Home About us Contact
|
Home About us Contact | ||
|
|
||
Glycol Solution (glycol + solution)
Kinds of Glycol Solution Selected AbstractsInfluence of administration vehicles and drug formulations on the pharmacokinetic profile of lamotrigine in ratsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 5 2002M. M. Castel-Branco Abstract Given that administration vehicles and drug formulations can affect drug bioavailability, their influence on the pharmacokinetic profile of lamotrigine (LTG), a new-generation anti-epileptic drug, was studied in rats. Three different formulations administered intraperitoneally at a dose of 10 mg/kg were used: (1) LTG suspended in a 0.25% methylcelulose solution, (2) LTG dissolved in a 50% propylene glycol solution, and (3) LTG isethionate dissolved in distilled water. Plasma and brain homogenate levels were determined in order to evaluate vehicle-dependent drug absorption. The results demonstrated rapid absorption of LTG when it was administered as an aqueous solution, in contrast to a slower and more erratic absorption after the injection of either the lipophilic solution or the suspension. A plasma peak was achieved 15 min post-dose with the aqueous solution, with a brain peak being achieved 15 min later, while with the other formulations both plasma and brain homogenate peaks were reached 2 h after LTG administration. This study suggests that LTG isethionate dissolved in distilled water is the most suitable formulation for successful LTG pharmacokinetic studies in rats. [source] Microwave-Assisted Synthesis of Nanocrystalline MgO and Its Use as a BacteriocideADVANCED FUNCTIONAL MATERIALS, Issue 10 2005S. Makhluf Abstract Nanocrystalline particles of MgO were synthesized using microwave radiation in an ethylene glycol solution. The antibacterial activities of the MgO nanoparticles were tested by treating Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) cultures with 1,mg,mL,1 of the nanoparticles. We have examined the importance of the size effect, pH, and the form of the active MgO species as a bactericidal agent. A clear size dependence of the nanoparticles is observed where the amount of eradicated bacteria was strongly dependent on the particle size. [source] Viscosity measurements of ethylene glycol solution with flow drag reduction additivesHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 8 2006Naoto Haruki Abstract The viscous characteristics of ethylene glycol (EG) solution with flow drag reduction additive have been investigated experimentally. In this study, oleyldihydoroxyetyl amineoxide (ODEAO) was used as the flow drag reduction additive, and an aqueous solution of EG was used as a secondary refrigerant. The viscosity of the EG solution with ODEAO was measured with a rotational rheometer. The experimental parameters of viscosity measurement were the temperature of the EG solution with ODEAO, the ODEAO concentration, and the EG concentration. From the experimental results, the apparent viscosity of the EG solution with ODEAO showed SIS (shear induced state). The non-linear dependence of shear stress on shear rate has been well approximated by the power-law model under high shear conditions. The power-law contents, pseudoplastic viscosity, and index number have been estimated for each experimental parameter. Using the measured viscosity and non-dimensional analysis, the flow drag and heat transfer reduction effect of the EG solution with ODEAO has been investigated. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(8): 553,567, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20134 [source] A new biginelli reaction procedure using potassium hydrogen sulfate as the promoter for an efficient synthesis of 3,4-dihydropyrimidin-2(1H)-oneJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2004Shujiang Tu Simple and improved conditions have been found to carry out the Biginelli reaction for the synthesis of 3,4-dihydropyrimidin-2(1H)-one derivatives. This synthesis was performed using potassium hydrogen sulfate as the promoter in ethylene glycol solution. Compared with the classical Biginelli reaction conditions, this new method has the advantage of excellent yields (85,95%) and short reaction time (0.5,2 h). [source] Application of pressure-controlled colon delivery capsule to oral administration of glycyrrhizin in dogsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2001Nobuhito Shibata A colon delivery system has been used to improve the bioavailability of glycyrrhizin, a glycoside of glycyrrhetic acid. The bioavailability of glycyrrhizin is low when administered in conventional oral galenic dosage forms because glycyrrhizin is enzymatically hydrolysed both in the stomach and in the intestine. It was reasoned that if large amounts of glycyrrhizin were directly delivered to the colon, enzymatic activity should be reduced due to saturation so that intact glycyrrhizin could be absorbed into the systemic circulation. Based on this assumption, pressure-controlled colon delivery capsules (PCDCs) were used as a colon delivery system. Eight types of glycyrrhizin solution were prepared and were introduced into PCDCs. After oral administration of the test PCDCs to beagle dogs, blood samples were obtained over 24 h and plasma glycyrrhizin concentrations were measured by an HPLC method. With PCDCs containing aqueous glycyrrhizin and propylene glycol solutions, plasma glycyrrhizin levels were extremely low and the bioavailabilities of glycyrrhizin were 0.6% and 0.4%, respectively. When Labrasol was added to both types of glycyrrhizin solution, the bioavailability was improved to 4.6 % for aqueous solution and 3.8% for propylene glycol solution. When a surfactant, Polysorbate 80, was added in combination with Labrasol, synergistic effects were not obtained. Furthermore, dose-dependent effects of Polysorbate 80 were not obtained. Labrasol, which is a component of self-emulsifying drug delivery systems (SEDDS), has been shown to strongly improve the bioavailability of glycyrrhizin from the colon. [source] Synthesis and Photocatalytic Activity of Highly Ordered TiO2 and SrTiO3/TiO2 Nanotube Arrays on Ti SubstratesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 9 2010Xuming Zhang Highly ordered TiO2 nanotube arrays (TiO2 -NTAs) are produced by electrochemical anodization of a Ti foil in ammonium fluoride (NH4F),ethylene glycol solution. Photocatalytic (PC) investigations indicate that the length of the NTAs plays an important role in their photoactivity. The PC activity increases initially with the NT length and then decreases and the optimum length that yields the highest PC is 6.2 ,m for TiO2 -NTAs. The TiO2 -NTAs are further converted to heterojunction strontium titanate (SrTiO3)/TiO2 -NTAs by a hydrothermal reaction in Sr(OH)2 solution. As the hydrothermal reaction proceeds, more TiO2 is converted into SrTiO3 and the thickness of the SrTiO3 layer increases. The SrTiO3/TiO2 -NTAs exhibit variable PC activities that depend on the hydrothermal reaction time, and the SrTiO3/TiO2 -NTAs hydrothermally treated for 1 h or less have enhanced PC properties. The advantage of combining TiO2 and SrTiO3 stems from the difference in the flatband potential, thereby improving the separation of the photogenerated electron,hole pairs and consequently the PC activity. [source] Clinical trial: sodium phosphate tablets are preferred and better tolerated by patients compared to polyethylene glycol solution plus bisacodyl tablets for bowel preparationALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 10 2007G. R. LICHTENSTEIN Summary Background, Patient acceptance of bowel preparation can affect colon cancer screening compliance. Aim, To compare patient acceptance, preference and tolerability of 32-sodium phosphate tablets vs. 2L polyethylene glycol solution plus 4 bisacodyl tablets for bowel preparation. Methods, A prospective, randomized, investigator-blinded, multicentre trial was performed. Results were based on responses to a patient questionnaire. Results, 411 patients (205 sodium phosphate; 206 polyethylene glycol plus bisacodyl) completed the study preparation and patient questionnaire prior to colonoscopy. More patients receiving sodium phosphate vs. polyethylene glycol plus bisacodyl found it easy to take (77% vs. 42%), reported it to be without taste (47% vs. 6%), found it easy to take with respect to volume of liquid prescribed (72% vs. 27%) and indicated they would take the same preparation again in the future (96% vs. 74%, P < 0.0001 for all). Fewer patients receiving sodium phosphate vs. polyethylene glycol plus bisacodyl had to take time off work or change ordinary activities to take the study preparation (18% vs. 52%, P < 0.0001). Nausea, vomiting, bloating and abdominal pain were reported less frequently with sodium phosphate (P < 0.0013). Conclusion, The 32-tablet sodium phosphate dosing regimen was easier to take and better tolerated, when compared to 2L polyethylene glycol plus bisacodyl tablets for bowel preparation. [source] Inhibition of corrosion of AZ91 magnesium alloy in ethylene glycol solution in presence of chloride anionsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 2 2005E. Slavcheva Abstract The influence of chloride ions on the corrosion of AZ91 magnesium alloy in water/ethylene glycol solutions and the inhibiting effect of lactobiono-tallowamide (LTA) were investigated using electrochemical and surface analysis methods. Potentiodynamic polarization curves in aqueous solution of ethylene glycol (50:50w%) containing 0.1 g.L,1 chloride and up to 0.5 g.L,1 LBT were obtained at room and at elevated temperatures. The chloride anions showed a distinct deteriorating effect as they caused pit initiation and accelerated the dissolution of the tested alloy. The selected organic compound demonstrated good protective properties against corrosion of AZ91 magnesium alloy and behaved as inhibitor of mixed type hindering both the cathodic and the anodic partial reactions. It showed inhibition efficiency of 77% at relatively low concentration of 0.2 g.L,1 and was considered as a promising corrosion inhibitor. The mechanism of inhibition was discussed on the basis of the electrochemical impedance spectroscopy (EIS) and XRD analysis of the surface. [source] Application of pressure-controlled colon delivery capsule to oral administration of glycyrrhizin in dogsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2001Nobuhito Shibata A colon delivery system has been used to improve the bioavailability of glycyrrhizin, a glycoside of glycyrrhetic acid. The bioavailability of glycyrrhizin is low when administered in conventional oral galenic dosage forms because glycyrrhizin is enzymatically hydrolysed both in the stomach and in the intestine. It was reasoned that if large amounts of glycyrrhizin were directly delivered to the colon, enzymatic activity should be reduced due to saturation so that intact glycyrrhizin could be absorbed into the systemic circulation. Based on this assumption, pressure-controlled colon delivery capsules (PCDCs) were used as a colon delivery system. Eight types of glycyrrhizin solution were prepared and were introduced into PCDCs. After oral administration of the test PCDCs to beagle dogs, blood samples were obtained over 24 h and plasma glycyrrhizin concentrations were measured by an HPLC method. With PCDCs containing aqueous glycyrrhizin and propylene glycol solutions, plasma glycyrrhizin levels were extremely low and the bioavailabilities of glycyrrhizin were 0.6% and 0.4%, respectively. When Labrasol was added to both types of glycyrrhizin solution, the bioavailability was improved to 4.6 % for aqueous solution and 3.8% for propylene glycol solution. When a surfactant, Polysorbate 80, was added in combination with Labrasol, synergistic effects were not obtained. Furthermore, dose-dependent effects of Polysorbate 80 were not obtained. Labrasol, which is a component of self-emulsifying drug delivery systems (SEDDS), has been shown to strongly improve the bioavailability of glycyrrhizin from the colon. [source] Inhibition of corrosion of AZ91 magnesium alloy in ethylene glycol solution in presence of chloride anionsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 2 2005E. Slavcheva Abstract The influence of chloride ions on the corrosion of AZ91 magnesium alloy in water/ethylene glycol solutions and the inhibiting effect of lactobiono-tallowamide (LTA) were investigated using electrochemical and surface analysis methods. Potentiodynamic polarization curves in aqueous solution of ethylene glycol (50:50w%) containing 0.1 g.L,1 chloride and up to 0.5 g.L,1 LBT were obtained at room and at elevated temperatures. The chloride anions showed a distinct deteriorating effect as they caused pit initiation and accelerated the dissolution of the tested alloy. The selected organic compound demonstrated good protective properties against corrosion of AZ91 magnesium alloy and behaved as inhibitor of mixed type hindering both the cathodic and the anodic partial reactions. It showed inhibition efficiency of 77% at relatively low concentration of 0.2 g.L,1 and was considered as a promising corrosion inhibitor. The mechanism of inhibition was discussed on the basis of the electrochemical impedance spectroscopy (EIS) and XRD analysis of the surface. [source] Experimental investigation on chemical sensor based on a multimode fiber Bragg gratingMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 9 2006Xinzhu Sang Abstract A chemical sensor based on a Bragg grating in the multimode fiber has been demonstrated experimentally. Experimental results indicate that the reflection peak of high-order mode P2 exhibits a much higher concentration sensitivity of the chemical solution than the reflection peak P1 of the high-order mode. The sensor has been used to measure the concentrations of propylene glycol solutions and sugar solutions, which could detect 0.05% and 0.04% concentration change for them with the wavelength interrogation module of 1-pm resolution. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1739,1741, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21761 [source] Detection of l -lactate in polyethylene glycol solutions confirms the identity of the active-site ligand in a proline dehydrogenase structureACTA CRYSTALLOGRAPHICA SECTION D, Issue 5 2004Min Zhang Polyethylene glycol (PEG) is often used in protein crystallography as a low-ionic-strength precipitant for crystallization and as a cryoprotectant for low-temperature data collection. Prompted by the discovery of an apparent l -lactate molecule bound in the active site of the Escherichia coli PutA proline dehydrogenase domain crystal structure, the l -lactate concentration of several PEG solutions was measured. 50%(w/v) solutions of PEGs with molecular weight 3000, 4000 and 8000 contain millimolar levels of l -lactate. In contrast, l -lactate was not detected in solutions of PEG monomethyl ethers or PEG 3350. These results help to explain why l -lactate was present in the proline dehydrogenase domain crystal structure. This work also has implications for the crystallization of enzymes that bind l -lactate. [source] Crystallization of gankyrin, an oncoprotein that interacts with CDK4 and the S6b (rpt3) ATPase of the 19S regulator of the 26S proteasomeACTA CRYSTALLOGRAPHICA SECTION D, Issue 7 2003Szymon Krzywda Gankyrin is an oncoprotein overexpressed in hepatocarcinoma cells that binds to the cell-cycle regulator CDK4 and the S6b ATPase subunit of the regulatory component of the proteasome. It belongs to the family of ankyrin-repeat proteins that appear to mediate protein,protein interactions in diverse biochemical processes. Gankyrin has been crystallized from polyethylene glycol solutions and diffraction data have been obtained from these crystals that extend to 2.1,Å spacing. [source] Crystallization and preliminary X-ray analysis of a rat aldose reductase-like protein (AKR1B14)ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2009Roland Chung Mouse vas deferens protein/aldo-keto reductase 1B7 (AKR1B7) is involved in the detoxification of isocaproaldehyde, a steroidogenesis byproduct, and of 4-hydroxynonenal formed by lipid peroxidation. The rat orthologue of AKR1B7 has recently been named AKR1B14 in the AKR superfamily. Recombinant AKR1B14 was expressed in a bacterial system and purified to homogeneity. The purified protein was crystallized from polyethylene glycol solutions using the hanging-drop vapour-diffusion method and an X-ray diffraction data set was collected to 1.86,Å resolution. The crystals belonged to space group P21, with unit-cell parameters a = 50.66, b = 69.14, c = 72.27,Å, , = 96.4°. This is the first crystallization report of a rodent AKR1B7 orthologue. [source] Crystallization and preliminary X-ray diffraction analysis of human IL-22 bound to its soluble decoy receptor IL-22BPACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 2 2009Leandra Watanabe Interleukin-22 (IL-22) is a pleiotropic cytokine that is involved in inflammatory responses. Human IL-22 was incubated with its soluble decoy receptor IL-22BP (IL-22 binding protein) and the IL-22,IL-22BP complex was crystallized in hanging drops using the vapour-diffusion method. Suitable crystals were obtained from polyethylene glycol solutions and diffraction data were collected to 2.75,Å resolution. The crystal belonged to the tetragonal space group P41, with unit-cell parameters a = b = 67.9, c = 172.5,Å, and contained two IL-22,IL-22BP complexes per asymmetric unit. [source] Crystallization and preliminary X-ray diffraction analysis of the Fab fragment of WO2, an antibody specific for the A, peptides associated with Alzheimer's diseaseACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 5 2008Kwok S. Wun The murine monoclonal antibody WO2 specifically binds the N-terminal region of the amyloid , peptide (A,) associated with Alzheimer's disease. This region of A, has been shown to be the immunodominant B-cell epitope of the peptide and hence is considered to be a basis for the development of immunotherapeutic strategies against this prevalent cause of dementia. Structural studies have been undertaken in order to characterize the molecular basis for antibody recognition of this important epitope. Here, details of the crystallization and X-ray analysis of the Fab fragment of the unliganded WO2 antibody in two crystal forms and of the complexes that it forms with the truncated A, peptides A,1,16 and A,1,28 are presented. These crystals were all obtained using the hanging-drop vapour-diffusion method at 295,K. Crystals of WO2 Fab were grown in polyethylene glycol solutions containing ZnSO4; they belonged to the orthorhombic space group P212121 and diffracted to 1.6,Å resolution. The complexes of WO2 Fab with either A,1,16 or A,1,28 were cocrystallized from polyethylene glycol solutions. These two complex crystals grew in the same space group, P212121, and diffracted to 1.6,Å resolution. A second crystal form of WO2 Fab was grown in the presence of the sparingly soluble A,1,42 in PEG 550 MME. This second form belonged to space group P21 and diffracted to 1.9,Å resolution. [source] | |||||||||||||||||||