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2.
Zookeys ; (100): 333-52, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21738420

RESUMO

We investigated the extent of poleward shifts in the distribution range of Agonum viridicupreum due to climate change in the western Palaearctic. Species' records were obtained from extensive literature sources as well as from collections, and consistent amateur entomologists' recordings. Within the general geographic range of the species, we analyzed in detail two parts of both, the northern and southern distribution range boundaries: (1 and 2) north-western Germany (leading or high-latitude edge), (3) Israel and (4) southern Italy (rear or low-latitude edge). Temporal changes in the occurrence data of the species indicated a northward shift of the leading edge of a minimum of 100 km within the last 50 to 100 years. In contrast, according to the data gathered, the rear edge has not changed during the last decades. Further studies are needed in order to fully understand the underlying mechanisms of the different behaviour of leading and rear range edges of Agonum viridicupreum in the current context of global change. Despite our incomplete understanding, chronosequences of the occurrence of the given species have the potential to optimize climate niche modelling to predict trends in the distribution range in the future.

3.
Liver Int ; 30(8): 1181-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20629947

RESUMO

BACKGROUND: Oleic acid is a major systemically circulating fatty acid in humans with atheroprotective and immunomodulatory properties. As of today, the contribution of individual cytochrome P450 (CYP) mono-oxygenases to the epoxidation of this fatty acid is unknown. Furthermore, the extent of the oleic acid oxidation product cis-9,10-epoxyoctadecanoic acid (cis-EODA) in humans and its plasma levels in patients with impaired liver function are not known. PATIENTS AND METHODS: We studied cis-EODA in plasma of patients suffering from chronic liver diseases, a condition that often displays impaired liver CYP enzyme activities. Fifteen CYP mono-oxygenases were investigated in vitro as a potential source of cis-EODA. RESULTS: Strikingly, plasma levels of cis-EODA were significantly repressed (P<0.0005) when patients with liver impairment (n=16) were compared with healthy subjects (n=14). Production of cis-EODA was catalysed by CYP in the following order: 2C8, 2C9, 2C19, 3A4, 1A2 and CYP3A7. CONCLUSION: cis-EODA plasma concentrations are decreased in hepatic disease with impaired liver function. Oleic acid is primarily oxidized to oleic acid oxide (cis-EODA) by CYP2C and CYP3A mono-oxygenases. The liver is the major organ responsible for the oxidation of oleic acid to cis-EODA, and thus, cis-EODA may be a suitable biomarker to assess liver function.


Assuntos
Biomarcadores/sangue , Sistema Enzimático do Citocromo P-450/metabolismo , Hepatopatias/diagnóstico , Hepatopatias/metabolismo , Ácido Oleico/metabolismo , Adulto , Idoso , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Pessoa de Meia-Idade , Estrutura Molecular , Ácido Oleico/sangue , Ácidos Esteáricos/sangue
4.
J Chromatogr B Analyt Technol Biomed Life Sci ; 877(28): 3442-55, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19595646

RESUMO

S-Nitrosothiols from low-molecular-mass and high-molecular-mass thiols, including glutathione, albumin and hemoglobin, are endogenous potent vasodilators and inhibitors of platelet aggregation. By utilizing the S-transnitrosation reaction and by using the lipophilic (pK(L) 0.78) and strong nucleophilic synthetic thiol N-acetyl cysteine ethyl ester (NACET) we have developed a GC-MS method for the analysis of S-nitrosothiols and their (15)N- or (2)H-(15)N-labelled analogs as S-nitroso-N-acetyl cysteine ethyl ester (SNACET) and S(15)NACET or d(3)-S(15)NACET derivatives, respectively, after their extraction with ethyl acetate. Injection of ethyl acetate solutions of S-nitrosothiols produced two main reaction products, compound X and compound Y, within the injector in dependence on its temperature. Quantification was performed by selected-ion monitoring of m/z 46 (i.e., [NO(2)](-)) for SNACET and m/z 47 (i.e., [(15)NO(2)](-)) for S(15)NACET/d(3)-S(15)NACET for compound X, and m/z 157 for SNACET and m/z 160 for d(3)-S(15)NACET for compound Y. In this article we describe the development, validation and in vitro and in vivo applications of the method to aqueous buffered solutions, human and rabbit plasma. Given the ester functionality of SNACET/S(15)NACET/d(3)-S(15)NACET, stability studies were performed using metal chelators and esterase inhibitors. The method was found to be suitable for the quantitative determination of various S-nitrosothiols including SNACET externally added to human plasma (0-10microM). Nitrite contamination in ethyl acetate was found to interfere. Our results suggest that the concentration of endogenous S-nitrosothiols in human plasma does not exceed about 200nM in total. Oral administration of S(15)NACET to rabbits (40-63micromol/kg body weight) resulted in formation of ALB-S(15)NO, [(15)N]nitrite and [(15)N]nitrate in plasma.


Assuntos
Acetatos/química , Cisteína/análogos & derivados , Cromatografia Gasosa-Espectrometria de Massas/métodos , S-Nitrosotióis/química , Adulto , Animais , Cisteína/administração & dosagem , Cisteína/sangue , Cisteína/química , Feminino , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Humanos , Masculino , Nitrosação , Coelhos , S-Nitrosotióis/sangue , Adulto Jovem
5.
Pharm Res ; 25(8): 1822-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18427962

RESUMO

PURPOSE: We investigated the inhibitory effects of curcumin, curcumin derivatives and degradation products on OKT3-induced human peripheral blood mononuclear cell (PBMC) proliferation and the role of their radical scavenging activity. METHODS: OKT3-induced human PBMC proliferation was determined by measuring 3H-thymidine incorporation. Radical scavenging activity was evaluated by using an in vitro DPPH assay. RESULTS: OKT3-induced PBMC proliferation was inhibited by curcumin, isocurcumin, bisdesmethoxy-, diacetyl-, tetrahydro-, hexahydro-, and octahydrocurcumin as well as by vanillin, ferulic acid, and dihydroferulic acid with IC50-values of 2.8, 2.8, 6.4, 1.0, 25, 38, 82, 729, 457, and >1,000 microM, respectively. The investigated substances with the strongest effect on radical scavenging were tetrahydro-, hexahydro-, and octahydrocurcumin with IC50 values of 10.0, 11.7, and 12.3 microM, respectively. IC50-values of dihydroferulic acid, ferulic acid, and curcumin were 19.5, 37, and 40 microM. The substances with the lowest radical scavenging activities were vanillin, isocurcumin, diacetylcurcumin, and bisdesmethoxycurcumin with IC50 values higher than 100 microM each. CONCLUSIONS: Curcuminoid-induced inhibition of OKT3-induced PBMC proliferation depends on the number of carbon atoms and double bonds of the 1,6-heptadiene-3,5-dione structure as well as on the phenolic ring substitutes of the curcuminoids but is not correlated to their respective radical scavenging activity.


Assuntos
Curcumina/análogos & derivados , Curcumina/farmacologia , Sequestradores de Radicais Livres/farmacologia , Linfócitos T/efeitos dos fármacos , Adulto , Compostos de Bifenilo , Complexo CD3/imunologia , Proliferação de Células/efeitos dos fármacos , Curcumina/síntese química , Humanos , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Picratos/farmacologia , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
6.
Aesthet Surg J ; 27(3): 342-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19341663

RESUMO

Water jet-assisted lipoplasty channels a thin, targeted, fan-shaped jet into adipose tissue to loosen tissue structure and release adipocytes. According to the authors, water jet-assisted lipoplasty facilitates preinfiltration of modified tumescent solution to create analgesia, resulting in painless or near painless lipoplasty. The authors contend that, with this method, patient safety has increased considerably, even in extensive procedures.

7.
Anal Chem ; 77(19): 6184-9, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16194077

RESUMO

2D-Fluorescence spectroscopy has been shown to be effective for the on-line monitoring of spectroscopic detectable substrates L-phenylalanine-7-amido-4-methylcoumarine (L-PheAMC) and D-phenylalanine-7-amido-4-trifluoromethylcoumarine (D-PheAFC) in supercritical carbon dioxide. Earlier investigations with the coumarine substrates in watery and organic phases showed their potential for on-line enantiomeric evaluations of enzymatic reactions in different reaction media. The solubility of the different substrates and their fluorescence maximums were investigated in SCCO2. The sole hydrolyzations of L-PheAMC and D-PheAFC with alpha-chymotrypsin and the esterase from porcine liver were tracked on-line in the supercritical medium; however, different solubility characteristics of the methyl- and trifluoromethyl-substituted coumarins influence the simultaneous detection of the L- and D-substrate within the applied high-pressure reactor system.


Assuntos
Dióxido de Carbono/química , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Quimotripsina/metabolismo , Hidrólise , Isomerismo , Sistemas On-Line , Fenilalanina/química , Fenilalanina/metabolismo , Especificidade por Substrato , Temperatura
8.
Artigo em Inglês | MEDLINE | ID: mdl-15081936

RESUMO

Cytochrome P450 dependent epoxidation and non-enzymic lipid peroxidation of oleic acid (cis-9-octadecenoic acid) result in the formation of cis-9,10-epoxyoctadecanoic acid (cis-EODA). This oleic acid oxide has been identified indirectly in blood and urine of humans. Reliable concentrations of circulating cis-EODA have not been reported thus far. In the present article, we report on the first GC-tandem MS method for the accurate quantitative determination in human plasma of authentic cis-EODA as its pentafluorobenzyl (PFB) ester. cis-[9,10-2H2]-EODA (cis-d2-EODA) was synthesized by chemical epoxidation of commercially available cis-[9,10-2H2]-9-octadecenoic acid and used as an internal standard for quantification. Endogenous cis-EODA and externally added cis-[9,10-2H2]-EODA were isolated from acidified plasma samples (1 ml; pH 4.5) by solvent or solid-phase extraction, converted into their PFB esters, isolated by HPLC and quantified by selected reaction monitoring. The parent ions [M-PFB]- at mass-to-charge ratio (m/z) 297 for cis-EODA and m/z 299 for (cis-d2-EODA) were subjected to collisionally-activated dissociation and the corresponding characteristic product ions at m/z 171 and 172 were monitored. In plasma of nine healthy humans (5 females, 4 males), cis-EODA was found to be present at 47.6+/-7.4 nM (mean+/-S.D.). Plasma cis-EODA levels were statistically insignificantly different (P=0.10403, t-test) in females (51.1+/-3.4 nM) and males (43.1+/-2.2 nM). cis-EODA was identified as a considerable contamination in laboratory plastic ware and found to contribute to endogenous cis-EODA by approximately 2 nM. The present GC-tandem MS method should be useful in investigating the physiological role(s) of cis-EODA in humans.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Ácidos Esteáricos/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Valores de Referência
9.
Planta Med ; 69(4): 337-43, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12709901

RESUMO

Former studies have shown that curcumin, which can be extracted from different Curcuma species, is able to stimulate bile flow and to reduce hypercholesterolemia. We investigated in a subchronic bile fistula model the ability of curcumin to reduce cyclosporine-induced cholestasis and hypercholesterolemia. Male Wistar rats were daily treated with curcumin (100 mg/kg p. o.), cyclosporine (10 mg/kg i. p.), and a combination of curcumin with cyclosporine. After two weeks a bile fistula was installed into the rats to measure bile flow and biliary excretion of bile salts, cholesterol, bilirubin, cyclosporine and its main metabolites. Blood was taken to determine the concentration of these parameters in serum or blood. Cyclosporine reduced bile flow (-14 %) and biliary excretion of bile salts (-10 %) and cholesterol (-61 %). On the other hand, cyclosporine increased serum concentrations of cholesterol and triglycerides by 32 % and 82 %, respectively. Sole administration of curcumin led to a slight decrease of bile flow (-7 %) and biliary bile salt excretion (-12 %), but showed no effect on biliary excretion of cholesterol and serum lipid concentration. When curcumin was given simultaneously with cyclosporine, the cyclosporine-induced cholestasis was enhanced but the cyclosporine-induced hyperlipidemia was not affected. Neither the biliary excretion nor the blood concentration of cyclosporine was influenced by curcumin. The blood concentration of the main cyclosporine metabolites, however, was lowered by half while their biliary excretion was strongly increased by curcumin. From these results we conclude that curcumin is not able to prevent cyclosporine-induced cholestasis and hyperlipidemia after prolonged administration in bile fistula rats.


Assuntos
Colagogos e Coleréticos/farmacologia , Curcuma , Curcumina/farmacologia , Ciclosporina/farmacocinética , Hipolipemiantes/farmacologia , Imunossupressores/farmacocinética , Fitoterapia , Administração Oral , Animais , Bile/metabolismo , Ácidos e Sais Biliares/sangue , Fístula Biliar , Colagogos e Coleréticos/administração & dosagem , Colagogos e Coleréticos/uso terapêutico , Colestase/induzido quimicamente , Colestase/tratamento farmacológico , Colesterol/sangue , Curcumina/administração & dosagem , Curcumina/uso terapêutico , Ciclosporina/metabolismo , Modelos Animais de Doenças , Hipercolesterolemia/induzido quimicamente , Hipercolesterolemia/tratamento farmacológico , Hipolipemiantes/administração & dosagem , Hipolipemiantes/uso terapêutico , Imunossupressores/metabolismo , Injeções Intraperitoneais , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Triglicerídeos/sangue
10.
Artigo em Inglês | MEDLINE | ID: mdl-12505783

RESUMO

Oleic acid, cis-9-octadecenoic acid, is the major fatty acid in mammals. Its oxide, cis-9,10-epoxyoctadecanoic acid (cis-EODA), has been identified in blood and urine of humans, its origin is, however, still unknown. Lipid peroxidation and enzyme-catalyzed epoxidation of oleic acid are two possible sources. In the present article, we investigated by HPLC and GC-MS whether cis-EODA is formed enzymatically from oleic acid by the cytochrome P450 (CYP) system. Oleic acid, cis-EODA and its hydratation product threo-9,10-dihydroxyoctadecanoic acid (threo-DiHODA) were quantitated by HPLC as their p-bromophenacyl esters. For structure elucidation by GC-MS, the pentafluorobenzyl (PFB) esters of these compounds were isolated by HPLC and converted to their trimethylsilyl ether derivatives. Liver microsomes of rats, rabbits and humans oxidized oleic acid into cis-EODA. This is the first direct evidence for the enzymatic formation of cis-EODA from oleic acid. The epoxidation of oleic acid was found to depend on CYP, NADPH+H(+), and O(2). cis-EODA was measurable in incubates of liver microsomes for up to 30 min of incubation. Maximum cis-EODA concentrations were reached after 5-7 min of incubation and found to depend upon oleic acid concentration. Isolated rat hepatocytes hydratated cis-EODA into threo-DiHODA which was further converted to unknown metabolites. However, from incubation of oleic acid with these cells we could not detect threo-DiHODA or cis-EODA. Our study suggests that circulating and excretory cis-EODA may originate, at least in part, from CYP-catalyzed epoxidation of oleic acid. GC-MS of intact cis-EODA as its PFB ester in the negative-ion chemical ionization mode should be useful in investigating the physiological role of cis-EODA in man.


Assuntos
Ácidos Graxos/biossíntese , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hepatócitos/metabolismo , Microssomos Hepáticos/metabolismo , Ácido Oleico/metabolismo , Animais , Cromatografia Líquida de Alta Pressão/métodos , Inibidores das Enzimas do Citocromo P-450 , Compostos de Epóxi/metabolismo , Ácidos Graxos/metabolismo , Cinética , Oxirredução , Ratos
11.
Oecologia ; 115(1-2): 1-8, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28308439

RESUMO

The ability of gametophytes of two Bryidae, Atrichum undulatum (Hedw.) P. Beauv. and Polytrichum formosum Hedw., to rapidly acquire thermotolerance was investigated by measuring chlorophyll a fluorescence and electrolyte leakage. Short-term acclimation of turgid shoots to elevated sublethal temperatures resulted in a small but significant increase in the heat stability of the photosynthetic apparatus and of cellular membranes by around 1 K, indicating that the heat hardening capacity of hydrated mosses is very low. While thermal adaptation occurred within few hours, dehardening required several days. The pattern of rapid thermal hardening and dehardening of turgid mosses resembles that of flowering plants. However, as opposed to the low potential for short-term thermal acclimation of hydrated gametophytes, a dramatic rise in heat resistance occurred with decline of the water content of the poikilohydric shoots, which was achieved either by equilibrating of the thalli at different relative humidities or by incubation in sugar solutions of various concentrations. The lower the water potential of the tissue the higher the heat tolerance of the shoots. The data show that in contrast to homoiohydric higher plants, in desiccation-resistant mosses changes in the water status of the thalli play the dominant role in short-term variations of thermal tolerance rather than specific heat hardening and dehardening reactions.

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