of the perfluoroalkyl acids (PFAAs) is found at low concentrations in the environment, but is also detectable in humans and wildlife. Previous studies have examined the pharmacokinetics (PK) of lower carbon-chain PFAAs, such as perfluorobut...

  20. Species differences in methanol and formic acid pharmacokinetics in mice, rabbits and primates

    International Nuclear Information System (INIS)

    Sweeting, J. Nicole; Siu, Michelle; McCallum, Gordon P.; Miller, Lutfiya; Wells, Peter G.

    2010-01-01

    Methanol (MeOH) is metabolized primarily by alcohol dehydrogenase in humans, but by catalase in rodents, with species variations in the pharmacokinetics of its formic acid (FA) metabolite. The teratogenic potential of MeOH in humans is unknown, and its teratogenicity in rodents may not accurately reflect human developmental risk due to differential species metabolism, as for some other teratogens. To determine if human MeOH metabolism might be better reflected in rabbits than rodents, the plasma pharmacokinetics of MeOH and FA were compared in male CD-1 mice, New Zealand white rabbits and cynomolgus monkeys over time (24, 48 and 6 h, respectively) following a single intraperitoneal injection of 0.5 or 2 g/kg MeOH or its saline vehicle. Following the high dose, MeOH exhibited saturated elimination kinetics in all 3 species, with similar peak concentrations and a 2.5-fold higher clearance in mice than rabbits. FA accumulation within 6 h in primates was 5-fold and 43-fold higher than in rabbits and mice respectively, with accumulation being 10-fold higher in rabbits than mice. Over 48 h, FA accumulation was nearly 5-fold higher in rabbits than mice. Low-dose MeOH in mice and rabbits resulted in similarly saturated MeOH elimination in both species, but with approximately 2-fold higher clearance rates in mice. FA accumulation was 3.8-fold higher in rabbits than mice. Rabbits more closely than mice reflected primates for in vivo MeOH metabolism, and particularly FA accumulation, suggesting that developmental studies in rabbits may be useful for assessing potential human teratological risk.

  1. Investigation of the Influence of Protein-Losing Enteropathy on Monoclonal Antibody Pharmacokinetics in Mice.

    Science.gov (United States)

    Yang, Yujie; Li, Tommy R; Balthasar, Joseph P

    2017-11-01

    Protein losing enteropathy (PLE), which is characterized by substantial loss of plasma proteins into the gastrointestinal (GI) tract, is a complication of a variety of GI diseases, including inflammatory bowel disease. Clinical studies have found that the clearance of monoclonal antibodies (mAb) is often increased in subjects with diseases known to cause PLE; however, direct relationships between PLE and mAb pharmacokinetics have not been demonstrated. This study employed a murine model of colitis to examine the influence of PLE on mAb pharmacokinetics. Mice were given dextran sodium sulfate (DSS, 2% w/v) supplemented tap water as drinking source for 6 days to induce colitis and PLE. Mice were then intravenously injected with 8C2, a murine IgG1 mAb. 8C2 plasma concentrations were measured up to 14 days post injection. Fecal alpha-1-antitrypsin (A1AT) clearance was measured as biomarker for PLE. DSS-treated mice developed PLE of clinically relevant severity. They also showed a transient increase in 8C2 plasma clearance and a decrease in 8C2 plasma exposure. The area under the 8C2 plasma concentration-time curve for the length of the study (AUC 0-14d ) reduced from 1368 ± 255 to 594 ± 224 day μg/ml following DSS treatment (p = 0.001). A quantitative relationship between A1AT clearance and 8C2 clearance was obtained via population pharmacokinetic modeling. DSS treatment substantially increased 8C2 clearance and reduced 8C2 exposure. Increased mAb plasma clearance was highly correlated with A1AT fecal clearance, suggesting the possible utility of A1AT fecal clearance as a mechanistic biomarker to predict the pharmacokinetics of therapeutic antibodies.

  2. Metabolic profiles of pomalidomide in human plasma simulated with pharmacokinetic data in control and humanized-liver mice.

    Science.gov (United States)

    Shimizu, Makiko; Suemizu, Hiroshi; Mitsui, Marina; Shibata, Norio; Guengerich, F Peter; Yamazaki, Hiroshi

    2017-10-01

    1. Pomalidomide has been shown to be potentially teratogenic in thalidomide-sensitive animal species such as rabbits. Screening for thalidomide analogs devoid of teratogenicity/toxicity - attributable to metabolites formed by cytochrome P450 enzymes - but having immunomodulatory properties is a strategic pathway towards development of new anticancer drugs. 2. In this study, plasma concentrations of pomalidomide, its primary 5-hydroxylated metabolite, and its glucuronide conjugate(s) were investigated in control and humanized-liver mice. Following oral administration of pomalidomide (100 mg/kg), plasma concentrations of 7-hydroxypomalidomide and 5-hydroxypomalidomide glucuronide were slightly higher in humanized-liver mice than in control mice. 3. Simulations of human plasma concentrations of pomalidomide were achieved with simplified physiologically-based pharmacokinetic models in both groups of mice in accordance with reported pomalidomide concentrations after low dose administration in humans. 4. The results indicate that pharmacokinetic profiles of pomalidomide were roughly similar between control mice and humanized-liver mice and that control and humanized-liver mice mediated pomalidomide 5-hydroxylation in vivo. Introducing one aromatic amino group into thalidomide resulted in less species differences in in vivo pharmacokinetics in control and humanized-liver mice.

  3. Comparison of predictability for human pharmacokinetics parameters among monkeys, rats, and chimeric mice with humanised liver.

    Science.gov (United States)

    Miyamoto, Maki; Iwasaki, Shinji; Chisaki, Ikumi; Nakagawa, Sayaka; Amano, Nobuyuki; Hirabayashi, Hideki

    2017-12-01

    1. The aim of the present study was to evaluate the usefulness of chimeric mice with humanised liver (PXB mice) for the prediction of clearance (CL t ) and volume of distribution at steady state (Vd ss ), in comparison with monkeys, which have been reported as a reliable model for human pharmacokinetics (PK) prediction, and with rats, as a conventional PK model. 2. CL t and Vd ss values in PXB mice, monkeys and rats were determined following intravenous administration of 30 compounds known to be mainly eliminated in humans via the hepatic metabolism by various drug-metabolising enzymes. Using single-species allometric scaling, human CL t and Vd ss values were predicted from the three animal models. 3. Predicted CL t values from PXB mice exhibited the highest predictability: 25 for PXB mice, 21 for monkeys and 14 for rats were predicted within a three-fold range of actual values among 30 compounds. For predicted human Vd ss values, the number of compounds falling within a three-fold range was 23 for PXB mice, 24 for monkeys, and 16 for rats among 29 compounds. PXB mice indicated a higher predictability for CL t and Vd ss values than the other animal models. 4. These results demonstrate the utility of PXB mice in predicting human PK parameters.

  4. Biodistribution and pharmacokinetic of 1E10 monoclonal antibody after subcutaneous administration in healthy mice

    International Nuclear Information System (INIS)

    León, M; Hernández, I; Aldana, L; Ayra, F; Castro, Y; Leyva, R; García, L; Casaco, A

    2016-01-01

    To evaluate biodistribution and pharmacokinetic of the 1E10, the molecule was radio labelled with 125I and incorporated into a cold antibody formulation. Isotopic labeling was carried out by means of standardized methods.Introduction:1E10 monoclonal antibody was developed at Centre of Molecular Immunology (CIM) as antitumoral drug with proved efficacy in experimental models. In the present investigation, biodistribution and pharmacokinetic studies were conducted with the help of radio isotopic labeling. Materials and methods: 1E10 was supplied by CIM and labeled with 125I by the iodogen method. To male Balb/c mice from CENPALAB a single subcutaneous administration of 1 mg/kg was performed in the supra scapular region and accommodated in metabolic cages during experiments. Blood samples were taken alternating five groups of three animals according with a sparse data design. Biodistribution was carried out by direct organ sampling and radioactive counting. Pharmacokinetic was performed by compartmental analysis. Urine and faces were collected at regular time intervals. Results: Observed pharmacokinetic behaviour is typical of an immunoglobulin in the assay system used, showing a slow clearance and a small volume of distribution. Biodistribution shows no preference for any sampled organs or tissues. Only a high relative uptake was observed in axillary and brachial lymph nodes close to administration site. (author)

  5. Effect of anions or foods on absolute bioavailability of calcium from calcium salts in mice by pharmacokinetics

    OpenAIRE

    Zenei Taira, Zenei; Ueda,Yukari

    2013-01-01

    Yukari Ueda, Zenei TairaFaculty of Pharmaceutical Sciences, Tokushima Bunri University, Tokushima, JapanAbstract: We studied the absolute bioavailability of calcium from calcium L-lactate in mice using pharmacokinetics, and reviewed the absolute bioavailability of calcium from three other calcium salts in mice previously studied: calcium chloride, calcium acetate, and calcium ascorbate. The results showed that calcium metabolism is linear between intravenous administration of 15 mg/kg and 30 ...

  6. Pharmacokinetic of 3 H-deacetylasperulosidic acid in mice

    Directory of Open Access Journals (Sweden)

    Simla Basar-Maurer

    2016-08-01

    Full Text Available Background: An investigation was conducted to determine the fate of the iridoid derivative deacetylasperulosidic acid (DAA after oral application to mice. Methods: DAA was extracted from Morinda citrifolia leaf and purified by preparative HPLC. The identity was verified by MS and NMR spectroscopy. A sample of DAA was radioactively labelled with tritium and applied to mice by gavage. The pharmacokinetic of the radioactivity was investigated in blood, organs, urine and feces. Metabolites were isolated in blood and urine by HPLC and identified by LC-MS. In vitro incubation of DAA with mouse duodenum and liver homogenate and human fecal bacteria was performed and possible metabolites were separated by HPLC. Results: DAA was rapidly absorbed and excreted mainly via the kidneys with a half-life of 30 minutes. Radioactivity was present in all organs with highest concentrations in kidney and liver. Almost 100% of the radioactivity isolated from urine and organs could be identified as unchanged DAA. Additionally, no metabolism could be observed after in vitro incubation of DAA with mouse small intestine or liver homogenate. However, a total breakdown of the molecule was observed after incubation of DAA with human intestinal bacteria. Conclusion: The absorption and excretion of glycosides such as DAA in mammals without hydrolysis is a potential defense mechanism of animals against the toxicity of these compounds.

  7. Time-dependent pharmacokinetics of dexamethasone and its efficacy in human breast cancer xenograft mice: a semi-mechanism-based pharmacokinetic/pharmacodynamic model.

    Science.gov (United States)

    Li, Jian; Chen, Rong; Yao, Qing-Yu; Liu, Sheng-Jun; Tian, Xiu-Yun; Hao, Chun-Yi; Lu, Wei; Zhou, Tian-Yan

    2018-03-01

    Dexamethasone (DEX) is the substrate of CYP3A. However, the activity of CYP3A could be induced by DEX when DEX was persistently administered, resulting in auto-induction and time-dependent pharmacokinetics (pharmacokinetics with time-dependent clearance) of DEX. In this study we investigated the pharmacokinetic profiles of DEX after single or multiple doses in human breast cancer xenograft nude mice and established a semi-mechanism-based pharmacokinetic/pharmacodynamic (PK/PD) model for characterizing the time-dependent PK of DEX as well as its anti-cancer effect. The mice were orally given a single or multiple doses (8 mg/kg) of DEX, and the plasma concentrations of DEX were assessed using LC-MS/MS. Tumor volumes were recorded daily. Based on the experimental data, a two-compartment model with first order absorption and time-dependent clearance was established, and the time-dependence of clearance was modeled by a sigmoid E max equation. Moreover, a semi-mechanism-based PK/PD model was developed, in which the auto-induction effect of DEX on its metabolizing enzyme CYP3A was integrated and drug potency was described using an E max equation. The PK/PD model was further used to predict the drug efficacy when the auto-induction effect was or was not considered, which further revealed the necessity of adding the auto-induction effect into the final PK/PD model. This study established a semi-mechanism-based PK/PD model for characterizing the time-dependent pharmacokinetics of DEX and its anti-cancer effect in breast cancer xenograft mice. The model may serve as a reference for DEX dose adjustments or optimization in future preclinical or clinical studies.

  8. Pharmacokinetics of Sustained-Release Analgesics in Mice

    Science.gov (United States)

    Kendall, Lon V; Hansen, Ryan J; Dorsey, Kathryn; Kang, Sooah; Lunghofer, Paul J; Gustafson, Daniel L

    2014-01-01

    Buprenorphine and carprofen, 2 of the most commonly used analgesics in mice, must be administered every 8 to 12 h to provide sustained analgesia. Sustained-release (SR) formulations of analgesics maintain plasma levels that should be sufficient to provide sustained analgesia yet require less frequent dosing and thus less handling of and stress to the animals. The pharmacokinetics of SR formulations of buprenorphine (Bup-SR), butorphanol (Butp-SR), fentanyl (Fent-SR), carprofen (Carp-SR), and meloxicam (Melox-SR) were evaluated in mice over 72 h and compared with those of traditional, nonSR formulations. Bup-SR provided plasma drug levels greater than the therapeutic level for the first 24 to 48 h after administration, but plasma levels of Bup-HCl fell below the therapeutic level by 4 h. Fent-SR maintained plasma levels greater than reported therapeutic levels for 12 h. Therapeutic levels of the remaining drugs are unknown, but Carp-SR provided plasma drug levels similar to those of Carp for the first 24 h after administration, whereas Melox-SR had greater plasma levels than did Melox for the first 8 h. Butp-SR provided detectable plasma drug levels for the first 24 h, with a dramatic decrease over the first 4 h. These results indicate that Bup-SR provides a stable plasma drug level adequate for analgesia for 24 to 48 h after administration, whereas Carp-SR, Melox-SR, Fent-SR, and Butp-SR would require additional doses to provide analgesic plasma levels beyond 24 h in mice. PMID:25255070

  9. Preclinical acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of ["1"8F]fluorocholine in mice

    International Nuclear Information System (INIS)

    Silveira, Marina B.; Ferreira, Soraya M.Z.M.D.; Nascimento, Leonardo T.C.; Costa, Flávia M.; Mendes, Bruno M.; Ferreira, Andrea V.; Malamut, Carlos; Silva, Juliana B.; Mamede, Marcelo

    2016-01-01

    ["1"8F]Fluorocholine (["1"8F]FCH) has been proven to be effective in prostate cancer. Since ["1"8F]FCH is classified as a new radiopharmaceutical in Brazil, preclinical safety and efficacy data are required to support clinical trials and to obtain its approval. The aim of this work was to perform acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of ["1"8F]FCH. The results could support its use in nuclear medicine as an important piece of work for regulatory in Brazil. - Highlights: • Data demonstrated the high quality, safety and effectiveness of ["1"8F]FCH. • ["1"8F]FCH preclinical profile is in accordance with previously published. • Toxicity, distribution, kinetics and radiation dosimetry were well characterized. • The results are important for regulatory issues in Brazil and other countries.

  10. Pharmacokinetics and effects on serum cholinesterase activities of organophosphorus pesticides acephate and chlorpyrifos in chimeric mice transplanted with human hepatocytes.

    Science.gov (United States)

    Suemizu, Hiroshi; Sota, Shigeto; Kuronuma, Miyuki; Shimizu, Makiko; Yamazaki, Hiroshi

    2014-11-01

    Organophosphorus pesticides acephate and chlorpyrifos in foods have potential to impact human health. The aim of the current study was to investigate the pharmacokinetics of acephate and chlorpyrifos orally administered at lowest-observed-adverse-effect-level doses in chimeric mice transplanted with human hepatocytes. Absorbed acephate and its metabolite methamidophos were detected in serum from wild type mice and chimeric mice orally administered 150mg/kg. Approximately 70% inhibition of cholinesterase was evident in plasma of chimeric mice with humanized liver (which have higher serum cholinesterase activities than wild type mice) 1day after oral administrations of acephate. Adjusted animal biomonitoring equivalents from chimeric mice studies were scaled to human biomonitoring equivalents using known species allometric scaling factors and in vitro metabolic clearance data with a simple physiologically based pharmacokinetic (PBPK) model. Estimated plasma concentrations of acephate and chlorpyrifos in humans were consistent with reported concentrations. Acephate cleared similarly in humans and chimeric mice but accidental/incidental overdose levels of chlorpyrifos cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in mice. The data presented here illustrate how chimeric mice transplanted with human hepatocytes in combination with a simple PBPK model can assist evaluations of toxicological potential of organophosphorus pesticides. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Pharmacokinetics and Differential Regulation of Cytochrome P450 Enzymes in Type 1 Allergic Mice.

    Science.gov (United States)

    Tanino, Tadatoshi; Komada, Akira; Ueda, Koji; Bando, Toru; Nojiri, Yukie; Ueda, Yukari; Sakurai, Eiichi

    2016-12-01

    Type 1 allergic diseases are characterized by elevated production of specific immunoglobulin E (IgE) for each antigen and have become a significant health problem worldwide. This study investigated the effect of IgE-mediated allergy on drug pharmacokinetics. To further understand differential suppression of hepatic cytochrome P450 (P450) activity, we examined the inhibitory effect of nitric oxide (NO), a marker of allergic conditions. Seven days after primary sensitization (PS7) or secondary sensitization (SS7), hepatic CYP1A2, CYP2C, CYP2E1, and CYP3A activities were decreased to 45%-75% of the corresponding control; however, CYP2D activity was not downregulated. PS7 and SS7 did not change the expression levels of five P450 proteins. Disappearance of CYP1A2 and CYP2D substrates from the plasma was not significantly different between allergic mice and control mice. In contrast, the area under the curve of a CYP1A2-mediated metabolite in PS7 and SS7 mice was reduced by 50% of control values. Total clearances of a CYP2E1 substrate in PS7 and SS7 mice were significantly decreased to 70% and 50% respectively, of the control without altering plasma protein binding. Hepatic amounts of CYP1A2 and CYP2E1 substrates were enhanced by allergic induction, being responsible for each downregulated activity. NO scavenger treatment completely improved the downregulated P450 activities. Therefore, our data suggest that the onset of IgE-mediated allergy alters the pharmacokinetics of major P450-metabolic capacity-limited drugs except for CYP2D drugs. NO is highly expected to participate in regulatory mechanisms of the four P450 isoforms. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  12. Pharmacological activities and pharmacokinetic study of hyperoside ...

    African Journals Online (AJOL)

    Studies on its pharmacokinetic (PK) properties revealed that it is a stable compound ... attention in drug discovery and food supplement research ... neurotrophic factor (BDNF) and cAMP response element ... antidepressant effect of hyperoside is mediated through .... Saposhnikovia divaricata by high performance counter-.

  13. Radiosynthesis and pharmacokinetics of [18F]fluoroethyl bufalin in hepatocellular carcinoma-bearing mice

    Directory of Open Access Journals (Sweden)

    Yang Z

    2017-01-01

    Full Text Available Zhaoshuo Yang,1 Jianhua Liu,2 Qingqing Huang,3 Zhouji Zhang,1 Jiawei Zhang,1 Yanjia Pan,1 Yunke Yang,1 Dengfeng Cheng4 1Department of Chinese Traditional Medicine, Zhongshan Hospital, Fudan University, 2School of Medicine, Shanghai Jiao Tong University, 3Department of Nuclear Medicine, Shanghai 10th People’s Hospital, Tongji University School of Medicine, 4Department of Nuclear Medicine, Zhongshan Hospital, Fudan University, Shanghai, People’s Republic of China Purpose: Bufalin, the main component of a Chinese traditional medicine chansu, shows convincing anticancer effects in a lot of tumor cell lines. However, its in vivo behavior is still unclear. This research aimed to evaluate how bufalin was dynamically absorbed after intravenous injection in animal models. We developed a radiosynthesis method of [18F]fluoroethyl bufalin to noninvasively evaluate the tissue biodistribution and pharmacokinetics in hepatocellular carcinoma-bearing mice. Methods: [18F]fluoroethyl bufalin was synthesized with conjugation of 18F-CH2CH2OTs and bufalin. The radiochemical purity was proved by the radio-high-performance liquid chromatography (HPLC. The pharmacokinetic studies of [18F]fluoroethyl bufalin were then performed in Institute of Cancer Research (ICR mice. Furthermore, the biodistribution and metabolism of [18F]fluoroethyl bufalin in HepG2 and SMMC-7721 tumor-bearing nude mice were studied in vivo by micro-positron emission tomography (micro-PET. Results: The radiochemical purity (RCP of [18F]fluoroethyl bufalin confirmed by radio-HPLC was 99%±0.18%, and [18F]fluoroethyl bufalin showed good in vitro and in vivo stabilities. Blood dynamics of [18F]fluoroethyl bufalin conformed to the two compartments in the ICR mice model. The pharmacokinetic parameters of [18F]fluoroethyl bufalin were calculated by DAS 2.0 software. The area under concentration–time curve (AUC0–t and the values of clearance (CL were 540.137 µg/L·min and 0.001

  14. Bioavailability and pharmacokinetics of the cardioprotecting flavonoid 7-monohydroxyethylrutoside in mice.

    NARCIS (Netherlands)

    Hassan, MA Abou El; Kedde, MA; Zwiers, UT; Tourn, E; Haenen, GR; Vijgh, van der W.J.F.

    2003-01-01

    PURPOSE: The pharmacokinetics and bioavailability of monoHER, a promising protector against doxorubicin-induced cardiotoxicity, were determined after different routes of administration. METHODS: Mice were treated with 500 mg.kg(-1) monoHER intraperitoneally (i.p.), subcutaneously (s.c.) or

  15. The pharmacokinetics and metabolism of lumiracoxib in chimeric humanized and murinized FRG mice.

    Science.gov (United States)

    Dickie, A P; Wilson, C E; Schreiter, K; Wehr, R; Wilson, E M; Bial, J; Scheer, N; Wilson, I D; Riley, R J

    2017-07-01

    The pharmacokinetics and metabolism of lumiracoxib were studied, after administration of single 10mg/kg oral doses to chimeric liver-humanized and murinized FRG mice. In the chimeric humanized mice, lumiracoxib reached peak observed concentrations in the blood of 1.10±0.08μg/mL at 0.25-0.5h post-dose with an AUC inf of 1.74±0.52μgh/mL and an effective half-life for the drug of 1.42±0.72h (n=3). In the case of the murinized animals peak observed concentrations in the blood were determined as 1.15±0.08μg/mL at 0.25h post-dose with an AUC inf of 1.94±0.22μgh/mL and an effective half-life of 1.28±0.02h (n=3). Analysis of blood indicated only the presence of unchanged lumiracoxib. Metabolic profiling of urine, bile and faecal extracts revealed a complex pattern of metabolites for both humanized and murinized animals with, in addition to unchanged parent drug, a variety of hydroxylated and conjugated metabolites detected. The profiles obtained in humanized mice were different compared to murinized animals with e.g., a higher proportion of the dose detected in the form of acyl glucuronide metabolites and much reduced amounts of taurine conjugates. Comparison of the metabolic profiles obtained from the present study with previously published data from C57bl/6J mice and humans, revealed a greater though not complete match between chimeric humanized mice and humans, such that the liver-humanized FRG model may represent a useful approach to assessing the biotransformation of such compounds in humans. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Pharmacokinetic studies on the hepatotoxicity of luteoskyrin, 1. Intracellular distribution of radioactivity in the liver of mice administered /sup 3/H-luteoskyrin

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, I [Tokyo Univ. (Japan). Inst. for Medical Science; Hayashi, T; Ueno, Y

    1974-08-01

    Intracellular distribution of the radioactivity derived from /sup 3/H-luteoskyrin in mouse liver was investigated. It was revealed that luteoskyrin has a high affinity to mitochondria and cell debris of mouse liver cells. This characteristic distribution pattern in the liver cells may be responsible for the mitochondrial impairment and the age and sex differences in the susceptibility of mice to this mycotoxin. (auth)

  17. Lack of Exposure in a First-in-Man Study Due to Aldehyde Oxidase Metabolism: Investigated by Use of 14C-microdose, Humanized Mice, Monkey Pharmacokinetics, and In Vitro Methods.

    Science.gov (United States)

    Jensen, Klaus Gjervig; Jacobsen, Anne-Marie; Bundgaard, Christoffer; Nilausen, Dorrit Østergaard; Thale, Zia; Chandrasena, Gamini; Jørgensen, Martin

    2017-01-01

    Inclusion of a microdose of 14 C-labeled drug in the first-in-man study of new investigational drugs and subsequent analysis by accelerator mass spectrometry has become an integrated part of drug development at Lundbeck. It has been found to be highly informative with regard to investigations of the routes and rates of excretion of the drug and the human metabolite profiles according to metabolites in safety testing guidance and also when additional metabolism-related issues needed to be addressed. In the first-in-man study with the NCE Lu AF09535, contrary to anticipated, surprisingly low exposure was observed when measuring the parent compound using conventional bioanalysis. Parallel accelerator mass spectrometry analysis revealed that the low exposure was almost exclusively attributable to extensive metabolism. The metabolism observed in humans was mediated via a human specific metabolic pathway, whereas an equivalent extent of metabolism was not observed in preclinical species. In vitro, incubation studies in human liver cytosol revealed involvement of aldehyde oxidase (AO) in the biotransformation of Lu AF09535. In vivo, substantially lower plasma exposure of Lu AF09535 was observed in chimeric mice with humanized livers compared with control animals. In addition, Lu AF09535 exhibited very low oral bioavailability in monkeys despite relatively low clearance after intravenous administration in contrast to the pharmacokinetics in rats and dogs, both showing low clearance and high bioavailability. The in vitro and in vivo methods applied were proved useful for identifying and evaluating AO-dependent metabolism. Different strategies to integrate these methods for prediction of in vivo human clearance of AO substrates were evaluated. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  18. Chimeric mice transplanted with human hepatocytes as a model for prediction of human drug metabolism and pharmacokinetics.

    Science.gov (United States)

    Sanoh, Seigo; Ohta, Shigeru

    2014-03-01

    Preclinical studies in animal models are used routinely during drug development, but species differences of pharmacokinetics (PK) between animals and humans have to be taken into account in interpreting the results. Human hepatocytes are also widely used to examine metabolic activities mediated by cytochrome P450 (P450) and other enzymes, but such in vitro metabolic studies also have limitations. Recently, chimeric mice with humanized liver (h-chimeric mice), generated by transplantation of human donor hepatocytes, have been developed as a model for the prediction of metabolism and PK in humans, using both in vitro and in vivo approaches. The expression of human-specific metabolic enzymes and metabolic activities was confirmed in humanized liver of h-chimeric mice with high replacement ratios, and several reports indicate that the profiles of P450 and non-P450 metabolism in these mice adequately reflect those in humans. Further, the combined use of h-chimeric mice and r-chimeric mice, in which endogenous hepatocytes are replaced with rat hepatocytes, is a promising approach for evaluation of species differences in drug metabolism. Recent work has shown that data obtained in h-chimeric mice enable the semi-quantitative prediction of not only metabolites, but also PK parameters, such as hepatic clearance, of drug candidates in humans, although some limitations remain because of differences in the metabolic activities, hepatic blood flow and liver structure between humans and mice. In addition, fresh h-hepatocytes can be isolated reproducibly from h-chimeric mice for metabolic studies. Copyright © 2013 John Wiley & Sons, Ltd.

  19. Biodistribution, pharmacokinetics, and toxicity of dendrimer-coated iron oxide nanoparticles in BALB/c mice

    Directory of Open Access Journals (Sweden)

    Salimi M

    2018-03-01

    Full Text Available Marzieh Salimi,1,2 Saeed Sarkar,1,2 Samaneh Fathi,3 Ali Mohammad Alizadeh,4 Reza Saber,2,3 Fatemeh Moradi,5 Hamid Delavari6 1Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran; 2Research Center of Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran, Iran; 3Department of Medical Nanotechnology, Tehran University of Medical Sciences, Tehran, Iran; 4Cancer Research Center, Tehran University of Medical Sciences, Tehran, Iran; 5Department of Medical Physiology, Tehran University of Medical Sciences, Tehran, Iran; 6Department of Materials Science and Engineering, Tarbiat Modares University, Tehran, Iran Background: The possibility of using a specific nanoparticle in nanomedicine highly depends on its biodistribution profile and biocompatibility. Due to growing demand for iron oxide nanoparticles (IONPs and dendrimers in biomedical applications, this study was performed to assess the biodistribution, pharmacokinetics, and toxicity of dendrimer-coated iron oxide nanoparticles (G4@IONPs. Materials and methods: IONPs were synthesized via co-precipitation and coated with the fourth generation (G4 of polyamidoamine (PAMAM dendrimer. To determine the biodistribution, 5 mg/mL G4@IONPs suspension was intraperitoneally injected into tumor-bearing BALB/c mice, and iron levels in blood and various organs, including the lung, liver, brain, heart, tumor, and kidney, were measured by inductively coupled plasma mass spectrometry (ICP-MS at 4, 8, 12, and 24 h after injection. Also, to investigate the toxicity of G4@IONPs, different concentrations of G4@IONPs were injected into BALB/c mice, and blood, renal, and hepatic factors were measured. Furthermore, histopathological staining was performed to investigate the effect of G4@IONPs on the liver and kidney tissues. Results: The results showed that the iron content was higher in the kidney, liver, and lung tissues 24 h after

  20. Sunitinib-ibuprofen drug interaction affects the pharmacokinetics and tissue distribution of sunitinib to brain, liver, and kidney in male and female mice differently.

    Science.gov (United States)

    Lau, Christine Li Ling; Chan, Sook Tyng; Selvaratanam, Manimegahlai; Khoo, Hui Wen; Lim, Adeline Yi Ling; Modamio, Pilar; Mariño, Eduardo L; Segarra, Ignacio

    2015-08-01

    Tyrosine kinase inhibitor sunitinib (used in GIST, advanced RCC, and pancreatic neuroendocrine tumors) undergoes CYP3A4 metabolism and is an ABCB1B and ABCG2 efflux transporters substrate. We assessed the pharmacokinetic interaction with ibuprofen (an NSAID used by patients with cancer) in Balb/c male and female mice. Mice (study group) were coadministered (30 min apart) 30 mg/kg of ibuprofen and 60 mg/kg of sunitinib PO and compared with the control groups, which received sunitinib alone (60 mg/kg, PO). Sunitinib concentration in plasma, brain, kidney, and liver was measured by HPLC as scheduled and noncompartmental pharmacokinetic parameters estimated. In female control mice, sunitinib AUC0→∞ decreased in plasma (P brain (P male control mice. After ibuprofen coadministration, female mice showed lower AUC0→∞ in plasma (P brain, liver, and kidney (all P male mice, AUC0→∞ remained unchanged in plasma, increased in liver and kidney, and decreased in brain (all P male and female control mice, but changed after ibuprofen coadministration: Male mice showed 1.6-fold higher liver-to-plasma ratio (P female mice and in kidney (male and female mice) but decreased 55% in brain (P differences. The results illustrate the relevance of this DDI on sunitinib pharmacokinetics and tissue uptake. These may be due to gender-based P450 and efflux/transporters differences. © 2015 Société Française de Pharmacologie et de Thérapeutique.

  1. Proposed mechanistic description of dose-dependent BDE-47 urinary elimination in mice using a physiologically based pharmacokinetic model

    Energy Technology Data Exchange (ETDEWEB)

    Emond, Claude, E-mail: claude.emond@umontreal.ca [BioSimulation Consulting Inc., Newark, DE (United States); Departments of Environmental and Occupational Health, Medicine Faculty, University of Montreal, Montreal, Quebec (Canada); Sanders, J. Michael, E-mail: sander10@mail.nih.gov [National Cancer Institute, Research Triangle Park, NC (United States); Wikoff, Daniele, E-mail: dwikoff@toxstrategies.com [ToxStrategies, Austin, TX (United States); Birnbaum, Linda S., E-mail: birnbaumls@niehs.nih.gov [National Cancer Institute, Research Triangle Park, NC (United States)

    2013-12-01

    Polybrominated diphenyl ethers (PBDEs) have been used in a wide variety of consumer applications as additive flame retardants. In North America, scientists have noted continuing increases in the levels of PBDE congeners measured in human serum. Some recent studies have found that PBDEs are associated with adverse health effects in humans, in experimental animals, and wildlife. This laboratory previously demonstrated that urinary elimination of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) is saturable at high doses in mice; however, this dose-dependent urinary elimination has not been observed in adult rats or immature mice. Thus, the primary objective of this study was to examine the mechanism of urinary elimination of BDE-47 in adult mice using a physiologically based pharmacokinetic (PBPK) model. To support this objective, additional laboratory data were collected to evaluate the predictions of the PBPK model using novel information from adult multi-drug resistance 1a/b knockout mice. Using the PBPK model, the roles of mouse major urinary protein (a blood protein carrier) and P-glycoprotein (an apical membrane transporter in proximal tubule cells in the kidneys, brain, intestines, and liver) were investigated in BDE-47 elimination. The resulting model and new data supported the major role of m-MUP in excretion of BDE-47 in the urine of adult mice, and a lesser role of P-gp as a transporter of BDE-47 in mice. This work expands the knowledge of BDE-47 kinetics between species and provides information for determining the relevancy of these data for human risk assessment purposes. - Highlights: • We report the first study on PBPK model on flame retardant in mice for BDE-47. • We examine mechanism of urinary elimination of BDE-47 in mice using a PBPK model. • We investigated roles of m-MUP and P-gp as transporters in urinary elimination.

  2. Extensive metabolism and route-dependent pharmacokinetics of bisphenol A (BPA) in neonatal mice following oral or subcutaneous administration

    International Nuclear Information System (INIS)

    Draganov, Dragomir I.; Markham, Dan A.; Beyer, Dieter; Waechter, John M.; Dimond, Stephen S.; Budinsky, Robert A.; Shiotsuka, Ronald N.; Snyder, Stephanie A.; Ehman, Kimberly D.; Hentges, Steven G.

    2015-01-01

    Orally administered bisphenol A (BPA) undergoes efficient first-pass metabolism to produce the inactive conjugates BPA-glucuronide (BPA-G) and BPA-sulfate (BPA-S). This study was conducted to evaluate the pharmacokinetics of BPA, BPA-G and BPA-S in neonatal mice following the administration of a single oral or subcutaneous (SC) dose. This study consisted of 3 phases: (1) mass-balance phase in which effective dose delivery procedures for oral or SC administration of 3 H-BPA to postnatal day three (PND3) mice were developed; (2) pharmacokinetic phase during which systemic exposure to total 3 H-BPA-derived radioactivity in female PND3 mice was established; and (3) metabolite profiling phase in which 50 female PND3 pups received either a single oral or SC dose of 3 H-BPA. Blood was collected from 5 pups/route/time-point at various times post-dosing, the blood plasma samples were pooled by group, and time-point and samples were profiled by HPLC with fraction collection. Fractions were analyzed for total radioactivity and data used to reconstruct radiochromatograms and to integrate individual peaks. The identity of the BPA, BPA-G, and BPA-S peaks was confirmed using authentic standards and LC–MS/MS analysis. The result of this study revealed that female PND3 mice have the capacity to metabolize BPA to BPA-G, BPA-S and other metabolites after both routes of administration. Systemic exposure to free BPA is route-dependent as the plasma concentrations were lower following oral administration compared to SC injection

  3. [Pharmacokinetics and relative bioavailability of THC and THC-solid dispersion orally to mice at single dose].

    Science.gov (United States)

    Liao, Li; Hua, Hua; Zhao, Jun-Ning; Luo, Heng; Yang, An-Dong

    2014-03-01

    To establish a fast sensitive, reproducible LC-MS/MS method to study pharmacokinetic properties of THC, and compare relative bioavailability of THC and its solid dispersion in mice. 200 mice were divided randomly into two groups, and administered orally with THC and THC-solid dispersion after fasting (calculate on THC:400 mg x kg(-1)), used HPLC-MS/MS method to determine the THC concentration of each period at the following times: baseline ( predose ), 15, 30, 45 min, 1, 1.5, 2, 3, 4, 6, 24 h after dosing. Calculating the pharmacokinetic parameters according to the C-t curv, and then use the Phoenix WinNonlin software for data analysis. The calibration curves were linear over the range 9.06-972 microg x L(-1) for THC (R2 = 0.999). The limit of detection (LOD) was 0.7 microg x L(-1), respectively. The average extraction recoveries for THC was above 75%, The methodology recoveries were between 79% and 108%. The intra-day and inter-day RSD were less than 13%, the stability test showed that the plasma samples was stable under different conditions (RSD THC and THC-solid dispersion orally to mice shows as fllows: T(max), were 60 and 15 min, AUC(0-t) were 44 500.43 and 57 497.81 mg x L(-1) x min, AUC(0-infinity) were 51 226.00 and 68 031.48 mg x L(-1) x min, MRT(0-infinity) were 596.915 6, 661.747 7 min, CL(z)/F were 0.007 809 and 0.005 88 L x min(-1) x kg(-1). Compared with THC, the MRT and t1/2 of the THC-solid dispersion were all slightly extended, the t(max) was significantly reduced, AUC(0-24 h), AUC(0-infinity) and C(max) were all significantly higher, the relative bioavailability of THC-solid dispersion is 1.34 times of THC. The results of the experiment shows that the precision, accuracy, recovery and applicability were found to be adequate for the pharmacokinetic studies. After oral administration to mice, the relative bioavailability of THC-solid dispersion show significant improvement compared to THC.

  4. Identification and Pharmacokinetics of Multiple Potential Bioactive Constituents after Oral Administration of Radix Astragali on Cyclophosphamide-Induced Immunosuppression in Balb/c Mice

    Directory of Open Access Journals (Sweden)

    Menghua Liu

    2015-03-01

    Full Text Available Radix Astragali (RA is one of the commonly-used traditional Chinese medicines (TCMs with an immunomodulatory effect confirmed in the clinic. In order to better understand the material basis for the therapeutic effects, this study was to investigate the absorbed components and their pharmacokinetic profile after oral administration of RA on cyclophosphamide-induced immunosuppression in Balb/c mice. As a result, 51 compounds in RA extract and 31 prototype compounds with nine metabolites were detected in mice plasma by the ultra-fast liquid chromatography (UFLC-DAD-Q-TOF-MS/MS method. The pharmacokinetic parameters of five main constituents, including calycosin-7-O-glucoside, ononin, calycosin, formononetin and astragaloside IV, were obtained using HPLC-MS/MS. These results offered useful information for research on the pharmacological mechanism of RA and for its further development.

  5. [Discussion about traditional Chinese medicine pharmacokinetics study based on first botanical drug approved by FDA].

    Science.gov (United States)

    Huang, Fanghua

    2010-04-01

    Pharmacokinetics study is one of main components of pharmaceuticals development. Food and Drug Administration (FDA) approved Veregen as the first botanical drug in 2006. This article introduced FDA's requirement on pharmacokinetics study of botanical drug and pharmacokinetics studies of Veregen, summarized current requirement and status quo of pharmacokinetics study on traditional Chinese medicine (TCM) and natural medicine in China, and discussed about pharmacokinetics study strategy for TCM and natural medicine.

  6. Human plasma metabolic profiles of benzydamine, a flavin-containing monooxygenase probe substrate, simulated with pharmacokinetic data from control and humanized-liver mice.

    Science.gov (United States)

    Yamazaki-Nishioka, Miho; Shimizu, Makiko; Suemizu, Hiroshi; Nishiwaki, Megumi; Mitsui, Marina; Yamazaki, Hiroshi

    2018-02-01

    1. Benzydamine is used clinically as a nonsteroidal anti-inflammatory drug in oral rinses and is employed in preclinical research as a flavin-containing monooxygenase (FMO) probe substrate. In this study, plasma concentrations of benzydamine and its primary N-oxide and N-demethylated metabolites were investigated in control TK-NOG mice, in humanized-liver mice, and in mice whose liver cells had been ablated with ganciclovir. 2. Following oral administration of benzydamine (10 mg/kg) in humanized-liver TK-NOG mice, plasma concentrations of benzydamine N-oxide were slightly higher than those of demethyl benzydamine. In contrast, in control and ganciclovir-treated TK-NOG mice, concentrations of demethyl benzydamine were slightly higher than those of benzydamine N-oxide. 3. Simulations of human plasma concentrations of benzydamine and its N-oxide were achieved using simplified physiologically based pharmacokinetic models based on data from control TK-NOG mice and from reported benzydamine concentrations after low-dose administration in humans. Estimated clearance rates based on data from humanized-liver and ganciclovir-treated TK-NOG mice were two orders magnitude high. 4. The pharmacokinetic profiles of benzydamine were different for control and humanized-liver TK-NOG mice. Humanized-liver mice are generally accepted human models; however, drug oxidation in mouse kidney might need to be considered when probe substrates undergo FMO-dependent drug oxidation in mouse liver and kidney.

  7. Using Dried Blood Spot Sampling to Improve Data Quality and Reduce Animal Use in Mouse Pharmacokinetic Studies

    Science.gov (United States)

    Wickremsinhe, Enaksha R; Perkins, Everett J

    2015-01-01

    Traditional pharmacokinetic analysis in nonclinical studies is based on the concentration of a test compound in plasma and requires approximately 100 to 200 µL blood collected per time point. However, the total blood volume of mice limits the number of samples that can be collected from an individual animal—often to a single collection per mouse—thus necessitating dosing multiple mice to generate a pharmacokinetic profile in a sparse-sampling design. Compared with traditional methods, dried blood spot (DBS) analysis requires smaller volumes of blood (15 to 20 µL), thus supporting serial blood sampling and the generation of a complete pharmacokinetic profile from a single mouse. Here we compare plasma-derived data with DBS-derived data, explain how to adopt DBS sampling to support discovery mouse studies, and describe how to generate pharmacokinetic and pharmacodynamic data from a single mouse. Executing novel study designs that use DBS enhances the ability to identify and streamline better drug candidates during drug discovery. Implementing DBS sampling can reduce the number of mice needed in a drug discovery program. In addition, the simplicity of DBS sampling and the smaller numbers of mice needed translate to decreased study costs. Overall, DBS sampling is consistent with 3Rs principles by achieving reductions in the number of animals used, decreased restraint-associated stress, improved data quality, direct comparison of interanimal variability, and the generation of multiple endpoints from a single study. PMID:25836959

  8. Pharmacokinetics and Pharmacodynamics of a 13-mer LNA-inhibitor-miR-221 in Mice and Non-human Primates

    Directory of Open Access Journals (Sweden)

    Maria Eugenia Gallo Cantafio

    2016-01-01

    Full Text Available Locked nucleic acid (LNA oligonucleotides have been successfully used to efficiently inhibit endogenous small noncoding RNAs in vitro and in vivo. We previously demonstrated that the direct miR-221 inhibition by the novel 13-mer LNA-i-miR-221 induces significant antimyeloma activity and upregulates canonical miR-221 targets in vitro and in vivo. To evaluate the LNA-i-miR-221 pharmacokinetics and pharmacodynamics, novel assays for oligonucleotides quantification in NOD.SCID mice and Cynomolgus monkeys (Macaca fascicularis plasma, urine and tissues were developed. To this aim, a liquid chromatography/mass spectrometry method, after solid-phase extraction, was used for the detection of LNA-i-miR-221 in plasma and urine, while a specific in situ hybridization assay for tissue uptake analysis was designed. Our analysis revealed short half-life, optimal tissue biovailability and minimal urine excretion of LNA-i-miR-221 in mice and monkeys. Up to 3 weeks, LNA-i-miR-221 was still detectable in mice vital organs and in xenografted tumors, together with p27 target upregulation. Importantly, no toxicity in the pilot monkey study was observed. Overall, our findings indicate the suitability of LNA-i-miR-221 for clinical use and we provide here pilot data for safety analysis and further development of LNA-miRNA-based therapeutics for human cancer.

  9. Sex-Specific Effects of Chronic Fluoxetine Treatment on Neuroplasticity and Pharmacokinetics in Mice

    OpenAIRE

    Hodes, Georgia E.; Hill-Smith, Tiffany E.; Suckow, Raymond F.; Cooper, Thomas B.; Lucki, Irwin

    2010-01-01

    Neurogenesis is a mechanism through which antidepressants may produce therapeutic effects. There is a dearth of information regarding the effects of antidepressants on neurogenesis and neurotrophin mobilization in females. This study examined sex differences in the alteration of cell proliferation and survival in multiple regions of the brain. Additional experiments examined brain-derived neurotrophic factor (BDNF) levels and pharmacokinetics of fluoxetine to determine whether they mediate se...

  10. Pharmacokinetics and tissue distribution of five active ingredients of Eucommiae cortex in normal and ovariectomized mice by UHPLC-MS/MS.

    Science.gov (United States)

    An, Jing; Hu, Fangdi; Wang, Changhong; Zhang, Zijia; Yang, Li; Wang, Zhengtao

    2016-09-01

    1. Pinoresinol di-O-β-d-glucopyranoside (PDG), geniposide (GE), geniposidic acid (GA), aucubin (AN) and chlorogenic acid (CA) are the representative active ingredients in Eucommiae cortex (EC), which may be estrogenic. 2. The ultra high-performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS) method for simultaneous determination of the five ingredients showed good linearity, low limits of quantification and high extraction recoveries, as well as acceptable precision, accuracy and stability in mice plasma and tissue samples (liver, spleen, kidney and uterus). It was successfully applied to the comparative study on pharmacokinetics and tissue distribution of PDG, GE, GA, AN and CA between normal and ovariectomized (OVX) mice. 3. The results indicated that except CA, the plasma and tissue concentrations of PDG, GE, GA in OVX mice were all greater than those in normal mice. AN could only be detected in the plasma and liver homogenate of normal mice, which was poorly absorbed in OVX mice and low in other measured tissues. PDG, GE and GA seem to be better absorbed in OVX mice than in normal mice proved by the remarkable increased value of AUC0-∞ and Cmax. It is beneficial that PDG, GE, GA have better plasma absorption and tissue distribution in pathological state.

  11. Aqueous stability and oral pharmacokinetics of meloxicam and carprofen in male C57BL/6 mice.

    Science.gov (United States)

    Ingrao, Joelle C; Johnson, Ron; Tor, Elizabeth; Gu, Yu; Litman, Marcus; Turner, Patricia V

    2013-09-01

    We found that carprofen and meloxicam under 3 environmental conditions (ambient dark, ambient light, and 4 °C) remained stable for at least 7 d. We then evaluated the oral pharmacokinetics of meloxicam (20 mg/kg) and carprofen (10 mg/kg) in male C57BL/6 mice after oral gavage or administration in the drinking water. Mice did not drink meloxicam-medicated water but readily consumed carprofen-medicated water, consuming an average of 14.19 mL carprofen-medicated water per 100 g body weight daily; mice drank more during the dark phase than during the light phase. Plasma analyzed by HPLC (meloxicam) and tandem mass spectrometry (carprofen) revealed that the peak meloxicam and carprofen concentrations were 16.7 and 20.3 μg/mL and occurred at 4 and 2 h after oral gavage, respectively. Similar blood levels were achieved after 12 h access to the carprofen-medicated water bottle. At 24 h after oral gavage, the drugs were not detectable in plasma. Meloxicam plasma AUC, elimination half-life, apparent volume of distribution, and apparent oral clearance were 160.4 mg/L × h, 7.4 h, 0.36 L/kg, and 0.125 mL/h × kg, respectively. Carprofen plasma AUC, elimination half-life, apparent volume of distribution, and apparent oral clearance were 160.8 mg/L × h, 7.4 h, 0.42 L/kg, and 0.062 mL/h × kg, respectively. No gross or microscopic evidence of toxicity was seen in any mouse. Our findings indicate that carprofen can be administered in drinking water to mice and that medicated water bottles should be placed 12 to 24 h prior to painful procedures.

  12. Radioimmunotherapy for liver micrometastases in mice. Pharmacokinetics, dose estimation, and long-term effect

    International Nuclear Information System (INIS)

    Saga, Tsuneo; Sakahara, Harumi; Nakamoto, Yuji; Sato, Noriko; Zhao, Songji; Iida, Yasuhiko; Konishi, Junji; Kuroki, Masahide; Endo, Keigo

    1999-01-01

    The pharmacokinetics of a therapeutic dose of 131 I-labeled antibody and the absorbed dose in liver micrometastases of human colon cancer LS174T in female BALB/c nu/nu mice were investigated, along with the long-term therapeutic effect. Mice with liver micrometastases were given an intravenous injection of 131 I-labeled anti-carcinoembryonic antigen (CEA) antibody F33-104 (8.88 MBq/40 μg). The biodistribution of the antibody was determined 1, 2, 4, 6, and 10 days later. The absorbed dose was estimated for three hypothetical tumor diameters; 1,000, 500, and 300 μm. Autoradiography showed a homogeneous distribution of radioactivity in the micrometastases, and a high uptake was maintained until day 6 (24.0% injected dose (ID)/g on day 1 to 17.8% ID/g on day 6), but decreased thereafter. The absorbed doses in the 1,000-, 500-, and 300-μm tumors were calculated to be 19.1, 12.0, and 8.2 Gy, respectively. The intravenous injection of the 131 I-labeled antibody also showed a dose-dependent therapeutic effect (all mice of the nontreated group died, with a mean survival period of 4 weeks; 3 of the 8 mice that received 9.25 MBq survived up to 120 days with no sign of liver metastasis). These data give further evidence that micrometastasis is a good target of radioimmunotherapy, and that an absorbed dose of less than 20 Gy can effectively control small metastatic lesions. (author)

  13. In vivo pharmacokinetic study comparing different methodologies for labelling of Annexin V

    International Nuclear Information System (INIS)

    Santos, Josefina da Silva; Pujatti, Priscilla Brunelli; Couto, Renata Martinussi; Araujo, Elaine Bortoleti de Araujo

    2008-01-01

    In this work we preliminary results of the evaluation of the influence of the chelating in the pharmacokinetics of ANXA5 radiolabeled with technetium-99m in Swiss mice and using HYNIC and EC as bifunctional chelators are showed

  14. Pharmacokinetics and tissue distribution of recombinant human tumor necrosis factor-alpha in mice

    International Nuclear Information System (INIS)

    Ferraiolo, B.L.; Moore, J.A.; Crase, D.; Gribling, P.; Wilking, H.; Baughman, R.A.

    1988-01-01

    The serum pharmacokinetics and the major organs of accumulation of recombinant human tumor necrosis factor-alpha (rHuTNF) were determined in BDF1 mice after intravenous and intramuscular administration. Serum concentrations of immunoreactive protein were determined by enzyme-linked immunosorbent assay, and radioactivity was quantitated by beta and gamma scintigraphy. The serum pharmacokinetics of labeled and unlabeled rHuTNF were identical when administered by the intravenous route. After intravenous doses of 165 to 320 micrograms/kg, the clearance was 2.9-3.6 ml/hr, the initial volume of distribution was 1.4-1.6 ml (70-80 ml/kg), and the half-life was 18.5-19.2 min. Intramuscular administration of 320 micrograms/kg resulted in a peak serum concentration of 112 ng/ml. The time of the peak concentration was 1 hr, and the bioavailability of the intramuscular dose was 12%. The data suggest that the disposition of this protein may be biexponential. If this is the case, the terminal phase would appear to account for less than 1% of the total AUC. Since serum concentrations in the terminal phase are at the sensitivity limit of the assay, a single half-life is reported. 125I-Labeled and metabolically labeled 3H-rHuTNF were used to examine tissue distribution. After intravenous 125I-rHuTNF administration, the rank order of accumulation of the 125I-radiolabel in the major organs (per cent dose per organ over 1440 min) was: liver greater than kidney greater than lung greater than heart greater than spleen. This rank order of accumulation was confirmed by intravenous 3H-rHuTNF administration

  15. Pharmacokinetics and biodistribution of Erufosine in nude mice - implications for combination with radiotherapy

    International Nuclear Information System (INIS)

    Henke, Guido; Jendrossek, Verena; Lindner, Lars H; Vogeser, Michael; Eibl, Hans-Jörg; Wörner, Jürgen; Müller, Arndt C; Bamberg, Michael; Wachholz, Kirsten; Belka, Claus

    2009-01-01

    Alkylphosphocholines represent promising antineoplastic drugs that induce cell death in tumor cells by primary interaction with the cell membrane. Recently we could show that a combination of radiotherapy with Erufosine, a paradigmatic intravenously applicable alkylphosphocholine, in vitro leads to a clear increase of irradiation-induced cell death. In view of a possible combination of Erufosine and radiotherapy in vivo we determined the pharmacokinetics and bioavailability as well as the tolerability of Erufosine in nude mice. NMRI (nu/nu) nude mice were treated by intraperitoneal or subcutaneous injections of 5 to 40 mg/kg body weight Erufosine every 48 h for one to three weeks. Erufosine-concentrations were measured in brain, lungs, liver, small intestine, colon, spleen, kidney, stomach, adipoid tissue, and muscle by tandem-mass spectroscopy. Weight course, blood cell count and clinical chemistry were analyzed to evaluate general toxicity. Intraperitoneal injections were generally well tolerated in all dose groups but led to a transient loss of the bodyweight (<10%) in a dose dependent manner. Subcutaneous injections of high-dose Erufosine caused local reactions at the injection site. Therefore, this regimen at 40 mg/kg body weight Erufosine was stopped after 14 days. No gross changes were observed in organ weight, clinical chemistry and white blood cell count in treated compared to untreated controls except for a moderate increase in lactate dehydrogenase and aspartate-aminotransferase after intensive treatment. Repeated Erufosine injections resulted in drug-accumulation in different organs with maximum concentrations of about 1000 nmol/g in spleen, kidney and lungs. Erufosine was well tolerated and organ-concentrations surpassed the cytotoxic drug concentrations in vitro. Our investigations establish the basis for a future efficacy testing of Erufosine in xenograft tumor models in nude mice alone and in combination with chemo- or radiotherapy

  16. Diclofenac sex-divergent drug-drug interaction with Sunitinib: pharmacokinetics and tissue distribution in male and female mice.

    Science.gov (United States)

    Chew, Chii Chii; Ng, Salby; Chee, Yun Lee; Koo, Teng Wai; Liew, Ming Hui; Chee, Evelyn Li-Ching; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L; Segarra, Ignacio

    2017-08-01

    Coadministration of diclofenac and sunitinib, tyrosine kinase inhibitor, led to sex-divergent pharmacokinetic drug-drug interaction outcomes. Male and female mice were administered 60 mg/kg PO sunitinib alone (control groups) or with 30 mg/kg PO diclofenac. Sunitinib concentration in plasma, brain, kidney and liver were determined by HPLC and non-compartmental pharmacokinetic parameters calculated. In male mice, diclofenac decreased AUC 0→∞ 38% in plasma (p diclofenac increased the liver uptake efficiency in male (27%, p diclofenac with probable clinical translatability due to potential different effects in male and female patients requiring careful selection of the NSAID and advanced TDM to implement a personalized treatment.

  17. Pharmacokinetics and pharmacodynamics of DSTA4637A: A novel THIOMAB™ antibody antibiotic conjugate against Staphylococcus aureus in mice.

    Science.gov (United States)

    Zhou, Chenguang; Lehar, Sophie; Gutierrez, Johnny; Rosenberger, Carrie M; Ljumanovic, Nina; Dinoso, Jason; Koppada, Neelima; Hong, Kyu; Baruch, Amos; Carrasco-Triguero, Montserrat; Saad, Ola; Mariathasan, Sanjeev; Kamath, Amrita V

    DSTA4637A, a novel THIOMAB™ antibody antibiotic conjugate (TAC) against Staphylococcus aureus (S. aureus), is currently being investigated as a potential therapy against S. aureus infections. Structurally, TAC is composed of an anti-S. aureus antibody linked to a potent antibiotic, dmDNA31. The goal of the current study was to characterize the pharmacokinetics (PK) of TAC in mice, assess the effect of S. aureus infection on its PK, and evaluate its pharmacodynamics (PD) by measuring the bacterial load in various organs at different timepoints following TAC treatment. Plasma concentrations of 3 analytes, total antibody (TAb), antibody-conjugated dmDNA31 (ac-dmDNA31), and unconjugated dmDNA31, were measured in these studies. In non-infected mice (target antigen absent), following intravenous (IV) administration of a single dose of TAC, systemic concentration-time profiles of both TAb and ac-dmDNA31 were bi-exponential and characterized by a short distribution phase and a long elimination phase as expected for a monoclonal antibody-based therapeutic. Systemic exposures of both TAb and ac-dmDNA31 were dose proportional over the dose range tested (5 to 50 mg/kg). In a mouse model of systemic S. aureus infection (target antigen present), a single IV dose of TAC demonstrated PK behavior similar to that in the non-infected mice, and substantially reduced bacterial load in the heart, kidney, and bones on 7 and 14 d post dosing. These findings have increased our understanding of the PK and PK/PD of this novel molecule, and have shown that at efficacious dose levels the presence of S. aureus infection had minimal effect on TAC PK.

  18. The pharmacokinetics of Tcsup(99m)-diethyl IDA in hyperferremic mice

    International Nuclear Information System (INIS)

    Sawas-Dimopoulou, C.; Soulpi, C.; Toubanakis, N.

    1985-01-01

    Previously, portal zone fibrosis was observed with deposition of iron in the periportal liver cells and to a lesser extent in the Kupffer cells. Surprisingly, biochemical tests show little disturbance except for a positive BSP test. That would suggest a peculiar sensitivity to iron overload of the important bile excretory pathway including organic anions such as BSP, conjugated bilirubin, dyes and IDA derivatives. The purpose of the present study is to investigate the effect of hyperferremia on the pharmacokinetics of Tcsup(99m)-diethyl IDA. (Auth.)

  19. In vitro metabolism and pharmacokinetic studies on methylone

    DEFF Research Database (Denmark)

    Pedersen, Anders Just; Petersen, Trine Hedebrink; Linnet, Kristian

    2013-01-01

    Abuse of the stimulant designer drug methylone (methylenedioxymethcathinone) has been documented in most parts of the world. As with many of the new designer drugs that continuously appear in the illicit drug market, little is known about the pharmacokinetics of methylone. Using in vitro studies...

  20. Radiosensitizing activity and pharmacokinetics of multiple dose administered KU-2285 in peripheral nerve tissue in mice

    International Nuclear Information System (INIS)

    Iwai, Hiroyuki; Matsuno, Etsuko; Sasai, Keisuke; Abe, Mitsuyuki; Shibamoto, Yuta

    1994-01-01

    In a clinical trial in which a 2-nitroimidazole radiosensitizer was administered repeatedly, the dose-limiting toxicity was found to be peripheral neuropathy. In the present study, the in vivo radiosensitizing activity of KU-2285 in combination with radiation dose fractionation, and the pharmacokinetics of cumulative dosing of KU-2285 in the peripheral nerves were examined. The ability of three nitroimidazoles, misonidazole (MISO), etanidazole (SR-2508) and KU-2285, to sensitize SCCVII tumors to radiation treatment has been compared for drug doses in the range 0-200 mg/kg. Single radiation doses or two different fractionation schedules (6 Gy/fractions x three fractions/48 h or 5 Gy/fractions x five fractions/48 h) were used; the tumor cell survival was determined using an in vivo/in vitro colony assay. The pharmacokinetics in the sciatic nerves were undertaken, when KU-2285 or etanidazole were injected at a dose of 200 mg/kg intravenously one, two, three, or four times at 2-h intervals. At less than 100 mg/kg, KU-2285 sensitized SCCVII tumors more than MISO and SR-2508 by fractionated irradiation. Evaluation of pharmacokinetics in the peripheral nerves showed that the apparent biological half-life of SR-2508 increased with the increases in the number of administrations, whereas that of KU-2285 became shorter. Since most clinical radiotherapy is given in small multiple fractions, KU-2285 appears to be a hypoxic cell radiosensitizer that could be useful in such regimens, and that poses no risk of chronic peripheral neurotoxicity. 12 refs., 5 figs., 1 tab

  1. Pharmacokinetics and modeling of immune cell trafficking: quantifying differential influences of target tissues versus lymphocytes in SJL and lipopolysaccharide-treated mice

    Directory of Open Access Journals (Sweden)

    Banks William A

    2012-10-01

    Full Text Available Abstract Background Immune cell trafficking into the CNS and other tissues plays important roles in health and disease. Rapid quantitative methods are not available that could be used to study many of the dynamic aspects of immune cell-tissue interactions. Methods We used pharmacokinetics and modeling to quantify and characterize the trafficking of radioactively labeled lymphocytes into brain and peripheral tissues. We used variance from two-way ANOVAs with 2 × 2 experimental designs to model the relative influences of lymphocytes and target tissues in trafficking. Results We found that in male CD-1 mice, about 1 in 5,000 intravenously injected lymphocytes entered each gram of brain. Uptake by brain was 2 to 3 times higher in naïve SJL females, but uptake by spleen and clearance from blood was lower, demonstrating a dichotomy in immune cell distribution. Treatment of CD-1 mice with lipopolysaccharide (LPS increased immune cell uptake into brain but decreased uptake by spleen and axillary nodes. Conclusions Differences in brain uptake and in uptake by spleen between SJL and CD-1 mice were primarily determined by lymphocytes, whereas differences in uptake with LPS were primarily determined by lymphocytes for the brain but by the tissues for the spleen and the axillary lymph node. These results show that immune cells normally enter the CNS and that tissues and immune cells interact in ways that can be quantified by pharmacokinetic models.

  2. Dosing-time contributes to chronotoxicity of clofarabine in mice via means other than pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Jia-Jie Luan

    2016-05-01

    Full Text Available To evaluate the time- and dose-dependent toxicity of clofarabine in mice and to further define the chronotherapy strategy of it in leukemia, we compared the mortality rates, LD50s, biochemical parameters, histological changes and organ indexes of mice treated with clofarabine at various doses and time points. Plasma clofarabine levels and pharmacokinetic parameters were monitored continuously for up to 8 hours after the single intravenous administration of 20 mg/kg at 12:00 noon and 12:00 midnight by high performance liquid chromatography (HPLC-UV method. Clofarabine toxicity in all groups fluctuated in accordance with circadian rhythms in vivo. The toxicity of clofarabine in mice in the rest phase was more severe than the active one, indicated by more severe liver damage, immunodepression, higher mortality rate, and lower LD50. No significant pharmacokinetic parameter changes were observed between the night and daytime treatment groups. These findings suggest the dosing-time dependent toxicity of clofarabine synchronizes with the circadian rhythm of mice, which might provide new therapeutic strategies in further clinical application.

  3. Pharmacokinetics of chimeric L6 conjugated to indium-111- and yttrium-90-DOTA-peptide in tumor-bearing mice

    International Nuclear Information System (INIS)

    DeNardo, S.J.; Zhong, G.R.; Salako, Q.

    1995-01-01

    A bifunctional chelating agent, DOTA-Gly 3 -L-(p-isothiocyanato)-phenylalanine amide (DOTA-peptide-NCS), was studied in nude mice bearing human breast cancer xenografts (HBT 3477) to determine its potential for radioimmunoconjugate therapy. Indium-111 and yttrium-90 were attached to an anti-adenocarcinoma chimeric L6 (ChL6) monoclonal antibody (MAb) after pre-chelation to the DOTA-peptide-NCS and the desired neutral radiochelates were obtained by purification. The unique characteristic of the DOTA-peptide-NCS to form neutral complexes with trivalent metals was utilized to separate the resulting 111 In and 90 Y radiochelates from excess chelating agent and other anionic by-products resulting from metal impurities. The purified radiochelates were then conjugated to ChL6. The paramacokinetics of 111 In- and 90 Y-DOTA-peptide-ChL6 were obtained for 5 days after injection in nude mice bearing HBT 3477 xenographs. The results were compared with the pharmacokinetics of 125 I-ChL6 obtained in the same mouse model. The whole-body clearance of 125 I-ChL6, 90 Y-and 111 In-DOTA-peptide-ChL6 was monoexponential with biologic half-times of 92, 104 and 160 hr, respectively. Blood clearances of the three radiopharmaceuticals were biphasic. The radiometal immunoconjugates had greater tumor uptake and slower clearances. Indium-111- and 90 Y-DOTA-peptide-ChL6 can be produced at high specific activity with fewer than one chelate per MAb by using a pre-labeling method that permits radiochelate purification by charge selection. Studies in mouse xenografts indicate that tumor uptake in enhanced and a favorable therapeutic index is achieved using these agents. 29 refs., 7 figs., 2 tabs

  4. In vitro and in vivo studies of pharmacokinetics and antitumor efficacy of D07001-F4, an oral gemcitabine formulation.

    Science.gov (United States)

    Hao, Wei-Hua; Wang, Jong-Jing; Hsueh, Shu-Ping; Hsu, Pei-Jing; Chang, Li-Chien; Hsu, Chang-Shan; Hsu, Kuang-Yang

    2013-02-01

    The chemotherapy agent gemcitabine is currently administered intravenously because the drug has poor oral bioavailability. In order to assess the pharmacokinetics and antitumor activity of D07001-F4, a new self-microemulsifying oral drug delivery system preparation of gemcitabine, this study was performed to compare the effect of D07001-F4 with administered gemcitabine in vitro and in vivo. D07001-F4 pharmacokinetics was examined by evaluation of in vitro deamination of D07001-F4 and gemcitabine hydrochloride by recombinant human cytidine deaminase (rhCDA) and in vivo evaluation of D07001-F4 pharmacokinetics in mice. Antitumor activity was evaluated by comparing the effect of D07001-F4 and gemcitabine hydrochloride in inhibiting growth in nine cancer cell lines and by examining the effect of D07001-F4 and gemcitabine in two xenograft tumor models in mice. In vitro deamination of D07001-F4 by rhCDA was 3.3-fold slower than deamination of gemcitabine hydrochloride. Growth inhibition by D07001-F4 of 7 of the 8 cancer cell lines was increased compared with that seen with gemcitabine hydrochloride, and D07001-F4 inhibited the growth of pancreatic and colon cancer xenografts. In vivo pharmacokinetics showed the oral bioavailability of D07001-F4 to be 34%. D07001-F4 was effective against several cancer types, was metabolized more slowly than gemcitabine hydrochloride, and exhibited enhanced oral bioavailability.

  5. A Three-Pulse Release Tablet for Amoxicillin: Preparation, Pharmacokinetic Study and Physiologically Based Pharmacokinetic Modeling.

    Science.gov (United States)

    Li, Jin; Chai, Hongyu; Li, Yang; Chai, Xuyu; Zhao, Yan; Zhao, Yunfan; Tao, Tao; Xiang, Xiaoqiang

    2016-01-01

    Amoxicillin is a commonly used antibiotic which has a short half-life in human. The frequent administration of amoxicillin is often required to keep the plasma drug level in an effective range. The short dosing interval of amoxicillin could also cause some side effects and drug resistance, and impair its therapeutic efficacy and patients' compliance. Therefore, a three-pulse release tablet of amoxicillin is desired to generate sustained release in vivo, and thus to avoid the above mentioned disadvantages. The pulsatile release tablet consists of three pulsatile components: one immediate-release granule and two delayed release pellets, all containing amoxicillin. The preparation of a pulsatile release tablet of amoxicillin mainly includes wet granulation craft, extrusion/spheronization craft, pellet coating craft, mixing craft, tablet compression craft and film coating craft. Box-Behnken design, Scanning Electron Microscope and in vitro drug release test were used to help the optimization of formulations. A crossover pharmacokinetic study was performed to compare the pharmacokinetic profile of our in-house pulsatile tablet with that of commercial immediate release tablet. The pharmacokinetic profile of this pulse formulation was simulated by physiologically based pharmacokinetic (PBPK) model with the help of Simcyp®. Single factor experiments identify four important factors of the formulation, namely, coating weight of Eudragit L30 D-55 (X1), coating weight of AQOAT AS-HF (X2), the extrusion screen aperture (X3) and compression forces (X4). The interrelations of the four factors were uncovered by a Box-Behnken design to help to determine the optimal formulation. The immediate-release granule, two delayed release pellets, together with other excipients, namely, Avicel PH 102, colloidal silicon dioxide, polyplasdone and magnesium stearate were mixed, and compressed into tablets, which was subsequently coated with Opadry® film to produce pulsatile tablet of

  6. Requirements for pharmacokinetic evaluation of antibiotics in phase I studies.

    Science.gov (United States)

    Bergan, T

    1986-01-01

    Initial pharmacokinetic studies usually include healthy volunteers to minimize variation generated by diseases. Ethical aspects of initial studies are paramount. The guidelines of the Helsinki Declaration should be followed or even extended. Thorough toxicologic screening in animals is a prerequisite. The use of radioisotopes for pharmacokinetic studies should be limited. The basic design of studies includes cross-over administration of intravenous and oral doses of several sizes. Bioavailability, total area under the serum concentration curve, serum half-life, amount eliminated in urine as active drug, and metabolism are the most important data. The fate of the parent compound and of its possible metabolites in both healthy persons and ill individuals (including those with renal or hepatic dysfunction) should be monitored. Diet may have consequences with regard to recommended dosage schedules. When possible, tissue penetration of antibiotics should be assessed, preferably through the analysis of peripheral human lymph and of suction-blister and peritoneal fluids. Theoretical dosage schedules based on pharmacokinetic assessments in healthy persons should be tested in patients with infectious disease, particularly in those with reduced renal and/or hepatic function.

  7. Comparative Pharmacokinetics Study of Icariin and Icariside II in Rats

    Directory of Open Access Journals (Sweden)

    Tao Cheng

    2015-12-01

    Full Text Available To explore the pharmacokinetic properties of icariin (ICA and icariside II (ICA II following intragastric and intravenous administration in rats, a rapid and sensitive method by using ultra-performance liquid chromatography–tandem mass spectroscopy (UPLC-MS/MS was developed and validated for the simultaneous quantification of ICA and ICA II in rat plasma. The quantification was performed by using multiple reaction monitoring of the transitions m/z 677.1/531.1 for ICA, 515.1/369.1 for ICA II and 463.1/301.1 for diosmetin-7-O-β-d-glucopyranoside (IS. The assay showed linearity over the concentration range of 1.03–1032 ng/mL, with correlation coefficients of 0.9983 and 0.9977. Intra- and inter-day precision and accuracy were within 15%. The lower limit of quantification for both ICA and ICA II was 1.03 ng/mL, respectively. The recovery of ICA and ICA II was more than 86.2%. The LC-MS/MS method has been successfully used in the pharmacokinetic studies of ICA and ICA II in rats. The results indicated that 91.2% of ICA was transformed into ICA II after oral administration by rats, whereas only 0.4% of ICA was transformed into ICA II after intravenous administration. A comparison of the pharmacokinetics of ICA and ICA II after oral administration revealed that the Cmax and AUC0–t of ICA II were 3.8 and 13.0 times higher, respectively, than those of ICA. However, after intravenous administration, the Cmax and AUC0–t of ICA II were about only 12.1% and 4.2% of those of ICA. These results suggest that ICA and ICA II have distinct pharmacokinetic properties, and the insights obtained facilitate future pharmacological action studies.

  8. [A study of population pharmacokinetics of linezolid in Chinese].

    Science.gov (United States)

    Zhang, L; Bai, N; Liu, Y N; Wang, R

    2016-12-12

    Objective: To study the population pharmacokinetic (PPK) profiles of linezolid in Chinese healthy volunteers and infected patients. Methods: Linezolid 600 mg was administered to 31 Chinese healthy volunteers with a single dose and to 57 infected patients every 12 h for at least 5 doses. High performance liquid chromatography was applied to determine the plasma concentration of linezolid. Nonlinear mixed-effects modeling method was applied to analyze the PPK profiles. Results: For healthy volunteers with single dose of linezolid, 2-compartment with linear elimination model was the most appropriate structural pharmacokinetic model. The population typical value of apparent volume of central compartment was 26.99 L, volume of peripheral compartment was 22.22 L, apparent clearance of central compartment was 7.99 L/h, and clearance of peripheral compartment was 101.28 L/h. For each 1 kg deviation of weight from the mean value, 0.62 L of volume of peripheral compartment was correlated. For Chinese infected patients with multiple doses of linezolid, 1-compartment with linear elimination model was the most appropriate structural pharmacokinetic model. The population typical value of apparent volume was 38.85 L, and apparent clearance was 4.70 L/h. For each 1 kg deviation of weight from the mean value, 0.79 L of volume, as well as 0.04 L/h of clearance were correlated. For each 1 year deviation of age from the mean value, -0.045 L/h of clearance was correlated. Conclusions: The pharmacokinetic profiles of linezolid in Chinese simulate a 2-compartment with linear elimination model when single dose is administrated, and the weight is linearly positive-correlated to volume. While a 1-compartment with linear elimination model is appropriate when multiple doses are administrated, and the weight is linearly positive-correlated to volume and clearance, but the age is linearly negative-correlated to clearance.

  9. Pharmacokinetic Study of Piracetam in Focal Cerebral Ischemic Rats.

    Science.gov (United States)

    Paliwal, Pankaj; Dash, Debabrata; Krishnamurthy, Sairam

    2018-04-01

    Cerebral ischemia affects hepatic enzymes and brain permeability extensively. Piracetam was investigated up to phase III of clinical trials and there is lack of data on brain penetration in cerebral ischemic condition. Thus, knowledge of the pharmacokinetics and brain penetration of piracetam during ischemic condition would aid to improve pharmacotherapeutics in ischemic stroke. Focal cerebral ischemia was induced by middle cerebral artery occlusion for 2 h in male Wistar rats followed by reperfusion. After 24 h of middle cerebral artery occlusion or 22 h of reperfusion, piracetam was administered for pharmacokinetic, brain penetration, and pharmacological experiments. In pharmacokinetic study, blood samples were collected at different time points after 200-mg/kg (oral) and 75-mg/kg (intravenous) administration of piracetam through right external jugular vein cannulation. In brain penetration study, the cerebrospinal fluid, systemic blood, portal blood, and brain samples were collected at pre-designated time points after 200-mg/kg oral administration of piracetam. In a separate experiment, the pharmacological effect of the single oral dose of piracetam in middle cerebral artery occlusion was assessed at a dose of 200 mg/kg. All the pharmacokinetic parameters of piracetam including area under curve (AUC 0-24 ), maximum plasma concentration (C max ), time to reach the maximum plasma concentration (t max ), elimination half-life (t 1/2 ), volume of distribution (V z ), total body clearance, mean residence time, and bioavailability were found to be similar in ischemic stroke condition except for brain penetration. Piracetam exposure (AUC 0-2 ) in brain and CSF were found to be 2.4- and 3.1-fold higher, respectively, in ischemic stroke compared to control rats. Piracetam significantly reduced infarct volume by 35.77% caused by middle cerebral artery occlusion. There was no change in the pharmacokinetic parameters of piracetam in the ischemic stroke model except for

  10. Blood pharmacokinetics of tertiary amyl methyl ether in male and female F344 rats and CD-1 mice after nose-only inhalation exposure.

    Science.gov (United States)

    Sumner, Susan C J; Janszen, Derek B; Asgharian, Bahman; Moore, Timothy A; Bobbitt, Carol M; Fennell, Timothy R

    2003-01-01

    Interest in understanding the biological behavior of aliphatic ethers has increased owing to their use as gasoline additives. The purpose of this study was to investigate the blood pharmacokinetics of the oxygenate tertiary amyl methyl ether (TAME), its major metabolite tertiary amyl alcohol (TAA) and acetone in rats and mice following inhalation exposure to TAME. Species differences in the area under the curve (AUC) for TAME were significant at each exposure concentration. For rats, the blood TAME AUC increased in proportion with an increase in exposure concentration. For mice, an increase in exposure concentration (100-500 ppm) resulted in a disproportional increase in the TAME AUC. Mice had greater (two- to threefold) blood concentrations of TAA compared with rats following exposure to 2500 or 500 ppm TAME. Mice had a disproportional increase in the TAA AUC with an increase in exposure concentration (100-500 ppm). This difference could result from saturation of a process (e.g. oxidation, glucuronide conjugation) that is involved in the further metabolism of TAA. For each species, gender and exposure concentration, acetone increased during exposure and returned to control values by 16 h following exposure. The source of acetone could be both as a metabolite of TAA or an effect on endogenous metabolism produced by exposure to TAME. Copyright 2003 John Wiley & Sons, Ltd.

  11. Pharmacokinetic Studies on Metoprolol - Eudragit Matrix Tablets ...

    African Journals Online (AJOL)

    HP

    Zero order release of drug was observed from all the tablets. ... Conclusion: It can be concluded from this single-dose study that the reference and test ... effect [2]. The mean time to reach maximum plasma concentration and mean elimination.

  12. [Study on differences between pharmacokinetics and chromatopharmacodynamics for Chinese materia medica formulae].

    Science.gov (United States)

    He, Fuyuan; Deng, Kaiwen; Zou, Huan; Qiu, Yun; Chen, Feng; Zhou, Honghao

    2011-01-01

    To study on the differences between chromatopharmacokinetics (pharmacokinetics with fingerprint chromatography) and chromatopharmacodynamics (pharmacodynamics with fingerprint chromatography) of Chinese materia medica formulae to answer the question whether the pharmacokinetic parameters of multiple composites can be utilized to guide the medication of multiple composites. On the base of established four chromatopharmacology (pharmacology with chromatographic fingerprint), the pharmacokinetics, and pharmacodynamics were analyzed comparably on their mathematical model and parameter definition. On the basis of quantitative pharmacology, the function expressions and total statistical parameters, such as total zero moment, total first moment, total second moment of the pharmacokinetics, and pharmacodynamics were analyzed to the common expressions and elucidated results for single and multiple components in Chinese materia medica formulae. Total quantitative pharmacokinetic, i.e., chromatopharmacokinetic parameter were decided by each component pharmacokinetic parameters, whereas the total quantitative pharmacodynamic, i.e., chromatopharmacodynamic parameter were decided by both of pharmacokinetic and pharmacodynamic parameters of each components. The pharmacokinetic parameters were corresponded to pharmacodynamic parameters with an existing stable effective coefficient when the constitutive ratio of each composite was a constant. The effects of Chinese materia medica were all controlled by pharmacokinetic and pharmacodynamic coefficient. It is a special case that the pharmacokinetic parameter could independently guide the clinical medication for single component whereas the chromatopharmacokinetic parameters are not applied to the multiple drug combination system, and not be used to solve problems of chromatopharmacokinetic of Chinese materia medica formulae.

  13. pethidine study Epidural and intramuscular a pharmacokinetic

    African Journals Online (AJOL)

    1983-02-05

    Feb 5, 1983 ... study would indicate to what extent absorption and transport via the blood influenced the actions of epidural pethidine. Department of ... gas chromatograph using a 1,1 metre glass column of 2% Car- bowax 20M + 3% KOH on ...

  14. Pharmacokinetics of Acetaminophen in Hind Limbs Unloaded Mice: A Model System Simulating the Effects of Low Gravity on Astronauts in Space

    Science.gov (United States)

    Peterson, Amanda; Risin, Semyon A.; Ramesh, Govindarajan T.; Dasgupta, Amitava; Risin, Diana

    2008-01-01

    The pharmacokinetics (PK) of medications administered to astronauts could be altered by the conditions in Space. Low gravity and free floating (and associated hemodynamic changes) could affect the absorption, distribution, metabolism and excretion of the drugs. Knowledge of these alterations is essential for adjusting the dosage and the regimen of drug administration in astronauts. Acquiring of such knowledge has inherent difficulties due to limited opportunities for experimenting in Space. One of the approaches is to use model systems that simulate some of the Space conditions on Earth. In this study we used hind limbs unloaded mice (HLU) to investigate the possible changes in PK of acetaminophen, a widely used analgesic with high probability of use by astronauts. The HLU is recognized as an appropriate model for simulating the effects of low gravity on hemodynamic parameters. Mice were tail suspended (n = 24) for 24-96 hours prior to introduction of acetaminophen (150 - 300 mg/kg). The drug (in aqueous solution containing 10% ethyl alcohol by volume) was given orally by a gavage procedure and after the administration of acetaminophen mice were additionally suspended for 30 min, 1 and 2 hours. Control mice (n = 24) received the same dose of acetaminophen and were kept freely all the time. Blood specimens were obtained either from retroorbital venous sinuses or from heart. Acetaminophen concentration was measured in plasma by the fluorescent polarization immunoassay and the AxSYM analyzer (Abbott Laboratories). In control mice peak acetaminophen concentration was achieved at 30 min. By 1 hour the concentration decreased to less than 50% of the peak level and at 2 hours the drug was almost undetectable in the serum. HLU for 24 hours significantly altered the acetaminophen pharmacokinetic: at 30 min the acetaminophen concentrations were significantly (both statistically and medically significant) lower than in control mice. The concentrations also reduced less

  15. Development of a mechanism-based pharmacokinetic/pharmacodynamic model to characterize the thermoregulatory effects of serotonergic drugs in mice

    Directory of Open Access Journals (Sweden)

    Xi-Ling Jiang

    2016-09-01

    Full Text Available We have shown recently that concurrent harmaline, a monoamine oxidase-A inhibitor (MAOI, potentiates serotonin (5-HT receptor agonist 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT-induced hyperthermia. The objective of this study was to develop an integrated pharmacokinetic/pharmacodynamic (PK/PD model to characterize and predict the thermoregulatory effects of such serotonergic drugs in mice. Physiological thermoregulation was described by a mechanism-based indirect-response model with adaptive feedback control. Harmaline-induced hypothermia and 5-MeO-DMT–elicited hyperthermia were attributable to the loss of heat through the activation of 5-HT1A receptor and thermogenesis via the stimulation of 5-HT2A receptor, respectively. Thus serotonergic 5-MeO-DMT–induced hyperthermia was readily distinguished from handling/injection stress-provoked hyperthermic effects. This PK/PD model was able to simultaneously describe all experimental data including the impact of drug-metabolizing enzyme status on 5-MeO-DMT and harmaline PK properties, and drug- and stress-induced simple hypo/hyperthermic and complex biphasic effects. Furthermore, the modeling results revealed a 4-fold decrease of apparent SC50 value (1.88–0.496 µmol/L for 5-MeO-DMT when harmaline was co-administered, providing a quantitative assessment for the impact of concurrent MAOI harmaline on 5-MeO-DMT–induced hyperthermia. In addition, the hyperpyrexia caused by toxic dose combinations of harmaline and 5-MeO-DMT were linked to the increased systemic exposure to harmaline rather than 5-MeO-DMT, although the body temperature profiles were mispredicted by the model. The results indicate that current PK/PD model may be used as a new conceptual framework to define the impact of serotonergic agents and stress factors on thermoregulation.

  16. Biotransformation of a novel antimitotic agent, I-387, by mouse, rat, dog, monkey, and human liver microsomes and in vivo pharmacokinetics in mice.

    Science.gov (United States)

    Ahn, Sunjoo; Kearbey, Jeffrey D; Li, Chien-Ming; Duke, Charles B; Miller, Duane D; Dalton, James T

    2011-04-01

    3-(1H-Indol-2-yl)phenyl)(3,4,5-trimethoxyphenyl)methanone (I-387) is a novel indole compound with antitubulin action and potent antitumor activity in various preclinical models. I-387 avoids drug resistance mediated by P-glycoprotein and showed less neurotoxicity than vinca alkaloids during in vivo studies. We examined the pharmacokinetics and metabolism of I-387 in mice as a component of our preclinical development of this compound and continued interest in structure-activity relationships for antitubulin agents. After a 1 mg/kg intravenous dose, noncompartmental pharmacokinetic analysis in plasma showed that clearance (CL), volume of distribution at steady state (Vd(ss)), and terminal half-life (t(1/2)) of I-387 were 27 ml per min/kg, 5.3 l/kg, and 7 h, respectively. In the in vitro metabolic stability study, half-lives of I-387 were between 10 and 54 min by mouse, rat, dog, monkey, and human liver microsomes in the presence of NADPH, demonstrating interspecies variability. I-387 was most stable in rat liver microsomes and degraded quickly in monkey liver microsomes. Liquid chromatography-tandem mass spectrometry was used to identify phase I metabolites. Hydroxylation, reduction of a ketone group, and O-demethylation were the major metabolites formed by the liver microsomes of the five species. The carbonyl group of I-387 was reduced and identified as the most labile site in human liver microsomes. The results of these drug metabolism and pharmacokinetic studies provide the foundation for future structural modification of this pharmacophore to improve stability of drugs with potent anticancer effects in cancer patients.

  17. [Pharmacokinetic studies of flomoxef in the neonatal field].

    Science.gov (United States)

    Kimura, K; Miyano, T; Shimomura, H

    1991-11-01

    Flomoxef (FMOX), a new broad spectrum oxacephem antibiotic, was studied in the neonatal field and the pharmacokinetic results obtained are summarized below. 1. Serum concentrations of FMOX after dosages of 20 mg/kg via 1 hour drip infusion were 21.8 +/- 7.59 micrograms/ml, 15.4 +/- 4.35 micrograms/ml, 4.3 +/- 2.88 micrograms/ml at 1, 2 and 5 hours after administration, respectively, and T 2/1 (beta)'s averaged 2.08 +/- 1.01 hours. 2. Urinary excretion rates were 53.38 +/- 16.94% in the first 7 hours after administration.

  18. Efficacy, pharmacokinetics, tisssue distribution, and metabolism of the Myc-Max disruptor, 10058-F4 [Z,E]-5-[4-ethylbenzylidine]-2-thioxothiazolidin-4-one, in mice.

    Science.gov (United States)

    Guo, Jianxia; Parise, Robert A; Joseph, Erin; Egorin, Merrill J; Lazo, John S; Prochownik, Edward V; Eiseman, Julie L

    2009-03-01

    c-Myc is commonly activated in many human tumors and is functionally important in cellular proliferation, differentiation, apoptosis and cell cycle progression. The activity of c-Myc requires noncovalent interaction with its client protein Max. In vitro studies indicate the thioxothiazolidinone, 10058-F4, inhibits c-Myc/Max dimerization. In this study, we report the efficacy, pharmacokinetics and metabolism of this novel protein-protein disruptor in mice. SCID mice bearing DU145 or PC-3 human prostate cancer xenografts were treated with either 20 or 30 mg/kg 10058-F4 on a qdx5 schedule for 2 weeks for efficacy studies. For pharmacokinetics and metabolism studies, mice bearing PC-3 or DU145 xenografts were treated with 20 mg/kg of 10058-F4 i.v. Plasma and tissues were collected 5-1440 min after dosing. The concentration of 10058-F4 in plasma and tissues was determined by HPLC, and metabolites were characterized by LC-MS/MS. Following a single iv dose, peak plasma 10058-F4 concentrations of approximately 300 muM were seen at 5 min and declined to below the detection limit at 360 min. Plasma concentration versus time data were best approximated by a two-compartment, open, linear model. The highest tissue concentrations of 10058-F4 were found in fat, lung, liver, and kidney. Peak tumor concentrations of 10058-F4 were at least tenfold lower than peak plasma concentrations. Eight metabolites of 10058-F4 were identified in plasma, liver, and kidney. The terminal half-life of 10058-F4 was approximately 1 h, and the volume of distribution was >200 ml/kg. No significant inhibition of tumor growth was seen after i.v. treatment of mice with either 20 or 30 mg/kg 10058-F4. The lack of significant antitumor activity of 10058-F4 in tumor-bearing mice may have resulted from its rapid metabolism and low concentration in tumors.

  19. A pharmacokinetic study of diclofenac sodium in rats.

    Science.gov (United States)

    Yuan, Jing; Ma, He; Cen, Nannan; Zhou, Ai; Tao, Hengxun

    2017-08-01

    The aim of the present study was to examine the pharmacokinetics of a single intravenous injection (i.v.) and oral administration (p.o.) of diclofenac sodium (DIC) in Sprague-Dawley (SD) rats. Twelve male SD rats were divided into 2 groups (n=6 per group); one group was injected intravenously with 2 mg/kg DIC, whereas the other group was lavaged with 2 mg/kg DIC. Blood samples were collected prior to DIC delivery (0 h) and 0.033, 0.083, 0.167, 0.25, 0.5, 1, 2, 4, 6, and 8 h post-administration. Blood plasma samples were analyzed using liquid chromatography-mass spectrometry (LC-MS/MS) following pretreatment to induce protein precipitation. Pharmacokinetics software was applied to calculate relevant pharmacokinetic parameters using a non-compartmental model. Following i.v. administration of DIC, the terminal elimination rate constant (λ z ), apparent terminal elimination half-life (t ½ ), area under the concentration-time curve from time 0 extrapolated to infinity (AUC0 -∞ ), clearance (CL), apparent volume of distribution (V z ), mean residence time (MRT), and apparent volume of distribution at steady state (V ss ) were 0.57±0.05 l/h, 1.22±0.11 h, 3356±238 h × ng/ml, 0.60±0.04 l/h, 1.05±0.10 l, 1.05±0.07 h and 0.63±0.07 l, respectively. Following p.o. administration of DIC, the λ z , t ½ , C max , t max , AUC 0-∞ , CL, V z , MRT were: 0.63±0.12 l/h, 1.12±0.18 h, 1272±112 ng/ml, 0.19±0.04 h, 2501±303 h × ng/ml, 0.81±0.10 l/h, 1.29±0.12 l, and 2.70±0.18 h, respectively. The pharmacokinetic parameters of i.v. and p.o. DIC in rats show that the drug is rapidly absorbed, distributed, and eliminated.

  20. Plasma Pharmacokinetic and Heart Distribution Studies of Z-GP-EPI ...

    African Journals Online (AJOL)

    22, 44 µmol/kg) by intravenous injection and 70 mice (30 ... anticancer agents at the tumor site, where drug- converting ... at a temperature of 25 ± 2 °C and a relative humidity of 75 ± 5 ..... Jones G. Pharmacokinetics of vitamin D toxicity. Am J.

  1. Pharmacokinetic study of mycophenolic acid in Iranian kidney transplant patients

    Directory of Open Access Journals (Sweden)

    Saeed Rezaee

    2013-02-01

    Full Text Available Background: The purpose of this study was to characterize the pharmacokinetic parameters of mycophenolic acid (MPA in Iranian kidney transplant patients. Methods: Plasma MPA concentration of mycophenolate mofetile (MMF 1 gram two times a day was measured in 21 Iranian kidney transplant recipients receiving treatment. Patients who entered the study had been transplanted for more than 3 months and their drug level was supposed to be at steady state. MMF concentration was measured with high-performance liquid chromatography (HPLC. Results: The plasma MPA concentration-time curve was characterized by an early sharp peak at about 1 hour postdose. The mean Area Under Curve (AUC, Cmax and Tmax were 47.0±18.3 µg.h/ml, 18.6±8.5 µg/ml and 1.0±0.5 hours respectively. Conclusion: The plasma MPA concentration-time curve pattern of Iranian patients was similar and consistent with previously reported profiles in other populations taking the same dose. Keywords: Mycophenolate mofetil, Mycophenolic acid, Pharmacokinetics, Area Under Curve, Kidney transplantation

  2. Pharmacokinetics of 99m Tc-EDDA/HYNIC-Lys-D-Phe-RGD in athymic mice with induced malignant tumors for integrin imaging

    International Nuclear Information System (INIS)

    Lopez D, F.A.; Pedraza L, M.; Murphy, C.A. de; Ferro F, G.; Hernandez H, E.

    2007-01-01

    Full text: Nuclear medicine imaging techniques are non-invasive and monitor the spatiotemporal distribution of molecular events. Radiolabeled RGD-peptides are currently investigated to target integrin receptors for in vivo tumor imaging. The α v β 3 integrin is a target structure involved in the angio genesis process which mediates the binding to extracellular matrix via different proteins such as vitronectin, fibronectin and von Willebrand factor. The aim of this research was to prepare [ 99m Tc]-Lys-D-Phe-RGD and to evaluate its pharmacokinetics in athymic mice with three different induced malignant tumors. Tumor uptake values of 99m Tc-Lys-D-Phe-RGD labeled via HYNIC and EDDA showed good ability to target α v β 3 integrin receptors in the three different kinds of tumors (breast, prostate and neuroendocrine). A high in vivo stability and favorable pharmacokinetic properties such as fast blood clearance, rapid renal excretion, low liver and muscle uptake and low intestinal excretion were observed. This study demonstrated that 99m Tc-EDDA/HYNIC-Lys-D-Phe-RGD is a specific and potential radiopharmaceutical to image α v β 3 integrin receptors in a variety of tumors. (Author)

  3. [Pharmacokinetic and clinical studies of flomoxef in the perinatal period].

    Science.gov (United States)

    Matsuda, S; Hirayama, H; Oh, K; Tamate, K; Sengoku, K; Ishikawa, M; Shimizu, T; Haga, H; Hasegawa, T; Takada, H

    1993-07-01

    Pharmacokinetic and clinical studies on flomoxef (FMOX) in the perinatal period were carried out and following results were obtained 1. The pharmacokinetic parameter T1/2's of FMOX in maternal serum, umbilical cord serum and amniotic fluid in mothers after single intravenous injection of 1 g (n = 46) and 2 g (n = 34) were 1.11, 9.24, 9.24 hours and 2.54, 12.49, 12.49 hours, respectively. Cmax's and Tmax's of umbilical cord serum and amniotic fluid were 12.71, 11.77 micrograms/ml and 0.57, 3.35 hours upon single dose of 1 g i.v., and 35.17, 12.37 micrograms/ml and 0.32, 3.42 hours upon single dose of 2 g i.v., respectively. 2. Clinical usefulness were evaluated in 93 cases including were various infections in pregnancy and puerperal period. In pregnancy cases, clinical efficacy rate was 95.5% (21/22), and 100% in puerperal period. Bacteriological response rate was 84.6% (eradicated: 29, decreased: 4, unchanged: 2, replaced: 4 and unknown: 8 cases). No severe side effects nor clinical laboratory test results were observed in any cases. From above basic and clinical results, we conclude that FMOX is a useful and safe agent for various infections in pregnancy and puerperal period.

  4. Anti-cancer, pharmacokinetic and biodistribution studies of cremophor el free alternative paclitaxel formulation.

    Science.gov (United States)

    Jain, Subheet K; Utreja, Puneet; Tiwary, Ashok K; Mahajan, Mohit; Kumar, Nikhil; Roy, Partha

    2014-01-01

    The aim of the present investigation is to determine the in vivo potential of previously developed and optimized Cremophor EL free paclitaxel (CF-PTX) formulation consisting of soya phosphatidylcholine and biosurfactant sodium deoxycholate. CF-PTX was found to have drug loading of 6 mg/ml similar to Cremophor EL based marketed paclitaxel formulation. In the present study, intracellular uptake, repeated dose 28 days sub-acute toxicity, anti-cancer activity, biodistribution and pharmacokinetic studies were conducted to determine in vivo performance of CF-PTX formulation in comparison to marketed paclitaxel formulation. Intracellular uptake of CF-PTX was studied using A549 cells by fluorescence activated cell sorting assay (FACS) and fluorescence microscopy. In vivo anti-cancer activity of CF-PTX was evaluated using Ehrlich ascites carcinoma (EAC) model in mice followed by biodistribution and pharmacokinetic studies. FACS investigation showed that fluorescence marker acridine orange (AO) solution showed only 19.8±1.1% intracellular uptake where as significantly higher uptake was observed in the case of AO loaded CF-PTX formulation (85.4±2.3%). The percentage reduction in tumor volume for CF-PTX (72.5±2.3%) in EAC bearing mice was found to be significantly (p<0.05) higher than marketed formulation (58.6±2.8%) on 14th day of treatment. Pharmacokinetic and biodistribution studies showed sustained plasma concentration of paclitaxel depicted by higher mean residence time (MRT; 18.2±1.8 h) and elimination half life (12.8±0.6 h) with CF-PTX formulation as compared to marketed formulation which showed 4.4±0.2 h MRT and 3.6±0.4 h half life. The results of the present study demonstrated better in vivo performance of CF-PTX and this formulation appears to be a promising carrier for sustained and targeted delivery of paclitaxel.

  5. Assessment of chimeric mice with humanized livers in new drug development: generation of pharmacokinetics, metabolism and toxicity data for selecting the final candidate compound.

    Science.gov (United States)

    Kamimura, Hidetaka; Ito, Satoshi

    2016-01-01

    1. Chimeric mice with humanized livers are expected to be a novel tool for new drug development. This review discusses four applications where these animals can be used efficiently to collect supportive data for selecting the best compound in the final stage of drug discovery. 2. The first application is selection of the final compound based on estimated pharmacokinetic parameters in humans. Since chimeric mouse livers are highly repopulated with human hepatocytes, hepatic clearance values in vivo could be used preferentially to estimate pharmacokinetic profiles for humans. 3. The second is prediction of human-specific or disproportionate metabolites. Chimeric mice reproduce human-specific metabolites of drugs under development to conform to ICH guidance M3(R2), except for compounds that were extensively eliminated by co-existing mouse hepatocytes. 4. The third is identifying metabolites with distinct pharmacokinetic profiles in humans. Slow metabolite elimination specifically in humans increases its exposure level, but if its elimination is faster in laboratory animals, the animal exposure level might not satisfy ICH guidance M3(R2). 5. Finally, two examples of reproducing acute liver toxicity in chimeric mice are introduced. Integrated pharmacokinetics, metabolism and toxicity information are expected to assist pharmaceutical scientists in selecting the best candidate compound in new drug development.

  6. Pharmacokinetic study of medicinal polymers: models based on dextrans

    International Nuclear Information System (INIS)

    Kulakov, V.N.; Pimenova, G.N.; Matveev, V.A.; Sedov, V.V.; Vasil'ev, A.E.

    1986-01-01

    The authors study the pharmacokinetics of dextrans with various molecular masses modified by fluorescein isothiocyanate (FITC) using a radioisotope method. The radionuclide 125 I was selectively bound to a FITC residue attached to the polysaccharide by electrochemical iodination under potentiostatic conditions. In the experiments, dextrans modified by FITC were labeled with 125 I (DF- 125 I) by electrochemical iodination. The separation of DF- 125 I and FITC from ionic forms of the radionuclide not bound to the polymer was carried out. The properties of the samples obtained are presented. The radioactivity accumulated in the rate organs and urine studied are shown. The features of DF- 125 I behavior in the blood and liver are examined

  7. A Comparative Study of the Pharmacokinetics of Conventional and ...

    African Journals Online (AJOL)

    Erah

    Purpose: To examine the pharmacokinetics of a formulated aceclofenac sustained release ... over 24 h and analyzed by high performance liquid chromatography (HPLC). .... The response factor .... slower drug disposition and prolonged effect.

  8. Pharmacokinetic Study of Bioactive Flavonoids in the Traditional Japanese Medicine Keigairengyoto Exerting Antibacterial Effects against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Takashi Matsumoto

    2018-01-01

    Full Text Available Recent studies have demonstrated that flavonoid glucuronides can be deconjugated to the active form aglycone by β-glucuronidase-expressing macrophages. Keigairengyoto (KRT is a flavonoid-rich traditional Japanese medicine reported to enhance bacterial clearance through immune modulation. Our aims are to examine the pharmacokinetics of KRT flavonoids and to identify active flavonoids contributing to the adjuvant effects of KRT. KRT was evaluated at pharmacokinetic analysis to quantify absorbed flavonoids, and cutaneous infection assay induced in mice by inoculation of Staphylococcus aureus. Preventive or therapeutic KRT administration reduced the number of bacteria in the infection site as well as macroscopic and microscopic lesion scores with efficacies similar to antibiotics. Pharmacokinetic study revealed low plasma levels of flavonoid aglycones after KRT administration; however, plasma concentrations were enhanced markedly by β-glucuronidase treatment, with baicalein the most abundant (Cmax, 1.32 µg/mL. In random screening assays, flavonoids such as bacalein, genistein, and apigenin enhanced bacteria phagocytosis by macrophages. Glucuronide bacalin was converted to aglycone baicalein by incubation with living macrophages, macrophage lysate, or skin homogenate. Taken together, the adjuvant effect of KRT may be due to some blood-absorbed flavonoids which enhance macrophage functions in host defense. Flavonoid-rich KRT may be a beneficial treatment for infectious skin inflammation.

  9. Normal viability and altered pharmacokinetics in mice lacking mdr1-type (drug-transporting) P-glycoproteins

    NARCIS (Netherlands)

    Schinkel, A. H.; Mayer, U.; Wagenaar, E.; Mol, C. A.; van Deemter, L.; Smit, J. J.; van der Valk, M. A.; Voordouw, A. C.; Spits, H.; van Tellingen, O.; Zijlmans, J. M.; Fibbe, W. E.; Borst, P.

    1997-01-01

    The mdr1-type P-glycoproteins (P-gps) confer multidrug resistance to cancer cells by active extrusion of a wide range of drugs from the cell. To study their physiological roles, we have generated mice genetically deficient in the mdr1b gene [mdr1b (-/-) mice] and in both the mdr1a and mdr1b genes

  10. Pharmacokinetic study with computational tools in the medicinal chemistry course

    Directory of Open Access Journals (Sweden)

    Monique Araújo de Brito

    2011-12-01

    Full Text Available To improve the teaching-learning process in the Medicinal Chemistry course, new strategies have been incorporated into practical classes of this fundamental discipline of the pharmaceutical curriculum. Many changes and improvements have been made in the area of medicinal chemistry so far, and students should be prepared for these new approaches with the use of technological resources in this field. Practical activities using computational techniques have been directed to the evaluation of chemical and physicochemical properties that affect the pharmacokinetics of drugs. Their objectives were to allow students to know these tools, to learn how to access them, to search for the structures of drugs and to analyze results. To the best of our knowledge, this is the first study in Brazil to demonstrate the use of computational practices in teaching pharmacokinetics. Practical classes using Osiris and Molinspiration were attractive to students, who developed the activities easily and acquired better theoretical knowledge.Para melhorar o processo ensino-aprendizagem no curso de Química Medicinal novas estratégias estão sendo incorporadas às aulas práticas desta disciplina fundamental do currículo farmacêutico. Muitas mudanças e melhorias vêm marcando a área de química medicinal e por isso é importante que os alunos sejam colocados nestas novas abordagens na área, com a utilização de recursos tecnológicos. As atividades práticas foram direcionadas para a avaliação dos dados químicos e físico-químicos de fármacos que influenciam as propriedades farmacocinéticas com o auxílio de técnicas computacionais. Os objetivos foram permitir aos alunos conhecer essas ferramentas, saber como acessá-las, procurar as estruturas de fármacos e analisar os resultados. Este é o primeiro estudo publicado no Brasil que apresenta aula prática computacional sobre o tema farmacocinética. As aulas práticas utilizando os servidores Osiris e

  11. [Microbiological and pharmacokinetic studies on flomoxef in ophthalmologic field].

    Science.gov (United States)

    Ooishi, M; Sakaue, F; Oomomo, A; Tazawa, H

    1989-05-01

    Microbiological and pharmacokinetic studies were carried out on flomoxef (FMOX, 6315-S), a new oxacephem parenteral antibiotic, in the ophthalmologic field. The results obtained are summarized as follows. FMOX has a broad antimicrobial activity spectrum against Gram-positive and Gram-negative bacteria. The MIC distribution against Staphylococcus aureus isolated from clinical cases was less than or equal to 0.20 - greater than or equal to 100 micrograms/ml with the peak value of 0.39 micrograms/ml. Concentrations of FMOX in aqueous humor and ocular tissues were determined after intravenous injection of 50 mg/kg to rabbits. FMOX showed a peak level of 2.2 micrograms/ml in the aqueous humor at 1/2 hour after administration with the ratio to serum level of 3.4%. Levels of FMOX in external and internal ocular tissues were 12.7 - 76.5 micrograms/g, less than 0.8 - 34.4 micrograms/g (ml) at 1/2 hour after administration, respectively. From these results, we concluded that FMOX may be expected to be a useful and valuable agent against infections in the ophthalmologic field.

  12. Phytosomal curcumin: A review of pharmacokinetic, experimental and clinical studies.

    Science.gov (United States)

    Mirzaei, Hamed; Shakeri, Abolfazl; Rashidi, Bahman; Jalili, Amin; Banikazemi, Zarrin; Sahebkar, Amirhossein

    2017-01-01

    Curcumin, a hydrophobic polyphenol, is the principal constituent extracted from dried rhizomes of Curcuma longa L. (turmeric). Curcumin is known as a strong anti-oxidant and anti-inflammatory agent that has different pharmacological effects. In addition, several studies have demonstrated that curcumin is safe even at dosages as high as 8g per day; however, instability at physiological pH, low solubility in water and rapid metabolism results in a low oral bioavailability of curcumin. The phytosomal formulation of curcumin (a complex of curcumin with phosphatidylcholine) has been shown to improve curcumin bioavailability. Existence of phospholipids in phytosomes leads to specific physicochemical properties such as amphiphilic nature that allows dispersion in both hydrophilic and lipophilic media. The efficacy and safety of curcumin phytosomes have been shown against several human diseases including cancer, osteoarthritis, diabetic microangiopathy and retinopathy, and inflammatory diseases. This review focuses on the pharmacokinetics as well as pharmacological and clinical effects of phytosomal curcumin. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  13. The pharmacokinetics of xylazine hydrochloride: an interspecific study.

    Science.gov (United States)

    Garcia-Villar, R; Toutain, P L; Alvinerie, M; Ruckebusch, Y

    1981-06-01

    The pharmacokinetic disposition of xylazine hydrochloride is described after both intravenous and intramuscular injection of a single dose, in four domestic species: horse, cattle, sheep and dog, by an original high performance liquid chromatographic technique. Remarkably small interspecific differences are reported. After intravenous administration, systemic half-life (t1/2 beta) ranged between 22 min (sheep) and 50 min (horse) while the distribution phase is transient with half-life (t1/2 alpha) ranging from 1.2 min (cattle) to 5.9 min (horse). The peak level of drug concentration in the plasma is reached after 12-14 min in all the species studied following intramuscular administration. Xylazine bioavailability, as measured by the ratios of the areas under the intravenous and intramuscular plasma concentration versus time curves, ranged from 52% to 90% in dog, 17% to 73% in sheep and 40% to 48% in horse. The low dosage in cattle did not permit calculation. Kinetic data are correlated with clinical data and the origins of interspecific differences are discussed.

  14. Anesthetic constituents of Zanthoxylum bungeanum Maxim.: A pharmacokinetic study.

    Science.gov (United States)

    Rong, Rong; Cui, Mei-Yu; Zhang, Qi-Li; Zhang, Mei-Yan; Yu, Yu-Ming; Zhou, Xian-Ying; Yu, Zhi-Guo; Zhao, Yun-Li

    2016-07-01

    A sensitive and selective ultra high performance liquid chromatography with tandem mass spectrometry method was established and validated for the simultaneous determination of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool in rat plasma after the subcutaneous and intravenous administration of an extract of the pericarp of Zanthoxylum bungeanum Maxim. Piperine was used as the internal standard. The analytes were extracted from rat plasma by liquid-liquid extraction with ethyl acetate and separated on a Thermo Hypersil GOLD C18 column (2.1 mm × 50 mm, 1.9 μm) with a gradient elution system at a flow rate of 0.4 mL/min. The mobile phase consisted of acetonitrile/0.05% formic acid in water and the total analysis time was 4 min. Positive electrospray ionization was performed using multiple reaction monitoring mode for the analytes. The calibration curves of the three analytes were linear over the tested concentration range. The intra- and interday precision was no more than 13.6%. Extraction recovery, matrix effect, and stability were satisfactory in rat plasma. The developed and validated method was suitable for the quantification of hydroxy-α-sanshool, hydroxy-β-sanshool, and hydroxy-γ-sanshool and successfully applied to a pharmacokinetic study of these analytes after subcutaneous and intravenous administration to rats. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Bacterial β-glucuronidase inhibition protects mice against enteropathy induced by indomethacin, ketoprofen or diclofenac: mode of action and pharmacokinetics.

    Science.gov (United States)

    Saitta, Kyle S; Zhang, Carmen; Lee, Kang Kwang; Fujimoto, Kazunori; Redinbo, Matthew R; Boelsterli, Urs A

    2014-01-01

    1.  We have previously demonstrated that a small molecule inhibitor of bacterial β-glucuronidase (Inh-1; [1-((6,8-dimethyl-2-oxo-1,2-dihydroquinolin-3-yl)-3-(4-ethoxyphenyl)-1-(2-hydroxyethyl)thiourea]) protected mice against diclofenac (DCF)-induced enteropathy. Here we report that Inh-1 was equally protective against small intestinal injury induced by other carboxylic acid-containing non-steroidal anti-inflammatory drugs (NSAIDs), indomethacin (10 mg/kg, ip) and ketoprofen (100 mg/kg, ip). 2.  Inh-1 provided complete protection if given prior to DCF (60 mg/kg, ip), and partial protection if administered 3-h post-DCF, suggesting that the temporal window of mucosal protection can be extended for drugs undergoing extensive enterohepatic circulation. 3.  Pharmacokinetic analysis of Inh-1 revealed an absolute bioavailability (F) of 21% and a short t1/2 of <1 h. This low F was shown to be due to hepatic first-pass metabolism, as confirmed with the pan-CYP inhibitor, 1-aminobenzotriazole. 4.  Using the fluorescent probe 5 (and 6)-carboxy-2',7'-dichlorofluorescein, we demonstrated that Inh-1 did not interfere with hepatobiliary export of glucuronides in gall bladder-cannulated mice. 5.  These data are compatible with the hypothesis that pharmacological inhibition of bacterial β-glucuronidase-mediated cleavage of NSAID glucuronides in the small intestinal lumen can protect against NSAID-induced enteropathy caused by locally high concentrations of NSAID aglycones.

  16. Biodistribution and pharmacokinetics of dapivirine-loaded nanoparticles after vaginal delivery in mice.

    Science.gov (United States)

    das Neves, José; Araújo, Francisca; Andrade, Fernanda; Amiji, Mansoor; Bahia, Maria Fernanda; Sarmento, Bruno

    2014-07-01

    To assess the potential of polymeric nanoparticles (NPs) to affect the genital distribution and local and systemic pharmacokinetics (PK) of the anti-HIV microbicide drug candidate dapivirine after vaginal delivery. Dapivirine-loaded, poly(ethylene oxide)-coated poly(epsilon-caprolactone) (PEO-PCL) NPs were prepared by a nanoprecipitation method. Genital distribution of NPs and their ability to modify the PK of dapivirine up to 24 h was assessed after vaginal instillation in a female mouse model. Also, the safety of NPs upon daily administration for 14 days was assessed by histological analysis and chemokine/cytokine content in vaginal lavages. PEO-PCL NPs (180-200 nm) were rapidly eliminated after administration but able to distribute throughout the vagina and lower uterus, and capable of tackling mucus and penetrate the epithelial lining. Nanocarriers modified the PK of dapivirine, with higher drug levels being recovered from vaginal lavages and vaginal/lower uterine tissues as compared to a drug suspension. Systemic drug exposure was reduced when NPs were used. Also, NPs were shown safe upon administration for 14 days. Dapivirine-loaded PEO-PCL NPs were able to provide likely favorable genital drug levels, thus attesting the potential value of using this vaginal drug delivery nanosystem in the context of HIV prophylaxis.

  17. Study of GABA in healthy volunteers: pharmacokinetics and pharmacodynamics

    Directory of Open Access Journals (Sweden)

    Junfeng eLi

    2015-11-01

    Full Text Available Preclinical studies show that GABA exerts anti-diabetic effects in rodent models of type 1 diabetes. Because little is known about its absorption and effects in humans, we investigated the pharmacokinetics and pharmacodynamics of GABA in healthy volunteers. Twelve subjects were subjected to an open-labeled, three-period trial involving sequential oral administration of placebo, 2g GABA once, and 2g GABA three times/day for seven days, with a 7-day washout between each period. GABA was rapidly absorbed (Tmax: 0.5~1 h with the half-life (t1/2 of 5 h. No accumulation was observed after repeated oral GABA administration for 7 days. Remarkably, GABA significantly increased circulating insulin levels in the subjects under either fasting (1.6-fold, single dose; 2.0-fold, repeated dose; p<0.01 or fed conditions (1.4-fold, single dose; 1.6-fold, repeated dose; p<0.01. GABA also increased glucagon levels only under fasting conditions (1.3-fold, single dose, p<0.05; 1.5-fold, repeated dose, p<0.01. However, there were no significant differences in the insulin-to-glucagon ratio and no significant change in glucose levels in these healthy subjects during the study period. Importantly, GABA significantly decreased glycated albumin levels in the repeated dosing period. Subjects with repeated dosing showed an elevated incidence of minor adverse events in comparison to placebo or the single dosing period, most notably transitional discomforts such as dizziness and sore throat. However, there were no serious adverse events observed throughout the study. Our data show that GABA is rapidly absorbed and tolerated in human beings; its endocrine effects, exemplified by increasing islet hormonal secretion, suggest potential therapeutic benefits for diabetes.

  18. Pharmacokinetic study of gallocatechin-7-gallate from Pithecellobium clypearia Benth. in rats

    Directory of Open Access Journals (Sweden)

    Chao Li

    2016-01-01

    Full Text Available The pharmacokinetic profile of gallocatechin-7-gallate (J10688 was studied in rats after intravenous administration. Male and female Sprague-Dawley (SD rats received 1, 3, and 10 mg/kg (i.v. of J10688 and plasma drug concentrations were determined by a high performance liquid chromatography-mass spectrometry (LC–MS method. The pharmacokinetic software Data Analysis System (Version 3.0 was used to calculate the pharmacokinetic parameters. For different i.v. doses of J10688, the mean peak plasma concentration (C0 values ranged from 11.26 to 50.82 mg/L, and mean area under the concentration-time curve (AUC0–t values ranged from 1.75 to 11.80 (mg·h/L. J10688 lacked dose-dependent pharmacokinetic properties within doses between 1 and 10 mg/kg, based on the power model. The method developed in this study was sensitive, precise, and stable. The pharmacokinetic properties of J10688 in SD rats were shown to have rapid distribution and clearance values. These pharmacokinetic results may contribute to an improved understanding of the pharmacological actions of J10688.

  19. Pharmacokinetic and bioequivalence study of itopride HCl in healthy volunteers.

    Science.gov (United States)

    Cho, Kyung-Jin; Cho, Wonkyung; Cha, Kwang-Ho; Park, Junsung; Kim, Min-Soo; Kim, Jeong-Soo; Hwang, Sung-Joo

    2010-01-01

    In the present study two different formulations containing 50 mg itopride HCl (N-[4-12-(dimethylamino)ethoxylbenzyl]-3,4-dimethoxybenzamide HCl, CAS 122898-67-3) were compared in 28 healthy male volunteers in order to compare the bioavailability and prove the bioequivalence. The study was performed in an open, single dose randomized, 2-sequence, crossover design in 28 healthy male volunteers with a one-week washout period. Blood samples for pharmacokinetic profiling were drawn at selected times during 24 h. The serum concentrations of itopride HCl were determined using a specific and sensitive HPLC method with fluorescence detection. The detection limit of itopride HCl was 5 ng/ml and no endogenous compounds were found to interfere with analysis. The mean AUC(0-4h), AUC(0 --> infinity), C(max), T(max) and T1/2 were 865.28 ng x h/ml, 873.04 ng x h/ml, 303.72 ng/ml, 0.75 h, and 2.95 h, respectively, for the test formulations, and 833.00 ng x h/ml, 830.97 ng x h/ml, 268.01 ng/ml, 0.78 h, and 2.83 h, respectively, for the reference formulation. Both primary target parameters AUC(0 --> infinity) and C(max) were log-transformed and tested parametrically by analysis of variance (ANOVA). 90% confidence intervals of AUC(0 --> infinity) and C(max) were 100.57%-109.56% and 105.46%-121.18%, respectively, and were in the range of acceptable limits of bioequivalence (80-125%). Based on these results, the two formulations of itopride HCl are considered to be bioequivalent.

  20. Development of a Mass Spectrometric Method for Pharmacokinetic Study of Trastuzumab

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Nam Young; Choi, Jin Nyoung; Kang, Jeong Won; Choi, Do Young; Kim, Kwang Pyo [Kyung Hee Univ., Yongin (Korea, Republic of); Park, Gyutae [CKD Research Institute, Yongin (Korea, Republic of)

    2014-06-15

    The HPLC-MS/MS method described here is a simple, rapid and specific method for determining the concentration of biologics in mouse serum. This method was validated for the quantification trastuzumab in ICR mice serum. Although the ELISA method is available for the pharmacokinetics study for trastuzumab, but these methods require development of the target specific antibodies. Generally, the development of the target specific antibodies for quantification is time consuming and expensive. In contrast, MRM-based method does not need antibodies for quantification. The therapeutic monoclonal antibody drug Trastuzumab (INN; trade name Herceptin) is widely used for treating metastatic breast cancer patients with overexpression of HER2 on the tumor. Trastuzumab is a representative target therapeutics as a monoclonal antibody that selectively binds with high affinity to the extracellular domain of the human epidermal growth factor receptor 2 protein, HER2. HER2 is amplified or over-expressed in about 20% to 30% of patients with breast cancer and is associated with aggressive disease. Trastuzumab has an inhibitory effect on the overexpression of HER2 receptor, thereby it has been used in treating breast cancer, and also gastric cancer.

  1. Effects of MicroRNA-34a on the Pharmacokinetics of Cytochrome P450 Probe Drugs in Mice.

    Science.gov (United States)

    Jilek, Joseph L; Tian, Ye; Yu, Ai-Ming

    2017-05-01

    MicroRNAs (miRNAs or miRs), including miR-34a, have been shown to regulate nuclear receptor, drug-metabolizing enzyme, and transporter gene expression in various cell model systems. However, to what degree miRNAs affect pharmacokinetics (PK) at the systemic level remains unknown. In addition, miR-34a replacement therapy represents a new cancer treatment strategy, although it is unknown whether miR-34a therapeutic agents could elicit any drug-drug interactions. To address this question, we refined a practical single-mouse PK approach and investigated the effects of a bioengineered miR-34a agent on the PK of several cytochrome P450 probe drugs (midazolam, dextromethorphan, phenacetin, diclofenac, and chlorzoxazone) administered as a cocktail. This approach involves manual serial blood microsampling from a single mouse and requires a sensitive liquid chromatography-tandem mass spectrometry assay, which was able to illustrate the sharp changes in midazolam PK by ketoconazole and pregnenolone 16 α -carbonitrile as well as phenacetin PK by α -naphthoflavone and 3-methylcholanthrene. Surprisingly, 3-methylcholanthrene also decreased systemic exposure to midazolam, whereas both pregnenolone 16 α -carbonitrile and 3-methylcholanthrene largely reduced the exposure to dextromethorphan, diclofenac, and chlorzoxazone. Finally, the biologic miR-34a agent had no significant effects on the PK of cocktail drugs but caused a marginal (45%-48%) increase in systemic exposure to midazolam, phenacetin, and dextromethorphan in mice. In vitro validation of these data suggested that miR-34a slightly attenuated intrinsic clearance of dextromethorphan. These findings from single-mouse PK and corresponding mouse liver microsome models suggest that miR-34a might have minor or no effects on the PK of coadministered cytochrome P450-metabolized drugs. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  2. Patient acceptability and practical implications of pharmacokinetic studies in patients with advanced cancer.

    Science.gov (United States)

    Dobbs, N A; Twelves, C J; Ramirez, A J; Towlson, K E; Gregory, W M; Richards, M A

    1993-01-01

    We have studied the practical implications and acceptability to patients of pharmacokinetic studies in 34 women receiving anthracyclines for advanced breast cancer. The following parameters were recorded: age, ECOG performance status, psychological state (Rotterdam Symptom Checklist), cytotoxic drug and dose, number of venepunctures for treatment and sampling, and time when the sampling cannula was removed. Immediately after finishing pharmacokinetic sampling, patients completed a questionnaire which revealed that (i) all patients understood sampling was for research, (ii) 35% of patients experienced problems with sampling, (iii) benefits from participation were perceived by 56% of patients. Of 20 patients later questioned after completion of their treatment course, 40% recalled difficulties with blood sampling. Factors identifying in advance those patients who tolerate pharmacokinetic studies poorly were not identified but the number of venepunctures should be minimised. Patients may also perceive benefits from 'non-therapeutic' research.

  3. A comprehensive review of recent studies on pharmacokinetics of traditional Chinese medicines (2014-2017) and perspectives.

    Science.gov (United States)

    Shi, Peiying; Lin, Xinhua; Yao, Hong

    2018-05-01

    Traditional Chinese medicines (TCMs) have a long history for safely treating human diseases. Unlike western medicine, TCMs usually contain multiple components synergistically and holistically acting on the diseases. It remains a big challenge to represent rationally the in vivo process of multiple components of TCMs for understanding the relationship between administration and therapeutic effects. For years, efforts were always made to face the challenge, and the achievements were obvious. Here, we give an comprehensive overview of the recent investigation progress (from 2015 to 2017, except the part of 'integrated pharmacokinetics of TCMs' from 2014 to 2017 and the part of 'reverse pharmacokinetics in drug discovery from natural medicines' in 2014) on pharmacokinetics of TCMs, mainly referring to the following six aspects: (1) classical pharmacokinetic studies on TCMs; (2) absorbed components and metabolites identification of TCMs; (3) pharmacokinetic herb-drug interactions and herb-herb interactions with TCMs; (4) integrated pharmacokinetics of TCMs; (5) pharmacokinetic and pharmacodynamic combination studies to dissect the action mechanisms of TCMs; and (6) reverse pharmacokinetics in drug discovery from natural medicines. Finally, based on the insights from the recent progress and our latest efforts, we propose new perspectives on the integrated pharmacokinetics of TCMs.

  4. Pharmacokinetic parameters of ethylnitrosourea, methylnitrosourea and dimethylnitrosamine determined since their clastogenic activity in mice

    International Nuclear Information System (INIS)

    Morales R, P.; Vallarino K, T.

    1997-01-01

    The latent period (PL) and the effective activity time (TAE) of ethylnitrosourea (ENU), dimethylnitrosamine (DMN) and methylnitrosourea (MNU) were determined through comparison of production kinetics at micronucleus polychromatic erythrocytes in peripheric blood of mice caused by these agents, with that one produced by gamma radiation. Starting from the fact that acute exposure to ionizing radiation causes damage in the genetic material immediately, therefore PL and TAE in this case are practically zero. The obtained results show that PL for 25 or 50 mg ENU/kg is 3.6 and 1.6 h respectively, although the differences among them were not significant. These data show that ENU reaches marrow relatively fast. TAE for the same doses was 5.3 h and 17 h. This shows that mutagen is not depurated very quickly and while doses is greater time is longer in that mutagen can performs. The induction curve of EPC-MN by DMN (8 mg/kg) showed two peaks, what suggests that can be involucred two metabolites, two MN induction mechanisms or two leisure types. The fact that the second peak were not presented in all the animals and that the time of appearance were not regular, it suggests an effect maybe metabolic that is associated to the high toxicity of DMN. PL and TAE calculated in the first peak were of 9.7 h and - 2.2 h being statistically significant only PL. The fact that its PL was too greater it is in according with its requirement of bioactivation in the liver. On the other hand what TAE were too low its shows that DMN is eliminated fastly by the organism. The MNU at 4 and 8 mg/kg doses has a PL over 15 h, which is very large for a direct mutagen and a TAE very short since even its duration is lesser than in the radiation case, this shows that MNU reacts quickly, or what its metabolic degradation velocity and/or excretion are very fast. (Author)

  5. [Pharmacokinetic study of six aconitine alkaloids in aconiti lateralis radix praeparata in beagle dogs].

    Science.gov (United States)

    Xiao, Ri-Ping; Lai, Xiao-Ping; Zhao, Yai; Yu, Liang-Wen; Zhu, Yue-Lan; Li, Geng

    2014-02-01

    To study the pharmacokinetics characteristics of six Aconitum alkaloids aconitine (AC), mesaconitine (MA), hypaconitine (HA), benzoylaconine (BAC), benzoylmesaconine (BMA) and benzoylhypaconine (BHA) in beagle dogs. An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for simultaneous quantitation of six Aconitum alkaloids in beagle dog plasma after oral administration of Aconiti Lateralis Radix Praeparata decoction. UPLC/MS/MS system coupled with an electrospray ionization (ESI) source was performed in multiple-reaction monitoring (MRM) mode. Sample preparation was performed with solid-phase extraction(SPE) on a 3 mL HLB cartridge before the analysis. The separation was applied on a Waters C8 column (100 mm x 2.1 mm, 1.7 microm) and a gradient elution of methanol and 0.2% formic acid-water was used as mobile phase. The pharmacokinetic parameters were calculated by the results of the analysis through the DAS 2. 1 software (Drug and Statistics for Windows). The results showed that the fitting model for the six Aconitum alkaloids was the one-compartment model pharmacokinetics. The method is successfully used for the pharmacokinetic evaluation of the six Aconitum alkaloids in beagle dog plasma, it can help monitor the ADME/Tox process when taking Aconiti Lateralis Radix Praeparata by observing the pharmacokinetic process. The results provide a good reference for clinical treatment and safe application of Aconiti Lateralis Radix Praeparata.

  6. Pharmacokinetic equivalence study of two formulations of the anticonvulsant pregabalin

    Directory of Open Access Journals (Sweden)

    Tjandrawinata RR

    2015-04-01

    Full Text Available Raymond R Tjandrawinata,1 Effi Setiawati,2 Ratih Sofia Ika Putri,2 Vincent Angga Gunawan,2 Fenny Ong,1 Liana W Susanto,1 Dwi Nofiarny11Dexa Laboratories of Biomolecular Sciences, Cikarang, West Java, Indonesia; 2PT Equilab International Bioavailability and Bioequivalence Laboratory, Jakarta, IndonesiaPurpose: The present study was conducted to evaluate whether the bioavailability of pregabalin capsules 150 mg manufactured by PT Dexa Medica was equivalent to the reference formulation.Methods: This was a randomized, open-label, two-period, two-sequence, and crossover study under fasting condition, with a 1-week washout period. Plasma concentrations of pregabalin from 20 subjects were determined by using a validated liquid chromatography with tandem mass spectrometry (LC-MS/MS detection method. Pharmacokinetic parameters assessed in this study were: area under the plasma concentration–time curve from time zero to last observed quantifiable concentration (AUC0–t, area under the plasma concentration–time curve from time zero to infinity (AUC0–∞, maximum plasma concentration (Cmax, time to maximum plasma concentration (tmax, and terminal half-life (t1/2. The 90% confidence intervals (CIs for the geometric mean ratios of test formulation/reference formulation were calculated for the AUC and Cmax parameters; while tmax difference was analyzed nonparametrically on the original data using the Wilcoxon matched-pairs test, and t1/2 difference was analyzed using Student's paired t-test.Results: The mean (standard deviation [SD] AUC0–t, AUC0–∞, Cmax, and t1/2 of pregabalin from the test formulation were 27,845.86 (4,508.27 ng·h/mL, 28,311.70 (4,790.55 ng·h/mL, 3,999.71 (801.52 ng/mL, and 5.66 (1.20 hours, respectively; while the mean (SD AUC0–t, AUC0–∞, Cmax, and t1/2 of pregabalin from the reference formulation were 27,398.12 (4,266.28 ng·h/mL, 27,904.24 (4,507.31 ng·h/mL, 3,849.50 (814.50 ng/mL, and 5.87 (1.25 hours, respectively

  7. In vivo pharmacokinetic study comparing different methodologies for labelling of Annexin V; Estudo farmacocinetico in vivo comparativo de diferentes metodologias de marcacao da Anexina V

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Josefina da Silva; Pujatti, Priscilla Brunelli; Couto, Renata Martinussi; Araujo, Elaine Bortoleti de Araujo, E-mail: jssantos@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Radiofarmacia

    2008-07-01

    In this work we preliminary results of the evaluation of the influence of the chelating in the pharmacokinetics of ANXA5 radiolabeled with technetium-99m in Swiss mice and using HYNIC and EC as bifunctional chelators are showed.

  8. Pharmacokinetic equivalence study of nonsteroidal anti-inflammatory drug etoricoxib

    Directory of Open Access Journals (Sweden)

    Tjandrawinata RR

    2018-04-01

    Full Text Available Raymond R Tjandrawinata,1 Arini Setiawati,2 Dwi Nofiarny,1 Liana W Susanto,1 Effi Setiawati3 1Dexa Laboratories of Biomolecular Sciences Unit, Dexa Medica Group, Cikarang, West Java, Indonesia; 2Department of Pharmacology and Therapeutics, Medical Faculty, University of Indonesia, Jakarta, Indonesia; 3Bioavailability and Bioequivalence Laboratory Unit, PT Equilab International, Jakarta, Indonesia Purpose: The current study aimed to evaluate whether a generic product of etoricoxib 120 mg film-coated tablet (the test drug was bioequivalent to the reference product (Arcoxia® film-coated tablet 120 mg.Methods: This was a randomized, open-label, two-sequence, crossover study under fasting condition, with a 14-day washout period, involving 26 healthy adult male and female subjects. Blood samples were taken and analyzed for plasma concentrations of etoricoxib (Chemical Abstracts Service [CAS] 202409-33-4 using a high-pressure liquid chromatography–ultraviolet detector (HPLC-UV system capable of measuring etoricoxib concentrations ranging from 5.00 to 5002.90 ng/mL, with the lowest limit of quantitation of 5.00 ng/mL. A noncompartmental method was used to determine the pharmacokinetic parameters of a single-dose administration of the drug, including the area under plasma concentration–time curve from time zero to the time of last observed concentration (AUC0-t, the area under plasma concentration–time curve from time zero to infinity (AUC0-∞, the maximum plasma concentration (Cmax, the time to reach the maximum plasma concentration (tmax, and the terminal half-life (t½.Results: After a single-dose administration of etoricoxib 120 mg film-coated tablet, the mean (SD values for the AUC0-72h and Cmax of the test drug were 45913.42 (13142.19 ng·h/mL and 3155.93 (752.81 ng/mL, respectively; the values for the reference drug were 44577.20 (13541.85 ng⋅h/mL and 2915.13 (772.81 ng/mL, respectively. The geometric mean ratios (90% CIs of the test

  9. A Pharmacokinetic/Pharmacodynamic Study of the Glucocorticoid Receptor Antagonist Mifepristone Combined with Enzalutamide in Castrate Resistant Prostate Cancer

    Science.gov (United States)

    2015-12-01

    AWARD NUMBER: W81XWH-14-1-0021 TITLE: A Pharmacokinetic/Pharmacodynamic Study of the Glucocorticoid Receptor Antagonist Mifepristone Combined...4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER A Pharmacokinetic/Pharmacodynamic Study of the Glucocorticoid Receptor Antagonist Mifepristone Combined...way it adapts is by upregulating another hormone receptor, the glucocorticoid receptor (GR), which may compensate for diminished AR activity. The

  10. Once-daily dosing of saquinavir and low-dose ritonavir in HIV-1-infected individuals: a pharmacokinetic pilot study

    NARCIS (Netherlands)

    van Heeswijk, R. P.; Veldkamp, A. I.; Mulder, J. W.; Meenhorst, P. L.; Lange, J. M.; Beijnen, J. H.; Hoetelmans, R. M.

    2000-01-01

    To investigate the steady-state pharmacokinetics of a once-daily dosing regimen of saquinavir soft gelatin capsules in combination with a low dose of ritonavir in HIV-1-infected individuals. Open-label, multi-dose, pharmacokinetic pilot study. Seven HIV-1-infected individuals who were treated with

  11. Meta-Analysis of Clinical Studies Supports the Pharmacokinetic Variability Hypothesis for Acquired Drug Resistance and Failure of Antituberculosis Therapy

    OpenAIRE

    Pasipanodya, Jotam G.; Srivastava, Shashikant; Gumbo, Tawanda

    2012-01-01

    Laboratory studies have questioned nonadherence as a cause of antituberculosis drug failure and propose that between-patient pharmacokinetic variability may be the cause. This meta-analysis provides clinical evidence that pharmacokinetic variability of isoniazid alone leads to worse microbiological failure, relapse, and acquired drug resistance.

  12. 78 FR 73199 - Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs...

    Science.gov (United States)

    2013-12-05

    ... exposure measures is suitable for documenting BE (e.g., transdermal delivery systems and certain rectal and... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2013-D-1464] Draft Guidance for Industry on Bioequivalence Studies With Pharmacokinetic Endpoints for Drugs Submitted...

  13. Treatment with subcutaneous and transdermal fentanyl: results from a population pharmacokinetic study in cancer patients

    NARCIS (Netherlands)

    Oosten, A.W.; Abrantes, J.A.; Jonsson, S.; Bruijn, P. de; Kuip, E.J.M.; Falcao, A.; Rijt, C.C. van der; Mathijssen, R.H.

    2016-01-01

    PURPOSE: Transdermal fentanyl is effective for the treatment of moderate to severe cancer-related pain but is unsuitable for fast titration. In this setting, continuous subcutaneous fentanyl may be used. As data on the pharmacokinetics of continuous subcutaneous fentanyl are lacking, we studied the

  14. Therapeutic drug monitoring to individualize the dosing of pazopanib: a pharmacokinetic feasibility study

    NARCIS (Netherlands)

    Wit, D. de; Erp, N. van; Hartigh, J. den; Wolterbeek, R..; Hollander-van Deursen, M. den; Labots, M.; Guchelaar (LUMC), H.J.; Verheul, H.M.; Gelderblom, H.

    2015-01-01

    BACKGROUND: Patients treated with the standard dose of pazopanib show a large interpatient variability in drug exposure defined as the area under the plasma concentration-time curve (AUC0-24h). The primary objective of this study was to evaluate the feasibility of pharmacokinetics (PK)-guided

  15. Therapeutic drug monitoring for the individualization of docetaxel dosing: a randomized pharmacokinetic study

    NARCIS (Netherlands)

    Engels, Frederike K.; Loos, Walter J.; van der Bol, Jessica M.; de Bruijn, Peter; Mathijssen, Ron H. J.; Verweij, Jaap; Mathot, Ron A. A.

    2011-01-01

    Docetaxel pharmacokinetic (PK) parameters, notably clearance and exposure (AUC), are characterized by large interindividual variability. The purpose of this study was to evaluate the effect of PK-guided [area under the plasma concentration versus time curve (AUC) targeted], individualized docetaxel

  16. Pharmacokinetically guided sunitinib dosing: a feasibility study in patients with advanced solid tumours

    NARCIS (Netherlands)

    Lankheet, N.; Kloth, J.S.; Gadellaa-van Hooijdonk, C.G.M.; Cirkel, G.A.; Mathijssen, R.H.; Lolkema, M.P.; Schellens, J.H.; Voest, E.E.; Sleijfer, S.; Jonge, M.J. de; Haanen, J.B.; Beijnen, J.H.; Huitema, A.D.; Steeghs, N.

    2014-01-01

    Background:Plasma exposure of sunitinib shows large inter-individual variation. Therefore, a pharmacokinetic (PK) study was performed to determine safety and feasibility of sunitinib dosing based on PK levels.Methods:Patients were treated with sunitinib 37.5 mg once daily. At days 15 and 29 of

  17. Pharmacokinetic bioequivalence studies of a fixed-dose combination of tamsulosin and dutasteride in healthy volunteers.

    Science.gov (United States)

    Fossler, Michael J; Collins, David A; Thompson, Meg M; Nino, Antonio; Bianco, Joseph J; Chetty, Dushen

    2014-05-01

    The combination of dutasteride and tamsulosin may be more effective for the treatment of symptomatic benign prostatic hyperplasia than either treatment alone. We report the results of three pharmacokinetics and tolerability studies, which used a dutasteride/tamsulosin HCl (0.5 mg/0.2 mg) fixed-dose combination (FDC) capsules containing a small dutasteride soft gelatin capsule (smaller than commercial Avodart™) and modified-release tamsulosin pellets that have different amounts of enteric coating. These studies compared the test products to commercial Avodart™ (dutasteride 0.5 mg) and two different commercial tamsulosin HCl 0.2 mg products, Harnal™ Capsules or Harnal-D™ Tablets, which are reportedly bioequivalent to each other. All three studies were randomized single-dose studies in healthy male adults. Study 1 [N = 86 (NCT01254071)] was a two-period crossover study of a dutasteride/tamsulosin HCl FDC versus coadministered Avodart™ and Harnal-D™ Tablets. The pharmacokinetics of both dutasteride and tamsulosin were studied. Study 2 [N = 27 (NCT01471678)] was a four-period crossover study of dutasteride/tamsulosin HCl FDC formulations versus Avodart™ and Harnal™ Capsules or Harnal-D™ Tablets. Only the pharmacokinetics of tamsulosin were studied. Study 3 [N = 40 (NCT01495026)] was a two-period study of dutasteride/tamsulosin HCl FDC formulations versus coadministered Avodart™ and Harnal-D™ Tablets. In this study, only the pharmacokinetics of tamsulosin were studied. Study 2 assessed fed-state pharmacokinetics. Studies 1 and 3 assessed fed- and fasted-state pharmacokinetics. All dutasteride/tamsulosin HCl FDC formulations and coadministered treatments were well-tolerated. In Study 1, the FDC dutasteride was bioequivalent to Avodart™ coadministered with tamsulosin under fed and fasted conditions. In Study 1, the FDC tamsulosin had a slower release than commercial Harnal-D™ Tablets coadministered with dutasteride (fed and fasted

  18. Pharmacokinetics and Safety of Amenamevir in Healthy Subjects: Analysis of Four Randomized Phase 1 Studies.

    Science.gov (United States)

    Kusawake, Tomohiro; Keirns, James J; Kowalski, Donna; den Adel, Martin; Groenendaal-van de Meent, Dorien; Takada, Akitsugu; Ohtsu, Yoshiaki; Katashima, Masataka

    2017-12-01

    Amenamevir (ASP2151) is a nonnucleoside antiherpesvirus compound available for the treatment of varicella-zoster virus infections. In this article we summarize the findings of four phase 1 studies in healthy participants. Four randomized phase 1 studies investigated the safety and pharmacokinetics of single and multiple doses of amenamevir, including the assessment of age group effect (nonelderly vs elderly), food effect, and the relative bioavailability of two formulations. Amenamevir was administered orally at various doses as a single dose (5-2400 mg) or daily (300 or 600 mg/day) for 7 days. Following single and multiple oral doses, amenamevir demonstrated a less than dose proportional increase in the pharmacokinetic parameters area under the plasma drug concentration versus time curve from time zero to infinity (AUC inf ) and C max . After single and multiple oral 300-mg doses of amenamevir, no apparent differences in pharmacokinetics were observed between nonelderly and elderly participants. In contrast, with the amenamevir 600-mg dose both the area under the plasma drug concentration versus time curve from time zero to 24 h and C max were slightly increased and renal clearance was decreased in elderly participants. The pharmacokinetics of amenamevir was affected by food, with AUC inf increased by about 90%. In the bioavailability study, AUC inf and C max were slightly lower following tablet versus capsule administration (decreased by 14 and 12%, respectively), with relative bioavailability of 86%. The different amenamevir doses and formulations were safe and well tolerated; no deaths or serious adverse events were reported. Amenamevir had less than dose proportional pharmacokinetic characteristics. Age may have an influence on amenamevir pharmacokinetics; however, the effect was considered minimal. The pharmacokinetics of amenamevir were affected by food, with AUC inf almost doubling when amenamevir was administered with food. The concentration versus

  19. A clinical pharmacokinetic microdosing study of docetaxel with Japanese patients with cancer.

    Science.gov (United States)

    Fujita, Ken-ichi; Yoshino, Etsuko; Kawara, Kaori; Maeda, Kazuya; Kusuhara, Hiroyuki; Sugiyama, Yuichi; Yokoyama, Taro; Kaneta, Toshikado; Ishida, Hiroo; Sasaki, Yasutsuna

    2015-10-01

    Whether microdosing studies can be used to evaluate the human pharmacokinetics of new anticancer drugs remains unclear. The disposition of docetaxel in cancer patients is linear in terms of dose proportionality. We examined whether the pharmacokinetics of docetaxel in a clinically relevant therapeutic dose could be predicted from the pharmacokinetics of a microdose of docetaxel in Japanese patients with cancer. A microdose of docetaxel (100 μg/patient) was given by 5-min intravenous infusion on day 1, followed by a therapeutic dose of docetaxel (60-75 mg m(-2)), given by 1-h intravenous infusion on day 8. Plasma docetaxel was analyzed by liquid chromatography-tandem mass spectrometry. A two-compartment pharmacokinetic model was used to calculate the area under the plasma concentration-time curve from time 0 to infinity (AUC0-inf). Nine patients received both a microdose and therapeutic dose of docetaxel. The AUC0-inf after microdosing was 3640 ± 1150 ng h L(-1), while that after therapeutic dosing adjusted to 100 mg/patient was 2230 ± 757 µg h L(-1). The ratio of docetaxel clearance in therapeutic dose to that in microdose was 1.8 (P = 0.0041). Plasma α1-acid glycoprotein concentrations negatively correlated with docetaxel clearance at therapeutic dose, whereas the trend was weak at microdose. Docetaxel clearance showed marginal nonlinearity between microdose and therapeutic dose, presumably because of saturation of plasma protein binding; however, the magnitude was within twofold, allowing practically acceptable extrapolation.

  20. Pharmacokinetics and pharmacodynamics study of rhein treating renal fibrosis based on metabonomics approach.

    Science.gov (United States)

    Sun, Hao; Luo, Guangwen; Xiang, Zheng; Cai, Xiaojun; Chen, Dahui

    2016-12-01

    The selection of effect indicators in the pharmacokinetic/ pharmacodynamic study of complex diseases to describe the relationship between plasma concentration and effect indicators is difficult. Three effect indicators of renal fibrosis were successfully determined. The relationship between pharmacokinetics and pharmacodynamics of rhein in rhubarb was elucidated. The study was a metabolomics analysis of rat plasma and pharmacokinetics/ pharmacodynamics of rhein. A sensitive and simple ultra performance liquid chromatography-tandem triple quadrupole mass spectrometry (UPLC-MS/MS) method was applied to determine the rhein plasma concentration in the rat model of renal fibrosis and rat sham-operated group after the administration of rhubarb decoction. Then, the ultra performance liquid chromatography-Micromass quadrupole-time of flight mass spectrometry (UPLC-QTOF/MS) metabolomics method was used to screen biomarkers of renal fibrosis in rat plasma. Furthermore, the relationship between the plasma concentration of rhein and the concentration of three biomarkers directly related to renal fibrosis were analyzed. The three screened biomarkers could represent the effect of rhein treatment on renal fibrosis. Increasing the plasma concentration of rhein tended to restore the concentration of the three biomarkers in the model group compared with that in the sham-operated group. Evident differences in the area under the plasma concentration-time curve (AUC) of rhein were also observed under different pathological states. The results provide valuable information for the clinical application of rhubarb. Rhein intervention could recover the physiological balance in living organisms from the pharmacokinetic/pharmacodynamic levels. New information on the pharmacokinetic/pharmacodynamic study of complex diseases is provided. Copyright © 2016 Elsevier GmbH. All rights reserved.

  1. Prediction of clinical response based on pharmacokinetic/pharmacodynamic models of 5-hydroxytryptamine reuptake inhibitors in mice

    DEFF Research Database (Denmark)

    Kreilgaard, Mads; Smith, D. G.; Brennum, L. T.

    2008-01-01

    Bridging the gap between preclinical research and clinical trials is vital for drug development. Predicting clinically relevant steady-state drug concentrations (Css) in serum from preclinical animal models may facilitate this transition. Here we used a pharmacokinetic/pharmacodynamic (PK...

  2. CLINICAL-PHARMACOLOGY OF ROCURONIUM (ORG-9426) - STUDY OF THE TIME-COURSE OF ACTION, DOSE REQUIREMENT, REVERSIBILITY, AND PHARMACOKINETICS

    NARCIS (Netherlands)

    VANDENBROEK, L; WIERDA, JMKH; SMEULERS, NJ; VANSANTEN, GJ; LECLERCQ, MGL; HENNIS, PJ

    1994-01-01

    Study Objective: To evaluate the time course of action, dose requirement, reversibility, and pharmacokinetics of rocuronium (Org 9426) under 3 anesthetic techniques (nitrous oxide-fentanyl supplemented with propofol halothane, or isoflurane). Design: Prospective, randomized study. Setting: Operating

  3. Semi-Mechanistic Population Pharmacokinetic Modeling of L-Histidine Disposition and Brain Uptake in Wildtype and Pht1 Null Mice.

    Science.gov (United States)

    Wang, Xiao-Xing; Li, Yang-Bing; Feng, Meihua R; Smith, David E

    2018-01-05

    To develop a semi-mechanistic population pharmacokinetic (PK) model to quantitate the disposition kinetics of L-histidine, a peptide-histidine transporter 1 (PHT1) substrate, in the plasma, cerebrospinal fluid and brain parenchyma of wildtype (WT) and Pht1 knockout (KO) mice. L-[ 14 C]Hisidine (L-His) was administrated to WT and KO mice via tail vein injection, after which plasma, cerebrospinal fluid (CSF) and brain parenchyma samples were collected. A PK model was developed using non-linear mixed effects modeling (NONMEM). The disposition of L-His between the plasma, brain, and CSF was described by a combination of PHT1-mediated uptake, CSF bulk flow and first-order micro-rate constants. The PK profile of L-His was best described by a four-compartment model. A more rapid uptake of L-His in brain parenchyma was observed in WT mice due to PHT1-mediated uptake, a process characterized by a Michaelis-Menten component (V max  = 0.051 nmoL/min and K m  = 34.94 μM). A semi-mechanistic population PK model was successfully developed, for the first time, to quantitatively characterize the disposition kinetics of L-His in brain under in vivo conditions. This model may prove a useful tool in predicting the uptake of L-His, and possibly other PHT1 peptide/mimetic substrates, for drug delivery to the brain.

  4. Improved physiologically based pharmacokinetic model for oral exposures to chromium in mice, rats, and humans to address temporal variation and sensitive populations.

    Science.gov (United States)

    Kirman, C R; Suh, M; Proctor, D M; Hays, S M

    2017-06-15

    A physiologically based pharmacokinetic (PBPK) model for hexavalent chromium [Cr(VI)] in mice, rats, and humans developed previously (Kirman et al., 2012, 2013), was updated to reflect an improved understanding of the toxicokinetics of the gastrointestinal tract following oral exposures. Improvements were made to: (1) the reduction model, which describes the pH-dependent reduction of Cr(VI) to Cr(III) in the gastrointestinal tract under both fasted and fed states; (2) drinking water pattern simulations, to better describe dosimetry in rodents under the conditions of the NTP cancer bioassay; and (3) parameterize the model to characterize potentially sensitive human populations. Important species differences, sources of non-linear toxicokinetics, and human variation are identified and discussed within the context of human health risk assessment. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  5. Determination of Acyclovir in Human Plasma Samples by HPLC Method with UV Detection: Application to Single-Dose Pharmacokinetic Study

    Directory of Open Access Journals (Sweden)

    Dragica Zendelovska

    2015-03-01

    CONCLUSION: Good precision, accuracy, simplicity, sensitivity and shorter time of analysis of the method makes it particularly useful for processing of multiple samples in a limited period of time for pharmacokinetic study of acyclovir.

  6. Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies (Final Report)

    Science.gov (United States)

    EPA announced the availability of the final report, Uncertainty and Variability in Physiologically-Based Pharmacokinetic (PBPK) Models: Key Issues and Case Studies. This report summarizes some of the recent progress in characterizing uncertainty and variability in physi...

  7. Atorvastatin calcium loaded chitosan nanoparticles: in vitro evaluation and in vivo pharmacokinetic studies in rabbits

    Directory of Open Access Journals (Sweden)

    Abdul Baquee Ahmed

    2015-06-01

    Full Text Available In this study, we prepared atorvastatin calcium (AVST loaded chitosan nanoparticles to improve the oral bioavailability of the drug. Nanoparticles were prepared by solvent evaporation technique and evaluated for its particle size, entrapment efficiency, zeta potential, in vitro release and surface morphology by scanning electron microscopy (SEM. In addition, the pharmacokinetics of AVST from the optimized formulation (FT5 was compared with marketed immediate release formulation (Atorva(r in rabbits. Particle size of prepared nanoparticles was ranged between 179.3 ± 7.12 to 256.8 ± 8.24 nm with a low polydispersity index (PI value. Zeta potential study showed that the particles are stable with positive values between 13.03 ± 0.32 to 46.90 ± 0.49 mV. FT-IR studies confirmed the absence of incompatibility of AVST with excipient used in the formulations. In vitro release study showed that the drug release was sustained for 48 h. Results of pharmacokinetics study showed significant changes in the pharmacokinetic parameter (2.2 fold increase in AUC of the optimized formulation as compared to marketed formulation (Atorva(r. Thus, the developed nanoparticles evidenced the improvement of oral bioavailability of AVST in rabbit model.

  8. Pharmacokinetics and tolerance study of intravitreal injection of dexamethasone-loaded nanoparticles in rabbits

    OpenAIRE

    Sun, Hongfan

    2009-01-01

    Linhua Zhang1, Yue Li2, Chao Zhang1, Yusheng Wang2, Cunxian Song11Institute of Biomedical Engineering, Peking Union Medical College and Chinese Academy of Medical Sciences, Tianjin, China; 2Department of Ophthalmology, Institute of Ophthalmology of Chinese PLA, Xijing Hospital, Fourth Military Medical University, Xi’an, ChinaAbstract: The aim of the study was to investigate the tolerance and pharmacokinetics of dexamethasone (DEX)-loaded poly(lactic acid–co-glycolic acid) ...

  9. Pharmacokinetics of Chlorin e6-Cobalt Bis(Dicarbollide Conjugate in Balb/c Mice with Engrafted Carcinoma

    Directory of Open Access Journals (Sweden)

    Arthur B. Volovetsky

    2017-11-01

    Full Text Available The necessary precondition for efficient boron neutron capture therapy (BNCT is control over the content of isotope 10B in the tumor and normal tissues. In the case of boron-containing porphyrins, the fluorescent part of molecule can be used for quantitative assessment of the boron content. Study Objective: We performed a study of the biodistribution of the chlorin e6-Cobalt bis(dicarbollide conjugate in carcinoma-bearing Balb/c mice using ex vivo fluorescence imaging, and developed a mathematical model describing boron accumulation and release based on the obtained experimental data. Materials and Methods: The study was performed on Balb/c tumor-bearing mice (CT-26 tumor model. A solution of the chlorin e6-Cobalt bis(dicarbollide conjugate (CCDC was injected into the blood at a dose of 10 mg/kg of the animal’s weight. Analysis of the fluorescence signal intensity was performed at several time points by spectrofluorimetry in blood and by laser scanning microscopy in muscle, liver, and tumor tissues. The boron content in the same samples was determined by mass spectroscopy with inductively coupled plasma. Results: Analysis of a linear approximation between the fluorescence intensity and boron content in the tissues demonstrated a satisfactory value of approximation reliability with a Spearman’s rank correlation coefficient of r = 0.938, p < 0.01. The dynamics of the boron concentration change in various organs, calculated on the basis of the fluorescence intensity, enabled the development of a model describing the accumulation of the studied compound and its distribution in tissues. The obtained results reveal a high level of correspondence between the model and experimental data.

  10. [11]Cocaine: PET studies of cocaine pharmacokinetics, dopamine transporter availability and dopamine transporter occupancy

    International Nuclear Information System (INIS)

    Fowler, Joanna S.; Volkow, Nora D.; Wang, Gene-Jack; Gatley, S. John; Logan, Jean

    2001-01-01

    Cocaine was initially labeled with carbon-11 in order to track the distribution and pharmacokinetics of this powerful stimulant and drug of abuse in the human brain and body. It was soon discovered that [ 11 C]cocaine was not only useful for measuring cocaine pharmacokinetics and its relationship to behavior but that it is also a sensitive radiotracer for dopamine transporter (DAT) availability. Measures of DAT availability were facilitated by the development of a graphical analysis method (Logan Plot) for reversible systems which streamlined kinetic analysis. This expanded the applications of [ 11 C]cocaine to studies of DAT availability in the human brain and allowed the first comparative measures of the degree of DAT occupancy by cocaine and another stimulant drug methylphenidate. This article will summarize preclinical and clinical research with [ 11 C]cocaine

  11. Isolation, characterization, and in rats plasma pharmacokinetic study of a new triterpenoid saponin from Dianthus superbus.

    Science.gov (United States)

    Ren, Yina; Xu, Xiaobao; Zhang, Qianlan; Lu, Yongzhuang; Li, Ximin; Zhang, Lin; Tian, Jingkui

    2017-02-01

    One new oleanolic acid triterpenoid saponin, 3-O-β-D-glucopyranosyl olean-11, 13(18)-diene-23,28-dioic acid, (hereafter referred to as DS-1) was isolated from the traditional Chinese medicinal plant Dianthus superbus (D. superbus). DS-1 plays an important role in the bioactivity of D. superbus. Thus, a sensitive, reliable and accurate reversed-phased liquid chromatography with tandem mass spectrometry (LC-MS/MS) in negative ion mode was developed and validated for the quantification and pharmacokinetic study of DS-1 in rats plasma. The pharmacokinetic profile showed that DS-1 was rapidly absorbed and eliminated in plasma, indicating that significant accumulation of the compound in biological specimen is unlikely. In addition, poor absorption into systemic circulation was observed after oral administration of DS-1, resulting in low absolute bioavailability (0.92 %).

  12. A distributed delay approach for modeling delayed outcomes in pharmacokinetics and pharmacodynamics studies.

    Science.gov (United States)

    Hu, Shuhua; Dunlavey, Michael; Guzy, Serge; Teuscher, Nathan

    2018-04-01

    A distributed delay approach was proposed in this paper to model delayed outcomes in pharmacokinetics and pharmacodynamics studies. This approach was shown to be general enough to incorporate a wide array of pharmacokinetic and pharmacodynamic models as special cases including transit compartment models, effect compartment models, typical absorption models (either zero-order or first-order absorption), and a number of atypical (or irregular) absorption models (e.g., parallel first-order, mixed first-order and zero-order, inverse Gaussian, and Weibull absorption models). Real-life examples were given to demonstrate how to implement distributed delays in Phoenix ® NLME™ 8.0, and to numerically show the advantages of the distributed delay approach over the traditional methods.

  13. Treatment with subcutaneous and transdermal fentanyl: results from a population pharmacokinetic study in cancer patients.

    Science.gov (United States)

    Oosten, Astrid W; Abrantes, João A; Jönsson, Siv; de Bruijn, Peter; Kuip, Evelien J M; Falcão, Amílcar; van der Rijt, Carin C D; Mathijssen, Ron H J

    2016-04-01

    Transdermal fentanyl is effective for the treatment of moderate to severe cancer-related pain but is unsuitable for fast titration. In this setting, continuous subcutaneous fentanyl may be used. As data on the pharmacokinetics of continuous subcutaneous fentanyl are lacking, we studied the pharmacokinetics of subcutaneous and transdermal fentanyl. Furthermore, we evaluated rotations from the subcutaneous to the transdermal route. Fifty-two patients treated with subcutaneous and/or transdermal fentanyl for moderate to severe cancer-related pain participated. A population pharmacokinetic model was developed and evaluated using non-linear mixed-effects modelling. For rotations from subcutaneous to transdermal fentanyl, a 1:1 dose conversion ratio was used while the subcutaneous infusion was continued for 12 h (with a 50 % tapering after 6 h). A 6-h scheme with 50 % tapering after 3 h was simulated using the final model. A one-compartment model with first-order elimination and separate first-order absorption processes for each route adequately described the data. The estimated apparent clearance of fentanyl was 49.6 L/h; the absorption rate constant for subcutaneous and transdermal fentanyl was 0.0358 and 0.0135 h(-1), respectively. Moderate to large inter-individual and inter-occasion variability was found. Around rotation from subcutaneous to transdermal fentanyl, measured and simulated plasma fentanyl concentrations rose and increasing side effects were observed. We describe the pharmacokinetics of subcutaneous and transdermal fentanyl in one patient cohort and report several findings that are relevant for clinical practice. Further research is warranted to study the optimal scheme for rotations from the subcutaneous to the transdermal route.

  14. Determination and pharmacokinetic study of catechin in rat plasma by HPLC

    Directory of Open Access Journals (Sweden)

    Li Xie

    2011-11-01

    Full Text Available A high performance liquid chromatographic method was developed and validated for the quantitative determination of catechin in rat plasma and its pharmacokinetic study after intragastric administration of Catechu and Xiongdanjiangre Wan into SD rats. Plasma samples were prepared by protein precipitation using methanol–5% aqueous zinc sulfate (70:30, v/v as precipitant. Chromatographic separation was achieved on Hypersil C18 column (250 mm×4.6 mm, 10 μm with acetonitrile–water–triethylamine (6:94:0.3, v/v/v, pH 4.0±0.1, adjusted with phosphoric acid as mobile phase, followed by a UV detection at 207 nm. Good linearity was obtained over the range of 0.143–7.15 mg/L of catechin, with correlation coefficient of 0.9992. The method was simple, sensitive, accurate and reproducible and has been successfully applied to the pharmacokinetic study of catechin in rat plasma. Keywords: HPLC, Determination, Pharmacokinetic, Catechin, Rat, Plasma

  15. Pharmacokinetic study of isatin in dog plasma by liquid chromatography tandem mass spectrometry.

    Science.gov (United States)

    Ren, A; Wang, Q; Fang, Z; Gao, M; Wang, H; Zhang, J; Xu, W; Yue, W; Yin, L; Liu, Z; Li, X; Ding, B

    2015-12-01

    A sensitive and selective method was developed and validated to study the pharmacokinetics of isatin. The blood samples were pretreated by protein precipitation method using methanol. Quetiapine was used as an internal standard. After pretreatment, the samples were assayed by LC/MS/MS method and the pharmacokinetic parameters were calculated by WinNonlin 5.2 using non-compartment model. The separation was performed on a Venusil XBP PH column (5 µm, 2.0×100 mm) with an isocratic mobile phase consisted of methanol-water (containing 50 mM ammonium formate) (65:35, v/v) at a flow rate of 0.3 mL/min. The Agilent G6410B triple quadrupole LC/MS system was operated under the multiple reactions monitoring mode (MRM) using the electrospray ionization technique in positive mode. The lower limits of quantification (LLOQ) of the analyte of the method was 10 ng/mL. The method was linear with correlation coefficient >0.995. The intraday and interday accuracy and precision of the assay were acceptable. This method has been applied successfully to a pharmacokinetic study involving the oral and intravenous administration of isatin to beagle dogs.

  16. Allopregnanolone preclinical acute pharmacokinetic and pharmacodynamic studies to predict tolerability and efficacy for Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Ronald W Irwin

    Full Text Available To develop allopregnanolone as a therapeutic for Alzheimer's disease, we investigated multiple formulations and routes of administration in translationally relevant animal models of both sexes. Subcutaneous, topical (transdermal and intranasal, intramuscular, and intravenous allopregnanolone were bolus-administered. Pharmacokinetic analyses of intravenous allopregnanolone in rabbit and mouse indicated that peak plasma and brain levels (3-fold brain/plasma ratios at 5min were sufficient to activate neuroregenerative responses at sub-sedative doses. Slow-release subcutaneous suspension of allopregnanolone displayed 5-fold brain/plasma ratio at Cmax at 30min. At therapeutic doses by either subcutaneous or intravenous routes, allopregnanolone mouse plasma levels ranged between 34-51ng/ml by 30min, comparable to published endogenous human level in the third trimester of pregnancy. Exposure to subcutaneous, topical, intramuscular, and intravenous allopregnanolone, at safe and tolerable doses, increased hippocampal markers of neurogenesis including BrdU and PCNA in young 3xTgAD and aged wildtype mice. Intravenous allopregnanolone transiently and robustly phosphorylated CREB within 5min and increased levels of neuronal differentiation transcription factor NeuroD within 4h. Neurogenic efficacy was achieved with allopregnanolone brain exposure of 300-500hr*ng/g. Formulations were tested to determine the no observable adverse effect level (NOAEL and maximally tolerated doses (MTD in male and female rats by sedation behavior time course. Sex differences were apparent, males exhibited ≥40% more sedation time compared to females. Allopregnanolone formulated in sulfobutyl-ether-beta-cyclodextrin at optimized complexation ratio maximized allopregnanolone delivery and neurogenic efficacy. To establish the NOAEL and MTD for Allo-induced sedation using a once-per-week intravenous regenerative treatment regimen: In female rats the NOAEL was 0.5mg/kg and MTD 2mg

  17. ZD0473 pharmacokinetics in Japanese patients: a Phase I dose-escalation study.

    Science.gov (United States)

    Murakami, H; Tamura, T; Yamada, Y; Yamamoto, N; Ueda, Y; Shimoyama, T; Saijo, N

    2002-12-01

    ZD0473 is new platinum agent that was rationally designed to circumvent platinum resistance and reduce the potential for nephro-and neurotoxicity. This Phase I dose-escalating study investigated the pharmacokinetics, tolerability and efficacy of ZD0473 in Japanese patients with solid, refractory tumours. ZD0473 was administered as a 1-h intravenous infusion every 3 weeks. Nine patients received a total of 16 cycles of ZD0473 (median 1 cycle/patient), with 3 patients treated at each of 3 doses (60, 90, 120 mg/m2). The maximum plasma concentration (C(max)) and the area under the concentration-time curve to infinity (AUC(0-infinity)) increased with dose in a linear fashion for both total platinum and ZD0473 in plasma ultrafiltrate, suggesting that the pharmacokinetics of ZD0473 are linear. Haematological and non-haematological toxicities such as nausea and vomiting were mild (grade 1 or 2) and transient. No clinically significant nephro-, oto- or neurotoxicity was observed. Dose-limiting toxicity (DLT) was not observed and the maximum tolerated dose (MTD) was not identified. ZD0473 treatment showed evidence of disease stabilisation in 3 patients (33%). In conclusion, ZD0473 appears to have linear pharmacokinetics, and an acceptable tolerability profile at doses up to 120 mg/m2 in Japanese patients with refractory solid malignancies. Following evaluation of the data from all the Western trials, the ZD0473 development programme changed and this Japanese trial was stopped.

  18. Pharmacokinetic study of benfotiamine and the bioavailability assessment compared to thiamine hydrochloride.

    Science.gov (United States)

    Xie, Feifan; Cheng, Zeneng; Li, Sanwang; Liu, Xingling; Guo, Xin; Yu, Peng; Gu, Zhenkun

    2014-06-01

    Benfotiamine is a lipid-soluble thiamine precursor which can transform to thiamine in vivo and subsequently be metabolized to thiamine monophosphate (TMP) and thiamine diphosphate (TDP). This study investigated the pharmacokinetic profiles of thiamine and its phosphorylated metabolites after single- and multiple-dose administration of benfotiamine in healthy Chinese volunteers, and assessed the bioavailability of orally benfotiamine administration compared to thiamine hydrochloride. In addition, concentration of hippuric acid in urine which is produced in the transformation process of benfotiamine was determined. The results showed that thiamine and its phosphorylated metabolites exhibited different pharmacokinetic characteristics in plasma, blood and erythrocyte, and one-compartment model provided the best fit for pharmacokinetic profiles of thiamine. The transformation process of benfotiamine to thiamine produced large amount of hippuric acid. No accumulation of hippuric acid was observed after multiple-dose of benfotiamine. Compared to thiamine hydrochloride, the bioavailability of thiamine in plasma and TDP in erythrocyte after oral administration of benfotiamine were 1147.3 ± 490.3% and 195.8 ± 33.8%, respectively. The absorption rate and extent of benfotiamine systemic availability of thiamine were significantly increased indicating higher bioavailability of thiamine from oral dose of benfotiamine compared to oral dose of thiamine hydrochloride. © 2014, The American College of Clinical Pharmacology.

  19. Metabolism and pharmacokinetics of the hypoxic cell radiosensitizer and cytotoxic agent, misonidazole, in C3H mice

    International Nuclear Information System (INIS)

    Chin, J.B.; Rauth, A.M.

    1981-01-01

    Misonidazole, a 2-nitroimidazole, is presently of interest because of its radiosensitizing and toxic effects toward hypoxic tumor cells. The plasma and tissue distribution of misonidazole and various products was studied as a function of time and mode of administration in male C3H mice with KHT tumors. Polarographic measurements of nitro-group species in plasma after intravenous or intraperitoneal misonidazole administration indicated apparent half-lives of 1.0 to 1.5 hr. With an oral dose, a multicomponent curve was obtained. [ 14 C]misonidazole, labeled in the 2-position of the imidazole ring, was widely distributed to all tissues tested after intraperitioneal or oral administration. Paper chromatography of plasma and the water-soluble fraction of spleen, liver, kidney, brain, and KHT tumor tissue showed variations in the proportions of misonidazole, its 0-dimethylation product, the aminoimidazole, and low-R/sub F/ products (including glucuronides). There was radioactivity in the gastrointestinal lumen 1 hr after intravenous injection. These studies indicate that differences exist in total drug levels as well as in the proportions of metabolites present in various tissue types. Thus the radiosensitization and toxicity of misonidazole may depend on the particular tissue or tumor under study

  20. Pharmacokinetic analysis of trichloroethylene metabolism in male B6C3F1 mice: Formation and disposition of trichloroacetic acid, dichloroacetic acid, S-(1,2-dichlorovinyl)glutathione and S-(1,2-dichlorovinyl)-L-cysteine

    International Nuclear Information System (INIS)

    Kim, Sungkyoon; Kim, David; Pollack, Gary M.; Collins, Leonard B.; Rusyn, Ivan

    2009-01-01

    Trichloroethylene (TCE) is a well-known carcinogen in rodents and concerns exist regarding its potential carcinogenicity in humans. Oxidative metabolites of TCE, such as dichloroacetic acid (DCA) and trichloroacetic acid (TCA), are thought to be hepatotoxic and carcinogenic in mice. The reactive products of glutathione conjugation, such as S-(1,2-dichlorovinyl)-L-cysteine (DCVC), and S-(1,2-dichlorovinyl) glutathione (DCVG), are associated with renal toxicity in rats. Recently, we developed a new analytical method for simultaneous assessment of these TCE metabolites in small-volume biological samples. Since important gaps remain in our understanding of the pharmacokinetics of TCE and its metabolites, we studied a time-course of DCA, TCA, DCVG and DCVG formation and elimination after a single oral dose of 2100 mg/kg TCE in male B6C3F1 mice. Based on systemic concentration-time data, we constructed multi-compartment models to explore the kinetic properties of the formation and disposition of TCE metabolites, as well as the source of DCA formation. We conclude that TCE-oxide is the most likely source of DCA. According to the best-fit model, bioavailability of oral TCE was ∼ 74%, and the half-life and clearance of each metabolite in the mouse were as follows: DCA: 0.6 h, 0.081 ml/h; TCA: 12 h, 3.80 ml/h; DCVG: 1.4 h, 16.8 ml/h; DCVC: 1.2 h, 176 ml/h. In B6C3F1 mice, oxidative metabolites are formed in much greater quantities (∼ 3600 fold difference) than glutathione-conjugative metabolites. In addition, DCA is produced to a very limited extent relative to TCA, while most of DCVG is converted into DCVC. These pharmacokinetic studies provide insight into the kinetic properties of four key biomarkers of TCE toxicity in the mouse, representing novel information that can be used in risk assessment.

  1. Pharmacokinetic analysis of trichloroethylene metabolism in male B6C3F1 mice: Formation and disposition of trichloroacetic acid, dichloroacetic acid, S-(1,2-dichlorovinyl)glutathione and S-(1,2-dichlorovinyl)-L-cysteine

    Science.gov (United States)

    Kim, Sungkyoon; Kim, David; Pollack, Gary M.; Collins, Leonard B.; Rusyn, Ivan

    2009-01-01

    Trichloroethylene (TCE) is a well-known carcinogen in rodents and concerns exist regarding its potential carcinogenicity in humans. Oxidative metabolites of TCE, such as dichloroacetic acid (DCA) and trichloroacetic acid (TCA), are thought to be hepatotoxic and carcinogenic in mice. The reactive products of glutathione conjugation, such as S-(1,2-dichlorovinyl)-L-cysteine (DCVC), and S-(1,2-dichlorovinyl) glutathione (DCVG), are associated with renal toxicity in rats. Recently, we developed a new analytical method for simultaneous assessment of these TCE metabolites in small-volume biological samples. Since important gaps remain in our understanding of the pharmacokinetics of TCE and its metabolites, we studied a time-course of DCA, TCA, DCVG and DCVG formation and elimination after a single oral dose of 2100 mg/kg TCE in male B6C3F1 mice. Based on systemic concentration-time data, we constructed multi-compartment models to explore the kinetic properties of the formation and disposition of TCE metabolites, as well as the source of DCA formation. We conclude that TCE-oxide is the most likely source of DCA. According to the best-fit model, bioavailability of oral TCE was ~74%, and the half-life and clearance of each metabolite in the mouse were as follows: DCA: 0.6 hr, 0.081 ml/hr; TCA: 12 hr, 3.80 ml/hr; DCVG: 1.4 hr, 16.8 ml/hr; DCVC: 1.2 hr, 176 ml/hr. In B6C3F1 mice, oxidative metabolites are formed in much greater quantities (~3600 fold difference) than glutathione-conjugative metabolites. In addition, DCA is produced to a very limited extent relative to TCA, while most of DCVG is converted into DCVC. These pharmacokinetic studies provide insight into the kinetic properties of four key biomarkers of TCE toxicity in the mouse, representing novel information that can be used in risk assessment. PMID:19409406

  2. In vitro Cytotoxicity, Pharmacokinetics, Tissue Distribution, and Metabolism of Small-Molecule Protein Kinase D Inhibitors, kb-NB142-70 and kb-NB165-09, in Mice bearing Human Cancer Xenografts

    Science.gov (United States)

    Guo, Jianxia; Clausen, Dana M.; Beumer, Jan H.; Parise, Robert A.; Egorin, Merrill J.; Bravo-Altamirano, Karla; Wipf, Peter; Sharlow, Elizabeth R.; Wang, Qiming Jane; Eiseman, Julie L.

    2012-01-01

    Purpose Protein kinase D (PKD) mediates diverse biological responses including cell growth and survival. Therefore, PKD inhibitors may have therapeutic potential. We evaluated the in vitro cytotoxicity of two PKD inhibitors, kb-NB142-70 and its methoxy analog, kb-NB165-09, and examined their in vivo efficacy and pharmacokinetics. Methods The in vitro cytotoxicities of kb-NB142-70 and kb-NB165-09 were evaluated by MTT assay against PC-3, androgen independent prostate cancer cells, and CFPAC-1 and PANC-1, pancreatic cancer cells. Efficacy studies were conducted in mice bearing either PC-3 or CPFAC-1 xenografts. Tumor-bearing mice were euthanized between 5 and 1440 min after iv dosing, and plasma and tissue concentrations were measured by HPLC-UV. Metabolites were characterized by LC-MS/MS. Results kb-NB142-70 and kb-NB165-09 inhibited cellular growth in the low-mid μM range. The compounds were inactive when administered to tumor-bearing mice. In mice treated with kb-NB142-70, the plasma Cmax was 36.9 nmol/mL and the PC-3 tumor Cmax was 11.8 nmol/g. In mice dosed with kb-NB165-09, the plasma Cmax was 61.9 nmol/mL while the PANC-1 tumor Cmax was 8.0 nmol/g. The plasma half-lives of kb-NB142-70 and kb-NB165-09 were 6 and 14 min, respectively. Both compounds underwent oxidation and glucuronidation. Conclusions kb-NB142-70 and kb-NB165-09 were rapidly metabolized, and concentrations in tumor were lower than those required for in vitro cytotoxicity. Replacement of the phenolic hydroxyl group with a methoxy group increased the plasma half-life of kb-NB165-09 2.3-fold over that of kb-NB142-70. Rapid metabolism in mice suggests that next-generation compounds will require further structural modifications to increase potency and/or metabolic stability. PMID:23108699

  3. Pharmacokinetic Study of Nifedipine in Healthy Adult Male Human ...

    African Journals Online (AJOL)

    Erah

    obtained from the volunteers. Nifedipine (Adalat® capsules, 10 mg, Bayer. Pharmaceuticals, Karachi, Pakistan) was the drug used. The study was conducted in the same subjects in two phases separated by a washout period of one week. Twelve data sets were obtained. Drug administration and blood sampling. A blank ...

  4. Pharmacokinetic studies of active triterpenoid saponins and the total secondary saponin from Anemone raddeana Regel.

    Science.gov (United States)

    Zhang, Dandan; Lei, Tianli; Lv, Chongning; Zhao, Huimin; Xu, Haiyan; Lu, Jincai

    2017-02-15

    The rhizome of Anemone raddeana Regel, a Traditional Chinese Medicine (TCM) which has a robust history treating rheumatism and neuralgia. The total secondary saponin (TSS) from it has demonstrated antitumor activity. In this study, a rapid and validated LC-MS/MS method was developed to simultaneously determine the active compounds (Hederacolchiside A1 and Eleutheroside K). Analytes were separated on a reverse-phase C18 column with acetonitrile-water (5mmol/L ammonium acetate) as the mobile phase. This assay showed acceptable linearity (r>0.99) over the concentration range 5-1000 nmol/L for two analytes. The intra- and inter-day precision was within 8.06% and accuracy was ranged from -3.16% to 3.34% for two analytes. The mean extraction recoveries of analytes and IS from rat plasma were all more than 76.0%. Under the developed analytical conditions, the obtained values of main pharmacokinetic parameters (C max and AUC 0-t ) indicated that the pure compounds were more efficient than the TSS extract in Hederacolchiside A1 and Eleutheroside K absorption. In addition, pharmacokinetic studies of two individual compounds demonstrated their poor oral absorption in rat ( a F%, 0.019-1.521). In the study of absorption and transportation of Hederacolchiside A1 and Eleutheroside K in Caco-2 cell monolayer model, the uptake permeability was in 10 -6 cm/sec range suggesting poor absorption, which confirmed the previous pharmacokinetic profiles in vivo. Interestingly, the uptake ratio of them declined significantly when treated with phloridzin (SGLT1 inhibitor). It indicated that the absorption of Hederacolchiside A1 in intestine was mainly through positive transport and SGLT1 might participate in its active absorption. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Pharmacokinetic Study of Frusemide in Healthy and Cirrhotic Indian Subjects

    Directory of Open Access Journals (Sweden)

    Dr. Yuvrajsing Dhunnoo

    2008-01-01

    Full Text Available Liver cirrhosis is associated with various complications such as ascites and fluid retention, progressing to development of hepatorenal syndrome, further compromising fluid elimination. Frusemide, a loop diuretic is normally administered to relieve fluid retentions. The kinetics of frusemide has not been conclusively reported in the three types of cirrhosis and among Indian subjects. The aim of the current study was to evaluate the kinetics of frusemide among healthy and Child’s A, B and C cirrhosis and compare with earlier data. 24 cirrhotic were selected and classified according to the Child’s-Pugh classification. 12 healthy male volunteers were screened and included in the study. 40 mg of frusemide was administered orally to both groups and blood samples were withdrawn at various intervals of time for a duration of 8 hrs. The amount of frusemide present in plasma was analyzed using HPLC. The volumes of distribution (Vd, area under curve (AUC, systemic clearance (CL, maximum concentration (Cmax, time for maximum concentration (tmax in healthy volunteers were respectively 4.56 ± 0.15 L, 2258 ± 530.7, 4.97 ± 1.67 L/h, 892 ± 49.4 ng/ml, 85.20± 7.49 mins. Corresponding values in Group A were 5.00 ± 0.31 L, 2471 ± 228.6, 6.60 ± 2.90L/h, 1021 ± 47.97 ng/ml and 88.25 V 2.12 mins; in Group B 7.73 ± 1.10 L, 4038 ± 154.7, 8.84 ± 0.45 L/h, 1448 ± 43.20 ng/ml and 120 ± 1.89 mins; In group C cirrhosis 9.69 ± 1.32 L, 4085 ± 131.75, 3.49 ± 1.40 L/h, 1551± 59.02 ng/ml and 185.7 ± 2.68 mins respectively. Significant differences at 1% and 5% were observed among the cirrhotic groups and between healthy v/s cirrhotic patients. Data from current study do not correlate with earlier reports, carried mainly in Western population, due to possibly differences in instrumentation, etc but a possible genetic interplay should not be ruled out. Data from cirrhotic patients could not be effectively compared with earlier studies as kinetics of frusemide

  6. [Pharmacokinetic study of rifampicin in the body of pregnant animals].

    Science.gov (United States)

    Subbotina, N A; Griaznov, N S; Beliavskaia, I V; Chugunova, V I; Sazykin, Iu O

    1979-09-01

    The study on distribution of 14C-rifampicin administered intramuscularly to pregnent animals showed that its concentrations in the blood, liver, kidneys, lungs and other organs did not practically change from those in nonpregnant animals. The concentration of 14C-rifampicin in the fetus organs was much lower than that in the organs of the adult animals. The liver and kidneys of the pregnant animals, as well as the fetus though to a less extent had a capacity for metabolism of 14C-rifampicin. The following products of biotransformation were detected: N-oxide of rifampicin, 25-deacetylrifampicin, 3-formylrifamycin SV and rifamycin SV.

  7. Pharmacokinetic studies of 131 I-stevioside and his metabolites

    International Nuclear Information System (INIS)

    Cardoso, V.N.

    1993-01-01

    Stevia rebaudiana is a shrub widely in Paraguay and Brazil, belonging to the compositae family. The leaves of this plant contain large amounts of stevioside. Since the use of stevioside as sugar substitute continues to increase, the purpose of this study is to investigate the biological distribution, excretion and the possibility of stevioside to be degraded to steviol 'in vitro'. 131 -I-stevioside (1,10 MBq) was i.v. injected in Wistar male rats its distribution in the body and metabolism were studied. The highest concentration of radioactivity was observed in the liver and the small intestine after 10 and 120 minutes respectively. RP-HPLC analysis of the bile showed that steviol appeared as a major metabolite, representing 47,3% of the radioactivity while stevioside represented 37,3% and the remaining 15,4% was due to an unidentified metabolite. The results showed that stevioside was partially degraded 'in vivo' to steviol and other metabolite, and that part of the radioactivity was absorbed from the small intestine. (author)

  8. Oral microemulsions of paclitaxel: in situ and pharmacokinetic studies.

    Science.gov (United States)

    Nornoo, Adwoa O; Zheng, Haian; Lopes, Luciana B; Johnson-Restrepo, Boris; Kannan, Kurunthachalam; Reed, Rachel

    2009-02-01

    The overall goal of this study was to develop cremophor-free oral microemulsions of paclitaxel (PAC) to enhance its permeability and oral absorption. The mechanism of this enhancement, as well as characteristics of the microemulsions relevant to the increase in permeability and absorption of the low solubility, low permeability PAC was investigated. Phase diagrams were used to determine the macroscopic phase behavior of the microemulsions and to compare the efficiency of different surfactant-oil mixtures to incorporate water. The microemulsion region on the phase diagrams utilizing surfactant-myvacet oil combinations was in decreasing order: lecithin: butanol: myvacet oil (LBM, 48.5%)>centromix CPS: 1-butanol: myvacet oil (CPS, 45.15%)>capmul MCM: polysorbate 80: myvacet oil (CPM, 27.6%)>capryol 90: polysorbate 80: myvacet oil (CP-P80, 23.9%)>capmul: myvacet oil (CM, 20%). Oil-in-water (o/w) microemulsions had larger droplet sizes (687-1010 nm) than the water-in-oil (w/o) microemulsions (272-363 nm) when measured using a Zetasizer nano series particle size analyzer. Utilizing nuclear magnetic resonance spectroscopy (NMR), the self-diffusion coefficient (D) of PAC in CM, LBM and CPM containing 10% of deuterium oxide (D(2)O) was 2.24x10(-11), 1.97x10(-11) and 0.51x10(-11) m(2)/s, respectively. These values indicate the faster molecular mobility of PAC in the two w/o microemulsions (CM and LBM) than the o/w microemulsion--CPM. The in situ permeability of PAC through male CD-IGS rat intestine was 3- and 11-fold higher from LBM and CM, respectively, than that from the control clinical formulation, Taxol (CE, cremophor: ethanol) in a single pass perfusion study. PAC permeability was significantly increased in the presence of the pgp/CYP3A4 inhibitor cyclosporine A (CsA). This enhancement may be attributed to the pgp inhibitory effect of the surfactants, oil and/or the membrane perturbation effect of the surfactants. The oral disposition of PAC in CM, LBM and CPM compared

  9. Lisdexamfetamine: A pharmacokinetic review.

    Science.gov (United States)

    Comiran, Eloisa; Kessler, Félix Henrique; Fröehlich, Pedro Eduardo; Limberger, Renata Pereira

    2016-06-30

    Lisdexamfetamine (LDX) is a d-amphetamine (d-AMPH) pro-drug used to treat Attention Deficit and Hyperactivity Disorder (ADHD) and Binge Eating Disorder (BED) symptoms. The in vivo pharmacodynamics of LDX is the same as that of its active product d-AMPH, although there are a few qualitative and quantitative differences due to pharmacokinetics. Due to the specific pharmacokinetics of the long-acting stimulants, this article revises the pharmacokinetic studies on LDX, the newest amphetamine pro-drug. The Medline/Pubmed, Science Direct and Biblioteca Virtual em Saúde (Lilacs and Ibecs) (2007-2016) databases were searched for articles and their list of references. As for basic pharmacokinetics studies, since LDX is a newly developed medication, there are few results concerning biotransformation, distribution and the use of different biological matrices for analysis. This is the first robust review on this topic, gathering data from all clinical pharmacokinetics studies available in the literature. The particular pharmacokinetics of LDX plays a major role in studying this pro-drug, since this knowledge was essential to understand some reports on clinical effects in literature, e.g. the small likelihood of reducing the effect by interactions, the effect of long duration use and the still questionable reduction of the potential for abuse. In general the already well-known pharmacokinetic properties of amphetamine make LDX relatively predictable, simplifying the use of LDX in clinical practice. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Pharmacokinetic and bioavailability studies of commercially available simvastatin tablets in healthy and moderately hyperlipidaemic human subjects

    International Nuclear Information System (INIS)

    Ahmed, M.; Qamar-uz-Zaman, M.; Madni, A.; Usman, M.; Atif, M.; Akhtar, N.; Murtaza, G.

    2011-01-01

    Simvastatin, an analogue of Lovostatin, is a HMG.CoA reductase inhibitor. It is widely used in the treatment of hyperlipidaemia and coronary heart disease (CHD) with low incidence of myopathy and rhabdomyolysis. As these diseases may alter the pharmacokinetics of drugs, the present study was aimed to elaborate the variation in the pharmacokinetics and bioavailability of simvastatin in local healthy and moderately hyperlipidaemic population. Open, single dose and parallel design was applied to study. A total of 36 male volunteers were used for healthy and moderately hyperlipidaemic groups (n 18 for each) in this study on the basis of screening procedures, body chemistry and physical examination. Simvastatin 40 mg tablets (Saista 40, Bosch, Pakistan) were administered to over-night fasted volunteers. Blood samples were collected before dosing (zero time) and at regular intervals of time. The plasma samples were processed through a liquid-liquid extraction procedure and assayed by using HPLC consisting reversed phase C/sub 18/ column (ZORBAX, 4.6 x 150 mm, 5 mu m), UV detector set at 238 nm. The mobile phase consisted of the mixture of 0.025 M sodium dihydrogen phosphate (pH 4.5): acetonitrile (35: 65, v/v) which was pumped at a flow rate of 1.5 mL.min/sup -1/. The retention time of simvastatin was 7.5 minutes. The plasma drug concentration-time profiles of both groups were found significantly (P 0.05) difference between the values of following pharmacokinetic parameters in healthy and hyperlipidaemic volunteers i.e. C/sub max/, t/sub max/, AUC/sub 0-fi), AUMC/sub 0-enfinity), MRT, t/sub 1/2/, Cl/sub t /and K/sub e/. This study confirmed no significant (P > 0.05) difference in pharmacokinetics and bioavailability parameters after the administration of a single oral dose of 40 mg simvastatin (cholesterol lowering drug) to healthy and moderately hyperlipidaemic volunteers. (author)

  11. Proposed clinical trial studying the pharmacokinetics of B.S.H

    International Nuclear Information System (INIS)

    Harkness, W.F.J.

    1988-01-01

    There has been considerable interest in BNCT at Oxford for several years, which has been facilitated by the proximity of the clinical Departments of Neurosurgery and Radiotherapy as well as the Radiobiology unit and the Atomic Energy Research Establishment at Harwell. Each unit has been collaborating over this time with the end objective of a therapeutic facility at Harwell. In the Department of Neurosurgery, they are about to embark on a clinical study of the pharmacokinetics of a boron compound. This is a non-therapeutic trial as they cannot offer a neutron facility at Harwell as yet. Full approval of the Ethical Committee has been granted

  12. Metabolic and pharmacokinetic studies of scutellarin in rat plasma, urine, and feces.

    Science.gov (United States)

    Xing, Jian-feng; You, Hai-sheng; Dong, Ya-lin; Lu, Jun; Chen, Si-ying; Zhu, Hui-fang; Dong, Qian; Wang, Mao-yi; Dong, Wei-hua

    2011-05-01

    To study the metabolic and pharmacokinetic profile of scutellarin, an active component from the medical plant Erigeron breviscapus (Vant) Hand-Mazz, and to investigate the mechanisms underlying the low bioavailability of scutellarin though oral or intravenous administration in rats. HPLC method was developed for simultaneous detection of scutellarin and scutellarein (the aglycone of scutellarin) in rat plasma, urine and feces. The in vitro metabolic stability study was carried out in rat liver microsomes from different genders. After a single oral dose of scutellarin (400 mg/kg), the plasma concentrations of scutellarin and scutellarein in female rats were significantly higher than in male ones. Between the female and male rats, significant differences in AUC, t(max2) and C(max2) for scutellarin were found. The pharmacokinetic parameters of scutellarin in the urine also showed significant gender differences. After a single oral dose of scutellarin (400 mg/kg), the total percentage excretion of scutellarein in male and female rats was 16.5% and 8.61%, respectively. The total percentage excretion of scutellarin and scutellarein in the feces was higher with oral administration than with intravenous administration. The in vitro t(1/2) and CL(int) value for scutellarin in male rats was significantly higher than that in female rats. The results suggest that a large amount of ingested scutellarin was metabolized into scutellarein in the gastrointestinal tract and then excreted with the feces, leading to the extremely low oral bioavailability of scutellarin. The gender differences of pharmacokinetic parameters of scutellarin and scutellarein are due to the higher CL(int) and lower absorption in male rats.

  13. Pharmacokinetics: curiosity or cure

    International Nuclear Information System (INIS)

    Notari, R.E.

    1979-01-01

    What is the fate of a drug from the time of its introduction into the body to the end of its duration. Pharmacokinetic studies are often designed to provide an answer to this question. But this question may be asked of any drug and research that is limited to answering it will remain empirical. Pharmacokinetic studies can provide answers to many other drug-related questions. In doing so pharmacokinetic research has the potential of improving drug therapy as well as the design and evaluation of drugs. While significant contributions can be cited, the future of pharmacokinetics depends upon its increased impact on clinical practice and drug design. How can a molecule be tailored for site specificity. Can chemical modification selectively alter absorption, distribution, metabolism, binding or excretion. In what new ways can pharmacokinetic information increase the predictability of drug therapy. Such questions, to which pharmacokinetics should provide answers, are numerous and easily identified. But the definitive studies are difficult both to create and conduct. Whether or not pharmacokinetics can achieve its full potential will depend upon the extent to which it can provide answers to these currently unanswered questions

  14. Pharmacokinetics of orally administered low-dose rapamycin in healthy dogs: A pilot study

    Science.gov (United States)

    Larson, Jeanne C.; Allstadt, Sara D.; Fan, Timothy M.; Khanna, Chand; Lunghofer, Paul J.; Hansen, Ryan J.; Gustafson, Daniel L.; Legendre, Alfred M.; Galyon, Gina D.; LeBlanc, Amy K.; Martin-Jimenez, Tomas

    2017-01-01

    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 (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 non-compartmental 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 ng/mL. The optimal dose and administration frequency of rapamcyin required to achieve therapeutic effects in tumor-bearing dogs, as well as toxicity after chronic dosing, needs to be determined. PMID:26709938

  15. Improved physiologically based pharmacokinetic model for oral exposures to chromium in mice, rats, and humans to address temporal variation and sensitive populations

    Energy Technology Data Exchange (ETDEWEB)

    Kirman, C.R., E-mail: ckirman@summittoxicology.com [Summit Toxicology, PO Box 3209, Bozeman, MT 59715 (United States); Suh, M.; Proctor, D.M. [ToxStrategies, Mission Viejo, CA (United States); Hays, S.M. [Summit Toxicology, PO Box 3209, Bozeman, MT 59715 (United States)

    2017-06-15

    A physiologically based pharmacokinetic (PBPK) model for hexavalent chromium [Cr(VI)] in mice, rats, and humans developed previously (Kirman et al., 2012, 2013), was updated to reflect an improved understanding of the toxicokinetics of the gastrointestinal tract following oral exposures. Improvements were made to: (1) the reduction model, which describes the pH-dependent reduction of Cr(VI) to Cr(III) in the gastrointestinal tract under both fasted and fed states; (2) drinking water pattern simulations, to better describe dosimetry in rodents under the conditions of the NTP cancer bioassay; and (3) parameterize the model to characterize potentially sensitive human populations. Important species differences, sources of non-linear toxicokinetics, and human variation are identified and discussed within the context of human health risk assessment. - Highlights: • An improved version of the PBPK model for Cr(VI) toxicokinetics was developed. • The model incorporates data collected to fill important data gaps. • Model predictions for specific age groups and sensitive subpopulations are provided. • Implications to human health risk assessment are discussed.

  16. A randomised cross-over pharmacokinetic bioavailability study of synthetic versus kiwifruit-derived vitamin C.

    Science.gov (United States)

    Carr, Anitra C; Bozonet, Stephanie M; Vissers, Margreet C M

    2013-11-11

    Kiwifruit are a rich source of vitamin C and also contain numerous phytochemicals, such as flavonoids, which may influence the bioavailability of kiwifruit-derived vitamin C. The aim of this study was to compare the relative bioavailability of synthetic versus kiwifruit-derived vitamin C using a randomised cross-over pharmacokinetic study design. Nine non-smoking males (aged 18-35 years) received either a chewable tablet (200 mg vitamin C) or the equivalent dose from gold kiwifruit (Actinidia chinensis var. Sungold). Fasting blood and urine were collected half hourly to hourly over the eight hours following intervention. The ascorbate content of the plasma and urine was determined using HPLC with electrochemical detection. Plasma ascorbate levels increased from 0.5 h after the intervention (P = 0.008). No significant differences in the plasma time-concentration curves were observed between the two interventions (P = 0.645). An estimate of the total increase in plasma ascorbate indicated complete uptake of the ingested vitamin C tablet and kiwifruit-derived vitamin C. There was an increase in urinary ascorbate excretion, relative to urinary creatinine, from two hours post intervention (P vitamin C tablet and kiwifruit arms, respectively. Overall, our pharmacokinetic study has shown comparable relative bioavailability of kiwifruit-derived vitamin C and synthetic vitamin C.

  17. Studies of (±)-3,4-methylenedioxymethamphetamine (MDMA) metabolism and disposition in rats and mice: relationship to neuroprotection and neurotoxicity profile.

    Science.gov (United States)

    Mueller, Melanie; Maldonado-Adrian, Concepcion; Yuan, Jie; McCann, Una D; Ricaurte, George A

    2013-02-01

    The neurotoxicity of (±)-3,4-methylenedioxymethamphetamine (MDMA; "Ecstasy") is influenced by temperature and varies according to species. The mechanisms underlying these two features of MDMA neurotoxicity are unknown, but differences in MDMA metabolism have recently been implicated in both. The present study was designed to 1) assess the effect of hypothermia on MDMA metabolism, 2) determine whether the neuroprotective effect of hypothermia is related to inhibition of MDMA metabolism, and 3) determine if different neurotoxicity profiles in mice and rats are related to differences in MDMA metabolism and/or disposition in the two species. Rats and mice received single neurotoxic oral doses of MDMA at 25°C and 4°C, and body temperature, pharmacokinetic parameters, and serotonergic and dopaminergic neuronal markers were measured. Hypothermia did not alter MDMA metabolism in rats and only modestly inhibited MDMA metabolism in mice; however, it afforded complete neuroprotection in both species. Rats and mice metabolized MDMA in a similar pattern, with 3,4-methylenedioxyamphetamine being the major metabolite, followed by 4-hydroxy-3-methoxymethamphetamine and 3,4-dihydroxymethamphetamine, respectively. Differences between MDMA pharmacokinetics in rats and mice, including faster elimination in mice, did not account for the different profile of MDMA neurotoxicity in the two species. Taken together, the results of these studies indicate that inhibition of MDMA metabolism is not responsible for the neuroprotective effect of hypothermia in rodents, and that different neurotoxicity profiles in rats and mice are not readily explained by differences in MDMA metabolism or disposition.

  18. Study on influence of piperine treatment on the pharmacokinetics of diclofenac in healthy volunteers.

    Science.gov (United States)

    Bedada, Satish Kumar; Boga, Praveen Kumar; Kotakonda, Harish Kaushik

    2017-02-01

    1. Diclofenac sodium (DIC) is a widely used anti-inflammatory drug and its administration in humans receiving long-term therapy with herbal drugs containing piperine (PIP) may occur, which leads to drug-phytochemical interactions. The purpose of the present study was to investigate the influence of PIP treatment on the pharmacokinetics of DIC in healthy volunteers. 2. The open-label, two period, sequential study was conducted in 12 healthy volunteers. PIP 20 mg was administered once daily for 10 days during treatment phase. A single dose of DIC 100 mg was administered during control and after treatment phases under fasting conditions. The blood samples were collected after DIC dosing at predetermined time intervals and analyzed by HPLC. 3. Treatment with PIP significantly enhanced maximum plasma concentration (C max ) (2.24-3.68 μg/mL, p pharmacokinetics of DIC might be attributed to PIP mediated inhibition of CYP2C9 enzyme, which indicates the clinically significant interaction present between DIC and PIP. Therefore, the combination therapy of DIC along with PIP may represent a novel approach to reduce dosage and result in reduced incidence of gastrointestinal side effects seen with DIC alone at higher doses.

  19. Pharmacokinetics study of bio-adhesive tablet of Panax notoginseng saponins

    Directory of Open Access Journals (Sweden)

    Feng Hanzhou

    2011-06-01

    Full Text Available Abstract Panax notoginseng saponin (PNS is the main active gradient of Chinese traditional medicine Panax notoginseng. Although its prominent therapeutic efficacy has been demonstrated by various researchers, the broader application is restricted by the low bioavailability of PNS. This article aims to discuss PNS's plasma pharmacokinetics after oral administration of bio-adhesive tablet of PNS to beagle dogs and improve its bioavailability in comparison with normal tablet. The bio-adhesive tablet was prepared according to our previous patent, using chitosan as main excipient. A simple and sensitive LC-MS/MS combined with solid-phase extraction (SPE method for the analysis of PNS in dog's plasma was developed in our previous study, and was validated to apply in the pharmacokinetics study in this work. Three ingredients: Notoginsenoside R1 (R1, Ginsenoside Rg1 (Rg1 and Ginsenoside Rb1 (Rb1 (Figure 1, were chosen as indicators of PNS to analyze it in vivo. Statistically significant increase (P

  20. [The enantioselective pharmacokinetic study of desvenlafaxine sustained release tablet in Chinese healthy male volunteers after oral administration].

    Science.gov (United States)

    Chen, Yin-xia; Du, Jiang-bo; Zhang, Yi-fan; Chen, Xiao-yan; Zhong, Da-fang

    2015-04-01

    A chiral LC-MS/MS method for the simultaneous analysis of desvenlafaxine (DVS) enantiomers in human plasma was developed and applied to a pharmacokinetic study on 12 Chinese healthy volunteers. d6-Desvenlafaxine was used as internal standard (IS). Chromatographic separation was performed on the Astec Chirobiotic V chiral column (150 mm x 4.6 mm, 5 μm). The assay was linear over the concentration range of 0.500-150 ng x mL(-1) for both enantiomers (r2 > 0.99). The method was successfully applied to a stereoselective pharmacokinetic study of 100 mg desvenlafaxine sustained release tablets on 12 Chinese healthy volunteers under fasting conditions. The results showed that the pharmacokinetic parameters were similar to both enantiomers in Chinese healthy volunteers. The AUC(0-t), and C(max) of the two enantiomers were about 1.5 times higher than those of blacks and whites reported in the literature.

  1. Pharmacokinetic Studies of Chinese Medicinal Herbs Using an Automated Blood Sampling System and Liquid Chromatography-mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Yu-Tse Wu

    2012-01-01

    Full Text Available The safety of herbal products is one of the major concerns for the modernization of traditional Chinese medicine, and pharmacokinetic data of medicinal herbs guide us to design the rational use of the herbal formula. This article reviews the advantages of the automated blood sampling (ABS systems for pharmacokinetic studies. In addition, three commonly used sample preparative methods, protein precipitation, liquid-liquid extraction and solid-phase extraction, are introduced. Furthermore, the definition, causes and evaluation of matrix effects in liquid chromatography-mass spectrometry (LC/MS analysis are demonstrated. Finally, we present our previous works as practical examples of the application of ABS systems and LC/MS for the pharmacokinetic studies of Chinese medicinal herbs.

  2. STUDIES ON TRANSMISSIBLE LYMPHOID LEUCEMIA OF MICE.

    Science.gov (United States)

    Furth, J; Strumia, M

    1931-04-30

    Lymphoid leucemia of the mouse is readily transmitted by intravenous inoculations. The majority of the mice inoculated successfully develop leucemic, a smaller number of them, aleucemic lymphadenosis. The data presented favor the view that leucemic and aleucemic lymphadenosis are essentially the same condition. Leucemia produced by transmission is preceded by an aleucemic stage, in which the lymph nodes and the spleen are uniformly enlarged, and the white blood count and the percentage of lymphocytes are within the normal range but immature lymphocytes are numerous in the circulating blood. Young as well as old mice may develop leucemia if leucotic material enters their circulation. Studies of transmissible leucemia favor the view that leucemia of mammals is a neoplastic disease. The basic problem of leucemia would seem to be determination of the factors that bring about a malignant transformation of lymphoid cells.

  3. Enantioselective HPLC determination of oxiracetam enantiomers and application to a pharmacokinetic study in beagle dogs.

    Science.gov (United States)

    Zhang, Qiuyang; Yang, Wei; Zhang, Qing; Yang, Yue; Li, Junxiu; Lu, Yang; Zheng, Yi; He, Jiake; Zhao, Di; Chen, Xijing

    2015-07-01

    An enantioselective high-performance liquid chromatography method was developed and validated for the determination of oxiracetam enantiomers, a cognition and memory enhancer, in beagle dog plasma. The plasma samples were prepared by methanol extraction from 200μL plasma, and then the baseline resolution was achieved on a Chiralpak ID column (250mm×4.6mm, 5μm) with mobile phase of hexane-ethanol-trifluoroacetic acid (78:22:0.1, v/v/v) at flow rate of 1.0mL/min. The column elute was monitored using ultraviolet detection at 214nm. The method was linear over concentration range 0.50-100μg/mL for both enantiomers. The relative standard deviation values for intra- and inter-day precision were 0.78-13.61 and 0.74-8.92% for (R)- and (S)-oxiracetam, respectively. The relative error values of accuracy ranged from -4.74 to 10.48% for (R)-oxiracetam and from -0.19 to 11.48% for (S)-oxiracetam. The method was successfully applied to a pharmacokinetic study of individual enantiomer and racemic oxiracetam in beagle dogs after oral administration. The disposition of the two enantiomers was not stereoselective and chiral inversion was not observed in beagle dogs. The pharmacokinetic profiles of (S)-oxiracetam were similar with racemic oxiracetam in beagle dogs. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A general method to determine sampling windows for nonlinear mixed effects models with an application to population pharmacokinetic studies.

    Science.gov (United States)

    Foo, Lee Kien; McGree, James; Duffull, Stephen

    2012-01-01

    Optimal design methods have been proposed to determine the best sampling times when sparse blood sampling is required in clinical pharmacokinetic studies. However, the optimal blood sampling time points may not be feasible in clinical practice. Sampling windows, a time interval for blood sample collection, have been proposed to provide flexibility in blood sampling times while preserving efficient parameter estimation. Because of the complexity of the population pharmacokinetic models, which are generally nonlinear mixed effects models, there is no analytical solution available to determine sampling windows. We propose a method for determination of sampling windows based on MCMC sampling techniques. The proposed method attains a stationary distribution rapidly and provides time-sensitive windows around the optimal design points. The proposed method is applicable to determine sampling windows for any nonlinear mixed effects model although our work focuses on an application to population pharmacokinetic models. Copyright © 2012 John Wiley & Sons, Ltd.

  5. [Role of food interaction pharmacokinetic studies in drug development. Food interaction studies of theophylline and nifedipine retard and buspirone tablets].

    Science.gov (United States)

    Drabant, S; Klebovich, I; Gachályi, B; Renczes, G; Farsang, C

    1998-09-01

    Due to several mechanism, meals may modify the pharmacokinetics of drug products, thereby eliciting to clinically significant food interaction. Food interactions with the drug substance and with the drug formulation should be distinguished. Food interaction of different drug products containing the same active ingredient can be various depending on the pharmaceutical formulation technology. Particularly, in the case of modified release products, the food/formulation interaction can play an important role in the development of food interaction. Well known example, that bioavailability of theophylline can be influenced in different way (either increased, decreased or unchanged) by concomitant intake of food in the case of different sustained release products. The role and methods of food interaction studies in the different kinds of drug development (new chemical entity, modified release products, generics) are reviewed. Prediction of food effect response on the basis of the physicochemical and pharmacokinetic characteristics of the drug molecule or formulations is discussed. The results of three food interaction studies carried out the products of EGIS Pharmaceuticals Ltd. are also reviewed. The pharmacokinetic parameters of theophyllin 400 mg retard tablet were practically the same in both fasting condition and administration after consumption of a high fat containing standard breakfast. The ingestion of a high fat containing breakfast, increased the AUC of nifedipine from 259.0 +/- 101.2 ng h/ml to 326.7 +/- 122.5 ng h/ml and Cmax from 34.5 +/- 15.9 ng/ml to 74.3 +/- 23.9 ng/ml in case of nifedipine 20 mg retard tablet, in agreement with the data of literature. The statistical evaluation indicated significant differences between the pharmacokinetic parameters in the case of two administrations (before and after meal). The effect of a high fat containing breakfast for a generic version of buspiron 10 mg tablet and the bioequivalence after food consumption were

  6. The safety and pharmacokinetics of a reverse transcriptase inhibitor, 3TC, in patients with HIV infection: a phase I study

    NARCIS (Netherlands)

    van Leeuwen, R.; Lange, J. M.; Hussey, E. K.; Donn, K. H.; Hall, S. T.; Harker, A. J.; Jonker, P.; Danner, S. A.

    1992-01-01

    To determine the safety and pharmacokinetics of the nucleoside analogue, 3TC. A Phase I, open-label, single-centre study. Twenty asymptomatic, HIV-infected male patients with CD4 lymphocyte counts < 500 x 10(6)/l who had not received previous antiretroviral therapy completed the study. Each patient

  7. A safety and pharmacokinetic dosing study of glucagon-like peptide 2 in infants with intestinal failure

    DEFF Research Database (Denmark)

    Sigalet, David L; Brindle, Mary E; Boctor, Dana

    2017-01-01

    BACKGROUND & AIMS: Glucagon-like peptide 2 (GLP-2) analogues are approved for adults with intestinal failure (IF), but no studies have included infants. This study examined the pharmacokinetics (PK), safety, and nutritional effects of GLP-2 in infants with IF. METHODS: With parental consent (Health...

  8. Pharmacokinetics of Snake Venom

    OpenAIRE

    Suchaya Sanhajariya; Stephen B. Duffull; Geoffrey K. Isbister

    2018-01-01

    Understanding snake venom pharmacokinetics is essential for developing risk assessment strategies and determining the optimal dose and timing of antivenom required to bind all venom in snakebite patients. This review aims to explore the current knowledge of snake venom pharmacokinetics in animals and humans. Literature searches were conducted using EMBASE (1974–present) and Medline (1946–present). For animals, 12 out of 520 initially identified studies met the inclusion criteria. In general, ...

  9. Pharmacokinetic study of atorvastain after single dose administration among pakistani population

    International Nuclear Information System (INIS)

    Maqsood, I.; Najmi, M. H.; Mazhar, W.; Janjua, A.; Tayyaba, B.; Sabah, S.; Bader, Z.

    2017-01-01

    Objective: To obtain pharmacokinetic data of Orvastin, a newly launched formulation of atorvastatin, in healthy males of Pakistan. Study Design: It was quasi-experimental design. Place and Duration of Study: Study was conducted at Centre for Research in Experimental and Applied Medicine (CREAM) Army Medical College, Rawalpindi and duration of study was about ten months. Material and Methods: Twenty-four healthy male subjects were taken conveniently from Pakistani population. Two tablets of Orvastin, each containing atorvastatin 40mg, were administered orally as a single dose. Multiple blood samples were taken with small gaps in between up to the period of 48hrs. High Performance Liquid Chromatography (HPLC) with UV-detector was used for quantification of atorvastatin in plasma; wavelength of UV-detector was adjusted at 247nm. Mobile phase was made up of 60 percent acetonitrile and 40 percent 0.05M sodium phosphate buffer. Flow rate of mobile phase was maintained at 1.5ml/min with 5.5 pH. Progesterone was used as an internal standard. Stock solutions of atorvastatin were made by dissolving it into methanol and acetonitrile was used for making stock solution of progesterone. Calibration curves were made for atorvastatin and internal standard from oncentration time data, values for time to achieve maximum plasma concentration. (Tmax) and maximum plasma concentration (Cmax) were directly calculated. Computer program (APO, MW PHARM, and Ver. 3.60) was used for calculation of pharmacokinetic profile of atorvastatin. Results: Atorvastatin was detected in plasma samples of all volunteers. The absorption rate constant (Ka) was 0.41 l/hr. Cmax was 26.69 ± 6.67 µg/l and Tmax was 3.33 ± 0.41 hrs. Apparent volume of distribution (Vd), of atorvastatin, was 3244.84 ± 1237.36 liters. The elimination rate constant was 0.15 l/hr. Elimination half-life of atorvastatin was 6.14 hours. Trapezoidal rule was used for calculation of AUC /sub 0-48/ and AUC /sub 0-∞/ and it was found

  10. Pharmacokinetics of 450 mg ropivacaine with and without epinephrine for combined femoral and sciatic nerve block in lower extremity surgery. A pilot study

    NARCIS (Netherlands)

    Schoenmakers, K.P.; Vree, T.B.; Jack, N.T.; Bemt, B.J.F van den; Limbeek, J. van; Stienstra, R.

    2013-01-01

    AIMS: No pharmacokinetic data exist on doses of ropivacaine larger than 300 mg for peripheral nerve block in man, although in clinical practice higher doses are frequently used. The purpose of the present study was to describe the pharmacokinetic profile in serum of 450 mg ropivacaine with and

  11. Pharmacokinetics, tissue distribution, and metabolites of a polyvinylpyrrolidone-coated norcantharidin chitosan nanoparticle formulation in rats and mice, using LC-MS/MS

    Directory of Open Access Journals (Sweden)

    Ding XY

    2012-04-01

    Full Text Available Xin-Yuan Ding1, Cheng-Jiao Hong2, Yang Liu1, Zong-Lin Gu1, Kong-Lang Xing1, Ai-Jun Zhu1, Wei-Liang Chen1, Lin-Seng Shi1, Xue-Nong Zhang1, Qiang Zhang31Department of Pharmaceutics, College of Pharmaceutical science, Soochow University, Suzhou, 2Jiang Su Provincial Key Laboratory of Radiation Medicine and Protection, Suzhou, 3Department of Pharmaceutics, School of Pharmaceutical Science, Peking University, Beijing, People’s Republic of ChinaAbstract: A novel formulation containing polyvinylpyrrolidone (PVP K30-coated norcantharidin (NCTD chitosan nanoparticles (PVP–NCTD–NPs was prepared by ionic gelation between chitosan and sodium tripolyphosphate. The average particle size of the PVP–NCTD–NPs produced was 140.03 ± 6.23 nm; entrapment efficiency was 56.33% ± 1.41%; and drug-loading efficiency was 8.38% ± 0.56%. The surface morphology of NCTD nanoparticles (NPs coated with PVP K30 was characterized using various analytical techniques, including X-ray diffraction and atomic force microscopy. NCTD and its metabolites were analyzed using a sensitive and specific liquid chromatography-tandem mass spectrometry method with samples from mice and rats. The results indicated the importance of the PVP coating in controlling the shape and improving the entrapment efficiency of the NPs. Pharmacokinetic profiles of the NCTD group and PVP–NCTD–NP group, after oral and intravenous administration in rats, revealed that relative bioavailabilities were 173.3% and 325.5%, respectively. The elimination half-life increased, and there was an obvious decrease in clearance. The tissue distribution of NCTD in mice after the intravenous administration of both formulations was investigated. The drug was not quantifiable at 6 hours in all tissues except for the liver and kidneys. The distribution of the drug in the liver and bile was notably improved in the PVP–NCTD–NP group. The metabolites and excretion properties of NCTD were investigated by analyzing

  12. A Comparative Pharmacokinetics Study of the Anti-Parkinsonian Drug Pramipexole

    Directory of Open Access Journals (Sweden)

    Ratih S. I. Putri

    2016-11-01

    Full Text Available The present study aimed to compare pharmacokinetic parameters of two pramipexole 0.25 mg formulations in order to show bioequivalence. The study was conducted in a randomized, open-label, two-period, two-sequence, and crossover design, involving 23 healthy volunteers. One of the 0.25 mg formulations of pramipexole evaluated in the study was manufactured by PT Dexa Medica, Palembang, Indonesia, the other, used as the reference, by Boehringer Ingelheim Pharma GmbH & Co. KG, Ingelheim am Rhein, Germany. All eligible subjects were required to fast before each drug administration period, which was separated by a one-week washout period. Pramipexole concentrations in plasma were assayed using a validated ultra performance liquid chromatography with mass spectrometry (UPLC-MS/MS detector. The evaluated pharmacokinetic parameters included the area under the plasma concentration curve from time zero to the last observed measurable concentration (AUC0-t, the area under the plasma concentration curve extrapolated to infinite time (AUC0-∞, the maximum plasma concentration (Cmax, the time to reach Cmax (tmax, and the plasma concentration half-life (t1/2. To evaluate the bioequivalence of those two pramipexole formulations, 90% confidence intervals (CIs for geometric mean ratios of both formulations were calculated for AUC and Cmax parameters, while tmax and t1/2 differences were analyzed on the non-transformed data using Wilcoxon matched-pairs and a Student’s paired t-test, respectively. The 90% CIs for the geometric mean ratios of the two pramipexole formulations were 95.89% (90.73%–101.34%, 95.53% (89.75%–101.68%, and 92.11% (84.35%–100.58% for AUC0-t, AUC0-∞, and Cmax, respectively. There were no statistically significant differences for tmax and t1/2 between the two pramipexole formulations. It is concluded that two pramipexole formulations in this study were bioequivalent.

  13. A Comparative Pharmacokinetics Study of the Anti-Parkinsonian Drug Pramipexole.

    Science.gov (United States)

    Putri, Ratih S I; Setiawati, Effi; Aziswan, Syifa A; Ong, Fenny; Tjandrawinata, Raymond R; Susanto, Liana W

    2016-11-18

    The present study aimed to compare pharmacokinetic parameters of two pramipexole 0.25 mg formulations in order to show bioequivalence. The study was conducted in a randomized, open-label, two-period, two-sequence, and crossover design, involving 23 healthy volunteers. One of the 0.25 mg formulations of pramipexole evaluated in the study was manufactured by PT Dexa Medica, Palembang, Indonesia, the other, used as the reference, by Boehringer Ingelheim Pharma GmbH & Co. KG, Ingelheim am Rhein, Germany. All eligible subjects were required to fast before each drug administration period, which was separated by a one-week washout period. Pramipexole concentrations in plasma were assayed using a validated ultra performance liquid chromatography with mass spectrometry (UPLC-MS/MS) detector. The evaluated pharmacokinetic parameters included the area under the plasma concentration curve from time zero to the last observed measurable concentration (AUC 0-t ), the area under the plasma concentration curve extrapolated to infinite time (AUC 0-∞ ), the maximum plasma concentration (C max ), the time to reach C max (t max ), and the plasma concentration half-life (t 1/2 ). To evaluate the bioequivalence of those two pramipexole formulations, 90% confidence intervals (CIs) for geometric mean ratios of both formulations were calculated for AUC and C max parameters, while t max and t 1/2 differences were analyzed on the non-transformed data using Wilcoxon matched-pairs and a Student's paired t -test, respectively. The 90% CIs for the geometric mean ratios of the two pramipexole formulations were 95.89% (90.73%-101.34%), 95.53% (89.75%-101.68%), and 92.11% (84.35%-100.58%) for AUC 0-t , AUC 0-∞ , and C max , respectively. There were no statistically significant differences for t max and t 1/2 between the two pramipexole formulations. It is concluded that two pramipexole formulations in this study were bioequivalent.

  14. Extending Metformin Use in Diabetic Kidney Disease: A Pharmacokinetic Study in Stage 4 Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Ajith Munasinghe Dissanayake

    2017-07-01

    Discussion: In our patient cohorts with diabetes and stage 4 chronic kidney disease, treatment with 4 weeks of low-dose metformin was not associated with adverse safety outcomes and revealed stable pharmacokinetics. Our study supports the liberalization of metformin use in this population and supports the use of metformin assays for more individualized dosing.

  15. Observational infant exploratory [14C]-paracetamol pharmacokinetic microdose/therapeutic dose study with accelerator mass spectrometry bioanalysis

    NARCIS (Netherlands)

    Garner, C.R.; Park, K.B.; French, N.S.; Earnshaw, C.; Schipani, A.; Selby, A.M.; Byrne, L.; Siner, S.; Crawley, F.P.; Vaes, W.H.J.; Duijn, E. van; ligt, R. de; Varendi, H.; Lass, J.; Grynkiewicz, G.; Maruszak, W.; Turner, M.A.

    2015-01-01

    Aims The aims of the study were to compare [14C]-paracetamol ([14C]-PARA) paediatric pharmacokinetics (PK) after administration mixed in a therapeutic dose or an isolated microdose and to develop further and validate accelerator mass spectrometry (AMS) bioanalysis in the 0-2 year old age group.

  16. Pharmacokinetics and antiviral activity of PHX1766, a novel HCV protease inhibitor, using an accelerated Phase I study design

    NARCIS (Netherlands)

    D.M. Hotho (Daphne); J. Bruijne (Joep); N. O'Farrell; T. Boyea (Teresa); J. Li (Jianke); M. Bracken (Michele); X. Li (Xin); D. Campbell (David); H.-P. Guler (Hans-Peter); C.J. Weegink (Christine); J. Schinkel (Janke); R. Molenkamp (Richard); J. Van De Wetering De Rooij (Jeroen); A.A. Vliet (Andre); H.L.A. Janssen (Harry); R.J. de Knegt (Robert); H.W. Reesink (Henk)

    2012-01-01

    textabstractBackground: PHX1766 is a novel HCV NS3/4 protease inhibitor with robust potency and high selectivity in replicon studies (50% maximal effective concentration 8 nM). Two clinical trials investigated the safety, tolerability, pharmacokinetics and antiviral activity of PHX1766 in healthy

  17. Efficacy of 2-Hydroxypropyl-β-cyclodextrin in Niemann-Pick Disease Type C Model Mice and Its Pharmacokinetic Analysis in a Patient with the Disease.

    Science.gov (United States)

    Tanaka, Yuta; Yamada, Yusei; Ishitsuka, Yoichi; Matsuo, Muneaki; Shiraishi, Koki; Wada, Koki; Uchio, Yushiro; Kondo, Yuki; Takeo, Toru; Nakagata, Naomi; Higashi, Taishi; Motoyama, Keiichi; Arima, Hidetoshi; Mochinaga, Sakiko; Higaki, Katsumi; Ohno, Kousaku; Irie, Tetsumi

    2015-01-01

    Niemann-Pick type C disease (NPC), an autosomal recessive lysosomal storage disorder, is an inherited disease characterized by the accumulation of intracellular unesterified cholesterol. A solubilizing agent of lipophilic compounds, 2-hydroxypropyl-β-cyclodextrin (HPBCD), is an attractive drug candidate against NPC disease. However, establishment of the optimum dosage of HPBCD remains to be determined. In this study, we evaluated the effective dosage of HPBCD in NPC model (Npc1(-/-)) mice, and determined serum HPBCD concentrations. Subcutaneous injection of 1000-4000 mg/kg HPBCD improved the lifespan of Npc1(-/-) mice. In addition, liver injury and cholesterol sequestration were significantly prevented by 4000 mg/kg HPBCD in Npc1(-/-) mice. Serum HPBCD concentrations, when treated at the effective dosages (1000-4000 mg/kg), were approximately 1200-2500 µg/mL at 0.5 h after subcutaneous injection, and blood HPBCD concentrations were immediately eliminated in Npc1(-/-) mice. Furthermore, we examined serum HPBCD concentrations when treated at 40000 mg (approximately 2500 mg/kg) in a patient with NPC. We observed that the effective concentration in the in vivo study using Npc1(-/-) mice was similar to that in the patient. In the patient, systemic clearance and the volume of distribution of HPBCD were in accordance with the glomerular filtration rate and extracellular fluid volume, respectively. These results could provide useful information for developing the optimal dosage regimen for HPBCD therapy when administered intravenously to NPC patients.

  18. Pharmacokinetic and bioequivalence studies of immediate release diclofenac potassium tablets (50mg) in healthy volunteers.

    Science.gov (United States)

    Ali, Huma; Shoaib, Muhammad Harris; Zafar, Farya; Hanif, Muhammad; Bushra, Rabia; Naz, Asia; Khursheed, Raheela

    2016-09-01

    This study was conducted with the aim to determine the pharmacokinetic and bioequivalence of diclofenac potassium 50 mg test (F4) tablet formulation with reference product (Caflam). Present study was single dose, randomized, two phase cross over design, conducted in 12 healthy Pakistani volunteers and planned in accordance with FDA guidelines. In this study a simple, selective, sensitive and reproducible HPLC procedure was developed and validated for the estimation of diclofenac potassium in plasma. The process was validated in the range of 50 - 0.05 µg.mL-1 and used in bioequivalence trial of two products. Multiple blood samples were collected at various time points (0.5, 1, 2, 3, 4, 5, 6, 8, 10, 12 and 14 hr after treating volunteers with test (F4) and marketed reference brand. Plasma separation and deproteination were carried out with acetonitrile; samples (20µL) were injected using the validated HPLC method. Various pharmacokinetic parameters (compartmental and noncompartmental) were estimated using KineticaTM 4.4.1 (Thermo Electron Corp. USA). Bioequivalence among the products was established by calculating the 90% CI with log and non log transformed data for Cmaxcalc, Tmaxcalc, AUC0-∞, AUCtot and AUClast using two way ANOVA and Schirmann's Two one sided t- test. No significant difference was found between log and non-log data. The 90% confidence interval values using log transformed data for AUC0-∞ (0.997-1.024), AUCtot (1.004-1.031), AUClast (0.997 -1.024), Cmaxcalc (0.994-1.007) and Tmaxcalc (0.996-1.013) for the trial and reference products were found within the FDA acceptable limits of 0.8-1.25. Results were further verified by the Schirmann's one-sided t test. Results showed the bioequivalence of test and reference formulations. Both the products were well tolerated.

  19. Determination of ifenprodil by LC–MS/MS and its application to a pharmacokinetic study in healthy Chinese volunteers

    Directory of Open Access Journals (Sweden)

    Jing Yang

    2013-05-01

    Full Text Available This paper reports the development and validation of an assay for ifenprodil based on liquid chromatography–tandem mass spectrometry (LC–MS/MS and its application to a pharmacokinetic study involving single and multiple intravenous infusions to healthy Chinese volunteers. After sample preparation of plasma by liquid–liquid extraction with ethyl acetate, the analyte and internal standard, urapidil, were separated by reversed phase chromatography in a run time of 4 min and detected by positive ion electrospray ionization followed by multiple reaction monitoring of the precursor-to-product ion transitions at m/z 326.2→308.1 for ifenprodil and m/z 388.4→205.3 for IS. The assay was linear in the concentration range 0.2–50.0 ng/mL with recovery >76.4%. In the pharmacokinetic study of single intravenous infusions of 5, 10 and 15 mg ifenprodil, peak plasma concentrations and areas under the plasma concentration–time curve were both linearly related to dose. In the pharmacokinetic study of multiple once daily intravenous infusions of 10 mg ifenprodil for 7 days, pharmacokinetic parameters were similar to those after the single dose showing that ifenprodil does not accumulate on repeated administration.

  20. A pharmacokinetic and bioequivalence study of Contiflo ICON 400 µg tablets in healthy Indian subjects.

    Science.gov (United States)

    Monif, T; Arora, V; Madan, S; Arora, R; Balaji, A; Jha, D; Thudi, N R

    2010-12-01

    Tamsulosin, an alpha1 adrenoceptor blocking agent, exhibits selectivity for alpha1 receptors in human prostate. Blockade of these adrenoceptors can cause smooth muscles in the bladder neck and prostate to relax, resulting in an improvement in urine flow rate and a reduction in symptoms of benign prostatic hypertrophy. A new formulation Contiflo ICON 400 µg has been developed by Ranbaxy Laboratories Limited, India similar to Flomaxtra XL 400 µg of Astellas Pharma Limited, United Kingdom. This product is specifically designed to achieve a more consistent plasma concentration over a period of 24-h, a lower maximum plasma concentration (Cmax) and an independence of pharmacokinetics (PKs) on food intake. The objective of the present study was to evaluate the pharmacokinetics and bioequivalence of the new formulation Contiflo ICON 400 µg of Ranbaxy Laboratories Limited, India and Flomaxtra XL 400 µg prolonged release tablets (containing tamsulosin hydrochloride prolonged release 400 µg) of Astellas Pharma Limited, United Kingdom. Study was conducted as an open label, balanced, randomized, two-treatment, two-period, two-sequence, cross over, single-dose bioequivalence study in 32 adult male human subjects under fed conditions. The mean (range) age, weight and height of the study subjects were 27.03 years (19 - 40 years), 57.19 kg (48 - 72 kg) and 166.81 cm (154 - 181 cm) respectively. Blood samples were collected at pre-dose and at 0.5, 1, 2, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 8, 9, 10, 12, 16, 20, 24, 36, 48, 72, and 96 h post dose in each period. Plasma samples were analyzed for tamsulosin by using validated liquid chromatographic mass spectrometry (LC-MS/MS) method. The Mean ± SD of pharmacokinetic parameters tmax, Cmax, AUC24, AUClast and AUCinf for Tamsulosin were 11.741 ± 4.7201 and 12.155 ± 6.3077 h, 10.7614 ± 4.76709 and 10.4954 ± 5.08979 ng/ml, 171.4674 ± 77.39695 and 160.6738 ± 77.98628 ng.h/ml, 262.7771 ± 150.21432 and 250.6854 ± 156.75581 ng

  1. Pharmacological evaluation and preliminary pharmacokinetics studies of a new diclofenac prodrug without gastric ulceration effect.

    Science.gov (United States)

    Santos, Jean Leandro Dos; Moreira, Vanessa; Campos, Michel Leandro; Chelucci, Rafael Consolin; Barbieri, Karina Pereira; de Castro Souto, Pollyana Cristina Maggio; Matsubara, Márcio Hideki; Teixeira, Catarina; Bosquesi, Priscila Longhin; Peccinini, Rosângela Gonçalves; Chin, Chung Man

    2012-11-19

    Long-term nonsteroidal anti-inflammatory drugs (NSAIDs) therapy has been associated with several adverse effects such as gastric ulceration and cardiovascular events. Among the molecular modifications strategies, the prodrug approach is a useful tool to discover new safe NSAIDs. The 1-(2,6-dichlorophenyl)indolin-2-one is a diclofenac prodrug which demonstrated relevant anti-inflammatory properties without gastro ulceration effect. In addition, the prodrug decreases PGE(2) levels, COX-2 expression and cellular influx into peritoneal cavity induced by carrageenan treatment. Preliminary pharmacokinetic studies have shown in vivo bioconversion of prodrug to diclofenac. This prodrug is a new nonulcerogenic NSAID useful to treat inflammatory events by long-term therapy.

  2. Pharmacological Evaluation and Preliminary Pharmacokinetics Studies of a New Diclofenac Prodrug without Gastric Ulceration Effect

    Directory of Open Access Journals (Sweden)

    Chung Man Chin

    2012-11-01

    Full Text Available Long-term nonsteroidal anti-inflammatory drugs (NSAIDs therapy has been associated with several adverse effects such as gastric ulceration and cardiovascular events. Among the molecular modifications strategies, the prodrug approach is a useful tool to discover new safe NSAIDs. The 1-(2,6-dichlorophenylindolin-2-one is a diclofenac prodrug which demonstrated relevant anti-inflammatory properties without gastro ulceration effect. In addition, the prodrug decreases PGE2 levels, COX-2 expression and cellular influx into peritoneal cavity induced by carrageenan treatment. Preliminary pharmacokinetic studies have shown in vivo bioconversion of prodrug to diclofenac. This prodrug is a new nonulcerogenic NSAID useful to treat inflammatory events by long-term therapy.

  3. Phase I safety, tolerability and pharmacokinetic study of recombinant human mannan-binding lectin

    DEFF Research Database (Denmark)

    Petersen, K.A.; Matthiesen, F.; Agger, T.

    2006-01-01

    (rhMBL) is in development as a novel therapeutic approach. To assess the safety, tolerability, and pharmacokinetics of rhMBL, a placebo-controlled double-blinded study was performed in MBL-deficient healthy male subjects. rhMBL was administered as both single intravenous (i.v.) infusions (0.01, 0...... mild and no serious adverse events were recorded. There were no clinically significant changes in laboratory evaluations, ECG or vital signs, and no anti-MBL antibodies were detected following rhMBL administration. After single i.v. doses of rhMBL the maximal plasma levels increased in a dose...... of the complement system without non-specific activation of the complement cascade.In conclusion, no safety or tolerability concern was raised following rhMBL administration no signs of immunogenicity detected, and an rhMBL plasma level judged sufficient to achieve therapeutic benefit (>1000 ng/mL) can be achieved....

  4. Comparative pharmacokinetics and biodistribution studies of {sup 99m}Tc-annexin V produced by different radiolabeling methods

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Josefina da Silva; Pujatti, Priscilla Brunelli; Couto, Renata Martinussi; Mengatti, Jair; Araujo, Elaine Bortoleti de, E-mail: jssantos@usp.b, E-mail: priscillapujatti@yahoo.com.b, E-mail: renatamartinussicouto@yahoo.com.b, E-mail: jmengatti@ipen.b, E-mail: ebaraujo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    The use of radiolabeled annexin A5 (ANXA5) to detect cell death in vivo has increased in the last years. Several {sup 99m}Tc-labeling techniques were reported using different cores, such as [{sup 99m}Tc=O]{sup +3}, [{sup 99m}Tc]HYNIC, [{sup 99m}Tcident toN]{sup +2} and [Tc(CO{sub 3})]{sup +1}. The goal of the present work was to evaluate the influence of {sup 99m}Tc cores in the biological behavior of radiolabeled ANXA5 in Swiss mice using [{sup 99m}Tc=O]{sup +3}, [{sup 99m}Tc]HYNIC cores. Ethylenedicysteine (EC) was applied to obtain [Tc=O]{sup +3} core, N,N,N',N'-tetramethyl(succinimide) uranium tetrafluoroborate (TSTU) was employed to transfer the carboxyl group to their corresponding hydroxysuccinimide ester and HYNIC-ANXA5 was provided by National Cancer Institute-Frederick. ITLC-SG and HPLC analysis were applied to determine non-desirable products and the stability of preparations was evaluated after incubation at room temperature, 4 deg C and in human serum at 37 deg C. In vivo biodistribution and kinetics studies were performed after the intravenous injection of {sup 99m}Tc-HYNIC-ANXA5 and {sup 99m}Tc-EC-ANXA5 and pharmacokinetic parameters were calculated using Biexp software. ANXA5 was radiolabeled at room temperature with high yield (> 95%). The results of biodistribution in mice showed, as expected, higher renal uptake of {sup 99m}Tc-HYNICANXA5 and higher liver uptake of {sup 99m}Tc-EC-ANXA5. The percent injected activity per gram (% IA/g) in liver at 0.5 hours were 6.52 and 1.09 and in kidneys were 1.59 and 32.2 for {sup 99m}Tc-EC-ANXA5 and {sup 99m}Tc-HYNICANXA5, respectively. The results of radioactivity in blood showed that both HYNIC- and EC- radiolabeled ANXA5 presented fast blood clearance. In this study two {sup 99m}Tc-ANXA5 obtained from three different available radiolabeling methods presently were investigated. Each labeling method possesses unique advantages and disadvantages. (author)

  5. Comparative pharmacokinetics and biodistribution studies of 99mTc-annexin V produced by different radiolabeling methods

    International Nuclear Information System (INIS)

    Santos, Josefina da Silva; Pujatti, Priscilla Brunelli; Couto, Renata Martinussi; Mengatti, Jair; Araujo, Elaine Bortoleti de

    2009-01-01

    The use of radiolabeled annexin A5 (ANXA5) to detect cell death in vivo has increased in the last years. Several 99m Tc-labeling techniques were reported using different cores, such as [ 99m Tc=O] +3 , [ 99m Tc]HYNIC, [ 99m Tc≡N] +2 and [Tc(CO 3 )] +1 . The goal of the present work was to evaluate the influence of 99m Tc cores in the biological behavior of radiolabeled ANXA5 in Swiss mice using [ 99m Tc=O] +3 , [ 99m Tc]HYNIC cores. Ethylenedicysteine (EC) was applied to obtain [Tc=O] +3 core, N,N,N',N'-tetramethyl(succinimide) uranium tetrafluoroborate (TSTU) was employed to transfer the carboxyl group to their corresponding hydroxysuccinimide ester and HYNIC-ANXA5 was provided by National Cancer Institute-Frederick. ITLC-SG and HPLC analysis were applied to determine non-desirable products and the stability of preparations was evaluated after incubation at room temperature, 4 deg C and in human serum at 37 deg C. In vivo biodistribution and kinetics studies were performed after the intravenous injection of 99m Tc-HYNIC-ANXA5 and 99m Tc-EC-ANXA5 and pharmacokinetic parameters were calculated using Biexp software. ANXA5 was radiolabeled at room temperature with high yield (> 95%). The results of biodistribution in mice showed, as expected, higher renal uptake of 99m Tc-HYNICANXA5 and higher liver uptake of 99m Tc-EC-ANXA5. The percent injected activity per gram (% IA/g) in liver at 0.5 hours were 6.52 and 1.09 and in kidneys were 1.59 and 32.2 for 99m Tc-EC-ANXA5 and 99m Tc-HYNICANXA5, respectively. The results of radioactivity in blood showed that both HYNIC- and EC- radiolabeled ANXA5 presented fast blood clearance. In this study two 99m Tc-ANXA5 obtained from three different available radiolabeling methods presently were investigated. Each labeling method possesses unique advantages and disadvantages. (author)

  6. Enzyme-inducing anticonvulsants increase plasma clearance of dexmedetomidine: a pharmacokinetic and pharmacodynamic study.

    Science.gov (United States)

    Flexman, Alana M; Wong, Harvey; Riggs, K Wayne; Shih, Tina; Garcia, Paul A; Vacas, Susana; Talke, Pekka O

    2014-05-01

    Dexmedetomidine is useful during mapping of epileptic foci as it facilitates electrocorticography unlike most other anesthetic agents. Patients with seizure disorders taking enzyme-inducing anticonvulsants appear to be resistant to its sedative effects. The objective of the study was to compare the pharmacokinetic and pharmacodynamic profile of dexmedetomidine in healthy volunteers with volunteers with seizure disorders receiving enzyme-inducing anticonvulsant medications. Dexmedetomidine was administered using a step-wise, computer-controlled infusion to healthy volunteers (n = 8) and volunteers with seizure disorders (n = 8) taking phenytoin or carbamazapine. Sedation and dexmedetomidine plasma levels were assessed at baseline, during the infusion steps, and after discontinuation of the infusion. Sedation was assessed by using the Observer's Assessment of Alertness/Sedation Scale, Ramsay Sedation Scale, and Visual Analog Scale and processed electroencephalography (entropy) monitoring. Pharmacokinetic analysis was performed on both groups, and differences between groups were determined using the standard two-stage approach. A two-compartment model was fit to dexmedetomidine concentration-time data. Dexmedetomidine plasma clearance was 43% higher in the seizure group compared with the control group (42.7 vs. 29.9 l/h; P = 0.007). In contrast, distributional clearance and the volume of distribution of the central and peripheral compartments were similar between the groups. No difference in sedation was detected between the two groups during a controlled range of target plasma concentrations. This study demonstrates that subjects with seizure disorders taking enzyme-inducing anticonvulsant medications have an increased plasma clearance of dexmedetomidine as compared with healthy control subjects.

  7. Oral fondaparinux: use of lipid nanocapsules as nanocarriers and in vivo pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Ramadan A

    2011-11-01

    Full Text Available Alyaa Ramadan1,4, Frederic Lagarce1,3, Anne Tessier-Marteau2, Olivier Thomas1, Pierre Legras5, Laurent Macchi2, Patrick Saulnier1, Jean Pierre Benoit1,31LUNAM Université, Ingénierie de la Vectorisation Particulaire, Inserm U-646, Angers, France; 2Hematology Department, Angers University Hospital, Angers, France; 3Department of Pharmacy, Angers University Hospital, Angers, France; 4Department of Pharmaceutics, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; 5SCAHU, Animal House, Angers, FranceAbstract: Oral anticoagulant therapy could be advanced using lipid-based nanoparticulate systems. This study examined lipid nanocapsules for their oral absorption potential as the first step in developing oral fondaparinux (Fp novel carriers. Using phase inversion method and cationic surfactants such as hexadecyltrimethyl ammonium bromide (CTAB or stearylamine (SA, cationic lipid nanocapsules (cLNCs, loaded with Fp on their surface, were prepared and characterized (zeta potential, size and Fp association efficiency and content. In vivo studies were conducted after single oral increasing doses of Fp-loaded cLNCs (0.5 to 5 mg/kg of Fp in rats and the concentration of Fp in the plasma was measured by anti-factor Xa activity assay. The monodisperse, (~50 nm, positively charged Fp-cLNCs with high drug loadings demonstrated linear pharmacokinetic profiles of the drug with an increased oral absolute bioavailability (up to ~21% compatible with therapeutic anticoagulant effect (>0.2 µg/mL.Keywords: oral anticoagulant, fondaparinux, lipid nanocapsules, bioavailability, pharmacokinetics, rats

  8. Effect of fluoxetine on the pharmacokinetics of lansoprazole: a two-treatment period study in healthy male subjects.

    Science.gov (United States)

    Vlase, Laurian; Popa, Adina; Neag, Maria; Muntean, Dana; Leucuta, Sorin E

    2011-10-01

    Fluoxetine is an inhibitor of the main metabolizing enzymes of lansoprazole and could influence the pharmacokinetics of lansoprazole. The changes in lansoprazole pharmacokinetics could have clinical significance concerning the safety of the therapy. The aim of this study was to evaluate the pharmacokinetic interaction between fluoxetine and lansoprazole in healthy subjects. A dose of lansoprazole 30 mg, alone or in combination with fluoxetine 60 mg, was administered to 18 healthy male subjects in a two-treatment study design, separated by an 8-day period in which fluoxetine alone was administered as a single oral daily dose. Plasma concentrations of lansoprazole were determined during a 12-hour period following drug administration. Lansoprazole plasma concentrations were determined by a validated liquid chromatography-mass spectrometry method. The pharmacokinetic parameters of lansoprazole were calculated using non-compartmental analysis. In the two periods of treatment, the mean maximum plasma concentration (C(max)) values were 817 ng/mL (lansoprazole alone) and 1370 ng/mL (lansoprazole in combination with fluoxetine after pre-treatment with fluoxetine for 8 days) [p lansoprazole and suggest that the observed interaction may be clinically significant, although its clinical relevance has yet to be confirmed.

  9. Psychomotor effect differences between l-methamphetamine and d-methamphetamine are independent of murine plasma and brain pharmacokinetics profiles

    OpenAIRE

    Nishimura, Tetsuya; Takahata, Kazue; Kosugi, Yuri; Tanabe, Takaaki; Muraoka, Shizuko

    2017-01-01

    l-Methamphetamine has been occasionally referred to as a stimulant similar to d-methamphetamine, probably owing to insufficient comparative studies. Here, we directly compared psychomotor efficacies and pharmacokinetics of methamphetamine enantiomers in mice. Only d-methamphetamine, but not l-methamphetamine, induced stereotypy and sensitization at 1?10?mg/kg. However, plasma pharmacokinetic parameters of 10?mg/kg l-methamphetamine were ?tenfold those of 1?mg/kg d-methamphetamine. These resul...

  10. Two-dose-level confirmatory study of the pharmacokinetics and tolerability of everolimus in Chinese patients with advanced solid tumors

    Directory of Open Access Journals (Sweden)

    Jappe Annette

    2011-01-01

    Full Text Available Abstract Background This phase I, randomized, multicenter, open-label study investigated the pharmacokinetics, safety, and efficacy of the oral mammalian target of rapamycin inhibitor everolimus in Chinese patients with advanced solid tumors. Methods A total of 24 patients with advanced breast cancer (n = 6, gastric cancer (n = 6, non-small cell lung cancer (n = 6, or renal cell carcinoma (n = 6 who were refractory to/unsuitable for standard therapy were randomized 1:1 to oral everolimus 5 or 10 mg/day. Primary end points were pharmacokinetic parameters and safety and tolerability. Pharmacokinetic 24-h profiles were measured on day 15; trough level was measured on days 2, 8, 15, 16, and 22. Tolerability was assessed continuously. This final analysis was performed after all patients had received 6 months of study drug or had discontinued. Results Everolimus was absorbed rapidly; median Tmax was 3 h (range, 1-4 and 2 h (range, 0.9-6 in the 5 and 10 mg/day groups, respectively. Pharmacokinetic parameters increased dose proportionally from the 5 and 10 mg/day doses. Steady-state levels were achieved by day 8 or earlier. The most common adverse events suspected to be related to everolimus therapy were increased blood glucose (16.7% and 41.7% and fatigue (16.7% and 33.3% in the everolimus 5 and 10 mg/day dose cohorts, respectively. Best tumor response was stable disease in 10 (83% and 6 (50% patients in the 5 and 10 mg/day groups, respectively. Conclusions Everolimus 5 or 10 mg/day was well tolerated in Chinese patients with advanced solid tumors. The observed safety and pharmacokinetic profile of everolimus from this study were consistent with previous studies. Trial registration Chinese Health Authorities 2008L09346

  11. Pharmacokinetic studies of the recombinant chicken interferon-α in broiler chickens.

    Science.gov (United States)

    Zhao, Jun; Yu, Hai-Yang; Zhang, Jun-Ling; Wang, Xing-Man; Li, Jin-Pei; Hu, Tao; Hu, Yong; Wang, Ming-Li; Shen, Yong-Zhou; Xu, Jing-Dong; Han, Guo-Xiang; Chen, Jason

    2017-02-14

    In this study, 24 male and female broiler chickens at 30-day-old were divided into three groups with 8 animals in each group. The animals were administered with recombinant chicken interferon-α (rChIFN-α) at a dose of 1.0 × 10 6 IU/kg intravenously, intramuscularly or subcutaneously, respectively. Serum samples were collected at different time points post administration, and the titers of rChIFN-α in the blood were determined by cytopathic effect inhibition assay. The results showed that the pharmacokinetic characteristics of rChIFN-α by intramuscular injection and subcutaneous injection were fitted to one compartment open model, and the T max was 3.21 ± 0.79 hr and 3.95 ± 0.85 hr, respectively, and the elimination half-life (T 1/2 ) was 6.20 ± 2.77 hr and 5.03 ± 3.70 hr, respectively. In contrast, the pharmacokinetics of rChIFN-α via intravenous injection was in line with the open model of two-compartment and was eliminated in the first order, and the elimination half-life (T 1/2 ) was 4.61 ± 0.84 hr. In addition, compared with those in the intravenous group and the subcutaneous group, the bioavailability of rChIFN-α in the intramuscular group was 82.80%. In conclusion, rChIFN-α was rapidly absorbed and slowly eliminated after intramuscular administration of single dose of rChIFN-α aqueous formulations. Thus, rChIFN-α can be used as a commonly-used therapeutic agent.

  12. Pharmacokinetic-Pharmacodynamic Modeling to Study the Antipyretic Effect of Qingkailing Injection on Pyrexia Model Rats

    Directory of Open Access Journals (Sweden)

    Zhixin Zhang

    2016-03-01

    Full Text Available Qingkailing injection (QKLI is a modern Chinese medicine preparation derived from a well-known classical formulation, An-Gong-Niu-Huang Wan. Although the clinical efficacy of QKLI has been well defined, its severe adverse drug reactions (ADRs were extensively increased. Through thorough attempts to reduce ADR rates, it was realized that the effect-based rational use plays the key role in clinical practices. Hence, the pharmacokinetic-pharmacodynamic (PK-PD model was introduced in the present study, aiming to link the pharmacokinetic profiles with the therapeutic outcomes of QKLI, and subsequently to provide valuable guidelines for the rational use of QKLI in clinical settings. The PK properties of the six dominant ingredients in QKLI were compared between the normal treated group (NTG and the pyrexia model group (MTG. Rectal temperatures were measured in parallel with blood sampling for NTG, MTG, model control group (MCG, and normal control group (NCG. Baicalin and geniposide exhibited appropriate PK parameters, and were selected as the PK markers to map the antipyretic effect of QKLI. Then, a PK-PD model was constructed upon the bacalin and geniposide plasma concentrations vs. the rectal temperature variation values, by a two-compartment PK model with a Sigmoid Emax PD model to explain the time delay between the drug plasma concentration of PK markers and the antipyretic effect after a single dose administration of QKLI. The findings obtained would provide fundamental information to propose a more reasonable dosage regimen and improve the level of individualized drug therapy in clinical settings.

  13. Pharmacokinetic study of flunixin and its interaction with enrofloxacin after intramuscular administration in calves

    Directory of Open Access Journals (Sweden)

    K. Abo-EL-Sooud

    Full Text Available The Pharmacokinetic aspects of flunixin (FL administered alone and in combination with enrofloxacin (EN, were studied in clinically healthy calves. The experiments were performed on two groups: FL alone {2.2 mg/kg,intramuscular (IM}, and combination of FL (2.2 mg/kg, IM and EN {2.5 mg/kg, IM}. Plasma concentrations of FL were determined using High Performance Liquid Chromatography (HPLC method. Moreover, the effects of FL alone or in combination on liver and kidney functions were also assessed. Flunixin was rapidly absorbed intramuscularly with a half-life of absorption (t of 0.094 h and the peak plasma concentration (C was 1.27 g/mL was attained after 1/2ab max 0.49 h (T . Enrofloxacin significantly altered the pharmacokinetics of FL by delaying its absorption and accelerate its max elimination from body. Significant increases (32% in the area under the curve (AUC and (37% in the elimination rate constant (K from the central compartment and a significant decrease (27% in the elimination half-life (t of FL el 1/2el were found following coadministration with EN, compared with administration of FL alone. The maximum plasma drug concentration (C showed significant increase (28% following the coadministration of EN with FL as max compared to that following the administration of FL alone. It was concluded that the combination of FL and EN negatively altered the kinetics of FL and exaggerated the adverse effect on hepato-renal function in calves consequently; the concomitant use of FL and EN should be avoided in calves. [Vet. World 2011; 4(10.000: 449-454

  14. Pharmacokinetics and tolerance study of intravitreal injection of dexamethasone-loaded nanoparticles in rabbits

    Directory of Open Access Journals (Sweden)

    Linhua Zhang

    2009-09-01

    Full Text Available Linhua Zhang1, Yue Li2, Chao Zhang1, Yusheng Wang2, Cunxian Song11Institute of Biomedical Engineering, Peking Union Medical College and Chinese Academy of Medical Sciences, Tianjin, China; 2Department of Ophthalmology, Institute of Ophthalmology of Chinese PLA, Xijing Hospital, Fourth Military Medical University, Xi’an, ChinaAbstract: The aim of the study was to investigate the tolerance and pharmacokinetics of dexamethasone (DEX-loaded poly(lactic acid–co-glycolic acid nanoparticles (DEX-NPs in rabbits after intravitreal injection. The DEX-NPs were prepared and characterized in terms of morphology, particle size and size distribution, encapsulation efficiency, and in vitro release. Ophthalmic investigations were performed, including fundus observation and photography, intraocular pressure measurement, and B-scan ocular ultrasonography. There were no abnormalities up to 50 days after administration of DEX-NPs in rabbits. The DEX concentrations in plasma and the ocular tissues such as the cornea, aqueous humor, lens, iris, vitreous humor, and chorioretina were determined by high-pressure liquid chromatography. The DEX-NPs maintained a sustained release of DEX for about 50 days in vitreous and provided relatively constant DEX levels for more than 30 days with a mean concentration of 3.85 mg/L-1. Based on the areas under the curve, the bioavailability of DEX in the experimental group was significantly higher than that in the control group injected with regular DEX. These results suggest that intravitreal injection of DEX-NPs lead to a sustained release of DEX with a high bioavailability, providing a basis for a novel approach to the treatment of posterior segment diseases.Keywords: dexamethasone, nanoparticles, intravitreal injection, pharmacokinetics

  15. A QSAR, Pharmacokinetic and Toxicological Study of New Artemisinin Compounds with Anticancer Activity

    Directory of Open Access Journals (Sweden)

    Josinete B. Vieira

    2014-07-01

    Full Text Available The Density Functional Theory (DFT method and the 6-31G** basis set were employed to calculate the molecular properties of artemisinin and 20 derivatives with different degrees of cytotoxicity against the human hepatocellular carcinoma HepG2 line. Principal component analysis (PCA and hierarchical cluster analysis (HCA were employed to select the most important descriptors related to anticancer activity. The significant molecular descriptors related to the compounds with anticancer activity were the ALOGPS_log, Mor29m, IC5 and GAP energy. The Pearson correlation between activity and most important descriptors were used for the regression partial least squares (PLS and principal component regression (PCR models built. The regression PLS and PCR were very close, with variation between PLS and PCR of R2 = ±0.0106, R2ajust = ±0.0125, s = ±0.0234, F(4,11 = ±12.7802, Q2 = ±0.0088, SEV = ±0.0132, PRESS = ±0.4808 and SPRESS = ±0.0057. These models were used to predict the anticancer activity of eight new artemisinin compounds (test set with unknown activity, and for these new compounds were predicted pharmacokinetic properties: human intestinal absorption (HIA, cellular permeability (PCaCO2, cell permeability Maden Darby Canine Kidney (PMDCK, skin permeability (PSkin, plasma protein binding (PPB and penetration of the blood-brain barrier (CBrain/Blood, and toxicological: mutagenicity and carcinogenicity. The test set showed for two new artemisinin compounds satisfactory results for anticancer activity and pharmacokinetic and toxicological properties. Consequently, further studies need be done to evaluate the different proposals as well as their actions, toxicity, and potential use for treatment of cancers.

  16. Pharmacokinetic and bioequivalence study of two brands of valsartan tablets in healthy male volunteers.

    Science.gov (United States)

    Zakeri-Milani, Parvin; Valizadeh, Hadi; Islambulchilar, Ziba; Nemati, Mahboob

    2010-01-01

    Valsartan (CAS 137862-53-4) is an antihypertensive drug belonging to the family of angiotensin II receptor antagonists acting at the AT1 receptor, which mediates all known effects of angiotensin II on the cardiovascular system. In the present study, the pharmacokinetic parameters of two oral formulations of valsartan tablets were compared in a randomized, single oral dose, two-treatment crossover design in 24 healthy male volunteers under fasting conditions. After an overnight fast, the volunteers received 80 mg valsartan. Blood samples were collected up to 48 h and drug concentrations were determined by a reverse-phase HPLC method with fluorescence detection. Various pharmacokinetic parameters were determined from the plasma concentration-time curves of both formulations. The obtained values for test and reference products were 3067.7 +/- 1,281.7 and 3,304.3 +/- 1,196.4 ng/ml for Cmax; 17,834.4 +/- 7,083.8 and 18,319.1 +/- 7,800.7 ng x h/ml for AUC0-48; 18,825.7 +/- 7,553.2 and 19,172.2 +/- 8,307.2 ng x h/ml for AUC0-infinity, respectively. The 90% confidence intervals obtained by analysis of variance were 86.84-100.87% for Cmax and 93.43-115.54% for AUC0-t, which are within the acceptance range of 80-125%. Therefore it can be concluded that both products are bioequivalent in terms of rate and extent of drug absorption and therefore interchangeable.

  17. Can we use mice to study schizophrenia?

    Science.gov (United States)

    Canetta, Sarah; Kellendonk, Christoph

    2018-03-19

    The validity of rodent models for the study of psychiatric disorders is controversial. Despite great efforts from academic institutions and pharmaceutical companies, as of today, no major therapeutic intervention has been developed for the treatment of psychiatric disorders based on mechanistic insights from rodent models. Here, we argue that despite these historical shortcomings, rodent studies are nevertheless instrumental for identifying neuronal circuit mechanisms underlying behaviours that are affected in psychiatric disorders. Focusing on schizophrenia, we will give four examples of rodent models that were generated based on genetic and environmental risk factors or pathophysiological evidence as entry points. We will then discuss how circuit analysis in these specific examples can be used for testing hypotheses about neuronal mechanisms underlying symptoms of schizophrenia, which will then guide the development of new therapies.This article is part of a discussion meeting issue 'Of mice and mental health: facilitating dialogue between basic and clinical neuroscientists'. © 2018 The Author(s).

  18. Influence of Renal Impairment on the Pharmacokinetics of Afatinib: An Open-Label, Single-Dose Study.

    Science.gov (United States)

    Wiebe, Sabrina; Schnell, David; Külzer, Raimund; Gansser, Dietmar; Weber, Anne; Wallenstein, Gudrun; Halabi, Atef; Conrad, Anja; Wind, Sven

    2017-06-01

    Afatinib is an oral irreversible ErbB-Family Blocker indicated for treatment of patients with EGFR mutation positive advanced non-small cell lung cancer. This trial assessed whether renal impairment influences the pharmacokinetics and safety of afatinib. This was an open-label, single-dose study. Pharmacokinetic parameters after afatinib 40 mg were investigated in subjects with moderate (n = 8) or severe (n = 8) renal impairment (estimated glomerular filtration rate 30-59 mL/min/1.73 m 2 and 15-29 mL/min/1.73 m 2 , respectively) and healthy matched controls (n = 14). Plasma and urine samples were collected before and up to 14 days after dosing for pharmacokinetic and plasma protein-binding assessment. Primary endpoints were area under the plasma concentration-time curve from time zero to the last quantifiable concentration (AUC last ) and maximum plasma concentration (C max ) between subjects with renal impairment and healthy matched controls. Pharmacokinetic profiles and plasma protein binding were similar in all groups. The extent of exposure, as indicated by AUC last and C max , was generally similar between the matched treatment groups, with the exception of the geometric mean ratio of AUC last for subjects with severe renal impairment, which showed a trend towards a higher value compared with matched healthy subjects (150.0 % [90 % CI 105.3-213.7]) Inter-individual variability was moderate (geometric mean coefficient of variation 28-39 % for moderate impairment, 34-42 % for severe impairment). Afatinib was well tolerated and urinary excretion was minimal. Moderate-to-severe renal impairment had a minor influence on the pharmacokinetics of afatinib that was within the observed inter-individual variability, suggesting that afatinib treatment can be considered in this patient population. Registered at ClinicalTrials.gov as NCT02096718.

  19. Pharmacokinetics of trefoil peptides and their stability in gastrointestinal contents

    DEFF Research Database (Denmark)

    Kjellev, Stine; Vestergaard, Else Marie; Nexø, Ebba

    2007-01-01

    Trefoil factor family (TFF) peptides are considered promising for therapeutic use in gastrointestinal diseases, and there is a need to explore the fate of injected TFF and the stability of the peptides in the gastrointestinal tract. We studied the pharmacokinetics of intravenously (i.v.) administ......Trefoil factor family (TFF) peptides are considered promising for therapeutic use in gastrointestinal diseases, and there is a need to explore the fate of injected TFF and the stability of the peptides in the gastrointestinal tract. We studied the pharmacokinetics of intravenously (i.......v.) administered hTFF2 in mice and rats and of hTFF3 administered i.v., intramuscularly, intraperitoneally, and subcutaneously in mice, and estimated by ELISA the decay of the peptides added to rat and human gastrointestinal contents. We found that i.v. injected hTFF2 and hTFF3 were cleared from the circulation...

  20. E-cigarette Nicotine Delivery: Data and Learnings from Pharmacokinetic Studies.

    Science.gov (United States)

    Fearon, Ian M; Eldridge, Alison; Gale, Nathan; Shepperd, Christopher J; McEwan, Mike; Camacho, Oscar M; Nides, Mitch; McAdam, Kevin; Proctor, Christopher J

    2017-01-01

    E-cigarettes could potentially play a major role in tobacco harm reduction by delivering nicotine in a vapor containing significantly fewer toxicants than cigarette smoke and may aid smoking behavior changes such as reduction or cessation. We examined blood nicotine levels in smokers who were non-accustomed to e-cigarette use (Study 1) and accustomed e-cigarette users (Study 2). We compared nicotine levels when participants used a closed modular system e-cigarette to those when participants smoked a cigarette. In Study 1, Cmax (geometric mean (CV)) during a 5-minute puffing period (10 puffs, 30 seconds apart) was 13.4 (51.4) ng/ ml for a regular cigarette. The e-cigarette Cmax was significantly lower (p .05) at 2.5 (67.8) ng/ml. In Study 2, during a 5-minute ad libitum puffing period, cigarette Cmax was 7.2 (130.8) ng/mL, and it was 7.8 (108.2) ng/mL for the e-cigarette. Our data demonstrate heterogeneity of nicotine deliveries both between products and also with the same products used by different cohorts, eg, accustomed users versus smokers. Such differences must be taken into account when determining the likely behavioral impact, on smoking reduction and cessation, of nicotine delivery data and when planning e-cigarette nicotine pharmacokinetic studies.

  1. Solid lipid nanoparticles as promising tool for intraocular tobramycin delivery: Pharmacokinetic studies on rabbits.

    Science.gov (United States)

    Chetoni, Patrizia; Burgalassi, Susi; Monti, Daniela; Tampucci, Silvia; Tullio, Vivian; Cuffini, Anna Maria; Muntoni, Elisabetta; Spagnolo, Rita; Zara, Gian Paolo; Cavalli, Roberta

    2016-12-01

    Eye drops are widely accepted as formulations for targeting the anterior segment notwithstanding their limitations in terms of bioavailability. The unique structure of the eye requires specially-designed formulations able to favor the pharmacokinetic profile of administered drugs, mainly minimizing the influence of ocular barriers. Nanotechnology-based delivery systems lead to significant technological and therapeutical advantages in ophthalmic therapy. The aim of the present study was to determine whether tobramycin as ion-pair incorporated in mucoadhesive Solid Lipid Nanoparticles (SLN) reaches the inner parts of the eye favoring drug activity. After technological characterization of the tobramycin entrapped SLN formulation (Tobra-SLN), a pharmacokinetic study in rabbits after topical instillation and intravenous administration of the formulation has been carried out. In addition, the intracellular activity of Tobra-SLN formulation against phagocytosed Pseudomonas aeruginosa was investigated. The SLN were spherical in shape, and showed a hydrodynamic diameter of about 80nm, a negative zeta potential (-25.7mV) with a polydispersity index of 0.15, representative of a colloidal dispersion with high quality, characterized by an unimodal relatively narrow size distribution. As demonstrated by FTIR and DSC, tobramycin ion-pair could be concentrated into lipid inner core of SLN, without interaction with the stearic acid, thus promoting a slow and constant drug release profile in the dissolution medium. Surprisingly, the drug concentration was significantly higher in all ocular tissues after ocular and intravenous administration of Tobra-SLN formulation with respect to reference formulations and only Tobra-SLN allowed the penetration of drug into retina. Furthermore, the use of Tobra-SLN resulted in both higher intraphagocytic antibiotic concentrations in polymorphonuclear granulocytes and greater bactericidal activity against intracellular Pseudomonas aeruginosa

  2. Pharmacokinetics and -dynamics of intramuscular and intranasal naloxone: an explorative study in healthy volunteers.

    Science.gov (United States)

    Skulberg, Arne Kristian; Tylleskar, Ida; Nilsen, Turid; Skarra, Sissel; Salvesen, Øyvind; Sand, Trond; Loftsson, Thorsteinn; Dale, Ola

    2018-03-22

    This study aimed to develop a model for pharmacodynamic and pharmacokinetic studies of naloxone antagonism under steady-state opioid agonism and to compare a high-concentration/low-volume intranasal naloxone formulation 8 mg/ml to intramuscular 0.8 mg. Two-way crossover in 12 healthy volunteers receiving naloxone while receiving remifentanil by a target-controlled infusion for 102 min. The group were subdivided into three different doses of remifentanil. Blood samples for serum naloxone concentrations, pupillometry and heat pain threshold were measured. The relative bioavailability of intranasal to intramuscular naloxone was 0.75. Pupillometry showed difference in antagonism; the effect was significant in the data set as a whole (p < 0.001) and in all three subgroups (p < 0.02-p < 0.001). Heat pain threshold showed no statistical difference. A target-controlled infusion of remifentanil provides good conditions for studying the pharmacodynamics of naloxone, and pupillometry was a better modality than heat pain threshold. Intranasal naloxone 0.8 mg is inferior for a similar dose intramuscular. Our design may help to bridge the gap between studies in healthy volunteers and the patient population in need of naloxone for opioid overdose. clinicaltrials.gov : NCT02307721.

  3. Is infant exposure to antiretroviral drugs during breastfeeding quantitatively important? A systematic review and meta-analysis of pharmacokinetic studies

    Science.gov (United States)

    Waitt, Catriona John; Garner, Paul; Bonnett, Laura Jayne; Khoo, Saye Hock; Else, Laura Jayne

    2015-01-01

    Objectives The objectives of this study were to summarize antiretroviral drug concentrations in breast milk (BM) and exposure of breast-fed infants. Methods This was a systematic review of pharmacokinetic studies of HIV-positive women taking antiretrovirals that measured drugs in BM. The quality of pharmacokinetic and laboratory methods was assessed using pre-defined criteria. Pooled ratios and 95% CIs were calculated using the generalized inverse variance method and heterogeneity was estimated by the I2 statistic. PubMed Central, SCOPUS and LactMed databases were searched. No date or language restrictions were applied. Searches were conducted up to 10 November 2014. Clinical relevance was estimated by comparing ingested dose with the recommended therapeutic dose for each drug. Results Twenty-four studies were included. There was substantial variability in the clinical and laboratory methods used and in reported results. Relative to maternal plasma (MP), NRTIs accumulate in BM, with BM : MP ratios (95% CI estimates) from 0.89 to 1.21 (14 studies, 1159 paired BM and MP samples). NNRTI estimates were from 0.71 to 0.94 (17 studies, 965 paired samples) and PI estimates were from 0.17 to 0.21 (8 studies, 477 paired samples). Relative to the recommended paediatric doses, a breast-fed infant may ingest 8.4% (95% CI 1.9–15.0), 12.5% (95% CI 2.6–22.3) and 1.1% (95% CI 0–3.6) of lamivudine, nevirapine and efavirenz, respectively, via BM. Conclusions Transfer to untreated infants appears quantitatively important for some NRTIs and NNRTIs. The pharmacokinetic methods varied widely and we propose standards for the design, analysis and reporting of future pharmacokinetic studies of drug transfer during breastfeeding. PMID:25858354

  4. Distribution and pharmacokinetics of the prodrug daunorubicin-GA3 in nude mice bearing human ovarian cancer xenografts

    NARCIS (Netherlands)

    Houba, PHJ; Boven, E; van der Meulen-Muileman, IH; Leenders, RGG; Scheeren, JW; Pinedo, HM; Haisma, HJ

    1999-01-01

    N-[4-daunorubicin-N-carbonyl (oxymethyl)phenyl] O-beta-glucuronyl carbamate (DNR-GA3) is a glucuronide prodrug of daunorubicin (DNR) which induced a better tumor growth delay than DNR when studied at equitoxic doses in three human ovarian cancer xenografts. These results suggested that the prodrug

  5. Sustained-release of caffeine from a polymeric tablet matrix: An in vitro and pharmacokinetic study

    International Nuclear Information System (INIS)

    Tan, Donna; Zhao Bin; Moochhala, Shabbir; Yang Yiyan

    2006-01-01

    Caffeine is utilized as a stimulant to impart a desired level of alertness during certain working hours. Usually, a single dose of caffeine induces 2-3 h of alertness coupled with side effects whereas a longer effect of 8-12 h is very useful for both daily life and military action. Thus, there is a need to deliver the stimulant continuously to an individual at one time to impart an increased level of alertness for the period stated after administration. This study aimed to design a polymeric microparticle system for sustained delivery of caffeine using a polymeric matrix. Poly(ethylene oxide) (PEO) was used as the erodible matrix material and the caffeine polymeric tablets were fabricated by compression using a Graseby Specac hydraulic press. In vitro release profiles as well as the pharmacokinetics studies data were obtained. Caffeine tablets fabricated using various polymers showed a high initial burst release type profile as compared to the caffeine-PEO-tablet. The PK studies showed sustained delivery of caffeine resulted in two expected phenomena: a reduction in the initial high rate of caffeine release (burst release) as well as a reduction in the change in caffeine concentration in the systemic circulation. A simple two-component system for sustained-release caffeine formulation therefore has been achieved

  6. Reconstructing exposures from biomarkers using exposure-pharmacokinetic modeling--A case study with carbaryl.

    Science.gov (United States)

    Brown, Kathleen; Phillips, Martin; Grulke, Christopher; Yoon, Miyoung; Young, Bruce; McDougall, Robin; Leonard, Jeremy; Lu, Jingtao; Lefew, William; Tan, Yu-Mei

    2015-12-01

    Sources of uncertainty involved in exposure reconstruction for short half-life chemicals were characterized using computational models that link external exposures to biomarkers. Using carbaryl as an example, an exposure model, the Cumulative and Aggregate Risk Evaluation System (CARES), was used to generate time-concentration profiles for 500 virtual individuals exposed to carbaryl. These exposure profiles were used as inputs into a physiologically based pharmacokinetic (PBPK) model to predict urinary biomarker concentrations. These matching dietary intake levels and biomarker concentrations were used to (1) compare three reverse dosimetry approaches based on their ability to predict the central tendency of the intake dose distribution; and (2) identify parameters necessary for a more accurate exposure reconstruction. This study illustrates the trade-offs between using non-iterative reverse dosimetry methods that are fast, less precise and iterative methods that are slow, more precise. This study also intimates the necessity of including urine flow rate and elapsed time between last dose and urine sampling as part of the biomarker sampling collection for better interpretation of urinary biomarker data of short biological half-life chemicals. Resolution of these critical data gaps can allow exposure reconstruction methods to better predict population-level intake doses from large biomonitoring studies. Published by Elsevier Inc.

  7. Preparation and analysis of deuterium-labeled aspirin: application to pharmacokinetic studies

    International Nuclear Information System (INIS)

    Pedersen, A.K.; FitzGerald, G.A.

    1985-01-01

    Inhibition of endogenous prostacyclin and thromboxane biosynthesis by aspirin is critically dose-dependent in humans. Gastrointestinal and hepatic hydrolysis may limit systemic availability of aspirin, especially in low doses, perhaps contributing to the biochemical selectivity of aspirin. Existing analytical methods do not permit determination of systemic bioavailability when low (less than 100 mg) doses of aspirin are administered. Deuterium-labeled aspirin (2-acetoxy[3,4,5,6- 2 H4]benzoic acid) was synthesized from salicylic acid by catalytic exchange and subsequent acetylation. Analysis of the compounds as benzyl esters by GC-MS followed extractive alkylation from plasma. Heptadeuterated compounds were used as internal standards. Simultaneous administration of tetradeuterated aspirin intravenously with native aspirin orally to anesthetized dogs permitted kinetic studies of both aspirin and salicylic acid. The sensitivity of the method is superior to published methods using HPLC and, thus, more applicable to studies of low dose aspirin. Pulse administration of stable isotope-labeled aspirin permits detailed and repeated studies of dose-related aspirin pharmacokinetics in humans

  8. Biphasic Elimination of Tenofovir Diphosphate and Nonlinear Pharmacokinetics of Zidovudine Triphosphate in a Microdosing Study

    Science.gov (United States)

    Chen, Jianmeng; Flexner, Charles; Liberman, Rosa G.; Skipper, Paul L.; Louissaint, Nicolette; Tannenbaum, Steven R.; Hendrix, Craig; Fuchs, Edward

    2012-01-01

    Objective Phase 0 studies can provide initial pharmacokinetics (PK) data in humans and help to facilitate early drug development, but their predictive value for standard dosing is controversial. To evaluate the prediction of microdosing for active intracellular drug metabolites, we compared the PK profile of two antiretroviral drugs, zidovudine (ZDV) and tenofovir (TFV), in microdose and standard dosing regimens. Study Design We administered a microdose (100 μg) of 14C-labeled drug (ZDV or tenofovir disoproxil fumarate (TDF)) with or without a standard unlabelled dose (300 mg) to healthy volunteers. Both the parent drug in plasma and the active metabolite, ZDV-triphosphate (ZDV-TP) or TFV-diphosphate (TFV-DP) in PBMCs and CD4+ cells were measured by AMS. Results The intracellular ZDV-TP concentration increased less than proportionally over the dose range studied (100 μg to 300 mg), while the intracellular TFV-DP PK were linear over the same dose range. ZDV-TP concentrations were lower in CD4+ cells versus total peripheral blood mononuclear cells (PBMCs), while TFV-DP concentrations were not different in CD4+ cells and PBMCs. Conclusion Our data were consistent with a rate-limiting step in the intracellular phosphorylation of ZDV but not TFV. AMS shows promise for predicting the PK of active intracellular metabolites of nucleosides, but nonlinearity of PK may be seen with some drugs. PMID:23187888

  9. Sustained-release of caffeine from a polymeric tablet matrix: An in vitro and pharmacokinetic study

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Donna [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117597 (Singapore); Zhao Bin [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117597 (Singapore); Moochhala, Shabbir [Defence Medical and Environmental Research Institute, DSO National Laboratories (Kent Ridge), 27 Medical Drive, 12-00, Singapore 117597 (Singapore)]. E-mail: mshabbir@dso.org.sg; Yang Yiyan [Institute of Bioengineering and Nanotechnology, 31 Biopolis Way, 04-01, The Nanos, Singapore 138669 (Singapore)

    2006-07-25

    Caffeine is utilized as a stimulant to impart a desired level of alertness during certain working hours. Usually, a single dose of caffeine induces 2-3 h of alertness coupled with side effects whereas a longer effect of 8-12 h is very useful for both daily life and military action. Thus, there is a need to deliver the stimulant continuously to an individual at one time to impart an increased level of alertness for the period stated after administration. This study aimed to design a polymeric microparticle system for sustained delivery of caffeine using a polymeric matrix. Poly(ethylene oxide) (PEO) was used as the erodible matrix material and the caffeine polymeric tablets were fabricated by compression using a Graseby Specac hydraulic press. In vitro release profiles as well as the pharmacokinetics studies data were obtained. Caffeine tablets fabricated using various polymers showed a high initial burst release type profile as compared to the caffeine-PEO-tablet. The PK studies showed sustained delivery of caffeine resulted in two expected phenomena: a reduction in the initial high rate of caffeine release (burst release) as well as a reduction in the change in caffeine concentration in the systemic circulation. A simple two-component system for sustained-release caffeine formulation therefore has been achieved.

  10. Pharmacokinetics and pharmacokinetic/pharmacodynamic associations of ofatumumab, a human monoclonal CD20 antibody, in patients with relapsed or refractory chronic lymphocytic leukaemia: a phase 1-2 study

    DEFF Research Database (Denmark)

    Coiffier, Bertrand; Losic, Nedjad; Rønn, Birgitte Biilmann

    2010-01-01

    The purpose of this phase 1-2 study was to investigate the association between the pharmacokinetic properties of ofatumumab, a human monoclonal CD20 antibody, and outcomes in 33 patients with relapsed/refractory chronic lymphocytic leukaemia receiving 4 weekly infusions of ofatumumab. The ofatumu...

  11. Quantitative determination of sirolimus in dog blood using liquid chromatography-tandem mass spectrometry, and its applications to pharmacokinetic studies.

    Science.gov (United States)

    Lee, Jong-Hwa; Cha, Kwang-Ho; Cho, Wonkyung; Park, Junsung; Park, Hee Jun; Cho, Youngseok; Hwang, Sung-Joo

    2010-12-01

    A rapid, sensitive method of detecting sirolimus in blood was developed and applied in pharmacokinetic studies employing deionized water for hemolysis and a weakly basic mobile phase to enhance chromatographic peak intensity. Dog blood samples were processed via liquid-liquid extraction and the amounts of sirolimus and tacrolimus, an internal standard, were quantified by LC-MS/MS. Specificity, the lower limit of quantification, linearity, accuracy, precision, dilution, recovery, matrix effects, robustness and stability were within the acceptable range for assay validation. The concentration of sirolimus was quantifiable in blood samples for up to 36 h after the dog had received a 3 mg/kg dose of sirolimus. These observations suggest that sirolimus can be detected at low levels in dog blood using a basic mobile phase and metal-free hemolysis. This method is therefore applicable to pharmacokinetic studies in dogs. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  12. Personal dosimetry calculations by means of radio pharmacokinetic and gamma graphic studies

    International Nuclear Information System (INIS)

    Arteaga de Murphy, C.; Ferro F, G.; Pedraza L, M.; Montoya M, C.E.

    2000-01-01

    The determination of the absorbed radiation dose is an essential factor to assess the risk to patient with a diagnostic study of nuclear medicine but over all it is indispensable for predicting the efficiency of individualized radio pharmacotherapy and weighting up the risk/benefit of the treatment. In studies for diagnostic or/and treatment of nuclear medicine generally the absorbed radiation dose is not determined for each patient since the methods for estimating it are laborious and include complex models such biological as mathematical, therefore is very important to have a relatively easy method. The obtained data with 99m Tc-Abp., a new radiopharmaceutical for osseous gammagraphy, were used with the purpose of exemplifying a practical method. The radio pharmacokinetic parameters were determined during 24 hours in 10 health voluntaries and serial gamma grams were taken during two hours to another voluntaries. The obtained data were used to estimate, with the MIRDOSE3 computer program, the absorbed radiation dose in an osseous dragging with 99m Tc-Abp. is low: 0.00472 m Gy/MBq to osseous marrow, mainly to the vertebral column and femur, and 0.00169 m Gy/ MBq to whole body. These data are lower than those informed in the medical literature for other bis phosphonates. (Author)

  13. Randomized pharmacokinetic study comparing subcutaneous and intravenous palonosetron in cancer patients treated with platinum based chemotherapy.

    Directory of Open Access Journals (Sweden)

    Belen Sadaba

    Full Text Available Palonosetron is a potent second generation 5- hydroxytryptamine-3 selective antagonist which can be administered by either intravenous (IV or oral routes, but subcutaneous (SC administration of palonosetron has never been studied, even though it could have useful clinical applications. In this study, we evaluate the bioavailability of SC palonosetron.Patients treated with platinum-based chemotherapy were randomized to receive SC or IV palonosetron, followed by the alternative route in a crossover manner, during the first two cycles of chemotherapy. Blood samples were collected at baseline and 10, 15, 30, 45, 60, 90 minutes and 2, 3, 4, 6, 8, 12 and 24 h after palonosetron administration. Urine was collected during 12 hours following palonosetron. We compared pharmacokinetic parameters including AUC0-24h, t1/2, and Cmax observed with each route of administration by analysis of variance (ANOVA.From October 2009 to July 2010, 25 evaluable patients were included. AUC0-24h for IV and SC palonosetron were respectively 14.1 and 12.7 ng × h/ml (p=0.160. Bioavalability of SC palonosetron was 118% (95% IC: 69-168. Cmax was lower with SC than with IV route and was reached 15 minutes following SC administration.Palonosetron bioavailability was similar when administered by either SC or IV route. This new route of administration might be specially useful for outpatient management of emesis and for administration of oral chemotherapy.ClinicalTrials.gov NCT01046240.

  14. Phase I Studies of Acebilustat: Pharmacokinetics, Pharmacodynamics, Food Effect, and CYP3A Induction.

    Science.gov (United States)

    Elborn, J S; Bhatt, L; Grosswald, R; Ahuja, S; Springman, E B

    2017-01-01

    Acebilustat is a new once-daily oral antiinflammatory drug in development for treatment of cystic fibrosis (CF) and other diseases. It is an inhibitor of leukotriene A4 hydrolase; therefore, production of leukotriene B4 (LTB4) in biological fluids provides a direct measure of the pharmacodynamic (PD) response to acebilustat treatment. Here we compare the pharmacokinetics (PK) and PD between CF patients and healthy volunteers, and investigate the food effect and CYP3A4 induction in healthy volunteers. No significant differences between study populations were observed for peak plasma level (C max ) or exposure (AUC). In healthy volunteers, a shift in time to C max (T max ) was observed after a high-fat meal, but there was no change in AUC. LTB4 production was reduced in the blood of both populations and in sputum from CF patients. Acebilustat did not induce CYP3A4. These results support continued clinical study of once-daily oral acebilustat in CF at doses of 50 and 100 mg. © 2016 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  15. An interlaboratory study of the pharmacokinetics of testosterone following intramuscular administration to Thoroughbred horses.

    Science.gov (United States)

    Moeller, B C; Sams, R A; Guinjab-Cagmat, J; Szabo, N J; Colahan, P; Stanley, S D

    2011-12-01

    Testosterone is an anabolic androgenic steroid (AAS) that is endogenously produced by both male and female horses that also has the potential for abuse when administered exogenously to race horses. To recommend appropriate withdrawal guidelines so that veterinarians can discontinue therapeutic use prior to competition, the pharmacokinetics and elimination of testosterone were investigated. An aqueous testosterone suspension was administered intramuscularly in the neck of Thoroughbred horses (n = 20). The disposition of testosterone from this formulation was characterized by an initial, rapid absorption phase followed by a much more variable secondary absorption phase. The median terminal half-life was 39 h. A second focus of this study was to compare the testosterone concentrations determined by two different laboratories using a percentage similarity model with a coefficient of variation of 16.5% showing good agreement between the two laboratories results. Based on the results of this study, a withdrawal period of 30 days for aqueous testosterone administered IM is recommended. © 2011 Blackwell Publishing Ltd.

  16. Accelerated Brain DCE-MRI Using Iterative Reconstruction With Total Generalized Variation Penalty for Quantitative Pharmacokinetic Analysis: A Feasibility Study.

    Science.gov (United States)

    Wang, Chunhao; Yin, Fang-Fang; Kirkpatrick, John P; Chang, Zheng

    2017-08-01

    To investigate the feasibility of using undersampled k-space data and an iterative image reconstruction method with total generalized variation penalty in the quantitative pharmacokinetic analysis for clinical brain dynamic contrast-enhanced magnetic resonance imaging. Eight brain dynamic contrast-enhanced magnetic resonance imaging scans were retrospectively studied. Two k-space sparse sampling strategies were designed to achieve a simulated image acquisition acceleration factor of 4. They are (1) a golden ratio-optimized 32-ray radial sampling profile and (2) a Cartesian-based random sampling profile with spatiotemporal-regularized sampling density constraints. The undersampled data were reconstructed to yield images using the investigated reconstruction technique. In quantitative pharmacokinetic analysis on a voxel-by-voxel basis, the rate constant K trans in the extended Tofts model and blood flow F B and blood volume V B from the 2-compartment exchange model were analyzed. Finally, the quantitative pharmacokinetic parameters calculated from the undersampled data were compared with the corresponding calculated values from the fully sampled data. To quantify each parameter's accuracy calculated using the undersampled data, error in volume mean, total relative error, and cross-correlation were calculated. The pharmacokinetic parameter maps generated from the undersampled data appeared comparable to the ones generated from the original full sampling data. Within the region of interest, most derived error in volume mean values in the region of interest was about 5% or lower, and the average error in volume mean of all parameter maps generated through either sampling strategy was about 3.54%. The average total relative error value of all parameter maps in region of interest was about 0.115, and the average cross-correlation of all parameter maps in region of interest was about 0.962. All investigated pharmacokinetic parameters had no significant differences between

  17. Validation and use of microdialysis for determination of pharmacokinetic properties of the chemotherapeutic agent mitomycin C - an experimental study

    International Nuclear Information System (INIS)

    Sørensen, Olaf; Andersen, Anders; Olsen, Harald; Alexandr, Kristian; Ekstrøm, Per Olaf; Giercksky, Karl-Erik; Flatmark, Kjersti

    2010-01-01

    Mitomycin C is a chemotherapeutic agent used in the treatment of peritoneal surface malignancies, administered as hyperthermic intraperitoneal chemotherapy after cytoreductive surgery. Pharmacokinetic studies have been based on analyses of blood, urine and abdominal perfusate, but actual tissue concentrations of the drug have never been determined. Microdialysis is an established method for continuous monitoring of low-molecular substances in tissues, and in the present study microdialysis of mitomycin C was studied in vitro and in vivo. Using in vitro microdialysis, relative recovery was determined when varying drug concentration, temperature and perfusion flow rate. In vivo microdialysis was performed in rats to verify long-term stability of relative recovery in four compartments (vein, peritoneum, extraperitoneal space and hind leg muscle). Subsequently, intravenous and intraperitoneal bolus infusion experiments were performed and pharmacokinetic parameters were calculated. In vitro, compatibility of mitomycin C and microdialysis equipment was demonstrated, and relative recovery was stable over an adequate concentration range, moderately increased by raising medium temperature and increased when flow rate was reduced, all according to theory. In vivo, stable relative recovery was observed over seven hours. Mitomycin C exhibited fast and even distribution in rat tissues, and equal bioavailability was achieved by intravenous and intraperitoneal infusion. The half-life of mitomycin C calculated after intravenous infusion was 40 minutes. Mitomycin C concentration can be reliable monitored in vivo using microdialysis, suggesting that this technique can be used in pharmacokinetic studies of this drug during hyperthermic intraperitoneal chemotherapy

  18. Replacing carbamazepine slow-release tablets with carbamazepine suppositories: a pharmacokinetic and clinical study in children with epilepsy.

    Science.gov (United States)

    Arvidsson, J; Nilsson, H L; Sandstedt, P; Steinwall, G; Tonnby, B; Flesch, G

    1995-03-01

    A suppository for rectal administration of carbamazepine has been developed for situations in which it is unsuitable to use the oral route of administration. In an open, controlled, within-patient study, the pharmacokinetics, clinical efficacy, and tolerability of carbamazepine slow-release tablets were compared with those of carbamazepine suppositories in children with epilepsy. The pharmacokinetic part of the study comprised 22 children, and an additional nine children were included in the clinical part of the study. Treatment with slow-release tablets was replaced for 7 days with carbamazepine suppositories in bioequivalent dosage. Clinical factors such as the rate of seizures and the local tolerability were studied, and an overall assessment of efficacy was made. In the pharmacokinetic part, 24-hour plasma concentration curves for carbamazepine and carbamazepine-10,11-epoxide were recorded. The plasma concentration profiles (minimum, maximum, and mean concentrations, fluctuation index, and area under the curve) for carbamazepine and the other metabolites did not show any significant differences between oral and rectal administration when the suppository dose was increased by 25% compared to the tablets. No increase in seizure frequency was detected, and the overall assessment was very good to good in 25 of the 29 epileptic children. Increased flatulence during treatment with suppositories was noted in two children, one had anal irritation, and one had nausea/vomiting. Treatment with carbamazepine slow-release tablets in children with epilepsy can be replaced by carbamazepine suppositories in 25% higher dosage, with good clinical effect and appropriate pharmacokinetic values, when it is unsuitable to use the common oral route of administration.

  19. Human plasma concentrations of tolbutamide and acetaminophen extrapolated from in vivo animal pharmacokinetics using in vitro human hepatic clearances and simple physiologically based pharmacokinetic modeling for radio-labeled microdose clinical studies

    International Nuclear Information System (INIS)

    Yamazaki, Hiroshi; Kunikane, Eriko; Nishiyama, Sayako; Murayama, Norie; Shimizu, Makiko; Sugiyama, Yuichi; Chiba, Koji; Ikeda, Toshihiko

    2015-01-01

    The aim of the current study was to extrapolate the pharmacokinetics of drug substances orally administered in humans from rat pharmacokinetic data using tolbutamide and acetaminophen as model compounds. Adjusted animal biomonitoring equivalents from rat studies based on reported plasma concentrations were scaled to human biomonitoring equivalents using known species allometric scaling factors. In this extrapolation, in vitro metabolic clearance data were obtained using liver preparations. Rates of tolbutamide elimination were roughly similar in rat and human liver microsome experiments, but acetaminophen elimination by rat liver microsomes and cytosolic preparations showed a tendency to be faster than those in humans. Using a simple physiologically based pharmacokinetic (PBPK) model, estimated human plasma concentrations of tolbutamide and acetaminophen were consistent with reported concentrations. Tolbutamide cleared in a roughly similar manner in humans and rats, but medical-dose levels of acetaminophen cleared (dependent on liver metabolism) more slowly from plasma in humans than it did in rats. The data presented here illustrate how pharmacokinetic data in combination with a simple PBPK model can be used to assist evaluations of the pharmacological/toxicological potential of new drug substances and for estimating human radiation exposures from radio-labeled drugs when planning human studies. (author)

  20. Meta-analysis of clinical studies supports the pharmacokinetic variability hypothesis for acquired drug resistance and failure of antituberculosis therapy.

    Science.gov (United States)

    Pasipanodya, Jotam G; Srivastava, Shashikant; Gumbo, Tawanda

    2012-07-01

    Using hollow-fiber tuberculosis studies, we recently demonstrated that nonadherence is not a significant factor for ADR and that therapy failure only occurs after a large proportion of doses are missed. Computer-aided clinical trial simulations have suggested that isoniazid and rifampin pharmacokinetic variability best explained poor outcomes. We were interested in determining whether isoniazid pharmacokinetic variability was associated with either microbiological failure or ADR in the clinic. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Prospective, randomized, controlled clinical trials that reported isoniazid acetylation status and microbiological outcomes were selected. The main effects examined were microbiological sputum conversion, ADR, and relapse. Effect size was expressed as pooled risk ratios (RRs) comparing rapid with slow acetylators. Thirteen randomized studies with 1631 rapid acetylators and 1751 slow acetylators met inclusion and exclusion criteria. Rapid acetylators were more likely than slow acetylators to have microbiological failure (RR, 2.0; 95% confidence interval [CI], 1.5-2.7), ADR (RR, 2.0; CI, 1.1-3.4), and relapse (RR, 1.3; CI, .9-2.0). Higher failure rates were encountered even in drug regimens comprising >3 antibiotics. No publication bias or small-study effects were observed for the outcomes evaluated. Pharmacokinetic variability to a single drug in the regimen is significantly associated with failure of therapy and ADR in patients. This suggests that individualized dosing for tuberculosis may be more effective than standardized dosing, which is prescribed in directly observed therapy programs.

  1. Cytotoxicity of hydroxydihydrobovolide and its pharmacokinetic studies in Portulaca oleracea L. extract

    Directory of Open Access Journals (Sweden)

    Liang Xu

    2017-06-01

    Full Text Available ABSTRACT Hydroxydihydrobovolide (HDB was for the first time isolated from Portulaca oleracea L. and then its cytotoxicity against SH-SYTY cells was studied. Moreover, a rapid and sensitive ultra-high performance liquid chromatographic (UHPLC method with bergapten as internal standard (IS was developed and validated to investigate the pharmacokinetics of HDB in rats after intravenous and oral administrations of extract (POE. The UHPLC analysis was performed on a Diamonsil C18 analytical column, using acetonitrile-water (35:65, v/v as the mobile phase with UV detection at 220 nm. The calibration curve was linear over the range of 0.2-25 µg/mL in rat plasma. The average extraction recovery was from 90.1 to 98.9%, and the relative standard deviations (RSDs of the intra- and inter-day precisions were less than 4.7 and 4.1%, respectively. The results showed that 50 µM HDB had significant cytotoxicity on the SH-SY5Y cells, which was rapidly distributed with a Tmax of 11 min after oral administration and presented a low absolute bioavailability, 4.12%.

  2. Distribution and chloramphenicol in the bovine genital tract and pharmacokinetic studies of florfenicol in cattle

    International Nuclear Information System (INIS)

    Bretzlaff, K.N.

    1986-01-01

    The objectives were to investigate selected aspects of the distribution of chloramphenicol (CAP) in the bovine genital tract and to conduct preliminary pharmacologic studies with florfenicol (FLO), a fluorinated analogue of thiamphenicol, in cattle. After 8 hours' continuous intravenous (IV) infusion of CAP to 7 postpartum cows, steady state plasma-to-genital tissue ratios of CAP were approximately 3. After intrauterine infusion of 20 mg CAP/kg to 3 postpartum cows, approximately 40% of the dose was absorbed into the bloodstream. Tissue concentrations were high at 8 hour postdosing in tissues lining the uterine lumen but were below desired therapeutic concentrations in the myometrium of 2 of the cows. Eighty cows with retained fetal membranes (RFM) were assigned to receive on the following treatments: (1) removal of membranes only; (2) removal plus CAP; (3) nonremoval; (4) nonremoval plus CAP. CAP treatment consisted of 5 g administered IU twice daily for 3 days. The majority of cows in all groups acquired endometritis, although CAP reduced the prevalence and severity of the disease. A quantitative assay for FLO in plasma was developed and validated on a high performance liquid chromatographic (HPLC) system. The pharmacokinetics of FLO determined after IV administration of 50 mg FLO/kg to 5 cows were best described by a three-compartment model. FLO was approximately 18% bound to plasma proteins as determined by equilibrium dialysis and ultrafiltration. In an in vitro system, 5, 125, or 1000 ug/ml of CAP had no effect on neutrophils from 6 cows

  3. Determination and pharmacokinetic studies of arecoline in dog plasma by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Li, Bing; Zhou, Xu-Zheng; Li, Jian-Yong; Yang, Ya-Jun; Niu, Jian-Rong; Wei, Xiao-Juan; Liu, Xi-Wang; Li, Jin-Shan; Zhang, Ji-Yu

    2014-10-15

    A rapid and sensitive high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of arecoline concentration in dog plasma. Plasma sample was prepared by protein precipitation using n-hexane (containing 1% isoamyl alcohol) with β-pinene as an internal standard. Chromatographic separation was achieved on an Agilent C18 column (4.6×75mm, 3.5μm) using methanol: 5mM ammonium acetate as the mobile phase with isocratic elution. Mass detection was carried out using positive electrospray ionization in multiple reaction monitoring mode. The calibration curve for arecoline was linear over a concentration range of 2-500ng/mL. The intra-day and inter-day accuracy and precision were within the acceptable limits of ±10% at all concentrations. In summary, the LC-MS/MS method described herein was fully validated and successfully applied to the pharmacokinetic study of arecoline hydrobromide tablets in dogs after oral administration. Copyright © 2014. Published by Elsevier B.V.

  4. Importance of pharmacokinetic studies in the management of acquired factor X deficiency.

    Science.gov (United States)

    Lim, Ming Y; McCarthy, Timothy; Chen, Sheh-Li; Rollins-Raval, Marian A; Ma, Alice D

    2016-01-01

    Up to 14% of individuals with systemic AL amyloidosis develop acquired factor X deficiency, which occurs due to adsorption of factor X onto amyloid fibrils. Although baseline factor X levels are not predictive of bleeding risk in these patients, serious hemorrhagic complications can occur, particularly during invasive procedures. Optimal management strategies to attenuate bleeding risk in these patients are unknown. We describe our experience in the management of acquired factor X deficiency, secondary to systemic AL amyloidosis, in a case series of three patients who received prothrombin complex concentrates (PCCs) for treatment and prevention of bleeding events. We performed a retrospective review extracting information on baseline demographics, laboratory data, pharmacokinetic (PK) studies, and clinically documented bleeding events. Our case series demonstrates that individuals with acquired factor X deficiency secondary to amyloidosis have variable laboratory and clinical responses to PCCs. This is likely due to distinct amyloid loads and fibril sequences, leading to different binding avidities for factor X. Our data emphasize the importance of performing PK testing prior to any invasive procedures to determine the dose and frequency interval to achieve adequate factor X levels for hemostasis, given the variable response between individuals. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Pharmacokinetics of Cefuroxime in Cortical and Cancellous Bone Obtained by Microdialysis - a Porcine Study

    DEFF Research Database (Denmark)

    Tøttrup, Mikkel; Forsingdal Hardlei, Tore; Bendtsen, Michael

    2014-01-01

    . As reference, free and total plasma concentrations were also measured. The animals received a bolus of 1500 mg cefuroxime over 30 min. No significant differences between key pharmacokinetic parameters for sealed and unsealed drill holes in cortical bone were found. The mean area under the concentration...... (MD) technique for measurement of cefuroxime in bone, and to obtain pharmacokinetic profiles for the same drug in porcine cortical and cancellous bone. Measurements were conducted in bone-wax sealed and unsealed drill holes in cortical bone, in drill holes in cancellous bone and in subcutaneous tissue...

  6. A pilot study on the serum pharmacokinetics of nattokinase in humans following a single, oral, daily dose.

    Science.gov (United States)

    Ero, Michael Penfield; Ng, Connie M; Mihailovski, Tamara; Harvey, Nathaniel R; Lewis, Brad Howard

    2013-01-01

    Nattokinase is a serine protease and is derived from natto, a traditional Japanese, fermented, soybean food meal. Multiple authors have described the significant fibrinolytic, antithrombotic, and antihypertensive effects of natto. Nattokinase has been growing in popularity for use as a dietary supplement for the benefit of cardiovascular health. Little is known regarding the pharmacokinetic and pharmacodynamic properties of this enzyme, and the bioavailability of nattokinase is currently unknown. This study intended to (1) detect nattokinase directly and immunologically, (2) show that nattokinase and/or its metabolites were detectable in human blood following ingestion of a commercial preparation, and (3) chart a pharmacokinetic dosing effect for nattokinase. The research team designed the pilot study as an in vivo, human clinical trial. Healthy human subjects responded to an advertisement and were screened. Subjects who satisfied both inclusion and exclusion criteria were enrolled into the study. Subjects were then instructed to orally ingest a single capsule containing a known concentration of nattokinase immediately following a baseline blood draw. Subsequent blood draws occurred over a 24-h period. This study was conducted in Oakland, California, at a clinical reference laboratory and was performed with the approval of an institutional review board (IRB) to ensure that appropriate ethical standards were met. Eleven healthy participants (five male, six female, ages 21-65), who met eligibility criteria, were enrolled. Administration of nattokinase occurred orally with the ingestion of a single daily dose (2000 FU) of nattokinase. Capsules, each containing approximately 100 mg of nattokinase, in softgel form (NSK-SD, Japan Bio Science Laboratory, Osaka, Japan), were used in the study. Baseline blood samples were collected, and participants were observed swallowing a single capsule of the nattokinase supplement before returning at 2, 4, 8, 12, 24, and 48 h post

  7. Pharmacokinetics of Active Components From Guhong Injection in Normal and Pathological Rat Models of Cerebral Ischemia: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Li Yu

    2018-05-01

    Full Text Available Background and Objectives: Guhong Injection (GHI is usually administered for the treatment of stroke in clinics. Aceglutamide and hydroxyl safflower yellow A (HSYA are its key ingredients for brain protective effect. To investigate the pharmacokinetics of aceglutamide and HSYA under pathological and normal conditions, the pharmacokinetic parameters and characteristics of middle cerebral artery occlusion (MCAO and normal rats given the same dosage of GHI were studied compared.Methods: 12 SD rats were divided into two groups, namely, MCAO and normal groups. Both groups were treated with GHI in the same dosage. Plasma samples were collected from the jaw vein at different time points and subsequently tested by high-performance liquid chromatography (HPLC.Results: After administration of GHI, both aceglutamide and HSYA were immediately detected in the plasma. Ninety percent of aceglutamide and HSYA was eliminated within 3 h. For aceglutamide, statistically significant differences in the parameters including AUC(0−t, AUC(0−∞, AUMC(0−t, AUMC(0−∞, Cmax (P < 0.01, and Vz (P < 0.05. Meanwhile, compared with the MCAO group, in the normal group, the values of AUC(0−t, AUMC(0−t, VRT(0−t, and Cmax (P < 0.01 for HSYA were significantly higher, whereas the value of MRT(0−t was significantly lower in the normal group.Conclusions: The in vivo trials based on the different models showed that, the pharmacokinetic behaviors and parameters of aceglutamide and HSYA in GHI were completely different. These results suggest that the pathological damage of ischemia-reperfusion has a significant impact on the pharmacokinetic traits of aceglutamide and HSYA.

  8. Clinical pharmacokinetic study for the effect of glimepiride matrix tablets developed by quality by design concept.

    Science.gov (United States)

    Ahmed, Tarek A; Suhail, Mohammad A A; Hosny, Khaled M; Abd-Allah, Fathy I

    2018-01-01

    Implementation of a new pharmaceutical technique to improve aqueous solubility and thus dissolution, enhancement of drug permeation, and finally formulation of a controlled release tablet loaded with glimepiride (GLMP). Improve GLMP bioavailability and pharmacokinetics in type II diabetic patients. Different polymers were used to enhance aqueous GLMP solubility of which a saturated polymeric drug solution was prepared and physically adsorbed onto silica. An experimental design was employed to optimize the formulation parameters affecting the preparation of GLMP matrix tablets. A compatibility study was conducted to study components interactions. Scanning electron microscope (SEM) was performed before and after the tablets were placed in the dissolution medium. An in vivo study in human volunteers was performed with the optimized GLMP tablets, which were compared to pure and marketed drug products. Enhancement of GLMP aqueous solubility, using the polymeric drug solution technique, by more than 6-7 times when compared with the binary system. All the studied formulation factors significantly affected the studied variables. No significant interaction was detected among components. SEM illustrated the surface and inner tablet structure, and confirmed the drug release which was attributed to diffusion mechanism. The volunteer group administered the optimized GLMP tablet exhibited higher drug plasma concentration (147.4 ng/mL), longer time to reach maximum plasma concentration (4 h) and longer t 1/2 (7.236 h) compared to other groups. Matrix tablet loaded with a physically modified drug form could represent a key solution for drugs with inconsistent dissolution and absorption profiles.

  9. Pharmacokinetics of surotomycin from phase 1 single and multiple ascending dose studies in healthy volunteers.

    Science.gov (United States)

    Chandorkar, Gurudatt; Zhan, Qiao; Donovan, Julie; Rege, Shruta; Patino, Hernando

    2017-03-28

    Surotomycin, a novel, orally administered, cyclic, lipopeptide antibacterial in development for the treatment of Clostridium difficile-associated diarrhea, has demonstrated minimal intestinal absorption in animal models. Safety, tolerability, and plasma pharmacokinetics of single and multiple ascending oral doses (SAD/MAD) of surotomycin in healthy volunteers were characterized in two randomized, double-blind, placebo-controlled, phase 1 studies. Participants were sequentially enrolled into one of four SAD (500, 1000, 2000, 4000 mg surotomycin) or three MAD (250, 500, 1000 mg surotomycin twice/day for 14 days) cohorts. Ten subjects were randomized 4:1 into each cohort to receive surotomycin or placebo. Surotomycin plasma concentrations rose as dose increased (maximum plasma concentration [C max ]: 10.5, 21.5, 66.6, and 86.7 ng/mL). Systemic levels were generally low, with peak median surotomycin plasma concentrations observed 6-12 h after the first dose. In the MAD study, surotomycin plasma concentrations were higher on day 14 (C max : 25.5, 37.6, and 93.5 ng/mL) than on day 1 (C max : 6.8, 11.0, and 21.1 ng/mL for increasing doses), indicating accumulation. In the SAD study, <0.01% of the administered dose was recovered in urine. Mean surotomycin stool concentration from the 1000 mg MAD cohort was 6394 μg/g on day 5. Both cohorts were well tolerated with all adverse events reported as mild to moderate. Both SAD and MAD studies of surotomycin demonstrated minimal systemic exposure, with feces the primary route of elimination following oral administration; consistent with observations with similar compounds, such as fidaxomicin. Results of these phase 1 studies support the continued clinical development of surotomycin for the treatment of Clostridium difficile-associated diarrhea. NCT02835118 and NCT02835105 . Retrospectively registered, July 13 2016.

  10. Optimal designs for population pharmacokinetic studies of oral artesunate in patients with uncomplicated falciparum malaria

    Directory of Open Access Journals (Sweden)

    Lindegardh Niklas

    2011-07-01

    Full Text Available Abstract Background Currently, population pharmacokinetic (PK studies of anti-malarial drugs are designed primarily by the logistical and ethical constraints of taking blood samples from patients, and the statistical models that are fitted to the data are not formally considered. This could lead to imprecise estimates of the target PK parameters, and/or designs insufficient to estimate all of the parameters. Optimal design methodology has been developed to determine blood sampling schedules that will yield precise parameter estimates within the practical constraints of sampling the study populations. In this work optimal design methods were used to determine sampling designs for typical future population PK studies of dihydroartemisinin, the principal biologically active metabolite of oral artesunate. Methods Optimal designs were derived using freely available software and were based on appropriate structural PK models from an analysis of data or the literature and key sampling constraints identified in a questionnaire sent to active malaria researchers (3-4 samples per patient, at least 15 minutes between samples. The derived optimal designs were then evaluated via simulation-estimation. Results The derived optimal sampling windows were 17 to 29 minutes, 30 to 57 minutes, 2.5 to 3.7 hours and 5.8 to 6.6 hours for non-pregnant adults; 16 to 29 minutes, 31 minutes to 1 hour, 2.0 to 3.4 hours and 5.5 to 6.6 hours for designs with non-pregnant adults and children and 35 to 59 minutes, 1.2 to 3.4 hours, 3.4 to 4.9 hours and 6.0 to 8.0 hours for pregnant women. The optimal designs resulted in acceptable precision of the PK parameters. Conclusions The proposed sampling designs in this paper are robust and efficient and should be considered in future PK studies of oral artesunate where only three or four blood samples can be collected.

  11. Treatment with subcutaneous and transdermal fentanyl: Results from a population pharmacokinetic study in cancer patients

    NARCIS (Netherlands)

    A.W. Oosten (Astrid); J.A. Abrantes (João A.); S. Jönsson (Siv); P. de Bruijn (Peter); E.J.M. Kuip (Evelien); A. Falcão (Amílcar); C.C.D. van der Rijt (Carin); A.H.J. Mathijssen (Ron)

    2016-01-01

    textabstractPurpose: Transdermal fentanyl is effective for the treatment of moderate to severe cancer-related pain but is unsuitable for fast titration. In this setting, continuous subcutaneous fentanyl may be used. As data on the pharmacokinetics of continuous subcutaneous fentanyl are lacking, we

  12. Pharmacokinetic Drug-Drug Interaction Study Between Raltegravir and Atorvastatin 20 mg in Healthy Volunteers

    NARCIS (Netherlands)

    Blonk, M.I.; Beek, M. van; Colbers, A.; Schouwenberg, B.J.; Burger, D.M.

    2015-01-01

    BACKGROUND: Dyslipidemia is highly prevalent among patients with HIV infection and contributes to an increased risk of cardiovascular disease. We investigated the influence of a frequently used statin, atorvastatin, on the pharmacokinetics of the HIV-integrase inhibitor raltegravir and vice versa.

  13. Pharmacokinetics of lidocaine and bupivacaine and stable isotope labelled analogues : a study in healthy volunteers

    NARCIS (Netherlands)

    Burm, A.G.D.; de Boer, A G; van Kleef, J.W.; Vermeulen, N P; de Leede, L G; Spierdijk, J; Breimer, D D

    1988-01-01

    The pharmacokinetics of lidocaine and bupivacaine and tri-deuteromethyl-labelled lidocaine and bupivacaine were investigated in healthy volunteers. The deuterium-labelled and the unlabelled form of the drug to be investigated were simultaneously infused in 10 min. Plasma concentrations were

  14. Pharmacokinetics of intravitreal 5-flurouracil prodrugs in silicone oil. Experimental studies in pigs

    DEFF Research Database (Denmark)

    Laugesen, Caroline S; Steffansen, Bente; Scherfig, Erik

    2005-01-01

    PURPOSE: To examine the in vivo pharmacokinetics of intravitreal 5-Fluorouracil (5-FU) following tamponade with 5-FU prodrug silicone oil formulations. METHOD: Two different alkoxycarbonyl 5-FU prodrugs denoted C12 and C18 were synthesized and formulated as silicone oil suspensions. A total of 26...

  15. Pharmacokinetic studies of bergapten in dog plasma by using a LC-MS/MS method studies.

    Science.gov (United States)

    Gao, Y; Liu, Y Z; Zhang, X-M; Zhou, Y; Zhang, X; Dong, C-Y

    2013-07-01

    A sensitive LC-MS/MS method was developed for the determination of bergapten in dog plasma. The chromatographic separation was carried out on a Hypersil ODS column with a mobile phase consisting of methanol-water. The plasma sample was precipitated with methanol and prepare for injecting onto the LC-MS/MS system. The detection was performed on a triple quadrupole tandem mass spectrometer by MRM via electro spray ionization source. The standard curve for bergapten was linear over the concentration range of 0.5-500 ng/mL with a lower limit of quantification of 0.5 ng/mL. The inter-day and intra-day precision (R.S.D.%) for bergapten varied between 3.4 and 11.5. The corresponding inter-day and intra-day accuracy (Bias%) ranged between -3.8 and 6.9. For the pharmacokinetic analysis of serum, the mean (SD) values obtained for the bergapten were as follows: Cmax, 228.5 (14.3) ng/ml; Tmax, 4.2 (0.4) h; t1/2, 6.9 (2.3) h; AUC0-t h, 2507.2 (168.5) ng · h/mL and AUC0-∞, 3 219.2 (211.4) ng · h/mL, respectively. © Georg Thieme Verlag KG Stuttgart · New York.

  16. An LC-MS/MS method for simultaneous determination of three Polygala saponin hydrolysates in rat plasma and its application to a pharmacokinetic study.

    Science.gov (United States)

    Wang, Qian; Xiao, Bing-Xin; Pan, Rui-Le; Liu, Xin-Min; Liao, Yong-Hong; Feng, Li; Cao, Fang-Rui; Chang, Qi

    2015-07-01

    Radix Polygala has a long history of use as a sedative in traditional Chinese medicine and its major ingredients are saponins, which are recognized effective in memory improvement but highly toxic to gastricintestinal mucosa. Polygala saponin hydrolysates (PSH), an alkaline hydrolysis product and also the intestinal metabolites of the saponins, exhibited stronger effects in improving memory of mice and had less toxicity than its original saponins. The present study aims to develop a sensitive LC-MS/MS method for simultaneously determining PSH three major active components, 3,4,5-trimethoxycinnamylic acid (TMCA), p-methoxycinnamylic acid (PMCA) and tenuifolin (TF), in rat plasma and apply the method to a pharmacokinetic study. The acidic plasma (100μl) was treated by liquid-liquid extraction with ethyl acetate and reconstituted sample was analyzed on a C18 column eluted with acetonitrile-water (50:50) containing 0.2% formic acid at 0.4ml/min. The mass detection in negative electrospray ionization was used. The ion pairs for multiple reaction monitoring were set at m/z 237.0/103.0, 177.0/116.6 and 679.5/425.3 for TMCA, PMCA and TF, respectively. Their pharmacokinetic profiles were studied in rats after intravenous and oral dose of PSH at 20 and 100mg/kg, respectively. The calibration curves had good linearity (r(2)>0.99) for TMCA, PMCA and TF within the tested concentration ranges. The limits of detection and quantification were 1, 10, 0.5ng/ml and 10.0, 20.0, 1.0ng/ml, respectively. The intra-day and inter-day precisions were less than 18.9% and accuracies between 93.2% and 113.3%, and the extraction recovery ranged from 91.2% to 112.1% for all analytes. The pharmacokinetic study showed that TMCA, PMCA and TF could be rapidly absorbed into the circulation and reached their peak concentrations at about 9.1, 9.0 and 24.0min, respectively. TF had a lower oral bioavailability (2.0%) than TMCA (90.1%) and PMCA (96.5%), but it remained in the body much longer (t1/2,

  17. Pharmacokinetics of Melatonin

    DEFF Research Database (Denmark)

    Andersen, Lars Peter Holst; Gögenur, Ismail; Rosenberg, Jacob

    2016-01-01

    Despite widespread clinical application of melatonin, several unanswered questions remain regarding the pharmacokinetics of this drug. This lack of knowledge may contribute to the inconsistency of results in previous clinical studies. Currently, a t max value of 30-45 min and a t ½elimination of ...

  18. A Pharmacokinetic Bioequivalence Study Comparing Pirfenidone Tablet and Capsule Dosage Forms in Healthy Adult Volunteers.

    Science.gov (United States)

    Pan, Lin; Belloni, Paula; Ding, Han Ting; Wang, Jianshuang; Rubino, Christopher M; Putnam, Wendy S

    2017-09-01

    Pirfenidone film-coated tablets were developed to offer an alternative to the marketed capsule formulation. This study assessed the bioequivalence of the tablet and capsule formulations under fed and fasted states. A Phase I, open-label, randomized, four-treatment-period, four-sequence, crossover pharmacokinetics study (NCT02525484) was conducted. Each subject received an 801-mg single dose of pirfenidone as three 267-mg capsules or one 801-mg tablet under fasted and fed conditions. Pirfenidone plasma C max , AUC 0-t and AUC 0-∞ were used to assess bioequivalence. Forty-four subjects were randomized to treatment. The 801-mg tablet in the fasted state met bioequivalence criteria [90% confidence intervals (CI) 80.00-125.00%] for the GLSM ratios of natural log-transformed C max , AUC 0-t and AUC 0-∞ . Under fed conditions, the 801-mg tablet met the bioequivalence criteria for AUC 0-t and AUC 0-∞ , but slightly exceeded the bioequivalence criteria for the C max (90% CI of 108.26-125.60%). The tablet C max was approximately 17% higher than that of the capsules. In the fed state, the tablet C max , and both AUC 0-t and AUC 0-∞ were reduced by 39% and 17%, respectively, relative to the fasted state. The tablet and capsules had acceptable tolerability profiles. The pirfenidone 801-mg tablet met bioequivalence criteria when compared with three 267-mg capsules in the fasted state. The tablet C max was slightly higher relative to capsules in the fed state, but this is not expected to have a clinically meaningful impact on the benefit-risk profile of pirfenidone. This work was supported by F. Hoffmann-La Roche Ltd.

  19. Development of a Pharmacokinetic Model to Describe the Complex Pharmacokinetics of Pazopanib in Cancer Patients

    NARCIS (Netherlands)

    Yu, Huixin; van Erp, Nielka; Bins, Sander; Mathijssen, Ron H J; Schellens, Jan H M; Beijnen, Jos H.; Steeghs, Neeltje; Huitema, Alwin D R

    Background and Objective: Pazopanib is a multi-targeted anticancer tyrosine kinase inhibitor. This study was conducted to develop a population pharmacokinetic (popPK) model describing the complex pharmacokinetics of pazopanib in cancer patients. Methods: Pharmacokinetic data were available from 96

  20. Development of a Pharmacokinetic Model to Describe the Complex Pharmacokinetics of Pazopanib in Cancer Patients

    NARCIS (Netherlands)

    Yu, H.; Erp, N. van; Bins, S.; Mathijssen, R.H.; Schellens, J.H.; Beijnen, J.H.; Steeghs, N.; Huitema, A.D.

    2017-01-01

    BACKGROUND AND OBJECTIVE: Pazopanib is a multi-targeted anticancer tyrosine kinase inhibitor. This study was conducted to develop a population pharmacokinetic (popPK) model describing the complex pharmacokinetics of pazopanib in cancer patients. METHODS: Pharmacokinetic data were available from 96

  1. [Pharmacokinetic and clinical studies on flomoxef in mature and premature infant].

    Science.gov (United States)

    Tomimasu, K; Tsuji, Y; Fukuda, M; Sakai, M; Nakashita, S; Uchida, T; Mori, G; Miyazoe, H; Motoyama, K

    1991-11-01

    Pharmacokinetic and clinical studies of flomoxef (FMOX) in neonates and premature infants were conducted, and the results obtained are summarized below. 1. Plasma concentrations of FMOX at 15 minutes after one shot intravenous injection of 20 mg/kg to 6 cases were in a rang of 33.0-69.9 micrograms/ml and half-lives (T 1/2's) were between 0.68 and 4.89 hours. The plasma concentration of FMOX at 15 minutes after one shot intravenous injection of 40 mg/kg to 1 case was 79.9 micrograms/ml and the half-life (T 1/2) was 2.45 hours. Drug concentrations in plasma upon 1-hour intravenous drip infusion were 71.1-114.0 micrograms/ml and T 1/2's were 1.64-3.41 hours. T 1/2 tended to be couse shorter as ages of babies increased. 2. Urinary excretion rates in the first 6 hours after one shot intravenous injection of FMOX 20 mg/kg to 1 case and 1-hour intravenous drip infusion of FMOX 40 mg/kg to 2 cases were 60.4%, and 27.2 and 55.3%, respectively. 3. Clinical effects of FMOX against 12 cases of bacterial infections were excellent in 6 cases, good in 5 cases and poor in 1 case, thus the clinical efficacy rate was 91.7%. FMOX was also given to 6 cases for prophylaxis and prophylactic effects were observed in all the cases. 4. No adverse effects were observed in the 21 cases examined, but elevations of S-GOT and S-GPT were found in 1 case. The abnormal laboratory test results were probably due to this drug.

  2. [Pharmacokinetic and clinical studies on flomoxef in the perinatal period in obstetrics and gynecology].

    Science.gov (United States)

    Yamamoto, T; Yasuda, J; Okada, H; Iwasaku, K

    1991-06-01

    Pharmacokinetic and clinical studies on flomoxef (FMOX) in the perinatal period in obstetrics and gynecology were performed and the results obtained are summarized as follows: 1. Concentrations of FMOX in maternal serum, umbilical cord serum and amniotic fluid were determined after intravenous injection of 1 g. The maternal serum concentration was 41.9 micrograms/ml at 16 minutes after administration, and gradually decreased thereafter to 1.36 micrograms/ml at 5 hours 19 minutes. The concentration of FMOX in umbilical cord serum was 17.5 micrograms/ml at 16 minutes after administration, then gradually decreased thereafter, was slightly higher than that in maternal serum after approx. 3 hours and was 2.88 micrograms/ml at 5 hours 19 minutes. The amniotic fluid concentration was 0.31 micrograms/ml at 16 minutes after administration, increased to 7.85-15.8 micrograms/ml at approx. 3 hours, and gradually decreased while maintaining relatively high levels. 2. One or two grams of FMOX were given by intravenous drip infusion twice daily to 17 patients with perinatal infections for 5 to 7 days. Clinical efficacies were evaluated as excellent in 7 cases and good in 10, suggesting that FMOX was effective in all cases. No subjective side effects were observed in any of the 17 patients. As to abnormal laboratory findings, a minor degree of elevation of GPT was observed in 1 patient and that of GOT.GPT in 1. No other abnormal changes in laboratory examinations were observed. Considering the above results, we conclude that FMOX is a useful antibiotic in perinatal infections.

  3. Distribution and chloramphenicol in the bovine genital tract and pharmacokinetic studies of florfenicol in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Bretzlaff, K.N.

    1986-01-01

    The objectives were to investigate selected aspects of the distribution of chloramphenicol (CAP) in the bovine genital tract and to conduct preliminary pharmacologic studies with florfenicol (FLO), a fluorinated analogue of thiamphenicol, in cattle. After 8 hours' continuous intravenous (IV) infusion of CAP to 7 postpartum cows, steady state plasma-to-genital tissue ratios of CAP were approximately 3. After intrauterine infusion of 20 mg CAP/kg to 3 postpartum cows, approximately 40% of the dose was absorbed into the bloodstream. Tissue concentrations were high at 8 hour postdosing in tissues lining the uterine lumen but were below desired therapeutic concentrations in the myometrium of 2 of the cows. Eighty cows with retained fetal membranes (RFM) were assigned to receive on the following treatments: (1) removal of membranes only; (2) removal plus CAP; (3) nonremoval; (4) nonremoval plus CAP. CAP treatment consisted of 5 g administered IU twice daily for 3 days. The majority of cows in all groups acquired endometritis, although CAP reduced the prevalence and severity of the disease. A quantitative assay for FLO in plasma was developed and validated on a high performance liquid chromatographic (HPLC) system. The pharmacokinetics of FLO determined after IV administration of 50 mg FLO/kg to 5 cows were best described by a three-compartment model. FLO was approximately 18% bound to plasma proteins as determined by equilibrium dialysis and ultrafiltration. In an in vitro system, 5, 125, or 1000 ug/ml of CAP had no effect on neutrophils from 6 cows.

  4. Pharmacokinetic interplay of phase II metabolism and transport: a theoretical study.

    Science.gov (United States)

    Wu, Baojian

    2012-01-01

    Understanding of the interdependence of cytochrome P450 enzymes and P-glycoprotein in disposition of drugs (also termed "transport-metabolism interplay") has been significantly advanced in recent years. However, whether such "interplay" exists between phase II metabolic enzymes and efflux transporters remains largely unknown. The objective of this article is to explore the role of efflux transporters (acting on the phase II metabolites) in disposition of the parent drug in Caco-2 cells, liver, and intestine via simulations utilizing a catenary model (for Caco-2 system) and physiologically based pharmacokinetic (PBPK) models (for the liver and intestine). In all three models, "transport-metabolism interplay" (i.e., inhibition of metabolite efflux decreases the metabolism) can be observed only when futile recycling (or deconjugation) occurred. Futile recycling appeared to bridge the two processes (i.e., metabolite formation and excretion) and enable the interplay thereof. Without futile recycling, metabolite formation was independent on its downstream process excretion, thus impact of metabolite excretion on its formation was impossible. Moreover, in liver PBPK model with futile recycling, impact of biliary metabolite excretion on the exposure of parent drug [(systemic (reservoir) area under the concentration-time curve (AUC(R1))] was limited; a complete inhibition of efflux resulted in AUC(R1) increases of less than 1-fold only. In intestine PBPK model with futile recycling, even though a complete inhibition of efflux could result in large elevations (e.g., 3.5-6.0-fold) in AUC(R1), an incomplete inhibition of efflux (e.g., with a residual activity of ≥ 20% metabolic clearance) saw negligible increases (interplay between phase II enzymes and efflux transporters. Those studying such "interplay" are encouraged to adequately consider potential consequences of inhibition of efflux transporters in humans. Copyright © 2011 Wiley-Liss, Inc.

  5. Radioprotectors and Tumors: Molecular Studies in Mice

    Energy Technology Data Exchange (ETDEWEB)

    Gayle Woloschak, David Grdina

    2010-03-10

    This proposal investigated effects of radiation using a set of archival tissues. Main interests of this proposal were to investigate effects of irradiation alone or in the presence or radioprotectors; to investigate these effects on different tissues; and to use/develop molecular biology techniques that would be suitable for work with archived tissues. This work resulted in several manuscripts published or in preparation. Approach for evaluation of gene copy numbers by quantitative real time PCR has been developed and we are striving to establish methods to utilize Q-RT-PCR data to evaluate genomic instability caused by irradiation(s) and accompanying treatments. References: 1. Paunesku D, Paunesku T, Wahl A, Kataoka Y, Murley J, Grdina DJ, Woloschak GE. Incidence of tissue toxicities in gamma ray and fission neutron-exposed mice treated with Amifostine. Int J Radiat Biol. 2008, 84(8):623-34. PMID: 18661379, http://informahealthcare.com/doi/full/10.1080/09553000802241762?cookieSet=1 2. Wang Q, Paunesku T and Woloschak GE. Tissue and data archives from irradiation experiments conducted at Argonne National Laboratory over a period of four decades, in press in Radiation and Environmental Biophysics. 3. Alcantara M, Paunesku D, Rademaker A, Paunesku T and Woloschak GE. A RETROSPECTIVE ANALYSIS OF TISSUE TOXICITIES IN B6CF1 MICE IRRADIATED WITH FISSION NEUTRONS OR COBALT 60 GAMMA RAYS: Gender modulates accumulation of tissue toxicities caused by low dose rate fractionated irradiation; in preparation; this document has been uploaded as STI product 4. Wang Q, Paunesku T Wanzer B and Woloschak GE. Mitochondrial gene copy number differences in different tissues of irradiated and control mice with lymphoid cancers; in preparation 5. Wang Q, Raha, S, Paunesku T and Woloschak GE. Evaluation of gene copy number differences in different tissues of irradiated and control mice; in preparation

  6. A pilot pharmacokinetic study of tricyclic antidepressant ovine Fab for TCA poisoning in children.

    Science.gov (United States)

    Yalindağ-Oztürk, Nilüfer; Goto, Collin S; Shepherd, Greene; Torres, Olivia Nayeli; Giroir, Brett

    2010-06-01

    A pilot study of tricyclic antidepressant (TCA)-specific antibody fragments (TCA Fab) in TCA-intoxicated adults showed a marked increase in serum total TCA concentrations following TCA Fab infusion with no worsening signs of TCA toxicity. TCA Fab pharmacokinetics (PK) was not described in this adult study. The objective of this study was to evaluate the PK of TCA Fab in children with TCA poisoning. This was an open-label, single-center, dose escalation pilot trial of three patients. Inclusion criteria were documented TCA ingestion with at least one serious complication (QRS prolongation, dysrhythmia, hypotension, seizure, or coma). Patients were assigned to either a low-dose intravenous TCA Fab regimen (15, 30, and 60 mg/kg) or a high-dose regimen (30, 60, and 120 mg/kg) as needed to reverse TCA toxicity. Following the administration of TCA Fab, samples of blood and urine were obtained for PK evaluations. The outcomes of interest were serum and urine TCA concentrations (free and total), serum and urine Fab concentrations, improvement or worsening of TCA toxicity, and adverse effects. Three study patients were 11, 11, and 14 years of age. Two patients received 15 mg/kg of TCA Fab and one patient received a total of 90 mg/kg of TCA Fab (30 + 60 mg/kg). Serum-bound TCA increased significantly following TCA Fab administration with concomitant enhanced urinary elimination. Serum-free TCA concentrations were minimal to undetectable. Fab data were available for two patients. The serum TCA Fab area under the curve was 306.12 mg/L/h for the 15 mg/kg dose and 2,198.10 mg/L/h for the 90 mg/kg dose of TCA Fab. Maximum Fab concentrations correlated with maximum bound TCA in serum. The volume of distribution (V(D)) of TCA Fab was 0.2-0.3 L/kg. The clearance was 0.036-0.05 L/kg/h and the elimination half-life was 4 h. No adverse effects were observed. The limited PK data from this study are consistent with binding of TCA to TCA Fab and redistribution of TCA from the tissue to

  7. Preclinical pharmacokinetics, interspecies scaling, and pharmacokinetics of a Phase I clinical trial of TTAC-0001, a fully human monoclonal antibody against vascular endothelial growth factor 2

    Directory of Open Access Journals (Sweden)

    Lee WS

    2018-03-01

    Full Text Available Weon Sup Lee,1 Sang Ryeol Shim,1 Seon Young Lee,1 Jin San Yoo,1 Sung Kweon Cho2 1PharmAbcine, Inc., Daejeon, Republic of Korea; 2Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, Republic of Korea Background: VEGF is a highly selective mitogen that serves as the central regulator of tumor angiogenesis by mediating endothelial proliferation, permeability, and survival. Tanibirumab (TTAC-0001 is a fully human IgG1 monoclonal antibody derived from a fully human naïve single-chain variable fragment (ScFv phage library that was developed to inhibit the effects of VEGF in the treatment of solid tumors, especially those of the brain. Methods: In the present study, we conducted intravenous pharmacokinetic studies of TTAC-0001 in mice, rats, and cynomolgus monkeys. At the doses studied (3 mg/kg, 10 mg/kg, 30 mg/kg, TTAC-0001 exhibited dose proportionality in mice and monkeys. At a dose of ~10 mg/kg, the clearance of TTAC-0001 from serum was 0.017 mL/h in mice, 0.35 mL/h in rats, and 2.19 mL/h in cynomolgus monkeys, and the terminal half-life ranged from 20–30 h among the three species. Pharmacokinetic data in mice, rats, and cynomolgus monkeys were used to predict the pharmacokinetics of TTAC-0001 in humans using allometric scaling. The predicted serum clearance of TTAC-0001 in humans was 102.45 mL/h and the terminal half-life was 27.52 h. Results: The maximum life span-corrected clearance value was 72.92 mL/h. The observed clearance in humans was more similar to the predicted scaled clearance. Conclusion: We investigated the pharmacokinetics of TTAC-0001 in mice, rats, and cynomolgus monkeys after intravenous administration. At the doses studied, TTAC-0001 exhibited dose proportionality in mice and monkeys. The scaled pharmacokinetics of TTAC-0001 reported here was useful for designing first-in-human studies. Allometric scaling in the therapeutic antibody is feasible. Keywords: VEGF2, tanibirumab, pharmacokinetics

  8. Preclinical studies on toxicity, antitumour activity and pharmacokinetics of cisplatin and three recently developed derivatives.

    Science.gov (United States)

    Lelieveld, P; Van der Vijgh, W J; Veldhuizen, R W; Van Velzen, D; Van Putten, L M; Atassi, G; Danguy, A

    1984-08-01

    Preclinical studies were performed in mice, rats and dogs of cis-diamminedichloroplatinum(II) (CDDP) and its derivatives cis-1,1-di(aminomethyl) cyclohexane platinum(II) sulphate (TNO-6), cis-diammine-1,1-cyclobutanedicarboxylate platinum(II) (CBDCA) and cis-dichloro, trans-dihydroxybis-isopropylamine platinum(IV) (CHIP). In mice toxicity and antitumour activity were determined. All three derivatives were at least as toxic as CDDP for haemopoietic stem cells and were less active than CDDP against the mouse tumours leukaemia L1210 and osteosarcoma C22LR. Toxicology studies in rats revealed no renal toxicity after a single dose of TNO-6. Fractionated doses of TNO-6 and CBDCA did cause renal toxicity but less than CDDP. CHIP produced little or no kidney damage. In dogs, TNO-6 (1.5 mg/kg) produced more severe kidney damage--although this was reversible--than CDDP (2 mg/kg). Half-lives of distribution were 4.0-5.1 min for TNO-6 and 9.7 min for CDDP, while half-lives of elimination were 3.6-6.6 days and 5.9 days respectively. Plasma levels, normalized for the dose, were at least two times higher after TNO-6 than after CDDP. Twelve weeks after drug administration, plasma levels were undetectable, while tissue concentrations could still be measured. The platinum concentration in kidney cortex was higher after CDDP than after TNO-6.

  9. Pharmacokinetics of a once-daily extended-release formulation of pramipexole in healthy male volunteers: three studies.

    Science.gov (United States)

    Jenner, Peter; Könen-Bergmann, Michael; Schepers, Cornelia; Haertter, Sebastian

    2009-11-01

    Pramipexole is a dopamine agonist used in the treatment of Parkinson's disease. The currently available immediate-release (IR) formulation is taken orally 3 times daily. These studies were conducted to evaluate the pharmacokinetic properties of a variety of prototypes for a once-daily extended-release (ER) formulation of pramipexole and to further characterize the prototype whose pharmacokinetics best matched those of the IR formulation. Three Phase I studies were conducted, all in healthy adult men aged food effect. In the third study, steady-state pharmacokinetics of the optimal ER formulation were assessed across a range of pramipexole doses (0.375-4.5 mg/d), including investigation of the food effect at steady state for the highest dose. Tolerability was assessed throughout all studies based on physical examinations, laboratory measurements, and adverse events (AEs). The 3 studies included 18, 15, and 39 subjects, respectively. Among the ER prototypes tested at 0.75 mg once daily in study 1, a matrix tablet had the optimal pharmacokinetic resemblance to IR pramipexole 0.25 mg TID, with a geometric mean AUC(0-24h,ss) of 17.4 ng.h/mL (vs 16.0 ng.h/mL for the IR formulation), C(max,ss) of 0.967 ng/mL (vs 1.09 ng/mL), and C(min,ss) of 0.455 ng/mL (vs 0.383 ng/mL). For single-dose ER 0.375 mg administered in the fasted state in study 2, in vivo bioavailability was predictable from in vitro dissolution data, with internal mean absolute percent prediction errors of 3.18% for AUC(0-30h) and 4.87% for C(max), and external mean absolute prediction errors of 6.61% and 3.34%, respectively, satisfying current guidelines for a level A IVIVC. For single-dose ER 0.375 mg administered in the fed state, the upper bound of the 90% CI for fed:fasted values was 119.8 for AUC(0-30h) (within the bioequivalence limits of 80%-125%) and 134.1 for C(max). At steady state in study 3 (subjects' 5th treatment day), dosing at 0.375 to 4.5 mg in the fasted state was associated with a linear

  10. Comparative study on the pharmacokinetics of inorganic and organic iron compounds in broiler chickens

    Directory of Open Access Journals (Sweden)

    Dimitrichka Dimitrova

    2014-03-01

    Full Text Available The pharmacokinetics of ferrous methionate and ferrous sulphate was investigated in broiler chickens after intravenous injection and crop intubation. The iron compounds were injected intravenously in v. brachialis. After 20-day “wash-out” period the ferrous methionate and ferrous sulphate were administered again by an elastic silicone tube into the crop. The serum concentrations of the iron were determined with bioanalyser. Two pharmacokinetic approaches were used – compartmental and non-compartmental analysis. After i.v. injection we found statistically significantly longer and better distribution of the iron contained in the ferrous methionate compared to the ferrous sulphate. The АUC0→∞ was statistically significantly higher in the ferrous methionate. In the alimentary tract of broiler chickens, ferrous methionate was absorbed more rapidly than ferrous sulfate. It was also distributed at a higher volume as compared to the ferrous sulfate.

  11. Pharmacokinetics of clomipramine during pregnancy

    NARCIS (Netherlands)

    Ter Horst, P G J; Proost, J H; Smit, J P; Vries, M T; de Jong-van den Berg, Lolkje; Wilffert, B

    2015-01-01

    Clomipramine is one of the drugs for depression during pregnancy; however, pharmacokinetic data of clomipramine and its active metabolite desmethylclomipramine in this vulnerable period are lacking. In this study, we describe clomipramine and desmethylclomipramine concentrations including their

  12. Polymeric films loaded with cisplatin for malignant pleural mesothelioma: a pharmacokinetic study in an ovine model

    Science.gov (United States)

    Barocelli, Elisabetta; Cavazzoni, Andrea; Petronini, Piergiorgio; Mucchino, Claudio; Cantoni, Anna Maria; Leonardi, Fabio; Ventura, Luigi; Barbieri, Stefano; Colombo, Paolo; Fusari, Antonella; Carbognani, Paolo; Rusca, Michele; Sonvico, Fabio

    2018-01-01

    Background Malignant pleural mesothelioma (MPM) continues to be a distressing tumor due to its aggressive biologic behavior and scanty prognosis. Several therapeutic approaches have been tested both in clinical and preclinical settings, being intrapleural chemotherapy one of the most promising. Some years ago, our interest focused on polymeric films loaded with cisplatin for the adjuvant intrapleural treatment of surgical patients. After in vitro and in vivo studies in a rat recurrence model of MPM, the aim of this study was to evaluate the pharmacokinetics of the polymeric films in a sheep model in view of further studies in a clinical setting. Methods An ovine model was used. Animals were divided into four groups according to pharmacologic treatment: control group (three animals undergoing left pneumonectomy and saline-NaCl solution); intrapleural hyaluronate cisplatin films (HYALCIS) group (six animals undergoing left pneumonectomy and intrapleural application of polymeric films loaded with cisplatin); intrapleural cisplatin solution (six animals undergoing left pneumonectomy and intrapleural application of cisplatin solution); intravenous cisplatin (five animals undergoing left pneumonectomy and intravenous administration of cisplatin solution). The primary objective was the plasmatic and pleural concentration of cisplatin in the treatment groups. The secondary objective was the treatment-related toxicity evaluated by plasmatic analysis performed at prearranged time intervals and histological examinations of tissue samples collected during animal autopsy. Analysis of variance (ANOVA) was used for statistical analysis. Bonferroni correction was applied for comparison between all groups. Results Twenty female Sardinian sheep with a mean weight of 45.1 kg were studied. All animals survived the surgical procedures. The whole surgical procedure had a mean duration of 113 minutes. Cisplatin blood levels obtained from polymeric films application were low during the

  13. Pharmacokinetic study and evaluation of the safety of taurolidine for dogs with osteosarcoma.

    Science.gov (United States)

    Marley, Kevin; Helfand, Stuart C; Simpson, Jennifer; Mata, John E; Tracewell, William G; Brownlee, Lisa; Bracha, Shay; Séguin, Bernard

    2013-10-11

    Osteosarcoma in dogs and humans share many similarities and the dog has been described as an excellent model to study this disease. The median survival in dogs has not improved in the last 25 years. Taurolidine has been shown to be cytotoxic to canine and human osteosarcoma in vitro. The goals of this study were to determine the pharmacokinetics and safety of taurolidine in healthy dogs and the safety of taurolidine in combination with doxorubicin or carboplatin in dogs with osteosarcoma. Two percent taurolidine was infused into six healthy dogs (150 mg/kg) over a period of two hours and blood samples were taken periodically. One dog received taurolidine with polyvinylpyrrolidone (PVP) as its carrier and later received PVP-free taurolidine as did all other dogs in this study. Serum taurolidine concentrations were determined using high-performance liquid chromatography (HPLC) online coupled to ESI-MS/MS in the multiple reaction monitoring mode. Subsequently, the same dose of taurolidine was infused to seven dogs with osteosarcoma also treated with doxorubicin or carboplatin. Taurolidine infusion was safe in 6 healthy dogs and there were no significant side effects. Maximum taurolidine serum concentrations ranged between 229 to 646 μM. The dog that received taurolidine with PVP had an immediate allergic reaction but recovered fully after the infusion was stopped. Three additional dogs with osteosarcoma received doxorubicin and taurolidine without PVP. Toxicities included dilated cardiomyopathy, protein-losing nephropathy, renal insufficiency and vasculopathy at the injection site. One dog was switched to carboplatin instead of doxorubicin and an additional 4 dogs with osteosarcoma received taurolidine-carboplatin combination. One incidence of ototoxicity occurred with the taurolidine- carboplatin combination. Bone marrow and gastro-intestinal toxicity did not appear increased with taurolidine over doxorubicin or carboplatin alone. Taurolidine did not

  14. Phase I biodistribution and pharmacokinetic study of Lewis Y targeting immunoconjugate CMD-193 in patients with advanced epithelial cancers

    International Nuclear Information System (INIS)

    Herbertson, R. A.; Lee, F. T.; Hopkins, W.; Smyth, F. E.; Murone, C.; Tebbutt, N. C.; Micallef, N.; MacFarlane, D. J.; Bellen, J.; Sonnichsen, D. S.; Brechbiel, M. W.; Scott, A. M.; Lee, T. L.

    2009-01-01

    Full text:Background: The Lewis Y (Ley) antigen is a blood-group related antigen expressed in >70% of solid tumours. This study explored the biodistribution and pharmacokinetics of the immunoconjugate CMD-193 (humanized anti-Ley antibody conjugated with calichaemicin) in patients with advanced Ley expressing epithelial cancers. Methods: There were 2 dose cohorts, (1.0mg/m2 and 2.6mg/m2). Primary objectives were to determine biodistribution and pharmacokinetics of CMD-193. The first cycle was labelled with 111In for biodistribution assessment, and subsequent cycles were administered 3 weekly to a maximum of 6 cycles. Tumour targeting was assessed using SPECT imaging, and pharmacokinetic analysis was based on gamma counting (111In-CMD-193) and ELISA (CMD-193 protein). Results: Nine patients were enrolled, and received 1-6 treatment cycles. Biodistribution imaging demonstrated initial blood pooling, followed by markedly increased hepatic uptake by day 2 (which persisted to day 8), and fast blood clearance. This pattern was seen for all patients, with no significant tumour uptake visualised in any patient. The overall T 1 /2 of 111In-CMD-193 complex formation in blood. One patient had partial metabolic response on 18F-FDG-PET. No radiologic responses were observed. Conclusions: CMD-193 demonstrates rapid blood clearance and increased hepatic uptake compared to prior studies of the original non-conjugated antibody. This trial highlights the importance of biodistribution and pharmacodynamic assessment in early phase studies of new biologics in clinical development.

  15. Anti-colchicine Fab fragments prevent lethal colchicine toxicity in a porcine model: a pharmacokinetic and clinical study.

    Science.gov (United States)

    Eddleston, Michael; Fabresse, Nicolas; Thompson, Adrian; Al Abdulla, Ibrahim; Gregson, Rachael; King, Tim; Astier, Alain; Baud, Frederic J; Clutton, R Eddie; Alvarez, Jean-Claude

    2018-08-01

    Colchicine poisoning is commonly lethal. Colchicine-specific Fab fragments increase rat urinary colchicine clearance and have been associated with a good outcome in one patient. We aimed to develop a porcine model of colchicine toxicity to study the pharmacokinetics and efficacy of ovine Fab. A Göttingen minipig critical care model was established and serial blood samples taken for colchicine and Fab pharmacokinetics, clinical chemistry, and haematology. Animals were euthanised when the mean arterial pressure fell below 45 mmHg without response to vasopressor, or at study completion. Initial studies indicated that oral dosing produced variable pharmacokinetics and time-to-euthanasia. By contrast, intravenous infusion of 0.25 mg/kg colchicine over 1 h produced reproducible pharmacokinetics (AUC 0-20 343 [SD = 21] µg/L/h), acute multi-organ injury, and cardiotoxicity requiring euthanasia a mean of 22.5 (SD = 3.2) h after dosing. A full-neutralising equimolar Fab dose given 6 h after the infusion (50% first hour, 50% next 6 h [to reduce renal-loss of unbound Fab]) produced a 7.35-fold increase in plasma colchicine (AUC 0-20 2,522 [SD = 14] µg/L/h), and removed all free plasma colchicine, but did not prevent toxicity (euthanasia at 29.1 [SD = 3.4] h). Earlier administration over 1 h of the full-neutralising dose, 1 or 3 h after the colchicine, produced a 12.9-fold (AUC 0-20 4,433 [SD = 607] µg/L/h) and 6.0-fold (AUC 0-20 2,047 [SD = 51] µg/L/h) increase in plasma colchicine, respectively, absence of free plasma colchicine until 20 h, and survival to study end without marked cardiotoxicity. Colchicine-specific Fab given early, in equimolar dose, bound colchicine, eliciting its movement into the blood, and preventing severe toxicity. Clinical studies are now needed to determine how soon this antidote must be given to work in human poisoning.

  16. Observational infant exploratory [14C]-paracetamol pharmacokinetic microdose/therapeutic dose study with accelerator mass spectrometry bioanalysis

    Science.gov (United States)

    Garner, Colin R; Park, Kevin B; French, Neil S; Earnshaw, Caroline; Schipani, Alessandro; Selby, Andrew M; Byrne, Lindsay; Siner, Sarah; Crawley, Francis P; Vaes, Wouter H J; van Duijn, Esther; deLigt, Rianne; Varendi, Heili; Lass, Jane; Grynkiewicz, Grzegorz; Maruszak, Wioletta; Turner, Mark A

    2015-01-01

    Aims The aims of the study were to compare [14C]-paracetamol ([14C]-PARA) paediatric pharmacokinetics (PK) after administration mixed in a therapeutic dose or an isolated microdose and to develop further and validate accelerator mass spectrometry (AMS) bioanalysis in the 0–2 year old age group. Methods [14C]-PARA concentrations in 10–15 µl plasma samples were measured after enteral or i.v. administration of a single [14C]-PARA microdose or mixed in with therapeutic dose in infants receiving PARA as part of their therapeutic regimen. Results Thirty-four infants were included in the PARA PK analysis for this study: oral microdose (n = 4), i.v. microdose (n = 6), oral therapeutic (n = 6) and i.v. therapeutic (n = 18). The respective mean clearance (CL) values (SDs in parentheses) for these dosed groups were 1.46 (1.00) l h–1, 1.76 (1.07) l h–1, 2.93 (2.08) l h–1 and 2.72 (3.10) l h–1, t1/2 values 2.65 h, 2.55 h, 8.36 h and 7.16 h and dose normalized AUC(0-t) (mg l–1 h) values were 0.90 (0.43), 0.84 (0.57), 0.7 (0.79) and 0.54 (0.26). Conclusions All necessary ethical, scientific, clinical and regulatory procedures were put in place to conduct PK studies using enteral and systemic microdosing in two European centres. The pharmacokinetics of a therapeutic dose (mg kg–1) and a microdose (ng kg–1) in babies between 35 to 127 weeks post-menstrual age. [14C]-PARA pharmacokinetic parameters were within a two-fold range after a therapeutic dose or a microdose. Exploratory studies using doses significantly less than therapeutic doses may offer ethical and safety advantages with increased bionalytical sensitivity in selected exploratory paediatric pharmacokinetic studies. PMID:25619398

  17. Observational infant exploratory [(14)C]-paracetamol pharmacokinetic microdose/therapeutic dose study with accelerator mass spectrometry bioanalysis.

    Science.gov (United States)

    Garner, Colin R; Park, Kevin B; French, Neil S; Earnshaw, Caroline; Schipani, Alessandro; Selby, Andrew M; Byrne, Lindsay; Siner, Sarah; Crawley, Francis P; Vaes, Wouter H J; van Duijn, Esther; deLigt, Rianne; Varendi, Heili; Lass, Jane; Grynkiewicz, Grzegorz; Maruszak, Wioletta; Turner, Mark A

    2015-07-01

    The aims of the study were to compare [(14)C]-paracetamol ([(14)C]-PARA) paediatric pharmacokinetics (PK) after administration mixed in a therapeutic dose or an isolated microdose and to develop further and validate accelerator mass spectrometry (AMS) bioanalysis in the 0-2 year old age group. [(14)C]-PARA concentrations in 10-15 µl plasma samples were measured after enteral or i.v. administration of a single [(14)C]-PARA microdose or mixed in with therapeutic dose in infants receiving PARA as part of their therapeutic regimen. Thirty-four infants were included in the PARA PK analysis for this study: oral microdose (n = 4), i.v. microdose (n = 6), oral therapeutic (n = 6) and i.v. therapeutic (n = 18). The respective mean clearance (CL) values (SDs in parentheses) for these dosed groups were 1.46 (1.00) l h(-1), 1.76 (1.07) l h(-1), 2.93 (2.08) l h(-1) and 2.72 (3.10) l h(-1), t(1/2) values 2.65 h, 2.55 h, 8.36 h and 7.16 h and dose normalized AUC(0-t) (mg l(-1) h) values were 0.90 (0.43), 0.84 (0.57), 0.7 (0.79) and 0.54 (0.26). All necessary ethical, scientific, clinical and regulatory procedures were put in place to conduct PK studies using enteral and systemic microdosing in two European centres. The pharmacokinetics of a therapeutic dose (mg kg(-1)) and a microdose (ng kg(-1)) in babies between 35 to 127 weeks post-menstrual age. [(14)C]-PARA pharmacokinetic parameters were within a two-fold range after a therapeutic dose or a microdose. Exploratory studies using doses significantly less than therapeutic doses may offer ethical and safety advantages with increased bionalytical sensitivity in selected exploratory paediatric pharmacokinetic studies. © 2015 The British Pharmacological Society.

  18. Potent human uric acid transporter 1 inhibitors: in vitro and in vivo metabolism and pharmacokinetic studies

    Directory of Open Access Journals (Sweden)

    Wempe MF

    2012-11-01

    Full Text Available Michael F Wempe,1 Janet W Lightner,2 Bettina Miller,1 Timothy J Iwen,1 Peter J Rice,1 Shin Wakui,3 Naohiko Anzai,4 Promsuk Jutabha,4 Hitoshi Endou51Department of Pharmaceutical Sciences, School of Pharmacy, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO, USA; 2Department of Pharmacology, East Tennessee State University, Johnson City, TN, USA; 3Department of Toxicology, Azabu University School of Veterinary Medicine, Chuo Sagamihara, Kanagawa, Japan; 4Department of Pharmacology and Toxicology, Dokkyo Medical University School of Medicine, Mibu, Shimotsuga, Tochigi, Japan; 5Department of Pharmacology and Toxicology, Kyorin University School of Medicine, Mitaka, Tokyo, JapanAbstract: Human uric acid transporter 1 (hURAT1; SLC22A12 is a very important urate anion exchanger. Elevated urate levels are known to play a pivotal role in cardiovascular diseases, chronic renal disease, diabetes, and hypertension. Therefore, the development of potent uric acid transport inhibitors may lead to novel therapeutic agents to combat these human diseases. The current study investigates small molecular weight compounds and their ability to inhibit 14C-urate uptake in oocytes expressing hURAT1. Using the most promising drug candidates generated from our structure–activity relationship findings, we subsequently conducted in vitro hepatic metabolism and pharmacokinetic (PK studies in male Sprague-Dawley rats. Compounds were incubated with rat liver microsomes containing cofactors nicotinamide adenine dinucleotide phosphate and uridine 5'-diphosphoglucuronic acid. In vitro metabolism and PK samples were analyzed using liquid chromatography/mass spectrometry-mass spectrometry methods. Independently, six different inhibitors were orally (capsule dosing or intravenously (orbital sinus administered to fasting male Sprague-Dawley rats. Blood samples were collected and analyzed; these data were used to compare in vitro and in vivo metabolism and to

  19. Pharmacokinetic interaction between udenafil and dapoxetine: a randomized, open-labeled crossover study in healthy male volunteers

    Directory of Open Access Journals (Sweden)

    Kim YH

    2015-02-01

    Full Text Available Yo Han Kim,1 Hee Youn Choi,1 Shi Hyang Lee,1 Hae Sun Jeon,1 Hyeong-Seok Lim,1 Mi Young Bahng,2 Kyun-Seop Bae1 1Department of Clinical Pharmacology and Therapeutics, Asan Medical Center, College of Medicine, University of Ulsan, 2Clinical Development Department, Dong-A ST Co, Ltd, Seoul, Republic of Korea Background: “Udenafil” is a phosphodiesterase-5 inhibitor indicated for erectile dysfunction. “Dapoxetine” is a serotonin transport inhibitor indicated for premature ejaculation. The aim of the study reported here was to investigate the pharmacokinetic drug interaction between udenafil and dapoxetine in healthy male subjects. Methods: An open-label, three-treatment, six-sequence, three-period crossover study was performed in healthy male subjects. In varying sequences, each subjects received single oral doses of udenafil 200 mg, dapoxetine 60 mg, and both treatments. The periods were separated by a washout period of 7 days. Serial blood samples were collected up to 48 hours after dosing. The plasma concentrations of udenafil and dapoxetine were determined using a validated liquid chromatography-tandem mass spectrometry method. Pharmacokinetic parameters were obtained by non-compartmental analysis. Tolerability was assessed throughout the study. Results: Twenty-three healthy subjects completed the study. The geometric mean ratios of the area under the plasma concentration–time curve from time 0 to last measurable time point and measured peak plasma concentration for udenafil were 0.923 (90% confidence interval [CI]: 0.863–0.987 and 0.864 (90% CI: 0.789–0.947, respectively. The geometric mean ratios of the area under the plasma concentration–time curve from time 0 to last measurable time point and measured peak plasma concentration for dapoxetine were 1.125 (90% CI: 1.044–1.213 and 0.837 (90% CI: 0.758–0.925, respectively. There were no serious adverse events reported, and none of the subjects dropped out due to adverse events

  20. The pharmacokinetic study of rutin in rat plasma based on an electrochemically reduced graphene oxide modified sensor

    Directory of Open Access Journals (Sweden)

    Pei Zhang

    2016-04-01

    Full Text Available An electrochemical method based on a directly electrochemically reduced graphene oxide (ERGO film coated on a glassy carbon electrode (GCE was developed for the rapid and convenient determination of rutin in plasma. ERGO was modified on the surface of GCE by one-step electro-deposition method. Electrochemical behavior of rutin on ERGO/GCE indicated that rutin underwent a surface-controlled quasi-reversible process and the electrochemical parameters such as charge transfer coefficient (α, electron transfer number (n and electrode reaction standard rate constant (ks were 0.53, 2 and 3.4 s−1, respectively. The electrochemical sensor for rutin in plasma provided a wide linear response range of 4.70×10−7−1.25×10−5 M with the detection limit (s/n=3 of 1.84×10−8 M. The assay was successfully used to the pharmacokinetic study of rutin. The pharmacokinetic parameters such as elimination rate half-life (t1/2, area under curve (AUC, and plasma clearance (CL were calculated to be 3.345±0.647 min, 5750±656.0 µg min/mL, and 5.891±0.458 mL/min/kg, respectively. The proposed method utilized a small sample volume of 10 μL and had no complicated sample pretreatment (without deproteinization, which was simple, eco-friendly, and time- and cost-efficient for rutin pharmacokinetic studies.

  1. Effects of chlorophyll and chlorophyllin on low-dose aflatoxin B1 pharmacokinetics in human volunteers: A pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Jubert, C; Mata, J; Bench, G; Dashwood, R; Pereira, C; Tracewell, W; Turteltaub, K; Williams, D; Bailey, G

    2009-04-20

    Chlorophyll (Chla) and chlorophyllin (CHL) were shown previously to reduce carcinogen bioavailability, biomarker damage, and tumorigenicity in trout and rats. These findings were partially extended to humans (Proc Natl Acad Sci USA 98, 14601-14606 (2001)), where CHL reduced excretion of aflatoxin B{sub 1} (AFB{sub 1})-DNA repair products in Chinese unavoidably exposed to dietary AFB{sub 1}. However, neither AFB{sub 1} pharmacokinetics nor Chla effects were examined. We conducted a small unblinded crossover study to establish AFB{sub 1} pharmacokinetic parameters in human volunteers, and to explore possible effects of CHL or Chla co-treatment on those parameters. For protocol 1, fasted subjects received an IRB-approved dose of 14C-AFB{sub 1} (30 ng, 5 nCi) by capsule with 100 ml water, followed by normal eating and drinking after hr 2. Blood and cumulative urine samples were collected over 72 hr, and {sup 14}C-AFB{sub 1} equivalents were determined by Accelerator Mass Spectrometry. Protocols 2 and 3 were similar except capsules also contained 150 mg of purified Chla, or CHL, respectively. All protocols were repeated 3 times for each of three volunteers. The study revealed rapid human AFB{sub 1} uptake (plasma ka 5.05 {+-} 1.10 hr-1, Tmax 1.0 hr) and urinary elimination (95% complete by 24 hr) kinetics. Chla and CHL treatment each significantly impeded AFB{sub 1} absorption and reduced Cmax and AUC's (plasma and urine) in one or more subjects. These initial results provide AFB{sub 1} pharmacokinetic parameters previously unavailable for humans, and suggest that Chla or CHL co-consumption may limit the bioavailability of ingested aflatoxin in humans, as they do in animal models.

  2. Rats and rabbits as pharmacokinetic screening tools for long acting intramuscular depots: case study with paliperidone palmitate suspension.

    Science.gov (United States)

    Patel, Harilal; Patel, Prakash; Modi, Nirav; Patel, Pinakin; Wagh, Yogesh; George, Alex; Desai, Nirmal; Srinivas, Nuggehally R

    2018-05-08

    Development of prodrug of 9-hydroxyrisperidone (paliperidone) long-acting intramuscular injection has enabled delivery over four-week time period with improved compliance. The key aim of this work was to establish a reliable preclinical model which may potentially serve as a screening tool for judging the pharmacokinetics of paliperidone formulation(s) prior to human clinical work. Sparse sampling composite study was used in rats, (Wistar/Sprague-Dawley (SD; n = 10)) and a serial blood sampling study design was used in rabbits (n = 4). Animals received intramuscular injection of paliperidone palmitate in the thigh muscle at dose of 16 (rats) and 4.5 mg/kg (rabbits). Samples were drawn in rats (retro-orbital sinus) and rabbits (central ear artery) and were analysed for paliperidone using liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS) assay. The plasma data was subjected to pharmacokinetic analysis. Following intramuscular injection of depot formulation in Wistar/SD rats and rabbits, absorption of paliperidone was slow and gradual with median value of time to reach maximum concentration (T max ) occurring on day 7. The exposures (i.e. area under the curve (AUC; 0-28) days) were 18,597, 21,865 and 18,120 ng.h/mL, in Wistar, SD and rabbits, respectively. The clearance was slow and supported long half-life (8-10 days). Either one of the two models can serve as a research tool for establishing pharmacokinetics of paliperidone formulation(s).

  3. Comparison of propofol pharmacokinetic and pharmacodynamic models for awake craniotomy: A prospective observational study.

    Science.gov (United States)

    Soehle, Martin; Wolf, Christina F; Priston, Melanie J; Neuloh, Georg; Bien, Christian G; Hoeft, Andreas; Ellerkmann, Richard K

    2015-08-01

    Anaesthesia for awake craniotomy aims for an unconscious patient at the beginning and end of surgery but a rapidly awakening and responsive patient during the awake period. Therefore, an accurate pharmacokinetic/pharmacodynamic (PK/PD) model for propofol is required to tailor depth of anaesthesia. To compare the predictive performances of the Marsh and the Schnider PK/PD models during awake craniotomy. A prospective observational study. Single university hospital from February 2009 to May 2010. Twelve patients undergoing elective awake craniotomy for resection of brain tumour or epileptogenic areas. Arterial blood samples were drawn at intervals and the propofol plasma concentration was determined. The prediction error, bias [median prediction error (MDPE)] and inaccuracy [median absolute prediction error (MDAPE)] of the Marsh and the Schnider models were calculated. The secondary endpoint was the prediction probability PK, by which changes in the propofol effect-site concentration (as derived from simultaneous PK/PD modelling) predicted changes in anaesthetic depth (measured by the bispectral index). The Marsh model was associated with a significantly (P = 0.05) higher inaccuracy (MDAPE 28.9 ± 12.0%) than the Schnider model (MDAPE 21.5 ± 7.7%) and tended to reach a higher bias (MDPE Marsh -11.7 ± 14.3%, MDPE Schnider -5.4 ± 20.7%, P = 0.09). MDAPE was outside of accepted limits in six (Marsh model) and two (Schnider model) of 12 patients. The prediction probability was comparable between the Marsh (PK 0.798 ± 0.056) and the Schnider model (PK 0.787 ± 0.055), but after adjusting the models to each individual patient, the Schnider model achieved significantly higher prediction probabilities (PK 0.807 ± 0.056, P = 0.05). When using the 'asleep-awake-asleep' anaesthetic technique during awake craniotomy, we advocate using the PK/PD model proposed by Schnider. Due to considerable interindividual variation, additional monitoring of anaesthetic depth is

  4. Mycophenolate pharmacokinetics and pharmacodynamics in belatacept treated renal allograft recipients – a pilot study

    Directory of Open Access Journals (Sweden)

    Stenstrøm Jean

    2009-07-01

    Full Text Available Abstract Background Mycophenolic acid (MPA is widely used as part of immunosuppressive regimens following allograft transplantation. The large pharmacokinetic (PK and pharmacodynamic (PD variability and narrow therapeutic range of MPA provide a potential for therapeutic drug monitoring. The objective of this pilot study was to investigate the MPA PK and PD relation in combination with belatacept (2nd generation CTLA4-Ig or cyclosporine (CsA. Methods Seven renal allograft recipients were randomized to either belatacept (n = 4 or cyclosporine (n = 3 based immunosuppression. Samples for MPA PK and PD evaluations were collected predose and at 1, 2 and 13 weeks posttransplant. Plasma concentrations of MPA were determined by HPLC-UV. Activity of inosine monophosphate dehydrogenase (IMPDH and the expressions of two IMPDH isoforms were measured in CD4+ cells by HPLC-UV and real-time reverse-transcription PCR, respectively. Subsets of T cells were characterized by flow cytometry. Results The MPA exposure tended to be higher among belatacept patients than in CsA patients at week 1 (P = 0.057. Further, MPA concentrations (AUC0–9 h and C0 increased with time in both groups and were higher at week 13 than at week 2 (P = 0.031, n = 6. In contrast to the postdose reductions of IMPDH activity observed early posttransplant, IMPDH activity within both treatment groups was elevated throughout the dosing interval at week 13. Transient postdose increments were also observed for IMPDH1 expression, starting at week 1. Higher MPA exposure was associated with larger elevations of IMPDH1 (r = 0.81, P = 0.023, n = 7 for MPA and IMPDH1 AUC0–9 h at week 1. The maximum IMPDH1 expression was 52 (13–177% higher at week 13 compared to week 1 (P = 0.031, n = 6. One patient showed lower MPA exposure with time and did neither display elevations of IMPDH activity nor IMPDH1 expression. No difference was observed in T cell subsets between treatment groups. Conclusion The

  5. Using Nonexperts for Annotating Pharmacokinetic Drug-Drug Interaction Mentions in Product Labeling: A Feasibility Study.

    Science.gov (United States)

    Hochheiser, Harry; Ning, Yifan; Hernandez, Andres; Horn, John R; Jacobson, Rebecca; Boyce, Richard D

    2016-04-11

    Because vital details of potential pharmacokinetic drug-drug interactions are often described in free-text structured product labels, manual curation is a necessary but expensive step in the development of electronic drug-drug interaction information resources. The use of nonexperts to annotate potential drug-drug interaction (PDDI) mentions in drug product label annotation may be a means of lessening the burden of manual curation. Our goal was to explore the practicality of using nonexpert participants to annotate drug-drug interaction descriptions from structured product labels. By presenting annotation tasks to both pharmacy experts and relatively naïve participants, we hoped to demonstrate the feasibility of using nonexpert annotators for drug-drug information annotation. We were also interested in exploring whether and to what extent natural language processing (NLP) preannotation helped improve task completion time, accuracy, and subjective satisfaction. Two experts and 4 nonexperts were asked to annotate 208 structured product label sections under 4 conditions completed sequentially: (1) no NLP assistance, (2) preannotation of drug mentions, (3) preannotation of drug mentions and PDDIs, and (4) a repeat of the no-annotation condition. Results were evaluated within the 2 groups and relative to an existing gold standard. Participants were asked to provide reports on the time required to complete tasks and their perceptions of task difficulty. One of the experts and 3 of the nonexperts completed all tasks. Annotation results from the nonexpert group were relatively strong in every scenario and better than the performance of the NLP pipeline. The expert and 2 of the nonexperts were able to complete most tasks in less than 3 hours. Usability perceptions were generally positive (3.67 for expert, mean of 3.33 for nonexperts). The results suggest that nonexpert annotation might be a feasible option for comprehensive labeling of annotated PDDIs across a broader

  6. Quantitative determination of metaxalone in human plasma by LC-MS and its application in a pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Lanting Zhao

    2016-10-01

    Full Text Available A simple and rapid method using liquid chromatography–mass spectrometry (LC-MS for the determination of metaxalone in human plasma has been developed and validated. Letrozole was used as the internal standard (IS. The plasma samples were simply treated with acetonitrile which allowed the precipitation of plasma proteins. The chromatographic separation was achieved on a Sapphire C18 (2.1 mm × 150 mm, 5 µm, Newark, USA column using the mobile phase (5 mM ammonium acetate containing 0.01% formic acid: acetonitrile (45:55, v/v at a flow rate of 0.3 ml/min. The selected ion monitoring (SIM in the positive mode was used for the determination of [M + H]+ m/z 222.1 and 286.1 for metaxalone and letrozole, respectively. The standard curve obtained was linear (r2 ≥ 0.99 over the concentration range of 30.24−5040 ng/ml. Meanwhile, no interfering peaks or matrix effect was observed. The method established was simple and successfully applied to a pharmacokinetic study of metaxalone in healthy Chinese volunteers after a single oral dose administration of 800 mg metaxalone. The main pharmacokinetic parameters of metaxalone were as follow: Cmax, (1664 ± 1208 ng/ml and (2063 ± 907 ng/ml; AUC0−36, (13925 ± 6590 ng/ml h and (18620 ± 5717 ng/ml h; t1/2, (13.6 ± 7.7 h and (20.3 ± 7.7 h for the reference and test tablets, respectively. These pharmacokinetic parameters of metaxalone in healthy Chinese volunteers were reported for the first time.

  7. Leveraging model-based study designs and serial micro-sampling techniques to understand the oral pharmacokinetics of the potent LTB4 inhibitor, CP-105696, for mouse pharmacology studies.

    Science.gov (United States)

    Spilker, Mary E; Chung, Heekyung; Visswanathan, Ravi; Bagrodia, Shubha; Gernhardt, Steven; Fantin, Valeria R; Ellies, Lesley G

    2017-07-01

    1. Leukotriene B4 (LTB4) is a proinflammatory mediator important in the progression of a number of inflammatory diseases. Preclinical models can explore the role of LTB4 in pathophysiology using tool compounds, such as CP-105696, that modulate its activity. To support preclinical pharmacology studies, micro-sampling techniques and mathematical modeling were used to determine the pharmacokinetics of CP-105696 in mice within the context of systemic inflammation induced by a high-fat diet (HFD). 2. Following oral administration of doses > 35 mg/kg, CP-105696 kinetics can be described by a one-compartment model with first order absorption. The compound's half-life is 44-62 h with an apparent volume of distribution of 0.51-0.72 L/kg. Exposures in animals fed an HFD are within 2-fold of those fed a normal chow diet. Daily dosing at 100 mg/kg was not tolerated and resulted in a >20% weight loss in the mice. 3. CP-105696's long half-life has the potential to support a twice weekly dosing schedule. Given that most chronic inflammatory diseases will require long-term therapies, these results are useful in determining the optimal dosing schedules for preclinical studies using CP-105696.

  8. Influence of B{sub 1}-inhomogeneity on pharmacokinetic modeling of dynamic contrast-enhanced MRI: A simulation study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Bun Woo [Dept. of Radiology, Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of); Choi, Byung Se [Dept. of Radiology, Seoul National University College of Medicine, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); and others

    2017-08-01

    To simulate the B1-inhomogeneity-induced variation of pharmacokinetic parameters on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). B1-inhomogeneity-induced flip angle (FA) variation was estimated in a phantom study. Monte Carlo simulation was performed to assess the FA-deviation-induced measurement error of the pre-contrast R1, contrast-enhancement ratio, Gd-concentration, and two-compartment pharmacokinetic parameters (Ktrans, ve, and vp). B1-inhomogeneity resulted in −23–5% fluctuations (95% confidence interval [CI] of % error) of FA. The 95% CIs of FA-dependent % errors in the gray matter and blood were as follows: −16.7–61.8% and −16.7–61.8% for the pre-contrast R1, −1.0–0.3% and −5.2–1.3% for the contrast-enhancement ratio, and −14.2–58.1% and −14.1–57.8% for the Gd-concentration, respectively. These resulted in −43.1–48.4% error for Ktrans, −32.3–48.6% error for the ve, and −43.2–48.6% error for vp. The pre-contrast R1 was more vulnerable to FA error than the contrast-enhancement ratio, and was therefore a significant cause of the Gd-concentration error. For example, a −10% FA error led to a 23.6% deviation in the pre-contrast R1, −0.4% in the contrast-enhancement ratio, and 23.6% in the Gd-concentration. In a simulated condition with a 3% FA error in a target lesion and a −10% FA error in a feeding vessel, the % errors of the pharmacokinetic parameters were −23.7% for Ktrans, −23.7% for ve, and −23.7% for vp. Even a small degree of B1-inhomogeneity can cause a significant error in the measurement of pharmacokinetic parameters on DCE-MRI, while the vulnerability of the pre-contrast R1 calculations to FA deviations is a significant cause of the miscalculation.

  9. A Preliminary Pharmacokinetic Study of Betulin, the Main Pentacyclic Triterpene from Extract of Outer Bark of Birch (Betulae alba cortex

    Directory of Open Access Journals (Sweden)

    Melanie N. Laszczyk

    2008-12-01

    Full Text Available During the last two decades triterpenes have attracted attention because of their pharmacological potential. Triterpene extract (TE from outer bark of birch consisting mainly of betulin is able to form an oleogel which was successfully tested in the treatment of actinic keratosis. Some aspects of TE in vitro pharmacology are already known. Now we show preliminary pharmacokinetics of betulin and results of a subchronic toxicity study of TE in rats and dogs. Because of poor aqueous solubility of the TE-triterpenes (< 0.1 μg/mL respectively, for pharmacokinetic studies it was suspended in sesame oil (rats, i.p. and PEG 400 / 0.9 % NaCl (dogs, s.c.. I.p. administered, betulin, the main component of TE, shows time dependency over a period of 4 h and reaches a dose-independent serum level of 0.13 μg/mL. Dose dependency was observed with s.c. administration. At 300 mg/kg a maximum plasma concentration of 0.33 μg/mL betulin was detected after 28 daily applications. The subchronic toxicity study showed no toxicity of TE in rats (i.p. and dogs (s.c.. In conclusion, triterpene extract from birch bark is safe, its betulin is bioavailable and in addition to published triterpene biological activities TE provides high potential for further pharmaceutical and pharmacological research.

  10. Study on pharmacokinetics of 3,4-divanillyltetrahydrofuran in rats by ultra-fast liquid chromatography/tandem mass spectrometry.

    Science.gov (United States)

    Shan, Chen-Xiao; Cui, Xiao-Bing; Yu, Sheng; Chai, Chuan; Wen, Hong-Mei; Wang, Xin-Zhi; Sun, Xue

    2016-01-01

    3,4-Divanillyltetrahydrofuran is the main active ingredient of nettle root which can increase steroid hormones in the bloodstream for many of bodybuilders. To better understand its pharmacological activities, we need to determine its pharmacokinetic profiles. In this study, a rapid and sensitive ultra-fast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) method has been developed for the determination of 3,4-divanillyltetrahydrofuran in the plasma of rats. Chromatographic separation was performed on a C18 column at 40°C, with a gradient elution consisting of methanol and water containing 0.3% (v/v) formic acid at a flow rate of 0.8mL/min. The detection was performed using an electrospray triple-quadrupole MS/MS via positive ion multiple reaction monitoring mode. The lower limits-of-quantification determined were 0.5ng/mL. The intra- and inter-day precision (RSD%) was found to be within 15% and the accuracy (RE%) ranged from -4.0% to 7.0%. This simple yet sensitive method was fully validated and could be successfully applied to the study on pharmacokinetics of 3, 4-divanillyltetrahydrofuran. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Pharmacodynamic and pharmacokinetic studies and prostatic tissue distribution of fosfomycin tromethamine in bacterial prostatitis or normal rats.

    Science.gov (United States)

    Fan, L; Shang, X; Zhu, J; Ma, B; Zhang, Q

    2018-05-02

    In this study, we assessed the therapeutic effects of fosfomycin tromethamine (FT) in a bacterial prostatitis (BP) rat model. The BP model was induced by Escherichia coli and was demonstrated after 7 days microbiologically and histologically. Then, 25 BP rats selected were randomly divided into five treatment groups: model group, positive group, FT-3 day group, FT-7 day group and FT-14 day group. Ventral lobes of prostate from all animals were removed, and the serum samples were collected at the end of the experiments. Microbiological cultures and histological findings of the prostate samples demonstrated reduced bacterial growth and improved inflammatory responses in FT-treatment groups compared with the model group, indicating that FT against prostatic infection induced by E. coli showed good antibacterial effects. Moreover, plasma pharmacokinetics and prostatic distribution of fosfomycin were studied and compared in BP and normal rats. The concentrations of fosfomycin in samples were analysed by liquid chromatography-tandem mass spectrometry. There were no differences in plasma pharmacokinetic parameters between two groups. But significantly higher penetration of fosfomycin into prostatic tissues was found in BP rats. We therefore suggested that FT had a good therapeutic effect on BP and it might be used in curing masculine reproductive system diseases. © 2018 Blackwell Verlag GmbH.

  12. Experimental study of the anti-tumour activity and pharmacokinetics of arctigenin and its valine ester derivative.

    Science.gov (United States)

    Cai, Enbo; Song, Xingzhuo; Han, Mei; Yang, Limin; Zhao, Yan; Li, Wei; Han, Jiahong; Tu, Shumei

    2018-02-19

    Arctigenin (ARG) is a functional active component that has important physiological and pharmacological activities. The anti-tumour and anti-inflammatory activities of ARG show good potential for application and development, but this material has the defect of low water solubility. In this experiment, the valine derivative of ARG (ARG-V) was designed and synthesized to overcome this disadvantage. The ARG amino acid, EDCI and DMAP were raw materials in the addition reaction, with a molar ratio of 1:2:2:0.5. The yield of ARG-V was up to 80%. ARG-V has strong anti-tumour activity in vivo and in vitro. The inhibitory rate of ARG-V was 69.2%, with less damage to the immune organs and different degrees of increased serum cytotoxicity. Moreover, the pharmacokinetics of ARG following oral administration and ARG-V following oral administration in rats were also studied. The C max and AUC values of ARG-V showed significant differences compared to ARG. The relative bioavailabilities of three doses of ARG-V compared to ARG were 664.7%, 741.5% and 812.9%. These pharmacokinetic results may be useful for further studies of the bioactive mechanism of ARG and provide a theoretical basic for clinical use.

  13. Autobacteriographic studies of clarithromycin and erythromycin in mice

    International Nuclear Information System (INIS)

    Kohno, Y.; Ohta, K.; Suwa, T.; Suga, T.

    1990-01-01

    The antimicrobial activity of clarithromycin was compared with that of erythromycin in experimentally infected mice by whole-body autobacteriography. In mice with systemic staphylococcal infections, the number of vital microbes in the body was relatively low in the early period after oral administration of erythromycin, but increased thereafter to the levels found in nonmedicated control mice. On the other hand, with clarithromycin treatment, a significantly smaller number of microbes was evident throughout the body. The microbes were scarcely seen in the parenchyma of any organs during the examination period. This potent antimicrobial activity of clarithromycin compared with that of erythromycin was further demonstrated in mice with respiratory infections. On the other hand, to examine the distribution properties of both antibiotics in the whole body, an autoradiographic study was carried out with [N-methyl-14C]clarithromycin and [N-methyl-14C]erythromycin. Both labeled antibiotics were distributed widely throughout the body after oral administration in both uninfected control mice and mice with systemic infections. However, the radioactivity was more marked and persistent for [14C]clarithromycin than it was for [14C]erythromycin, particularly in the lungs. The observations described above indicate the superior in vivo antimicrobial activity of clarithromycin compared with that of erythromycin and suggest that the superiority of clarithromycin is largely attributed to its favorable distribution properties. The advantages of whole-body autobacteriography, coupled with whole-body autoradiography, are discussed

  14. Preclinical safety, pharmacokinetics, pharmacodynamics, and biodistribution studies with Ad35K++ protein: a novel rituximab cotherapeutic

    Directory of Open Access Journals (Sweden)

    Maximilian Richter

    2016-01-01

    Full Text Available Rituximab is a mouse/human chimeric monoclonal antibody targeted toward CD20. It is efficient as first-line therapy of CD20-positive B-cell malignancies. However, a large fraction of treated patients relapse with rituximab-resistant disease. So far, only modest progress has been made in treatment options for rituximab refractory patients. One of the mechanisms for rituximab resistance involves the upregulation of CD46, which is a key cell surface protein that blocks the activation of complement. We have recently developed a technology that depletes CD46 from the cell surface and thereby sensitizes tumor cells to complement-dependent cytotoxicity. This technology is based on a small recombinant protein, Ad35K++ that binds with high affinity to CD46. In preliminary studies using a 6 × histidinyl tagged protein, we had demonstrated that intravenous Ad35K++ injection in combination with rituximab was safe and increased rituximab-mediated killing of CD20-positive target cells in mice and nonhuman primates (NHPs. The presence of the tag, while allowing for easy purification by Ni-NTA chromatography, has the potential to increase the immunogenicity of the recombinant protein. For clinical application, we therefore developed an Ad35K++ protein without His-tag. In the present study, we performed preclinical studies in two animal species (mice and NHPs with this protein demonstrating its safety and efficacy. These studies estimated the Ad35K++ dose range and treatment regimen to be used in patients. Furthermore, we showed that intravenous Ad35K++ injection triggers the shedding of the CD46 extracellular domain in xenograft mouse tumor models and in macaques. Shed serum CD46 can be measured in the serum and can potentially be used as a pharmacodynamic marker for monitoring Ad35K++ activity in patient undergoing treatment with this agent. These studies create the basis for an investigational new drug application for the use of Ad35K++ in combination with

  15. Heritability of metoprolol and torsemide pharmacokinetics

    DEFF Research Database (Denmark)

    Matthaei, Johannes; Brockmöller, Jürgen; Tzvetkov, Mladen

    2015-01-01

    Genetic variation in the pharmacokinetics of metoprolol and torsemide due to polymorphisms in CYP2D6, CYP2C9 and OATP1B1 has been extensively studied. However, it is still unknown how much of variation in pharmacokinetics of these two clinically important drugs in total is due to genetic factors....... of the heritable variability in the pharmacokinetics of metoprolol and torsemide remains to be elucidated. This article is protected by copyright. All rights reserved....

  16. A novel oil-body nanoemulsion formulation of ginkgolide B: pharmacokinetics study and in vivo pharmacodynamics evaluations.

    Science.gov (United States)

    Yang, Pengfei; Cai, Xiaolei; Zhou, Kai; Lu, Chuanhua; Chen, Weidong

    2014-04-01

    The goal of this study was to develop a novel oil-body nanoemulsion (ONE) for Ginkgolide B (GB) and to conduct pharmacokinetics and pharmacodynamics evaluations. GB-ONE was prepared by O/O emulsion method. The differences in pharmacokinetics parameters and tissue distribution of rats after oral administrated with GB-ONE were investigated by liquid chromatography-tandem mass spectrometry. Changes in the ethological and pathological characterizations of the Alzheimer's disease rats after treated with GB-ONE were evaluated by Morris water maze (MWM) and pathological section, respectively. Furthermore, choline acetyltransferase (ChAT) and acetylcholinesterase (AchE) activity in hippocampus was analyzed by spectrophotometric method. The results indicated that the AUC of GB in rats' plasma was significantly improved after incorporated into ONE, and GB-ONE was significantly targeted into brain. In MWM experiment, memory improvement of rats with cognition impaired was confirmed after administrated with GB-ONE. Furthermore, GB-ONE significantly inhibited AchE activity and enhanced the activity of ChAT in the hippocampus. The overall results implicated that the novel ONE was effective for improving the drawbacks of GB and showed great potential for clinical application. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  17. [Determination of ferulic acid absorbed into human serum from oral decoction of rhizoma chuanxiong and pharmacokinetic study of ferulic acid].

    Science.gov (United States)

    Sun, S; Huang, X; Zhang, L; Ren, P; Chang, Z

    2001-10-01

    To improve the HPLC method for determining ferulic acid(FA) in the human serum and to research FA clinical pharmacokinetics. Serum concentrations of FA were determined by HPLC using methanol-water-acetic acid (40:59.7:0.3, v/v) as the mobile phase and the column packed with ODS (150 mm x 4.6 mm, 5 microns) as a fixed phase and the flow rate was 1.0 ml/min. FA was detected at 320 nm wave length. The internal standard was coumarin. The serum samples were treated by the water-boiling method. Peak of FA in serum was recognized by photodiode-array detection. FA and internal standard were separated completely under the condition described as above. FA was linear in the range of (40.16-8032 ng/ml) (r = 0.9975). The CV was less than 10%, the average recovery was 100.3%, and the limit concentration in serum was 25.1 ng/ml. PK was in accordance with open bicameral model. This method can be applied to clinical pharmacokinetic study of FA.

  18. Pharmacokinetic and pharmacodynamic study of triptolide-loaded liposome hydrogel patch under microneedles on rats with collagen-induced arthritis

    Directory of Open Access Journals (Sweden)

    Gui Chen

    2015-11-01

    Full Text Available Triptolide (TP, a major active component of Tripterygium wilfordii Hook.F. (TWHF, is used to treat rheumatoid arthritis (RA. However, it has a narrow therapeutic window due to its serious toxicities. To increase the therapeutic index, a new triptolide-loaded transdermal delivery system, named triptolide-loaded liposome hydrogel patch (TP-LHP, has been developed. In this paper, we used a micro-needle array to deliver TP-LHP to promote transdermal absorption and evaluated this treatment on the pharmacokinetics and pharmacodynamics of TP-LHP in a rat model of collagen-induced arthritis (CIA. The pharmacokinetic results showed that transdermal delivery of microneedle TP-LHP yielded plasma drug levels which fit a one-compartment open model. The relationship equation between plasma concentration and time was C=303.59×(e−0.064t−e−0.287t. The results of pharmacodynamic study demonstrated that TP-LHP treatment mitigated the degree of joint swelling and suppressed the expressions of fetal liver kinase-1, fetal liver tyrosine kinase-4 and hypoxia-inducible factor-1α in synovium. Other indicators were also reduced by TP-LHP, including hyperfunction of immune, interleukin-1β and interleukin-6 levels in serum. The therapeutic mechanism of TP-LHP might be regulation of the balance between Th1 and Th2, as well as inhibition of the expression and biological effects of vascular endothelial growth factor.

  19. Peritoneal Nebulization of Ropivacaine during Laparoscopic Cholecystectomy: Dose Finding and Pharmacokinetic Study

    Directory of Open Access Journals (Sweden)

    Massimo Allegri

    2017-01-01

    Full Text Available Background. Intraperitoneal nebulization of ropivacaine reduces postoperative pain and morphine consumption after laparoscopic surgery. The aim of this multicenter double-blind randomized controlled trial was to assess the efficacy of different doses and dose-related absorption of ropivacaine when nebulized in the peritoneal cavity during laparoscopic cholecystectomy. Methods. Patients were randomized to receive 50, 100, or 150 mg of ropivacaine 1% by peritoneal nebulization through a nebulizer. Morphine consumption, pain intensity in the abdomen, wound and shoulder, time to unassisted ambulation, discharge time, and adverse effects were collected during the first 48 hours after surgery. The pharmacokinetics of ropivacaine was evaluated using high performance liquid chromatography. Results. Nebulization of 50 mg of ropivacaine had the same effect of 100 or 150 mg in terms of postoperative morphine consumption, shoulder pain, postoperative nausea and vomiting, activity resumption, and hospital discharge timing (>0.05. Plasma concentrations did not reach toxic levels in any patient, and no significant differences were observed between groups (P>0.05. Conclusions. There is no enhancement in analgesic efficacy with higher doses of nebulized ropivacaine during laparoscopic cholecystectomy. When administered with a microvibration-based aerosol humidification system, the pharmacokinetics of ropivacaine is constant and maintains an adequate safety profile for each dosage tested.

  20. Rectal methadone in cancer patients with pain. A preliminary clinical and pharmacokinetic study.

    Science.gov (United States)

    Ripamonti, C; Zecca, E; Brunelli, C; Rizzio, E; Saita, L; Lodi, F; De Conno, F

    1995-10-01

    Cancer pain can be treated in most cases with oral analgesics. However, during their clinical history, 53% to 70% of patients will need alternative routes of opioid administration. The rectal administration of opioids is a simple alternative route for many patients. There are no data in the literature regarding the pharmacodynamics and pharmacokinetics of rectal methadone. We evaluated the analgesia, tolerability and absorption profile of methadone hydrochloride in six opioid-naive cancer patients with pain. A blood sample was collected before administration of a single dose of drug (10 mg) and then again after fixed times. At these fixed times the patients were asked about pain, nausea and drowsiness by means of a visual analogue scale of 0-100 mm (VAS). Pain relief was statistically significant as early as 30 minutes and up to eight hours after methadone administration. None of the patients reported significant side effects. The pharmacokinetics of rectal methadone showed rapid and extensive distribution phases followed by a slow elimination phase. Rectal methadone can be considered an effective analgesic therapy for patients with cancer pain for whom oral and/or parenteral opioids are not indicated or available.

  1. Preclinical pharmacokinetics, biodistribution, radiation dosimetry and acute toxicity studies required for regulatory approval of a Clinical Trial Application for a Phase I/II clinical trial of 111In-BzDTPA-pertuzumab

    International Nuclear Information System (INIS)

    Lam, Karen; Chan, Conrad; Done, Susan J.; Levine, Mark N.; Reilly, Raymond M.

    2015-01-01

    Introduction: 111 In-BzDTPA-pertuzumab is a novel imaging probe for detecting changes in HER2 expression in breast cancer (BC) caused by treatment with trastuzumab (Herceptin). Our aim was to evaluate the pharmacokinetics, normal tissue biodistribution, radiation dosimetry and acute toxicity of 111 In-BzDTPA-pertuzumab in non-tumor bearing mice in order to obtain regulatory approval to advance this agent to a first-in-humans Phase I/II clinical trial. Methods: Biodistribution and pharmacokinetic studies were performed in non-tumor bearing Balb/c mice injected i.v. with 111 In-BzDTPA-pertuzumab (2.5 MBq; 2 μg). The cumulative number of disintegrations per source organ derived from the biodistribution data was used to predict the radiation absorbed doses in humans using OLINDA/EXM software. Acute toxicity was studied at two weeks post-injection of 111 In-BzDTPA-pertuzumab (1.0 MBq, 20 μg) with comparison to control mice injected with unlabeled BzDTPA-pertuzumab (20 μg) or Sodium Chloride Injection USP. The dose of 111 In-BzDTPA-pertuzumab corresponded to 23-times the human radioactivity dose and 10-times the protein dose on a MBq/kg and mg/kg basis, respectively. Toxicity was assessed by monitoring body mass, complete blood cell count (CBC), hematocrit (Hct), hemoglobin (Hb), serum creatinine (SCr) and alanine aminotransferease (ALT) and by histopathological examination of tissues at necropsy. Results: 111 In-BzDTPA-pertuzumab exhibited a biphasic elimination from the blood with a distribution half-life (t 1/2 α) of 3.8 h and an elimination half-life (t 1/2 β) of 228.2 h. The radiopharmaceutical was distributed mainly in the blood, heart, lungs, liver, kidneys and spleen. The projected whole-body radiation absorbed dose in humans was 0.05 mSv/MBq corresponding to a total of 16.8 mSv for three separate administrations of 111 In-BzDTPA-pertuzumab (111 MBq) planned for the Phase I/II trial. There were slight changes in Hb and SCr levels associated with

  2. The distribution and elimination of Bothrops erythromelas venom labeled with 131 I after intravenous injection in mice

    International Nuclear Information System (INIS)

    Rocha, M.L.

    1999-01-01

    Pharmacokinetic studies can be used to study the systemic effects of snake venoms and to develop standard serotherapy protocols for envenomation. Bothrops erythromelas is probably responsible for most of the snakebite in Pernambuco. The objective of this study was to investigate the pharmacokinetics of B. erythromelas venom (BeV) in mice, and to evaluate the efficacy of bothropic antivenom. BeV showed bicompartmental distribution in the blood of the experimental animals. (author)

  3. The distribution and elimination of Bothrops erythromelas venom labeled with {sup 131} I after intravenous injection in mice

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, M.L. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Zoologia]. E-mail: rocha@cascavel.uefs.br

    1999-07-01

    Pharmacokinetic studies can be used to study the systemic effects of snake venoms and to develop standard serotherapy protocols for envenomation. Bothrops erythromelas is probably responsible for most of the snakebite in Pernambuco. The objective of this study was to investigate the pharmacokinetics of B. erythromelas venom (BeV) in mice, and to evaluate the efficacy of bothropic antivenom. BeV showed bicompartmental distribution in the blood of the experimental animals. (author)

  4. Validated LC-MS/MS method for the determination of 3-hydroxflavone and its glucuronide in blood and bioequivalent buffers: application to pharmacokinetic, absorption, and metabolism studies.

    Science.gov (United States)

    Xu, Beibei; Yang, Guanyi; Ge, Shufan; Yin, Taijun; Hu, Ming; Gao, Song

    2013-11-01

    The purpose of this study is to develop an UPLC-MS/MS method to quantify 3-hydroxyflavone (3-HF) and its metabolite, 3-hydroxyflavone-glucuronide (3-HFG) from biological samples. A Waters BEH C8 column was used with acetonitrile/0.1% formic acid in water as mobile phases. The mass analysis was performed in an API 5500 Qtrap mass spectrometer via multiple reaction monitoring (MRM) with positive scan mood. The one-step protein precipitation by acetonitrile was used to extract the analytes from blood. The results showed that the linear response range was 0.61-2500.00 nM for 3-HF and 0.31-2500.00 nM for 3-HFG. The intra-day variance is less than 16.5% and accuracy is in 77.7-90.6% for 3-HF and variance less than 15.9%, accuracy in 85.1-114.7% for 3-HFG. The inter-day variance is less than 20.2%, accuracy is in 110.6-114.2% for 3-HF and variance less than 15.6%, accuracy in 83.0-89.4% for 3-HFG. The analysis was done within 4.0 min. Only 10 μl of blood is needed due to the high sensitivity of this method. The validated method was successfully used to pharmacokinetic study in A/J mouse, transport study in the Caco-2 cell culture model, and glucuronidation study using mice liver and intestine microsomes. The applications revealed that this method can be used for 3-HF and 3-HFG analysis in blood as well as in bioequivalent buffers such HBSS and KPI. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Pharmacokinetic and imaging studies of the hepatobiliary agent sup(99m)Tc-pyridoxal leucine

    International Nuclear Information System (INIS)

    Sawas-Dimopoulou, C.; Chiotellis, E.; Dassiou, A.; Papanicolaou, N.; Simitzis, G.; Koutoulidis, K.; Hadzilouka-Mantaka, A.

    1978-01-01

    An investigation into the usefulness of sup(99m)Tc-pyridoxal leucine has demonstrated its advantages over 131 I-rose bengal in the diagnosis of patients with several liver and gall bladder complaints. Toxicity studies in mice, rabbits and dogs showed no histological signs of tissular lesions at doses of up to 5000 to 25,000 times the clinical dose. Visualization of the liver, gall bladder and biliary excretion into intestines was rapid. The appearance of activity into the intestines was delayed in patients with partial obstruction of the common bile duct. Insufficient diagnostic information was provided in jaundiced patients with higher levels of bilirubin (7 to 12 mg%). These patients showed reduced liver uptake with high background, and intestinal activity was not always clearly visualized in an 18 h study. At bilirubin levels higher than 12 mg% no liver uptake was usually observed, but only renal activity. 131 I-rose bengal was preferable for the differential diagnosis of obstructive jaundice in these patients. (U.K.)

  6. Poly(n-butylcyanoacrylate nanoparticles for oral delivery of quercetin: preparation, characterization, and pharmacokinetics and biodistribution studies in Wistar rats

    Directory of Open Access Journals (Sweden)

    Bagad M

    2015-06-01

    Full Text Available Mayur Bagad, Zaved Ahmed KhanMedical Biotechnology Division, School of Biosciences and Technology, VIT University, Vellore Tamil Nadu, IndiaBackground: Quercetin (QT is a potential bioflavonol and antioxidant with poor bioavailability and very low distribution in the brain. A new oral delivery system comprising of poly(n-butylcyanoacrylate nanoparticles (PBCA NPs was introduced to improve the oral bioavailability of QT and to increase its distribution in the brain. Physicochemical characteristics, in vitro release, stability in simulated gastric fluid and intestinal fluids, and pharmacokinetics and biodistribution studies of QT-PBCA NPs coated with polysorbate-80 (P-80 were investigated.Objective: This study aimed to investigate the physicochemical characteristics, in vitro release, stability in simulated gastric fluid and intestinal fluids, and pharmacokinetics and biodistribution studies of QT-PBCA NPs coated with polysorbate-80 (P-80.Results: The results showed that QT-PBCA NPs and QT-PBCA NPs coated with P-80 (QT-PBCA+P-80 had mean particle sizes of 161.1±0.44 nm and 166.6±0.33 nm respectively, and appeared spherical in shape under transmission electron microscopy. The mean entrapment efficiency was 79.86%±0.45% for QT-PBCA NPs and 74.58%±1.44% for QT-PBCA+P-80. The in vitro release of QT-PBCA NPs and QT-PBCA+P-80 showed an initial burst release followed by a sustained release when compared to free QT. The relative bioavailability of QT-PBCA NPs and QT-PBCA+P-80 enhanced QT bioavailability by 2.38- and 4.93-fold respectively, when compared to free QT. The biodistribution study in rats showed that a higher concentration of QT was detected in the brain after the NPs were coated with P-80.Conclusion: This study indicates that PBCA NPs coated with P-80 can be potential drug carriers for poorly water-soluble drugs. These NPs were observed to improve the drugs’ oral bioavailability and enhance their transport to the brain

  7. Pharmacokinetic properties of radiolabeled mutant Interleukin-2v: a PET imaging study.

    Science.gov (United States)

    Hartimath, Siddesh V; Manuelli, Valeria; Zijlma, Rolf; Signore, Alberto; Nayak, Tapan K; Freimoser-Grundschober, Anne; Klein, Christian; Dierckx, Rudi A J O; de Vries, Erik F J

    2018-01-23

    Interleukin-2 (IL2) is a cytokine that can stimulate cytotoxic immune cells to attack infected and malignant cells. Unfortunately, IL2 can also cause serious immune-related toxicity. Recently, a mutant of IL2 (IL2v) with abolished CD25 binding, increased plasma half-life and less toxicity was engineered. Unlike wild-type IL2 (wt-IL2), mutant IL2v does not bind to the α-subunit (CD25) of the high affinity IL2αβγ receptor, but only to its β and γ subunit. Here, we investigated the biological properties of IL2v and compared with the wt-IL2 using fluorine-18 and PET. [ 18 F]FB-IL2v binds specifically to IL2 receptors (IL2R) on activated human peripheral blood monocytes (hPBMCs) and is cleared mainly by the kidneys (Balb/c mice). [ 18 F]FB-IL2v PET studies in SCID mice injected with hPBMCs revealed high uptake in the implant (0.85 ± 0.15 SUV), which was significantly reduced after pretreatment with wt-IL2 or mutant IL2v (SUV 0.26 ± 0.1 and 0.46 ± 0.1, p FB-IL2v to IL2R was reversible. The volume of distribution (V T ) and the non-displaceable binding potential (BP nd ) of mutant [ 18 F]FB-IL2v in the implant were approximately 3 times lower than those of wild-type [ 18 F]FB-IL2 ( p FB-IL2v in the implant ( p FB-IL2 binds stronger to IL2R and has faster kinetics than [18F]FB-IL2v, which makes it less suitable as a therapeutic drug. [ 18 F]FB-IL2v, on the other hand, seems to have better properties for use as a therapeutic drug.

  8. Characterization of the disposition of fostamatinib in Japanese subjects including pharmacokinetic assessment in dry blood spots: results from two phase I clinical studies.

    Science.gov (United States)

    Martin, Paul; Cheung, S Y Amy; Yen, Mark; Han, David; Gillen, Michael

    2016-01-01

    The aims of the present study were to characterize the pharmacokinetics of fostamatinib in two phase I studies in healthy Japanese subjects after single- and multiple-dose administration, and to evaluate the utility of dried blood spot (DBS) sampling. In study A, 40 Japanese and 16 white subjects were randomized in a double-blind parallel group study consisting of seven cohorts, which received either placebo or a fostamatinib dose between 50 and 200 mg after single and multiple dosing. Pharmacokinetics of R406 (active metabolite of fostamatinib) in plasma and urine was assessed, and safety was intensively monitored. Study B was an open-label study that assessed fostamatinib 100 and 200 mg in 24 Japanese subjects. In addition to plasma and urine sampling (as for study A), pharmacokinetics was also assessed in blood. Mean maximum plasma concentration (C max) and area under total plasma concentration–time curve (AUC) increased with increasing dose in Japanese subjects. Steady state was achieved in 5–7 days for all doses. C max and AUC were both higher in Japanese subjects administered a 150-mg single dose than in white subjects. This difference was maintained for steady state exposure by day 10. Overall, R406 blood concentrations were consistent and ∼2.5-fold higher than in plasma. Minimal (blood cells, and DBS sampling was a useful method for assessing R406 pharmacokinetics.

  9. Leflunomide in dialysis patients with rheumatoid arthritis--a pharmacokinetic study.

    Science.gov (United States)

    Bergner, Raoul; Peters, Lena; Schmitt, Verena; Löffler, Christian

    2013-02-01

    Pharmacokinetic data of disease modifying antirheumatic drugs during hemodialysis are limited to sulfasalazine, methotrexate, and cyclosporine. Only respective anecdotal data have been reported on leflunomide. We repeatedly measured teriflunomide (A77-1726), the active metabolite of leflunomide, during standard hemodialysis sessions and calculated teriflunomide clearances in five patients with rheumatoid arthritis (RA) and end-stage renal disease. The calculated teriflunomide clearances during a standardized dialysis session of 3-4.5 h at a blood flow rate of 160-300 ml/min were between 0 and 4.3 ml/min, the mean clearances of the total dialysis ranged between 1.1 and 3.4 ml/min. Total amount of teriflunomide removed was 5.8-8.8 μg per dialysis session. Dialytic removal of the active metabolite of leflunomide, teriflunomide (A77-1726), is negligible. Leflunomide can be used for RA patients on chronic dialysis without any dosage modification.

  10. Effect of Co-Administration of Rivaroxaban and Clopidogrel on Bleeding Time, Pharmacodynamics and Pharmacokinetics: A Phase I Study

    Directory of Open Access Journals (Sweden)

    Michael Becka

    2012-02-01

    Full Text Available Dual antiplatelet therapy with acetylsalicylic acid and a thienopyridine, such as clopidogrel, is effective for the secondary prevention of cardiovascular events in patients with acute coronary syndrome, but there is still a substantial residual risk of recurrence. Although anticoagulant therapy with a vitamin K antagonist (e.g. warfarin in conjunction with antiplatelet therapy has been shown to reduce the risk of cardiovascular events, the rates of bleeding were increased with these combination therapies; hence, triple therapy with warfarin is currently only recommended in patients at low risk of bleeding. In addition, there are other limitations associated with vitamin K antagonist therapy, including the need for routine coagulation monitoring and dose adjustment to maintain the treatment within the therapeutic range. Rivaroxaban is an oral, direct Factor Xa inhibitor; in clinical practice, it is likely that rivaroxaban will be given to patients who also receive antiplatelet therapy, such as clopidogrel. This randomized, non-blinded, three-way crossover study investigated the effect of rivaroxaban on bleeding time when co­administered with clopidogrel. In addition, the influence of clopidogrel on the safety, tolerability, pharmacodynamics and pharmacokinetics of rivaroxaban was investigated. Of 27 healthy male subjects who received a single 300 mg dose of clopidogrel, 14 were identified as clopidogrel responders and were then randomized to the following three treatments: (A two doses of clopidogrel on two consecutive days (300 mg on day 1; 75 mg on day 2; (B one dose of rivaroxaban (15 mg; or (C a combination of treatments A and B (rivaroxaban given on day 2. All treatments were well tolerated. Bleeding time with co­administration of rivaroxaban and clopidogrel was significantly prolonged in four subjects, compared with either drug alone: combination treatment increased the overall least squares-means to 3.77 times baseline (90% confidence

  11. Human volunteer studies with non-pharmaceutical chemicals: metabolism and pharmacokinetic studies.

    Science.gov (United States)

    Wilks, M F; Woollen, B H

    1994-06-01

    1. Human volunteer studies are an essential part of drug development but their use in the area of non-pharmaceutical chemicals has so far been very limited. Such studies can have considerable value in the assessment and improvement of the safe use of chemicals. 2. Once metabolic pathways and target metabolites have been identified in volunteers this information can be used in studies in the workplace or in the general population. Studies should be performed selectively only if there is both a toxic hazard and a significant exposure potential. In addition, they should only be carried out if the required information cannot be obtained in any other way. 3. Volunteer studies with non-pharmaceuticals have become increasingly acceptable in the light of established international guidelines, no-fault compensation, improvements in study design and technical developments which allow the use of very low dose levels. The final decision on whether to carry out a study must always rest with an independent ethical committee. 4. The practical aspects of the study should be specified in a detailed protocol conforming with the principles of good clinical practice. The safety of volunteers must be of paramount concern throughout. Depending on the nature of the chemical and the study, it may be advisable to carry out studies in a clinical facility where equipment is available for the treatment of any emergencies that might occur. 5. Numerous investigators have now shown that human volunteer studies are ethically acceptable, practicable and yield important information. The risk to volunteers is minimal and this approach can lead to an improved foundation for occupational hygiene standards, more accurate risk assessment and thus better protection of the workforce and the general population.

  12. A Pharmacokinetics, Efficacy, and Safety Study of Gadoterate Meglumine in Pediatric Subjects Aged Younger Than 2 Years.

    Science.gov (United States)

    Scala, Mario; Koob, Meriam; de Buttet, Sophie; Bourrinet, Philippe; Felices, Mathieu; Jurkiewicz, Elzbieta

    2018-02-01

    The primary objective of this study was to investigate the pharmacokinetic profile of gadoterate meglumine in pediatric patients younger than 2 years; the secondary objectives were to document its efficacy and safety. This was a Phase IV open-label, prospective study conducted in 9 centers (4 countries). Forty-five patients younger than 2 years with normal estimated glomerular filtration rate and scheduled to undergo routine gadolinium-enhanced magnetic resonance imaging (MRI) of any organ were included and received a single intravenous injection of gadoterate meglumine (0.1 mmol/kg). To perform the population pharmacokinetics analysis, 3 blood samples per subject were drawn during 3 time windows at time points allocated by randomization. Gadoterate meglumine concentrations were best fitted using a 2-compartmental model with linear elimination from central compartment. The median total clearance adjusted to body weight was estimated at 0.06 L/h per kg and increased with estimated glomerular filtration rate according to a power model. The median volume of distribution at steady state (Vss) adjusted to body weight was estimated at 0.047 L/kg. Estimated median terminal half-life (t1/2β) was 1.35 h, and the median systemic exposure (area under the curve) was 1591 μmol h/L. Efficacy was assessed by comparing precontrast +postcontrast images to precontrast images in a subset of 28 subjects who underwent an MRI examination of brain, spine, and associated tissues. A total of 28 lesions were identified and analyzed in 15 subjects with precontrast images versus 30 lesions in 16 subjects with precontrast + postcontrast images. Lesion visualization was improved with a mean (SD) increase in scores at subject level of 0.7 (1.0) for lesion border delineation, 0.9 (1.6) for internal morphology, and 3.1 (3.2) for contrast enhancement. Twenty-six adverse events occurred postinjection in 13 subjects (28.9%), including 3 serious reported in 1 subject (2.2%). One subject (2

  13. A study of potential pharmacokinetic and pharmacodynamic interactions between dextromethorphan/quinidine and memantine in healthy volunteers.

    Science.gov (United States)

    Pope, Laura E; Schoedel, Kerri A; Bartlett, Cynthia; Sellers, Edward M

    2012-08-01

    Dextromethorphan/quinidine (DMQ) is the first agent indicated for the treatment of pseudobulbar affect. Dextromethorphan, the active ingredient, is a low-affinity, uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist. This study evaluated the potential for a drug-drug interaction (DDI) of DMQ with memantine, which is also an NMDA receptor antagonist. This open-label, randomized, parallel-group study enrolled healthy adults who were randomized into one of two treatment groups. Group 1 subjects were administered memantine at a starting dose of 5 mg once daily, which was titrated over a 3-week period to a dose of 10 mg twice daily (every 12 hours) and continued for another 11 days to attain steady state; DMQ 30 mg (dextromethorphan 30 mg/quinidine 30 mg) every 12 hours was then added for a further 8 days. Group 2 subjects received DMQ 30 mg every 12 hours for 8 days to attain steady state; memantine was then added, titrated on the same schedule as in group 1, and continued at 10 mg every 12 hours for an additional 11 days. Pharmacokinetic blood sampling was performed to assess the primary endpoints of the 90% confidence intervals (CIs) for the geometric mean ratios of the areas under the plasma concentration-time curves (AUCs) for memantine, dextromethorphan, dextrorphan - the dextromethorphan metabolite - and quinidine during concomitant therapy versus monotherapy. Safety/tolerability and pharmacodynamic variables were also assessed. A total of 52 subjects were randomized. In both group 1 (n = 23) and group 2 (n = 29), the 90% CIs for the ratios of the AUCs during concomitant therapy versus monotherapy were within the predefined range to indicate similarity (0.8-1.25) for memantine, dextromethorphan and dextrorphan, indicating no pharmacokinetic DDI. The 90% CI for the AUC ratio for quinidine was slightly above the predefined range; however, the mean AUC increased by only 25%. In both groups, incidence of adverse events was similar, and pharmacodynamic

  14. Population pharmacokinetic study of benznidazole in pediatric Chagas disease suggests efficacy despite lower plasma concentrations than in adults.

    Directory of Open Access Journals (Sweden)

    Jaime Altcheh

    2014-05-01

    Full Text Available Chagas disease, caused by the parasite Trypanosoma cruzi, can lead to long term cardiac morbidity. Treatment of children with benznidazole is effective, but no pediatric pharmacokinetics data are available and clinical pharmacology information on the drug is scarce.Prospective population pharmacokinetic (PK cohort study in children 2-12 years old with Chagas disease treated with oral benznidazole 5-8 mg/kg/day BID for 60 days. (clinicaltrials.gov #NCT00699387.Forty children were enrolled in the study. Mean age was 7.3 years. A total of 117 samples were obtained from 38 patients for PK analysis. A one compartment model best fit the data. Weight-corrected clearance rate (CL/F showed a good correlation with age, with younger patients having a significantly higher CL/F than older children and adults. Simulated median steady-state benznidazole concentrations, based on model parameters, were lower for children in our study than for adults and lowest for children under 7 years of age. Treatment was efficacious in the 37 patients who completed the treatment course, and well tolerated, with few, and mild, adverse drug reactions (ADRs.Observed benznidazole plasma concentrations in children were markedly lower than those previously reported in adults (treated with comparable mg/kg doses, possibly due to a higher CL/F in smaller children. These lower blood concentrations were nevertheless associated to a high therapeutic response in our cohort. Unlike adults, children have few adverse reactions to the drug, suggesting that there may be a direct correlation between drug concentrations and incidence of ADRs. Our results suggest that studies with lower doses in adults may be warranted.ClinicalTrials.gov NCT00699387.

  15. Simultaneous determination of five components in rat plasma by UPLC-MS/MS and its application to a comparative pharmacokinetic study in Baihe Zhimu Tang and Zhimu extract.

    Science.gov (United States)

    Li, Guolong; Tang, Zhishu; Yang, Jie; Duan, Jinao; Qian, Dawei; Guo, Jianming; Zhu, Zhenhua; Liu, Hongbo

    2015-04-15

    Baihe Zhimu Tang (BZT) is a famous traditional Chinese medicine recipe to treat dry coughing due to yin deficiency and for moisturizing the lungs. Zhimu is an essential ingredient in BZT used to treat inflammation, fever and diabetes. The most important active components in Zhimu are flavonoids such as neomangiferin, mangiferin, and steroid saponins (e.g., timosaponin BII, anemarsaponin BIII, timosaponin AIII). The aim of this study was to compare the pharmacokinetics of mangiferin, neomangiferin, timosaponin BII, anemarsaponin BIII and timosaponin AIII in rat plasma after oral administration of BZT and Zhimu extract (ZME). A sensitive, reliable and robust LC-MS/MS method to simultaneously determine steroid saponins and flavonoids in rat plasma was successfully validated. Significant differences (p < 0.05) were found in the pharmacokinetic parameters of timosaponin BII, anemarsaponin BIII and timosaponin AIII between BZT and ZME. It was surmised that formula compatibility could significantly influence the pharmacokinetics of BZT and our study is the first to study the administration of BZT based on pharmacokinetic studies.

  16. Luteolin-loaded solid lipid nanoparticles synthesis, characterization, & improvement of bioavailability, pharmacokinetics in vitro and vivo studies

    Science.gov (United States)

    Dang, Hao; Meng, Murtaza Hasan Weiwei; Zhao, Haiwei; Iqbal, Javed; Dai, Rongji; Deng, Yulin; Lv, Fang

    2014-04-01

    Luteolin (LU, 5,7,3',4'-tetrahydroxyflavone) most active compound in Chinese herbal flavones has been acting as a antimicrobial, anti-inflammatory, anti-cancer, and antimutagen. However, its poor bioavailability, hydrophobicity, and pharmacokinetics restrict clinical application. Here in this study, LU-loaded solid lipid nanoparticles have been prepared by hot-microemulsion ultrasonic technique to improve the bioavailability & pharmacokinetics of compound. LU-loaded solid lipid nanoparticle size was confirmed by particle size analyzer with range from 47 to 118 nm, having zepta potential -9.2 mV and polydisperse index 0.247, respectively. Round-shaped SLNPs were obtained by using transmission electron microscope, and encapsulation efficiency 74.80 % was calculated by using HPLC. Both in vitro and vivo studies, LC-MS/MS technique was used for quantification of Luteolin in rat. The T max value of drug with LU-SLNs after the administration was Ten times shorter than pure Luteolin suspension administration. C max value of drug after the administration of LU-SLNs was five times higher than obtained with native drug suspension. Luteolin with SLNs has increased the half-life approximately up to 2 h. Distribution and clearance of drug with SLNs were significantly decreased by 2.16-10.57 fold, respectively. In the end, the relative bioavailability of SLNs has improved about 4.89 compared to Luteolin with SLNs. From this study, it can be concluded that LU-SLNs have not only great potential for improving solubility but also increased the drug concentration in plasma. Furthermore, use of LC-MS/MS for quantification of LU-SLNs in rat plasma is reliable and of therapeutic usefulness, especially for neurodegenerative and cancerous disorders in humans.

  17. A study of dose-proportionality in the pharmacokinetics of the oral direct renin inhibitor aliskiren in healthy subjects.

    Science.gov (United States)

    Limoges, D; Dieterich, H A; Yeh, C-M; Vaidyanathan, S; Howard, D; Dole, W P

    2008-05-01

    To evaluate the dose-proportionality of the pharmacokinetics of aliskiren, the first in a new class of orally active direct renin inhibitors approved for the treatment of hypertension. This was an open-label, single-center, single-dose, randomized, 4-period crossover study. Following a 21-day screening period, 32 healthy male or female subjects (ages 18 - 45 years) were randomized to 1 of 4 aliskiren dosing sequence groups (8 subjects per group): 75, 150, 300 and 600 mg. Blood samples were obtained for determination of plasma aliskiren concentrations (HPLC/MS/MS) for 96 h post dose. Log-transformed pharmacokinetic parameters AUC and C(max) were analyzed to determine dose-proportionality using the power model, parameter = A*(Dose)(beta), where A = intercept and beta = dose-proportionality coefficient. The predefined dose-proportionality criteria over the dose range 75 â 600 mg were 90% confidence intervals (CI) for beta contained within the range 0.89 - 1.11. AUC and Cmax values increased with increasing doses of aliskiren. Both AUC and C(max) were associated with high variability (coefficient of variation 55 - 64% for AUC and 59 - 117% for C(max)). The estimated proportionality coefficients (beta) for AUC(0-infiniti), AUC(0-t) and C(max) were 1.18 (90% CI 1.10, 1.25), 1.29 (90% CI 1.22, 1.36) and 1.42 (90% CI 1.31, 1.52), respectively. Dose-proportionality was, therefore, not demonstrated across the entire 8-fold dose range. For the clinical dose range of 150 â 300 mg, increases of 2.3- and 2.6-fold were observed for AUC and C(max), respectively. All doses of aliskiren were well tolerated. Exposure to aliskiren was greater than proportional over the dose range of 75 - 600 mg. Over the therapeutic dose range of 150 â 300 mg approved for the treatment of hypertension, AUC and Cmax increased by 2.3- and 2.6-fold, respectively. The pharmacokinetics of aliskiren show relatively high intersubject variability.

  18. Radioautographic DNA synthesis study on mice Mus musculus gingival epithelium

    International Nuclear Information System (INIS)

    Silveira Tarelho, Z.V. da; Hetem, S.

    1984-01-01

    The DNA-synthetizing cells frequency in the gingival epithelium basal layer of the first lower molar region in young and adult mice were studied. The 3H-thymidine and radioautography were used. The labeled cells frequency was determined by calculating their proportions. The data were statiscally analysed. (M.A.C.) [pt

  19. Multiple-dose pharmacokinetic study of proguanil and cycloguanil following 12-hourly administration of 100 mg proguanil hydrochloride.

    Science.gov (United States)

    Jamaludin, A; Mohamad, M; Navaratnam, V; Yeoh, P Y; Wernsdorfer, W H

    1990-09-01

    A pharmacokinetic study with 12-hourly doses of 100 mg proguanil hydrochloride over 15 days has been conducted in six adult male Malaysian volunteers. Steady state for proguanil was established after the fourth dose on Day 2, for the active metabolite cycloguanil as from Day 3 inclusive. The steady state mean peak concentration of proguanil was 1201.6 +/- 132.4 nmol/l, the mean trough concentration 650.0 +/- 58.1 nmol/l. The corresponding values for cycloguanil were 317.0 +/- 44.4 nmol/l (mean peak) and 230.8 +/- 35.1 nmol/l (mean trough). The profiles and peak/trough ratios of proguanil and cycloguanil with 12-hourly dosing offer better prospects for protection against malaria than those obtained with 24-hourly doses of 200 mg proguanil hydrochloride, the current routine in malaria chemoprophylaxis.

  20. Pharmacokinetics and bioequivalence study of a fixed dose combination of rabeprazole and itopride in healthy Indian volunteers.

    Science.gov (United States)

    Sahoo, Bijay Kumar; Das, Ayan; Agarwal, Sangita; Bhaumik, Uttam; Bose, Anirbandeep; Ghosh, Debotri; Roy, Bikash; Pal, Tapan Kumar

    2009-01-01

    The aim of the present study was to compare the pharmacokinetics of rabeprazole (CAS 117976-89-3) and itopride (CAS 122898-67-3) after oral administration of a rabeprazole (20 mg)-itopride (150 mg) fixed dose combination (FDC) in healthy human volunteers. The bioequivalence of two formulations (test and reference) was determined in 12 healthy Indian male volunteers (age: 25.25 +/- 4.69 years; weight: 60.50 +/- 5.04 kg) in a randomized, single-dose, two-period, two-treatment crossover study. Both formulations were administered orally as a single dose, with the treatments separated by a washout period of 1 week. Rabeprazole and itopride plasma levels were determined by a validated HPLC method using UV detection. The formulations were compared using the pharmacokinetic parameters area under the plasma concentration-time curve (AUC(0-t)), area under the plasma concentration-time curve from zero to infinity (AUC(0-infinity)) and peak plasma concentration (Cmax). General linear model (GLM) procedures were used in which sources of variation were subject, treatment and period. The results indicated that there were no statistically significant differences (P > 0.05) between the logarithmically transformed AUC(0-infinity) and Cmax values between test and reference formulation. The 90% confidence interval for the ratio of the logarithmically transformed AUC(0-t), AUC(0-infinity) and Cmax were within the bioequivalence limits of 0.8-1.25 and the relative bioavailability of rabeprazole and itopride test and reference formulations was 98.24 and 93.65%, respectively.

  1. Evaluation of Isolated Fractions of Aloe vera Gel Materials on Indinavir Pharmacokinetics: In vitro and in vivo Studies.

    Science.gov (United States)

    Wallis, Lonette; Malan, Maides; Gouws, Chrisna; Steyn, Dewald; Ellis, Suria; Abay, Efrem; Wiesner, Lubbe; Otto, Daniel P; Hamman, Josias

    2016-01-01

    Aloe vera is a plant with a long history of traditional medicinal use and is consumed in different products, sometimes in conjunction with prescribed medicines. A. vera gel has shown the ability to modulate drug absorption in vitro. The aim of this study was to fractionate the precipitated polysaccharide component of A. vera gel based on molecular weight and to compare their interactions with indinavir pharmacokinetics. Crude polysaccharides were precipitated from a solution of A. vera gel and was fractionated by means of centrifugal filtration through membranes with different molecular weight cut-off values (i.e. 300 KDa, 100 KDa and 30 KDa). Marker molecules were quantified in the aloe leaf materials by means of nuclear magnetic resonance spectroscopy and the average molecular weight was determined by means of gel filtration chromatography linked to multi-angle-laser-light scattering and refractive index detection. The effect of the aloe leaf materials on the transepithelial electrical resistance (TEER) of Caco-2 cell monolayers as well as indinavir metabolism in LS180 cells was measured. The bioavailability of indinavir in the presence and absence of the aloe leaf materials was determined in Sprague-Dawley rats. All the aloe leaf materials investigated in this study reduced the TEER of Caco-2 cell monolayers, inhibited indinavir metabolism in LS 180 cells to different extents and changed the bioavailability parameters of indinavir in rats compared to that of indinavir alone. These indinavir pharmacokinetic modulation effects were not dependent on the presence of aloverose and also not on the average molecular weight of the isolated fractions.

  2. Pharmacokinetic study of isocorynoxeine metabolites mediated by cytochrome P450 enzymes in rat and human liver microsomes.

    Science.gov (United States)

    Zhao, Lizhu; Zang, Bin; Qi, Wen; Chen, Fangfang; Wang, Haibo; Kano, Yoshihiro; Yuan, Dan

    2016-06-01

    Isocorynoxeine (ICN) is one of the major bioactive tetracyclic oxindole alkaloids found in Uncaria rhynchophylla (Miq.) Jacks. that is widely used for the treatment of hypertension, vascular dementia, and stroke. The present study was undertaken to assess the plasma pharmacokinetic characteristics of major ICN metabolites, and the role of simulated gastric and intestinal fluid (SGF and SIF), human and rat liver microsomes (HLMs and RLMs), and seven recombinant human CYP enzymes in the major metabolic pathway of ICN. A rapid, sensitive and accurate UHPLC/Q-TOF MS method was validated for the simultaneous determination of ICN and its seven metabolites in rat plasma after oral administration of ICN at 40mg/kg. It was found that 18.19-dehydrocorynoxinic acid (DCA) and 5-oxoisocorynoxeinic acid (5-O-ICA) were both key and predominant metabolites, rather than ICN itself, due to the rapid and extensive metabolism of ICN in vivo. The further study indicated that ICN was mainly metabolized in human or rat liver, and CYPs 2C19, 3A4 and 2D6 were the major enzymes responsible for the biotransformation of ICN to DCA and 5-O-ICA in human. These findings are of significance in understanding of the pharmacokinetic nature of tetracyclic oxindole alkaloids, and provide helpful information for the clinical co-administration of the herbal preparations containing U. rhynchophylla with antihypertensive drugs that are mainly metabolized by CYP3A4 and CYP2C19. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Pharmacokinetics, Tissue Distribution and Therapeutic Effect of Cationic Thermosensitive Liposomal Doxorubicin Upon Mild Hyperthermia

    OpenAIRE

    Dicheva, Bilyana M.; Seynhaeve, Ann L. B.; Soulie, Thomas; Eggermont, Alexander M. M.; ten Hagen, Timo L. M.; Koning, Gerben A.

    2015-01-01

    textabstractPurpose: To evaluate pharmacokinetic profile, biodistribution and therapeutic effect of cationic thermosensitive liposomes (CTSL) encapsulating doxorubicin (Dox) upon mild hyperthermia (HT). Methods: Non-targeted thermosensitive liposomes (TSL) and CTSL were developed, loaded with Dox and characterized. Blood kinetics and biodistribution of Dox-TSL and Dox-CTSL were followed in B16BL6 tumor bearing mice upon normothermia (NT) or initial hyperthermia conditions. Efficacy study in B...

  4. Exploring venlafaxine pharmacokinetic variability with a phenotyping approach, a multicentric french-swiss study (MARVEL study).

    Science.gov (United States)

    Lloret-Linares, Célia; Daali, Youssef; Chevret, Sylvie; Nieto, Isabelle; Molière, Fanny; Courtet, Philippe; Galtier, Florence; Richieri, Raphaëlle-Marie; Morange, Sophie; Llorca, Pierre-Michel; El-Hage, Wissam; Desmidt, Thomas; Haesebaert, Frédéric; Vignaud, Philippe; Holtzmann, Jerôme; Cracowski, Jean-Luc; Leboyer, Marion; Yrondi, Antoine; Calvas, Fabienne; Yon, Liova; Le Corvoisier, Philippe; Doumy, Olivier; Heron, Kyle; Montange, Damien; Davani, Siamak; Déglon, Julien; Besson, Marie; Desmeules, Jules; Haffen, Emmanuel; Bellivier, Frank

    2017-11-07

    It is well known that the standard doses of a given drug may not have equivalent effects in all patients. To date, the management of depression remains mainly empirical and often poorly evaluated. The development of a personalized medicine in psychiatry may reduce treatment failure, intolerance or resistance, and hence the burden and costs of mood depressive disorders. The Geneva Cocktail Phenotypic approach presents several advantages including the "in vivo" measure of different cytochromes and transporter P-gp activities, their simultaneous determination in a single test, avoiding the influence of variability over time on phenotyping results, the administration of low dose substrates, a limited sampling strategy with an analytical method developed on DBS analysis. The goal of this project is to explore the relationship between the activity of drug-metabolizing enzymes (DME), assessed by a phenotypic approach, and the concentrations of Venlafaxine (VLX) + O-demethyl-venlafaxine (ODV), the efficacy and tolerance of VLX. This study is a multicentre prospective non-randomized open trial. Eligible patients present a major depressive episode, MADRS over or equal to 20, treatment with VLX regardless of the dose during at least 4 weeks. The Phenotype Visit includes VLX and ODV concentration measurement. Following the oral absorption of low doses of omeprazole, midazolam, dextromethorphan, and fexofenadine, drug metabolizing enzymes activity is assessed by specific metabolite/probe concentration ratios from a sample taken 2 h after cocktail administration for CYP2C19, CYP3A4, CYP2D6; and by the determination of the limited area under the curve from the capillary blood samples taken 2-3 and 6 h after cocktail administration for CYP2C19 and P-gp. Two follow-up visits will take place between 25 and 40 days and 50-70 days after inclusion. They include assessment of efficacy, tolerance and observance. Eleven french centres are involved in recruitment, expected to be

  5. Comparative bioavailability and pharmacokinetics of two oral formulations of flurbiprofen: a single-dose, randomized, open-label, two-period, crossover study in Pakistani subjects.

    Science.gov (United States)

    Qayyum, Aisha; Najmi, Muzammil Hasan; Abbas, Mateen

    2013-11-01

    Comparative bioavailability studies are conducted to establish the bioequivalence of generic formulation with that of branded reference formulation, providing confidence to clinicians to use these products interchangeably. This study was carried out to compare a locally manufactured formulation of flurbiprofen with that of a branded product. Twenty two healthy male adults received a single dose of flurbiprofen (100mg) either generic or branded product according to randomization scheme on each of 2 periods. Blood samples were collected and plasma flurbiprofen concentration was determined by a validated HPLC method. Pharmacokinetic parameters like AUC(0-t), AUC(0-oo), Cmax, Tmax, t½, Vd and clearance were determined. The 90% CI for the ratio of geometric means of test to reference product's pharmacokinetic variables was calculated. Pharmacokinetic parameters for two formulations were comparable. Ratio of means of AUC(0-24), AUC(0-oo) and Cmax for test to reference products and 90% CI for these ratios were within the acceptable range. The p-values calculated by TOST were much less than the specified value (p-0.05). ANOVA gave p-values which were more than the specified value (p-0.05) for sequence, subject, period and formulation. Test formulation of flurbiprofen (tablet Flurso) was found to meet the criteria for bioequivalence to branded product (tablet Ansaid) based on pharmacokinetic parameters.

  6. PET Studies of d-Methamphetamine Pharmacokinetics in Primates: Comparison with l-Methamphetamine and (—)-Cocaine

    Science.gov (United States)

    Fowler, Joanna S.; Kroll, Carsten; Ferrieri, Richard; Alexoff, David; Logan, Jean; Dewey, Stephen L.; Schiffer, Wynne; Schlyer, David; Carter, Pauline; King, Payton; Shea, Colleen; Xu, Youwen; Muench, Lisa; Benveniste, Helene; Vaska, Paul; Volkow, Nora D.

    2009-01-01

    The methamphetamine molecule has a chiral center and exists as 2 enantiomers, d-methamphetamine (the more active enantiomer) and l-methamphetamine (the less active enantiomer). d-Methamphetamine is associated with more intense stimulant effects and higher abuse liability. The objective of this study was to measure the pharmacokinetics of d-methamphetamine for comparison with both l-methamphetamine and (—)-cocaine in the baboon brain and peripheral organs and to assess the saturability and pharmacologic specificity of binding. Methods d- and l-methamphetamine and (—)-cocaine were labeled with 11C via alkylation of the norprecursors with 11C-methyl iodide using literature methods. Six different baboons were studied in 11 PET sessions at which 2 radiotracer injections were administered 2–3 h apart to determine the distribution and kinetics of 11C-d-methamphetamine in brain and peripheral organs. Saturability and pharmacologic specificity were assessed using pretreatment with d-methamphetamine, methylphenidate, and tetrabenazine. 11C-d-Methamphetamine pharmacokinetics were compared with 11C-l-methamphetamine and 11C-(—)-cocaine in both brain and peripheral organs in the same animal. Results 11C-d- and l-methamphetamine both showed high uptake and widespread distribution in the brain. Pharmacokinetics did not differ between enantiomers, and the cerebellum peaked earlier and cleared more quickly than the striatum for both. 11C-d-Methamphetamine distribution volume ratio was not substantially affected by pretreatment with methamphetamine, methylphenidate, or tetrabenazine. Both enantiomers showed rapid, high uptake and clearance in the heart and lungs and slower uptake and clearance in the liver and kidneys. A comparison of 11C-d-methamphetamine and 11C-(—)-cocaine showed that 11C-d-methamphetamine peaked later in the brain than did 11C-(—)-cocaine and cleared more slowly. The 2 drugs showed similar behavior in all peripheral organs examined except the kidneys

  7. Plasma and CSF pharmacokinetics of meropenem in neonates and young infants: results from the NeoMero studies.

    Science.gov (United States)

    Germovsek, Eva; Lutsar, Irja; Kipper, Karin; Karlsson, Mats O; Planche, Tim; Chazallon, Corine; Meyer, Laurence; Trafojer, Ursula M T; Metsvaht, Tuuli; Fournier, Isabelle; Sharland, Mike; Heath, Paul; Standing, Joseph F

    2018-04-19

    Sepsis and bacterial meningitis are major causes of mortality and morbidity in neonates and infants. Meropenem, a broad-spectrum antibiotic, is not licensed for use in neonates and infants below 3 months of age and sufficient information on its plasma and CSF disposition and dosing in neonates and infants is lacking. To determine plasma and CSF pharmacokinetics of meropenem in neonates and young infants and the link between pharmacokinetics and clinical outcomes in babies with late-onset sepsis (LOS). Data were collected in two recently conducted studies, i.e. NeoMero-1 (neonatal LOS) and NeoMero-2 (neonatal meningitis). Optimally timed plasma samples (n = 401) from 167 patients and opportunistic CSF samples (n = 78) from 56 patients were analysed. A one-compartment model with allometric scaling and fixed maturation gave adequate fit to both plasma and CSF data; the CL and volume (standardized to 70 kg) were 16.7 (95% CI 14.7, 18.9) L/h and 38.6 (95% CI 34.9, 43.4) L, respectively. CSF penetration was low (8%), but rose with increasing CSF protein, with 40% penetration predicted at a protein concentration of 6 g/L. Increased infusion time improved plasma target attainment, but lowered CSF concentrations. For 24 patients with culture-proven Gram-negative LOS, pharmacodynamic target attainment was similar regardless of the test-of-cure visit outcome. Simulations showed that longer infusions increase plasma PTA but decrease CSF PTA. CSF penetration is worsened with long infusions so increasing dose frequency to achieve therapeutic targets should be considered.

  8. Safety, pharmacokinetic, and efficacy studies of oral DB868 in a first stage vervet monkey model of human African trypanosomiasis.

    Directory of Open Access Journals (Sweden)

    John K Thuita

    Full Text Available There are no oral drugs for human African trypanosomiasis (HAT, sleeping sickness. A successful oral drug would have the potential to reduce or eliminate the need for patient hospitalization, thus reducing healthcare costs of HAT. The development of oral medications is a key objective of the Consortium for Parasitic Drug Development (CPDD. In this study, we investigated the safety, pharmacokinetics, and efficacy of a new orally administered CPDD diamidine prodrug, 2,5-bis[5-(N-methoxyamidino-2-pyridyl]furan (DB868; CPD-007-10, in the vervet monkey model of first stage HAT. DB868 was well tolerated at a dose up to 30 mg/kg/day for 10 days, a cumulative dose of 300 mg/kg. Mean plasma levels of biomarkers indicative of liver injury (alanine aminotransferase, aspartate aminotransferase were not significantly altered by drug administration. In addition, no kidney-mediated alterations in creatinine and urea concentrations were detected. Pharmacokinetic analysis of plasma confirmed that DB868 was orally available and was converted to the active compound DB829 in both uninfected and infected monkeys. Treatment of infected monkeys with DB868 began 7 days post-infection. In the infected monkeys, DB829 attained a median C(max (dosing regimen that was 12-fold (3 mg/kg/day for 7 days, 15-fold (10 mg/kg/day for 7 days, and 31-fold (20 mg/kg/day for 5 days greater than the IC50 (14 nmol/L against T. b. rhodesiense STIB900. DB868 cured all infected monkeys, even at the lowest dose tested. In conclusion, oral DB868 cured monkeys with first stage HAT at a cumulative dose 14-fold lower than the maximum tolerated dose and should be considered a lead preclinical candidate in efforts to develop a safe, short course (5-7 days, oral regimen for first stage HAT.

  9. Influence of scan duration on the estimation of pharmacokinetic parameters for breast lesions: a study based on CAIPIRINHA-Dixon-TWIST-VIBE technique

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Wen; Zhao, Bin; Wang, Guangbin; Wang, Cuiyan [Shandong University, Department of MR Imaging, Shandong Medical Imaging Research Institute, Jinan, Shandong (China); Liu, Hui [Siemens Healthcare, MR Collaborations NE Asia, Shanghai (China)

    2015-04-01

    To evaluate the influence of scan duration on pharmacokinetic parameters and their performance in differentiating benign from malignant breast lesions. Dynamic breast imaging was performed on a 3.0-T MR system using a prototype CAIPIRINHA-Dixon-TWISTVIBE (CDT-VIBE) sequence with a temporal resolution of 11.9 s. Enrolled in the study were 53 women with 55 lesions (26 benign and 29 malignant). Pharmacokinetic parameters (Ktrans, ve, kep and iAUC) were calculated for various scan durations from 1 to 7 min after injection of contrast medium using the Tofts model. Ktrans, kep and ve calculated from the 1-min dataset were significantly different from those calculated from the other datasets. In benign lesions, Ktrans, kep and ve were significantly different only between 1 min and 2 min (corrected P > 0.05), but in malignant lesions there were significant differences for any of the comparisons up to 6 min vs. 7 min (corrected P > 0.05). There were no significant differences in AUCs for any of the parameters (P > 0.05). In breast dynamic contrast-enhanced MRI the scan duration has a significant impact on pharmacokinetic parameters, but the diagnostic ability may not be significantly affected. A scan duration of 5 min after injection of contrast medium may be sufficient for calculation of Tofts model pharmacokinetic parameters. (orig.)

  10. Influence of scan duration on the estimation of pharmacokinetic parameters for breast lesions: a study based on CAIPIRINHA-Dixon-TWIST-VIBE technique

    International Nuclear Information System (INIS)

    Hao, Wen; Zhao, Bin; Wang, Guangbin; Wang, Cuiyan; Liu, Hui

    2015-01-01

    To evaluate the influence of scan duration on pharmacokinetic parameters and their performance in differentiating benign from malignant breast lesions. Dynamic breast imaging was performed on a 3.0-T MR system using a prototype CAIPIRINHA-Dixon-TWISTVIBE (CDT-VIBE) sequence with a temporal resolution of 11.9 s. Enrolled in the study were 53 women with 55 lesions (26 benign and 29 malignant). Pharmacokinetic parameters (Ktrans, ve, kep and iAUC) were calculated for various scan durations from 1 to 7 min after injection of contrast medium using the Tofts model. Ktrans, kep and ve calculated from the 1-min dataset were significantly different from those calculated from the other datasets. In benign lesions, Ktrans, kep and ve were significantly different only between 1 min and 2 min (corrected P > 0.05), but in malignant lesions there were significant differences for any of the comparisons up to 6 min vs. 7 min (corrected P > 0.05). There were no significant differences in AUCs for any of the parameters (P > 0.05). In breast dynamic contrast-enhanced MRI the scan duration has a significant impact on pharmacokinetic parameters, but the diagnostic ability may not be significantly affected. A scan duration of 5 min after injection of contrast medium may be sufficient for calculation of Tofts model pharmacokinetic parameters. (orig.)

  11. Efavirenz, tenofovir and emtricitabine combined with first-line tuberculosis treatment in tuberculosis-HIV-coinfected Tanzanian patients: a pharmacokinetic and safety study.

    Science.gov (United States)

    Semvua, Hadija H; Mtabho, Charles M; Fillekes, Quirine; van den Boogaard, Jossy; Kisonga, Riziki M; Mleoh, Liberate; Ndaro, Arnold; Kisanga, Elton R; van der Ven, Andre; Aarnoutse, Rob E; Kibiki, Gibson S; Boeree, Martin J; Burger, David M

    2013-01-01

    To evaluate the effect of rifampicin-based tuberculosis (TB) treatment on the pharmacokinetics of efavirenz/tenofovir/emtricitabine in a fixed-dose combination tablet, and vice versa, in Tanzanian TB-HIV-coinfected patients. This was a Phase II open-label multiple dose pharmacokinetic and safety study. This study was conducted in TB-HIV-coinfected Tanzanian patients who started TB treatment (rifampicin/isoniazid/pyrazinamide/ethambutol) at week 1 to week 8 and continued with rifampicin and isoniazid for another 16 weeks. Antiretroviral treatment (ART) of efavirenz/tenofovir/emtricitabine in a fixed-dose combination tablet was started at week 4 after initiation of TB treatment. A 24-h pharmacokinetic sampling curve was recorded at week 8 (with TB treatment) and week 28 (ART alone). For TB drugs, blood samples at 2 and 5 h post-dose were taken at week 3 (TB treatment alone) and week 8 (with ART). A total of 25 patients (56% male) completed the study; 21 had evaluable pharmacokinetic profiles. The area under the concentration-time curve 0-24 h post-dose of efavirenz, tenofovir and emtricitabine were slightly higher when these drugs were coadministered with TB drugs; geometric mean ratios (90% CI) were 1.08 (0.90, 1.30), 1.13 (0.93, 1.38) and 1.05 (0.85, 1.29), respectively. For TB drugs, equivalence was suggested for peak plasma concentrations when administered with and without efavirenz/tenofovir/emtricitabine. Adverse events were mostly mild and no serious adverse events or drug discontinuations were reported. Coadministration of efavirenz, tenofovir and emtricitabine with a standard first-line TB treatment regimen did not significantly alter the pharmacokinetic parameters of these drugs and was tolerated well by Tanzanian TB patients who are coinfected with HIV.

  12. Fiber optic-based fluorescence detection system for in vivo studies of exogenous chromophore pharmacokinetics

    Science.gov (United States)

    Doiron, Daniel R.; Dunn, J. B.; Mitchell, W. L.; Dalton, Brian K.; Garbo, Greta M.; Warner, Jon A.

    1995-05-01

    The detection and quantification of the concentration of exogenous chromophores in-vivo by their fluorescence is complicated by many physical and geometrical parameters. Measurement of such signals is advantageous in determining the pharmacokinetics of photosensitizers such as those used in photodynamic therapy (PDT) or to assist in the diagnosis of tissue histological state. To overcome these difficulties a ratio based fiber optic contact fluorometer has been developed. This fluorescence detection system (FDS) uses the ratio of the fluorescence emission peak of the exogenous chromophore to that of endogenous chromophores, i.e. autofluorescence, to correct for a variety of parameters affecting the magnitude of the measured signals. By doing so it also minimizes the range of baseline measurements prior to exogenous drug injection, for various tissue types. Design of the FDS and results of its testing in animals and patients using the second generation photosensitizer Tin ethyletiopurpurin (SnET2) are presented. These results support the feasibility and usefulness of the Ratio FDS system.

  13. The Role of Anti-Drug Antibodies in the Pharmacokinetics, Disposition, Target Engagement, and Efficacy of a GITR Agonist Monoclonal Antibody in Mice.

    Science.gov (United States)

    Brunn, Nicholas D; Mauze, Smita; Gu, Danling; Wiswell, Derek; Ueda, Roanna; Hodges, Douglas; Beebe, Amy M; Zhang, Shuli; Escandón, Enrique

    2016-03-01

    Administration of biologics to enhance T-cell function is part of a rapidly growing field of cancer immunotherapy demonstrated by the unprecedented clinical success of several immunoregulatory receptor targeting antibodies. While these biologic agents confer significant anti-tumor activity through targeted immune response modulation, they can also elicit broad immune responses potentially including the production of anti-drug antibodies (ADAs). DTA-1, an agonist monoclonal antibody against GITR, is a highly effective anti-tumor treatment in preclinical models. We demonstrate that repeated dosing with murinized DTA-1 (mDTA-1) generates ADAs with corresponding reductions in drug exposure and engagement of GITR on circulating CD3(+) CD4(+) T cells, due to rapid hepatic drug uptake and catabolism. Mice implanted with tumors after induction of preexisting mDTA-1 ADA show no anti-tumor efficacy when given 3 mg/kg mDTA-1, an efficacious dose in naive mice. Nonetheless, increasing mDTA-1 treatment to 30 mg/kg in ADA-positive mice restores mDTA-1 exposure and GITR engagement on circulating CD3(+) CD4(+) T cells, thereby partially restoring anti-tumor efficacy. Formation of anti-mDTA-1 antibodies and changes in drug exposure and disposition does not occur in GITR(-/-) mice, consistent with a role for GITR agonism in humoral immunity. Finally, the administration of muDX400, a murinized monoclonal antibody against the checkpoint inhibitor PD-1, dosed alone or combined with mDTA-1 did not result in reduced muDX400 exposure, nor did it change the nature of the anti-mDTA-1 response. This indicates that anti-GITR immunogenicity may not necessarily impact the pharmacology of coadministered monoclonal antibodies, supporting combination immunomodulatory strategies. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  14. Prediction of clearance, volume of distribution and half-life by allometric scaling and by use of plasma concentrations predicted from pharmacokinetic constants: a comparative study.

    Science.gov (United States)

    Mahmood, I

    1999-08-01

    Pharmacokinetic parameters (clearance, CL, volume of distribution in the central compartment, VdC, and elimination half-life, t1/2beta) predicted by an empirical allometric approach have been compared with parameters predicted from plasma concentrations calculated by use of the pharmacokinetic constants A, B, alpha and beta, where A and B are the intercepts on the Y axis of the plot of plasma concentration against time and alpha and beta are the rate constants, both pairs of constants being for the distribution and elimination phases, respectively. The pharmacokinetic parameters of cefpiramide, actisomide, troglitazone, procaterol, moxalactam and ciprofloxacin were scaled from animal data obtained from the literature. Three methods were used to generate plots for the prediction of clearance in man: dependence of clearance on body weight (simple allometric equation); dependence of the product of clearance and maximum life-span potential (MLP) on body weight; and dependence of the product of clearance and brain weight on body weight. Plasma concentrations of the drugs were predicted in man by use of A, B, alpha and beta obtained from animal data. The predicted plasma concentrations were then used to calculate CL, VdC and t1/2beta. The pharmacokinetic parameters predicted by use of both approaches were compared with measured values. The results indicate that simple allometry did not predict clearance satisfactorily for actisomide, troglitazone, procaterol and ciprofloxacin. Use of MLP or the product of clearance and brain weight improved the prediction of clearance for these four drugs. Except for troglitazone, VdC and t1/2beta predicted for man by use of the allometric approach were comparable with measured values for the drugs studied. CL, VdC and t1/2beta predicted by use of pharmacokinetic constants were comparable with values predicted by simple allometry. Thus, if simple allometry failed to predict clearance of a drug, so did the pharmacokinetic constant

  15. Inhalation developmental toxicology studies: Gallium arsenide in mice and rats

    Energy Technology Data Exchange (ETDEWEB)

    Mast, T.J.; Greenspan, B.J.; Dill, J.A.; Stoney, K.H.; Evanoff, J.J.; Rommereim, R.L.

    1990-12-01

    Gallium arsenide is a crystalline compound used extensively in the semiconductor industry. Workers preparing solar cells and gallium arsenide ingots and wafers are potentially at risk from the inhalation of gallium arsenide dust. The potential for gallium arsenide to cause developmental toxicity was assessed in Sprague- Dawley rats and CD-1 (Swiss) mice exposed to 0, 10, 37, or 75 mg/m{sup 3} gallium arsenide, 6 h/day, 7 days/week. Each of the four treatment groups consisted of 10 virgin females (for comparison), and {approx}30 positively mated rats or {approx}24 positively mated mice. Mice were exposed on 4--17 days of gestation (dg), and rats on 4--19 dg. The day of plug or sperm detection was designated as 0 dg. Body weights were obtained throughout the study period, and uterine and fetal body weights were obtained at sacrifice (rats, 20 dg; mice, 18 dg). Implants were enumerated and their status recorded. Live fetuses were sexed and examined for gross, visceral, skeletal, and soft-tissue craniofacial defects. Gallium and arsenic concentrations were determined in the maternal blood and uterine contents of the rats (3/group) at 7, 14, and 20 dg. 37 refs., 11 figs., 30 tabs.

  16. Early reversal of profound rocuronium-induced neuromuscular blockade by sugammadex in a randomized multicenter study - Efficacy, safety, and pharmacokinetics

    NARCIS (Netherlands)

    Sparr, Harald J.; Vermeyen, Karel M.; Beaufort, Anton M.; Rietbergen, Henk; Proost, Johannes H.; Saldien, Vera; Velik-Salchner, Corinna; Wierda, J. Mark K. H.

    Background: Sugammadex reverses the neuromuscular blocking effects of rocuronium by chemical encapsulation. The efficacy, safety, and pharmacokinetics of sugammadex for reversal of profound rocuronium-induced neuromuscular blockade were evaluated. Methods: Ninety-eight male adult patients were

  17. Reduced clearance of rocuronium and sugammadex in patients with severe to end-stage renal failure: a pharmacokinetic study.

    NARCIS (Netherlands)

    Staals, L.M.; Snoeck, M.M.J.; Driessen, J.J.; Hamersvelt, H.W. van; Flockton, E.A.; Heuvel, M.W. van den; Hunter, J.M.

    2010-01-01

    BACKGROUND: Sugammadex is a selective relaxant binding agent designed to encapsulate the neuromuscular blocking agent, rocuronium. The sugammadex-rocuronium complex is eliminated by the kidneys. This trial investigated the pharmacokinetics (PKs) of sugammadex and rocuronium in patients with renal

  18. PHARMACOKINETICS AND PHARMACOKINETIC DYNAMIC RELATIONSHIP OF ROCURONIUM BROMIDE IN HUMANS

    NARCIS (Netherlands)

    WIERDA, JMKH; PROOST, JH; SCHIERE, S; HOMMES, FDM

    The existing human pharmacokinetic studies have been reviewed and compared with data derived from animals. The earliest study confirms the similarity of rocuronium to vecuronium with respect to the variables derived from the plasma concentration decay curves and the proportion excreted renally.

  19. Design, synthesis, and evaluation of bioactive molecules; Quantification of tricyclic pyrones from pharmacokinetic studies; Nanodelivery of siRNA; and Synthesis of viral protease inhibitors

    Science.gov (United States)

    Weerasekara, Sahani Manjitha

    Four research projects were carried out and they are described in this dissertation. Glycogen synthase kinase-3 beta (GSK3?) plays a pivotal and central role in the pathogenesis of Alzheimer's disease (AD) and protein kinase C (PKC) controls the function of other proteins via phosphorylation and involves in tumor promotion. In pursuit of identifying novel GSK3beta and/or PKC inhibitors, substituted quinoline molecules were designed and synthesized based on the structure-activity-relationship studies. Synthesized molecules were evaluated for their neural protective activities and selected molecules were further tested for inhibitory activities on GSK3beta and PKC enzymes. Among these compounds, compound 2 was found to have better GSK3beta enzyme inhibitory and MC65 cell protection activities at low nanomolar concentrations and poor PKC inhibitory activity whereas compound 3 shows better PKC inhibitory activity. This demonstrates the potential for uses of quinoline scaffold in designing novel compounds for AD and cancer. Pharmacokinetics and distribution profiles of two anti-Alzheimer molecules, CP2 and TP70, discovered in our laboratory were assessed using HPLC/MS. Plasma samples of mice and rats fed with TP70 via different routes over various times were analyzed to quantify the amounts of TP70 in plasma of both species. Distribution profiles of TP70 in various tissues of mice were studied and results show that TP70 penetrated the blood brain barrier and accumulated in the brain tissue in significant amounts. Similarly, the amount of CP2 in plasma of mice was analyzed. The HPLC analysis revealed that both compounds have good PK profiles and bioavailability, which would make them suitable candidates for further in vivo efficacy studies. Nanodelivery of specific dsRNA for suppressing the western corn rootworm (WCR, Diabrotica virgifera virgifera) genes was studied using modified chitosan or modified polyvinylpyrrolidinone (PVP) as nanocarriers. Computational

  20. Sunitinib in urothelial cancer: clinical, pharmacokinetic, and immunohistochemical study of predictors of response.

    LENUS (Irish Health Repository)

    Gallagher, David J

    2012-02-01

    BACKGROUND: Sunitinib has activity in patients with metastatic urothelial cancer (UC), but most patients do not respond. OBJECTIVE: To identify predictors of response to sunitinib. DESIGN, SETTING, AND PARTICIPANTS: Seventy-seven patients with advanced UC received sunitinib on one of two schedules at a single institution. Blood pressure (BP), immunohistochemistry (IHC), and pharmacokinetic (PK) results were correlated with response to sunitinib. MEASUREMENTS: BP was assessed on day 1 and 28 of each cycle and on day 14 of cycle 1. IHC was performed on 55 samples from 38 cases using mammalian target of rapamycin and hypoxia-inducible factor (HIF) pathway marker antibodies. Blood samples for PK analysis were collected from 15 patients at three time points. Response was assessed using Response Evaluation Criteria in Solid Tumors criteria. RESULTS AND LIMITATIONS: Sunitinib-induced hypertension predicted improved response when hypertension was categorized as a discrete (p = 0.02) or continuous variable (p = 0.005 [systolic BP] and p = 0.007 [diastolic BP]). The odds ratio of response was 12.5 (95% confidence interval, 1.95-246.8) for grade 3\\/4 hypertension compared with grade 0. Response was associated with low HIF-1alpha expression in primary (p = 0.07) tissue. A nonstatistically significant trend was seen for an association between greater drug concentration and best response. A correlation between expression markers within the same pathways was identified, phosphorylated-4EBP1 and phosphorylated-S6 (p = 6.5 x 10(-9)), and vascular endothelial growth factor receptor 2 and HIF-1alpha (p = 0.008). Results are limited by small numbers. CONCLUSIONS: Clinical and molecular biomarkers of response to sunitinib may have clinical relevance and require prospective validation. There is an urgent need for predictive biomarkers to guide the management of UC.

  1. Absolute oral bioavailability and pharmacokinetics of canagliflozin: A microdose study in healthy participants.

    Science.gov (United States)

    Devineni, Damayanthi; Murphy, Joseph; Wang, Shean-Sheng; Stieltjes, Hans; Rothenberg, Paul; Scheers, Ellen; Mamidi, Rao N V S

    2015-07-01

    Absolute oral bioavailability of canagliflozin was assessed by simultaneous oral administration with intravenous [(14) C]-canagliflozin microdose infusion in nine healthy men. Pharmacokinetics of canagliflozin, [(14) C]-canagliflozin, and total radioactivity, and safety and tolerability were assessed at prespecified timepoints. On day 1, single-dose oral canagliflozin (300 mg) followed 105 minutes later by intravenous [(14) C]-canagliflozin (10 µg, 200 nCi) was administered. After oral administration, the mean (SD) Cmax of canagliflozin was 2504 (482) ng/mL at 1.5 hours, AUC∞ 17,375 (3555) ng.h/mL, and t1/2 11.6 (0.70) hours. After intravenous administration, the mean (SD) Cmax of unchanged [(14) C]-canagliflozin was 17,605 (6901) ng/mL, AUC∞ 27,100 (10,778) ng.h/mL, Vdss 83.5 (29.2) L, Vdz 119 (41.6) L, and CL 12.2 (3.79) L/h. Unchanged [(14) C]-canagliflozin and metabolites accounted for about 57% and 43% of the plasma total [(14) C] radioactivity AUC∞ , respectively. For total [(14) C] radioactivity, the mean (SD) Cmax was 15,981 (2721) ng-eq/mL, and AUC∞ 53,755 (15,587) ng-eq.h/mL. Renal (34.5% in urine) and biliary (34.1% in feces) excretions were the major elimination pathways for total [(14) C] radioactivity. The absolute oral bioavailability of canagliflozin was 65% (90% confidence interval: 55.41; 76.07). Overall, oral canagliflozin 300 mg coadministered with intravenous [(14) C]-canagliflozin (10 µg) was generally well-tolerated in healthy men, with no treatment-emergent adverse events. © 2014, The American College of Clinical Pharmacology.

  2. Pharmacokinetics of Snake Venom

    Directory of Open Access Journals (Sweden)

    Suchaya Sanhajariya

    2018-02-01

    Full Text Available Understanding snake venom pharmacokinetics is essential for developing risk assessment strategies and determining the optimal dose and timing of antivenom required to bind all venom in snakebite patients. This review aims to explore the current knowledge of snake venom pharmacokinetics in animals and humans. Literature searches were conducted using EMBASE (1974–present and Medline (1946–present. For animals, 12 out of 520 initially identified studies met the inclusion criteria. In general, the disposition of snake venom was described by a two-compartment model consisting of a rapid distribution phase and a slow elimination phase, with half-lives of 5 to 48 min and 0.8 to 28 h, respectively, following rapid intravenous injection of the venoms or toxins. When the venoms or toxins were administered intramuscularly or subcutaneously, an initial absorption phase and slow elimination phase were observed. The bioavailability of venoms or toxins ranged from 4 to 81.5% following intramuscular administration and 60% following subcutaneous administration. The volume of distribution and the clearance varied between snake species. For humans, 24 out of 666 initially identified publications contained sufficient information and timed venom concentrations in the absence of antivenom therapy for data extraction. The data were extracted and modelled in NONMEM. A one-compartment model provided the best fit, with an elimination half-life of 9.71 ± 1.29 h. It is intended that the quantitative information provided in this review will provide a useful basis for future studies that address the pharmacokinetics of snakebite in humans.

  3. A phase I pharmacokinetic study of ursolic acid nanoliposomes in healthy volunteers and patients with advanced solid tumors

    Directory of Open Access Journals (Sweden)

    Ying G

    2013-01-01

    Full Text Available Zhongling Zhu,1,4 Zhengzi Qian,2,4 Zhao Yan,1,4 Cuicui Zhao,2,4 Huaqing Wang,2,4 Guoguang Ying3,41Department of Clinical Pharmacology, 2Department of Lymphoma, 3Laboratory of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, People's Republic of China; 4Key Laboratory of Cancer Prevention and Therapy, Tianjin, People’s Republic of ChinaBackground: Ursolic acid is a promising anticancer agent. The current study aims to evaluate the single- and multiple-dose pharmacokinetics (PK as well as the safety of ursolic acid nanoliposomes (UANL in healthy volunteers and in patients with advanced solid tumors.Methods: Twenty-four healthy volunteers in the single-dose PK study were divided into three different groups, which received 37, 74, and 98 mg/m2 of UANL. Eight patients in the multiple-dose PK study were administered with 74 mg/m2 of UANL daily for 14 days. The UA plasma concentrations were determined using ultra-performance liquid chromatograph-tandem mass spectrometry.Results: The plasma concentration profiles of all subjects were characterized by a biexponential decline after infusion. The mean peak plasma concentration (Cmax increased linearly as a function of the dose (r = 0.999. The mean area under the plasma concentration-time curve (AUC from 0 to 16 hours also increased proportionally with dose escalation (r = 0.998. However, the clearance was constant over the specific dose interval. In the multiple-dose PK study, the trough and average concentrations remained low. The mean AUC, half-life, Cmax, time to Cmax, and the volume of distribution on the first day were similar to those on the last day. All subjects tolerated the treatments well. Most UANL-associated adverse events varied from mild to moderate.Conclusions: UANL exhibits relatively linear PK behavior with dose levels from 37 mg/m2 to 98 mg/m2. No drug accumulation was observed with repeated doses of UANL. The intravenous infusion of UANL was well

  4. Pharmacokinetics and toxicology of continuously infused nitroimidazoles

    International Nuclear Information System (INIS)

    Eifel, P.J.; Brown, J.M.

    1984-01-01

    The pharmacokinetics and toxicology of misonidazole (MISO) and SR-2508 given by continuous intraperitoneal infusion were studied in female C 3 H mice. The survival (time to death) of animals receiving continuous infusions of SR-2508 and MISO was compared and related to plasma concentration, rate of infusion and total amount of drug delivered. Brain and plasma concentrations were determined by HPLC. For SR-2508, plasma concentration was directly proportional to the infusion rate. However, as the infusion rate of MISO was doubled, the plasma concentration of MISO increased approximately 6-fold, reflecting a substantial increase in the apparent half-life. The brain/plasma concentration ratio in animals infused for up to 6 days with SR-2508 remained constant, at approximately 0.09. At plasma concentrations of 0.08-1.5 mM, animals receiving SR-2508 survived approximately 3 times as long as animals exposed to a comparable plasma concentration of MISO. Even at the lowest infusion rates employed in this study, the survival of mice receiving SR-2508 was much shorter than would have been predicted if the toxicity of these two drugs were solely related to the integral brain exposure. The low brain/plasma concentration ratio of SR-2508 was maintained throughout long continuous exposures

  5. The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections - a pharmacokinetic study

    Science.gov (United States)

    Hsu, Chao-Chin; Kuo, Hsin-Chih; Hsu, Chao-Tien; Gu, Qing

    2009-01-01

    Background Follicle stimulating hormone (FSH) has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF). To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally. Methods Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300) either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax) and time of maximal plasma concentrations (tmax)] and extent [area under the plasma concentration-time curve (AUC) and clearance] of absorption of rhFSH were compared. Results Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours) and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L) in vaginal versus abdominal injections. The AUC0-∞ was 1640 versus 1134 IU·hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1), longer mean residence time (106.58 versus 70.47 hours), and slower total body clearance (292.2 versus 400.1 mL/hour) were also found in vaginal injection. Conclusion The vaginal

  6. The absorption and uptake of recombinant human follicle-stimulating hormone through vaginal subcutaneous injections - a pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Kuo Hsin-Chih

    2009-10-01

    Full Text Available Abstract Background Follicle stimulating hormone (FSH has been routinely used for ovulation induction. Because of rapid clearance of the hormone, FSH is commonly administered by daily intramuscular or subcutaneous injections in in-vitro fertilization (IVF. To reduce the number of visits to the clinic, an intermittent vaginal injection of rhFSH every 3 days employing the concepts of mesotherapy and uterine first-pass effect was invented and has successfully been applied in women receiving IVF treatment. This study was designed to monitor the pharmacokinetic pattern of rhFSH administered vaginally. Methods Twelve healthy women with regular ovulatory cycles were recruited. All volunteers received gonadotrophin-releasing hormone agonist to suppress pituitary function and were assigned to receive single dose recombinant human FSH (rhFSH, Puregon 300 either using conventional abdominal subcutaneous injection or vaginal subcutaneous injection in a randomized cross-over study. Serum samples were collected at pre- scheduled time intervals after injections of rhFSH to determine immunoreactive FSH levels. Pharmacokinetic parameters characterizing rate [maximal plasma concentrations (Cmax and time of maximal plasma concentrations (tmax] and extent [area under the plasma concentration-time curve (AUC and clearance] of absorption of rhFSH were compared. Results Vaginal injection of rhFSH was well tolerated and no drug-related adverse reaction was noted. Our analysis revealed that tmax was significantly earlier (mean 6.67 versus 13.33 hours and Cmax was significantly higher (mean 17.77 versus 13.96 IU/L in vaginal versus abdominal injections. The AUC0-∞ was 1640 versus 1134 IU·hour/L in vaginal and abdominal injections, respectively. Smaller plasma elimination rate constant (0.011 versus 0.016 hour-1, longer mean residence time (106.58 versus 70.47 hours, and slower total body clearance (292.2 versus 400.1 mL/hour were also found in vaginal injection

  7. In vivo evaluation of different alterations of redox status by studying pharmacokinetics of nitroxides using magnetic resonance techniques

    Science.gov (United States)

    Bačić, Goran; Pavićević, Aleksandra; Peyrot, Fabienne

    2015-01-01

    Free radicals, particularly reactive oxygen species (ROS), are involved in various pathologies, injuries related to radiation, ischemia-reperfusion or ageing. Unfortunately, it is virtually impossible to directly detect free radicals in vivo, but the redox status of the whole organism or particular organ can be studied in vivo by using magnetic resonance techniques (EPR and MRI) and paramagnetic stable free radicals – nitroxides. Here we review results obtained in vivo following the pharmacokinetics of nitroxides on experimental animals (and a few in humans) under various conditions. The focus was on conditions where the redox status has been altered by induced diseases or harmful agents, clearly demonstrating that various EPR/MRI/nitroxide combinations can reliably detect metabolically induced changes in the redox status of organs. These findings can improve our understanding of oxidative stress and provide a basis for studying the effectiveness of interventions aimed to modulate oxidative stress. Also, we anticipate that the in vivo EPR/MRI approach in studying the redox status can play a vital role in the clinical management of various pathologies in the years to come providing the development of adequate equipment and probes. PMID:26827126

  8. In vivo evaluation of different alterations of redox status by studying pharmacokinetics of nitroxides using magnetic resonance techniques

    Directory of Open Access Journals (Sweden)

    Goran Bačić

    2016-08-01

    Full Text Available Free radicals, particularly reactive oxygen species (ROS, are involved in various pathologies, injuries related to radiation, ischemia-reperfusion or ageing. Unfortunately, it is virtually impossible to directly detect free radicals in vivo, but the redox status of the whole organism or particular organ can be studied in vivo by using magnetic resonance techniques (EPR and MRI and paramagnetic stable free radicals – nitroxides. Here we review results obtained in vivo following the pharmacokinetics of nitroxides on experimental animals (and a few in humans under various conditions. The focus was on conditions where the redox status has been altered by induced diseases or harmful agents, clearly demonstrating that various EPR/MRI/nitroxide combinations can reliably detect metabolically induced changes in the redox status of organs. These findings can improve our understanding of oxidative stress and provide a basis for studying the effectiveness of interventions aimed to modulate oxidative stress. Also, we anticipate that the in vivo EPR/MRI approach in studying the redox status can play a vital role in the clinical management of various pathologies in the years to come providing the development of adequate equipment and probes.

  9. Linking Suspension Nasal Spray Drug Deposition Patterns to Pharmacokinetic Profiles: A Proof of Concept Study using Computational Fluid Dynamics

    Science.gov (United States)

    Rygg, Alex; Hindle, Michael; Longest, P. Worth

    2016-01-01

    The objective of this study is to link regional nasal spray deposition patterns of suspension formulations, predicted with computational fluid dynamics (CFD), to in vivo human pharmacokinetic (PK) plasma concentration profiles. This is accomplished through the use of CFD simulations coupled with compartmental PK modeling. Results showed a rapid initial rise in plasma concentration that is due to the absorption of drug particles deposited in the nasal middle passages, followed by a slower increase in plasma concentration that is governed by the transport of drug particles from the nasal vestibule to the middle passages. Although drug deposition locations in the nasal cavity had a significant effect on the shape of the concentration profile, the absolute bioavailability remained constant provided that all of the drug remained in the nose over the course of the simulation. Loss of drug through the nostrils even after long time periods resulted in a significant decrease in bioavailability and increased variability. The results of this study quantify how differences in nasal drug deposition affect transient plasma concentrations and overall bioavailability. These findings are potentially useful for establishing bioequivalence for nasal spray devices and reducing the burden of in vitro testing, pharmacodynamics and clinical studies. PMID:27238495

  10. Pharmacokinetics and radiation dosimetry of 99mTc-3PRGD2 in healthy individuals: A pilot study

    International Nuclear Information System (INIS)

    Cheng Guanghui; Gao Shi; JI Tiefeng; Ma Qingjie; Wang Qing; Jia Bing; Chen Zuowei

    2012-01-01

    99m Tc-3PRGD 2 is a new SPECT radiotracer for several tumor imaging with high uptake where integrin α v β 3 is highly expressed. This pilot study was to assess the safety, biodistribution and radiation dosimetry of 99m Tc-3PRGD 2 in healthy volunteers. The 10 healthy male volunteers were injected with 99m Tc-3PRGD 2 (786.7±55.8 MBq, 19.1-24.2 mCi). Baseline measurements of vital signs, laboratory safety tests and 12-lead electrocardiogram were recorded before and after injection. Blood and urine samples were collected and radiation counts were obtained at various time points. Whole-body scans and ROIs of identified organs were used for visual analysis and estimating the radiation dosimetry. No adverse reactions were found during the study. 99m Tc-3PRGD 2 exhibited a rapid clearance from the blood with less than 45% of the initial dosage at 10 min after injection and gradual increasing radioactivity in urine with (52.9±6)% of original dose at 1440 min. The whole-body imaging showed high radioactive accumulation in bladder. And the highest 99m Tc-3PRGD 2 uptake was found in the kidneys (3.50×10 -2 mSv/MBq). The 99m Tc-3PRGD 2 exhibited good pharmacokinetic properties and little radiation burden. This study showed that 99m Tc-3PRGD 2 would be a safe and attractive SPECT agent in clinic applications. (authors)

  11. A Study on Pharmacokinetics of Bosentan with Systems Modeling, Part 2: Prospectively Predicting Systemic and Liver Exposure in Healthy Subjects.

    Science.gov (United States)

    Li, Rui; Kimoto, Emi; Niosi, Mark; Tess, David A; Lin, Jian; Tremaine, Larry M; Di, Li

    2018-04-01

    Predicting human pharmacokinetics of novel compounds is a critical step in drug discovery and clinical study design but continues to be a challenging task for hepatic transporter substrates, particularly in predicting their liver exposures. In this study, using bosentan as an example, we prospectively predicted systemic exposure and the (pseudo) steady-state unbound liver-to-unbound plasma ratio ( K p uu ) in healthy subjects using 1) a mechanistic approach solely based on in vitro hepatocyte assays and 2) an approach based on hepatic process rates from monkey in vivo data but Michaelis-Menten constants from in vitro data. Both methods reasonably match the observed human systemic time course data, but the second method leads to better prediction accuracy. In addition, the second method can predict a human K p uu value that is close to the value deduced using clinical data. We also generated rat and monkey liver K p uu values in terminal studies. However, these directly measured animal values are different from the deduced human value. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

  12. Computational Analysis of Pharmacokinetic Behavior of Ampicillin

    Directory of Open Access Journals (Sweden)

    Mária Ďurišová

    2016-07-01

    Full Text Available orrespondence: Institute of Experimental Pharmacology and Toxicology, Slovak Academy of Sciences, 841 04 Bratislava, Slovak Republic. Phone + 42-1254775928; Fax +421254775928; E-mail: maria.durisova@savba.sk 84 RESEARCH ARTICLE The objective of this study was to perform a computational analysis of the pharmacokinetic behavior of ampicillin, using data from the literature. A method based on the theory of dynamic systems was used for modeling purposes. The method used has been introduced to pharmacokinetics with the aim to contribute to the knowledge base in pharmacokinetics by including the modeling method which enables researchers to develop mathematical models of various pharmacokinetic processes in an identical way, using identical model structures. A few examples of a successful use of the modeling method considered here in pharmacokinetics can be found in full texts articles available free of charge at the website of the author, and in the example given in the this study. The modeling method employed in this study can be used to develop a mathematical model of the pharmacokinetic behavior of any drug, under the condition that the pharmacokinetic behavior of the drug under study can be at least partially approximated using linear models.

  13. Imaging Primary Lung Cancers in Mice to Study Radiation Biology

    International Nuclear Information System (INIS)

    Kirsch, David G.; Grimm, Jan; Guimaraes, Alexander R.; Wojtkiewicz, Gregory R.; Perez, Bradford A.; Santiago, Philip M.; Anthony, Nikolas K.; Forbes, Thomas; Doppke, Karen

    2010-01-01

    Purpose: To image a genetically engineered mouse model of non-small-cell lung cancer with micro-computed tomography (micro-CT) to measure tumor response to radiation therapy. Methods and Materials: The Cre-loxP system was used to generate primary lung cancers in mice with mutation in K-ras alone or in combination with p53 mutation. Mice were serially imaged by micro-CT, and tumor volumes were determined. A comparison of tumor volume by micro-CT and tumor histology was performed. Tumor response to radiation therapy (15.5 Gy) was assessed with micro-CT. Results: The tumor volume measured with free-breathing micro-CT scans was greater than the volume calculated by histology. Nevertheless, this imaging approach demonstrated that lung cancers with mutant p53 grew more rapidly than lung tumors with wild-type p53 and also showed that radiation therapy increased the doubling time of p53 mutant lung cancers fivefold. Conclusions: Micro-CT is an effective tool to noninvasively measure the growth of primary lung cancers in genetically engineered mice and assess tumor response to radiation therapy. This imaging approach will be useful to study the radiation biology of lung cancer.

  14. Battery of behavioral tests in mice to study postoperative delirium

    Science.gov (United States)

    Peng, Mian; Zhang, Ce; Dong, Yuanlin; Zhang, Yiying; Nakazawa, Harumasa; Kaneki, Masao; Zheng, Hui; Shen, Yuan; Marcantonio, Edward R.; Xie, Zhongcong

    2016-01-01

    Postoperative delirium is associated with increased morbidity, mortality and cost. However, its neuropathogenesis remains largely unknown, partially owing to lack of animal model(s). We therefore set out to employ a battery of behavior tests, including natural and learned behavior, in mice to determine the effects of laparotomy under isoflurane anesthesia (Anesthesia/Surgery) on these behaviors. The mice were tested at 24 hours before and at 6, 9 and 24 hours after the Anesthesia/Surgery. Composite Z scores were calculated. Cyclosporine A, an inhibitor of mitochondria permeability transient pore, was used to determine potential mitochondria-associated mechanisms of these behavioral changes. Anesthesia/Surgery selectively impaired behaviors, including latency to eat food in buried food test, freezing time and time spent in the center in open field test, and entries and duration in the novel arm of Y maze test, with acute onset and various timecourse. The composite Z scores quantitatively demonstrated the Anesthesia/Surgery-induced behavior impairment in mice. Cyclosporine A selectively ameliorated the Anesthesia/Surgery-induced reduction in ATP levels, the increases in latency to eat food, and the decreases in entries in the novel arm. These findings suggest that we could use a battery of behavior tests to establish a mouse model to study postoperative delirium. PMID:27435513

  15. Instruments for radiation measurement in life sciences (4). VI. Use of Accelerator mass spectrometry in studies on drug metabolism and pharmacokinetics

    International Nuclear Information System (INIS)

    Ikeda, Toshihiko

    2005-01-01

    Non-clinical and clinical uses of accelerator mass spectrometry (AMS) are described mainly on studies of drug metabolism and pharmacokinetics from a view of new drug development. AMS is applicable as a highly sensitive method to measure plasma drug concentrations. Measurement of 14 C-labeled compounds less than 1 dpm/sample or of parathyroid hormone-related protein (PTHrP), in combination of AMS and radioimmunoassay without radioactive waste release is described as an example. Cases of measuring DNA-adduct are also described involving human studies using 14 C-mutagen (a quinoxaline derivative derived from burned amino acid, given in a microdose of 304 ng/kg, 4.3 μCi/body). Plasma concentration measurement, mass balance study and metabolite identification of 14 C-GI1817771 (a drug candidate) are a typical AMS application for a pharmacokinetic study in human in a microdose (121 Bq/body). Metabolites of 14 C-compound A in rat platelet are identified by the author. As above, AMS makes it possible to conduct the pharmacokinetic study in human at a microdose with no significant radiation exposure, which will promote the efficient new drug development. (N.I.)

  16. LC determination and pharmacokinetic study of the main phenolic components of Portulaca oleracea L. extract in rat plasma after oral administration.

    Science.gov (United States)

    Cheng, Zhongzhe; Wang, Dong; Zhang, Wenjie; Du, Yang; Wang, Yunjiao; Zhai, Yanjun; Ying, Xixiang; Kang, Tingguo

    2012-01-01

    This study investigated the pharmacokinetics of hesperidin (HP), ferulic acid (FA) and p-coumaric acid (CA) in rat plasma after oral administration of Portulaca oleracea L. extract (POE). The plasma concentrations were determined by HPLC with vitexin-2″-O-rhamnoside (VR) as internal standard. The calibration curves were linear over the range 0.1-5 µg mL(-1), 0.1-5 µg mL(-1)and 0.015-3 µg mL(-1) for HP, FA and CA, respectively. The validated method was suitable to the pharmacokinetic study of HP, FA and CA in rats after oral administration at a single dose of POE.

  17. Pharmacokinetics and Dosimetry Studies for Optimization of Pretargeted Radioimmunotherapy in CEA-Expressing Advanced Lung Cancer Patients

    Directory of Open Access Journals (Sweden)

    Caroline eBodet-Milin

    2015-11-01

    Full Text Available Objectives. A phase I pretargeted radioimmunotherapy trial (EudractCT 200800603096 was designed in patients with metastatic lung cancer expressing carcinoembryonic antigen (CEA to optimize bispecific antibody and labelled peptide doses, as well as the delay between their injections.Methods. Three cohorts of 3 patients received the anti-CEA x anti-histamine-succinyl-glycine (HSG humanized trivalent bispecific antibody (TF2 and the IMP288 bivalent HSG-peptide. Patients underwent a pre-therapeutic imaging session S1 (44 or 88 nmol/m2 of TF2 followed by 4.4 nmol/m2, 185 MBq, of 111In-labelled IMP288, and, 1-2 weeks later, a therapy session S2 (240 or 480 nmol/m2 of TF2 followed by 24 nmol/m2, 1.1 GBq/m2, 177Lu-labeled IMP288. The pretargeting delay was 24 or 48 hours. The dose schedule was defined based on pre-clinical TF2 pharmacokinetic studies, on our previous clinical data using the previous anti-CEA pretargeting system and on clinical results observed in the first patients injected using the same system in the Netherlands.Results. TF2 pharmacokinetics (PK was represented by a two-compartment model in which the central compartment volume was linearly dependent on the patient's surface area. PK were remarkably similar, with a clearance of 0.33 +/- 0.03 L/h per m2. 111In- and 177Lu-IMP288 PK were also well represented by a two-compartment model. IMP288 PK were faster (clearance 1.4 to 3.3 l/h. The central compartment volume was proportional to body surface area and IMP288clearance depended on the molar ratio of injected IMP288 to circulating TF2 at the time of IMP288 injection. Modelling of image quantification confirmed the dependence of IMP288 kinetics on circulating TF2, but tumour activity PK were variable. Organ absorbed doses were not significantly different in the 3 cohorts, but the tumour dose was significantly higher with the higher molar doses of TF2 (p < 0.002. S1 imaging predicted absorbed doses calculated in S2. Conclusion. The best

  18. Quantitation of clevidipine in dog blood by liquid chromatography tandem mass spectrometry: application to a pharmacokinetic study.

    Science.gov (United States)

    Wei, Huihui; Gu, Yuan; Liu, Yanping; Chen, Yong; Liu, Changxiao; Si, Duanyun

    2014-11-15

    Clevidipine, a vascular selective calcium channel antagonist of the dihydropyridine class, is rapidly metabolized by ester hydrolysis because of incorporation of an ester linkage into the drug molecule. To characterize its pharmacokinetic profiles in dogs, a simple, rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantitation of clevidipine in dog blood. After one-step protein precipitation with methanol, the chromatographic separation was carried out on an Ecosil C18 column (150mm×4.6mm, 5μm) with a gradient mobile phase consisting of methanol and 5mM ammonium formate at a flow rate of 0.5mL/min. The quantitation analysis was performed using multiple reaction monitoring (MRM) at the specific ion transitions of m/z 454.1 [M-H](-)→m/z 234.1 for clevidipine and m/z 256.1 [M-H](-)→m/z 227.1 for elofesalamide (internal standard) in the negative ion mode with electrospray ionization (ESI) source. This validated LC-MS/MS method showed good linearity over the range 0.5-100ng/mL with the lower limit of quantitation (LLOQ) of 0.5ng/mL together with the satisfied intra- and inter-day precision, accuracy, extraction recovery and matrix effect. Stability testing indicated that clevidipine in dog blood with the addition of denaturant methanol was stable on workbench for 1h, at -80°C for up to 30 days, and after three freeze-thaw cycles. Extracted samples were also observed to be stable over 24h in an auto-sampler at 4°C. The validated method has been successfully applied to a pharmacokinetic study of clevidipine injection to 8 healthy Beagle dogs following intravenous infusion at a flow rate of 5mg/h for 0.5h. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Liquid chromatography tandem mass spectrometry method for the estimation of lamotrigine in human plasma: Application to a pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Santosh Ghatol

    2013-04-01

    Full Text Available A reliable, selective and sensitive liquid chromatography tandem mass spectrometry method was developed and validated for the quantification of lamotrigine in human plasma using lamotrigine-13C3, d3 as an internal standard. Analyte and internal standard were extracted from human plasma by solid-phase extraction and detected in positive ion mode by tandem mass spectrometry with electrospray ionization (ESI interface. Chromatographic separation was performed on a Chromolith® SpeedROD; RP-18e column (50−4.6 mm i.d. using acetonitrile: 5±0.1 mM ammonium formate solution (90:10, v/v as the mobile phase at a flow rate of 0.500 mL/min. The calibration curves were linear over the range of 5.02–1226.47 ng/mL with the lower limit of quantitation validated at 5.02 ng/mL. The analytes were found stable in human plasma through three freeze (−20 °C-thaw (ice-cold water bath cycles and under storage on bench-top in ice-cold water bath for at least 6.8 h, and also in the mobile phase at 10 °C for at least 57 h. The method has shown good reproducibility, as the intra- and inter-day precisions were within 3.0%, while the accuracies were within ±6.0% of nominal values. The validated LC–MS/MS method was applied for the evaluation of pharmacokinetic and bioequivalence parameters of lamotrigine after an oral administration of 50 mg lamotrigine tablet to thirty-two healthy adult male volunteers. Keywords: Lamotrigine, Liquid chromatography/tandem mass spectrometry, Solid phase extraction, Pharmacokinetic study

  20. In vivo toxicologic study of larger silica nanoparticles in mice

    Directory of Open Access Journals (Sweden)

    Chan WT

    2017-04-01

    Full Text Available Wai-Tao Chan,1–3 Cheng-Che Liu,4 Jen-Shiu Chiang Chiau,5 Shang-Ting Tsai,6 Chih-Kai Liang,6 Mei-Lien Cheng,5 Hung-Chang Lee,7,8 Chun-Yun Yeung,1,3,9 Shao-Yi Hou2,6 1Department of Pediatric Gastroenterology, Hepatology and Nutrition, MacKay Children’s Hospital, 2Graduate Institute of Engineering Technology, National Taipei University of Technology, 3Mackay Medicine, Nursing, and Management College, 4Institute of Preventive Medicine, National Defense Medical Center, Taipei, 5Department of Medical Research, MacKay Memorial Hospital, Hsinchu, 6Graduate Institute of Biochemical and Biomedical Engineering, National Taipei University of Technology, Taipei, 7Department of Pediatrics, MacKay Memorial Hospital, Hsinchu, 8Department of Pediatrics, Taipei Medical University, Taipei, 9Department of Medicine, Mackay Medical College, New Taipei, Taiwan, Republic of China Abstract: Silica nanoparticles (SiNPs are being studied and used for medical purposes. As nanotechnology grows rapidly, its biosafety and toxicity have frequently raised concerns. However, diverse results have been reported about the safety of SiNPs; several studies reported that smaller particles might exhibit toxic effects to some cell lines, and larger particles of 100 nm were reported to be genotoxic to the cocultured cells. Here, we investigated the in vivo toxicity of SiNPs of 150 nm in various dosages via intravenous administration in mice. The mice were observed for 14 days before blood examination and histopathological assay. All the mice survived and behaved normally after the administration of nanoparticles. No significant weight change was noted. Blood examinations showed no definite systemic dysfunction of organ systems. Histopathological studies of vital organs confirmed no SiNP-related adverse effects. We concluded that 150 nm SiNPs were biocompatible and safe for in vivo use in mice. Keywords: in vivo, mice, silica nanoparticle, nanotoxicity

  1. In-vivo studies by positron emission tomography of the pharmacokinetics of L-6-F-18-fluorodopa

    International Nuclear Information System (INIS)

    Pate, B.D.; Calne, D.B.; Hewitt, K.A.; Ruth, T.J.; Adam, M.J.

    1989-01-01

    Positron emission tomography has been used to study the pharmacokinetics of fluorine-18-labelled L-6-fluorodopa in the brains of cynomolgus monkey subjects. The protocol for each experiment consisted of two series of twelve 10-minutes scans, conducted one after the other with the monkey in the same position, with an inhibitor acting at a specific stage of the kinetics, administered before the second series. Subtractions of the two scan series (following correction for activity residue in the second scans) then gave a quantitative measure of the effects produced by the inhibitor. The inhibitors studied include NSD 1015 (decarboxylase inhibitor), chlorgyline (MAO-A inhibitor), deprenyl (MAO-B inhibitor), pargyline (inhibitor of both MAO-A and MAO-B), U-0521 (COMT inhibitor), and reserpine (vesicular storage inhibitor). The results show that L-6-fluorodopa is a substrate for dopa decarboxylase, while fluorodopamine is a substrate for both MAO-A and MAO-B, and for COMT. Vesicular storage (inhibited by reserpine) was shown also to be essential for concentration of the activity into striatal images

  2. Phase I study of TP300 in patients with advanced solid tumors with pharmacokinetic, pharmacogenetic and pharmacodynamic analyses

    International Nuclear Information System (INIS)

    Anthoney, D Alan; Miwa, Masanori; Twelves, Christopher; Evans, TRJ; Naik, Jay; MacPherson, Iain RJ; Crawford, Donna; Hartley, John M; Hartley, Janet A; Saito, Tomohisa; Abe, Masaichi; Jones, Keith

    2012-01-01

    A Phase I dose escalation first in man study assessed maximum tolerated dose (MTD), dose-limiting toxicity (DLT) and recommended Phase II dose of TP300, a water soluble prodrug of the Topo-1 inhibitor TP3076, and active metabolite, TP3011. Eligible patients with refractory advanced solid tumors, adequate performance status, haematologic, renal, and hepatic function. TP300 was given as a 1-hour i.v. infusion 3-weekly and pharmacokinetic (PK) profiles of TP300, TP3076 and TP3011 were analysed. Polymorphisms in CYP2D6, AOX1 and UGT1A1 were studied and DNA strand-breaks measured in peripheral blood mononuclear cells (PBMCs). 32 patients received TP300 at 1, 2, 4, 6, 8, 10, 12 mg/m 2 . MTD was 10 mg/m 2 ; DLTs at 12 (2/4 patients) and 10 mg/m 2 (3/12) included thrombocytopenia and febrile neutropenia; diarrhoea was uncommon. Six patients (five had received irinotecan), had stable disease for 1.5-5 months. TP3076 showed dose proportionality in AUC and C max from 1–10 mg/m 2 . Genetic polymorphisms had no apparent influence on exposure. DNA strand-breaks were detected after TP300 infusion. TP300 had predictable hematologic toxicity, and diarrhoea was uncommon. AUC at MTD is substantially greater than for SN38. TP3076 and TP3011 are equi-potent with SN38, suggesting a PK advantage. EU-CTR2006-001345-33

  3. Simultaneous quantification of preactivated ifosfamide derivatives and of 4-hydroxyifosfamide by high performance liquid chromatography-tandem mass spectrometry in mouse plasma and its application to a pharmacokinetic study.

    Science.gov (United States)

    Deroussent, Alain; Skarbek, Charles; Maury, Adeline; Chapuis, Hubert; Daudigeos-Dubus, Estelle; Le Dret, Ludivine; Durand, Sylvère; Couvreur, Patrick; Desmaële, Didier; Paci, Angelo

    2015-06-15

    The antitumor drug, ifosfamide (IFO), requires activation by cytochrome P450 (CYP) to form the active metabolite, 4-hydroxyisfosfamide (4-OHIFO), leading to toxic by-products at high dose. In order to overcome these drawbacks, preactivated ifosfamide derivatives (RXIFO) were designed to release 4-OHIFO without CYP involvement. A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the simultaneous quantification of 4-OHIFO, IFO and four derivatives RXIFO in mouse plasma using multiple reaction monitoring. Because of its instability in plasma, 4-OHIFO was immediately converted to the semi-carbazone derivative, 4-OHIFO-SCZ. For the six analytes, the calibration curves were linear from 20 to 5000ng/mL in 50μL plasma and the lower limit of quantitation was determined at 20ng/mL with accuracies within ±10% of nominal and precisions less than 12%. Their recoveries ranged from 62 to 96% by using liquid-liquid extraction. With an improved assay sensitivity compared to analogues, the derivative 4-OHIFO-SCZ was stable in plasma at 4°C for 24h and at -20°C for three months. For all compounds, the assay was validated with accuracies within ±13% and precisions less than 15%. This method was applied to a comparative pharmacokinetic study of 4-OHIFO from IFO and three derivatives RXIFO in mice. This active metabolite was produced by some of the novel conjugates with good pharmacokinetic properties. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Tumour localization and pharmacokinetics of iodine-125 human monoclonal IgM antibody (COU-1) and its monomeric and half-monomeric fragments analysed in nude mice grafted with human tumour

    International Nuclear Information System (INIS)

    Ditzel, H.; Erb, K.; Rasmussen, J.W.; Jensenius, J.C.

    1992-01-01

    Human monoclonal IgM antibodies reactive with cancer-associated antigens may not have the optimal imaging capability due to their large size. Fragmentation of human IgM is less than straight-forward due to the loss of immunoreactivity. From the human monoclonal IgM antibody COU-1 we have prepared monomeric and half-monomeric fragments, which retain the ability to bind to colon cancer cells in vitro. The pharmacokinetics and tumour localization were evaluated in nude mice bearing human colon adenocarcinoma and human melanoma grafts. Faster clearance from the circulation was seen for the smaller half-monomeric fragment with a half-life (rapid phase/slow phase) of 2 h/16 h compared with the intact antibody, 4 h/25 h, and the monomeric fragment, 3 h/27 h. Intact COU-1 as well as the fragments accumulated in the colon tumour graft. Higher amounts of radioactivity were found in the colon tumour as compared to normal organs for intact COU-1 at days 4 and 6, for the monomeric fragment at day 4, and for the half-monomeric fragment at day 2 after injection. This investigation demonstrates the favourable biodistribution of the half monomeric COU-1 fragment. The fast clearance of this fragment resulted in a tumour-to-muscle ratio as high as 22 on day 2 after injection. Also, only this fragment gave a positive tumour-to-blood ratio. Normal IgM and its fragments were used as controls. Radioimmunoscintigraphy demonstrated the colon tumour discriminatory properties of each of the three iodine-labelled antibody preparations. The results compare favourably with previously reported investigations of the localization of human monoclonal antibodies and suggest that fragments of human monoclonal IgM antibodies may be useful tools for the immunodetection of cancer in patients. (orig.)

  5. Simultaneous Determination of Multiple Components in Guanjiekang in Rat Plasma via the UPLC–MS/MS Method and Its Application in Pharmacokinetic Study

    Directory of Open Access Journals (Sweden)

    Jian Wu

    2016-12-01

    Full Text Available Guanjiekang (GJK that is formed by five medicinal herbs including Astragali Radix, Aconiti Lateralis Radix Praeparaia, Glycyrrhizae Radix et Rhizoma, Corydalis Rhizoma and Paeoniae Radix Alba was used for the treatment of rheumatoid arthritis (RA. However, the pharmacokinetic (PK profile of active components in GJK remains unclear. This study aims to evaluate the pharmacokinetic behavior of seven representative active constituents in GJK (i.e., benzoylhypaconine, benzoylmesaconine, paeoniflorin, tetrahydropalmatine, calycosin-7-glucoside, formononetin and isoliquiritigenin after oral administration of GJK in rats. A rapid, sensitive and reliable ultra-performance liquid chromatography-tandem mass spectrometer (UPLC–MS/MS method has been successfully developed for the simultaneous determination of these seven constituents in rat plasma. Chromatographic separation was achieved on a C18 column with a gradient elution program that consists of acetonitrile and water (containing 0.1% formic acid at a flow rate of 0.35 mL/min. Detection was performed under the multiple reaction monitoring (MRM in the positive electrospray ionization (ESI mode. The calibration curves exhibited good linearity (R2 > 0.99 over a wide concentration range for all constituents. The accuracies ranged from 92.9% to 107.8%, and the intra-day and inter-day precisions at three different levels were below 15%. Our PK results showed that these seven compounds were quickly absorbed after the administration of the GJK product, and Tmax ranged from 30 min to 189 min. The in vivo concentrations of paeoniflorin and isoliquiritigenin were significantly higher than the reported in vitro effective doses, indicating that they could partly contribute to the therapeutic effect of GJK. Therefore, we conclude that pharmacokinetic studies of representative bioactive chemicals after administration of complex herbal products are not only necessary but also feasible. Moreover, these seven

  6. Determination of 6258-70, a new semi-synthetic taxane, in rat plasma and tissues: Application to the pharmacokinetics and tissue distribution study

    Directory of Open Access Journals (Sweden)

    Simin Zhao

    2016-08-01

    Full Text Available Cancer is the leading cause of death all over the world. Among the chemotherapy drugs, taxanes play an important role in cancer treatment. 6258-70 is a new semi-synthetic taxane which has a broad spectrum of antitumor activity. A fast and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC–MS/MS method was developed for quantification of 6258-70 in rat plasma and tissues in this paper. After extraction by liquid-liquid extraction method with methyl tert-butyl ether, the samples were separated on a Kinetex C18 column (50 mm×2.1 mm, 2.6 µm, Phenomenex, USA within 3 min. The method was fully validated with the matrix effect between 87.7% and 99.5% and the recovery ranging from 80.3% to 90.1%. The intra- and inter-day precisions were less than 9.5% and the accuracy ranged from −3.8% to 6.5%. The reliable method was successfully applied to the pharmacokinetics and tissue distribution studies of 6258-70 after intravenous administration in rats. The pharmacokinetic results indicated that the pharmacokinetic behavior of 6258-70 in rats was in accordance with linear features within tested dosage of 1 to 4 mg/kg, and there was no significant difference between the two genders. The tissue distribution study showed that 6258-70 had an effective penetration, spread widely and rapidly and could cross blood-brain barrier. The results of pharmacokinetics and tissue distribution may provide a guide for future study.

  7. PEEK tube-based online solid-phase microextraction-high-performance liquid chromatography for the determination of yohimbine in rat plasma and its application in pharmacokinetics study.

    Science.gov (United States)

    Xiang, Xiaowei; Shang, Bing; Wang, Xiaozheng; Chen, Qinhua

    2017-04-01

    Yohimbine is a novel compound for the treatment of erectile dysfunction derived from natural products, and pharmacokinetic study is important for its further development as a new medicine. In this work, we developed a novel PEEK tube-based solid-phase microextraction (SPME)-HPLC method for analysis of yohimbine in plasma and further for pharmacokinetic study. Poly (AA-EGDMA) was synthesized inside a PEEK tube as the sorbent for microextraction of yohimbine, and parameters that could influence extraction efficiency were systematically investigated. Under optimum conditions, the PEEK tube-based SPME method exhibits excellent enrichment efficiency towards yohimbine. By using berberine as internal standard, an online SPME-HPLC method was developed for analysis of yohimbine in human plasma sample. The method has wide linear range (2-1000 ng/mL) with an R 2 of 0.9962; the limit of detection was determined and was as low as 0.1 ng/mL using UV detection. Finally, a pharmacokinetic study of yohimbine was carried out by the online SPME-HPLC method and the results have been compared with those of reported methods. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Simultaneous determination of borneol and its metabolite in rat plasma by GC–MS and its application to pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Xiu-Man Sun

    2014-10-01

    Full Text Available A gas chromatography mass spectrometry (GC–MS method has been developed and fully validated for the simultaneous determination of natural borneol (NB and its metabolite, camphor, in rat plasma. Following a single liquid–liquid extraction, the analytes were separated using an HP-5MS capillary column (0.25 mm×30 m×0.25 μm and analyzed by MS in the selected ion monitoring mode. Selected ion monitor (m/z of borneol, camphor and internal standard was 95, 95 and 128, respectively. Linearity, accuracy, precision and extraction recovery of the analytes were all satisfactory. The method was successfully applied to pharmacokinetic studies of NB after oral administration to Wistar rats. Keywords: Borneol, Camphor, Simultaneous determination, Pharmacokinetics, GC–MS

  9. Simultaneous Determination of 11 Compounds in Gualou Guizhi Granule and Pharmacokinetics Study by UPLC-MS/MS

    Directory of Open Access Journals (Sweden)

    Chengtao Sun

    2017-01-01

    Full Text Available A rapid and sensitive ultrafast performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS was developed for the simultaneous determination of 11 compounds in Gualou Guizhi Granule (GLGZG, including liquiritin, isoliquiritin, liquirtin apioside, isoliquiritin apioside, liquiritigenin, isoliquiritigenin, glycyrrhizic acid, glycyrrhetinic acid, paeoniflorin, albiflorin, and paeoniflorin sulfonate in rat plasma. UPLC-MS/MS assay with negative ion mode was performed on a Waters CORTECS C18 (2.1 × 100 mm, 1.6 μm with the mobile phase consisting of 0.1% aqueous formic acid (A and acetonitrile (B in gradient elution at a flow rate of 0.25 mL·min−1. The method was linear for all analytes within the detection range (r≥0.9597. The inter- and intraday precision (RSD were 2.21–6.41% and 1.67–6.18%; the inter- and intraday accuracy (recover were 92.48–114.03% and 90.23–112.04%. And the recovery rate ranged from 81.30% to 108.22%. The matrix effect values obtained for analytes ranged from 88.91% to 113.32%. This validated method was successfully applied to a pharmacokinetics study in rats after oral administration of GLGZG.

  10. Interaction study of aspirin or clopidogrel on pharmacokinetics of donepezil hydrochloride in rats by HPLC-fluorescence detection.

    Science.gov (United States)

    Wada, Mitsuhiro; Nishiwaki, Junichiro; Yamane, Tomoko; Ohwaki, Yuichi; Aboul-Enein, Hassan Y; Nakashima, Kenichiro

    2007-06-01

    The present study aims to investigate the possibility of interaction of aspirin (Asp) or clopidogrel (CG) on donepezil (DP) hydrochloride in rats by HPLC-fluorescence detection. The separation of DP was achieved in ca. 13 min without interference of Asp and CG on the chromatogram. DP levels in rat plasma with a single administration of DP (5 mg/kg, i.p., group I) and those with a co-administration of Asp (200 mg/kg, p.o., group II or 200 mg/kg, i.p., group III) or CG (5 mg/kg, p.o., group IV) were monitored. The DP concentrations determined in rat plasma ranged from 25.0 to 336.1 ng/mL. Pharmacokinetic parameters for these groups were calculated and compared with one another. No significant difference was observed on the comparison of group I with other groups except for the mean resident time of group IV (p = 0.012). These basic findings may help clinical inference when DP is co-administered with Asp and CG to human. Copyright 2007 John Wiley & Sons, Ltd.

  11. Integrated identification, qualification and quantification strategy for pharmacokinetic profile study of Guizhi Fuling capsule in healthy volunteers.

    Science.gov (United States)

    Zhong, Yun-Xi; Jin, Xiao-Liang; Gu, Shi-Yin; Peng, Ying; Zhang, Ke-Rong; Ou-Yang, Bing-Chen; Wang, Yu; Xiao, Wei; Wang, Zhen-Zhong; Aa, Ji-Ye; Wang, Guang-Ji; Sun, Jian-Guo

    2016-08-16

    Guizhi Fuling capsule (GZFL), a traditional Chinese medicine formulation, is widely used in China to relieve pain from dysmenorrhea and is now in a Phase II clinical trial in the USA. Due to the low exposure of the five main medicative ingredients (amygdalin, cinnamic acid, gallic acid, paeoniflorin and paeonol) of GZFL in human, a strategy was built to qualitatively and quantitatively identify the possible metabolites of GZFL and to describe the pharmacokinetic profiles of GZFL in human. In this strategy, LC-Q-TOF/MS was used to identify and structurally elucidate the possible metabolites of GZFL in vivo; and a time-based metabolite-confirming step (TBMCs) was used to confirm uncertain metabolites. The simultaneously quantitation results by LC-MS/MS showed low exposure of the five medicative ingredients. According to the strategy we built, a total of 36 metabolites were found and structurally elucidated. The simultaneously semi-quantitative analysis by LC-MS/MS showed that obvious time-concentration curves could be established for 12 of the metabolites, and most of them showed a relatively higher exposure. This study provides a better understanding of the metabolic processes of GZFL in human.

  12. Propionyl-l-carnitine: Labelling in the N-methyl position with Carbon-11 and pharmacokinetic studies in rats

    International Nuclear Information System (INIS)

    Davenport, Raymond J.; Law, Marilyn P.; Pike, Victor W.; Osman, Safiye; Poole, Keith G.

    1995-01-01

    The prospective therapeutic, propionyl-l-carnitine, was labelled in the N-methyl position with the positron-emitter, carbon-11 (t (1(2)) = 20.4 min), with a view to studying its pharmacokinetics in humans using PET. Labelling was achieved by methylating nor-propionyl-l-carnitine hydrochloride with no-carrier-added [ 11 C]iodomethane (produced from cyclotron-produced [ 11 C]carbon dioxide) in ethanol in the presence of 1,2,2,6,6,-pentamethylpiperidine. HPLC of the reaction mixture on a strong cation exchange column provided high purity [N-methyl- 11 C]propionyl-l-carnitine in 62% radiochemical yield (decay-corrected from [ 11 C]iodomethane), ready for intravenous administration within 35 min from the end of radionuclide production. [N-methyl- 11 C]Propionyl-l-carnitine, given intravenously to rats, cleared rapidly from plasma. A slow uptake of radioactivity into myocardium and striated muscle was observed. In plasma, unchanged tracer represented 84% of the radioactivity at 2.5 min and 2.5% of the radioactivity at 60 min. In heart, unchanged tracer represented 18% of radioactivity at 2.5 min and 2.4% at 15 min. The remainder of radioactivity detected in plasma and heart was identified as [N-methyl- 11 C]l-carnitine and [N-methyl- 11 C]acetyl-l-carnitine

  13. Rapid and sensitive analysis of cyclobenzaprine by LC–MS/MS: Application to a pharmacokinetic study of cyclobenzaprine in dog

    Directory of Open Access Journals (Sweden)

    Wenhong Yu

    2014-04-01

    Full Text Available A rapid and sensitive liquid chromatography–tandem mass spectrometry method was developed and validated for the quantification of cyclobenzaprine in dog plasma. After extracted with organic solvent, post-treatment samples were separated on an Agela C18 column interfaced with a triple quadrupole tandem mass spectrometer in positive electrospray ionization mode. Multiple reaction monitoring was performed using the transitions of m/z 276.2 → 216.1 and m/z 325.1 → 109.0 to quantify cyclobenzaprine and escitalopram (internal standard, respectively. The mobile phase consisted of acetonitrile: 5 mM ammonium acetate: formic acid (90:10:0.01, v/v/v at a flow rate of 0.3 ml/min. The total analysis time was 2.4 min. The method was linear over the concentration range of 0.0200–10.0 ng/ml. The intra- and inter-day precision was within 12.8% in terms of relative standard deviation (RSD% and the accuracy within 5.6% in terms of relative error. This method was successfully applied in a pharmacokinetic study of extended-release cyclobenzaprine in dogs.

  14. Rapid and sensitive analysis of melatonin by LC-MS/MS and its application to pharmacokinetic study in dogs

    Directory of Open Access Journals (Sweden)

    Huimin Zhao

    2016-04-01

    Full Text Available A rapid and sensitive liquid chromatography tandem mass spectrometry method was established and validated for determination of melatonin in dog plasma using desvenlafaxine as an internal standard (IS. Plasma samples were pretreated by liquid–liquid extraction with ethyl acetate. Chromatographic separation was carried out on a C18 column at a flow rate of 0.2 ml/min by an isocratic mobile phase of methanol : 5 mM ammonium acetate : formic acid (40:60:0.1, v/v/v. Positive ion mode detection was performed using multiple reaction monitoring (MRM at m/z 233.2→174.2 for melatonin and m/z 264.2→58.2 for desvenlafaxine. The method was linear in the concentration range of 0.020–10 ng/ml with a correlation coefficient ≥0.996. The intra- and inter-assay precision (%RSD values were within 12.6% (LLOQ 15.2%, and accuracy (%RE ranged from −1.8% to 5.0% (LLOQ ±16.5%. The total analysis time was 3.0 min. The method was fully validated and successfully applied to a pharmacokinetic study of melatonin prolonged-release tablet in Beagle dogs. The values of half-life and Tmax were similar to the corresponding data reported before.

  15. A phase 1 study to evaluate effect of food on veliparib pharmacokinetics and relative bioavailability in subjects with solid tumors.

    Science.gov (United States)

    Mostafa, Nael M; Chiu, Yi-Lin; Rosen, Lee S; Bessudo, Alberto; Kovacs, Xenia; Giranda, Vincent L

    2014-09-01

    A phase 1 study was conducted to evaluate the bioavailability and food effect of a new veliparib formulation in subjects with solid tumors. Subjects (planned: Stage I, N = 20; Stage II, N = 16) received four regimens of a single oral dose of veliparib utilizing a group-sequential design. Subjects were administered single doses of 40 mg veliparib supplied as four 10 mg current formulation, four 10 mg new formulation and one 40 mg new formulation under fasting conditions and under non-fasting conditions. Serial blood samples were collected for the determination of veliparib pharmacokinetics. At the end of Stage I, the relative bioavailability between each pair of regimens was assessed by a two one-sided tests procedure from the analyses of the natural logarithms of C(max) and AUC. A 92.7 % confidence interval within the 0.80-1.25 range between each regimen pair determined bioequivalence. Four 10 mg current formulation capsules, four 10 mg new formulation and one 40 mg new formulation were bioequivalent with respect to C(max) and AUC under fasting conditions. The administration of a high-fat meal did not have a significant effect on AUC and only caused a slight decrease in veliparib C(max) (17 %) and a delay of approximately 1 h in T(max). The 40 mg new capsule was bioequivalent to currently used formulation. Food had no effect on the extent of veliparib absorption and only a small (17 %) decrease in peak exposure of veliparib.

  16. Rapid Determination of Imatinib in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry: Application to a Pharmacokinetic Study

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jeong Soo; Cho, Eun Gi; Huh, Wooseong; Ko, Jaewook; Jung, Jin Ah; Lee, Sooyoun [Samsung Medical Center, Seoul (Korea, Republic of)

    2013-08-15

    A simple, fast and robust analytical method was developed to determine imatinib in human plasma using liquid chromatography-tandem mass spectrometry with electrospray ionization in the positive ion mode. Imatinib and labeled internal standard were extracted from plasma with a simple protein precipitation. The chromatographic separation was performed using an isocratic elution of mobile phase involving 5.0 mM ammonium formate in water -5.0 mM ammonium formate in methanol (30:70, v/v) over 3.0 min on reversed-stationary phase. The detection was performed using a triple-quadrupole tandem mass spectrometer in multiple-reaction monitoring mode. The developed method was validated with lower limit of quantification of 10 ng/mL. The calibration curve was linear over 10-2000 ng/mL (R{sup 2} > 0.99). The method validation parameters met the acceptance criteria. The spiked samples and standard solutions were stable under conditions for storage and handling. The reliable method was successfully applied to real sample analyses and thus a pharmacokinetic study in 27 healthy Korean male volunteers.

  17. Determination of cyclovirobuxine D in human plasma by liquid chromatography tandem mass spectrometry and application in a pharmacokinetic study

    Directory of Open Access Journals (Sweden)

    Ling-li Mu

    2011-10-01

    Full Text Available A sensitive and reliable method based on liquid chromatography tandem mass spectrometry (LC–MS/MS for the quantitation of cyclovirobuxine D in human plasma has been developed and validated. Sample preparation by solid phase extraction was followed by separation on a CN column with a mobile phase of methanol–water (95:5, v/v containing 0.2% formic acid. Mass spectrometric detection in the positive ion mode was carried out by selected reaction monitoring (SRM of the transitions at m/z 403.0→372.0 for cyclovirobuxine D and m/z 325.0→234.0 for citalopram (internal standard. The method was linear in the range 10–200 ng/L with LLOQ of 10 ng/L, recovery >85%, and no significant matrix effects. Intra- and inter-day precisions were all <9% with accuracies of 94.0–104.8%. The method was successfully applied to a pharmacokinetic study involving a single oral administration of a 2 mg cyclovirobuxine D tablet to twenty-two healthy Chinese volunteers.

  18. Determination of fenticonazole in human plasma by HPLC–MS/MS and its application to pharmacokinetic studies

    Directory of Open Access Journals (Sweden)

    Weixing Mao

    2017-02-01

    Full Text Available Two simple and sensitive high performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS methods were developed and validated for the determination of fenticonazole in human plasma after percutaneous and intravaginal administration. Mifepristone was used as an internal standard (IS, and simple protein precipitation by acetonitrile containing 2% acetic acid was utilized for extracting the analytes from the plasma samples. Chromatographic separation was performed on a Kinetex XB-C18 column. The quantitation was performed by a mass spectrometer equipped with an electrospray ionization source in multiple reactions monitoring (MRM positive ion mode using precursor-to-product ion transitions of m/z 455.2–199.1 for fenticonazole and m/z 430.2–372.3 for mifepristone. The validated linear ranges were 5–1000 pg/mL and 0.1–20 ng/mL fenticonazole in plasma for the methods A and B, respectively. For the two methods, the accuracy data ranged from 85% to 115%, the intra- and inter-batch precision data were less than 15%, the recovery data were more than 90%, and no matrix interference was observed. The methods A and B were successfully validated and applied to the pharmacokinetic studies of fenticonazole gel in Chinese healthy volunteers after percutaneous and intravaginal administration, respectively.

  19. Arylpiperazines for management of benign prostatic hyperplasia: design, synthesis, quantitative structure-activity relationships, and pharmacokinetic studies.

    Science.gov (United States)

    Sarswat, Amit; Kumar, Rajeev; Kumar, Lalit; Lal, Nand; Sharma, Smriti; Prabhakar, Yenamandra S; Pandey, Shailendra K; Lal, Jawahar; Verma, Vikas; Jain, Ashish; Maikhuri, Jagdamba P; Dalela, Diwakar; Kirti; Gupta, Gopal; Sharma, Vishnu L

    2011-01-13

    A series of 27 aryl/heteroaryl/aralkyl/aroyl piperazines were synthesized, and most of these compounds reduced prostate weight of mature rats by 15-47%. Three compounds, 10, 12, and 18, had better activity profile (reduced prostate weight by 47%, 43%, and 39%, respectively) than the standard drug flutamide (24% reduction). QSAR suggested structures with more cyclic and branched moieties, increased topological separation of O and N therein, and reduced solvation connectivity index for better activity. Pharmacokinetic study with compound 10 at an oral dose of 10.0 mg/kg indicated good absorption, negligible extrahepatic elimination, and rapid distribution to the target organ (prostate) but restricted entry through the blood-brain barrier. A 10-fold decrease in PSA and 15-fold increase in ER-β gene expressions of human prostate cancer cells (LNCaP) by compound 10 in vitro indicated AR and ER-β mediated actions. The findings may stimulate further explorations of identified lead for the management of benign prostatic hyperplasia.

  20. Novel atomic absorption spectrometric and rapid spectrophotometric methods for the quantitation of paracetamol in saliva: application to pharmacokinetic studies.

    Science.gov (United States)

    Issa, M M; Nejem, R M; El-Abadla, N S; Al-Kholy, M; Saleh, Akila A

    2008-01-01

    A novel atomic absorption spectrometric method and two highly sensitive spectrophotometric methods were developed for the determination of paracetamol. These techniques based on the oxidation of paracetamol by iron (III) (method I); oxidation of p-aminophenol after the hydrolysis of paracetamol (method II). Iron (II) then reacts with potassium ferricyanide to form Prussian blue color with a maximum absorbance at 700 nm. The atomic absorption method was accomplished by extracting the excess iron (III) in method II and aspirates the aqueous layer into air-acetylene flame to measure the absorbance of iron (II) at 302.1 nm. The reactions have been spectrometrically evaluated to attain optimum experimental conditions. Linear responses were exhibited over the ranges 1.0-10, 0.2-2.0 and 0.1-1.0 mug/ml for method I, method II and atomic absorption spectrometric method, respectively. A high sensitivity is recorded for the proposed methods I and II and atomic absorption spectrometric method value indicate: 0.05, 0.022 and 0.012 mug/ml, respectively. The limit of quantitation of paracetamol by method II and atomic absorption spectrometric method were 0.20 and 0.10 mug/ml. Method II and the atomic absorption spectrometric method were applied to demonstrate a pharmacokinetic study by means of salivary samples in normal volunteers who received 1.0 g paracetamol. Intra and inter-day precision did not exceed 6.9%.

  1. Coformer selection in pharmaceutical cocrystal development: a case study of a meloxicam aspirin cocrystal that exhibits enhanced solubility and pharmacokinetics.

    Science.gov (United States)

    Cheney, Miranda L; Weyna, David R; Shan, Ning; Hanna, Mazen; Wojtas, Lukasz; Zaworotko, Michael J

    2011-06-01

    Meloxicam is a nonsteroidal anti-inflammatory drug with low aqueous solubility and high permeability. Because of its low solubility under acidic conditions (e.g., pH 1-5), it can take more than 2 h for meloxicam to reach its therapeutic concentration in humans. Although the slow onset of meloxicam does not necessarily impact the current label indications, the slow onset does prevent meloxicam from its potential application for the relief of mild-to-medium-level acute pain. Pharmaceutical cocrystallization of meloxicam, which represents a promising approach to generate diverse novel crystal forms, could be used to improve the aqueous solubility and accelerate the onset of action. In this contribution, we describe how a novel method can be used for coformer selection to enable the efficient and effective development of a pharmaceutical cocrystal with desired physicochemical and pharmacokinetic properties. Aspirin was selected as the coformer for meloxicam based upon this alternative route, which combines the supramolecular synthon approach with findings in the previous pharmacological and toxicological studies of meloxicam. The resulting cocrystal of meloxicam and aspirin exhibited superior kinetic solubility and possessed the potential to significantly decrease the time required to reach the human therapeutic concentration compared with the parent drug, meloxicam. Copyright © 2010 Wiley-Liss, Inc.

  2. Syntheses of therapeutically active labelled molecules for metabolic and pharmacokinetic studies. Synthesis, preservation and radiochemical purity problems

    International Nuclear Information System (INIS)

    Pichat, L.

    1977-01-01

    Molecules labelled with radioactive isotopes are without question an essential tool for metabolic and pharmacokinetic studies. Carbon 14 is often preferred to tritium since it allows better observation of the fate of carbonated structures. The fact that 14 CO 2 alone is used as basic material is the distinguishing feature of syntheses with isotopic carbon. In many cases the synthesis schemes of labelled drugs diverge considerably or entirely from those normally adopted for the unlabelled product. It is usually necessary to work on micro-quantities in order to maintain high specific activities, which implies the use of special synthesis techniques and of chromatographic separation and purification methods. Radiochemical purity tests are carried out by thin layer, column and gas phase chromatography, purity and identity checks by mass spectrometry and by 13 C and proton RMN. Labelled products are radiolysed by interaction of excited species with the molecules of the compound, a phenomenon much faster with tritiated than with 14 C-labelled molecules. The radiolysis rates may be reduced by molecule dilution. For ethical reasons it is not convenient to use 14 C molecules in human experiments, but molecular labelled with stable isotopes ( 13 C, 15 N, D) can serve instead [fr

  3. Quantification of nimesulide in human plasma by high-performance liquid chromatography with ultraviolet detector (HPLC-UV): application to pharmacokinetic studies in 28 healthy Korean subjects.

    Science.gov (United States)

    Kim, Mi-Sun; Park, Yoo-Sin; Kim, Shin-Hee; Kim, Sang-Yeon; Lee, Min-Ho; Kim, Youn-Hee; Kim, Do-Wan; Yang, Seok-Chul; Kang, Ju-Seop

    2012-05-01

    Nimesulide is a selective COX-2 inhibitor that is as effective as the classical non-acidic nonsteroidal anti-inflammatory drugs in the relief of various pain and inflammatory conditions, but is better tolerated with lower incidences of adverse effects than other drugs. After oral dose of 100 mg nimesulide to western subjects, a mean maximal concentration (C(max)) of 2.86 ∼ 6.5 µg/mL was reached at 1.22 ∼ 2.75 h and mean t(1/2β) of 1.8 ∼ 4.74 h. This study developed a robust method for quantification of nimesulide for the pharmacokinetics and suitability of its dosage in Korea and compared its suitability with other racial populations. Nimesulide and internal standard were extracted from acidified samples with methyl tert-butyl ether and analyzed by high-performance liquid chromatography with ultraviolet detection (HPLC-UV). The 28 healthy volunteers took 2 tablets of 100 mg nimesulide and blood concentrations were analyzed during the 24 h post dose. Several pharmacokinetic parameters were represented: AUC(0-infinity) = 113.0 mg-h/mL, C(max) = 12.06 mg/mL, time for maximal concentrations (T(max)) = 3.19 h and t(1/2β) = 4.51 h. These were different from those of western populations as follows: AUC was 14.5% and C(max) was 28% that of of Korean subjects and T(max) and t(1/2β) were also different. The validated HPLC-UV method was successfully applied for the pharmacokinetic studies of nimesulide in Korean subjects. Because the pharmacokinetics of nimesulide were different from western populations, its dosage regimen needs to be adjusted for Koreans. © The Author [2012]. Published by Oxford University Press. All rights reserved.

  4. Effects of haloperidol and cocaine pretreatments on brain distribution and kinetics of [{sup 11}C]methamphetamine in methamphetamine sensitized dog: Application of PET to drug pharmacokinetic study

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Hitoshi; Hishinuma, Takanori; Tomioka, Yoshihisa; Ishiwata, Shunji; Ido, Tatsuo; Iwata, Ren; Funaki, Yoshihito; Itoh, Masatoshi; Fujiwara, Takehiko; Yanai, Kazuhiko; Sato, Mitsumoto; Numachi, Yohtaro; Yoshida, Sumiko; Mizugaki, Michinao

    1997-02-01

    Repeated administration of methamphetamine (MAP) causes behavioral sensitization in animals. We previously reported that the maximum accumulation level of [{sup 11}C]MAP in the MAP-sensitized dog brain was 1.4 times higher than that in the control. In behavioral studies, haloperidol (a dopamine D{sub 2} receptor antagonist) prevents MAP-induced behavioral sensitization, and cocaine (a dopamine reuptake blocker) has the cross-behavioral sensitization with MAP. In the present study, to elucidate the relation between the MAP-induced behavioral sensitization and the pharmacokinetics of MAP, we investigated the effects of haloperidol and cocaine pretreatments on brain regional distribution and kinetics of [{sup 11}C]MAP using positron emission tomography (PET). A significant increase of [{sup 11}C]MAP uptake into the sensitized dog brain was prevented by haloperidol and cocaine pretreatments. These pharmacokinetic changes were not due to the changes in the rate of MAP metabolism. These results suggest haloperidol and cocaine can change the cerebral pharmacokinetic profile of MAP in the behavioral-sensitized dog. The variations of MAP-accumulation may affect the development or expression of MAP-induced behavioral sensitization.

  5. Effects of haloperidol and cocaine pretreatments on brain distribution and kinetics of [11C]methamphetamine in methamphetamine sensitized dog: Application of PET to drug pharmacokinetic study

    International Nuclear Information System (INIS)

    Nakamura, Hitoshi; Hishinuma, Takanori; Tomioka, Yoshihisa; Ishiwata, Shunji; Ido, Tatsuo; Iwata, Ren; Funaki, Yoshihito; Itoh, Masatoshi; Fujiwara, Takehiko; Yanai, Kazuhiko; Sato, Mitsumoto; Numachi, Yohtaro; Yoshida, Sumiko; Mizugaki, Michinao

    1997-01-01

    Repeated administration of methamphetamine (MAP) causes behavioral sensitization in animals. We previously reported that the maximum accumulation level of [ 11 C]MAP in the MAP-sensitized dog brain was 1.4 times higher than that in the control. In behavioral studies, haloperidol (a dopamine D 2 receptor antagonist) prevents MAP-induced behavioral sensitization, and cocaine (a dopamine reuptake blocker) has the cross-behavioral sensitization with MAP. In the present study, to elucidate the relation between the MAP-induced behavioral sensitization and the pharmacokinetics of MAP, we investigated the effects of haloperidol and cocaine pretreatments on brain regional distribution and kinetics of [ 11 C]MAP using positron emission tomography (PET). A significant increase of [ 11 C]MAP uptake into the sensitized dog brain was prevented by haloperidol and cocaine pretreatments. These pharmacokinetic changes were not due to the changes in the rate of MAP metabolism. These results suggest haloperidol and cocaine can change the cerebral pharmacokinetic profile of MAP in the behavioral-sensitized dog. The variations of MAP-accumulation may affect the development or expression of MAP-induced behavioral sensitization

  6. Single-dose safety and pharmacokinetic evaluation of fluorocoxib A: pilot study of novel cyclooxygenase-2-targeted optical imaging agent in a canine model

    Science.gov (United States)

    Cekanova, Maria; Uddin, Md. Jashim; Legendre, Alfred M.; Galyon, Gina; Bartges, Joseph W.; Callens, Amanda; Martin-Jimenez, Tomas; Marnett, Lawrence J.

    2012-11-01

    We evaluated preclinical single-dose safety, pharmacokinetic properties, and specific uptake of the new optical imaging agent fluorocoxib A in dogs. Fluorocoxib A, N-[(5-carboxy-X-rhodaminyl)but-4-yl]-2-[1-(4-chlorobenzoyl)-5-methoxy-2-methyl-1H-indol-3-yl]acetamide, selectively binds and inhibits the cyclooxygenase-2 (COX-2) enzyme, which is overexpressed in many cancers. Safety pilot studies were performed in research dogs following intravenous (i.v.) administration of 0.1 and 1 mg/kg fluorocoxib A. Blood and urine samples collected three days after administration of each dose of fluorocoxib A revealed no evidence of toxicity, and no clinically relevant adverse events were noted on physical examination of exposed dogs over that time period. Pharmacokinetic parameters were assessed in additional research dogs from plasma collected at several time points after i.v. administration of fluorocoxib A using high-performance liquid chromatography analysis. The pharmacokinetic studies using 1 mg/kg showed a peak of fluorocoxib A (92±28 ng/ml) in plasma collected at 0.5 h. Tumor specific uptake of fluorocoxib A was demonstrated using a dog diagnosed with colorectal cancer expressing COX-2. Our data support the safe single-dose administration and in vivo efficacy of fluorocoxib A, suggesting a high potential for successful translation to clinical use as an imaging agent for improved tumor detection in humans.

  7. A model-based meta-analysis of monoclonal antibody pharmacokinetics to guide optimal first-in-human study design

    Science.gov (United States)

    Davda, Jasmine P; Dodds, Michael G; Gibbs, Megan A; Wisdom, Wendy; Gibbs, John P

    2014-01-01

    The objectives of this retrospective analysis were (1) to characterize the population pharmacokinetics (popPK) of four different monoclonal antibodies (mAbs) in a combined analysis of individual data collected during first-in-human (FIH) studies and (2) to provide a scientific rationale for prospective design of FIH studies with mAbs. The data set was composed of 171 subjects contributing a total of 2716 mAb serum concentrations, following intravenous (IV) and subcutaneous (SC) doses. mAb PK was described by an open 2-compartment model with first-order elimination from the central compartment and a depot compartment with first-order absorption. Parameter values obtained from the popPK model were further used to generate optimal sampling times for a single dose study. A robust fit to the combined data from four mAbs was obtained using the 2-compartment model. Population parameter estimates for systemic clearance and central volume of distribution were 0.20 L/day and 3.6 L with intersubject variability of 31% and 34%, respectively. The random residual error was 14%. Differences (> 2-fold) in PK parameters were not apparent across mAbs. Rich designs (22 samples/subject), minimal designs for popPK (5 samples/subject), and optimal designs for non-compartmental analysis (NCA) and popPK (10 samples/subject) were examined by stochastic simulation and estimation. Single-dose PK studies for linear mAbs executed using the optimal designs are expected to yield high-quality model estimates, and accurate capture of NCA estimations. This model-based meta-analysis has determined typical popPK values for four mAbs with linear elimination and enabled prospective optimization of FIH study designs, potentially improving the efficiency of FIH studies for this class of therapeutics. PMID:24837591

  8. Pharmacokinetics of labelled compounds with technetium-99m and samarium-153

    International Nuclear Information System (INIS)

    Borda O, L.B.; Torres L, M.N.

    1997-01-01

    The purpose of this investigation was to establish the different pharmacokinetics parameters of the main radiopharmaceuticals labeled with technetium-99m and samarium-153. These parameters could be subsequently used as reference to compare other products with the same use. Mathematical models and a computerized pharmacokinetic program were used to this purpose. A biodistribution study in quadruplicate and/or quintuplicate was conducted for each radiopharmaceutical, data was was obtained in injection dose percentages. The biodistribution study involved the injection of a predetermined dose of the radiopharmaceutical into animals (rats or mice), which were subsequently put away at different time intervals, removing the relevant organs. Activity in each organ was read by means of a well-type NaI scintillation counter, data obtained in activity counts was transformed into injection dose percentages. Based on these percentages, the mathematical model was constructed and the pharmacokinetic parameters were obtained using the computerized program Expo 2 v. 1, which is written in C language and works in windows. Analyzing the results obtained, we can conclude that the use of the Expo 2 v. 1 program for a bi compartmental analysis allowed us to obtain reliable pharmacokinetic parameters which describe what happens in the organism when the radiopharmaceutical passes from the central compartment to the peripheral one and vice versa

  9. Safety, efficacy and pharmacokinetics of neratinib (HKI-272) in Japanese patients with advanced solid tumors: a Phase 1 dose-escalation study.

    Science.gov (United States)

    Ito, Yoshinori; Suenaga, Mitsukuni; Hatake, Kiyohiko; Takahashi, Shunji; Yokoyama, Masahiro; Onozawa, Yusuke; Yamazaki, Kentaro; Hironaka, Shuichi; Hashigami, Kiyoshi; Hasegawa, Hirotaka; Takenaka, Nobuko; Boku, Narikazu

    2012-04-01

    Neratinib (HKI-272), a potent, irreversible, small-molecule, orally administered, pan-ErbB inhibitor that blocks signal transduction via inhibition of three epidermal growth factor receptors [ErbB1, ErbB2 (Her2) and ErbB4], is being developed for the treatment of solid tumors, including breast cancer. This Phase 1 dose-escalation study assessed the safety, tolerability, maximum-tolerated dose, antitumor activity and pharmacokinetics of neratinib in Japanese patients with advanced solid tumors. Patients received neratinib 80, 160, 240 or 320 mg orally; each patient enrolled in only one dose cohort. Patients received a single dose in week 1, followed by daily continuous doses. Blood samples collected were on days 1 and 21 for pharmacokinetic analyses. Twenty-one patients were enrolled (3 breast cancer; 17 colorectal cancer; 1 gastric cancer). Neratinib-related adverse events (all grades) included diarrhea (20 patients), fatigue (14 patients), nausea and abdominal pain (9 patients each) and anorexia (8 patients). Grade ≥3 neratinib-related adverse events in two or more patients were diarrhea and anorexia (two patients each). Dose-limiting toxicities were diarrhea and anorexia (two patients, 320 mg dose). The maximum-tolerated dose and recommended dose was neratinib 240 mg once daily. Of 21 evaluable patients, 2 with breast cancer had partial response, 3 had stable disease ≥24 weeks, 7 had stable disease ≥16 weeks and 9 had progressive disease. Pharmacokinetic analyses indicated that neratinib exposures increased with dose. The safety, efficacy and pharmacokinetic profiles of neratinib are consistent with those reported for non-Japanese patients and warrant further investigation of neratinib in Japanese patients with solid tumors.

  10. Pharmacokinetics and pharmacodynamics of medication in asphyxiated newborns during controlled hypothermia. The PharmaCool multicenter study

    Directory of Open Access Journals (Sweden)

    de Haan Timo R

    2012-05-01

    Full Text Available Abstract Background In the Netherlands, perinatal asphyxia (severe perinatal oxygen shortage necessitating newborn resuscitation occurs in at least 200 of the 180–185.000 newly born infants per year. International randomized controlled trials have demonstrated an improved neurological outcome with therapeutic hypothermia. During hypothermia neonates receive sedative, analgesic, anti-epileptic and antibiotic drugs. So far little information is available how the pharmacokinetics (PK and pharmacodynamics (PD of these drugs are influenced by post resuscitation multi organ failure and the metabolic effects of the cooling treatment itself. As a result, evidence based dosing guidelines are lacking. This multicenter observational cohort study was designed to answer the question how hypothermia influences the distribution, metabolism and elimination of commonly used drugs in neonatal intensive care. Methods/Design Multicenter cohort study. All term neonates treated with hypothermia for Hypoxic Ischemic Encephalopathy (HIE resulting from perinatal asphyxia in all ten Dutch Neonatal Intensive Care Units (NICUs will be eligible for this study. During hypothermia and rewarming blood samples will be taken from indwelling catheters to investigate blood concentrations of several antibiotics, analgesics, sedatives and anti-epileptic drugs. For each individual drug the population PK will be characterized using Nonlinear Mixed Effects Modelling (NONMEM. It will be investigated how clearance and volume of distribution are influenced by hypothermia also taking maturation of neonate into account. Similarly, integrated PK-PD models will be developed relating the time course of drug concentration to pharmacodynamic parameters such as successful seizure treatment; pain assessment and infection clearance. Discussion On basis of the derived population PK-PD models dosing guidelines will be developed for the application of drugs during neonatal hypothermia treatment. The

  11. Pharmacokinetics of serelaxin in patients with hepatic impairment: a single-dose, open-label, parallel group study.

    Science.gov (United States)

    Kobalava, Zhanna; Villevalde, Svetlana; Kotovskaya, Yulia; Hinrichsen, Holger; Petersen-Sylla, Marc; Zaehringer, Andreas; Pang, Yinuo; Rajman, Iris; Canadi, Jasna; Dahlke, Marion; Lloyd, Peter; Halabi, Atef

    2015-06-01

    Serelaxin is a recombinant form of human relaxin-2 in development for treatment of acute heart failure. This study aimed to evaluate the pharmacokinetics (PK) of serelaxin in patients with hepatic impairment. Secondary objectives included evaluation of immunogenicity, safety and tolerability of serelaxin. This was an open-label, parallel group study (NCT01433458) comparing the PK of serelaxin following a single 24 h intravenous (i.v.) infusion (30 μg kg(-1)  day(-1) ) between patients with mild, moderate or severe hepatic impairment (Child-Pugh class A, B, C) and healthy matched controls. Blood sampling and standard safety assessments were conducted. Primary non-compartmental PK parameters [including area under the serum concentration-time curve AUC(0-48 h) and AUC(0-∞) and serum concentration at 24 h post-dose (C24h )] were compared between each hepatic impairment group and healthy controls. A total of 49 subjects (including 25 patients with hepatic impairment) were enrolled, of which 48 subjects completed the study. In all groups, the serum concentration of serelaxin increased over the first few hours of infusion, reached steady-state at 12-24 h and then declined following completion of infusion, with a mean terminal half-life of 7-8 h. All PK parameter estimates were comparable between each group of patients with hepatic impairment and healthy controls. No serious adverse events, discontinuations due to adverse events or deaths were reported. No serelaxin treatment-related antibodies developed during this study. The PK and safety profile of serelaxin were not affected by hepatic impairment. No dose adjustment is needed for serelaxin treatment of 48 h i.v. infusion in patients with hepatic impairment. © 2014 The British Pharmacological Society.

  12. Electrosteric stealth Rivastigmine loaded liposomes for brain targeting: preparation, characterization, ex vivo, bio-distribution and in vivo pharmacokinetic studies.

    Science.gov (United States)

    Nageeb El-Helaly, Sara; Abd Elbary, Ahmed; Kassem, Mohamed A; El-Nabarawi, Mohamed A

    2017-11-01

    Being one of the highly effective drugs in treatment of Alzheimer's disease, Rivastigmine brain targeting is highly demandable, therefore liposomal dispersion of Rivastigmine was prepared containing 2 mol% PEG-DSPE added to Lecithin, Didecyldimethyl ammonium bromide (DDAB), Tween 80 in 1:0.02:0.25 molar ratio. A major challenge during the preparation of liposomes is maintaining a stable formulation, therefore the aim of our study was to increase liposomal stability by addition of DDAB to give an electrostatic stability and PEG-DSPE to increase stability by steric hindrance, yielding what we called an electrosteric stealth (ESS) liposomes. A medium nano-sized liposome (478 ± 4.94 nm) with a nearly neutral zeta potential (ZP, -8 ± 0.2 mV) and an entrapment efficiency percentage of 48 ± 6.22 was prepared. Stability studies showed no major alteration after three months storage period concerning particle size, polydispersity index, ZP, entrapment efficiency and in vitro release study confirming the successful formation of a stable liposomes. No histopathological alteration was recorded for ESS liposomes of the sheep nasal mucosa. While ESS liposomes showed higher % of drug permeating through the sheep nasal mucosa (48.6%) than the drug solution (28.7%). On completing the in vivo pharmacokinetic studies of 36 rabbits showed 424.2% relative bioavailability of the mean plasma levels of the formula ESS compared to that of RHT intranasal solution and 486% relative bioavailability of the mean brain levels.

  13. Pharmacokinetics of Botanical Drugs and Plant Extracts.

    Science.gov (United States)

    Dominguez More, Gina Paola; Cardenas, Paola Andrea; Costa, Geison M; Simoes, Claudia M O; Aragon, Diana Marcela

    2017-01-01

    Botanical drugs contain plant extracts, which are complex mixtures of compounds. As with conventional drugs, it is necessary to validate their efficacy and safety through preclinical and clinical studies. However, pharmacokinetic studies for active constituents or characteristic markers in botanical drugs are rare. The objective of this review was to investigate the global state of the art in pharmacokinetic studies of active ingredients present in plant extracts and botanical drugs. A review of pharmacokinetics studies of chemical constituents of plant extracts and botanical drugs was performed, with a total of 135 studies published between January 2004 and February 2015 available in recognized scientific databases. Botanical preparations were mainly found in the form of aqueous extracts of roots and rhizomes. The most widely studied species was Salvia miltiorrhiza Bunge, and the compound most frequently used as a pharmacokinetic marker was berberine. Most studies were performed using the Sprague Dawley rat model, and the preparations were mainly administered orally in a single dose. Quantification of plasma concentrations of pharmacokinetic markers was performed mainly by liquid-liquid extraction, followed by high performance liquid chromatography coupled to mass spectrometry detector. In conclusion, in recent years there has been an increasing interest among researchers worldwide in the study of pharmacokinetics of bioactive compounds in botanical drugs and plant extracts, especially those from the Traditional Chinese Medicine. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Phase I and pharmacokinetic study of the combination of topotecan and ifosfamide administered intravenously every 3 weeks

    NARCIS (Netherlands)

    Kerbusch, T.; Groenewegen, G.; Mathôt, R. A. A.; Herben, V. M. M.; ten Bokkel Huinink, W. W.; Swart, M.; Ambaum, B.; Rosing, H.; Jansen, S.; Voest, E. E.; Beijnen, J. H.; Schellens, J. H. M.

    2004-01-01

    To determine the maximum-tolerated dose (MTD), dose-limiting toxicities, and pharmacokinetics of topotecan administered as a 30-min intravenous (i.v.) infusion over 5 days in combination with a 1-h i.v. infusion of ifosfamide (IF) for 3 consecutive days every 3 weeks. Patients with advanced

  15. Dose-finding and pharmacokinetic study of cisplatin, gemcitabine, and SU5416 in patients with solid tumors

    NARCIS (Netherlands)

    Kuenen, Bart C.; Rosen, Lee; Smit, Egbert F.; Parson, Mandy R. N.; Levi, Marcel; Ruijter, Rita; Huisman, Holger; Kedde, Marc A.; Noordhuis, Paul; van der Vijgh, Wim J. F.; Peters, Godefridus J.; Cropp, Gillian F.; Scigalla, Paul; Hoekman, Klaus; Pinedo, Herbert M.; Giaccone, Giuseppe

    2002-01-01

    Purpose: To investigate the feasibility and pharmacokinetics of the combination cisplatin, gemcitabine, and SU5416. Patients and Methods: Patients received cisplatin 80 mg/m(2) on day 1, gemcitabine 1,250 mg/m(2) on days 1 and 8, repeated every 3 weeks, and SU5416 (85 and 145 mg/m(2)) intravenously

  16. A Prospective Study of the Efficacy, Safety and Pharmacokinetics of Enteral Moxifloxacin in the Treatment of Hemodialysis Patients with Pneumonia.

    Science.gov (United States)

    Tokimatsu, Issei; Shigemura, Katsumi; Kotaki, Tomohiro; Yoshikawa, Hiroki; Yamamichi, Fukashi; Tomo, Tadashi; Arakawa, Soichi; Fujisawa, Masato; Kadota, Jun-Ichi

    2017-01-01

    Objectives To investigate the efficacy of oral moxifloxacin (MFLX) as a treatment for pneumonia in hemodialysis (HD) patients and the pharmacokinetic (PK) profile of MFLX after oral administration. Methods Thirteen adult patients who required HD due to chronic renal failure were enrolled in the present study, which was performed to investigate the treatment of community-acquired pneumonia in HD patients. A standard dose of MFLX (400 mg, once daily) was administered. The therapy was continued, discontinued, or switched to another antibiotic depending on the response of the pneumonia to MFLX. A population PK model was developed using the post-hoc method. Results In total, 13 HD patients with pneumonia (male, n=7; female, n=6) were enrolled in the present study. The evaluation on the 3rd day showed that treatment was successful in 11 patients (84.6%) and that 10 patients were cured (76.9%). In the one case in which MFLX treatment failed, the patient was cured by switching to ceftriaxone (CTRX) (2 g, intravenously) plus levofloxacin (LVFX) (250 mg, orally). The causative bacterium in this male patient was P. aeruginosa. It did not display resistance to fluoroquinolones. One patient had liver dysfunction due to MFLX. The estimated PK parameters of MFLX were as follows: AUC 0→24 , 61.04±17.74 μg h/mL; C max , 5.25±1.12 μg/mL; and C trough , 1.15±0.45 μg/mL. The PK parameters of MFLX among the patients in whom adverse events occurred or in whom a cure was not achieved did not differ from those of the other patients to a statistically significant extent. Conclusion MFLX showed good efficacy and safety in HD patients with community-acquired pneumonia and the results of the PK analysis were favorable. Further prospective studies with larger numbers of patients will be needed to draw definitive conclusions.

  17. A phase 1 randomized study evaluating the effect of omeprazole on the pharmacokinetics of a novel 5-hydroxytryptamine receptor 4 agonist, revexepride (SSP-002358, in healthy adults

    Directory of Open Access Journals (Sweden)

    Pierce D

    2015-02-01

    Full Text Available David Pierce,1 Mary Corcoran,2 Maria Velinova,3 Stuart Hossack,4 Mieke Hoppenbrouwers,5 Patrick Martin,21Shire, Basingstoke, UK; 2Shire, Wayne, PA, USA; 3PRA International, Zuidlaren, the Netherlands; 4Covance, Leeds, UK; 5Shire-Movetis NV, Turnhout, BelgiumBackground: About 30% of patients with gastroesophageal reflux disease continue to experience symptoms despite treatment with proton pump inhibitors. The 5-hydroxytryptamine 4 receptor agonist revexepride (SSP-002358 is a novel prokinetic that stimulates gastrointestinal motility, which has been suggested as a continued cause of symptoms in these patients. The aim of this study was to assess whether revexepride pharmacokinetics were affected by co-administration of omeprazole, in preparation for a proof-of-concept evaluation of revexepride added to proton pump inhibitor treatment.Methods: In this phase 1, open-label, randomized, two-period crossover study, healthy adults aged 18–55 years were given a single dose of revexepride 1 mg or revexepride 1 mg + omeprazole 40 mg. Pharmacokinetic parameters were assessed for up to 48 hours after administration of the investigational product. Adverse events, clinical chemistry and hematology parameters, electrocardiograms, and vital signs were monitored.Results: In total, 42 participants were enrolled and 40 completed the study. The median age was 24 years (18–54 years, 55% were women and 93% were white. The pharmacokinetic parameters of revexepride were similar without or with omeprazole co-administration. The mean area under the plasma concentration–time curve from time 0 to infinity (AUC0–∞ was 23.3 ng · h/mL (standard deviation [SD]: 6.33 ng · h/mL versus 24.6 ng · h/mL (SD: 6.31 ng · h/mL, and maximum plasma concentrations (Cmax were 3.89 ng/mL (SD: 1.30 ng/mL and 4.12 ng/mL (SD: 1.29 ng/mL in participants without and with omeprazole, respectively. For AUC0–∞ and Cmax, the 90% confidence intervals for the ratios of geometric least

  18. An HPLC tandem mass spectrometry for quantification of ET-26-HCl and its major metabolite in plasma and application to a pharmacokinetic study in rats.

    Science.gov (United States)

    Chen, Xu; Zhang, Wensheng; Rios, Sandy; Morkos, Miriam B; Ye, Xiaoli; Li, Gen; Jiang, Xuehua; Wang, Zhijun; Wang, Ling

    2018-02-05

    ET-26-HCl is a new analog of etomidate, a short-acting anesthetic drug, with less adrenal cortex inhibition. The pharmacokinetics of ET-26-HCl in rats needs to be determined for future clinical trials in human subjects. In order to facilitate the pharmacokinetic study, a liquid chromatography based tandem mass spectrometric (HPLC-MS/MS) method was developed and validated for quantification of ET-26-HCl and its major metabolite, ET-26-acid. These two compounds and gabapentin (internal standard) were extracted using a protein precipitation method with methanol and detected by Multiple Reaction Monitoring of m/z transition of 275.6-170.9, 217.7-113.1, and 172.5-154.3 for ET-26-HCl, ET-26-acid, and gabapentin respectively. This method was validated in terms of sensitivity, linearity, reproducibility, and stability. The HPLC-MS/MS method was found linear over the concentration ranges of 21.76-4352ng/mL, and 18.62-3724ng/mL with LLOQ of 21.76 and 18.62ng/mL for ET-26-HCl and ET-26-acid respectively. The mean intra-day and inter-day accuracy was between 94.11-107.78%, while the precision was within the limit of 15.0% for all the quality control samples. A pharmacokinetic study was then conducted in rats following intravenous injection of 2.1, 4.2, and 8.4mg/kg. The linear pharmacokinetics of ET-26-HCl was observed over the dose range of 2.1-8.4mg/kg. The average terminal phase elimination half-lives were 0.87 and 1.03h for ET-26-HCl and ET-26-acid respectively. In summary, an HPLC-MS/MS method for quantification of ET-26-HCl in rat plasma has been developed and successfully applied to a pharmacokinetic study. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Proteomic study on gender differences in aging kidney of mice

    Directory of Open Access Journals (Sweden)

    Cristobal Susana

    2009-04-01

    Full Text Available Abstract Background This study aims to analyze sex differences in mice aging kidney. We applied a proteomic technique based on subfractionation, and liquid chromatography coupled with 2-DE. Samples from male and female CD1-Swiss outbred mice from 28 weeks, 52 weeks, and 76 weeks were analysed by 2-DE, and selected proteins were identified by matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS. Results This proteomic analysis detected age-related changes in protein expression in 55 protein-spots, corresponding to 22 spots in males and 33 spots in females. We found a protein expression signature (PES of aging composed by 8 spots, common for both genders. The identified proteins indicated increases in oxidative and proteolytic proteins and decreases in glycolytic proteins, and antioxidant enzymes. Conclusion Our results provide insights into the gender differences associated to the decline of kidney function in aging. Thus, we show that proteomics can provide valuable information on age-related changes in expression levels of proteins and related modifications. This pilot study is still far from providing candidates for aging-biomarkers. However, we suggest that the analysis of these proteins could suggest mechanisms of cellular aging in kidney, and improve the kidney selection for transplantation.

  20. Pharmacokinetics of mitragynine in man

    Directory of Open Access Journals (Sweden)

    Trakulsrichai S

    2015-04-01

    Full Text Available Satariya Trakulsrichai,1,2 Korbtham Sathirakul,3,4 Saranya Auparakkitanon,5 Jatupon Krongvorakul,5 Jetjamnong Sueajai,5 Nantida Noumjad,5 Chonlaphat Sukasem,5 Winai Wananukul2,6 1Department of Emergency Medicine, Faculty of Medicine Ramathibodi Hospital, 2Ramathibodi Poison Center, Faculty of Medicine Ramathibodi Hospital, 3Department of Pharmacy, Faculty of Pharmacy, Mahidol University, Bangkok, Thailand; 4Center for Drug Research Discovery and Development, Thammasat Univerisity, Prathumthani, Thailand; 5Department of Pathology, Faculty of Medicine Ramathibodi Hospital, 6Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand Background: Kratom, known botanically as Mitragyna speciosa (Korth., is an indigenous tree in Southeast Asia. Kratom is currently easily available worldwide via special shops and the Internet to use as a drug of abuse, opioid alternative, or pain killer. So far, the pharmacokinetics of this plant has been studied only in animals, and there is no such study in humans. The major abundant active alkaloid in Kratom, mitragynine, is one of the promising new chemical substances to be developed as a new drug. The aim of this study was to examine the pharmacokinetics of mitragynine and assess the linearity in pharmacokinetics in chronic users.Methods: Since Kratom is illegal in Thailand, studies in healthy subjects would be unethical. We therefore conducted a prospective study by enrolling ten chronic, regular, healthy users. We adjusted the steady state in each subject by giving a known amount of Kratom tea for 7 days before commencement of the experiment. We admitted and gave different oral doses to subjects to confirm linearity in pharmacokinetics. The mitragynine blood concentrations at 17 times points and the urine concentrations during the 24-hour period were collected and measured by liquid chromatography-tandem mass spectrometry method. Results: Ten male subjects completed

  1. Pharmacokinetics and Safety Assessment of l-Tetrahydropalmatine in Cocaine Users: A Randomized, Double-Blind, Placebo-Controlled Study.

    Science.gov (United States)

    Hassan, Hazem E; Kelly, Deanna; Honick, Moshe; Shukla, Sagar; Ibrahim, Ahmed; Gorelick, David A; Glassman, Matthew; McMahon, Robert P; Wehring, Heidi J; Kearns, Ann Marie; Feldman, Stephanie; Yu, Mingming; Bauer, Ken; Wang, Jia Bei

    2017-02-01

    Cocaine use disorder (CUD) remains a significant public health challenge. l-Tetrahydropalmatine (l-THP), a well-tolerated and nonaddictive compound, shows promise for the management of CUD. Its pharmacologic profile includes blockade at dopamine and other monoamine receptors and attenuation of cocaine self-administration, reinstatement, and rewarding properties in rats. This study evaluated the safety of l-THP in human cocaine users and its influence on the safety and pharmacokinetics (PK) of cocaine. Twenty-four cocaine-using adult men were randomized to receive l-THP (30 mg twice a day orally) or placebo double-blind for 4 days, with an intranasal cocaine (40 mg) challenge on the fourth day. Safety and tolerability were evaluated using vital signs, ECG, clinical laboratory tests, and standardized self-report instruments. Peripheral venous blood was collected periodically and later assayed for l-THP and cocaine using highly sensitive and specific ultraperformance liquid chromatography-fluorescence detection (UPLC-FLD) methods. Twenty subjects completed the study, of whom 19 provided complete PK data. The short 3.5-day course of l-THP was safe and well tolerated and did not affect cocaine's PK or its acute cardiovascular effects. The cocaine AUC 0→∞ was 211.5 and 261.4 h·ng/mL, and the C max was 83.3 and 104.5 ng/mL for the l-THP and placebo groups, respectively. In addition there were no significant differences in the number of side effects reported in each group (l-THP group 22 [48%], placebo group 24 [52%]) or vital signs including, heart rate, blood pressure, complete blood count, or ECG. These findings suggest that oral THP has promise for further development as a treatment for CUD. © 2016, The American College of Clinical Pharmacology.

  2. Phase I clinical and pharmacokinetic study of S-1 plus oral leucovorin in patients with metastatic colorectal cancer.

    Science.gov (United States)

    Yoshino, Takayuki; Hyodo, Ichinosuke; Nishina, Tomohiro; Narahara, Hiroyuki; Sugimoto, Naotoshi; Yoshisue, Kunihiro; Boku, Narikazu

    2017-01-01

    S-1 has shown a response rate of 35% in chemonaïve patients with metastatic colorectal cancer (mCRC). Leucovorin enhances the antitumor activity of 5-fluorouracil, and concurrent oral administration of S-1 and leucovorin may represent a more active treatment option for mCRC. S-1 (35 mg/m 2 ) and leucovorin (25 mg/body) were orally administered twice daily to chemonaïve patients with mCRC. Predefined dose (schedule)-limiting toxicities (DLTs) during the first course and treatment continuity during the first two courses were evaluated during three periods of treatment with S-1 plus leucovorin (level 0, 2 weeks; level 1, 3 weeks; and level 2, 4 weeks), each followed by a 2-week rest. The pharmacokinetics (PK) of S-1 and leucovorin were studied on days 1 and 14 of the first course. Fifteen patients were enrolled. All three patients had DLTs at level 2, and this level was considered the maximum tolerated schedule. Level 0 was designated as the recommended schedule based on the incidences of DLTs and treatment continuity. The main toxic effects were gastrointestinal, such as diarrhea and stomatitis. There was no grade 4 adverse event or treatment-related death. The overall response rate was 67% (95% confidence interval, 38-88%). The PK profiles of S-1 plus leucovorin were similar to those in previous studies. The recommended schedule was 2 weeks of S-1 plus leucovorin followed by a 2-week rest. The increased response and gastrointestinal toxicities of S-1 plus leucovorin as compared with S-1 monotherapy suggest that co-administration of leucovorin enhanced the activity of S-1.

  3. UPLC–MS/MS for the determination of azilsartan in beagle dog plasma and its application in a pharmacokinetics study

    Directory of Open Access Journals (Sweden)

    Cheng Gong

    2015-06-01

    Full Text Available The purpose of the study is to develop an ultra performance liquid chromatography-tandem mass spectrometry (UPLC–MS/MS to determinate the concentration of azilsartan in the dog plasma. After precipitated by methanol, the plasma sample containing azilsartan and diazepam (internal standard, IS was determined by UPLC–MS/MS. The mobile phase consisted of acetonitrile-water was pumped at a flow rate of 0.3 ml/min in gradient elution. Kinetex 2.6 μ XB-C18 column (50 × 2.1 mm, 100 Å; Phenomenex, USA were used for LC separations. The column temperature was 30 °C and the injection volume was 5 μl. The electrospray ionization (ESI and multiple reaction monitoring (MRM were applied at the transitions of m/z 457 → 279 (azilsartan and m/z 285 → 193 (diazepam, respectively. The developed method was identified a good linearity over a concentration range of 2.5–5000 ng/ml. The lower limit of quantitation (LLOQ was 2.5 ng/ml. The intra-day and inter-day precision (relative standard deviation, RSD% were less than 10% and accuracy (relative error, RE % was less than 5% at three quality control levels. The extraction recovery of azilsartan at three quality control levels were 82.41 ± 0.68%, 98.66 ± 11.00%, 102.43 ± 0.82%. And the recovery for IS (100 ng/ml was 91.75 ± 0.54%. A validated UPLC–MS/MS method was firstly developed for the quantification of azilsartan in dog plasma and it was applied to the pharmacokinetics study.

  4. An Open-Label, Phase 1 Study to Assess the Effects of Hepatic Impairment on Pomalidomide Pharmacokinetics.

    Science.gov (United States)

    Li, Yan; Wang, Xiaomin; Liu, Liangang; Zhang, Chengyue; Gomez, Diana; Reyes, Josephine; Palmisano, Maria; Zhou, Simon

    2018-05-10

    Pomalidomide is an immunomodulatory drug and the dosage of 4 mg per day taken orally on days 1-21 of repeated 28-day cycles has been approved in the European Union and United States to treat patients with relapsed/refractory multiple myeloma. Because pomalidomide is extensively metabolized prior to excretion, a total of 32 subjects (8 healthy subjects in group 1; 8 subjects with severe hepatic impairment in group 2; 8 subjects with moderate hepatic impairment in group 3; and 8 subjects with mild hepatic impairment in group 4) were enrolled in a multicenter, open-label, single-dose study to assess the impact of hepatic impairment on pomalidomide exposure. Following administration of a single oral dose of 4-mg pomalidomide, the geometric mean ratios of pomalidomide total plasma exposures (AUC) were 171.5%, 157.5%, and 151.2% and the geometric mean ratios of pomalidomide plasma peak exposures (C max ) were 75.8%, 94.8%, and 94.2% for subjects with severe, moderate, or mild hepatic impairment, respectively, versus healthy subjects. Pomalidomide administered as a single oral 4-mg dose was safe and well tolerated by healthy subjects and subjects with severe, moderate, or mild hepatic impairment. Based on the pharmacokinetic results from this study, the pomalidomide prescribing information approved by the US Food and Drug Administration recommends for patients with mild or moderate hepatic impairment (Child-Pugh classes A or B), a 3-mg starting daily dose (25% dose reduction) and for patients with severe hepatic impairment (Child-Pugh class C), a 2-mg starting daily dose (50% dose reduction). © 2018 The Authors. Clinical Pharmacology in Drug Development Published by Wiley Periodicals, Inc. on behalf of The American College of Clinical Pharmacology.

  5. Can Saliva and Plasma Methadone Concentrations Be Used for Enantioselective Pharmacokinetic and Pharmacodynamic Studies in Patients With Advanced Cancer?

    Science.gov (United States)

    George, Rani; Haywood, Alison; Good, Phillip; Hennig, Stefanie; Khan, Sohil; Norris, Ross; Hardy, Janet

    2017-09-01

    Methadone is a potent analgesic used to treat refractory cancer pain. It is administered as a racemic mixture, with the l-enantiomer being primarily a μ-receptor agonist, whereas the d-enantiomer is an N-methyl-d-aspartate antagonist and inhibits serotonin and norepinephrine reuptake. Dose requirements vary greatly among patients to achieve optimal pain control and to avoid the risk of adverse effects. The relationship between plasma and saliva methadone enantiomer concentrations was investigated to determine if saliva could be a substitute for plasma in pharmacodynamic and pharmacokinetic studies for clinical monitoring and dose optimization of methadone in patients with advanced cancer. Patients with advanced cancer who were prescribed varying doses of oral methadone for pain management were recruited to obtain paired plasma and saliva samples. Pain scores were recorded at the time of sampling. The total and unbound plasma and saliva concentrations of the l- and d-enantiomers of methadone were quantified by using an HPLC-MS/MS method. The relationship between plasma (total and unbound) and saliva concentrations were compared. The saliva-to-plasma concentration ratio was compared versus the dose administered and the time after dosing for both enantiomers. The association of methadone concentrations with reported pain scores was compared by using a Mann-Whitney U test for significance. Fifty patients receiving a mean dose of 11mg/d of methadone provided 151 paired plasma and saliva samples. The median age of the population was 61 years with an interquartile range of 53-71 years with total body weight ranging from 59-88 kg. Median (interquartile) total plasma concentrations for l- and d-methadone were 50.78 ng/mL (30.6-113.0 ng/mL) and 62.0 ng/mL (28.7-116.0 ng/mL), respectively. Median (interquartile range) saliva concentrations for l- and d-methadone were 81.5 ng/mL (28.0-203.2 ng/mL) and 44.2 (16.2-149.7 ng/mL). No relationship could be established between

  6. Comparative study of intact A7 MoAc and F(ab')2 fragments for radioimmunoimaging of human colon cancer in nude mice

    International Nuclear Information System (INIS)

    Kojima, Shuji; Suzuki, Naomi; Shimura, Noriko; Kubodera, Akiko; Kubota, Kazuhiko; Yamaguchi, Toshiharu; Takahashi, Toshio; Oyamada, Hiyoshimaru

    1993-01-01

    Differences of pharmacokinetics and tumor imaging ability between intact monoclonal antibody A7 (A7 MoAb) and F(ab) 2 fragments were studied in human colon cancer (LS-174T)-bearing nude mice. The authors examined the yield and the immunoreactivity of F(ab) 2 fragments after treatment with ficin as a function of time. The yield of F(ab) 2 fragments reached about 50% after ficin treatment for 8 h, and the F(ab) 2 retained about 80% of the immunoreactivity of the corresponding MoAb. Longer digestion with ficin produced smaller fragments (less than 92 kDa) with a lower yield and most of the immunoreactivity was lost. In pharmacokinetics studies, the F(ab') 2 was preferentially taken up by the tumor, cleared more rapidly from the blood circulation and seemed to have less non-specific tissue binding than intact A7 MoAb. The tumor image obtained at an early time using 131 I-F(ab') 2 was much superior in quality to that with intact 131 I-A7 MoAb. The use of F(ab') 2 fragments may be effective for tumor diagnosis and therapy. (author)

  7. Distribution and pharmacokinetic analysis of angiostatin radioiodine labeled with high stability

    International Nuclear Information System (INIS)

    Song, Sung Hee; Jung, Kyung-Ho; Paik, Jin-Young; Koh, Bong-Ho; Bae, Joon-Sang; Choe, Yearn Seong; Lee, Kyung-Han; Kim, Byung-Tae

    2005-01-01

    Objective: Radiotracers of anticancer agents provide important information on its in vivo handling. Angiostatin (AST) is a promising anticancer drug with potent antiangiogenic effects, but reported AST radiotracers suffer from poor in vivo stability. In this study, we synthesized an AST probe radioiodinated via the Bolton-Hunter reagent ( 125 I-BH-AST) and investigated its stability and biokinetics in mice. Methods: 125 I-BH-AST and conventional direct radioiodinated 125 I-AST were evaluated for human endothelial cell binding characteristics. In vivo stability of the radiotracers was compared by biodistribution studies in normal ICR mice. Angiostatin pharmacokinetics was analyzed by serial blood sampling after intravenous injection of 125 I-BH-AST with varying AST concentrations in mice. Results: Both 125 I-AST and 125 I-BH-AST retained selective endothelial binding as demonstrated by dose-dependent inhibition by nonradiolabeled AST. 125 I-BH-AST was substantially more stable in mice than 125 I-AST, with 28- and 7-fold lower 24-h thyroid and blood activities, respectively (15.5±1.5 vs. 430.9±32.2 and 0.1±0.0 vs. 0.8±0.0 %ID/g; both P 125 I-BH-AST, we found that 24-h AST accumulation was highest in the kidneys, followed by the liver and lungs. Kinetic analysis of 125 I-BH-AST revealed AST to have linear pharmacokinetics with a T 1/2 of 5.8±2.6 h, volume of distribution (V d ) of 6.8±1.3 ml and clearance of 0.8±0.1 ml/h. Conclusion: Radioiodine-labeled AST prepared by the BH method provides a radioprobe with superior stability and improved in vivo biokinetics that is useful for distribution and pharmacokinetic studies

  8. In vivo toxicity studies of europium hydroxide nanorods in mice

    International Nuclear Information System (INIS)

    Patra, Chitta Ranjan; Abdel Moneim, Soha S.; Wang, Enfeng; Dutta, Shamit; Patra, Sujata; Eshed, Michal; Mukherjee, Priyabrata; Gedanken, Aharon; Shah, Vijay H.; Mukhopadhyay, Debabrata

    2009-01-01

    Lanthanide nanoparticles and nanorods have been widely used for diagnostic and therapeutic applications in biomedical nanotechnology due to their fluorescence and pro-angiogenic properties to endothelial cells, respectively. Recently, we have demonstrated that europium (III) hydroxide [Eu III (OH) 3 ] nanorods, synthesized by the microwave technique and characterized by several physico-chemical techniques, can be used as pro-angiogenic agents which introduce future therapeutic treatment strategies for severe ischemic heart/limb disease, and peripheral ischemic disease. The toxicity of these inorganic nanorods to endothelial cells was supported by several in vitro assays. To determine the in vivo toxicity, these nanorods were administered to mice through intraperitoneal injection (IP) everyday over a period of seven days in a dose dependent (1.25 to 125 mg kg -1 day -1 ) and time dependent manner (8-60 days). Bio-distribution of europium elements in different organs was analyzed by inductively coupled plasma mass spectrometry (ICPMS). Short-term (S-T) and long-term (L-T) toxicity studies (mice euthanized on days 8 and 60 for S-T and L-T, respectively) show normal blood hematology and serum clinical chemistry with the exception of a slight elevation of liver enzymes. Histological examination of nanorod-treated vital organs (liver, kidney, spleen and lungs) showed no or only mild histological changes that indicate mild toxicity at the higher dose of nanorods.

  9. The study of hormesis effection on mice by Zuibyougan

    International Nuclear Information System (INIS)

    Ishii, Takeshi; Nishina, Kazunari.

    1997-01-01

    Although various biohazards of high-dose radiation have been known, Dr. Lucky (1980) paid an attention to low-dose radiation and reported that a low-dose exposure which allows normal functioning of cellular repairing mechanism caused some favorable effects such as growth stimulation, elongation of life-span etc. And these effects were named as Hormesis effects by him. In this study, the biological effects of Zuibyougan, a ionizing radioactive rock produced from a mine were investigated on the growth and locomotor activities in TRC mice. Drinking water containing Zuibyougan in 3 different forms (chip, sand and fine powder) at a concentration of 25 g/100 ml was administered from the time of weaning and tap water was given to the control group. Their body weights were measured once a week up to 12 weeks of age. Body weight of the group administered with either type of Zuibyougan was slightly higher than that of the control. The increasing effects were most marked for the group given in powder form. However, the effects were not statistically significant. Further, the locomotive activities determined by round running method were also slightly higher in the mice administered with Zuibyougan. (M.N.)

  10. Effect of Garlic, Gingko, and St. John's Wort Extracts on the Pharmacokinetics of Fexofenadine: A Mechanistic Study.

    Science.gov (United States)

    Turkanovic, Jasmina; Ward, Michael B; Gerber, Jacobus P; Milne, Robert W

    2017-05-01

    The aim of this study was to determine the effects of garlic and ginkgo herbal extracts on the pharmacokinetics of the P-glycoprotein (P-gp)/organic anion-transporting polypeptides (Oatps) substrate fexofenadine. Male rats were dosed orally with garlic (120 mg/kg), ginkgo (17 mg/kg), St. John's wort (SJW; 1000 mg/kg; positive control), or Milli-Q water for 14 days. On day 15, rats either were administered fexofenadine (orally or i.v.), had their livers isolated and perfused with fexofenadine, or had their small intestines divided into four segments (SI-SIV) and analyzed for P-gp and Oatp1a5. In vivo, SJW increased the clearance of i.v. administered fexofenadine by 28%. Garlic increased the area under the curve 0-∞ and maximum plasma concentration of orally administered fexofenadine by 47% and 85%, respectively. Ginkgo and SJW had no effect on the oral absorption of fexofenadine. In the perfused liver, garlic, ginkgo, and SJW increased the biliary clearance of fexofenadine with respect to perfusate by 71%, 121%, and 234%, respectively. SJW increased the biliary clearance relative to the liver concentration by 64%. The ratio of liver to perfusate concentrations significantly increased in all treated groups. The expression of Oatp1a5 in SI was increased by garlic (88%) and SJW (63%). There were no significant changes in the expression of P-gp. Induction of intestinal Oatp1a5 by garlic may explain the increased absorption of orally administered fexofenadine. Ginkgo had no effect on the expression of intestinal P-gp or Oatp1a5. A dual inductive effect by SJW on opposing intestinal epithelial transport by Oatp1a5 and P-gp remains a possibility. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  11. Automated chemoenzymatic synthesis of no-carrier-added [carbonyl-11C]propionyl L-carnitine for pharmacokinetic studies

    International Nuclear Information System (INIS)

    Davenport, R.J.; Pike, V.W.; Dowsett, K.; Turton, D.R.; Poole, K.

    1997-01-01

    Propionyl-L-carnitine (PLC) is under development as a therapeutic for the treatment of peripheral artery disease, coronary heart disease and chronic heart failure. Three methods were examined for labelling PLC in its propionyl group with positron-emitting carbon-11 (t 1/2 = 20.3 min), one chemical and two chemoenzymatic. The former was based on the preparation of [ 11 C]propionyl chloride as labelling agent via 11 C-carboxylation of ethylmagnesium bromide with cyclotron-produced [ 11 C]carbon dioxide and subsequent chlorination. Reaction of carrier-added [ 11 C]propionyl chloride with L-carnitine in trifluoroacetic acid gave [ 11 C]PLC in 12% radiochemical yield (decay-corrected) from cyclotron-produced [ 11 C]carbon dioxide. However, the radiosynthesis was unsuccessful at the no-carrier added (NCA) level of specific radioactivity. [ 11 C]Propionate, as a radioactive precursor for chemoenzymatic routes, was prepared via carboxylation of ethylmagnesium bromide with [ 11 C]carbon dioxide and hydrolysis. NCA [ 11 C]PLC was prepared in 68 min in 14% radiochemical yield (decay-corrected) from [ 11 C]propionate via sequential conversions catalysed by acetate kinase, phosphotransacetylase and carnitine acetyltransferase. A superior chemoenzymatic synthesis of NCA [ 11 C]PLC was developed, based on the use of a novel supported Grignard reagent for the synthesis of [ 11 C]propionate and conversions by S-acetyl-CoA synthetase and carnitine acetyltransferase. This gave an overall radiochemical yield of 30-48% (decay-corrected). This synthesis was automated for radiation safety and provides pure NCA [ 11 C]PLC in high radioactivities ready for intravenous administration within 25 min from radionuclide production. The [ 11 C]PLC is suitable for pharmacokinetic studies in human subjects with PET and the elucidation of the fate of the propionyl group of PLC in vivo. (Author)

  12. Studies on separation and pharmacokinetics of m-nisoldipine enantiomers in beagle dog plasma by LC/MS/MS.

    Science.gov (United States)

    Li, Min; Yuan, Lin; Li, Xiuqing; Zhi, Xuran; Sheng, Ning; Zhang, Lantong

    2013-11-01

    A rapid, sensitive and selective liquid chromatography-tandem mass spectrometric (LC/MS/MS) method was developed and validated for the separation and determination of m-nisoldipine enantiomers in beagle dog plasma. Samples were pretreated by a single-step protein precipitation with acetonitrile. After m-nisoldipine racemic administration to beagle dogs, samples of m-nisoldipine enantiomers in beagle dog plasma were separated and determined on a ULTRON ES-OVM column (150 × 4.6 mm, 5 μm) at 20°C with a mobile phase consisted of methanol-acetonitrile-ammonium acetate (pH 7.0; 2mM) (15:15:70, v/v/v) at a flow rate of 0.8 mL/min. Chromatograms were monitored at 237 nm, and the API 4000 triple quadrupole mass spectrometer was operated in multiple reaction monitoring (MRM) scan mode using ElectroSpray ionization (ESI) source. The good linearity (rs=0.9958 and rr=0.9983) were found in the range 0.25-20 ng/mL. The lower limit of quantification (LLOQ) obtained was 0.25 ng/mL (n=6). All the validation data, such as accuracy, precision, intra-day and inter-day repeatability, were within the required limits. The method was successfully applied to separation and pharmacokinetics of m-nisoldipine enantiomers in beagle dog plasma. The result of statistics analysis shows that there are no significant differences between R-(-)-m-nisoldipine and S-(+)-m-nisoldipine (p>0.05). The study provides necessary evidences for the research and new drug development of m-nisoldipine enantiomers. Copyright © 2013. Published by Elsevier B.V.

  13. Phase I and pharmacokinetic study of combined treatment with perifosine and radiation in patients with advanced solid tumours

    International Nuclear Information System (INIS)

    Vink, Stefan R.; Schellens, Jan H.M.; Beijnen, Jos H.; Sindermann, Herbert; Engel, Juergen; Dubbelman, Ria; Moppi, Gemi; Hillebrand, Michel J.X.; Bartelink, Harry; Verheij, Marcel

    2006-01-01

    Purpose: Perifosine is an orally applicable, membrane-targeted alkylphosphocholine analogue with antitumour activity and radiosensitising properties in preclinical models. The purpose of this phase I study was to determine the feasibility and tolerability of concurrent daily perifosine and radiation in patients with advanced cancer. Patients and methods: Starting dose of perifosine was 50 mg/day; dose escalation was in steps of 50 mg. Daily administration commenced 2 days before radiotherapy and was continued throughout the radiation treatment. At least three patients were entered at each dose level; at the 150 mg/day level 10 patients were included. Pharmacokinetic sampling was performed weekly pre-dosing. Twenty-one patients were entered. Tumour types included NSCLC (n = 17), prostate, oesophageal, colon and bladder cancer. Most patients (16/21) had received prior chemotherapy; none radiotherapy. Median number of daily perifosine administrations was 31 (range 24-53). Mean radiation dose (BED 1 ) was 59.8 Gy (range 50.7-87.5 Gy in 13-28 fractions). Results: Major drug-related toxicities according to CTC criteria were nausea in 57%, fatigue in 48%, vomiting in 38%, diarrhoea in 38% and anorexia in 19%. No bone marrow toxicity was observed. DLT (nausea/vomiting) was encountered in two of five patients at the 200 mg/day dose level. Dose-dependent steady-state plasma levels were reached after 1 week. Major radiotherapy-related acute toxicity consisted of dysphagia in 38% and pneumonitis in 29%. Conclusion: Perifosine can be safely combined with fractionated radiotherapy. A dosage of 150 mg/day, to be started at least 1 week prior to radiotherapy, is recommended for phase II evaluation

  14. Physiologically based pharmacokinetic toolkit to evaluate environmental exposures: Applications of the dioxin model to study real life exposures

    Energy Technology Data Exchange (ETDEWEB)

    Emond, Claude, E-mail: claude.emond@biosmc.com [BioSimulation Consulting Inc, Newark, DE (United States); Ruiz, Patricia; Mumtaz, Moiz [Division of Toxicology and Human Health Sciences, Agency for Toxic Substances and Disease Registry, Atlanta, GA (United States)

    2017-01-15

    Chlorinated dibenzo-p-dioxins (CDDs) are a series of mono- to octa-chlorinated homologous chemicals commonly referred to as polychlorinated dioxins. One of the most potent, well-known, and persistent member of this family is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). As part of translational research to make computerized models accessible to health risk assessors, we present a Berkeley Madonna recoded version of the human physiologically based pharmacokinetic (PBPK) model used by the U.S. Environmental Protection Agency (EPA) in the recent dioxin assessment. This model incorporates CYP1A2 induction, which is an important metabolic vector that drives dioxin distribution in the human body, and it uses a variable elimination half-life that is body burden dependent. To evaluate the model accuracy, the recoded model predictions were compared with those of the original published model. The simulations performed with the recoded model matched well with those of the original model. The recoded model was then applied to available data sets of real life exposure studies. The recoded model can describe acute and chronic exposures and can be useful for interpreting human biomonitoring data as part of an overall dioxin and/or dioxin-like compounds risk assessment. - Highlights: • The best available dioxin PBPK model for interpreting human biomonitoring data is presented. • The original PBPK model was recoded from acslX to the Berkeley Madonna (BM) platform. • Comparisons were made of the accuracy of the recoded model with the original model. • The model is a useful addition to the ATSDR's BM based PBPK toolkit that supports risk assessors. • The application of the model to real-life exposure data sets is illustrated.

  15. Differential effects of liver steatosis on pharmacokinetic profile of two closely related hepatoselective NO-donors; V-PYRRO/NO and V-PROLI/NO.

    Science.gov (United States)

    Kus, Kamil; Kus, Edyta; Zakrzewska, Agnieszka; Jawien, Wojciech; Sitek, Barbara; Walczak, Maria; Chlopicki, Stefan

    2017-06-01

    To analyze the effect of liver steatosis and obesity on pharmacokinetic profile of two structurally-related liver-selective NO-donors - V-PYRRO/NO and V-PROLI/NO. C57BL/6 mice were fed control or high-fat diet for 15 weeks to induced liver steatosis and obesity (HFD mice). Pharmacokinetics and renal elimination studies were conducted in vivo following iv dosing of V-PYRRO/NO and V-PROLI/NO (0.03mmol/kg). Hepatic clearance was evaluated ex vivo in the isolated perfused mice liver and in vitro with the use of liver microsomes. V-PYRRO/NO and V-PROLI/NO, despite similar structure, displayed different pharmacokinetic properties. V-PYRRO/NO was uptaken and metabolized by the liver, while V-PROLI/NO was eliminated unchanged with urine. In HFD mice, despite increased CYP450 metabolism of V-PYRRO/NO the elimination rate was slower most likely due to the impairment of hepatic microcirculation caused by liver fat accumulation. In turn, in HFD mice renal clearence of V-PROLI/NO was accelerated and volume of distribution was increased most likely due to additional intracellular water in HFD mice. The pharmacokinetics of V-PROLI/NO, the novel proline-based analog of V-PYRRO/NO with additional single carboxylic acid moiety, attached to the molecule of V-PYRRO/NO to improve the water solubility, was differently affected by liver steatosis and obesity as compared with the parent compound V-PYRRO/NO. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  16. GC-MS and GC-MS/MS measurement of ibuprofen in 10-μL aliquots of human plasma and mice serum using [α-methylo-2H3]ibuprofen after ethyl acetate extraction and pentafluorobenzyl bromide derivatization: Discovery of a collision energy-dependent H/D isotope effect and pharmacokinetic application to inhaled ibuprofen-arginine in mice.

    Science.gov (United States)

    Tsikas, Dimitrios; Kayacelebi, Arslan Arinc; Hanff, Erik; Mitschke, Anja; Beckmann, Bibiana; Tillmann, Hanns-Christian; Gutzki, Frank-Mathias; Müller, Meike; Bernasconi, Corrado

    2017-02-01

    -ibuprofen and d 0 -ibuprofen did not change upon incubation at 37°C up to 60min. The trough pharmacokinetics of an inhaled arginine-containing ibuprofen preparation in mice was studied after once-daily treatment (0.0, 0.07, 0.4 and 2.5mg/kg body weight) for three days. A linear relationship between ibuprofen concentration in serum (10μL) and administered dose 24h after the last drug administration was observed. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Pharmacokinetic interaction study of sulphasalazine in healthy subjects and the impact of curcumin as an in vivo inhibitor of BCRP

    Science.gov (United States)

    Kusuhara, Hiroyuki; Furuie, Hidetoshi; Inano, Akihiro; Sunagawa, Akihiro; Yamada, Saiko; Wu, Chunyong; Fukizawa, Shinya; Morimoto, Nozomi; Ieiri, Ichiro; Morishita, Mariko; Sumita, Kiminobu; Mayahara, Hiroshi; Fujita, Takuya; Maeda, Kazuya; Sugiyama, Yuichi

    2012-01-01

    BACKGROUND AND PURPOSE An ATP-binding cassette (ABC) transporter, breast cancer resistance protein (BCRP)/ABCG2, limits oral bioavailability of sulphasalazine. Here we examined the effect of curcumin, the principal curcuminoid of turmeric, on oral bioavailability of microdoses and therapeutic doses of sulphasalazine in humans. EXPERIMENTAL APPROACH Effects of curcumin were measured on the ATP-dependent sulphasalazine uptake by hBCRP-expressing membrane vesicles and on oral bioavailability of sulphasalazine in wild-type and Bcrp(–/–) mice. Eight healthy Japanese subjects received an oral dose of sulphasalazine suspension (100 µg) or tablets (2 g) alone or after curcumin tablets (2 g). Uptake of sulphasalazine was studied in HEK293 cells transfected with the influx transporter (OATP)2B1. KEY RESULTS Curcumin was a potent hBCRP inhibitor in vitro (Ki 0.70 ± 0.41 µM). Curcumin increased the area under the curve (AUC)0–8 of plasma sulphasalazine eightfold in wild-type mice at 300 and 400 mg·kg−1, but not in Bcrp(–/–) mice. Curcumin increased AUC0–24 of plasma sulphasalazine 2.0-fold at microdoses and 3.2-fold at therapeutic doses in humans. Non-linearity of the dose–exposure relationship was observed between microdoses and therapeutic doses of sulphasalazine. Sulphasalazine was a substrate for OATP2B1 (Km 1.7 ± 0.3 µM). Its linear index (dose/Km) at the therapeutic dose was high and may saturate OATP2B1. CONCLUSIONS AND IMPLICATIONS Curcumin can be used to investigate effects of BCRP on oral bioavailability of drugs in humans. Besides the limited dissolution, OATP2B1 saturation is a possible mechanism underlying non-linearity in the dose–exposure relationship of sulphasalazine. PMID:22300367

  18. Comparison of pharmacokinetic profiles of brand-name and generic formulations of citalopram and venlafaxine: a crossover study.

    Science.gov (United States)

    Chenu, Franck; Batten, Lisa A; Zernig, Gerald; Ladstaetter, Elisabeth; Hébert, Chantal; Blier, Pierre

    2009-07-01

    Generic drugs are lower-cost versions of patent-expired brand-name medications. Bioequivalence is decreed when the 90% confidence intervals for the ratios of the generic to the reference compound for the area under the curve and maximum plasma concentration (C(max)) fall within a 0.80 to 1.25 range. The aim of the present pilot study was to compare the pharmacokinetic profiles of brand-name and generic formulations of citalopram and extended-release venlafaxine. Effexor XR/Novo-venlafaxine XR 75 mg and Celexa/Gen-citalopram 40 mg were studied in a randomized crossover design. Healthy male volunteers took either Effexor XR or Novo-venlafaxine XR for 4 days, a 4-day washout was allowed, and then participants took the other venlafaxine formulation for 4 days. This was followed by a washout of at least 7 days. The participants then took Celexa or Gen-citalopram for 8 days, a 14-day washout was allowed, and then participants took the other citalopram formulation for 8 days. In each of the study phases, the sequence of treatment (brand-name x generic) was randomly assigned. Plasma levels of drugs were measured at fixed intervals after participants took the drugs and at steady state. The study was conducted from November 2007 through July 2008. Twelve participants completed the venlafaxine study. Nine of the participants, plus 3 new participants, were then enrolled in the citalopram study, to maintain a total of 12. The plasma levels of citalopram were similar after ingestion of the brand-name and generic drugs. After ingestion of venlafaxine, the C(max) values were 36 +/- 6 ng/mL and 52 +/- 8 ng/mL in the brand-name and generic groups, respectively. The ratio of the log-transformed values of C(max) was 150% and, therefore, not within the acceptable 80% to 125% range. The concentration of the active metabolite of venlafaxine (O-desmethyl-venlafaxine [ODV]) was also significantly increased in the generic group (+43% higher in the generic group at 3 h; +48% higher at 5 h; p

  19. Time to reach tacrolimus maximum blood concentration,mean residence time, and acute renal allograft rejection: an open-label, prospective, pharmacokinetic study in adult recipients.

    Science.gov (United States)

    Kuypers, Dirk R J; Vanrenterghem, Yves

    2004-11-01

    The aims of this study were to determine whether disposition-related pharmacokinetic parameters such as T(max) and mean residence time (MRT) could be used as predictors of clinical efficacy of tacrolimus in renal transplant recipients, and to what extent these parameters would be influenced by clinical variables. We previously demonstrated, in a prospective pharmacokinetic study in de novo renal allograft recipients, that patients who experienced early acute rejection did not differ from patients free from rejection in terms of tacrolimus pharmacokinetic exposure parameters (dose interval AUC, preadministration trough blood concentration, C(max), dose). However, recipients with acute rejection reached mean (SD) tacrolimus T(max) significantly faster than those who were free from rejection (0.96 [0.56] hour vs 1.77 [1.06] hours; P clearance nor T(1/2) could explain this unusual finding, we used data from the previous study to calculate MRT from the concentration-time curves. As part of the previous study, 100 patients (59 male, 41 female; mean [SD] age, 51.4 [13.8] years;age range, 20-75 years) were enrolled in the study The calculated MRT was significantly shorter in recipients with acute allograft rejection (11.32 [031] hours vs 11.52 [028] hours; P = 0.02), just like T(max) was an independent risk factor for acute rejection in a multivariate logistic regression model (odds ratio, 0.092 [95% CI, 0.014-0.629]; P = 0.01). Analyzing the impact of demographic, transplantation-related, and biochemical variables on MRT, we found that increasing serum albumin and hematocrit concentrations were associated with a prolonged MRT (P calculated MRT were associated with a higher incidence of early acute graft rejection. These findings suggest that a shorter transit time of tacrolimus in certain tissue compartments, rather than failure to obtain a maximum absolute tacrolimus blood concentration, might lead to inadequate immunosuppression early after transplantation.

  20. ASAP ECMO: Antibiotic, Sedative and Analgesic Pharmacokinetics during Extracorporeal Membrane Oxygenation: a multi-centre study to optimise drug therapy during ECMO

    Directory of Open Access Journals (Sweden)

    Shekar Kiran

    2012-11-01

    Full Text Available Abstract Background Given the expanding scope of extracorporeal membrane oxygenation (ECMO and its variable impact on drug pharmacokinetics as observed in neonatal studies, it is imperative that the effects of the device on the drugs commonly prescribed in the intensive care unit (ICU are further investigated. Currently, there are no data to confirm the appropriateness of standard drug dosing in adult patients on ECMO. Ineffective drug regimens in these critically ill patients can seriously worsen patient outcomes. This study was designed to describe the pharmacokinetics of the commonly used antibiotic, analgesic and sedative drugs in adult patients receiving ECMO. Methods/Design This is a multi-centre, open-label, descriptive pharmacokinetic (PK study. Eligible patients will be adults treated with ECMO for severe cardiac and/or respiratory failure at five Intensive Care Units in Australia and New Zealand. Patients will receive the study drugs as part of their routine management. Blood samples will be taken from indwelling catheters to investigate plasma concentrations of several antibiotics (ceftriaxone, meropenem, vancomycin, ciprofloxacin, gentamicin, piperacillin-tazobactum, ticarcillin-clavulunate, linezolid, fluconazole, voriconazole, caspofungin, oseltamivir, sedatives and analgesics (midazolam, morphine, fentanyl, propofol, dexmedetomidine, thiopentone. The PK of each drug will be characterised to determine the variability of PK in these patients and to develop dosing guidelines for prescription during ECMO. Discussion The evidence-based dosing algorithms generated from this analysis can be evaluated in later clinical studies. This knowledge is vitally important for optimising pharmacotherapy in these most severely ill patients to maximise the opportunity for therapeutic success and minimise the risk of therapeutic failure. Trial registration ACTRN12612000559819

  1. Positron emission tomography (PET) study of the alterations in brain pharmacokinetics of methamphetamine in methamphetamine sensitized animals

    International Nuclear Information System (INIS)

    Nakamura, Hitoshi

    2001-01-01

    I investigated the differences in brain pharmacokinetics of [ 11 C]methamphetamine ([ 11 C]MAP) in normal and MAP sensitized animals using positron emission tomography (PET). [ 11 C]MAP was synthesized by an automated on-line [ 11 C]methylation system. I newly produced MAP sensitized dog and monkey by repeated MAP treatment. The maximal level of accumulation of [ 11 C]MAP in the sensitized dog brain was 1.4 times higher than that in the control. This result suggests the changes in the pharmacokinetic profile of MAP in the brain affect the development or expression of MAP-induced behavioral sensitization. However, the overaccumulation of [ 11 C]MAP in the sensitized monkey brain was not observed due to the influence of anesthesia. (author)

  2. Positron emission tomography (PET) study of the alterations in brain pharmacokinetics of methamphetamine in methamphetamine sensitized animals

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, Hitoshi [Tohoku Univ., Sendai (Japan). Hospital

    2001-08-01

    I investigated the differences in brain pharmacokinetics of [{sup 11}C]methamphetamine ([{sup 11}C]MAP) in normal and MAP sensitized animals using positron emission tomography (PET). [{sup 11}C]MAP was synthesized by an automated on-line [{sup 11}C]methylation system. I newly produced MAP sensitized dog and monkey by repeated MAP treatment. The maximal level of accumulation of [{sup 11}C]MAP in the sensitized dog brain was 1.4 times higher than that in the control. This result suggests the changes in the pharmacokinetic profile of MAP in the brain affect the development or expression of MAP-induced behavioral sensitization. However, the overaccumulation of [{sup 11}C]MAP in the sensitized monkey brain was not observed due to the influence of anesthesia. (author)

  3. Biophysical study of mice blood after whole body irradiation

    Science.gov (United States)

    Saad El Din, Alsha A.; Desouky, Omar S.; El Behay, Amin Z.; El Sayed, Anwar A.

    1996-05-01

    The immediate of whole body fractionated doses of 137Cs gamma rays totalling 13 Gy on mice as well as the late effects of accumulative dose of 10 Gy (8 days after exposure) were studied. Changes due to gamma irradiation in hemoglobin conductivity and buffer capacity indicate the appearance of hydrophobic groups and changes in hydrophilic/hydrophobic ratio. These changes demonstrate different degrees of unfolding and refolding of the hemoglobin molecule. The viscosity coefficient of hemoglobin is found to increase at fractionated doses of 7 and 13 Gy. Such effect seems to be due to aggregation of the protein part of hemoglobin. The fractionated dose of 13 Gy causes changes in the electronic state of oxyhemoglobin indicated by an increase in methemoglobin which reduces biological activity.

  4. Study of pharmacokinetics and biodistribution of radiolabelled receptor specific peptides in laboratory animals

    International Nuclear Information System (INIS)

    Laznickova, A.; Laznicek, M.; Trejtnar, F.; Maecke, H.R.; Mather, S.J.

    2001-01-01

    Somatostatin analogues labelled with different radionuclides could be employed for visualization or treatment of somatostatin receptor-positive tumours. An octapeptide 111 In [DTPA] octreotide is a synthetic radiolabelled somatostatin analogue which is currently in clinical use for detecting small neuroendocrine tumours and metastases not detectable by conventional means. However, several other somatostatin analogues have been under development and testing. The aim of this study was to radiolabel selected somatostatin receptor-binding octapeptides by different radionuclides and to report the results of their biodistribution in rats. The study was focused on the direct labelling of vapreotide (RC-160) with 99m Tc, on the conjugates of octreotide with DFO (desferrioxamine) for labelling with 67 Ga, and on the conjugates of octreotide and TOC with DOTA (tetraazacyclo-dodecane tetraacetic acid) for labelling with 88 Y. In the present study, 88 Y isotope instead of 90 Y was used as a label as 88 Y exhibits a longer half life of decay and emits gamma radiation which can be much more easily detected in biological samples than beta emission. The labelling of octreotide analogues with metal radionuclides using derived bifunctional chelates was simple, straightforward and consistently resulted in high radiochemical purity of the product. On the other hand, the application of the direct labelling method for labelling of RC-160 with 99m Tc was difficult because all procedures had to be made under nitrogen atmosphere and an attainment of high yield proved to be highly dependent on the accurate observation of reaction conditions. The labelling efficiency makes an immediate use of the radiolabelled RC-160 for biological studies impossible and it is necessary to involve the purification step into the labelling procedure. All radiolabelled receptor specific peptides under study exhibited rapid radioactivity clearance from the blood and most organs and tissues. On the other hand

  5. Integrated identification, qualification and quantification strategy for pharmacokinetic profile study of Guizhi Fuling capsule in healthy volunteers

    OpenAIRE

    Yun-Xi Zhong; Xiao-Liang Jin; Shi-Yin Gu; Ying Peng; Ke-Rong Zhang; Bing-Chen Ou-Yang; Yu Wang; Wei Xiao; Zhen-Zhong Wang; Ji-Ye Aa; Guang-Ji Wang; Jian-Guo Sun

    2016-01-01

    Guizhi Fuling capsule (GZFL), a traditional Chinese medicine formulation, is widely used in China to relieve pain from dysmenorrhea and is now in a Phase II clinical trial in the USA. Due to the low exposure of the five main medicative ingredients (amygdalin, cinnamic acid, gallic acid, paeoniflorin and paeonol) of GZFL in human, a strategy was built to qualitatively and quantitatively identify the possible metabolites of GZFL and to describe the pharmacokinetic profiles of GZFL in human. In ...

  6. Pilot study of the pharmacokinetics of betel nut and betel quid biomarkers in saliva, urine, and hair of betel consumers

    OpenAIRE

    Franke, Adrian A.; Li, Xingnan; Lai, Jennifer F.

    2015-01-01

    Approximately 600 million people worldwide practise the carcinogenic habit of betel nut/quid chewing. Carcinogenic N-nitroso compounds have been identified in saliva or urine of betel chewers and the betel alkaloid arecoline in hair from habitual betel quid chewers. However, the pharmacokinetic parameters of these compounds have been little explored. Assessment of betel use by biomarkers is urgently needed to evaluate the effectiveness of cessation programmes aimed at reducing betel consumpti...

  7. Cambridge glioma trial of misonidazole and radiation therapy with associated pharmacokinetic studies

    International Nuclear Information System (INIS)

    Bleehen, N.M.

    1980-01-01

    Fifty-five patients with grade 3 and 4 supratentorial astrocytomas, were randomized into a three-limb study. At 9 months after the last treatment there were no differences in survival between the treatment groups. No cases of peripheral neuropathy were seen. Investigations into the possible cause of this are presented. It is thought that microsomal enzyme induction by the anticonvulsants phenobarbitone and phenytoin resulted in increased 0-demethylation of the misonidazole. Clinical data to confirm this view are presented. Current MRC protocols of misonidazole studies on gliomas and carcinomas of the cervix and head and neck are summarized

  8. Pharmacokinetics and bioavailability study of two ondansetron oral soluble film formulations in fasting healthy male Chinese volunteers

    Directory of Open Access Journals (Sweden)

    Zhu YB

    2015-08-01

    Full Text Available Yubing Zhu,1 Qian Zhang,1 Jianjun Zou,2 Meng Wan,1 Zheng Zhao,1 Junrong Zhu1 1Department of Pharmacy, 2Laboratory of Clinical Pharmacology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu, People’s Republic of China Background: Ondansetron oral soluble film is designed to be applied on top of the tongue without requiring water to aid dissolution or swallowing, which is especially fitting for nausea and vomiting patients.Purpose: This study was conducted to compare the bioavailability of two 8 mg ondansetron oral soluble film formulations.Patients and methods: This randomized, open-label, two-period crossover study was performed under fasting conditions. A total of ten eligible subjects were randomly assigned at a 1:1 ratio to receive a single 8 mg dose of the test and reference ondansetron oral soluble film formulations, followed by a 1-week washout period and administration of the alternate formulation. The concentrations of ondansetron were assayed using an liquid chromatograph-mass spectrometer/mass spectrometer (LC-MS/MS method. For analysis of pharmacokinetic properties, including the peak concentration of Tmax (Cmax, AUC from time 0 (baseline to t hours (AUC0–t, and AUC from baseline to infinity (AUC0–∞, blood samples were obtained at intervals over the 24-hour period after studying drug administration. Tolerability was assessed by monitoring vital signs and laboratory tests (hematology, blood biochemistry, hepatic function, and urinalysis and by questioning subjects about adverse events.Results: The mean (standard derivation [SD] relative bioavailability was 96.5 (23.7%. The 90% confidence intervals (CIs for the log-transformed ratios of Cmax and AUC0–t were 84.71%–103.28% and 91.38%–108.60%, respectively (P>0.05. Similar results were found for the data without log-transformation. No statistically significant differences were found based on analysis of variance. No significant adverse events occurred

  9. Pharmacokinetics and bioavailability of plant lignan 7-hydroxymatairesinol and effects on serum enterolactone and clinical symptoms in postmenopausal women: a single-blinded, parallel, dose-comparison study.

    Science.gov (United States)

    Udani, Jay K; Brown, Donald J; Tan, Maria Olivia C; Hardy, Mary

    2013-01-01

    7-Hydroxymaitairesinol (7-HMR) is a naturally occurring plant lignan found in whole grains and the Norway spruce (Piciea abies). The purpose of this study was to evaluate the bioavailability of a proprietary 7-HMR product (HMRlignan, Linnea SA, Locarno, Switzerland) through measurement of lignan metabolites and metabolic precursors. A single-blind, parallel, pharmacokinetic and dose-comparison study was conducted on 22 postmenopausal females not receiving hormone replacement therapy. Subjects were enrolled in either a 36 mg/d (low-dose) or 72 mg/d dose (high-dose) regimen for 8 weeks. Primary measured outcomes included plasma levels of 7-HMR and enterolactone (ENL), and single-dose pharmacokinetic analysis was performed on a subset of subjects in the low-dose group. Safety data and adverse event reports were collected as well as data on hot flash frequency and severity. Pharmacokinetic studies demonstrated 7-HMR C max = 757.08 ng/ml at 1 hour and ENL C max = 4.8 ng/ml at 24 hours. From baseline to week 8, plasma 7-HMR levels increased by 191% in the low-dose group (p < 0.01) and by 1238% in the high-dose group (p < 0.05). Plasma ENL levels consistently increased as much as 157% from baseline in the low-dose group and 137% in the high-dose group. Additionally, the mean number of weekly hot flashes decreased by 50%, from 28.0/week to 14.3/week (p < 0.05) in the high-dose group. No significant safety issues were identified in this study. The results demonstrate that HMRlignan is quickly absorbed into the plasma and is metabolized to ENL in healthy postmenopausal women. Clinically, the data demonstrate a statistically significant improvement in hot flash frequency. Doses up to 72 mg/d HMRlignan for 8 weeks were safe and well tolerated in this population.

  10. Dose study of the multikinase inhibitor, LY2457546, in patients with relapsed acute myeloid leukemia to assess safety, pharmacokinetics, and pharmacodynamics

    International Nuclear Information System (INIS)

    Wacheck, Volker; Lahn, Michael; Dickinson, Gemma; Füreder, Wolfgang; Meyer, Renata; Herndlhofer, Susanne; Füreder, Thorsten; Dorfner, Georg; Pillay, Sada; André, Valérie; Burkholder, Timothy P; Akunda, Jacqueline K; Flye-Blakemore, Leann; Van Bockstaele, Dirk; Schlenk, Richard F; Sperr, Wolfgang R; Valent, Peter

    2011-01-01

    Acute myeloid leukemia (AML) is a life-threatening malignancy with limited treatment options in chemotherapy-refractory patients. A first-in-human dose study was designed to investigate a safe and biologically effective dose range for LY2457546, a novel multikinase inhibitor, in patients with relapsed AML. In this nonrandomized, open-label, dose escalation Phase I study, LY2457546 was administered orally once a day. Safety, pharmacokinetics, changes in phosphorylation of target kinases in AML blasts, and risk of drug–drug interactions (DDI) were assessed. Five patients were treated at the starting and predicted minimal biologically effective dose of 50 mg/day. The most commonly observed adverse events were febrile neutropenia, epistaxis, petechiae, and headache. The majority of adverse events (81%) were Grade 1 or 2. One patient had generalized muscle weakness (Grade 3), which was deemed to be a dose-limiting toxicity. Notably, the pharmacokinetic profile of LY2457546 showed virtually no elimination of LY2457546 within 24 hours, and thus prevented further dose escalation. No significant DDI were observed. Ex vivo flow cytometry studies showed downregulation of the phosphoproteins, pcKIT, pFLT3, and pS6, in AML blasts after LY2457546 administration. No medically relevant responses were observed in the five treated patients. No biologically effective dose could be established for LY2457546 in chemotherapy-resistant AML patients. Lack of drug clearance prevented safe dose escalation, and the study was terminated early. Future efforts should be made to develop derivatives with a more favorable pharmacokinetic profile

  11. Contribution of stable isotopes to the study of pharmacokinetics of magnesium salts

    International Nuclear Information System (INIS)

    Benech, H.

    1999-01-01

    The use of stable isotopes as labels is becoming an attractive tool for the study of magnesium behavior in humans. It has been used two stable isotopes of magnesium, 25 Mg and 26 Mg, to measure the absolute bioavailability of a pharmaceutical form of magnesium. (N.C.)

  12. A PHASE-II AND PHARMACOKINETIC STUDY WITH ORAL PIRITREXIM FOR METASTATIC BREAST-CANCER

    NARCIS (Netherlands)

    DEVRIES, EGE; GIETEMA, JA; WORKMAN, P; SCOTT, JE; CRAWSHAW, A; DOBBS, HJ; DENNIS, [No Value; MULDER, NH; SLEIJFER, DT; WILLEMSE, PHB

    Piritrexim is a lipid-soluble antifolate which, like methotrexate, has a potent capacity to inhibit dihydrofolate reductase. We performed a multicentre phase 11 study with piritrexim in patients with locally advanced or metastatic breast cancer. Twenty-four patients of which sixteen had received

  13. A Pharmacokinetic Study of the Effects of Stress on Chemical Exposure.

    Science.gov (United States)

    2000-03-01

    strength of the immune system is also affected by stress in cancer progression studies done in humans (Delahanty, 1996:48). Robert Sapolsky has...146: 704- 712 (November 1997). Wester, R.C., D. Quan and H.I. Maibach. "In Vitro Percutaneous Absorption of Model Compounds Glyphosate and Malathion

  14. Andrographis paniculata: Dissolution investigation and pharmacokinetic studies of four major active diterpenoids after multiple oral dose administration in healthy Thai volunteers.

    Science.gov (United States)

    Pholphana, Nanthanit; Panomvana, Duangchit; Rangkadilok, Nuchanart; Suriyo, Tawit; Puranajoti, Porranee; Ungtrakul, Teerapat; Pongpun, Wanwisa; Thaeopattha, Saichit; Songvut, Phanit; Satayavivad, Jutamaad

    2016-12-24

    Andrographis paniculata is included in 'The National List of Essential Herbal Drugs A.D. 1999' of Thailand as an herbal drug for the treatment of common cold symptoms and non-infectious diarrhea. The therapeutic activities of A. paniculata are attributed to four major active diterpenoids: andrographolide (1), 14-deoxy-11, 12-didehydroandrographolide (2), neoandrographolide (3), and 14-deoxyandrographolide (4). However, the pharmacokinetic studies in humans of this plant were performed after a single oral dose administration and reported the parameters related to be of only 1. This study aims to determine the pharmacokinetic parameters of four major active diterpenoids after multiple oral dose administration of A. paniculata capsules in healthy volunteers. The dissolution testing of these four diterpenoids was also performed. The dissolution testing of four major active diterpenoids was conducted in pH 1.2, pH 4.5, and pH 6.8 for 10-100min. The pharmacokinetic study of these active diterpenoids was designed as an open-label, multiple oral dose administration of A. paniculata capsules in 20 healthy Thai volunteers at 1:1 ratio of female and male. Each volunteer was given four A. paniculata capsules each time which contained 1, 2, 3, and 4 in the quantities of 32.64, 5.40, 3.60, and 3.84mg, respectively, three times a day for three consecutive days. On the fourth day, after the first dose of the day was administered, blood samples were collected at the predefined time points. The validated LC-MS/MS method was used to simultaneously determine the concentrations of these diterpenoids in the human plasma samples. The pharmacokinetic parameters of each active diterpenoid were determined. All four major active diterpenoids have been completely dissolved in the simulated pH of gastrointestinal tract within 60min of dissolution. The dissolution profiles were found to be highest in pH 6.8 and lowest in pH 1.2, especially for 3. In the pharmacokinetic study, although 1 was

  15. Study on pharmacokinetics and tissue distribution of the isocorydine derivative (AICD) in rats by HPLC-DAD method

    Institute of Scientific and Technical Information of China (English)

    Yali Chen; Qian Yan; Mei Zhong; Quanyi Zhao; Junxi Liu; Duolong Di; Jinxia Liu

    2015-01-01

    A simple and effective high-performance liquid chromatography with diode-array detection method coupled with a liquid-liquid extraction pretreatment has been developed for determining the pharmacokinetics and tissue distribution of a novel structurally modified derivative(8-acetaminoisocorydine) of isocorydine.According to the in vivo experiments data calculations by DAS 2.0 software,a two-compartment metabolic model was suitable for describing the pharmacokinetic of 8-acetaminoisocorydine in rats.8-Acetamino-isocorydine was absorbed well after oral administration,and the absolute bioavailability was 76.5%.The half-life of 8-acetamino-isocorydine after intravenous and oral administration was 2.2 h and 2.0 h,respectively.In vivo,8-acetamino-isocorydine was highly distributed in the lungs,kidney and liver;however,relatively little entered the brain,suggesting that 8-acetaminoisocorydine could not easily pass through the blood brain barrier.Our work describes the first characterization of the pharmacokinetic parameters and tissue distribution of 8-acetamino-isocorydine.The acquired data will provide useful information for the in vivo pharmacology of 8-acetaminoisocorydine,and can be applied to new drug research.

  16. Non-clinical studies in the process of new drug development - Part II: Good laboratory practice, metabolism, pharmacokinetics, safety and dose translation to clinical studies.

    Science.gov (United States)

    Andrade, E L; Bento, A F; Cavalli, J; Oliveira, S K; Schwanke, R C; Siqueira, J M; Freitas, C S; Marcon, R; Calixto, J B

    2016-12-12

    The process of drug development involves non-clinical and clinical studies. Non-clinical studies are conducted using different protocols including animal studies, which mostly follow the Good Laboratory Practice (GLP) regulations. During the early pre-clinical development process, also known as Go/No-Go decision, a drug candidate needs to pass through several steps, such as determination of drug availability (studies on pharmacokinetics), absorption, distribution, metabolism and elimination (ADME) and preliminary studies that aim to investigate the candidate safety including genotoxicity, mutagenicity, safety pharmacology and general toxicology. These preliminary studies generally do not need to comply with GLP regulations. These studies aim at investigating the drug safety to obtain the first information about its tolerability in different systems that are relevant for further decisions. There are, however, other studies that should be performed according to GLP standards and are mandatory for the safe exposure to humans, such as repeated dose toxicity, genotoxicity and safety pharmacology. These studies must be conducted before the Investigational New Drug (IND) application. The package of non-clinical studies should cover all information needed for the safe transposition of drugs from animals to humans, generally based on the non-observed adverse effect level (NOAEL) obtained from general toxicity studies. After IND approval, other GLP experiments for the evaluation of chronic toxicity, reproductive and developmental toxicity, carcinogenicity and genotoxicity, are carried out during the clinical phase of development. However, the necessity of performing such studies depends on the new drug clinical application purpose.

  17. A validated LC-MS/MS determination method for the illegal food additive rhodamine B: Applications of a pharmacokinetic study in rats.

    Science.gov (United States)

    Cheng, Yung-Yi; Tsai, Tung-Hu

    2016-06-05

    Rhodamine B is an illegal and potentially carcinogenic food dye. The aim of this study was to develop a convenient, rapid, and sensitive UHPLC-MS/MS method for pharmacokinetic studies in rats. Rat plasma samples were deproteinized with acetonitrile and separated by UHPLC on a reverse-phase C18e column (100mm×2.1mm, 2μm) using a mobile phase consisting of methanol-5mM ammonium acetate (90:10, v/v). Detection was performed using a triple quadrupole tandem mass spectrometer in the selected reaction monitoring mode at [M](+) ion m/z 443.39→399.28 for rhodamine B and [M+H](+) ion m/z 253.17→238.02 for 5-methoxyflavone as the internal standard. This method was specific and produced linear results over a concentration range of 0.5-100ng/mL, with a lower limit of quantitation of 0.5ng/mL. All validation parameters, including the inter-day, intra-day, matrix effect, recovery, and stability in rat plasma, were acceptable according to the biological method validation guidelines developed by the FDA (2001). This method was successfully applied to a pharmacokinetic study in rats; oral administration of 1mg/kg of rhodamine B yielded a time to maximum concentration (Tmax) of 1.3±0.4h and an elimination half-life of 8.8±1.4h, with a clearance of 229.7±19.4mL/h/kg. These pharmacokinetic results provide a constructive contribution to our understanding of the absorption mechanism of rhodamine B and support additional food safety evaluations. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Pharmacokinetics of Stereoisomeric Dipeptide Prodrugs of Acyclovir Following Intravenous and Oral Administrations in Rats: A Study Involving In vivo Corneal Uptake of Acyclovir Following Oral Dosing

    Directory of Open Access Journals (Sweden)

    Ravi S.Talluri

    2009-10-01

    Full Text Available Objective: To delineate the plasma pharmacokinetics and determine the corneal uptake of valine based stereoisomeric dipeptide prodrugs of acyclovir (ACV in rats. Methods: Male Sprague-Dawley rats were used for the study. Pharmacokinetics of ACV, L-valine-acyclovir (LACV, L-valine- D-valine-acyclovir (LDACV and D-valine-L-valine acyclovir (DLACV prodrugs were delineated. These compounds were administered intravenously as a bolus via jugular vein cannula and orally by gavage. Samples were purified by protein precipitation method and analyzed by LC-MS/MS. Pertinent pharmacokinetic parameters were obtained by using WinNonlin. Corneal uptake studies of LDACV and LACV were studied following oral administration. Results: Following i.v. administration, the area under the curve (AUC in µM*min of generated ACV was in the order of LACV › LDACV › DLACV indicating their rate of metabolism. The AUC values of total drug obtained in the systemic circulation after oral administration LACV and LDACV were 1077.93 ± 236.09 and 1141.76 ± 73.67 µM*min, respectively. DLACV exhibited poor oral absorption. Cmax (µM and AUC of the intact prodrug obtained in the systemic circulation following oral administration of LDACV were almost 4–5 times higher than LACV. Moreover, concentrations achieved in the cornea after oral administration of LDACV were almost two times of LACV. Conclusions: LDACV increased both the oral bioavailability and subsequent in vivo corneal uptake of ACV. Hence, LDACV can be considered as the most promising drug candidate for delivery of ACV, in treatment of both genital herpes and ocular herpes keratitis after oral administration.

  19. Pharmacokinetics of Stereoisomeric Dipeptide Prodrugs of Acyclovir Following Intravenous and Oral Administrations in Rats: A Study Involving In vivo Corneal Uptake of Acyclovir Following Oral Dosing

    Science.gov (United States)

    Talluri, Ravi S.; Gaudana, Ripal; Hariharan, Sudharshan; Mitra, Ashim K.

    2009-01-01

    Objective To delineate the plasma pharmacokinetics and determine the corneal uptake of valine based stereoisomeric dipeptide prodrugs of acyclovir (ACV) in rats. Methods Male Sprague-Dawley rats were used for the study. Pharmacokinetics of ACV, L-valine-acyclovir (LACV), L-valine-D-valine-acyclovir (LDACV) and D-valine-L-valine acyclovir (DLACV) prodrugs were delineated. These compounds were administered intravenously as a bolus via jugular vein cannula and orally by gavage. Samples were purified by protein precipitation method and analyzed by LC-MS/MS. Pertinent pharmacokinetic parameters were obtained by using WinNonlin. Corneal uptake studies of LDACV and LACV were studied following oral administration. Results Following i.v. administration, the area under the curve (AUC) in μM*min of generated ACV was in the order of LACV > LDACV > DLACV indicating their rate of metabolism. The AUC values of total drug obtained in the systemic circulation after oral administration LACV and LDACV were 1077.93 ± 236.09 and 1141.76 ± 73.67 μM*min, respectively. DLACV exhibited poor oral absorption. Cmax (μM) and AUC of the intact prodrug obtained in the systemic circulation following oral administration of LDACV were almost 4–5 times higher than LACV. Moreover, concentrations achieved in the cornea after oral administration of LDACV were almost two times of LACV. Conclusions LDACV increased both the oral bioavailability and subsequent in vivo corneal uptake of ACV. Hence, LDACV can be considered as the most promising drug candidate for delivery of ACV, in treatment of both genital herpes and ocular herpes keratitis after oral administration. PMID:23861607

  20. Pharmacokinetics of Stereoisomeric Dipeptide Prodrugs of Acyclovir following Intravenous and Oral Administrations in Rats: A study Involving in vivo corneal Uptake of Acyclovir following Oral Dosing

    Directory of Open Access Journals (Sweden)

    Ravi S. Talluri

    2009-01-01

    Full Text Available Objective To delineate the plasma pharmacokinetics and determine the corneal uptake of valine based stereoisomeric dipeptide prodrugs of acyclovir (ACV in rats. Methods Male Sprague-Dawley rats were used for the study. Pharmacokinetics of ACV, L-valine-acyclovir (LACV, L-valine-D-valine-acyclovir (LDACV and D-valine-L-valine acyclovir (DLACV prodrugs were delineated. These compounds were administered intravenously as a bolus via jugular vein cannula and orally by gavage. Samples were purified by protein precipitation method and analyzed by LC-MS/MS. Pertinent pharmacokinetic parameters were obtained by using WinNonlin. Corneal uptake studies of LDACV and LACV were studied following oral administration. Results Following i.v. administration, the area under the curve (AUC in μM*min of generated ACV was in the order of LACV > LDACV > DLACV indicating their rate of metabolism. The AUC values of total drug obtained in the systemic circulation after oral administration LACV and LDACV were 1077.93 ± 236.09 and 1141.76 ± 73.67 μM*min, respectively. DLACV exhibited poor oral absorption. C max (μM and AUC of the intact prodrug obtained in the systemic circulation following oral administration of LDACV were almost 4–5 times higher than LACV. Moreover, concentrations achieved in the cornea after oral administration of LDACV were almost two times of LACV. Conclusions LDACV increased both the oral bioavailability and subsequent in vivo corneal uptake of ACV Hence, LDACV can be considered as the most promising drug candidate for delivery of ACV, in treatment of both genital herpes and ocular herpes keratitis after oral administration.

  1. A Phase I Study of the Safety and Pharmacokinetics of Higher-Dose Icotinib in Patients With Advanced Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Liu, Jian; Wu, Lihua; Wu, Guolan; Hu, Xingjiang; Zhou, Huili; Chen, Junchun; Zhu, Meixiang; Xu, Wei; Tan, Fenlai; Ding, Lieming; Wang, Yinxiang; Shentu, Jianzhong

    2016-11-01

    This phase I study evaluated the maximum tolerated dose, dose-limiting toxicities, safety, pharmacokinetics, and efficacy of icotinib with a starting dose of 250 mg in pretreated, advanced non-small cell lung cancer patients. We observed a maximum tolerated dose of 500 mg with a favorable pharmacokinetics profile and antitumor activity.These findings provide clinicians with evidence for application of higher-dose icotinib. Icotinib, an oral epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, has shown favorable tolerability and antitumor activity at 100-200 mg in previous studies without reaching the maximum tolerated dose (MTD). In July 2011, icotinib was approved by the China Food and Drug Administration at a dose of 125 mg three times daily for the treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) after failure of at least one platinum-based chemotherapy regimen. This study investigated the MTD, tolerability, and pharmacokinetics of higher-dose icotinib in patients with advanced NSCLC. Twenty-six patients with advanced NSCLC were treated at doses of 250-625 mg three times daily The EGFR mutation test was not mandatory in this study. Twenty-four (92.3%) of 26 patients experienced at least one adverse event (AE); rash (61.5%), diarrhea (23.1%), and oral ulceration (11.5%) were most frequent AEs. Dose-limiting toxicities were seen in 2 of 6 patients in the 625-mg group, and the MTD was established at 500 mg. Icotinib was rapidly absorbed and eliminated. The amount of time that the drug was present at the maximum concentration in serum (T max ) ranged from 1 to 3 hours (1.5-4 hours) after multiple doses. The t 1/2 was similar after single- and multiple-dose administration (7.11 and 6.39 hours, respectively). A nonlinear relationship was observed between dose and drug exposure. Responses were seen in 6 (23.1%) patients, and 8 (30.8%) patients had stable disease. This study demonstrated that higher

  2. Stable isotope in the pharmacokinetic studies of F-1594 as a non steroide anti-inflammatory

    International Nuclear Information System (INIS)

    Hanafiah Ws, A.; Badruzzaman, S.

    1983-01-01

    The use of deuterium(D 2 ) to aid the detection and identification of F-1594 as a new drug has been demonstrated in animal studies. The methods used in the detection and particularly for the quantitation of this drug from biological fluids are extremely sensitive. Mass fragmentography Selected Ion Monitoring(SIM) proves to be one of the most sensitive detection systems. Quantitation could be performed easily at a concentration as low as 10ng/ml plasma. Some of the more important factors which can influence the sensitivity, specivNficity and reliability of SIM measurement are discussed. (author)

  3. Pharmacokinetics of pregabalin controlled-release in healthy volunteers: effect of food in five single-dose, randomized, clinical pharmacology studies.

    Science.gov (United States)

    Chew, Marci L; Plotka, Anna; Alvey, Christine W; Pitman, Verne W; Alebic-Kolbah, Tanja; Scavone, Joseph M; Bockbrader, Howard N

    2014-09-01

    The pharmacokinetic properties of the immediate-release (IR) and the recently developed controlled-release (CR) formulation of pregabalin are dose proportional. Pregabalin IR can be taken with or without food. This analysis characterizes the effect of food on pregabalin CR. The objectives of this analysis were: (1) to evaluate the effect of administration time and fat or caloric content of an accompanying meal on the pharmacokinetic properties of a single dose of pregabalin CR (330 mg) relative to a single dose of pregabalin IR (300 mg); (2) to evaluate the pharmacokinetic properties of a single dose of pregabalin CR administered fasted relative to a single dose of pregabalin CR administered immediately after food; and (3) to determine the safety and tolerability of single-dose administration of pregabalin CR and IR with and without food. The effect of food on the pharmacokinetic properties of pregabalin CR was determined in five phase I, open-label, single-dose, crossover studies (24-28 participants/study). Caloric and fat content of meals were varied and treatments were administered in the morning, at midday, or in the evening. Blood samples were collected up to 48 h post-dose. Pharmacokinetic parameters were estimated from plasma concentration-time data using standard noncompartmental methods. Adverse events were monitored throughout all studies. One hundred and twenty-eight healthy participants (19-54 years of age) received pregabalin. Peak plasma concentrations (C max) were lower for CR than the respective pregabalin IR doses, and time to C max occurred later. When pregabalin CR was administered with food at midday or in the evening, total exposures [area under the plasma concentration-time curve from time zero extrapolated to infinite time (AUC∞)] were equivalent for pregabalin CR and IR formulations regardless of fat or caloric content. When pregabalin CR was administered with an 800-1,000 calorie medium-fat breakfast, AUC∞ was equivalent for

  4. Novel pharmacokinetic studies of the Chinese formula Huang-Lian-Jie-Du-Tang in MCAO rats.

    Science.gov (United States)

    Zhu, Huaxu; Qian, Zhilei; He, Feng; Liu, Mengzhu; Pan, Linmei; Zhang, Qichun; Tang, Yuping

    2013-07-15

    Our previous studies showed that after oral administration of an Huang-Lian-Jie-Du-Tang (HLJDT) decoction, there is a higher concentration of the pure components, berberine, baicalin and gardenoside in the plasma of Middle cerebral artery occlusion (MCAO) rats than in sham-operated rats, The aim of the present study was to determine whether these components could be reliably measured in MCAO rat tissues. First, the plasma concentration-time profiles of berberine, palmatine, baicalin, baicalein and gardenoside were characterised in MCAO rats after oral administration of the aqueous extract of HLJDT. Subsequently, liver, lung and kidney tissues were obtained from sudden death MCAO rats in the absorption phase (0.25 h), the distribution phase (1.0 h) and the elimination phase (8.0 h) after administration of the HLJDT aqueous extract. An HPLC method was developed and validated for the determination of the distribution characteristics of berberine, palmatine, baicalin, baicalein and gardenoside simultaneously from the above-mentioned rat tissues. The results indicated that berberine, palmatine, baicalin and baicalein distributed rapidly and accumulated at high levels in the lung, while gardenoside distributed widely in the lung and the kidney. To the best of our knowledge, this is the first report to describe the distribution of the active ingredients derived from HLJDT in MCAO rat tissues. The tissue distribution results provide a biopharmaceutical basis for the design of the clinic application of HLJDT in cerebrovascular disease. Copyright © 2012 Elsevier GmbH. All rights reserved.

  5. The tomato sauce making process affects the bioaccessibility and bioavailability of tomato phenolics: a pharmacokinetic study.

    Science.gov (United States)

    Martínez-Huélamo, Miriam; Tulipani, Sara; Estruch, Ramón; Escribano, Elvira; Illán, Montserrat; Corella, Dolores; Lamuela-Raventós, Rosa M

    2015-04-15

    Tomato sauce is the most commonly consumed processed tomato product worldwide, but very little is known about how the manufacturing process may affect the phenolic composition and bioavailability after consumption. In a prospective randomised, cross-over intervention study, we analysed the plasma and urinary levels of tomato phenolic compounds and their metabolites after acute consumption of raw tomatoes and tomato sauce, enriched or not with refined olive oil during production. Respectively, eleven and four phenolic metabolites were found in urine and plasma samples. The plasma concentration and urinary excretion of naringenin glucuronide were both significantly higher after the consumption of tomato sauce than raw tomatoes. The results suggest that the mechanical and thermal treatments during tomato sauce manufacture may help to deliver these potentially bioactive phenolics from the food matrix more effectively than the addition of an oil component, thus increasing their bioavailability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Experimental study on acute toxicity of Qingnao tablet to mice

    Science.gov (United States)

    Xie, Guoqi; Wang, Huamin; Ma, Zhenzhen; Hao, Shaojun; Li, Jun; Wang, Hongyu; Wen, Zhonghua; Zhang, Zhengchen

    2018-04-01

    To investigate the effect of Qingnao tablets on acute toxicity in mice. Forty mice, half male and half female, were randomly divided into normal saline group and Qingnao tablet group. After fasting for 12 hours, the mice were given 0. 4 ml / 10 g in maximum volume. In 1st, the rats were perfused 3 times (every 8 hours). The rats in the saline group were perfused with the same volume of saline in the same way. The mice were observed continuously within 3 hours and then every hour. The mice were given a normal diet for 14 consecutive days, and the changes of autonomous activity, reaction, diet, stool, secretion, eye and nose were observed daily. The mice fasted on the 13th day and weighed on the 14th day. And then put the mice to death, The changes of the liver, heart, spleen, lung, kidney, stomach, intestines, and brain were observed by the naked eye. There was no obvious abnormality in normal saline group. The autonomous activity of mice in the administration group decreased after initial administration, and gradually returned to normal after 2 hours of administration. On the day of administration, the stool of the mice became dark brown, and the feces returned to normal after 1.1 days of normal urination. No other mice had abnormal secretion, reaction, eye nose, diet, etc. On the 14th day, there were no visible heart, liver, spleen, lung, kidney, gastrointestinal tract in normal saline group and Qingnao tablet group. Abnormal changes in brain and other organs (edema, color, etc.). In the normal saline group and Qingnao tablet group, the initial weight of the mice was: 21.70 ± 0.97N 21.71 ± 1.13, and the weight of the mice on the 7th day was 29.70 ± 2.4c28.65 ± 3.11. On the 14th day, the body weight was 32.38 ± 3.40, 33.77 ± 3.82. Qingnao tablet has no obvious toxicity to the main organs of mice, so it can be considered safe in clinical use.

  7. Anti-cancer, pharmacokinetics and tumor localization studies of pH-, RF- and thermo-responsive nanoparticles.

    Science.gov (United States)

    Sanoj Rejinold, N; Thomas, Reju George; Muthiah, Muthunarayanan; Chennazhi, K P; Manzoor, K; Park, In-Kyu; Jeong, Yong Yeon; Jayakumar, R

    2015-03-01

    The curcumin-encapsulated chitosan-graft-poly(N-vinyl caprolactam) nanoparticles containing gold nanoparticles (Au-CRC-TRC-NPs) were developed by ionic cross-linking method. After "optimum RF exposure" at 40 W for 5 min, Au-CRC-TRC-NPs dissipated heat energy in the range of ∼42°C, the lower critical solution temperature (LCST) of chitosan-graft-poly(N-vinyl caprolactam), causing controlled curcumin release and apoptosis to cancer cells. Further, in vivo PK/PD studies on swiss albino mice revealed that Au-CRC-TRC-NPs could be sustained in circulation for a week with no harm to internal organs. The colon tumor localization studies revealed that Au-CRC-TRC-NPs were retained in tumor for a week. These results throw light on their feasibility as multi-responsive nanomedicine for RF-assisted cancer treatment modalities. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Pharmacokinetics of opicapone, a third-generation COMT inhibitor, after single and multiple oral administration: A comparative study in the rat

    Energy Technology Data Exchange (ETDEWEB)

    Gonçalves, Daniela [Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra (Portugal); CNC – Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra (Portugal); Alves, Gilberto, E-mail: gilberto@fcsaude.ubi.pt [CNC – Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra (Portugal); CICS-UBI – Health Sciences Research Centre, University of Beira Interior, Av. Infante D. Henrique, 6200-506 Covilhã (Portugal); Fortuna, Ana [Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra (Portugal); CNC – Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra (Portugal); Soares-da-Silva, Patrício [Department of Research and Development, BIAL – Portela & Ca S.A., Av. da Siderurgia Nacional, 4745-457 S. Mamede do Coronado (Portugal); MedInUP – Center for Drug Discovery and Innovative Medicines, University Porto, Porto (Portugal); Falcão, Amílcar [Laboratory of Pharmacology, Faculty of Pharmacy, University of Coimbra, Pólo das Ciências da Saúde, Azinhaga de Santa Comba, 3000-548 Coimbra (Portugal); CNC – Center for Neuroscience and Cell Biology, University of Coimbra, 3004-517 Coimbra (Portugal)

    2017-05-15

    Opicapone is a novel potent, reversible and purely peripheral catechol-O-methyltransferase inhibitor that has been developed to be used as an adjunct to levodopa/aromatic L-amino acid decarboxylase inhibitor therapy for Parkinson's disease. Thus, this study aimed to compare the plasma pharmacokinetics of opicapone and its active metabolite (BIA 9-1079) after the administration of single and multiple oral doses to rats. Wistar rats (n = 8 per group) were orally treated with single (30, 60 or 90 mg/kg) or multiple (30 mg/kg once-daily for seven consecutive days) oral doses of opicapone. Blood samples were collected up to 24 h post-dosing through a cannula introduced in the tail vein of rats. After quantifying opicapone and BIA 9-1079 in plasma, a non-compartmental pharmacokinetic analysis was performed. Opicapone was quickly absorbed (time to reach the maximum plasma concentration ≤ 2 h) in both dosage regimens and the extent of systemic exposure to opicapone increased approximately in a dose-proportional manner after single-dosing within the studied dose range (30–90 mg/kg). Opicapone and BIA 9-1079 showed a relatively short plasma elimination half-life (1.58–4.50 h) and a small systemic accumulation after multiple-dosing. Hence, no pharmacokinetic concerns are expected when opicapone is administered with a once-daily dosing regimen. - Highlights: • Opicapone is relatively rapid absorbed after oral administration to rats. • Systemic exposure to opicapone increases approximately in a dose-proportional manner. • Opicapone and BIA 9-1079 show a small systemic accumulation after multiple-dosing.

  9. Pharmacokinetics and Pharmacodynamics of Atazanavir in HIV-1-Infected Children Treated With Atazanavir Powder and Ritonavir: Combined Analysis of the PRINCE-1 and -2 Studies.

    Science.gov (United States)

    Sevinsky, Heather; Zaru, Luna; Wang, Reena; Xu, Xiaohui; Pikora, Cheryl; Correll, Todd A; Eley, Timothy

    2018-06-01

    Two clinical studies (PRINCE-1 and -2) in HIV-1-infected children assessed the safety, efficacy and pharmacokinetics of dual nucleos(t)ide reverse transcriptase inhibitor background therapy plus once-daily atazanavir (ATV) powder formulation boosted with ritonavir (ATV + RTV). Here, we present a combined analysis of ATV pharmacokinetics and pharmacodynamics across these studies. Intensive 24-hour pharmacokinetic profiles at steady state compared ATV exposures (area under the concentration-time curve in one dosing interval) in 5 ATV + RTV baseline weight-band dosing categories, with historic data in adults receiving ATV + RTV 300/100 mg capsules. Repeated ATV Ctrough measurements over 48 weeks explored relationships between ATV composite Ctrough quartiles (CCQs) with virologic efficacy and key safety parameters. Of 146 children included in this combined analysis, 49.3% were male, 56.8% were Black/African American and 62.3% were antiretroviral experienced. Proportions with HIV-1 RNA <50 copies/mL at week 48 were 13/32, 24/32, 19/32 and 13/28 in the lowest through highest ATV CCQs, respectively. Mean changes from baseline in total bilirubin at week 48 were +0.3, +0.5, +0.6 and +1.0 mg/dL in the lowest through highest ATV CCQs, respectively. Corresponding proportions with adverse events of hyperbilirubinemia by week 48 were 1/36, 4/36, 5/36 and 13/35, respectively. Changes from baseline in total amylase or electrocardiogram parameters and adverse events of diarrhea did not vary by ATV CCQs. Weight-band dosing of ATV + RTV plus optimized dual nucleos(t)ide reverse transcriptase inhibitors in young HIV-1-infected children achieved similar ATV exposure to that in adults; no unexpected safety findings occurred, and with the exception of lower virologic suppression in the lowest ATV CCQ, there was no apparent trend in virologic suppression across ATV CCQs.

  10. LC-MS/MS Determination and Pharmacokinetic Study of Pedunculoside in Rat Plasma after Oral Administration of Pedunculoside and Ilex rotunda Extract

    Directory of Open Access Journals (Sweden)

    Waiou Zhao

    2015-05-01

    Full Text Available Ilex rotunda is widely used to treat many disorders as a traditional Chinese medicine (TCM containing 4%–5% pedunculoside (PDC. A rapid, selective, and sensitive liquid chromatography-tandem mass spectrometry method (LC-MS/MS was developed and validated to determine PDC in rat plasma by using 3β,19α-dihydroxyurs-12-en-28-oic acid 28-β-D-glucopyranosyl ester (DEOG as an internal standard. The analytes were extracted by protein precipitation and eluted on a C18 chromatography column using a mobile phase of methanol–H2O (70:30, v/v delivered at a flow rate of 0.6 mL/min. Detection was performed using positive ion electrospray ionization in multiple reaction monitoring modes. The assay was linear over the concentration range of 0.60 ng/mL to 200 ng/mL, with a quantification limit of 0.60 ng/mL. Intra-day and inter-day precisions (%RSD ranged from 2.12 to 9.51 for PDC, whereas the accuracy was within −7.83%~9.40%. The validated method was successfully applied to the pharmacokinetic study of PDC in rat plasma after oral administration of pure PDC and Ilex rotunda extract (IRE. Pharmacokinetic parameters of PDC in IRE, such as Cmax, AUC0–t, AUC0–∞, t1/2z, and CLz/F, statistically differed from those of the pure monomer (p < 0.01. However, Tmax and MRT showed no significant differences between the two groups. Results suggested that other coexisting components in IRE may decrease the absorption of PDC. Compound-compound interactions between PDC and other herbal extract components can alter the pharmacokinetic behavior of PDC. The study will be helpful in providing references for understanding the action mechanism and clinical application of Ilex rotunda.

  11. Elucidating the in vivo fate of nanocrystals using a physiologically based pharmacokinetic model: a case study with the anticancer agent SNX-2112

    Directory of Open Access Journals (Sweden)

    Dong D

    2015-03-01

    Full Text Available Dong Dong,1* Xiao Wang,1* Huailing Wang,1 Xingwang Zhang,2 Yifei Wang,1 Baojian Wu2 1Guangzhou Jinan Biomedicine Research and Development Center, 2Division of Pharmaceutics, College of Pharmacy, Jinan University, Guangzhou, People’s Republic of China *These authors contributed equally to this work Introduction: SNX-2112 is a promising anticancer agent but has poor solubility in both water and oil. In the study reported here, we aimed to develop a nanocrystal formulation for SNX-2112 and to determine the pharmacokinetic behaviors of the prepared nanocrystals. Methods: Nanocrystals of SNX-2112 were prepared using the wet-media milling technique and characterized by particle size, differential scanning calorimetry, drug release, etc. Physiologically based pharmacokinetic (PBPK modeling was undertaken to evaluate the drug’s disposition in rats following administration of drug cosolvent or nanocrystals. Results: The optimized SNX-2112 nanocrystals (with poloxamer 188 as the stabilizer were 203 nm in size with a zeta potential of -11.6 mV. In addition, the nanocrystals showed a comparable release profile to the control (drug cosolvent. Further, the rat PBPK model incorporating the parameters of particulate uptake (into the liver and spleen and of in vivo drug release was well fitted to the experimental data following administration of the drug nanocrystals. The results reveal that the nanocrystals rapidly released drug molecules in vivo, accounting for their cosolvent-like pharmacokinetic behaviors. Due to particulate uptake, drug accumulation in the liver and spleen was significant at the initial time points (within 1 hour. Conclusion: The nanocrystals should be a good choice for the systemic delivery of the poorly soluble drug SNX-2112. Also, our study contributes to an improved understanding of the in vivo fate of nanocrystals. Keywords: intravenous delivery, PBPK, tissue distribution, poloxamer 188

  12. The Lack of Effect of Food on the Pharmacokinetics of ZX008 (Fenfluramine Oral Solution): Results of a Single-dose, Two-period Crossover Study.

    Science.gov (United States)

    Gammaitoni, Arnold; Smith, Steven; Boyd, Brooks

    2018-06-22

    Fenfluramine is being developed as a low-dose adjunctive treatment for seizures in patients with Dravet syndrome and other epileptic encephalopathies, including Lennox-Gastaut syndrome. Most patients with Dravet syndrome receive multiple antiepileptic drugs, making it challenging for caregivers to track correct administration times. The present Phase I study was conducted to determine the effect of food on the pharmacokinetic properties of fenfluramine. Healthy nonsmoking subjects aged 18 to 50years were enrolled in an open-label, crossover, Phase I pharmacokinetic and safety profile study and received 2 single 0.8-mg/kg doses of ZX008 (fenfluramine hydrochloride oral solution), 1 after a 10-hour overnight fast and the other 30 minutes after the start of consumption of a high-fat breakfast, in a randomly assigned order. A washout period of at least 9days separated the 2 treatment periods. Venous blood samples were taken before each dose and periodically for 72hours after each dose for determination of concentrations of fenfluramine and its active metabolite norfenfluramine. Plasma pharmacokinetic parameters were estimated for each subject by noncompartmental analysis. In the 13 subjects completing both treatment periods, food had no effect on the rate or extent of absorption and bioavailability of fenfluramine as assessed by fed vs fasted adjusted geometric mean observed plasma C max (59.1vs 56.7 ng/mL; NS) and AUC 0-∞ (1640vs 1600 ng · h/mL; NS). Additionally, there was no impact of food on systemic exposure of norfenfluramine. Seven subjects reported at least 1 treatment-emergent adverse event; all treatment-emergent adverse events were mild in severity. The bioequivalence and tolerability of single 0.8-mg/kg oral doses of ZX008 in the fed and fasted states support ZX008 administration without regard to meals. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  13. A phase 1 randomized study evaluating the effect of omeprazole on the pharmacokinetics of a novel 5-hydroxytryptamine receptor 4 agonist, revexepride (SSP-002358), in healthy adults

    Science.gov (United States)

    Pierce, David; Corcoran, Mary; Velinova, Maria; Hossack, Stuart; Hoppenbrouwers, Mieke; Martin, Patrick

    2015-01-01

    Background About 30% of patients with gastroesophageal reflux disease continue to experience symptoms despite treatment with proton pump inhibitors. The 5-hydroxytryptamine 4 receptor agonist revexepride (SSP-002358) is a novel prokinetic that stimulates gastrointestinal motility, which has been suggested as a continued cause of symptoms in these patients. The aim of this study was to assess whether revexepride pharmacokinetics were affected by co-administration of omeprazole, in preparation for a proof-of-concept evaluation of revexepride added to proton pump inhibitor treatment. Methods In this phase 1, open-label, randomized, two-period crossover study, healthy adults aged 18–55 years were given a single dose of revexepride 1 mg or revexepride 1 mg + omeprazole 40 mg. Pharmacokinetic parameters were assessed for up to 48 hours after administration of the investigational product. Adverse events, clinical chemistry and hematology parameters, electrocardiograms, and vital signs were monitored. Results In total, 42 participants were enrolled and 40 completed the study. The median age was 24 years (18–54 years), 55% were women and 93% were white. The pharmacokinetic parameters of revexepride were similar without or with omeprazole co-administration. The mean area under the plasma concentration–time curve from time 0 to infinity (AUC0–∞) was 23.3 ng · h/mL (standard deviation [SD]: 6.33 ng · h/mL) versus 24.6 ng · h/mL (SD: 6.31 ng · h/mL), and maximum plasma concentrations (Cmax) were 3.89 ng/mL (SD: 1.30 ng/mL) and 4.12 ng/mL (SD: 1.29 ng/mL) in participants without and with omeprazole, respectively. For AUC0–∞ and Cmax, the 90% confidence intervals for the ratios of geometric least-squares means (with:without omeprazole) were fully contained within the pre-defined equivalence limits of 0.80–1.25. Mean apparent terminal phase half-life was 9.95 hours (SD: 2.06 hours) without omeprazole, and 11.0 hours (SD: 3.25 hours) with omeprazole. Conclusion

  14. Pharmacokinetic Profiles of Active Ingredients and Its Metabolites Derived from Rikkunshito, a Ghrelin Enhancer, in Healthy Japanese Volunteers: A Cross-Over, Randomized Study.

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    Hiroyuki Kitagawa

    Full Text Available Rikkunshito, a traditional Japanese (Kampo medicine, has been used to treat upper gastrointestinal disorders such as functional dyspepsia and gastroesophageal reflux. This study investigated the exposure and pharmacokinetics of the ingredients of rikkunshito in healthy volunteers.First, an exploratory nonrandomized, open-label, one-period, noncrossover study using four healthy Japanese volunteers to detect 32 typical ingredients of rikkunshito in plasma and urine. As a result, 18 or 21 of 32 ingredients was detected in plasma or urine samples after oral administration of rikkunshito (7.5 g/day. Furthermore, a randomized, open-label, three-arm, three-period, crossover study using 21 subjects was conducted to determine the amounts of exposure and pharmacokinetic parameters of nine ingredients derived from rikkunshito (atractylodin, atractylodin carboxylic acid, pachymic acid, 3,3',4',5,6,7,8-heptamethoxyflavone, naringenin, nobiletin, liquiritigenin, isoliquiritigenin, and 18β-glycyrrhetinic acid after oral administration of rikkunshito at three different doses (2.5, 5.0, or 7.5 g/day during each period. The pharmacokinetic profiles of the nine ingredients in plasma were characterized. The geometric means (95% confidence interval for the Cmax of the ingredients at a dose of 7.5 g were 1570 (1210-2040, 14,300 (12,200-16,800, 91.0 (71.8-115, 105 (75.6-144, 1150 (802-1650, 35.9 (24.6-52.5, 800 (672-952, 42.8 (30.4-60.3, and 55,600 (39,600-78,100 pg/mL, respectively, and for the AUC0-last were 1760 (1290-2390, 12700 (11,100-14,600, 1210 (882-1650, 225 (157-322, 4630 (2930-7320, 35.7 (20.4-62.7, 4040 (3260-5010, 122 (88.2-168, and 832,000 (628,000-1,100,000 pg·h/mL respectively.We identified the ingredients of rikkunshito that are absorbed in humans. Furthermore, we determined the pharmacokinetics of nine ingredients derived from rikkunshito. This information will be useful for elucidating the pharmacological effects of rikkunshito

  15. Nanosizing of valsartan by high pressure homogenization to produce dissolution enhanced nanosuspension: pharmacokinetics and pharmacodyanamic study.

    Science.gov (United States)

    Gora, Shayana; Mustafa, Gulam; Sahni, Jasjeet Kaur; Ali, Javed; Baboota, Sanjula

    2016-01-01

    The purpose of the present study was to formulate and evaluate nanosuspension of Valsartan (VAL), a poorly water soluble and low bioavailable drug (solubility of 0.18 mg mL(-1); 23% of oral bioavailability) with the aim of improving the aqueous solubility thus the bioavailability and consequently better anti-hypertensive activity. Valsartan nanosuspension (VAL-NS) was prepared using high-pressure homogenization followed by lyophilisation. The screening of homogenization factors influencing nanosuspension was done by 3-factorial, 3-level Box-Behnken statistical design. Model suggested the influential role of homogenization pressure and cycles on drug nanosizing. The optimized formulation containing Poloxamer(-1)88 (PXM 188) was homogenized for 2 cycles at 500 and 1000 bar, followed by 5 cycles at 1500 bars. The size analysis and transmission electron microscopy showed nanometric size range and uniform shape of the nanosuspension. The in vitro dissolution showed an enhanced release of VAL from nanosuspension (VAL-NS) compared to physical mixture with PXM 188. Pharmacodynamic results showed that, oral administration of VAL-NS significantly lowered (p ≤ 0.001) blood pressure in comparison to non-homogenized VAL (VAL-Susp) in Wistar rat. The level of VAL in rat plasma treated with VAL-NS showed significant difference (p ≤ 0.005) in Cmax (1627.47 ± 112.05 ng mL(-1)), Tmax (2.00 h) and AUC0→24 (13279.2 ± 589.426 ng h mL(-1)) compared to VAL-Susp that was found to be 1384.73 ± 98.76 ng mL(-1), 3.00 h and 9416.24 ± 218.48 ng h mL(-1) respectively. The lower Tmax value, proved the enhanced dissolution rate of VAL. The overall results proved that newly developed VAL-NS increased the plasma bioavailability and pharmacodyanamic potential over the reference formulation containing crude VAL.

  16. Changes in ceftriaxone pharmacokinetics/pharmacodynamics during the early phase of sepsis: a prospective, experimental study in the rat

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    Valentina Selmi

    2016-11-01

    Full Text Available Abstract Background Sepsis is characterized by the loss of the perm-selectivity properties of the glomerular filtration barrier (GFB with consequent albuminuria. We examined whether the pharmacokinetics–pharmacodynamics (PK/PD of ceftriaxone (CTX, an extensively protein-bound 3rd generation cephalosporin, is altered during early sepsis and whether an increase in urinary loss of bound-CTX, due to GFB alteration, can occur in this condition. Methods A prospective, experimental, randomized study was carried out in adult male Sprague–Dawley rats. Sepsis was induced by cecal ligation and puncture (CLP. Rats were divided into two groups: Sham-operated and CLP. CTX (100 mg i.p., equivalent to 1 g dose in humans was administered in order to measure plasma and lung CTX concentrations at several time-points: baseline and 1, 2, 4 and 6 h after administration. CTX was measured by High Performance Liquid Chromatography (HPLC. The morphological status of the sialic components of the GFB barrier was assessed by lectin histo-chemistry. Monte Carlo simulation was performed to calculate the probability of target attainment (PTA >90% for 80 and 100% of Tfree > minimum inhibitory concentration (MIC for 80 and 100% of dosing interval. Measurements and main results After CLP, sepsis developed in rats as documented by the growth of polymicrobial flora in the peritoneal fluid (≤1 × 101 CFU in sham rats vs 5 × 104–1 × 105 CFU in CLP rats. CTX plasma concentrations were higher in CLP than in sham rats at 2 and 4 h after administration (difference at 2 h was 47.3, p = 0.012; difference at 4 h was 24.94, p = 0.004, while lung penetration tended to be lower. An increased urinary elimination of protein-bound CTX occurred (553 ± 689 vs 149 ± 128 mg/L, p  90% for 100% of the dosing interval was reached neither for sham nor CLP rats using MIC = 1 mg/L, the clinical breakpoint for Enterobacteriacee. Conclusions Sepsis causes changes in

  17. The preparation, characterization, and pharmacokinetic studies of chitosan nanoparticles loaded with paclitaxel/dimethyl-β-cyclodextrin inclusion complexes

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    Ye YJ

    2015-07-01

    Full Text Available Ya-Jing Ye,1 Yun Wang,1 Kai-Yan Lou,1 Yan-Zuo Chen,1 Rongjun Chen,2 Feng Gao1,3,4 1Department of Pharmaceutics, School of Pharmacy, East China University of Science and Technology, Shanghai, People’s Republic of China; 2Department of Chemical Engineering, Imperial College London, London, United Kingdom; 3Shanghai Key Laboratory of Functional Materials Chemistry, 4Shanghai Key Laboratory of New Drug Design, East China University of Science and Technology, Shanghai, People’s Republic of China Abstract: A novel biocompatible and biodegradable drug-delivery nanoparticle (NP has been developed to minimize the severe side effects of the poorly water-soluble anticancer drug paclitaxel (PTX for clinical use. PTX was loaded into the hydrophobic cavity of a hydrophilic cyclodextrin derivative, heptakis (2,6-di-O-methyl-β-cyclodextrin (DM-β-CD, using an aqueous solution-stirring method followed by lyophilization. The resulting PTX/DM-β-CD inclusion complex dramatically enhanced the solubility of PTX in water and was directly incorporated into chitosan (CS to form NPs (with a size of 323.9–407.8 nm in diameter using an ionic gelation method. The formed NPs had a zeta potential of +15.9–23.3 mV and showed high colloidal stability. With the same weight ratio of PTX to CS of 0.7, the loading efficiency of the PTX/DM-β-CD inclusion complex-loaded CS NPs was 30.3-fold higher than that of the PTX-loaded CS NPs. Moreover, it is notable that PTX was released from the DM-β-CD/CS NPs in a sustained-release manner. The pharmacokinetic studies revealed that, compared with reference formulation (Taxol®, the PTX/DM-β-CD inclusion complex-loaded CS NPs exhibited a significant increase in AUC0→24h (the area under the plasma drug concentration–time curve over the period of 24 hours and mean residence time by 2.7-fold and 1.4-fold, respectively. Therefore, the novel drug/DM-β-CD inclusion complex-loaded CS NPs have promising applications for the

  18. Reversal of P-glycoprotein-medicated multidrug resistance by LBM-A5 in vitro and a study of its pharmacokinetics in vivo.

    Science.gov (United States)

    Zhao, Tianxiao; Song, Yun; Liu, Baomin; Qiu, Qianqian; Jiao, Lei; Li, Yunman; Huang, Wenlong; Qian, Hai

    2015-01-01

    The overexpression of P-glycoprotein (P-gp) in tumors leads to multidrug resistance (MDR), which is a significant obstacle in clinical cancer chemotherapy. The co-administration of anticancer drugs and MDR modulators is a promising strategy for overcoming this problem. Our study aimed to explore the reversal mechanism and safety of the MDR modulator LBM-A5 in vitro, and evaluate its pharmacokinetics and effects on doxorubicin metabolism in vivo. We evaluated an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay of anticancer agents mediated by LBM-A5, the effect of LBM-A5 on rhodamine123 intracellular accumulation, and the efflux in K562/DOX cells to investigate the reversal mechanisms of LBM-A5. The results showed that LBM-A5 inhibits rhodamine123 efflux and increases intracellular accumulation by inhibiting the efflux pump function of P-gp. Furthermore, the therapeutic index and CYP3A4 activity analysis in vitro suggested that LBM-A5 is reasonably safe to use. Also, LBM-A5 (10 mg/kg body mass) achieved the required plasma concentration in sufficient time to reverse MDR in vivo. Importantly, the LBM-A5 treatment group shared similar doxorubicin (DOX) pharmacokinetics with the free DOX group. Our results suggest that LBM-A5 effectively reverses MDR (EC50 = 483.6 ± 81.7 nmol·L(-1)) by inhibiting the function of P-gp, with relatively ideal pharmacokinetics and in a safe manner, and so may be a promising candidate for cancer chemotherapy research.

  19. Development and validation of an LC–MS/MS method for quantification of NC-8 in rat plasma and its application to pharmacokinetic studies

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    Baxter Hepburn Kachingwe

    2018-01-01

    Full Text Available ent-16-Oxobeyeran-19-N-methylureido (NC-8 is a recently synthesized derivative of isosteviol that showed anti-hepatitis B virus (HBV activity by disturbing replication and gene expression of the HBV and by inhibiting the host toll-like receptor 2/nuclear factor-κB signaling pathway. To study its pharmacokinetics as a part of the drug development process, a highly sensitive, rapid, and reliable liquid chromatography tandem mass spectrometry (LC–MS/MS method was developed and validated for determining NC-8 in rat plasma. After protein precipitation extraction, the chromatographic separation of the analyte and internal standard (IS; diclofenac sodium was performed on a reverse-phase Luna C18 column coupled with a Quattro Ultima triple quadruple mass spectrometer in the multiple-reaction monitoring mode using the transitions, m/z 347.31 → 75.09 for NC-8 and m/z 295.89 → 214.06 for the IS. The lower limit of quantitation was 0.5 ng/mL. The linear scope of the standard curve was between 0.5 and 500 ng/mL. Both the precision (coefficient of variation; % and accuracy (relative error; % were within acceptable criteria of <15%. Recoveries ranged from 104% to 113.4%, and the matrix effects (absolute were non-significant (CV ≤ 6%. The validated method was successfully applied to investigate the pharmacokinetics of NC-8 in male Sprague–Dawley rats. The present methodology provides an analytical means to better understand the preliminary pharmacokinetics of NC-8 for investigations on further drug development.

  20. Using Akaike's information theoretic criterion in mixed-effects modeling of pharmacokinetic data: a simulation study [version 3; referees: 2 approved, 1 approved with reservations

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    Erik Olofsen

    2015-07-01

    Full Text Available Akaike's information theoretic criterion for model discrimination (AIC is often stated to "overfit", i.e., it selects models with a higher dimension than the dimension of the model that generated the data. However, with experimental pharmacokinetic data it may not be possible to identify the correct model, because of the complexity of the processes governing drug disposition. Instead of trying to find the correct model, a more useful objective might be to minimize the prediction error of drug concentrations in subjects with unknown disposition characteristics. In that case, the AIC might be the selection criterion of choice. We performed Monte Carlo simulations using a model of pharmacokinetic data (a power function of time with the property that fits with common multi-exponential models can never be perfect - thus resembling the situation with real data. Prespecified models were fitted to simulated data sets, and AIC and AICc (the criterion with a correction for small sample sizes values were calculated and averaged. The average predictive performances of the models, quantified using simulated validation sets, were compared to the means of the AICs. The data for fits and validation consisted of 11 concentration measurements each obtained in 5 individuals, with three degrees of interindividual variability in the pharmacokinetic volume of distribution. Mean AICc corresponded very well, and better than mean AIC, with mean predictive performance. With increasing interindividual variability, there was a trend towards larger optimal models, but with respect to both lowest AICc and best predictive performance. Furthermore, it was observed that the mean square prediction error itself became less suitable as a validation criterion, and that a predictive performance measure should incorporate interindividual variability. This simulation study showed that, at least in a relatively simple mixed-effects modelling context with a set of prespecified models

  1. Pharmacokinetic study of harmane and its 10 metabolites in rat after intravenous and oral administration by UPLC-ESI-MS/MS.

    Science.gov (United States)

    Li, Shuping; Teng, Liang; Liu, Wei; Cheng, Xuemei; Jiang, Bo; Wang, Zhengtao; Wang, Chang-Hong

    2016-09-01

    Context The β-carboline alkaloid harmane is widely distributed in common foods, beverages and hallucinogenic plants. Harmane exerts potential in therapies for Alzheimer's and depression diseases. However, little information on its dynamic metabolic profiles and pharmacokinetics in vivo is currently available. Objective This study investigates the dynamic metabolic profiles and pharmacokinetic properties of harmane and its metabolites in rats in vivo. Materials and methods A highly selective, sensitive and rapid ultra-performance liquid chromatography combined with electrospray ionization tandem mass spectrometry (UPLC-ESI-MS/MS) method was developed and well-validated for simultaneous quantitative determination of harmane and its uncertain endogenous metabolite harmine, as well as for semiquantitative determination of 10 harmane metabolites in rats after intravenous injection and oral administration of harmane at 1.0 and 30.0 mg/kg, respectively. Results The calibration curves of harmane and harmine showed excellent linearity within the concentration range of 1-2000 ng/mL with acceptable accuracy, precision, selectivity, recovery, matrix effect and stability. Ten metabolites, including harmane but not harmine, were detected and identified after intravenous and oral administration of harmane. The absolute bioavailability of harmane following an oral dose was 19.41 ± 3.97%. According to the AUC0-t values of all the metabolites, the metabolic levels of phase II metabolites were higher than those of phase I metabolites, and the sulphation pathways were the dominant metabolic routes for harmane in both routes of administration. Discussion and conclusion The pharmacokinetic properties of harmane and its 10 metabolites in rats were determined. Sulphate conjugation was the predominant metabolic process of harmane in rats.

  2. Pharmacokinetics of {sup 99m}Tc-MAG{sub 3} and {sup 131}I-OIH. Comparative study based on 2 compartment model analysis

    Energy Technology Data Exchange (ETDEWEB)

    Shuke, Noriyuki; Takashio, Tetsuya; Sato, Junichi [Asahikawa Medical Coll., Hokkaido (Japan). Hospital] [and others

    1996-05-01

    We studied 50 patients with mild to moderate renal dysfunction to compare pharmacokinetics of {sup 99m}Tc-MAG{sub 3} with that of {sup 131}I-OIH. After simultaneous bolus injection of both {sup 99m}Tc-MAG{sub 3} and {sup 131}I-OIH, 8-point venous blood sampling was performed from 2 to 44 min post injection. Aliquoted plasma samples were counted for radioactivity along with the injected standard to obtain % injected dose/ml plasma for each tracer. Using obtained time-concentration data, classical 2 compartment model analysis was performed for both tracers to obtain various pharmacokinetic parameters, including distribution volumes (Vds), intercompartmental rate constants, and plasma clearance. In these parameters, Vd of central compartment, Vd at steady state, central to peripheral inter-compartmental rate constant, and plasma clearance were significantly larger for {sup 131}I-OIH. In all parameters, significant correlation was found between {sup 99m}Tc-MAG{sub 3} and {sup 131}I-OIH. The best correlation was seen in plasma clearance (r=0.891, p<0.0001). Plasma clearance ratio ({sup 99m}Tc-MAG{sub 3}/{sup 131}I-OIH), however, showed weak but significant negative correlation with serum creatinine, although this correlation was not likely to affect the overall correlation of clearance between {sup 131}I-OIH and {sup 99m}Tc-MAG{sub 3}. From these results, we comfirmed that {sup 99m}Tc-MAG{sub 3} clearance could be used as an alternative to {sup 131}I-OIH clearance, although pharmacokinetic behavior of {sup 99m}Tc-MAG{sub 3} was not exactly the same as that of {sup 131}I-OIH. (author)

  3. A simple and sensitive method for determination of vitamins D3 and K1 in rat plasma: application for an in vivo pharmacokinetic study.

    Science.gov (United States)

    Gershkovich, Pavel; Ibrahim, Fady; Sivak, Olena; Darlington, Jerald W; Wasan, Kishor M

    2014-03-01

    To develop and to validate a simple but sensitive method for determination of vitamins D3 and K1 in rat plasma. The sample treatment included protein precipitation by cold acetonitrile, evaporation, reconstitution with methanol and filtration. The chromatography conditions included Xterra RP18 3.5 µm 4.6 × 100 mm column at ambient temperature and mobile phase consisting of methanol/water (93/7, v/v) at 0.5 mL/min flow rate. Vitamin D3 and probucol were detected at 265 nm and vitamin K1 at 239 nm. Rats were administered intravenously by 0.1 mg/kg of vitamin D3 or K1 and the blood samples were withdrawn pre-administration and at pre-determined time points post-administration. The pharmacokinetic analysis was performed using a non-compartmental approach. The calibration curves in rat plasma were linear up to 5000 ng/mL for both vitamins. The limit of quantification (LOQ) was 20 ng/mL for vitamin D3 and 40 ng/mL for K1. Inter- and intra-day precision and accuracy were below 15%. The pharmacokinetic parameters of vitamin D3 following intravenous administration were: AUC0-∞ = 11323 ± 1081 h × ng/mL, Vd = 218 ± 80 mL/kg, CL = 8.9 ± 0.8 mL/h/kg, t1/2 = 16.8 ± 5 h; and of vitamin K1: AUC0-∞ = 2495 ± 297 h × ng/mL, Vd = 60 ±24 mL/kg, CL = 40.5 ± 5.1 mL/h/kg, t1/2 = 1.1 ±0.5 h. The developed HPLC-UV assay is a simple and sensitive method for the determination of vitamins D3 and K1 in rat plasma. A higher dose of vitamin K1 should be used in future studies for accurate estimation of pharmacokinetic parameters. The data show the suitability of the assay for pharmacokinetic studies in rats.

  4. Pharmacokinetic Study of a Diclofenac Sodium Capsule Filled with Enteric-coated Pellets in Healthy Chinese Volunteers by Liquid Chromatography-electrospray Ionization-tandem Mass Spectrometry.

    Science.gov (United States)

    Ma, J-Y; Liu, M; Yang, M; Zhao, H; Tong, Y; Zhang, Y; Deng, M; Liu, H

    2016-05-01

    The pharmacokinetic study of a diclofenac sodium capsule filled with enteric-coated pellets (abbreviated as CAPSULE) in healthy Chinese subjects was evaluated using liquid chromatography-electrospray ionization-tandem mass spectrometry with simple sample preparation. In a cross-over study, 12 healthy male volunteers were given 50 mg CAPSULE and diclofenac sodium enteric-coated tablet (abbreviated as TABLET, used as a control dosage form) at fasting. The Cmax, AUC0-t, and Tmax of CAPSULE were 1.01±0.52 μg/mL, 1.54±0.18 μg·h/mL, and 1.50±1.31 h, respectively. When compared with TABLET, the pharmacokinetic study showed that although this CAPSULE exhibited similar AUC (only 10% lower), it presented lower maximum plasma concentration, faster absorption and shorter time to reach maximum concentration. When compared with the previous study in Germany, obvious variations on Tmax were found in Chinese subjects taking CAPSULE, but not TABLET. The results indicated that individual difference should be paid attention when prescribing CAPSULE to Chinese patients. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Pharmacokinetics of drugs in pregnancy.

    Science.gov (United States)

    Feghali, Maisa; Venkataramanan, Raman; Caritis, Steve

    2015-11-01

    Pregnancy is a complex state where changes in maternal physiology have evolved to favor the development and growth of the placenta and the fetus. These adaptations may affect preexisting disease or result in pregnancy-specific disorders. Similarly, variations in physiology may alter the pharmacokinetics or pharmacodynamics that determines drug dosing and effect. It follows that detailed pharmacologic information is required to adjust therapeutic treatment strategies during pregnancy. Understanding both pregnancy physiology and the gestation-specific pharmacology of different agents is necessary to achieve effective treatment and limit maternal and fetal risk. Unfortunately, most drug studies have excluded pregnant women based on often-mistaken concerns regarding fetal risk. Furthermore, over two-thirds of women receive prescription drugs while pregnant, with treatment and dosing strategies based on data from healthy male volunteers and non-pregnant women, and with little adjustment for the complex physiology of pregnancy and its unique disease states. This review will describe basic concepts in pharmacokinetics and their clinical relevance and