Displaying publications 41 - 60 of 86 in total

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  1. Hanachi P, Loh LN, Fauziah O, Rafiuz ZH, Tee ST, Lye CW, et al.
    Med J Malaysia, 2004 May;59 Suppl B:208-9.
    PMID: 15468891
    Neem, Azadirachta indica, is a plant from the family Meliaceae, known as "Pokok Semambu" in Malay community. It has been extensively used in India as traditional Ayurvedic and folklore minedicine for the treatment of various diseases. This study aimed to determine the distribution of selenium in the liver of rats during hepatocarcinogenesis when neem aqueous extract and dietary selenium was supplemented.
    Matched MeSH terms: Tissue Distribution
  2. Chan MP, Mohd MA
    Environ Toxicol, 2005 Feb;20(1):45-52.
    PMID: 15712329
    A method has been developed for the determination of trace levels of alpha-endosulfan, beta-endosulfan, endosulfan sulfate, and endosulfan diol in rat plasma and tissue samples. Endosulfan and its metabolites in the plasma samples were extracted with solid-phase extraction Chromabond-end-capped C18 cartridges and analyzed by a Shimadzu QP-5050A gas chromatograph-mass spectrometer (GCMS) with quadrupole detector in selected-ion-monitoring mode. The analysis of endosulfan and its metabolites in liver and kidney samples involved solvent extraction, Florisil solid-phase-extraction cleanup, and quantitation by GCMS. Recovery experiments for the plasma and tissue samples were conducted over concentration ranges of 10-100 ng mL(-1) and 100-1000 ng mL(-1), respectively. The method was applied to the analysis of trace levels of endosulfan and its metabolites in plasma and tissue samples collected from an animal study. Trace levels of alpha-endosulfan and beta-endosulfan in the ranges of undetectable to 3.11 microg g(-1) and undetectable to 1.19 microg g(-1), respectively, were detected in the kidney samples, whereas trace levels of endosulfan sulfate in the range of 0.02-0.22 microg g(-1) were detected in the liver samples of rats. Neither endosulfan nor its metabolites was detected in any of the plasma samples.
    Matched MeSH terms: Tissue Distribution
  3. Ong LC, Chung FF, Tan YF, Leong CO
    Arch Toxicol, 2016 Jan;90(1):103-18.
    PMID: 25273022 DOI: 10.1007/s00204-014-1376-6
    Carbon nanotubes (CNTs) are an important class of nanomaterials, which have numerous novel properties that make them useful in technology and industry. Generally, there are two types of CNTs: single-walled nanotubes (SWNTs) and multi-walled nanotubes. SWNTs, in particular, possess unique electrical, mechanical, and thermal properties, allowing for a wide range of applications in various fields, including the electronic, computer, aerospace, and biomedical industries. However, the use of SWNTs has come under scrutiny, not only due to their peculiar nanotoxicological profile, but also due to the forecasted increase in SWNT production in the near future. As such, the risk of human exposure is likely to be increased substantially. Yet, our understanding of the toxicological risk of SWNTs in human biology remains limited. This review seeks to examine representative data on the nanotoxicity of SWNTs by first considering how SWNTs are absorbed, distributed, accumulated and excreted in a biological system, and how SWNTs induce organ-specific toxicity in the body. The contradictory findings of numerous studies with regards to the potential hazards of SWNT exposure are discussed in this review. The possible mechanisms and molecular pathways associated with SWNT nanotoxicity in target organs and specific cell types are presented. We hope that this review will stimulate further research into the fundamental aspects of CNTs, especially the biological interactions which arise due to the unique intrinsic characteristics of CNTs.
    Matched MeSH terms: Tissue Distribution
  4. Roselt P, Cullinane C, Noonan W, Elsaidi H, Eu P, Wiebe LI
    Molecules, 2020 Dec 03;25(23).
    PMID: 33287202 DOI: 10.3390/molecules25235700
    Vitamin E, a natural antioxidant, is of interest to scientists, health care pundits and faddists; its nutritional and biomedical attributes may be validated, anecdotal or fantasy. Vitamin E is a mixture of tocopherols (TPs) and tocotrienols (T-3s), each class having four substitutional isomers (α-, β-, γ-, δ-). Vitamin E analogues attain only low concentrations in most tissues, necessitating exacting invasive techniques for analytical research. Quantitative positron emission tomography (PET) with an F-18-labeled molecular probe would expedite access to Vitamin E's biodistributions and pharmacokinetics via non-invasive temporal imaging. (R)-6-(3-[18F]Fluoropropoxy)-2,7,8-trimethyl-2-(4,8,12-trimethyltrideca-3,7,11-trien-1-yl)-chromane ([18F]F-γ-T-3) was prepared for this purpose. [18F]F-γ-T-3 was synthesized from γ-T-3 in two steps: (i) 1,3-di-O-tosylpropane was introduced at C6-O to form TsO-γ-T-3, and (ii) reaction of this tosylate with [18F]fluoride in DMF/K222. Non-radioactive F-γ-T-3 was synthesized by reaction of γ-T-3 with 3-fluoropropyl methanesulfonate. [18F]F-γ-T-3 biodistribution in a murine tumor model was imaged using a small-animal PET scanner. F-γ-T-3 was prepared in 61% chemical yield. [18F]F-γ-T-3 was synthesized in acceptable radiochemical yield (RCY 12%) with high radiochemical purity (>99% RCP) in 45 min. Preliminary F-18 PET images in mice showed upper abdominal accumulation with evidence of renal clearance, only low concentrations in the thorax (lung/heart) and head, and rapid clearance from blood. [18F]F-γ-T-3 shows promise as an F-18 PET tracer for detailed in vivo studies of Vitamin E. The labeling procedure provides acceptable RCY, high RCP and pertinence to all eight Vitamin E analogues.
    Matched MeSH terms: Tissue Distribution/physiology*
  5. Tiede A, Abdul-Karim F, Carcao M, Persson P, Clausen WHO, Kearney S, et al.
    Haemophilia, 2017 Jul;23(4):547-555.
    PMID: 28233381 DOI: 10.1111/hae.13191
    INTRODUCTION: Nonacog beta pegol (N9-GP) is a glycoPEGylated recombinant factor IX (FIX) with an extended half-life developed for routine prophylaxis and the prevention and treatment of bleeding episodes in patients with haemophilia B.

    AIM: The aim of this study was to evaluate the pharmacokinetics (PK) of N9-GP.

    METHODS: Data from 41 previously treated haemophilia B patients, enrolled globally (16 adolescents/adults and 25 children; FIX activity ≤0.02 IU mL-1) with no history of FIX inhibitors, were included. N9-GP was administered once-weekly as 10 IU kg-1or 40 IU kg-1in adolescents/adults and 40 IU kg-1in children. Blood was sampled up to 168 h (1 week) post dose. Standard PK was estimated on the basis of plasma FIX activity vs. time (PK profiles) using non-compartmental methods. Furthermore, a population PK analysis and FIX activity predictions were performed.

    RESULTS: Incremental recoveries were 0.02 (IU mL-1)/(IU kg-1) in both adolescents/adults and children. The extended half-life resulted in mean trough levels of 0.27 IU mL-1for adolescents/adults and 0.17 IU mL-1for children at steady-state after weekly dosing at 40 IU kg-1. The population PK analysis confirmed a mono-exponential decay in FIX activity and allowed for predictions of FIX activity for adolescents/adults above 0.15 IU mL-1at all times and 6.4 days week-1in children.

    CONCLUSION: N9-GP has the potential to shift previously treated haemophilia B patients from a severe/moderate disease state into a mild- or non-haemophilic range for most of the dosing interval, which is expected to reduce the number of bleeding episodes.

    Matched MeSH terms: Tissue Distribution
  6. Tan JSL, Roberts C, Billa N
    J Biomater Sci Polym Ed, 2020 02;31(2):141-154.
    PMID: 31612804 DOI: 10.1080/09205063.2019.1680926
    Oral delivery of amphotericin B (AmpB) is desirable because it provides a more patient-friendly mode of administration compared to the current delivery approach akin with the marketed AmpB formulations. The goal of the study was to investigate the pharmacokinetics and tissue distribution of orally administered chitosan-coated AmpB-loaded nanostructured lipid carriers (ChiAmpB NLC) administered to Sprague Dawley rats at a dose of 15 mg/kg. Orally administered ChiAmpB NLC resulted in a two-fold increase in the area under the curve (AUC0-∞) compared to the uncoated AmpB NLC and marketed Amphotret®. This enhanced bioavailability of AmpB suggests prolonged transit and retention of ChiAmpB NLC within the small intestine through mucoadhesion and subsequent absorption by the lymphatic pathway. The results show that mean absorption and residence times (MAT & MRT) were significantly higher from ChiAmpB NLC compared to the other two formulations, attesting to the mucoadhesive effect. The ChiAmpB NLC presented a lower nephrotic accumulation with preferential deposition in liver and spleen. Thus, the limitations of current marketed IV formulations of AmpB are potentially addressed with the ChiAmpB NLC in addition to utilizing this approach for targeting internal organs in visceral leishmaniasis.
    Matched MeSH terms: Tissue Distribution
  7. Zaborowski MP, Cheah PS, Zhang X, Bushko I, Lee K, Sammarco A, et al.
    Sci Rep, 2019 Nov 22;9(1):17387.
    PMID: 31758005 DOI: 10.1038/s41598-019-53554-y
    Extracellular vesicles (EVs) released by cells play a role in intercellular communication. Reporter and targeting proteins can be modified and exposed on the surface of EVs to investigate their half-life and biodistribution. A characterization of membrane-bound Gaussia luciferase (mbGluc) revealed that its signal was detected also in a form smaller than common EVs (<70 nm). We demonstrated that mbGluc initially exposed on the surface of EVs, likely undergoes proteolytic cleavage and processed fragments of the protein are released into the extracellular space in active form. Based on this observation, we developed a new assay to quantitatively track shedding of membrane proteins from the surface of EVs. We used this assay to show that ectodomain shedding in EVs is continuous and is mediated by specific proteases, e.g. metalloproteinases. Here, we present a novel tool to study membrane protein cleavage and release using both in vitro and in vivo models.
    Matched MeSH terms: Tissue Distribution
  8. Zakarial Ansar FH, Latifah SY, Wan Kamal WHB, Khong KC, Ng Y, Foong JN, et al.
    Int J Nanomedicine, 2020;15:7703-7717.
    PMID: 33116496 DOI: 10.2147/IJN.S262395
    Background: Thymoquinone (TQ), an active compound isolated from Nigella sativa, has been proven to exhibit various biological properties such as antioxidant. Although oral delivery of TQ is valuable, it is limited by poor oral bioavailability and low solubility. Recently, TQ-loaded nanostructured lipid carrier (TQ-NLC) was formulated with the aim of overcoming the limitations. TQ-NLC was successfully synthesized by the high-pressure homogenization method with remarkable physiochemical properties whereby the particle size is less than 100 nm, improved encapsulation efficiency and is stable up to 24 months of storage. Nevertheless, the pharmacokinetics and biodistribution of TQ-NLC have not been studied. This study determined the bioavailability of oral and intravenous administration of thymoquinone-loaded nanostructured lipid carrier (TQ-NLC) in rats and its distribution to organs.

    Materials and Methods: TQ-NLC was radiolabeled with technetium-99m before the administration to the rats. The biodistribution and pharmacokinetics parameters were then evaluated at various time points. The rats were imaged at time intervals and the percentage of the injected dose/gram (%ID/g) in blood and each organ was analyzed.

    Results: Oral administration of TQ-NLC exhibited greater relative bioavailability compared to intravenous administration. It is postulated that the movement of TQ-NLC through the intestinal lymphatic system bypasses the first metabolism and therefore enhances the relative bioavailability. However, oral administration has a slower absorption rate compared to intravenous administration where the AUC0-∞ was 4.539 times lower than the latter.

    Conclusion: TQ-NLC had better absorption when administered intravenously compared to oral administration. However, oral administration showed greater bioavailability compared to the intravenous route. This study provides the pharmacokinetics and biodistribution profile of TQ-NLC in vivo which is useful to assist researchers in clinical use.

    Matched MeSH terms: Tissue Distribution
  9. Ruman U, Fakurazi S, Masarudin MJ, Hussein MZ
    Int J Nanomedicine, 2020;15:1437-1456.
    PMID: 32184597 DOI: 10.2147/IJN.S236927
    The development of therapeutics and theranostic nanodrug delivery systems have posed a challenging task for the current researchers due to the requirement of having various nanocarriers and active agents for better therapy, imaging, and controlled release of drugs efficiently in one platform. The conventional liver cancer chemotherapy has many negative effects such as multiple drug resistance (MDR), high clearance rate, severe side effects, unwanted drug distribution to the specific site of liver cancer and low concentration of drug that finally reaches liver cancer cells. Therefore, it is necessary to develop novel strategies and novel nanocarriers that will carry the drug molecules specific to the affected cancerous hepatocytes in an adequate amount and duration within the therapeutic window. Therapeutics and theranostic systems have advantages over conventional chemotherapy due to the high efficacy of drug loading or drug encapsulation efficiency, high cellular uptake, high drug release, and minimum side effects. These nanocarriers possess high drug accumulation in the tumor area while minimizing toxic effects on healthy tissues. This review focuses on the current research on nanocarrier-based therapeutics and theranostic drug delivery systems excluding the negative consequences of nanotechnology in the field of drug delivery systems. However, clinical developments of theranostics nanocarriers for liver cancer are considered outside of the scope of this article. This review discusses only the recent developments of nanocarrier-based drug delivery systems for liver cancer therapy and diagnosis. The negative consequences of individual nanocarrier in the drug delivery system will also not be covered in this review.
    Matched MeSH terms: Tissue Distribution
  10. Ashhar Z, Yusof NA, Ahmad Saad FF, Mohd Nor SM, Mohammad F, Bahrin Wan Kamal WH, et al.
    Molecules, 2020 Jun 09;25(11).
    PMID: 32526838 DOI: 10.3390/molecules25112668
    Early diagnosis of bone metastases is crucial to prevent skeletal-related events, and for that, the non-invasive techniques to diagnose bone metastases that make use of image-guided radiopharmaceuticals are being employed as an alternative to traditional biopsies. Hence, in the present work, we tested the efficacy of a gallium-68 (68Ga)-based compound as a radiopharmaceutical agent towards the bone imaging in positron emitting tomography (PET). For that, we prepared, thoroughly characterized, and radiolabeled [68Ga]Ga-NODAGA-pamidronic acid radiopharmaceutical, a 68Ga precursor for PET bone cancer imaging applications. The preparation of NODAGA-pamidronic acid was performed via the N-Hydroxysuccinimide (NHS) ester strategy and was characterized using liquid chromatography-mass spectrometry (LC-MS) and tandem mass spectrometry (MSn). The unreacted NODAGA chelator was separated using the ion-suppression reverse phase-high performance liquid chromatography (RP-HPLC) method, and the freeze-dried NODAGA-pamidronic acid was radiolabeled with 68Ga. The radiolabeling condition was found to be most optimum at a pH ranging from 4 to 4.5 and a temperature of above 60 °C. From previous work, we found that the pamidronic acid itself has a good bone binding affinity. Moreover, from the analysis of the results, the ionic structure of radiolabeled [68Ga]Ga-NODAGA-pamidronic acid has the ability to improve the blood clearance and may exert good renal excretion, enhance the bone-to-background ratio, and consequently the final image quality. This was reflected by both the in vitro bone binding assay and in vivo animal biodistribution presented in this research.
    Matched MeSH terms: Tissue Distribution
  11. Yap CK, Ismail A, Tan SG
    Environ Int, 2003 Jul;29(4):521-8.
    PMID: 12705949
    Concentrations of cadmium (Cd), lead (Pb) and zinc (Zn) in total soft tissues (ST) and byssus (BYS) of the green-lipped mussel Perna viridis from 11 different geographical locations off the west coast of Peninsular Malaysia were determined. The metal concentrations distributed between the BYS and ST were compared. The results of this study indicated that higher levels of Cd (1.31 microg/g), Pb (38.49 microg/g) and Zn (206.52 microg/g) were accumulated in the BYS than in the total ST (Cd: 0.29 microg/g; Pb: 8.27 microg/g; Zn: 102.6 microg/g). Semi-static and short period controlled laboratory experiments were also conducted for the accumulation and depuration of Cd, Pb and Zn in the total ST and BYS of P. viridis. The ratios (BYS/ST) for Pb and Cd from the laboratory experiments showed that the total ST accumulated more metals than the BYS. Therefore, these laboratory results disagreed with those found for the field samples. However, the laboratory results for the Zn ratio (BYS/ST) agreed with those of the field samples. It was evident that when compared to the ST, the BYS was a more sensitive biomonitoring organ for Zn while it could be a complementary organ for Cd and Pb in the total ST. Since total ST of P. viridis had been reported to have regulative mechanism for Zn, its BYS can be used as a biomonitoring organ for the identification of coastal areas exposed to Zn pollution.
    Matched MeSH terms: Tissue Distribution
  12. Yap CK, Ismail A, Tan SG, Omar H
    Environ Int, 2002 Apr;28(1-2):117-26.
    PMID: 12046948
    Total concentrations and speciation of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in surface sediment samples were correlated with the respective metal measured in the total soft tissue of the green-lipped mussel Perna viridis, collected from water off the west coast of Peninsular Malaysia. The aim of this study is to relate the possible differences in the accumulation patterns of the heavy metals in P. viridis to those in the surface sediment. The sequential extraction technique was employed to fractionate the sediment into 'freely leachable and exchangeable' (EFLE), 'acid-reducible,' 'oxidisable-organic' and 'resistant' fractions. The results showed that significant (P .05) was found between Zn in P viridis and all the sediment geochemical fractions of Zn and total Zn in the sediment. This indicated that Zn was possibly regulated from the soft tissue of P. viridis. The present results supported the use of P viridis as a suitable biomonitoring agent for Cd, Cu and Pb.
    Matched MeSH terms: Tissue Distribution
  13. Moshikur RM, Ali MK, Wakabayashi R, Moniruzzaman M, Goto M
    Mol Pharm, 2021 08 02;18(8):3108-3115.
    PMID: 34250805 DOI: 10.1021/acs.molpharmaceut.1c00324
    Coronavirus disease 2019 (COVID-19) has spread across the world, and no specific antiviral drugs have yet been approved to combat this disease. Favipiravir (FAV) is an antiviral drug that is currently in clinical trials for use against COVID-19. However, the delivery of FAV is challenging because of its limited solubility, and its formulation is difficult with common organic solvents and water. To address these issues, four FAV ionic liquids (FAV-ILs) were synthesized as potent antiviral prodrugs and were fully characterized by nuclear magnetic resonance (NMR) spectroscopy, Fourier-transform infrared (FT-IR) spectrometry, powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG), and differential scanning calorimetry (DSC). The aqueous solubility and in vivo pharmacokinetic properties of the FAV-ILs were also evaluated. The FAV-ILs exhibited improved aqueous solubility by 78 to 125 orders of magnitude when compared with that of free FAV. Upon oral dosing in mice, the absolute bioavailability of the β-alanine ethyl ester FAV formulation was increased 1.9-fold compared with that of the control FAV formulation. The peak blood concentration, elimination half-life, and mean absorption time of FAV were also increased by 1.5-, 2.0-, and 1.5-fold, respectively, compared with the control. Furthermore, the FAV in the FAV-ILs exhibited significantly different biodistribution compared with the control FAV formulation. Interestingly, drug accumulation in the lungs and liver was improved 1.5-fold and 1.3-fold, respectively, compared with the control FAV formulation. These results indicate that the use of ILs exhibits potential as a simple, scalable strategy to improve the solubility and oral absorption of hydrophobic drugs, such as FAV.
    Matched MeSH terms: Tissue Distribution
  14. Nograles N, Abdullah S, Shamsudin MN, Billa N, Rosli R
    J Biosci Bioeng, 2012 Feb;113(2):133-40.
    PMID: 22093752 DOI: 10.1016/j.jbiosc.2011.10.003
    Alginate, a natural polysaccharide, was explored in this study as an oral delivery vehicle of a mammalian expression vector into the murine intestinal mucosa. Alginate microspheres were produced through water-in-oil (W/O) emulsification method. Average diameter sizes of microspheres were 46.88 μm±3.07 μm with significant size reduction upon utilization of 1.0% Span80. Plasmid DNA (pDNA) carrying green fluorescent protein reporter gene (GFP), pVAX-GFP, was encapsulated within microspheres at efficiencies of 72.9 to 74.4%, carrying maximum load of 6 μg pDNA. Alginate microspheres demonstrated shrinkage in pH 1.2 and swelling in pH 9.0 with pDNA release about twice the amount released in acidic environment. Oral delivery of pVAX-GFP loaded-microspheres, at 50 μg, 100 μg and 150 μg dose, was performed on BALB/c mice. Tissue biodistribution, investigated through flow cytometric analysis, demonstrated GFP positive intestinal cells (<1.0%) with 1.3-fold higher levels for the 100 μg dose; therefore suggesting feasibility of the approach for oral gene delivery and vaccination.
    Matched MeSH terms: Tissue Distribution
  15. Wong TW
    J Control Release, 2014 Nov 10;193:257-69.
    PMID: 24801250 DOI: 10.1016/j.jconrel.2014.04.045
    Transdermal drug delivery is hindered by the barrier property of the stratum corneum. It limits the route to transport of drugs with a log octanol-water partition coefficient of 1 to 3, molecular weight of less than 500Da and melting point of less than 200°C. Active methods such as iontophoresis, electroporation, sonophoresis, magnetophoresis and laser techniques have been investigated for the past decades on their ability, mechanisms and limitations in modifying the skin microenvironment to promote drug diffusion and partition. Microwave, an electromagnetic wave characterized by frequencies range between 300MHz and 300GHz, has recently been reported as the potential skin permeation enhancer. Microwave has received a widespread application in food, engineering and medical sectors. Its potential use to facilitate transdermal drug transport is still in its infancy stage of evaluation. This review provides an overview and update on active methods utilizing electrical, magnetic, photomechanical and cavitational waves to overcome the skin barrier for transdermal drug administration with insights into mechanisms and future perspectives of the latest microwave technique described.
    Matched MeSH terms: Tissue Distribution
  16. Leow SS, Sekaran SD, Sundram K, Tan Y, Sambanthamurthi R
    J Nutrigenet Nutrigenomics, 2013;6(6):305-26.
    PMID: 24642698 DOI: 10.1159/000357948
    Plant phenolics can inhibit, retard or reverse carcinogenesis, and may thus help prevent or treat cancer. Oil palm phenolics (OPP) previously showed anti-tumour activities in vivo via a cytostatic mechanism at 1,500 ppm gallic acid equivalent. Here, we report other possible molecular mechanisms by which this extract attenuates cancer, especially those concerning the immune response.
    Matched MeSH terms: Tissue Distribution
  17. Saravanan M, Bhaskar K, Maharajan G, Pillai KS
    J Drug Target, 2011 Feb;19(2):96-103.
    PMID: 20380621 DOI: 10.3109/10611861003733979
    We have previously reported on the targeting of diclofenac sodium in joint inflammation using gelatin magnetic microspheres. To overcome complications in the administration of magnetic microspheres and achieve higher targeting efficiency, the present work focuses on the formulation of gelatin microspheres for intra-articular administration. Drug-loaded microspheres were prepared by the emulsification/cross-linking method, characterized by drug loading, size distribution, scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), gas chromatography, and in vitro release studies. The targeting efficiency of microspheres was studied in vivo in rabbits. The microspheres showed drug loading of 9.8, 18.3, and 26.7% w/w with an average size range of 37-46 µm, depending upon the drug-polymer ratio. They were spherical in nature and free from surface drug as evidenced by the SEM photographs. FT-IR, DSC, and XRD revealed the absence of drug-polymer interaction and amorphous nature of entrapped drug. Gas chromatography confirms the absences of residual glutaraldehyde. The formulated microspheres could prolong the drug release up to 30 days in vitro. About 81.2 and 43.7% of administered drug in the microspheres were recovered from the target joint after 1 and 7 days of postintra-articular injection, respectively, revealing good targeting efficiency.
    Matched MeSH terms: Tissue Distribution
  18. Teoh M, Narayanan P, Moo KS, Radhakrisman S, Pillappan R, Bukhari NI, et al.
    Pak J Pharm Sci, 2010 Jan;23(1):35-41.
    PMID: 20067864
    Imatinib inhibits Bcr-Abl, c-KIT and PDGFR kinases. It is approved for the treatment of chronic myeloid leukemia (CML), gastrointestinal stromal tumors (GIST) and has further therapeutic potential. Male ICR mice were given imatinib PO (50 or 25 mg/kg, 5 doses every 2 h); euthanized 2 h after the last dose administration; plasma, liver, brain, spleen and kidney were collected and imatinib concentration measured by an optimized HPLC method for quantification in tissues. Methanol (1:1 v/v plasma) and pH 4, 40:30:30 (v/v/v) water-methanol-acetonitrile at 5 ml/g (brain) and 10 ml/g (spleen, kidney, liver) ratio was added to the samples, homogenized, sonicated, centrifuged (15,000 rpm, 5 min, 2 degrees C) and the supernatant injected into an Inertsil CN-3 column (4.6 mm x 150 mm, 5 microm) using 64:35:1 (v/v/v) water-methanol-triethylamine (pH 4.8), flow rate 1 ml/min, 25 degrees C. Imatinib eluted at 7.5 min (268 nm). Linearity: 0.1-50 microg/ml; precision, accuracy, inter- and intra-day variability was within 15%. Recovery was above 95% (plasma), 80% (brain) and 90% (kidney, liver, spleen). Imatinib tissue concentrations were 6-8 folds higher than plasma except brain, where the ratio decreased from 0.24 to 0.08 suggesting limited brain penetration, likely due to blood brain barrier efflux transporters. The extensive distribution supports the expansion of therapeutic applications.
    Matched MeSH terms: Tissue Distribution
  19. Yap CK, Noorhaidah A, Azlan A, Nor Azwady AA, Ismail A, Ismail AR, et al.
    Ecotoxicol Environ Saf, 2009 Feb;72(2):496-506.
    PMID: 18243309 DOI: 10.1016/j.ecoenv.2007.12.005
    The distributions of Cu, Zn, and Pb concentrations in the selected soft tissues (foot, cephalic tentacle, mantle, muscle, gill, digestive caecum, and remaining soft tissues) and shells of the mud-flat snail Telescopium telescopium were determined in snails from eight geographical sites in the south-western intertidal area of Peninsular Malaysia. Generally, the digestive caecum compared with other selected soft tissues, accumulated higher concentration of Zn (214.35+/-14.56 microg/g dry weight), indicating that the digestive caecum has higher affinity for the essential Zn to bind to metallothionein. The shell demonstrated higher concentrations of Pb (41.23+/-1.20 microg/g dry weight) when compared to the selected soft tissues except gill from Kuala Sg. Ayam (95.76+/-5.32 microg/g dry weight). The use of different soft tissues also can solve the problem of defecation to reduce error in interpreting the bioavailability of heavy metals in the intertidal area.
    Matched MeSH terms: Tissue Distribution
  20. Charoo NA, Shamsher AA, Lian LY, Abrahamsson B, Cristofoletti R, Groot DW, et al.
    J Pharm Sci, 2014 Feb;103(2):378-91.
    PMID: 24382794 DOI: 10.1002/jps.23817
    Literature data relevant to the decision to allow a waiver of in vivo bioequivalence (BE) testing for the approval of immediate-release (IR) solid oral dosage forms containing bisoprolol as the sole active pharmaceutical ingredient (API) are reviewed. Bisoprolol is classified as a Class I API according to the current Biopharmaceutics Classification System (BCS). In addition to the BCS class, its therapeutic index, pharmacokinetic properties, data related to the possibility of excipient interactions, and reported BE/bioavailability problems are taken into consideration. Qualitative compositions of IR tablet dosage forms of bisoprolol with a marketing authorization (MA) in ICH (International Conference on Harmonisation) countries are tabulated. It was inferred that these tablets had been demonstrated to be bioequivalent to the innovator product. No reports of failure to meet BE standards have been made in the open literature. On the basis of all these pieces of evidence, a biowaiver can currently be recommended for bisoprolol fumarate IR dosage forms if (1) the test product contains only excipients that are well known, and used in normal amounts, for example, those tabulated for products with MA in ICH countries and (2) both the test and comparator dosage form are very rapidly dissolving, or, rapidly dissolving with similarity of the dissolution profiles demonstrated at pH 1.2, 4.5, and 6.8.
    Matched MeSH terms: Tissue Distribution
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