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Active Substances (active + substance)
Selected AbstractsRainwater Dissolved Organic Carbon: Characterization of Surface Active Substances by Electrochemical MethodELECTROANALYSIS, Issue 19-20 2007osovi Abstract Surface active substances as organic constituents of bulk precipitation were studied by AC voltammetric method. Adsorption characteristics at the mercury electrode of real rainwater samples are compared with aqueous solutions of a number model substances suggested to be representative of water soluble organic compounds (WSOC) in atmospheric aerosols and droplets: monocarboxylic, dicarboxylic, and polyacidic compounds, levoglucosan, polyaromatic hydrocarbon naphtalene and anionic surfactant sodium dodecylbenzene sulfonate. On the basis of the capacitance vs. potential curves and the surfactant activity normalized to the organic carbon content it is concluded that humic like substances, monocarboxylic acids and polyaromatic hydrocarbons may play an important role in atmospheric aquatic system because of their surface active potential. [source] 3-Bromo-4-(1H-3-indolyl)-2,5-dihydro-1H-2,5-pyrroledione Derivatives as New Lead Compounds for Antibacterially Active Substances.CHEMINFORM, Issue 31 2006Siavosh Mahboobi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Limited LCAs of pharmaceutical products: merits and limitations of an environmental management toolCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 2 2003Anne Marie de Jonge This article explores both the merits and the limitations of life cycle analysis (LCA) as an environmental management tool in the framework of the pharmaceutical industry. In this study, limited LCAs in the form of product lifecycle-oriented energy balances were established for two rather different pharmaceutical products. Primary energy requirements served as the single indicator for the products' direct and indirect environmental impacts. The functional units of the products were defined as the one year treatments of average patients. The results of the case studies indicate that the portion of the active substance in the pharmaceutical end product is an important predictor for the breakdown of energy requirements and thus environmental impacts over the life cycle. Despite its limitations, the energy balances provide first-hand indications of where eco-efficiency measures should be taken. In this sense, the limited LCAs served as a useful environmental management tool. Copyright © 2003 John Wiley & Sons, Ltd. and ERP Environment [source] Measurement of blood clearance time by Limulus G test of Candida -water soluble polysaccharide fraction, CAWS, in miceFEMS IMMUNOLOGY & MEDICAL MICROBIOLOGY, Issue 1 2000Kiyoshi Kurihara Abstract The Limulus G test, responsive to ,-1,3- d -glucan, is a well-established method for the detection of invasive fungal infection. We have recently found that Candida albicans released a water-soluble polysaccharide fraction (CAWS) into synthetic medium (Uchiyama et al., FEMS Immunol. Med. Microbiol. 24 (1999) 411,420). CAWS was composed of a mannoprotein-,-glucan complex and activated Limulus factor G, and thus would be similar to the Limulus active substance in patient's blood. In a preliminary investigation, we have found that CAWS is lethal when administered intravenously in a murine system. In this study, we examined the toxicity and then the fate of CAWS in mice. The lethal toxicity was strain-dependent and strain DBA/2 was the most resistant. The toxicity was, at least in part, reduced by salbutamol sulfate and prednisolone treatment in the sensitive strains. On intravenous administration, the half clearance time (t1/2) was approximately 40 min in mice (DBA/2). On intraperitoneal administration, CAWS appeared in the blood with a peak concentration at 1 h. In order to establish a treatment plan, it is important to demonstrate the onset and the termination of deep-seated mycosis. The Limulus G test is suitable for the above purpose; however, it is necessary to fully understand the fate of ,-1,3- d -glucan in patients' blood [source] Medicinal plants in Suriname: hypotensive effect of Gossypium barbadenseJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 3 2004J. A. Hasrat ABSTRACT In traditional medicine Gossypium barbadense L. is used against hypertension. Looking for a scientific basis for this use, the blood-pressure-lowering effect of the decoction of the leaves was confirmed. Fraction II (frII) of the crude extract of G. barbadense showed a dose-dependent hypotensive effect in anaesthetized rats. In hexamethonium-treated rats, the blood-pressure-lowering effect of frII was almost abolished. A small decrease of the blood-pressure-lowering effect was followed by an increase in the blood pressure. Phentolamine antagonized the increase in blood pressure in hexamethoniumtreated rats. High doses of atropine (4 mg/rat) suppressed both depressor and heart effects. In-vitro experiments revealed that atropine did not antagonize the contraction of the ileum of the rat. Tripelennamine in a concentration of 100 ,g could not influence the contraction either, whereas 300 ,g did. In the guinea-pig ileum 10 ,g tripelennamine did not reduce the contraction significantly. In the mechanism of action of frII, acetylcholine receptors could be involved, but not histaminergic or adrenergic receptors. Although it is still not known which compound(s) in G. barbadense is (are) the active substance(s), the results obtained may explain the use of this plant in traditional medicine in Suriname. [source] Absence of mutagenic effects of a particular Symphytum officinale L. liquid extract in the bacterial reverse mutation assayPHYTOTHERAPY RESEARCH, Issue 3 2010Birgit Benedek Abstract Comfrey (Symphytum officinale L.) root is traditionally used for the topical treatment of contusions, strains and sprains. Besides allantoin and rosmarinic acid, which are discussed as pharmacologically active principles, the drug contains pyrrolizidine alkaloids (PAs) known for their hepatotoxic, carcinogenic and mutagenic properties. The topical herbal medicinal products Kytta-Salbe® f and Kytta-Plasma® f contain a PA-free liquid extract from comfrey root as active substance. The aim of this study was to demonstrate the absence of genotoxic effects of this special extract in the bacterial reverse mutation assay (Ames test). Briefly, comfrey root liquid extract was investigated for its ability to induce gene mutations in Salmonella typhimurium strains TA 98, TA 100, TA 102, TA 1535 and TA 1537 with and without metabolic activation using the mammalian microsomal fraction S9 mix. Reference mutagens were used to check the validity of the experiments. Comfrey root fluid extract showed no biologically relevant increases in revertant colony numbers of any of the five tester strains, neither in the presence nor in the absence of metabolic activation. In conclusion, the comfrey root fluid extract contained in Kytta-Salbe® f and Kytta-Plasma® f was not mutagenic in the bacterial reverse mutation assay. Copyright © 2009 John Wiley & Sons, Ltd. [source] Enhanced pro-apoptotic and anti-adipogenic effects of genistein plus guggulsterone in 3T3-L1 adipocytesBIOFACTORS, Issue 3 2007Jeong-Yeh Yang Abstract Genistein (G), an isoflavone, and guggulsterone (GS), the active substance in guggulipid, have been reported to possess therapeutic effects for obesity. In the present study, we investigated the effects of combinations of G plus GS on apoptosis and adipogenesis in 3T3-L1 cells. In mature adipocytes, G and GS individually caused apoptosis, but combination of G plus GS significantly increased apoptosis, more than either compound alone. Furthermore, G plus GS caused a greater increase in procaspase-3 cleavage, Bax expression, cytochrome c release, and proteolytic cleavage of PARP than either compound alone. In maturing preadipocytes G and GS each suppressed lipid accumulation, but the combination potentiated the inhibition of lipid accumulation. These results suggest that combination of genistein and guggulsterone may exert anti-obesity effects by inhibiting adipogenesis and inducing apoptosis in adipocytes. [source] A method for lipase co-precipitation in a biodegradable protein matrixBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2007M. Golubovic Abstract This article presents a novel method for immobilization of active ingredients. The method is based on CO2 aided active ingredient co-precipitation with glycinin, a biodegradable protein matrix from edible soybean protein. Glycinin precipitates abundantly under isoelectric conditions and serves as the matrix within which the active substance is trapped during the precipitation process. The enzyme lipase from Candida rugosa was successfully co-precipitated into the protein pellet to prove the principle. It was shown that the lipase within the co-precipitate retained lipase and esterase activity under different pH conditions. In some cases the activity was even higher than the activity of crude lipase, possibly due to the protective role of the matrix protein. Due to the retained lipase activity and food-grade quality of the binary precipitate, it has potential of being used in the food or pharmaceutical industry. Additional quality of the binary precipitate is the potentially significantly reduced downstream processing due to the fact that no organic solvents or precipitants were used in the precipitation process. Biotechnol. Bioeng. 2007;98: 1209,1218. © 2007 Wiley Periodicals, Inc. [source] Rainwater Dissolved Organic Carbon: Characterization of Surface Active Substances by Electrochemical MethodELECTROANALYSIS, Issue 19-20 2007osovi Abstract Surface active substances as organic constituents of bulk precipitation were studied by AC voltammetric method. Adsorption characteristics at the mercury electrode of real rainwater samples are compared with aqueous solutions of a number model substances suggested to be representative of water soluble organic compounds (WSOC) in atmospheric aerosols and droplets: monocarboxylic, dicarboxylic, and polyacidic compounds, levoglucosan, polyaromatic hydrocarbon naphtalene and anionic surfactant sodium dodecylbenzene sulfonate. On the basis of the capacitance vs. potential curves and the surfactant activity normalized to the organic carbon content it is concluded that humic like substances, monocarboxylic acids and polyaromatic hydrocarbons may play an important role in atmospheric aquatic system because of their surface active potential. [source] Construction and Evaluation of a Gold Tubular Electrode for Flow Analysis: Application to Speciation of Antimony in Water SamplesELECTROANALYSIS, Issue 6 2007Rodrigo Santos Abstract A tubular gold electrode (TGE) is described for the first time by summarizing the important aspects of its construction and evaluation. Applicability of the TGE is evaluated in the speciation of Sb(III) and Sb(V) using anodic stripping voltammetry in a single flow manifold. Studies with surface active interferences and metallic cations were performed. The proposed conditions for antimony determination showed good tolerance towards cationic, anionic and nonionic surface active substances. A linear response for antimony was obtained for solutions containing significant amounts of several metallic cations. Linear calibration curves for Sb(III) were obtained in the range 1,10,ppb with a detection limit of 0.19,ppb (CV=2.91%, n=5, [Sb(III)]=5,ppb). For Sb(V), linear calibration curves were in the range 1,15,ppb with a detection limit of 0.32,ppb (CV=1.41%, n=5, [Sb(V)]=5,ppb). The figures of merit achieved sustain for the good applicability of the proposed method as it allows the determination of antimony at levels below maximum values permitted in consuming waters. Results of antimony concentration determined in water samples were validated against the ICP-MS reference procedure or compared with reference water samples. [source] Proteomics of snake venoms from Elapidae and Viperidae families by multidimensional chromatographic methodsELECTROPHORESIS, Issue 16 2003Jiraporn Nawarak Abstract Snake venoms contain a large number of biologically active substances and the venom components are very useful for pharmaceutical applications. Our goal is to separate and identify components of snake venoms in ten snake species from the Elapidae and Viperidae families using multidimensional chromatographic methods. The multidimensional chromatographic methods include reversed-phase high-performance liquid chromatography (RP-HPLC), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), lab-on-a-chip, two-dimensional electrophoresis (2-DE), and mass spectrometry. The venoms of eight snake species demonstrated major differences in hydrophobicity, molecular weight separations, and 2-DE protein distribution patterns. The 2-DE images showed major differences between families, within each family and even between the same species. Venoms of the Elapidae family showed many basic proteins with a wide range of molecular weights, while venoms of the Viperidae family showed wide ranges of pI and molecular weights, especially for Trimeresurus sp. The multidimensional chromatographic methods revealed specific differences in venom proteins intra-species as well as between species and families. We have isolated and identified proteins that may be unique for each species for further studies in the proteome of snake venoms and their potentially use in the pharmaceutical applications. [source] Altered reproduction in fish exposed to pulp and paper mill effluents: Roles of individual compounds and mill operating conditionsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2008L. Mark Hewitt Abstract For the last 20 years, studies conducted in North America, Scandinavia, and New Zealand have shown that pulp and paper mill effluents affect fish reproduction. Despite the level of effort applied, few leads are available regarding the factors responsible. Effluents affect reproduction in multiple fish species, as evidenced by decreased gonad size, decreased circulating and gonadal production of reproductive steroids, altered expression of secondary sex characteristics, and decreased egg production. Several studies also have shown that effluent constituents are capable of accumulating in fish and binding to sex steroid receptors/binding proteins. Studies aimed at isolating biologically active substances within the pulping and papermaking process have provided clues about their source, and work has progressed in identifying opportunities for in-mill treatment technologies. Following comparisons of manufacturing processes and fish responses before and after process changes, it can be concluded that effluent from all types of mill processes are capable of affecting fish reproduction and that any improvements could not be attributed to a specific process modification (because mills normally performed multiple modifications simultaneously). Improved reproductive performance in fish generally was associated with reduced use of molecular chlorine, improved condensate handling, and liquor spill control. Effluent biotreatment has been effective in reducing some effects, but biotreated effluents also have shown no difference or an exacerbation of effects. The role of biotreatment in relation to effects on fish reproduction remains unclear and needs to be resolved. [source] Summary of findings from a participant country pollen beetle questionnaireEPPO BULLETIN, Issue 1 2008D. M. Richardson A questionnaire was sent to all participating countries to gain some background information on rape growing and on pollen beetle (Meligethes aeneus). Information was sought on the use of thresholds, the availability of active substances and on the year in which resistance, if present, had been observed. A summary of the main findings of the questionnaire are presented. In total 20 countries responded and resistance in pollen beetle was reported in 12 of those countries. Information presented shows the range of active substances and doses recommended, frequency of use of insecticides on rape, and year when resistance was reported. [source] Different methods of monitoring susceptibility of oilseed rape beetles to insecticidesEPPO BULLETIN, Issue 1 2008T. Thieme The resistance of oilseed rape pollen beetles to lambda-cyhalothrin has increased in Germany over the period 2002 to 2007. Oilseed rape pollen beetles are very good at dispersing, therefore field results should always be compared with those of laboratory experiments. The response of oilseed rape pollen beetles to active substances may not be the same as that to formulated products. Bioassays in which beetles are exposed to insecticides on either complete inflorescences or flower buds give different results. It is evident that samples of the genus Meligethes collected in the field can include several different species. Monitoring for insecticide resistance should be done using only the true oilseed rape pollen beetle. [source] Decision support systems used in the Netherlands for reduction in the input of active substances in agricultureEPPO BULLETIN, Issue 3 2003E. Bouma Since the middle of the 1980s, Dutch farmers have been using decision support systems (DSS) as an aid in the control of pests. This started with EPIPRE, then weather-related potato blight warning systems were developed (Prophy and Plant-Plus). In the 1990s, many weather-based DSS were developed against pests of orchards, flower bulbs, arable crops and field-produced vegetables. Also, a DSS was developed to predict and check the effect of meteorological conditions on the effectiveness of application timing of plant protection products (GEWIS). The use of these systems resulted in more sustainable crop protection: sustainable because the use of DSS led to a lower risk of crop damage and, in many cases, to a lower input of active substances, by optimization of the product and dose to actual phytosanitary and meteorological conditions. The use of GEWIS to ensure application at the right time of day further reduced the input of active substances and increased efficacy. [source] Towards the Synthesis of Highly Functionalized Chiral ,-Amino Nitriles by Aminative Cyanation and Their Synthetic ApplicationsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2006Luca Bernardi Abstract The cyanobis(dibenzylamino)borane-mediated transformation of chiral aldehydes into the corresponding ,-amino nitriles is described. Starting from these compounds short synthetic routes can be envisaged for obtaining diastereomerically pure functionalized 1,2-diamines and hydroxylated ,-amino acids that are of interest as core key units of biologically active substances or as potential ligands for asymmetric catalysis. The stereochemical outcome of the aminative cyanation reaction is discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Antioxidant polyphenols from the mycelial culture of the medicinal fungi Inonotus xeranticus and Phellinus linteusJOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2008J.-Y. Jung Abstract Aims:, The medicinal fungi Inonotus xeranticus and Phellinus linteus in the family Hymenochaetaceae have been used as traditional medicines for the treatment of various diseases. However, the compound responsible for the antioxidant activity is still unknown. Therefore, this study was conducted to characterize the antioxidant substances present in cultured broths made from these fungi. Methods and Results:, Antioxidant fractions of the cultured broths obtained from I. xeranticus and P. linteus were analysed using reversed-phase HPLC, which revealed several peaks that exhibited a potent free radical scavenging activity. To identify these antioxidant peaks, an I. xeranticus strain was mass-cultured, and the cultured broth was separated using antioxidant activity-guided fractionation. Four major active substances were purified and identified as hispidin and its dimers, 3,14,-bihispidinyl, hypholomine B, and 1,1-distyrylpyrylethan based on spectroscopic analyses. All compounds exhibited a significant scavenging activity against these radical species in a concentration-dependent manner. Conclusions:, Antioxidant substances found in the cultured broths of the medicinal fungi I. xeranticus and P. linteus were identified as hispidin and its dimers, 3,14,-bihispidinyl, hypholomine B, and 1,1-distyrylpyrylethan. Significance and Impact of the Study:, Polyphenol antioxidants were isolated from the cultured broth of the medicinal fungi I. xeranticus and P. linteus and identified based on extensive spectroscopic analyses. These compounds exhibited a strong antioxidant activity. [source] Rapid bioconcentration of steroids in the plasma of three-spined stickleback Gasterosteus aculeatus exposed to waterborne testosterone and 17,-oestradiolJOURNAL OF FISH BIOLOGY, Issue 3 2007R. J. Maunder The relationship over time between the concentrations of two steroids, singly and in combination, in a static exposure system and in the blood of three-spined stickleback Gasterosteus aculeatus, held within the exposure system was investigated. Groups of three-spined stickleback were exposed (nominally) to either 1000 ng l,1 17,-oestradiol (E2), testosterone (T) or E2 and T in combination at the same concentrations for 6 days. Both water and fish were sampled at intervals and steroid concentrations in both compartments were determined. The plasma steroid time profile revealed a rapid bioconcentration within the first 6 h of exposure. The plasma steroid levels attained at this time point (20,90 ng ml,1) were up to 50-fold (E2) and 200-fold (T) greater than the actual levels of steroid measured in the exposure water, while levels in the blood of control fish did not exceed 4 ng ml,1. The substantial elevation of plasma steroid levels relative to the concentrations of steroid to which the fish were exposed in the ambient water gives scope for delivery of the steroids to target endocrine tissues at levels far in excess of what might be predicted on the basis of passive branchial uptake alone. These results are discussed in relation to endocrine disruption, and in particular the occurrence of effects in fish exposed to levels of endocrine active substances that are seemingly physiologically irrelevant. [source] Glutamate Fermentation By-product Activates Plant Defence Responses and Confers Resistance Against Pathogen InfectionJOURNAL OF PHYTOPATHOLOGY, Issue 10 2010Daisuke Igarashi Abstract In the food industry, glutamate fermentation by-product (GFB) is generated by purifying glutamate products from microbial fermentation. The potential applications of GFB for upgrading agricultural soil, for foliar fertility, and as plant plankton for shrimp have been studied. We examined the efficacy of GFB foliar application and determined that GFB treatment increased the resistance of Arabidopsis leaves to infection by bacterial pathogens. Microarray gene expression analysis of Arabidopsis leaves after treatment with GFB indicated that the expression of plant defence-related genes increased. In Corynebacterium fermentation, the active substances for induction of the defence response were extracted or solubilized after treatment with heating under acidic conditions. This extract was also effective in strawberry and grape leaves for the induction of hydrogen peroxide production. These findings suggest that foliar application of GFB that contains elicitor molecules derived from fermentation bacteria is useful for plant protection in agricultural fields. [source] Applications of Raman spectroscopy to pharmacyJOURNAL OF RAMAN SPECTROSCOPY, Issue 5 2004Giancarlo Fini Abstract This paper gives a summary of this special issue on ,Pharmaceutical Applications of Raman Spectroscopy'. It summarizes the papers collected and introduces the possible applications of classical Raman spectroscopy (macro and micro) and surface-enhanced Raman spectroscopy to the identification of pharmacologically active substances, their qualitative and quantitative analysis, characterization of crystalline forms and structure determination. Copyright © 2004 John Wiley & Sons, Ltd. [source] Peak shape improvement of basic analytes in capillary liquid chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 3 2005Anja Prüß Abstract The analysis of bases is of special interest in pharmaceutical research because numerous active substances contain basic functional groups. Capillary and conventional size LC separations of drug substances spiked with potential impurities were compared. In the case of the nonpolar drug levonorgestrel equal separation efficiency was readily attained by both techniques. The peaks of basic substances, however, showed extensive tailing when separated by capillary LC. The peak deformation was attributable to interactions of the basic substances with the polar inner surface of the fused silica capillaries employed in capillary LC and does not appear with the steel tubing generally used in conventional size LC. This drawback of capillary LC was overcome by use of deactivated fused silica capillaries for column hardware and transfer lines. [source] Loading of Bacterial Cellulose Aerogels with Bioactive Compounds by Antisolvent Precipitation with Supercritical Carbon DioxideMACROMOLECULAR SYMPOSIA, Issue 2 2010Emmerich Haimer Abstract Bacterial cellulose aerogels overcome the drawback of shrinking during preparation by drying with supercritical CO2. Thus, the pore network of these gels is fully accessible. These materials can be fully rewetted to 100% of its initial water content, without collapsing of the structure due to surface tension of the rewetting solvent. This rehydration property and the high pore volume of these material rendered bacterial cellulose aerogels very interesting as controlled release matrices. Supercritical CO2 drying, the method of choice for aerogel preparation, can simultaneously be used to precipitate solutes within the cellulose matrix and thus to load bacterial cellulose aerogels with active substances. This process, frequently termed supercritical antisolvent precipitation, is able to perform production of the actual aerogel and its loading in one single preparation step. In this work, the loading of a bacterial cellulose aerogel matrix with two model substances, namely dexpanthenol and L-ascorbic acid, and the release behavior from the matrix were studied. A mathematical release model was applied to model the interactions between the solutes and the cellulose matrix. The bacterial cellulose aerogels were easily equipped with the reagents by supercritical antisolvent precipitation. Loading isotherms as well as release kinetics indicated no specific interaction between matrix and loaded substances. Hence, loading and release can be controlled and predicted just by varying the thickness of the gel and the solute concentration in the loading bath. [source] Toward an "omic" physiopathology of reactive chemicals: Thirty years of mass spectrometric study of the protein adducts with endogenous and xenobiotic compoundsMASS SPECTROMETRY REVIEWS, Issue 5 2009Federico Maria Rubino Abstract Cancer and degenerative diseases are major causes of morbidity and death, derived from the permanent modification of key biopolymers such as DNA and regulatory proteins by usually smaller, reactive molecules, present in the environment or generated from endogenous and xenobiotic components by the body's own biochemical mechanisms (molecular adducts). In particular, protein adducts with organic electrophiles have been studied for more than 30 [see, e.g., Calleman et al., 1978] years essentially for three purposes: (a) as passive monitors of the mean level of individual exposure to specific chemicals, either endogenously present in the human body or to which the subject is exposed through food or environmental contamination; (b) as quantitative indicators of the mean extent of the individual metabolic processing which converts a non-reactive chemical substance into its toxic products able to damage DNA (en route to cancer induction through genotoxic mechanisms) or key proteins (as in the case of several drugs, pesticides or otherwise biologically active substances); (c) to relate the extent of protein modification to that of biological function impairment (such as enzyme inhibition) finally causing the specific health damage. This review describes the role that contemporary mass spectrometry-based approaches employed in the qualitative and quantitative study of protein,electrophile adducts play in the discovery of the (bio)chemical mechanisms of toxic substances and highlights the future directions of research in this field. A particular emphasis is given to the measurement of often high levels of the protein adducts of several industrial and environmental pollutants in unexposed human populations, a phenomenon which highlights the possibility that a number of small organic molecules are generated in the human organism through minor metabolic processes, the imbalance of which may be the cause of "spontaneous" cases of cancer and of other degenerative diseases of still uncharacterized etiology. With all this in mind, it is foreseen that a holistic description of cellular functions will take advantage of new analytical methods based on time-integrated metabolomic measurements of a new biological compartment, the "adductome," aimed at better understanding integrated organism response to environmental and endogenous stressors. © 2009 Wiley Periodicals, Inc., Mass Spec Rev 28:725,784, 2009 [source] Release of potassium sorbate from active films of sodium alginate crosslinked with calcium chloridePACKAGING TECHNOLOGY AND SCIENCE, Issue 6 2009E. M. Zactiti Abstract The release of potassium sorbate from alginate films was evaluated considering different active agent concentrations in the film and three levels of alginate crosslinking. The mechanism involved in the diffusional process was investigated using the Power Law Model. The results indicated that potassium sorbate diffusion in alginate films has characteristics of Fickian and non-Fickian behaviour. Effective diffusion coefficients obtained using the solution in series derived from Fick's Second Law are close to values obtained by the short-time solution, indicating that the influence of swelling on effective diffusivity, although perceptible, is small, allowing the use of an average effective diffusivity. The values of effective diffusivity found indicate that alginate films have a potential use as systems for release of active substances. Copyright © 2009 John Wiley & Sons, Ltd. [source] Multivariate analysis of toxicological and environmental properties of soil nematicidesPEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 1 2009Sara Sánchez-Moreno Abstract BACKGROUND: In intensive agriculture, the use of pesticides and soil fumigants is necessary to produce economically viable crops worldwide. However, this practice may involve undesirable effects on human health and the environment. In 1995, methyl bromide was restricted by the Montreal Protocol because of possible ozone depletion. The objective of this study was to compare intrinsic environmental and toxicological properties of 11 active substances with nematicidal properties, some of them recognized as methyl bromide alternatives. RESULTS: Four groups of active substances were discriminated by a series of principal component analyses (PCAs): (a) high toxicity to non-target fauna, humans and animals and medium persistence in the environment (cadusafos, ethoprophos and fenamiphos); (b) high toxicity to humans, animals and non-target fauna and high persistence (carbofuran and fosthiazate); (c) low toxicity to non-target fauna, humans and animals and low persistence (carbosulfan, benfuracarb and oxamyl); (d) low toxicity to humans, animals and non-target fauna and medium persistence in the environment (1,3-dichloropropene, chloropicrin and methyl bromide). CONCLUSION: Evaluating the multiple aspects of toxicological and environmental properties of active substances through PCA is proposed as a helpful tool for initially comparing the complex toxicological behaviour of active substances as plant protection products. Copyright © 2008 Society of Chemical Industry [source] Fluorescence Kinetics of Protoporphyrin-IX Induced from 5-ALA Compounds in Rabbit Postballoon Injury Model for ALA-PhotoangioplastyPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 5 2008Oh-Choon Kwon Protoporphyrin IX (PpIX) is one of the photodynamically active substances that are endogenously synthesized in the metabolic pathway for heme as a precursor. Aminolevulinic acid-esters are more lipophilic than conventional 5-aminolevulinic acid (ALA) and some of them are currently being approved as new drugs for photodynamic diagnosis (PDD) and photodynamic therapy (PDT). In order to investigate the pharmacokinetics of ALA and ALA-ethyl ester (ALA-ethyl) in the atheromatous plaque and normal aortic wall of rabbit postballoon injured artery, each 60 mg kg,1 of ALA or ALA-ethyl was injected intravenously followed by serial detection of PpIX fluorescence of harvested arteries at 0,48 h post-injection. Maximum PpIX build-up in the atheromatous plaque was seen at 2 h after injecting ALA. In contrast, it occurred at 9 h after injecting ALA-ethyl. In addition, the selective build-up of ALA in the atheromatous plaque compared to normal vessel wall was much higher (10 times) than that of ALA-ethyl. The time of maximum fluorescence intensity of PpIX was employed as drug-light-interval for subsequent PDT treatment of the atheromatous plaque with 50,150 J cm,1 of light dose. Significant reduction in plaque was observed without damage of the medial wall at both groups, but smooth muscle cell (SMC) was still present in the media region below the PDT-treated atheromatous plaque. In conclusion, ALA may be a more effective compound for endovascular PDT treatment of the atheromatous plaque compared with ALA-ethyl based on their pharmacokinetics, but further optimization of PDT methodology remains to remove completely residual SMC in the media for preventing potential restenosis. [source] Cyclitols and carbohydrates in leaves and roots of 13 Eucalyptus species suggest contrasting physiological responses to water deficitPLANT CELL & ENVIRONMENT, Issue 11 2006ANDREW MERCHANT ABSTRACT In many tree species, physiological adaptations to drought include the accumulation of osmotically active substances and/or the presence of particular compatible solutes, among them cyclitols. Recently, the cyclitol quercitol was identified in species of Eucalyptus, a diverse genus whose speciation is probably driven by adaptation to water availability. We subjected seedlings of 13 Eucalyptus species from different ecosystems (,mesic' and ,xeric') and different sub-generic taxonomic groups to 10 weeks of water deficit (WD) treatment. Pre-dawn water potentials (,pdwn) and relative water content (RWC) were determined in shoots, and total osmolality, soluble low-molecular-weight carbohydrates and cyclitols were measured in leaves and roots. Responses to water deficit followed two distinct patterns: Eucalyptus species from ,mesic' environments adjusted concentrations of sucrose (through increased levels of sucrose and decreases in RWC) in response to water deficit, whereas ,xeric' species increased concentrations of quercitol (through reductions in RWC). In root tissues, only species from xeric environments contained high levels of quercitol and mannitol, increasing under WD conditions. We suggest that the former (mesic) strategy may be beneficial to respond to short-lasting drought conditions, because sucrose is easily metabolized, whereas the latter (xeric) strategy may relate to an effective acclimation to longer-lasting drought. These physiological response groups are also related to taxonomic groups within the genus. [source] Slow-release nanoparticle-encapsulated delivery system for laryngeal injection,THE LARYNGOSCOPE, Issue 5 2010Vasantha L. Kolachala PhD Abstract Objectives/Hypothesis: There is a need for a slow-release system for local delivery of therapeutics to the larynx. Most therapeutic substances, such as steroids or chemotherapeutic agents that are injected into the larynx are cleared rapidly. Repeated laryngeal injection of these substances at short intervals is impractical. Injectable encapsulated poly(lactide-co-glycolide) (PLGA) nanoparticles offer a potential slow-release delivery system for biologically active substances in the larynx. Study Design: Controlled animal study. Methods: PLGA nanoparticles were fabricated using a double emulsion method and were loaded with Texas Red-dextran (NPTR), hepatocyte growth factor (NPHGF), and bovine serum albumin (NPBSA). In vitro release of NPTR, NPBSA, and NPHGF was determined over approximately 2 weeks to assess potential duration of PLGA nanoparticle delivery. In vivo release of NPTR was assessed in a murine vocal fold injection model. The transcriptional effect of NPHGF on procollagen was measured in vitro to assess whether released growth factor retained functionality. Results: In vitro release kinetics demonstrated slow release of NPTR, NPBSA, and NPHGF over 12 to 14 days. In vitro NPTR release correlated with in vivo results. In vivo presence of NPTR occurred up to 7 days compared to 1 day for Texas Red control. In addition, NPHGF ameliorated transforming growth factor-, induced procollagen in vitro in 3T3 fibroblast cells. Conclusions: The results demonstrate the potential utility of nanoparticle encapsulation as an effective method for long-term delivery of specific drugs and biologically active substances to the larynx. Laryngoscope, 2010 [source] A model of the effect of fungicides on disease-induced yield loss, for use in wheat disease management decision support systemsANNALS OF APPLIED BIOLOGY, Issue 1 2007A. Milne Abstract A model of the effect of foliar-applied fungicides on disease-induced yield loss is described, parameterised and tested. The effects of fungicides on epidemics of Septoria tritici (leaf blotch), Puccinia striiformis (yellow rust), Blumeria graminis f.sp. tritici (powdery mildew) and Puccinia triticina (brown rust) on winter wheat were simulated using dose,response curve parameters. Where two or more active substances were applied together, their joint action was estimated using an additive dose model where the active substances had the same mode of action or a multiplicative survival model where the modes of action differed. By coupling the model with models of wheat canopy growth and foliar disease published previously, it was possible to estimate disease-induced yield loss for a prescribed fungicide programme. The difference in green canopy area and, hence, interception of photosynthetically active radiation between simulated undiseased and diseased (but treated) crop canopies was used to estimate yield loss. The model was tested against data from field experiments across a range of sites, seasons and wheat cultivars and was shown to predict the observed disease-induced yield loss with sufficient accuracy to support fungicide treatment decisions. A simple method of accounting for uncertainty in the predictions of yield loss is described. Fungicide product, dose and spray timing combinations selected using the coupled models responded appropriately to disease pressure and cultivar disease resistance. [source] Cytokine response of electrolytic ablation in an ex vivo perfused liver modelANZ JOURNAL OF SURGERY, Issue 7-8 2010Gianpiero Gravante Abstract Background:, The inflammatory response following hepatic ablation depends on different factors including the method used, the duration and intensity of the treatment and the presence or absence of ischemia. Debate continues about the use of different modalities and whether some aspects of the response may be advantageous by releasing immunological active substances. Little data have been published concerning the cytokine response elicited by hepatic electrolytic ablation (EA). Study of an ex vivo liver model could allow for the evaluation of this response without the influence of confounding systemic factors. Methods:, Livers explanted from 11 pigs were perfused extracorporeally with normothermic autologous blood. Four of them underwent EA after 1 h of reperfusion. Serum samples were obtained up to 6 h after the reperfusion and assayed for IL-1,, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IFN-,, TNF-,. Results:, Significant changes in the control group were observed for IL-6 after the second hour and IL-8 after the first hour compared with baseline levels (P < 0.001). In the EA group, IL-6 and IL-12 were raised after the second hour and IL-8 and IL-10 after the first hour (P < 0.001). The comparison between groups showed significant differences for IL-2, IL-4 (decreased in the EA group compared with controls), IL-10 and TNF-, (EA group increased compared with controls; P < 0.001). Conclusions:, The ex vivo perfused liver model demonstrated changes in levels of IL-2, IL-4, IL-10 and TNF-, following hepatic EA. [source] | |||||||||||||||||||||||||||||||