Displaying publications 1 - 20 of 431 in total

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  1. Mansor SM, Navaratnam V, Mohamad M, Hussein S, Kumar A, Jamaludin A, et al.
    Br J Clin Pharmacol, 1989 Mar;27(3):381-6.
    PMID: 2785812
    A single dose pharmacokinetic study of a combined antimalarial formulation of mefloquine, sulphadoxine and pyrimethamine (Fansimef) has been performed in 10 healthy adult male Malaysian volunteers. The dose consisted of two tablets containing 250 mg mefloquine base, 500 mg sulphadoxine base and 25 mg pyrimethamine base each. Plasma concentrations of mefloquine and pyrimethamine were measured by GC-ECD, those of sulphadoxine by h.p.l.c. Time to peak concentrations (mean +/- s.d. for mefloquine (5.70 +/- 0.95 h), sulphadoxine (3.75 +/- 2.03 h) and pyrimethamine (3.30 +/- 1.98 h) were similar to those observed by others after administration of the single compounds. This was also true for elimination half-lives (t1/2). The t1/2s for mefloquine, sulphadoxine and pyrimethamine were 387 +/- 98 h, 255 +/- 61 h and 114 +/- 42 h, respectively.
    Matched MeSH terms: Pyrimethamine/pharmacokinetics*; Quinolines/pharmacokinetics*; Sulfadoxine/pharmacokinetics*; Sulfanilamides/pharmacokinetics*
  2. Gorajana A, Kit WW, Dua K
    Recent Pat Drug Deliv Formul, 2015;9(2):167-82.
    PMID: 25714525
    OBJECTIVE: Norfloxacin has a low aqueous solubility which leads to poor dissolution. Keeping this fact in mind the purpose of the present study is to formulate and evaluate norfloxacin solid dispersion.

    METHODS: Solid dispersions were prepared using hydrophilic carriers like polyethylene glycol (PEG) 4000, polyvinylpyrrolidone (PVP) k30 and carbopol 974pNF (CP) in various ratios using solvent evaporation technique. These formulations were evaluated using solubility studies, dissolution studies; Fourier transmitted infrared spectroscopy (FTIR), X-ray diffraction (XRD), and differential scanning calorimetery (DSC). The influence of polymer type and drug to polymer ratio on the solubility and dissolution rate of norfloxacin was also evaluated.

    RESULTS: FTIR analysis showed no interaction of all three polymers with norfloxacin. The results from XRD and DSC analyses of the solid dispersion preparations showed that norfloxacin existsin its amorphous form. Among the Norfloxacin: PEG solid dispersions, Norfloxacin: PEG 1:14 ratio showed the highest dissolution rate at pH 6.8. For norfloxacin: PVP solid dispersions, norfloxacin: PVP 1:10 ratio showed the highest dissolution rate at pH 6.8. For Norfloxacin: CP solid dispersions, norfloxacin: P 1:2 ratio showed the highest dissolution rate at pH 6.8.

    CONCLUSION: The solid dispersion of norfloxacin with polyethylene glycol (PEG) 4000, polyvinylpyrrolidone (PVP) k30 and carbopol 974p NF (CP), lends an ample credence for better therapeutic efficacy.

    Matched MeSH terms: Acrylates/pharmacokinetics; Norfloxacin/pharmacokinetics; Polyethylene Glycols/pharmacokinetics; Povidone/pharmacokinetics
  3. Lim PE, Lee CK, Din Z
    Sci. Total Environ., 1998 May 14;216(1-2):147-57.
    PMID: 9618930
    A study on the kinetics of accumulation and depuration of Zn, Cu, Pb and Cd by the oysters (Crassostrea iredalei and Crassostrea belcheri) cultured at two locations in the Merbok Estuary, Malaysia was conducted. A first-order kinetic model was employed to fit the experimental data in order to estimate the rate constants for uptake and elimination processes and to predict the bioconcentration factors (BCF). Among the four metals studied, only the Zn accumulation process could not be modelled using first-order kinetics. The elimination rate constants estimated from depuration data for C. iredalei are found to be much greater than those from accumulation data. The results suggest that the values of kinetic parameters and BCFs derived under conditions of both aqueous and dietary exposure are probably more site- than species-specific.
    Matched MeSH terms: Cadmium/pharmacokinetics; Copper/pharmacokinetics; Lead/pharmacokinetics; Water Pollutants, Chemical/pharmacokinetics*; Zinc/pharmacokinetics; Metals, Heavy/pharmacokinetics*
  4. Hamid O, Tajuddin AA
    J Ocul Pharmacol Ther, 2000 Dec;16(6):565-9.
    PMID: 11132903
    The kinetics of topical triamterene penetration were estimated from the time-course measurements of triamterene (in Dyazide) concentrations in the anterior chamber of six rabbits (n=12, left and right eyes). The two-compartment model of Jones and Maurice (1) was fitted to the measurements. We found the apparent elimination rate constant oftriamterene A = 0.33 +/- 0.12 hr(-1), the apparent absorption rate constant of triamterene B = 2.68 +/- 0.55 hr(-1), the cornea-aqueous transfer coefficient in reference to the corneal volume of triamterene kc.ca = 0.28 +/- 0.05 hr(-1), the loss coefficient of triamterene from the anterior chamber ko = 0.43 +/- 0.16 hr(-1) and the amount of triamterene in the cornea at time zero Mo = 483 +/- 125 ng/ml. The mean of ko = 0.43 hr(-1) is significantly lower (p = 0.04% using ZTEST) than the lower limit of aqueous loss coefficient = 0.58 hr(-1) usually found in rabbits (2). We conclude that Dyazide lowers the aqueous flow rate in the positive direction, considering glaucoma treatment. Peak triamterene concentration in the anterior chamber was P = 120 +/- 32 ng/ml. Half-life for elimination from the aqueous humor was T1/2 = 1.84 +/- 0.65 hr (Mean +/- SD).
    Matched MeSH terms: Diuretics/pharmacokinetics*; Triamterene/pharmacokinetics*
  5. Jayaraman SD, Ismail S, Nair NK, Navaratnam V
    J. Chromatogr. B Biomed. Sci. Appl., 1997 Mar 07;690(1-2):253-7.
    PMID: 9106050
    A method is described for the determination of pyronaridine in plasma using high-performance liquid chromatography with fluorescence detection. The method involves liquid-liquid extraction with phosphate buffer (pH 6.0, 0.05 M) and diethyl ether-hexane (70:30%, v/v) and chromatographic separation on a C18 column (Nucleosil, 250 x 4.6 mm I.D., 5 microns particle size) with acetonitrile-0.05 M phosphate buffer pH 6.0 (60:40%, v/v) as the mobile phase (1 ml/min) and detection by fluorescence (lambda ex = 267 nm, lambda em = 443 nm). The detector response is linear up to 1000 ng and the overall recoveries of pyronaridine and quinine were 90.0 and 60.3%, respectively. The assay procedure was adequately sensitive to measure 10 ng/ml pyronaridine in plasma samples with acceptable precision (< 15% C.V.). The method was found to be suitable for use in clinical pharmacological studies.
    Matched MeSH terms: Antimalarials/pharmacokinetics; Naphthyridines/pharmacokinetics
  6. Liew KB, Peh KK, Loh GO, Tan YT
    Drug Dev Ind Pharm, 2014 Sep;40(9):1156-62.
    PMID: 23688276 DOI: 10.3109/03639045.2013.798805
    Although the general pharmacokinetics of cephalexin is quite established up-to-date, however, no population-based study on Cephalexin pharmacokinetics profile in Malay population has been reported yet in the literature.
    Matched MeSH terms: Capsules/pharmacokinetics; Cephalexin/pharmacokinetics*; Tablets/pharmacokinetics
  7. Heng LY, Jusoh K, Ling CH, Idris M
    Bull Environ Contam Toxicol, 2004 Feb;72(2):373-9.
    PMID: 15106775
    Matched MeSH terms: Cadmium/pharmacokinetics; Lead/pharmacokinetics; Water Pollutants/pharmacokinetics
  8. Lang CC, Jamal SK, Mohamed Z, Mustafa MR, Mustafa AM, Lee TC
    Br J Clin Pharmacol, 2003 Jun;55(6):588-90.
    PMID: 12814453
    AIMS: Nafcillin (Wyeth Laboratories, Philadelphia, PA, USA) has been reported to induce the metabolism of cyclosporin and warfarin, which are known substrates of cytochrome P-450 (CYP). However, there has not been any report to date on its possible interaction with nifedipine, an index substrate of the enzyme, CYP3A4.

    METHODS: Nine healthy normotensive subjects participated in this randomized placebo-controlled two-way crossover study examining the effects of 5 days' pretreatment of nafcillin 500 mg or placebo four times daily on the pharmacokinetics of an oral dose of nifedipine 10 mg. Plasma nifedipine concentrations were measured by gas chromatography-mass spectro.

    RESULTS: The area under the plasma nifedipine concentration-time curve (AUC0-alpha) in nafcillin-pretreated subjects (80.9 +/- 32.9 micro g l-1 h-1) was significantly decreased compared with subjects who received only nifedipine (216.4 +/- 93.2 micro g l-1 h-1) (P < 0.001). Total plasma clearance of nifedipine (CL/F) was significantly increased with nafcillin pretreatment (138.5 +/- 42.0 l h-1 vs 56.5 +/- 32.0 l h-1) (P < 0.002).

    CONCLUSIONS: The results show that nafcillin pretreatment markedly increased the clearance of nifedipine and suggest that nafcillin is a potent inducer of CYP enzyme.

    Matched MeSH terms: Nafcillin/pharmacokinetics*; Nifedipine/pharmacokinetics*; Penicillins/pharmacokinetics*
  9. Doi SA
    Clin. Pharmacol. Ther., 1994 May;55(5):597-601.
    PMID: 8181204
    Pharmacokinetic-pharmacodynamic information regarding warfarin is used to produce a predictive model based on the idea that pharmacodynamic variability is more important than pharmacokinetic variability in the overall dose-response variability to warfarin. A modification of the maximum effect model is tested on a group of patients initiating oral anticoagulation with warfarin. Results indicate that the model can account for at least half of the total variation in maintenance doses observed (sample coefficient of determination, 0.53) and offer the physician a framework for dose requirements at the onset of therapy. The basic prediction equation is as follows: Maintenance dose = (11/international normalized ratio)-1, with a coefficient of correlation of 0.73 (95% confidence limits, 0.46-0.88). Application of this model may improve on the traditional empiric approach to warfarin dose adjustment.
    Matched MeSH terms: Warfarin/pharmacokinetics
  10. 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: Cadmium/pharmacokinetics; Copper/pharmacokinetics; Lead/pharmacokinetics; Water Pollutants, Chemical/pharmacokinetics; Zinc/pharmacokinetics; Metals, Heavy/pharmacokinetics
  11. Zulfadhly Z, Mashitah MD, Bhatia S
    Environ. Pollut., 2001;112(3):463-70.
    PMID: 11291452
    The ability of Pycnoporus sanguineus to adsorb heavy metals from aqueous solution was investigated in fixed-bed column studies. The experiments were conducted to study the effect of important design parameters such as column bed height, flow rate and initial concentration of solution. The breakthrough profiles were obtained in these studies. A mathematical model based on external mass transfer and pore diffusion was used for the prediction of mass transfer coefficient and effective diffusivity of metals in macro-fungi bed. Experimental breakthrough profiles were compared with the simulated breakthrough profiles obtained from the mathematical model. Bed Depth Service Time (BDST) model was used to analyse the experimental data and evaluated the performance of biosorption column. The BDST model parameters needed for the design of biosorption columns were evaluated for lead, copper and cadmium removal in the column. The columns were regenerated by eluting the metal ions using 0.1 M hydrochloric acid solution after the adsorption studies. The columns were subjected to repeated cycles of adsorption of same metal ions and desorption to evaluate the removal efficiency after adsorption-desorption.
    Matched MeSH terms: Cadmium/pharmacokinetics; Copper/pharmacokinetics; Lead/pharmacokinetics; Metals, Heavy/pharmacokinetics*
  12. Yap MK, Tan NH, Sim SM, Fung SY, Tan CH
    PLoS Negl Trop Dis, 2014 Jun;8(6):e2890.
    PMID: 24901441 DOI: 10.1371/journal.pntd.0002890
    BACKGROUND: The optimization of snakebite management and the use of antivenom depend greatly on the knowledge of the venom's composition as well as its pharmacokinetics. To date, however, pharmacokinetic reports on cobra venoms and their toxins are still relatively limited. In the present study, we investigated the pharmacokinetics of Naja sumatrana (Equatorial spitting cobra) venom and its major toxins (phospholipase A2, neurotoxin and cardiotoxin), following intravenous and intramuscular administration into rabbits.

    PRINCIPAL FINDINGS: The serum antigen concentration-time profile of the N. sumatrana venom and its major toxins injected intravenously fitted a two-compartment model of pharmacokinetics. The systemic clearance (91.3 ml/h), terminal phase half-life (13.6 h) and systemic bioavailability (41.9%) of N. sumatrana venom injected intramuscularly were similar to those of N. sputatrix venom determined in an earlier study. The venom neurotoxin and cardiotoxin reached their peak concentrations within 30 min following intramuscular injection, relatively faster than the phospholipase A2 and whole venom (Tmax=2 h and 1 h, respectively). Rapid absorption of the neurotoxin and cardiotoxin from the injection site into systemic circulation indicates fast onsets of action of these principal toxins that are responsible for the early systemic manifestation of envenoming. The more prominent role of the neurotoxin in N. sumatrana systemic envenoming is further supported by its significantly higher intramuscular bioavailability (Fi.m.=81.5%) compared to that of the phospholipase A2 (Fi.m.=68.6%) or cardiotoxin (Fi.m.=45.6%). The incomplete absorption of the phospholipase A2 and cardiotoxin may infer the toxins' affinities for tissues at the injection site and their pathological roles in local tissue damages through synergistic interactions.

    CONCLUSION/SIGNIFICANCE: Our results suggest that the venom neurotoxin is absorbed very rapidly and has the highest bioavailability following intramuscular injection, supporting its role as the principal toxin in systemic envenoming.

    Matched MeSH terms: Cobra Neurotoxin Proteins/pharmacokinetics*; Cobra Venoms/pharmacokinetics*; Phospholipases A2/pharmacokinetics*; Cardiotoxins/pharmacokinetics*
  13. Reddy AV, Jaafar J, Aris AB, Majid ZA, Umar K, Talib J, et al.
    J Sep Sci, 2015 Aug;38(15):2580-7.
    PMID: 25989063 DOI: 10.1002/jssc.201500250
    A sensitive ultra high performance liquid chromatography with tandem mass spectrometry method was developed for the simultaneous determination of darunavir, ritonavir and tenofovir in human plasma. Sample preparation involved a simple liquid-liquid extraction using 200 μL of human plasma extracted with methyl tert-butyl ether for three analytes and internal standard. The separation was accomplished on an Acquity UPLC BEH C18 (50 mm x 2.1 mm, 1.7 μm) analytical column using gradient elution of acetonitrile/methanol (80:20, v/v) and 5.0 mM ammonium acetate containing 0.01% formic acid at a flow rate of 0.4 mL/min. The linearity of the method ranged between 20.0 and 12 000 ng/mL for darunavir, 2.0 and 2280 ng/mL for ritonavir, and 14.0 and 1600 ng/mL for tenofovir using 200 μL of plasma. The method was completely validated for its selectivity, sensitivity, linearity, precision and accuracy, recovery, matrix effect, stability, and dilution integrity. The extraction recoveries were consistent and ranged between 79.91 and 90.04% for all three analytes and internal standard. The method exhibited good intra-day and inter-day precision between 1.78 and 6.27%. Finally the method was successfully applied for human pharmacokinetic study in eight healthy male volunteers after the oral administration of 600 mg darunavir along with 100 mg ritonavir and 100 mg tenofovir as boosters.
    Matched MeSH terms: Tenofovir/pharmacokinetics; Darunavir/pharmacokinetics; HIV Protease Inhibitors/pharmacokinetics; Ritonavir/pharmacokinetics
  14. Yusof SR, Abbott NJ, Avdeef A
    Eur J Pharm Sci, 2017 Aug 30;106:274-286.
    PMID: 28614733 DOI: 10.1016/j.ejps.2017.06.016
    Most studies of blood-brain barrier (BBB) permeability and transport are conducted at a single pH, but more detailed information can be revealed by using multiple pH values. A pH-dependent biophysical model was applied to the mechanistic analysis of published pH-dependent BBB luminal uptake data from three opioid derivatives in rat: pentazocine (Suzuki et al., 2002a, 2002b), naloxone (Suzuki et al., 2010a), and oxycodone (Okura et al., 2008). Two types of data were processed: in situ brain perfusion (ISBP) and brain uptake index (BUI). The published perfusion data were converted to apparent luminal permeability values, Papp, and analyzed by the pCEL-X program (Yusof et al., 2014), using the pH-dependent Crone-Renkin equation (pH-CRE) to determine the impact of cerebrovascular flow on the Michaelis-Menten transport parameters (Avdeef and Sun, 2011). For oxycodone, the ISBP data had been measured at pH7.4 and 8.4. The present analysis indicates a 7-fold lower value of the cerebrovascular flow velocity, Fpf, than that expected in the original study. From the pyrilamine-inhibited data, the flow-corrected passive intrinsic permeability value was determined to be P0=398×10-6cm·s-1. The uptake data indicate that the neutral form of oxycodone is affected by a transporter at pH8.4. The extent of the cation uptake was less certain from the available data. For pentazocine, the brain uptake by the BUI method had been measured at pH5.5, 6.5, and 7.4, in a concentration range 0.1-40mM. Under similar conditions, ISBP data were also available. The pH-CRE determined values of Fpf from both methods were nearly the same, and were smaller than the expected value in the original publication. The transport of the cationic pentazocine was not fully saturated at pH5.5 at 40mM. The transport of the neutral species at pH7.4 appeared to reach saturation at 40mM pentazocine concentration, but not at 12mM. In the case of naloxone, a pH-dependent Michaelis-Menten equation (pH-MME) analysis of the data indicated a smooth sigmoidal transition from a higher capacity uptake process affecting cationic naloxone (pH5.0-7.0) to a lower capacity uptake process affecting the neutral drug (pH8.0-8.5), with cross-over point near pH7.4. Evidently, measurements at multiple pH values can reveal important information about both cerebrovascular flow and BBB transport kinetics.
    Matched MeSH terms: Analgesics, Opioid/pharmacokinetics*; Naloxone/pharmacokinetics*; Oxycodone/pharmacokinetics*; Pentazocine/pharmacokinetics*
  15. Tassaneeyakul W, Kumar S, Gaysonsiri D, Kaewkamson T, Khuroo A, Tangsucharit P, et al.
    Int J Clin Pharmacol Ther, 2010 Sep;48(9):614-20.
    PMID: 20860915
    OBJECTIVES: To compare the bioavailability of two risperidone orodispersible tablet products, Risperidone 1 mg Mouth dissolving tablet, Ranbaxy (Malaysia) Sdn. Bhd., Malaysia, as a test product and Risperdal 1 mg Quicklet, Janssen Ortho LLC, Gurabo, Puerto Rico, as a reference product, in healthy male volunteers under fasting condition.

    MATERIALS AND METHODS: A randomized, 2-treatment, 2-period, 2-sequence, single dose, crossover with a washout period of 2 weeks, was conducted in 24 healthy Thai male volunteers. Blood samples were collected at 0, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 10, 12, 24, 36, 48, 72 and 96 h following drug administration. Plasma concentrations of risperidone and 9-hydroxyrisperidone were determined using a validated LC-MS-MS method. The pharmacokinetic parameters of risperidone and 9-hydroxyrisperidone were determined using a non-compartmental model.

    RESULTS: The geometric means ratios (%) and 90% confidence interval (CI) of the test and reference products for the log-transformed pharmacokinetic parameters, Cmax, AUC0-t and AUC0-inf of risperidone were 104.49 % (92.79% - 117.66%), 100.96 % (92.15% - 110.61 %) and 97.99 % (90.72% - 105.85%). The 90% CI of geometric means ratios of the test and reference products for the log-transformed pharmacokinetic parameters, Cmax, AUC0-t and AUC0-inf of 9-hydroxyrisperidone were 97.00%, 96.97% and 97.49%.

    CONCLUSIONS: The 90% CI for the geometric means ratios (test/reference) of the log-trasformed Cmax, AUC0-t and AUC0-inf of risperidone and its major active metabolite were within the bioequivalence acceptance criteria of 80% - 125% of the US-FDA.

    Matched MeSH terms: Antipsychotic Agents/pharmacokinetics*; Risperidone/pharmacokinetics*
  16. Khan KM, Naz F, Taha M, Khan A, Perveen S, Choudhary MI, et al.
    Eur J Med Chem, 2014 Mar 3;74:314-23.
    PMID: 24486414 DOI: 10.1016/j.ejmech.2014.01.001
    Thiourea derivatives (1-38) were synthesized and evaluated for their urease inhibition potential. The synthetic compounds showed a varying degree of in vitro urease inhibition with IC50 values 5.53 ± 0.02-91.50 ± 0.08 μM, most of which are superior to the standard thiourea (IC₅₀ = 21.00 ± 0.11 μM). In order to ensure the mode of inhibition of these compounds, the kinetic study of the most active compounds has been carried out. Most of these inhibitors were found to be mixed-type of inhibitors, except compounds 13 and 30 which were competitive, while compound 19 was identified as non-competitive inhibitor with Ki values between 8.6 and 19.29 μM.
    Matched MeSH terms: Enzyme Inhibitors/pharmacokinetics; Thiourea/pharmacokinetics
  17. Umar-Tsafe N, Mohamed-Said MS, Rosli R, Din LB, Lai LC
    Mutat. Res., 2004 Aug 8;562(1-2):91-102.
    PMID: 15279832
    Goniothalamin (GTN) is a styrylpyrrone derivative from Goniothalamus umbrosus and other Annonaceae species. It has been shown to have anti-cancer and apoptosis-inducing properties against various human tumour and animal cell lines. The compound has also been shown to be active in vivo against DMBA-induced rat mammary tumours and was reported as an anti-fertility agent in rats. The aim of our study was to assess the genotoxicity of GTN in CHO cells using the UKEMS guidelines. A metabolic activation fraction (S9) was prepared according to standard methods. The methylthiazoletetrazolium (MTT) screening assay was then carried out to determine the cytotoxicity index (IC50) of GTN. The average IC50 value was 12.45 (+/- 3.63)microM. The mitotic index (MI) assay was then performed to determine the clastogenicity indices (MI(C25), MI(C50) and MI(C100)) of GTN. The chromosome aberration (CA) induction assay using air-dried metaphase spread was then performed to investigate the clastogenic effects of goniothalamin. Benzo[a]pyrene (BaP) and ethylmethanesulphonate (EMS) were used as positive controls in the presence and absence of S9 metabolic activation, respectively. The anti-genotoxicity effect of GTN was also assessed using a combination of GTN and EMS, and GTN and BaP. Dose-responses of CA frequencies were determined for both, the genotoxicity and anti-genotoxicity effects. GTN on its own and when combined with positive controls, was found to induce and enhance CA, respectively. Chromatid and whole chromosome breaks/gaps, as well as interchanges, endoreduplications and ring chromosomes were the main types of aberration induced by GTN. The overall clastogenic effect of GTN was statistically significant. In conclusion, GTN is potentially a genotoxic or clastogenic substance without any anti-genotoxic properties.
    Matched MeSH terms: Mutagens/pharmacokinetics; Pyrones/pharmacokinetics
  18. Alam MZ
    Med. J. Malaysia, 2004 May;59 Suppl B:216-7.
    PMID: 15468895
    Studies on the removal of phenol from aqueous solutions by adsorption on sewage treatment plant biosolids (BS) as low-cost adsorbent were carried out with an aim to obtain information on treating phenol-containing wastewater from different industries. A series of experiments were undertaken in a batch adsorption technique to access the effect of the process variables i.e. initial phenol concentration, contact time, initial pH and adsorbent dose. The results showed that the adsorption capacity of BS in aqueous solution increased with the decrease in initial concentration and pH, and increase in contact time and dose of adsorbent. The experimental results were fitted by Langmuir and Freundlich isotherms to describe the biosorption processes.
    Matched MeSH terms: Water Pollutants, Chemical/pharmacokinetics*; Phenol/pharmacokinetics*
  19. Ahmed OH, Hussin A, Ahmad HM, Rahim AA, Majid NM
    ScientificWorldJournal, 2008 Apr 20;8:394-9.
    PMID: 18454247 DOI: 10.1100/tsw.2008.68
    Ammonia loss significantly reduces the urea-N use efficiency in crop production. Efforts to reduce this problem are mostly laboratory oriented. This paper reports the effects of urea amended with triple superphosphate (TSP) and zeolite (Clinoptilolite) on soil pH, nitrate, exchangeable ammonium, dry matter production, N uptake, fresh cob production, and urea-N uptake efficiency in maize (Zea mays) cultivation on an acid soil in actual field conditions. Urea-amended TSP and zeolite treatments and urea only (urea without additives) did not have long-term effect on soil pH and accumulation of soil exchangeable ammonium and nitrate. Treatments with higher amounts of TSP and zeolite significantly increased the dry matter (stem and leaf) production of Swan (test crop). All the treatments had no significant effect on urea-N concentration in the leaf and stem of the test crop. In terms of urea-N uptake in the leaf and stem tissues of Swan, only the treatment with the highest amount of TSP and zeolite significantly increased urea-N uptake in the leaf of the test crop. Irrespective of treatment, fresh cob production was statistically not different. However, all the treatments with additives improved urea-N uptake efficiency compared to urea without additives or amendment. This suggests that urea amended with TSP and zeolite has a potential of reducing ammonia loss from surface-applied urea.
    Matched MeSH terms: Nitrogen/pharmacokinetics*; Urea/pharmacokinetics*
  20. Abdullah AR, Sinnakkannu S, Tahir NM
    Bull Environ Contam Toxicol, 2001 Jun;66(6):762-9.
    PMID: 11353379
    Matched MeSH terms: Arylsulfonates/pharmacokinetics; Herbicides/pharmacokinetics
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