bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinetics of heavy metal desorption from three soils using citric acid, tartaric acid, and EDTA
Authors: Wasay S.A. , Barrington S. , Tokunagal S. , Prasher S. 
Published: December 2007

Organic acids are relatively new soil heavy metal leaching agents requiring the development of desorption kinetics before being applied. The objective was to determine the heavy metal desorption rates for three heavily contaminated soils (clay loam, loam, and sandy clay loam), treated under optimum conditions with either citric acid, tartaric acid, or EDTA for comparison. A two-rate reaction (fast and slow) model was defined to describe desorption kinetics, where both first order rates were assumed irreversible and reversible, respectively. Experimental data were collected by initially subjecting the three soils to batch experiments at optimum leaching agent level, for up to 36 h. The results indicated that citric acid was a more consistent leaching agent compared to tartaric acid and EDTA, which were efficient mainly in treating the clay loam and the sandy clay loam, respectively. The two-rate reaction model fitted the data but its empirical coefficients need to be defined for each individual soil to be treated. For Pb common to all three experimental soils, k1, representing the fast desorption rate, increased with the ratio of metal equivalence fraction: soil CEC. The coefficients k2and α0, representing the slower rate of desorption and the proportion of Pb involved in this slow rate, respectively, increased with the mass of Pb held by the oxide and organic matter fractions. The coefficient m1, related to the relative rate of the backward reaction from the slow to the fast, varied according to the mass of Pb held by the exchangeable site. Despite the empirical values associated with the kinetics coefficients, their correspondence with individual processes indicate that organic acid remediation can be modeled using the two rate kinetic equation proposed in this project.
Phosphorus adsorption and oven dried alum residual solids in fixed bed column experiments
Authors: Mortula M.M. , Gagnon G.A. 
Published: December 2007

In this study, fixed bed columns were used to evaluate the effectiveness of phosphorus adsorption on oven dried alum residual solids. The effect of key operating parameters (pH, particle size, and initial phosphorus concentration) on the effectiveness of phosphorus removal was investigated. The results indicated that phosphorus removal using oven dried alum residual solids was effective and comparable to granular activated carbon. Statistical analysis showed that the effect of particle size on the breakthrough pore volume processed was significant, but the effect of pH was inconclusive. Aluminum leaching was found to be higher than 20 mg/L for an influent pH level of 3. The effectiveness of phosphorus removal was affected by initial phosphorus concentration. However, initial phosphorus concentration did not appear to have any considerable effect on aluminum and organic leaching.
Performance evaluation of fabric aided slow sand filter in drinking water treatment
Authors: Mondal Pulin Kumar , Seth Rajesh , Biswas Nihar 
Published: December 2007

In this study, an assessment of the performance of slow sand filter (SSF) aided with non-woven fabric (NWF) was carried out. Several laboratory-scale SSF columns were tested with simulated raw water containing varying levels of turbidity and total organic carbon (TOC). The results show that in filters with NWF, the fabric layers captured most of the incoming solids and extended the filter run time for the sand bed. The run time for the sand bed increased with the increasing of the fabric thickness from 8.9 to 44.5 mm. Turbidity, TOC, and bacterial removal efficiencies of the filters with fabric were comparable to that without fabric and representing conventional SSF. The study thus demonstrates that operation of SSF with NWF can be a feasible option for simplifying the operation of and extending the viability of the SSF process to a wider range of raw water turbidity values than that considered economical for conventional SSF.
Autothermal thermophilic aerobic digestion (ATAD) — Part II: Review of research and full-scale operating experiences
Authors: Layden Noreen M. , Kelly Harlan G. , Mavinic Donald S. , Moles Richard , Bartlett John 
Published: December 2007

Autothermal thermophilic aerobic digestion (ATAD) is an exothermic process where sludge is subjected to temperatures greater than 55 °C for at least 4 hours, over 6–10 days. Organic solids are degraded and the heat released during the microbial degradation is used to bring the process temperature within the thermophilic range. It produces a biologically stable product, achieving a reduction in biomass, while using smaller digesters, compared to mesophilic aerobic and anaerobic digestion. There are no regulatory requirements in North America and Europe for the reduction of the volume of total solids in sludge processing. However, a reduction in the volume of material for final disposal has cost benefits. By virtue of the residual mass, volume reductions are easily made through dewatering or dehydrating steps following ATAD. Despite the apparent advantages of ATAD, limited information on the process is available in the literature. Concerns still exist about documented cases of odour issues, problems with sludge dewaterability, foaming, excess use of polymers and high-energy consumption. This article presents some relevant bench-scale and pilot ATAD study data, with appropriate discussion. It also assembles information from a range of sources and provides an insight into actual application and experiences with full-scale ATAD.
A Bayesian Framework for Multimodel Regression
Authors: DelSole Timothy 
Published: December 2007

AbstractThis paper presents a framework based on Bayesian regression and constrained least squares methods for incorporating prior beliefs in a linear regression problem. Prior beliefs are essential in regression theory when the number of predictors is not a small fraction of the sample size, a situation that leads to overfitting—that is, to fitting variability due to sampling errors. Under suitable assumptions, both the Bayesian estimate and the constrained least squares solution reduce to standard ridge regression. New generalizations of ridge regression based on priors relevant to multimodel combinations also are presented. In all cases, the strength of the prior is measured by a parameter called the ridge parameter. A “two-deep” cross-validation procedure is used to select the optimal ridge parameter and estimate the prediction error.The proposed regression estimates are tested on the Development of a European Multimodel Ensemble System for Seasonal to Interannual Prediction (DEMETER) hindcasts of seasonal mean 2-m temperature over land. Surprisingly, none of the regression models proposed here can consistently beat the skill of a simple multimodel mean, despite the fact that one of the regression models recovers the multimodel mean in a suitable limit. This discrepancy arises from the fact that methods employed to select the ridge parameter are themselves sensitive to sampling errors. It is plausible that incorporating the prior belief that regression parameters are “large scale” can reduce overfitting and result in improved performance relative to the multimodel mean. Despite this, results from the multimodel mean demonstrate that seasonal mean 2-m temperature is predictable for at least three months in several regions.
Dosage plan of a flurbiprofen injection product using inhibition of protein binding by lipid emulsion in rats
Authors: Ogata Kenji , Takamura Norito , Tokunaga Jin , Kawai Keiichi , Arimori Kazuhiko , Higuchi Shun 
Published: December 2007

Abstract
Flurbiprofen-axetil (FP-ax), a bolus injection product of a non-steroidal anti-inflammatory drug (NSAID), is a prodrug of flurbiprofen, an NSAID. As flurbiprofen strongly binds to site II of human serum albumin (HSA), the free (unbound) concentration of flurbiprofen after injection of FP-ax is low. We have examined the inhibitory effect of free fatty acid (FFA), a binding inhibitor for site II of HSA, on the binding of flurbiprofen in-vitro and in-vivo by ultrafiltration, to establish an effective dosage of FP-ax. In-vitro, fatty acid mixtures (FAs) inhibited the binding of flurbiprofen to rat serum albumin. The free fraction of flurbiprofen was remarkably increased by FAs in rat serum. In-vivo, FP-ax was injected into a control group (low FFA concentration in serum) and a lipid emulsion group (high FFA concentration in serum). The area under the curve of the free concentration of flurbiprofen during the alpha phase and the distribution volume of the central compartment of flurbiprofen were significantly higher in the lipid emulsion group than the control group (5.0- and 1.2-times, respectively). When FP-ax was administered at high FFA concentration, the free concentration of flurbiprofen and distribution of flurbiprofen to tissues increased transiently. This administration method may be useful for patients with cancer pain, having a potent analgesic effect.
Synergistic effect of iontophoresis and soluble microneedles for transdermal delivery of methotrexate
Authors: Vemulapalli Viswatej , Yang Ye , Friden Phillip M , Banga Ajay K 
Published: December 2007

Abstract
The aim of this study was to investigate the transdermal iontophoretic delivery of methotrexate, alone or in combination with microneedles, in-vitro and in-vivo using intracutaneous microdialysis in the hairless rat. The average depth of the microdialysis probe in the skin was found to be 0.54 mm. Methotrexate was stable in the presence of an applied electric field as determined by cyclic voltammetry. A current density of 0.4 mA cm−2 applied for 60 min was used in combination with maltose microneedles to enhance delivery of methotrexate across the skin. Delivery was enhanced by iontophoresis and microneedles, both in-vitro and in-vivo. A synergistic 25-fold enhancement of delivery was observed in-vivo when a combination of microneedles and iontophoresis was used compared with either modality alone.
Effects of CYP inducers and inhibitors on the pharmacokinetics of intravenous theophylline in rats: involvement of CYP1A1/2 in the formation of 1,3-DMU
Authors: Yang Kyung H , Lee Joo H , Lee Myung G 
Published: December 2007

AbstractThe types of hepatic cytochrome P450 (CYP) isozymes responsible for the metabolism of theophylline and for the formation of 1,3-dimethyluric acid (1,3-DMU) in rats in-vivo does not seem to have been studied at the dose ranges of dose-independent metabolic disposition of theophylline in rats (up to 10 mg kg−1). Therefore, theophylline (5 mg kg−1) was administered i.v. to male Sprague—Dawley rats pretreated with various inducers and inhibitors of CYP isozymes. In rats pretreated with 3-methylcholanthrene (3-MC), orphenadrine or dexamethasone (main inducers of CYP1A1/2, CYP2B1/2 and CYP3A1/2, respectively, in rats), the time-averaged non-renal clearance (CLNR) of theophylline was significantly faster than in their respective controls (1260, 42.7 and 69.0% increases, respectively). However, in rats pretreated with troleandomycin (a major inhibitor of CYP3A1/2 in rats), CLNR was significantly slower than in the controls (50.7% decrease). The 24 h urinary excretion of 1,3-DMU was increased significantly only in rats pretreated with 3-MC. The ratio of area under the curve for 1,3-DMU and theophylline (AUC1,3-DMU/AUCtheophylline) was increased significantly in rats pretreated with 3-MC (160% increase) and decreased significantly in rats pretreated with troleandomycin (50.1% decrease); however, the ratio was not increased in rats pretreated with dexamethasone. These data suggest that theophylline is primarily metabolized via CYP1A1/2, CYP2B1/2, and CYP3A1/2, and that 1,3-DMU is primarily formed via CYP1A1/2, and possibly CYP3A1/2, in rats.
Involvement of Mrp2 (Abcc2) in biliary excretion of moxifloxacin and its metabolites in the isolated perfused rat liver
Authors: Ahmed Salwa , Vo Nha T P , Thalhammer Theresia , Thalhammer Florian , Gattringer Klaus-Bernhard , Jäger Walter 
Published: December 2007

AbstractMoxifloxacin is a novel antibacterial agent that undergoes extensive metabolism in the liver to the glucuronide M1 and the sulfate M2, which are eliminated via the bile. To investigate the role of the multidrug resistance-associated protein (Mrp2) as the hepatic transport system for moxifloxacin and its conjugates, livers of Wistar and Mrp2-deficient TR− rats were perfused with moxifloxacin (10 μM) in a single-pass system. Values for the hepatic extraction ratio (E) and clearance (Cl) were insignificantly higher in TR− rats than Wistar rats (0.193 ± 0.050 vs 0.245 ± 0.050 for E; 6.85 ± 1.96 vs 8.73 ± 1.82 mL min−1 for Cl), whereas biliary excretion and efflux into perfusate over 60 min were significantly lower in the mutant rat strain. Cumulative biliary excretion of M1, M2 and moxifloxacin was significantly reduced to 0.027%, 19.1%, and 29.6% in the TR− rats compared with Wistar rats, indicating that the biliary elimination of M1 is mediated exclusively by Mrp2, whereas that of M2 and moxifloxacin seems to depend mostly on Mrp2 and, to a smaller extent, a further unidentified canalicular transporter. Moxifloxacin stimulates bile flow by up to 11% in Wistar rats, but not in TR− rats, further supporting an efficient transport of this drug and its glucuronidated and sulfated metabolites by Mrp2. Moxifloxacin (10 μM) also reversibly inhibited the Mrp2-mediated biliary elimination of bromsulphthalein in Wistar rats by 34%, indicating competition with the elimination of Mrp2-specific substrates. In conclusion, we found that Mrp2 mediates the biliary elimination of moxifloxacin and its glucuronidated and sulfated metabolites in rats. MRP2 may therefore play a key role in the transport of moxifloxacin and its conjugates into bile in humans.
Measurements of rat and mouse gastrointestinal pH, fluid and lymphoid tissue, and implications for in-vivo experiments
Authors: McConnell Emma L , Basit Abdul W , Murdan Sudaxshina 
Published: December 2007

Abstract
To use rodent models effectively in in-vivo investigations on oral drug and vaccine delivery, the conditions in the gastrointestinal tract must be understood. Some fundamental information is currently unavailable or incomplete. We have investigated the pH, water content and lymphoid tissue distribution along the gastrointestinal tract, as well as the stomach volume, as these were critical to our investigations on pH-responsive drug delivery and colonic vaccination. The observed values were compared with those in man as an indication of the validity of the rodent model. The mouse stomach pH was 3.0 (fed) and 4.0 (fasted), and the corresponding values in the rat were 3.2 (fed) and 3.9 (fasted). The mean intestinal pH was lower than that in man (&lt; pH 5.2 in the mouse; &lt; pH 6.6 in the rat). This brings into question the use of rodents in investigations on enteric-coated drug carriers targeted to the large intestine/distal gut. The water content in the gastrointestinal tract in the fed and fasted mouse was 0.98 ± 0.4 and 0.81 ± 1.3 mL, respectively, and in the fed and fasted rat was 7.8 ± 1.5 and 3.2 ± 1.8 mL. When normalized for body weight, there was more water per kg body weight in the gastrointestinal tracts of the mouse and rat, than in man. The stomach capacity was found to be approximately 0.4 and 3.4 mL for mice and rats, respectively. The low fluid volume and stomach capacity have implications for the testing of solid dosage forms in these animal models. Substantial amounts of lymphoid tissue analagous to small intestinal Peyer's patches were measured in the rat and mouse colon, showing the feasibility of colonic vaccination, a route which might prove to have different applications to the more commonly studied oral vaccines. The existence of lymphoid tissue in the mouse and rat caecum has also been reported.
Percutaneous penetration of felbinac after application of transdermal patches: relationship with pharmacological effects in rats
Authors: Shinkai Norihiro , Korenaga Kazuko , Takizawa1 Hiromi , Mizu Hideo , Yamauchi Hitoshi 
Published: December 2007

Abstract
We have evaluated the percutaneous penetration of felbinac following application of topical patches using a microdialysis technique, and have examined correlations with pharmacological effects. A linear microdialysis probe with a 20-mm dialysis fibre was inserted into the skin of anaesthetized rats. Probe perfusion was started at 2.0 μL min−1 with physiological saline and after a 60-min baseline sampling of dialysate, 0.1 mL croton oil was applied to the skin surface at a concentration of 8%, v/v. A felbinac patch was then applied to the same point 60 min thereafter and dialysate was sampled at 60-min intervals up to 300 min after patch application, for determination of concentrations of felbinac and prostaglandin (PG) E2. Analgesic effects of felbinac patches in an iodoacetate-induced osteoarthritis model and an incisional pain model were evaluated using the weight bearing method. After application of patches, felbinac penetration into the skin was rapid, maximum concentrations in the dialysates with 0.07, 0.5 and 3.5% w/w felbinac patches being 0.046 ± 0.02, 0.104 ± 0.06 and 0.244 ± 0.2 μg mL−1, respectively. Dermal administration of croton oil caused an increment in PGE2 levels, which was significantly decreased by 0.5 and 3.5% felbinac patches 2–5 h after application. In pharmacological studies, 3.5% felbinac patches suppressed pain-associated behaviour induced by iodoacetate injection and plantar incision. These results suggested that the transdermal patch containing 3.5% felbinac may become a useful formulation.
Semi-mechanistic description of the in-vitro antiproliferative effect of different antitumour agents
Authors: Moreno Daniel , Trocóniz Iñaki F , Enguita Mónica , Bandrés Eva , García-Foncillas Jesús , Garrido María J 
Published: December 2007

AbstractThe aim of the present work was to describe the antiproliferative effect of camptothecin (CPT), topotecan (TPT) and cisplatin (CIS) in cultured cells using a semi-mechanistic pharmacodynamic approach. This effect on the growth of DHD-K12PROb cells was modelled as a function of drug concentration and time of exposure using the Gompertz framework. Models reflected two major processes: cell proliferation and cell death/degradation. Antiproliferative effect of CPT and TPT was described as inhibition of cell proliferation, while the effect of CIS was described as stimulation of cell death, including a signal transduction process, reflected as a delay in the onset of drug action. The half-life associated with such a transduction process was estimated to be approximately 27 h. Interestingly, the time profiles of the model predicted a signal transduction process that closely resembled the observed profiles of caspase-3, a protein implicated in CIS-mediated apoptosis. Therefore, the combination of a simple and sensitive design, together with an appropriated modelling strategy, allowed us to explore different mechanisms of action for antitumour agents in cultured cells and to obtain information about the dynamics of signal transduction and the potential use of biomarkers.
Glycyrrhizin prevents of lipopolysaccharide/D-galactosamine-induced liver injury through down-regulation of matrix metalloproteinase-9 in mice
Authors: Abe Kazuki , Ikeda Tadayuki , Wake Kenjiro , Sato Tetsuji , Sato Toshitsugu , Inoue Hideo 
Published: December 2007

Abstract
Glycyrrhizin, a biological active compound isolated from the liquorice root, has been used as a treatment for chronic hepatitis. We have examined the involvement of matrix metalloproteinase (MMP)-9 in the development of lipopolysaccharide (LPS) and D-galactosamine (GalN)-induced liver injury in mice. We also investigated the effect of glycyrrhizin on expression of MMP-9 in this model. Levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) increased after LPS/GalN treatment. Expression of MMP-9 mRNA and protein was markedly up-regulated in liver tissues 6–8 h after LPS/GalN treatment. Pretreatment with glycyrrhizin (50 mg kg−1) and the MMP inhibitor (5 mg kg−1) suppressed increases in serum levels of ALT and AST in mice treated with LPS/GalN. Furthermore, glycyrrhizin inhibited levels of both mRNA and protein for MMP-9. Immunohistochemical reaction for MMP-9 was observed in macrophages/monocytes infiltrated in the inflammatory area of liver injury. Glycyrrhizin reduced the infiltration of inflammatory cells and immunoreactive MMP-9 in liver injury. The results indicated that MMP-9 played a role in the development of LPS/GalN-induced mouse liver injury, and suggested that an inhibition by glycyrrhizin of the acute liver injury may have been due to a down-regulation of MMP-9.
Optimization and validation of a chromatographic method for the simultaneous quantification of six bioactive compounds in Rhizoma et Radix Polygoni Cuspidati
Authors: Qian Guangsheng , Leung Sik-Yuen , Lu GuangHua , Leung Kelvin Sze-Yin 
Published: December 2007

Abstract
A reverse-phase HPLC method was developed for simultaneous quantification of six bioactive compounds in Rhizoma et Radix Polygoni Cuspidati. These compounds — polydatin (1), resveratrol (2), rhein (3), emodin (4), chrysophanol (5) and physcion (6) — were analysed from 24 authentic samples of the herb using UV HPLC. Based on the UV absorption characteristics of the six compounds, absorption wavelengths of 306 nm were chosen to quantify compounds 1 and 2, and 290 nm for compounds 3–6. A reliable and reproducible quantitative HPLC method for analysing authentic samples of Rhizoma et Radix Polygoni Cuspidati from different cultivation regions was developed. The results showed that the concentration of compound 1 in samples from Sichuan was almost 2-fold higher than that of samples acquired in Guangxi. Furthermore, compounds 3 and 5 were not found in all the samples tested. Thus, instead of using polydatin (1) and emodin (4) as markers for quality assessment, as in conventional practice, these findings show that compounds 2 and 6 are more suited to act as marker compounds for a more specific assessment of the quality of this herb.
(—)-Epigallocatechin gallate (EGCG) prevents isoprenaline-induced cardiac toxicity by stabilizing cardiac marker enzymes and membrane-bound ATPases
Authors: Devika Periyathambi Thangappan , Prince Ponnian Staneley Mainzen 
Published: December 2007

Abstract
Intake of tea flavonoids has been reported to reduce the incidence of cardiovascular disease. The present study was undertaken to investigate the preventive effect of (—)epigallocatechin gallate (EGCG) on heart weight, cardiac marker enzymes, membrane-bound ATPases and electrolytes in isoprenaline (ISO)-induced myocardial infarcted (MI) Wistar rats. Rats subcutaneously administered ISO 100 mgkg−1 at intervals of 24 h for 2 days resulted in significant increases in heart weight and the activities of cardiac marker enzymes such as creatine kinase, creatine kinase-MB, lactate dehydrogenase (LDH), aspartate transaminase and alanine transaminase in serum, and significant decreases in the activities of these enzymes in the myocardium. ISO injection also increased levels of LDH isoenzymes (LDH 1 and LDH 2). The activity of Na+/K+ ATPase was decreased significantly and the activities of Ca2+ and Mg2+ ATPases were increased significantly in ISO-induced MI rats. Furthermore, the levels of potassium were lowered and the levels of sodium and calcium were increased in ISO-induced MI rats. Prior treatment with EGCG (10, 20 and 30 mgkg−1) daily for a period of 21 days reduced the effects of ISO on heart weight, activities of cardiac marker enzymes and membrane bound-ATPases and levels of LDH 1 and LDH 2 and electrolytes. Thus, EGCG exhibits beneficial effects on these enzymes and electrolytes. The observed effects may be due to the antioxidant and membrane-stabilizing effects of EGCG in ISO-induced MI rats.