982 resultados para Kalanchoe brasiliensis. Coirama branca. Saião. HPLC. Chemical marker. Flavonoids
Resumo:
Ketoprofeeni on yleisesti käytetty ei-steroidinen tulehduskipulääke (NSAID) lampaiden ja sikojen kivunlievityksessä. Tietoa ketoprofeenin oikeista annosmääristä eri eläinlajeilla on saatavilla rajallisesti. Oikeaa lääkeainemäärää ei voida luotettavasti ekstrapoloida toisten eläinlajien tai ihmisten perusteella. Epäillyissä tulehduskipulääkemyrkytyksissä ongelmana on tietää, oliko eläimen saama lääkeannos toksinen. Lampailla tehdyn tutkimuksen tavoitteena oli selvittää, muuttuuko ketoprofeenin kinetiikka kymmenkertaisella yliannoksella, tutkia yliannoksen vaikutusta munuaisiin ja löytää yksinkertainen tapa diagnosoida yliannos virtsasta. Sioilla tehdyn tutkimuksen tavoitteena oli selvittää ketoprofeenin biologista käytettävyyttä ja ketoprofeenin farmakokinetiikkaa sioilla intravaskulaarisella, intramuskulaarisella ja peroraalisella annolla. Keskeiset tutkimuksessa määritettävät muuttujat olivat AUC0-_, Cmax ja tmax. Hyötyosuus laskettiin i.v. -annon perusteella. Kuudelle lampaalle annettiin 30 mg/kg i.v. -ketoprofeenia. Ketoprofeenin pitoisuuksia seurattiin 24 tunnin ajan plasmanäytteillä, joiden perusteella määritettiin farmakokineettiset parametrit. Veri- ja virtsanäytteistä tutkittiin muun muassa mahdollisesta munuaisvauriosta kertovia entsyymejä. 24 tunnin kuluttua lääkkeenannosta lampaat lopetettiin ja munuaiset tutkittiin histologisesti. Tutkittaville kahdeksalle sialle annosteltiin 3 mg/kg intravaskulaarista, intramuskulaarista ja oraalista ketoprofeenia sekä 6 mg/kg oraalista ketoprofeenia. Tutkimus suoritettiin satunnaistettuna vaihtovuorotutkimuksena. Ketoprofeenin pitoisuuksia seurattiin plasmanäytteillä 48 tunnin ajan lääkkeenannosta ja kaikille antotavoille laskettiin farmakokineettiset parametrit. Lisäksi tutkittiin valmisteiden biologinen samanarvoisuus. Molempien tutkimusten in vivo -kokeet suoritettiin Eläinlääketieteellisessä tiedekunnassa. Samoin munuaisten histologinen tutkimus ja virtsasta ja verestä tehdyt määritykset, lukuun ottamatta ketoprofeeninpitoisuuden analysointia. Plasman ketoprofeenipitoisuus analysoitiin korkean erotuskyvyn nestekromatografialla (HPLC). Ketoprofeenimääritykset ja farmakokineettinen analyysi suoritettiin Farmasian tiedekunnassa. Lampaiden kymmenkertainen ketoprofeeniyliannos oli toksinen. Seerumin urea- ja kreatiniinipitoisuus nousivat ja histologisissa näytteissä näkyi akuutti munuaistiehyen vaurio. Useiden entsyymien pitoisuus nousi virtsassa. Selvimmin ja nopeimmin nousi virtsan laktaattidehydrogenaasipitoisuus, jonka määrittäminen vaikuttaa potentiaaliselta tavalta diagnosoida ketoprofeenin toksinen annos. Ketoprofeenin eliminaation puoliintumisaika toksisella annoksella oli samaa suuruusluokkaa kuin aiemmissa tutkimuksissa terapeuttisella annoksella, joten yliannos ei muuttanut ketoprofeenin kinetiikkaa. AUC- ja Cmax -arvot olivat suhteessa suurempia kuin terapeuttisella annoksella, joten tutkimuksen perusteella kyseiset arvot eivät nousseet lineaarisesti annoksen noustessa toksiseksi. Sioille annetut ketoprofeenivalmisteet eivät olleet biologisesti samanarvoisia keskenään. Hyötyosuus oli erittäin hyvä kaikilla antotavoilla. tmax oli kaikilla antotavoilla hieman yli tunnin kuluttua lääkkeenannosta. Oraalisen 3 mg/kg -annoksen Cmax oli 5,1 mg/l ja AUC 32 mg l-1 h ja intramuskulaarisen vastaavat arvot olivat 7,6 mg/l ja 37 mg l-1 h. Oraalisen ketoprofeenin annostasojen AUC- ja Cmax -arvot korreloivat keskenään, joten ketoprofeenin kinetiikka oli lineaarista. Intravaskulaarisen ja oraalisen annon puoliintumisajoissa oli tilastollisesti merkitsevä ero. Ketoprofeenin jakautumistilavuudessa ja puhdistumassa ei ollut tilastollisesti merkitsevää eroa eri antotapojen välillä.
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Heteronuclear multiple-quantum coherence relaxation rate are calculated for the individual transitions of the S spin in an AIS nuclear spin system assuming that the heteronucleus (S spin) has relaxation contributions from both intramolecular dipole-dipole and chemical shift anisotropy relaxation. The individual multiplet components of the heteronuclear zero- and double-quantum coherences are shown to have different transverse relaxation rates. The cross-correlation between the two relaxation mechanisms is shown to be the dominant cause of the calculated differential line broadening. Experimental data are presented using as an example a uniformly 15N labelled sample of human epidermal growth factor.
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Chemical shifts of K absorption discontinuities, Delta E, of several manganese, iron and cobalt oxides with the metal in the formal oxidation states between +2 and +4, have been measured. These data, together with data in the literature on other compounds of these metals, can be fitted into the expression Delta E=aq+bq2, where q is the effective atomic charge on the metal. Theoretical considerations also support this functional relationship between Delta E and q.
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29Si chemical shifts in a wide variety of silicates in crystalline, glassy and gel states have been related to a parameter, P, which takes into account the electronegativity and the structural description of the silicate units as well as the ionic potential of the modifier cation. The relation, δ(ppm)=28.4 [1−exp(−P)]−110.5, besides having predictive value, satisfactorily accounts for all the available chemical-shifts data on silicates and shows the right kind of limiting behaviour, with δ approaching the Q0 value at large P.
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The high-temperature superconductors are complex oxides, generally containing two-dimensional CuO2 sheets. Various families of the cuprate superconductors are described, paying special attention to aspects related to oxygen stoichiometry, phase stability, synthesis and chemical manipulation of charge carriers. Other aspects discussed are chemical applications of cuprates, possibly as gas sensors and copper-free oxide superconductors. All but the substituted Nd and Pr cuprates are hole-superconductors. Several families of cuprates show a nearly constant n(h) at maximum T(c). Besides this universality, the cuprates exhibit a number of striking common features. Based on Cu(2p) photoemission studies, it is found that the Cu-O charge-transfer energy, DELTA, and the Cu(3d)-O(2p) hybridization strength, t(pd), are key factors in the superconductivity of cuprates. The relative intensity of the satellite in the Cu(2p) core-level spectra, the polarizability of the CuO2 sheets as well as the hole concentration are related to DELTA/t(pd). These chemical bonding factors have to be explicitly taken into account in any model for superconductivity of the cuprates.
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The zeta potential of high-purity hematite at pH 6 and in a 10−3N NaCl solution has been determined at different concentrations of acetone using the streaming potential technique and the results correlated with the microhardness of the mineral. The zeta potential has been found to decrease as the hardness increases reaching a minimum at 10 cc per litre concentration of acetone when the hardness reaches a maximum. The results have been explained on the basis of competitive adsorption of chloride ions and acetone molecules at low concentrations of acetone and coadsorption of both species above 10 cc per litre concentration. Acetone in distilled water and 10−3N NaCl in distilled water decrease the microhardness of hematite individually between pH 5 to 7 and in combination increase the microhardness reaching a maximum at pH 6.
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Glioblastoma (GBM; grade IV astrocytoma) is the most malignant and common primary brain tumor in adults. Using combination of 2-DE and MALDI-TOF MS, we analyzed 14 GBM and 6 normal control sera and identified haptoglobin alpha 2 chain as an up-regulated serum protein in GBM patients. GBM-specific up-regulation was confirmed by ELISA based quantitation of haptoglobin (Hp) in the serum of 99 GBM patients as against lower grades (49 grade III/AA; 26 grade II/DA) and 26 normal individuals (p = 0.0001). Further validation using RT-qPCR on an independent set (n = 78) of tumor and normal brain (n = 4) samples and immunohistochemcial staining on a subset (n = 42) of above samples showed increasing levels of transcript and protein with tumor grade and were highest in GBM (p = < 0.0001 and < 0.0001, respectively). Overexpression of Hp either by stable integration of Hp cDNA or exogenous addition of purified Hp to immortalized astrocytes resulted in increased cell migration. RNAi-mediated silencing of Hp in glioma cells decreased cell migration. Further, we demonstrate that both human glioma and mouse melanoma cells overexpressing Hp showed increased tumor growth. Thus, we have identified haptoglobin as a GBM-specific serum marker with a role on glioma tumor growth and migration.
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A comparison is made between German and Russian terminological derivations in chemistry and the methods used by Germans and Russians to solve problems related to the fornlrrtion of scientific words. A study of this comparison, it is believed, can help us in the development of scientific words in Indian languages.
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In order to evaluate the influence of ambient aerosol particles on cloud formation, climate and human health, detailed information about the concentration and composition of ambient aerosol particles is needed. The dura-tion of aerosol formation, growth and removal processes in the atmosphere range from minutes to hours, which highlights the need for high-time-resolution data in order to understand the underlying processes. This thesis focuses on characterization of ambient levels, size distributions and sources of water-soluble organic carbon (WSOC) in ambient aerosols. The results show that in the location of this study typically 50-60 % of organic carbon in fine particles is water-soluble. The amount of WSOC was observed to increase as aerosols age, likely due to further oxidation of organic compounds. In the boreal region the main sources of WSOC were biomass burning during the winter and secondary aerosol formation during the summer. WSOC was mainly attributed to a fine particle mode between 0.1 - 1 μm, although different size distributions were measured for different sources. The WSOC concentrations and size distributions had a clear seasonal variation. Another main focus of this thesis was to test and further develop the high-time-resolution methods for chemical characterization of ambient aerosol particles. The concentrations of the main chemical components (ions, OC, EC) of ambient aerosol particles were measured online during a year-long intensive measurement campaign conducted on the SMEAR III station in Southern Finland. The results were compared to the results of traditional filter collections in order to study sampling artifacts and limitations related to each method. To achieve better a time resolution for the WSOC and ion measurements, a particle-into-liquid sampler (PILS) was coupled with a total organic carbon analyzer (TOC) and two ion chromatographs (IC). The PILS-TOC-IC provided important data about diurnal variations and short-time plumes, which cannot be resolved from the filter samples. In summary, the measurements made for this thesis provide new information on the concentrations, size distribu-tions and sources of WSOC in ambient aerosol particles in the boreal region. The analytical and collection me-thods needed for the online characterization of aerosol chemical composition were further developed in order to provide more reliable high-time-resolution measurements.
Resumo:
Bile acids are important steroid-derived molecules essential for fat absorption in the small intestine. They are produced in the liver and secreted into the bile. Bile acids are transported by bile flow to the small intestine, where they aid the digestion of lipids. Most bile acids are reabsorbed in the small intestine and return to the liver through the portal vein. The whole recycling process is referred to as the enterohepatic circulation, during which only a small amount of bile acids are removed from the body via faeces. The enterohepatic circulation of bile acids involves the delicate coordination of a number of bile acid transporters expressed in the liver and the small intestine. Organic anion transporting polypeptide 1B1 (OATP1B1), encoded by the solute carrier organic anion transporter family, member 1B1 (SLCO1B1) gene, mediates the sodium independent hepatocellular uptake of bile acids. Two common SNPs in the SLCO1B1 gene are well known to affect the transport activity of OATP1B1. Moreover, bile acid synthesis is an important elimination route for cholesterol. Cholesterol 7α-hydroxylase (CYP7A1) is the rate-limiting enzyme of bile acid production. The aim of this thesis was to investigate the effects of SLCO1B1 polymorphism on the fasting plasma levels of individual endogenous bile acids and a bile acid synthesis marker, and the pharmacokinetics of exogenously administered ursodeoxycholic acid (UDCA). Furthermore, the effects of CYP7A1 genetic polymorphism and gender on the fasting plasma concentrations of individual endogenous bile acids and the bile acid synthesis marker were evaluated. Firstly, a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the determination of bile acids was developed (Study I). A retrospective study examined the effects of SLCO1B1 genetic polymorphism on the fasting plasma concentrations of individual bile acids and a bile acid synthesis marker in 65 healthy subjects (Study II). In another retrospective study with 143 healthy individuals, the effects of CYP7A1 genetic polymorphism and gender as well as SLCO1B1 polymorphism on the fasting plasma levels of individual bile acids and the bile acid synthesis marker were investigated (Study III). The effects of SLCO1B1 polymorphism on the pharmacokinetics of exogenously administered UDCA were evaluated in a prospective genotype panel study including 27 healthy volunteers (Study IV). A robust, sensitive and simple HPLC-MS/MS method was developed for the simultaneous determination of 16 individual bile acids in human plasma. The method validation parameters for all the analytes met the requirements of the FDA (Food and Drug Administration) bioanalytical guidelines. This HPLC-MS/MS method was applied in Studies II-IV. In Study II, the fasting plasma concentrations of several bile acids and the bile acid synthesis marker seemed to be affected by SLCO1B1 genetic polymorphism, but these findings were not replicated in Study III with a larger sample size. Moreover, SLCO1B1 polymorphism had no effect on the pharmacokinetic parameters of exogenously administered UDCA. Furthermore, no consistent association was observed between CYP7A1 genetic polymorphism and the fasting plasma concentrations of individual bile acids or the bile acid synthesis marker. In contrast, gender had a major effect on the fasting plasma concentrations of several bile acids and also total bile acids. In conclusion, gender, but not SLCO1B1 or CYP7A1 polymorphisms, has a major effect on the fasting plasma concentrations of individual bile acids. Moreover, the common genetic polymorphism of CYP7A1 is unlikely to influence the activity of CYP7A1 under normal physiological conditions. OATP1B1 does not play an important role in the in vivo disposition of exogenously administered UDCA.
Resumo:
Chemical shifts, ΔE, of the X-ray K-absorption edge in several compounds, complexes of copper including its superconducting oxides possessing formal oxidation states +1 and +2 have been measured. It has been shown that the chemical shift is primarily governed by the effective ionic charge on the absorbing ion and the nature of the atoms in the first coordination shell around the absorbing ion. The relation between the chemical shift, ΔE , and the effective charge q on the absorbing ion is found to be ΔE=Aq+Bq2+Cq3+Dq4 (A, B, C and D are constants). The effects of electronegativity, atomic number, oxidation state, crystal structure, the valence d-orbital electrons, etc. on the X-ray absorption chemical shift have been discussed. ©1990 The Physical Society of Japan