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Different Formulations (different + formulations)
Selected AbstractsProspects for therapeutic vaccination with glatiramer acetate for neurodegenerative diseases such as Alzheimer's diseaseDRUG DEVELOPMENT RESEARCH, Issue 2 2002Michal Schwartz Abstract Neurodegenerative diseases, whatever their primary causes, are characterized by certain common features, one of which is their self-perpetuating nature. The ongoing progression of the disorder is due to the effects of destructive self-compounds, whose presence in the tissues is an outcome of the early phase of the disease and which gradually destroy remaining functional neurons. Studies in our laboratory have led to the recent formulation of a novel concept of protective autoimmunity as the body's mechanism of defense against these destructive self-compounds. This autoimmune response to central nervous system (CNS) insults is mediated by T-cells and presumably operates by activating and regulating local microglia and infiltrating macrophages (inflammatory response) to carry out their function of clearing destructive material from the tissue at risk. We suggest that a well-controlled autoimmunity counteracts and overcomes the destructive effects of the potentially harmful self-compounds, at the cost of some loss of tissue. An additional risk to the individual is the induction of an autoimmune disease, which is likely to occur if the autoimmune response is malfunctioning. An optimal balance of the various factors will lead to an outcome of maximal benefit at minimal cost to the tissue. A procedure for safely boosting the autoimmune response, by vaccination with a weak self-crossreactive antigen such as glatiramer acetate (also known as Cop-1) was found to protect rats from glutamate toxicity, a major mediator of the spread of damage and a well-known causative factor in neurodegenerative disorders. Cop-1, when administered according to a different regimen, is an FDA-approved drug for the treatment of multiple sclerosis. Different formulations of the same drug can therefore be used to treat two extreme manifestations of chronic degenerative diseases of the CNS. Drug Dev. Res. 56:143,149, 2002. © 2002 Wiley-Liss, Inc. [source] Higher-order XFEM for curved strong and weak discontinuitiesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2010Kwok Wah Cheng Abstract The extended finite element method (XFEM) enables the accurate approximation of solutions with jumps or kinks within elements. Optimal convergence rates have frequently been achieved for linear elements and piecewise planar interfaces. Higher-order convergence for arbitrary curved interfaces relies on two major issues: (i) an accurate quadrature of the Galerkin weak form for the cut elements and (ii) a careful formulation of the enrichment, which should preclude any problems in the blending elements. For (i), we employ a strategy of subdividing the elements into subcells with only one curved side. Reference elements that are higher-order on only one side are then used to map the integration points to the real element. For (ii), we find that enrichments for strong discontinuities are easily extended to higher-order accuracy. In contrast, problems in blending elements may hinder optimal convergence for weak discontinuities. Different formulations are investigated, including the corrected XFEM. Numerical results for several test cases involving strong or weak curved discontinuities are presented. Quadratic and cubic approximations are investigated. Optimal convergence rates are achieved using the standard XFEM for the case of a strong discontinuity. Close-to-optimal convergence rates for the case of a weak discontinuity are achieved using the corrected XFEM. Copyright © 2009 John Wiley & Sons, Ltd. [source] Studying and increasing light stability of rotomolding grade of polyethyleneJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008E. Feyz Abstract This article covers the state-of-the-art light stabilizer for rotational molding and the influence of synergistic effects between light and thermal stabilizers, which improve physical and mechanical properties. Different formulations of polyethylene (PE) with light stabilizer, thermal stabilizer, and acid scavenger have been produced in twin-screw extruder. To study the light stability, sheets that produced by injection-molding machine have been put in weather-ometer instrument for 1000 h. After and before that, physical and mechanical properties have been evaluated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Increased effectiveness of the Trichoderma harzianum isolate T-78 against Fusarium wilt on melon plants under nursery conditionsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2009Agustina Bernal-Vicente Abstract BACKGROUND: The use of isolates of the genus Trichoderma to control Fusarium wilt in melon plants is one of the most recent and effective alternatives to chemical treatments. In this work we have studied the immobilization of the isolate Trichoderma harzianum T-78 on different carriers as an efficient method to control vascular Fusarium wilt of melon in nurseries. Different formulations were developed: liquids (spore suspension, guar gum and carboxymethylcellulose) and solids (bentonite, vermiculite and wheat bran). RESULTS: The introduction of F. oxysporum resulted in a significant decrease in seedling fresh weight. The treatments which gave a lesser reduction in weight and showing a greater biocontrol effect were the liquid conidial suspension and the solid treatments with bentonite and superficial vermiculite. Microbiological analyses revealed that the conidial suspension and all the solid treatments, except wheat bran, significantly decreased F. oxysporum populations. Of all the treatments assayed, bentonite produced the greatest decline in the F. oxysporum population. CONCLUSIONS: The most effective treatments against Fusarium wilt on melon plants were the solid treatments bentonite and superficial vermiculite. These two treatments gave the greatest plant weight, the lowest percentage of infected plants and the greatest T. harzianum population throughout the assay. Copyright © 2009 Society of Chemical Industry [source] Association between plasticized starch and polyesters: Processing and performances of injected biodegradable systemsPOLYMER ENGINEERING & SCIENCE, Issue 5 2001Luc Avérous Different formulations of wheat thermoplastic starch (TPS) have been processed with various plasticizer/starch ratios and moisture contents. The biodegradable polyesters tested are polycaprolactone (PCL), polyester amide (PEA), polybutylene succinate adipate (PBSA) and polybutylene adipate co terephtalate (PBAT). TPS and polyesters are melt blended in different proportions by extrusion and then injected to obtain dumbbell specimens. Various properties are evaluated such as the mechanical properties (tensile and impact tests), and the hydrophilic character with contact angle measurements. Additionally, uniaxial shrinkage is evaluated. Results show that the addition of polyester to TPS increases the dimensional post-injection stability. Blend modulus values are close to the results of the classical rule of mixture. Elongation at break, resilience values and SEM observations seem to give some indications about the compatibility between both polymeric systems. PBAT and PEA present better results than PCL and PBSA. Contact angle measurement show that we have a drastic increase of the hydrophobic character from 10% of polyester in the blend. The different combinations of TPS and polyesters give a wide range of mechanical behavior for compostable materials, to be developed in specific applications. [source] An in vivo model to evaluate the efficacy of barrier creams on the level of skin penetration of chemicalsCONTACT DERMATITIS, Issue 1 2006Alexa Teichmann The reservoir function and the barrier function are important properties of the skin. The reservoir function is dependent on the barrier function which, however, needs support by protective measures, in particular under working conditions. Barrier creams represent a possibility to protect the skin. In the present study, a method was developed to investigate the effectiveness of reservoir closure by different formulations. Patent Blue V in water was used as a model penetrant. Its penetration, with and without barrier cream treatment, was analyzed by tape stripping in combination with UV/VIS spectroscopic measurements. The investigations showed that the stratum corneum represents a reservoir for topically applied Patent Blue V in water. Furthermore, the barrier investigations showed that vaseline and bees wax form a 100% barrier on the skin surface. The third barrier cream, containing waxes and surfactant, only partially showed a protective effect against the penetration of Patent Blue V in water. Strong interindividual differences were observed for this barrier product. In conclusion, it was assumed that the application of barrier creams cannot replace other protective measures and should be maximally used to inhibit low-grade irritants or in combination with other protectants or in body areas where other protective measures are not applicable. [source] Imaging studies of biodistribution and kinetics in drug developmentDRUG DEVELOPMENT RESEARCH, Issue 2 2003Marc S. Berridge Abstract Although the intravenous route of administration is rarely used for drugs, it is by far the most common route for PET and SPECT radiotracers. This article discusses the use of planar and tomographic nuclear medicine technologies to image and quantify the distribution of drugs after local administration. In principle, this would include topical dermatologic, otic, ophthalmic, rectal, and vaginal administration, as well as the intramuscular, oral, and inhalation routes, although precedents do not yet exist for all of these. The studies reviewed focus mainly on oral ingestion and oral and nasal inhalation. The use of nondrug tracers for formulations is discussed, principally with planar imaging or SPECT using radionuclides such as 99mTc, as well as PET imaging where the active ingredient of a formulation can be labeled with 11C or sometimes 18F. An example of the latter type is a study of the deposition and kinetics in the lungs and airways of triamcinolone acetonide, an antiinflammatory steroid used for topical treatment of allergic rhinitis and asthma, dispensed from an inhaler. PET has high potential for evaluation of different formulations and delivery devices in the development of topically applied drugs. Drug Dev. Res. 59:208,226, 2003. © 2003 Wiley-Liss, Inc. [source] Maximizing help for dissonant smokersADDICTION, Issue 1s1 2000Michael Kunze 'Consonant' smokers know and accept the risks associated with tobacco consumption, and do not wish to change their smoking, whereas 'dissonant' smokers are tobacco consumers whose attitudes differ from their behaviour. Dissonant smokers have several options: to quit smoking (the optimal solution), reduce their smoking, switch products or brands, or do nothing. To date, nicotine replacement therapy (NRT) is the best-established medical aid to smoking cessation, but several important factors impact on NRT use. As smokers constitute a diverse group there is a need for various different formulations, some of which will suit certain smokers better than others. Smokers should be allowed to select their preferred products in order to increase compliance, and should also be permitted to combine various products if desired. Adequate dosage regimens should be stressed in order to avoid under-dosing, which is common with NRT. It is also essential that the medical system focuses increasingly on the diagnosis and treatment of those smokers who are unable or unwilling to quit smoking. High nicotine dependence correlates with a high risk of pulmonary and cardiovascular disease; because these smokers cannot quit, cessation efforts have little impact on the incidence of tobacco-related diseases in this population. Additional smoking control interventions, such as smoking reduction therapy, are therefore required to treat this group. Our experience in Vienna shows that these smokers can be targeted through approaches that utilize new messages offering alternatives to cessation. [source] Long-term treatment outcome with different formulations of botulinum toxinEUROPEAN JOURNAL OF NEUROLOGY, Issue 3 2009M. T. Pérez-Saldańa No abstract is available for this article. [source] Influence 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] Zolmitriptan Intranasal: A Review of the Pharmacokinetics and Clinical EfficacyHEADACHE, Issue 1 2006Peter J. Goadsby MD Migraine is a common disabling neurological disorder, associated with headache, nausea, and on occasions vomiting. Zolmitriptan is a widely available serotonin 5HT1B/1D receptor agonist with a long track record in clinical studies and in the treatment of acute migraine. A nasal formulation has been developed that has clear evidence for local absorption, resulting in plasma drug concentrations within 2 minutes of dosing, central nervous system penetration 3 minutes later, and a significant efficacy benefit versus placebo 10 to 15 minutes after dosing. Intranasal zolmitriptan offers advantages to migraineurs, particularly those seeking a more rapid onset of effect without wishing to self-inject, or those with gastrointestinal upset. The comparison of pharmacokinetic and clinical data available from different formulations of zolmitriptan contributes both to the understanding of its mode of action and the characteristics required of an acute migraine treatment if it is to meet patient needs. [source] An in vitro comparison of pH changes in root dentine following canal dressing with calcium hydroxide points and a conventional calcium hydroxide pasteINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2002S. M. Ardeshna Abstract Aim This study aimed to measure and compare pH changes at apical and cervical sites on the external root surface of extracted teeth dressed with calcium hydroxide in two different formulations. Methodology Root canals of 45 single-rooted extracted human teeth were accessed and shaped using a step-down technique with rotary instrumentation. Standard cavities were prepared on the external root surface at specific apical and cervical sites. The teeth were randomly allocated to three groups. Teeth in group A were dressed with calcium hydroxide points, those in group B were dressed with an aqueous calcium hydroxide paste and teeth in group C were left unfilled. Following storage in humid conditions, the pH of the dentine at apical and cervical sites was measured at baseline and then at 24 h, 72 h, 1 week, 10 days, 2 weeks and 3 weeks. Results The pH of the root dentine at both apical and cervical sites was significantly greater (P < 0.001) in teeth dressed with aqueous calcium hydroxide paste compared with those dressed with calcium hydroxide points, when averaged out across all time periods. For all groups, there was a significant difference between the mean apical and cervical pH values for each tooth with lower values for the apical sites (P < 0.001). Conclusion The results of this study indicate that an aqueous calcium hydroxide paste was more effective than calcium hydroxide points at raising the pH on the external root surface of extracted teeth. [source] Indiplon: the development of a novel therapy for the treatment of sleep onset and sleep maintenance insomniaINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2007A. Lankford Summary Indiplon is a novel non-benzodiazepine sedative-hypnotic that modulates the GABAA receptor complex. It appears to be more selective for the ,1-receptor subunit, associated with sedation, than other hypnotics. Two different formulations of indiplon have been developed: an immediate release (IR) version targeting sleep onset insomnia and a modified release (MR) version addressing sleep maintenance insomnia. Early results from clinical trials indicate that both formulations are well tolerated and effective at improving both objective and subjective measures of sleep. As of May 2006 indiplon-IR has been provisionally approved for use in the US market and discussions are continuing with the FDA regarding the MR formulation. [source] Kavut, a traditional Turkish cereal product: production method and some chemical and sensorial propertiesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2006Mehmet Murat Karao Summary Kavut is a cereal-based product made from wholemeal wheat and barley flour, milk or milk powder, fat and sugar. In this study, the best processing method and formulation were investigated by analysing different formulations and processing methods for the kavut. Four different flour combinations (100% wheat without barley, 75% wheat + 25% barley, 50% wheat + 50% barley, 25% wheat + 75% barley), two shortening (butter and margarine) and three different roasting periods (1, 1.5, 2 min) at 250 °C were used in the study. Significant changes were observed in the physical and chemical properties of the cereal by heat treatment in the kavut production. Increase of barley flour in the mixture decreased protein content, softness, altered L colour values, appearance, texture, mouth-feel, and general acceptance and increased ash content, +a and the absorbance value of kavut. While the longer roasting period resulted in reduced softness and colour (L-value) of kavut, roasting period did not significantly affect the general acceptance of kavut. Kavut made from only whole wheatflour was most preferred by the panellists. [source] Full-vectorial to scalar FD-SOR formulations for optical waveguide modelling: a comparative studyINTERNATIONAL JOURNAL OF NUMERICAL MODELLING: ELECTRONIC NETWORKS, DEVICES AND FIELDS, Issue 6 2006D.H. Spadoti Abstract This paper presents a comparative study among three different formulations to analyse optical waveguides. All treatments, namely, full-vectorial, semi-vectorial, and scalar are based on the successive over relaxation-SOR technique. A complete expansion of these three formulations together with a convergence study of the respective iterative relaxation parameters are also provided. Several waveguiding structures are investigated in this work, including D-shaped fibres, rib waveguides, and photonic crystal fibres, addressing the accuracy of the several FD-SOR formulations implemented. It is demonstrated that the semi-vectorial approach produces excellent results when compared to those obtained with the full-vectorial treatment. Copyright © 2006 John Wiley & Sons, Ltd. [source] Water-repellent finishing of cotton fabrics by ultraviolet curingJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008F. Ferrero Abstract Cotton fabrics were water-repellent-finished by radical ultraviolet curing of silicone and urethane acrylates with different formulations. The fabrics were impregnated with undiluted resins and with toluene solutions or water emulsions. Moreover, cationic ultraviolet-curable systems were also investigated, such as an epoxy-functional polysiloxane and mixtures of an epoxy resin with hydroxyl-containing silicone additives. The gel content and polymerization yield were considered for the ultraviolet-curing process evaluation. Water-resistance properties were determined in terms of the contact angle, wettability, moisture adsorption, and water vapor permeability measurements, whereas the morphology and surface composition of treated fabrics were examined with scanning electron microscopy and energy-dispersive X-ray analysis. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] MIXTURES OF BEEF TRIPE, BEEF LIVER AND SOYBEANS APPLIED TO FOOD DEVELOPMENTJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2007L. MALVESTITI ABSTRACT A nutritive sausage-type product was developed with beef tripe, beef liver and soybeans as ingredients. A three-component mixture design was used to obtain seven different formulations (minimum of each main ingredient: 16.5%, maximum: 67.0%). Ingredients were ground, mixed and packed tightly with a polypropylene film to obtain a roll. Pieces were cooked in boiling water for 90 min. The composition of the obtained products varied within the following ranges: proteins 17.32,25.56 g/100 g, lipids 3.22,3.87 g/100 g, crude fiber 1.50,4.50 g/100 g, minerals 1.44,2.72 g/100 g. Total iron levels varied between 1.39 and 2.98 mg/100 g and calcium levels between 15.07 and 34.01 mg/100 g. Surface response analysis was applied to parameters obtained from texture profile analysis (hardness, adhesiveness, cohesiveness and elasticity). Products hardness increased when the soy content increased; on the contrary, formulations enriched in beef tripe were those of higher elasticity and cohesiveness. Color was mainly determined by the incorporation of liver. A nontrained panel was used to evaluate the acceptance of the different formulations. The most accepted one was that with equal proportions of the three main ingredients. Microbiological challenge testing showed that the thermal treatment was enough for assuring the product safeness even in samples with high initial microbial charge. [source] Piecewise linear relaxation of bilinear programs using bivariate partitioningAICHE JOURNAL, Issue 7 2010M. M. Faruque Hasan Abstract Several operational and synthesis problems of practical interest involve bilinear terms. Commercial global solvers such as BARON appear ineffective at solving some of these problems. Although recent literature has shown the potential of piecewise linear relaxation via ab initio partitioning of variables for such problems, several issues such as how many and which variables to partition, which partitioning scheme(s) and relaxation model(s) to use, placement of grid points, etc., need detailed investigation. To this end, we present a detailed numerical comparison of univariate and bivariate partitioning schemes. We compare several models for the two schemes based on different formulations such as incremental cost (IC), convex combination (CC), and special ordered sets (SOS). Our evaluation using four process synthesis problems shows a formulation using SOS1 variables to perform the best for both partitioning schemes. It also points to the potential usefulness of a 2-segment bivariate partitioning scheme for the global optimization of bilinear programs. We also prove some simple results on the number and selection of partitioned variables and the advantage of uniform placement of grid points (identical segment lengths for partitioning). © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Translation of variables and implementation of efficient logic-based techniques in the MINLP process synthesizer MIPSYNAICHE JOURNAL, Issue 11 2009Marcel Ropotar Abstract This article describes alternative GDP formulation and convex hull representations for process synthesis problems and their implementation in a unique MINLP process synthesizer MIPSYN. A special translation of variables in mixed-integer, relaxed, and logic-based variations has been proposed, which enables modeling and solving process alternatives in a narrowed lifted space of variables, defined by nonzero lower and upper bounds. Based on these translation variations, alternative formulations have been developed for convex hulls, multiple-term generalized disjunctive programming problems, and logic-based outer-approximation algorithm, all of them being specialized for the synthesis of process flowsheets. Several studies were performed and three different large-scale synthesis problems were solved to test the performance and efficiency of different formulations. This initial research indicates that the proposed alternative convex hull representation usually outperforms the conventional one when solving both MILP and NLP steps in highly combinatorial MINLP process networks problems. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] New approach to refinery process simulation with adaptive composition representationAICHE JOURNAL, Issue 3 2004Heiko Briesen Abstract The established technique for simulation of refinery processes is the use of pseudocomponents. However, in order to increase the economical benefit of plant operation, it seems inevitable to include molecular information in petroleum mixtures characterization. This will lead to a strong increase of problem size. For this new class of models, there currently seems to be no special algorithms available. The classic pseudocomponent approach is compared with a newly developed solution strategy, which is explicitly developed to efficiently solve simulation problems with a high detail in composition representation. The new solution strategy is an adaptive multigrid method based on a wavelet,Galerkin discretization. With the wavelet,Galerkin discretization the model can easily be formulated on various levels of detail. In an iterative procedure the multigrid concept exploits these different formulations to construct correction-term approximations to the true solution. The discretization of these correction-term models is now done with a detail in composition representation that is determined by a residual-based adaptation strategy. The proposed method has been implemented for a simple 9-stage distillation column and tested for a variety of feed mixtures. In all investigated tests the proposed method proved to be superior to the conventional pseudocomponent approach in terms of accuracy and efficiency. © 2004 American Institute of Chemical Engineers AIChE J, 50: 633,645, 2004 [source] Amphotericin B formulations and drug targetingJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2008J.J. Torrado Abstract Amphotericin B is a low-soluble polyene antibiotic which is able to self-aggregate. The aggregation state can modify its activity and pharmacokinetical characteristics. In spite of its high toxicity it is still widely employed for the treatment of systemic fungal infections and parasitic disease and different formulations are marketed. Some of these formulations, such as liposomal formulations, can be considered as classical examples of drug targeting. The pharmacokinetics, toxicity and activity are clearly dependent on the type of amphotericin B formulation. New drug delivery systems such as liposomes, nanospheres and microspheres can result in higher concentrations of AMB in the liver and spleen, but lower concentrations in kidney and lungs, so decreasing its toxicity. Moreover, the administration of these drug delivery systems can enhance the drug accessibility to organs and tissues (e.g., bone marrow) otherwise inaccessible to the free drug. During the last few years, new AMB formulations (AmBisome®, Abelcet®, and Amphotec®) with an improved efficacy/toxicity ratio have been marketed. This review compares the different formulations of amphotericin B in terms of pharmacokinetics, toxicity and activity and discusses the possible drug targeting effect of some of these new formulations. © 2007 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:2405,2425, 2008 [source] The use of simple dynamic mucosal models and confocal microscopy for the evaluation of lyophilised nasal formulationsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 6 2007Fiona McInnes A range of methods is reported in the literature for assessing hydration and adhesion parameters in the performance of nasal bioadhesive formulations; however, these tests do not always represent the dynamic conditions in the nasal cavity. Lyophilised formulations intended for nasal administration were evaluated using in-vitro tests designed in an attempt to mimic relevant processes in the nasal cavity, and intended to discriminate between different formulations. Initial investigative studies using scanning electron microscopy revealed that the lyophilisate had a highly porous internal structure, expected to provide an ideal porous pathway for re-hydration. Vapour sorption analysis demonstrated substantial weight gain of the lyophilisates on exposure to 95% relative humidity, ranging from 38% to 66%. Agar was used as a synthetic mucosal model designed to provide a standardised quantity of water available for rehydration of the formulations in in-vitro tests. A dynamic adhesion test and a texture analyser sliding test were designed to quantify different aspects of the spreading and adhesion of the hydrating formulations on the synthetic mucosal surface. Examination of the lyophilised formulations using confocal microscopy allowed visualisation and quantification of the initial rate of water ingress into the lyophilisates, which was found to consist of an initial rapid phase, followed by a slower steady-state phase. The results demonstrated that the use of a combination of methods representing the dynamic conditions of the nasal cavity is advisable in order to evaluate a formulation fully and to avoid misleading conclusions. [source] Rheological properties of three different vitamin D ointments and their clinical perception by patients with mild to moderate psoriasisJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 2005JP Marty ABSTRACT Background, Ointments, classically used for the treatment of dermatological diseases, are monophasic viscous semisolid formulations. According to the proportion of their compounds, they have physicochemical and organoleptic properties and when applied on skin show a specific behaviour allowing to be spread more or less easily. Objective, To measure in vitro rheological characteristics of three vitamin D derivative ointments prescribed for the treatment of psoriasis, and to compare their viscosity and clinical acceptability when applied on the diseased skin. Methods, Rheological characteristics of tacalcitol 4 µg/g, calcipotriol 50 µg/g and calcitriol 3 µg/g ointments were assessed by measuring the oscillatory viscoelastic parameters and the permanent flow analysis. Clinical acceptability was studied in 20 psoriatic male or female subjects, aged 18 years or older. A survey evaluated the acceptability of calcitriol vs. tacalcitol and calcipotriol. Questions included information about fluidity, spreading capacity and stickiness after application. Results, We demonstrated that viscoelastic parameters were four times higher for ointment tacalcitol than for calcipotriol and calcitriol, corresponding to a higher consistency of ointment tacalcitol compared to calcipotriol and calcitriol showing both similar results; better fluidity was demonstrated by calcitriol than by tacalcitol and calcipotriol. Comparable results were obtained for the quality to be spread. The sensation of stickiness, significantly different between tacalcitol and calcitriol, was not different between calcipotriol and calcitriol. Conclusion, The above results confirm the relationship between rheological in vitro and sensorial in vivo results: variations between different formulations may have an important influence on non-adherence and treatment failure. [source] Hydrogenated castor oil nanoparticles as carriers for the subcutaneous administration of tilmicosin: in vitro and in vivo studiesJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 2 2009C. HAN Tilmicosin-loaded solid lipid nanoparticles (SLN) were prepared with hydrogenated castor oil (HCO) by o/w emulsion,solvent evaporation technique. The nanoparticle diameters, surface charges, drug loadings and encapsulation efficiencies of different formulations were 90,230 nm, ,6.5,,12.5 mV, 40.3,59.2% and 5.7,11.7% (w/w), respectively. In vitro release studies of the tilmicosin-loaded nanoparticles showed a sustained release and the released tilmicosin had the same antibacterial activity as that of the free drug. Pharmacokinetics study after subcutaneous administration to Balb/c mice demonstrated that a single dose of tilmicosin-loaded nanoparticles resulted in sustained serum drug levels (>0.1 ,g/mL) for 8 days, as compared with only 5 h for the same amount of tilmicosin phosphate solution. The time to maximum concentration (Tmax), half-life of absorption (T˝ ab) and half-life of elimination (T˝ el) of tilmicosin-loaded nanoparticles were much longer than those of tilmicosin phosphate solution. Tissue section showed that drug-loaded nanoparticles caused no inflammation at the injection site. Cytotoxicity study in cell culture and acute toxicity test in mice demonstrated that the nanoparticles had little or no toxicity. The results of this exploratory study suggest that the HCO,SLN could be a useful system for the delivery of tilmicosin by subcutaneous administration. [source] Pharmacokinetics of erythromycin after the administration of intravenous and various oral dosage forms to dogsJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2008G. A. ALBARELLOS The purpose of this study was to describe and compare the pharmacokinetic properties of different formulations of erythromycin in dogs. Erythromycin was administered as lactobionate (10 mg/kg, IV), estolate tablets (25 mg/kg p.o.) and ethylsuccinate tablets or suspension (20 mg/kg p.o.). After intravenous (i.v.) administration, the principal pharmacokinetic parameters were (mean ± SD): AUC(0,,) 4.20 ± 1.66 ,g·h/mL; Cmax 6.64 ± 1.38 ,g/mL; Vz 4.80 ± 0.91 L/kg; Clt 2.64 ± 0.84 L/h·kg; t˝, 1.35 ± 0.40 h and MRT 1.50 ± 0.47 h. After the administration of estolate tablets and ethylsuccinate suspension, the principal pharmacokinetic parameters were (mean ± SD): Cmax, 0.30 ± 0.17 and 0.17 ± 0.09 ,g/mL; tmax, 1.75 ± 0.76 and 0.69 ± 0.30 h; t˝,, 2.92 ± 0.79 and 1.53 ± 1.28 h and MRT, 5.10 ± 1.12 and 2.56 ± 1.77 h, respectively. The administration of erythromycin ethylsuccinate tablets did not produce measurable serum concentrations. Only the i.v. administration rendered serum concentrations above MIC90 = 0.5 ,g/mL for 2 h. However, these results should be cautiously interpreted as tissue erythromycin concentrations have not been measured in this study and, it is recognized that they can reach much higher concentrations than in blood, correlating better with clinical efficacy. [source] Population pharmacokinetics of isoniazid in the treatment of Mycobacterium tuberculosis among Asian and African elephants (Elephas maximus and Loxodonta africana)JOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2005J. N. MASLOW We recently described the clinical presentation and treatment of 18 elephants from six herds infected with TB. Treatment protocols and methods varied between herds to include both oral and rectal dosing using multiple drug doses and formulations. In this paper we present information regarding the pharmacokinetics (PK) of isoniazid (INH) in elephants and provide suggestions regarding initial treatment regimens. Forty-one elephants received INH daily by either oral or rectal administration with different formulations. Population PK analysis was performed using Non-linear Mixed Effect Modeling (NONMEM). Results of oral administration indicated that compared with premixed INH solution, the drug exposure was highest with a suspension prepared freshly with INH powder. When INH was concomitantly given as an admixture over food, Tmax was delayed and variability in drug absorption was significantly increased. Compared with oral administration, similar drug exposures were found when INH was dosed rectally. The data generated suggest that a starting dose of 7.5 mg/kg of INH is appropriate for initial TB treatment in elephants when premixed solution is administered directly into the oropharynx or rectal vault and 4 mg/kg are when INH is administered following immediate suspension from powdered form. [source] Review article: 5-aminosalicylate formulations for the treatment of ulcerative colitis , methods of comparing release rates and delivery of 5-aminosalicylate to the colonic mucosaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2008G. R. LICHTENSTEIN Summary Background, Many oral 5-aminosalicylic acid (5-ASA) formulations are designed to maximize 5-ASA release in the colon where it acts topically on the colonic mucosa. Delayed-release formulations and azo-prodrugs minimize 5-ASA absorption in the upper gastrointestinal (GI) tract. Aims, To review methods for assessing 5-ASA release and colonic distribution from oral formulations, and the potential use of this information for guiding clinical decisions. Methods, PubMed and recent conference abstracts were searched for articles describing techniques used to assess 5-ASA release from ulcerative colitis (UC) therapies. Results, In-vitro GI models, although unable to simulate more complex aspects of GI physiology, can provide useful data on 5-ASA release kinetics and bioaccessibility. Gamma-scintigraphy is useful for investigating GI disintegration of different formulations, but may not accurately reflect 5-ASA distribution. Plasma pharmacokinetic studies provide data on systemic exposure, but not on colonic distribution or mucosal uptake. Mucosal biopsies provide direct evidence of colonic distribution and may predict clinical efficacy, but must be interpreted cautiously because of considerable inter-subject variability and other confounding factors. Conclusion, While assessment of 5-ASA release is important, limitations of individual measurement techniques mean that randomized clinical studies in UC patients remain the best guide for dosing and treatment regimen decisions. [source] Testing Alternative Legal Paradigms: An Experiment in Designing Tax LegislationLAW & SOCIAL INQUIRY, Issue 1 2009Graeme S. Cooper This article reports on empirical research undertaken to test the claim made in a law reform project that citizens could be made more certain of their legal obligations by changing the legal paradigm used to express their rights and obligations. Our research tested a number of hypotheses involving different formulations of the claim being made. We find that the alternative paradigm being presented was inferior to current practice and offer some reasons that would explain our results and the significance of this work for other areas of legal research. [source] Botulinum neurotoxin to treat chronic anal fissure: results of a randomized ,Botox vs.ALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2004Dysport' controlled trial Summary Background :,Botulinum neurotoxin induces healing in patients with idiopathic fissure. The optimal dosage is not well established. Aim :,To compare the efficacy and tolerability of two different formulations of type A botulinum neurotoxin, and to provide more evidence with regard to the choice of dosage regimens. Methods :,Symptomatic adults with chronic anal fissure were enrolled in a randomized study. The outcome of each group was evaluated clinically, and by comparing the pressure of the anal sphincters before and after treatment. Results :,Fifty patients received injections of 50 units of Botox formulation (group I), and 50 patients received injections of 150 units of Dysport toxin (group II). One month after injection, 11 patients in group I and eight in group II had mild incontinence of flatus. At the 2-month evaluation point, 46 patients in group I and 47 patients in group II had a healing scar. In group I patients, the mean resting anal pressure was 41.8% lower, and the maximum voluntary squeeze pressure was 20.2% lower, than the baseline value. In group II patients, the resting anal pressure and maximum voluntary squeeze pressure were 60.0 ± 12.0 mmHg and 71.0 ± 30.0 mmHg, respectively. There were no relapses during an average of about 21 months of follow-up. Conclusions :,Botulinum neurotoxin may be considered an effective treatment in patients with chronic anal fissure. The efficacy and tolerability of the two different formulations of botulinum neurotoxin were indistinguishable. [source] An asymptotic-induced one-dimensional model to describe fires in tunnels II: the stationary problemMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 15 2003Ingenuin Gasser Abstract We study stationary solutions of a one-dimensional low-Mach-number model derived in Gasser and Struckmeier (Math. Meth. Appl. Sci. 2002; 25(14): 1231) to describe fire events in long tunnels. The existence of solutions of the corresponding stationary model is shown to be equivalent to the existence of solutions of an algebraic problem. Multiple solutions are shown to be possible. The relation between different formulations of the problem is analysed. Weak and special distributional solutions are considered. Finally, numerical examples of realistic tunnel data with single and multiple solutions of the stationary problem are given. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||