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1.
Clin Biochem ; 42(6): 448-54, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19297679

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the possible urinary markers of hormonal activity in patients with non-functioning adrenal incidentalomas. In order to evaluate the endocrine activity of aforementioned tumours, urinary steroid metabolite levels were analyzed in samples from patients and controls. Possible blocks in metabolic pathways of the examined hormones were determined by comparing selected urinary steroid metabolite sums and ratios in both groups of interest. DESIGN: Urine samples were collected from 20 patients with non-functioning adrenal incidentalomas and from 25 controls matched in terms of age, sex and BMI. Excretion of 19 major urinary steroid metabolites was analyzed by gas chromatography. The results were subjected to statistical analysis. RESULTS: In patients with adrenal incidentalomas sum of total urinary cortisol metabolites was significantly increased in respect to the control group. We also observed a shift towards tetrahydrocorticosterone, cortisol and etiocholanolone production in patients. No significant differences in production of other urinary steroid metabolites were noted in patients with adrenal incidentalomas in respect to control group. CONCLUSIONS: Our data suggests that not only urinary free cortisol but also its metabolite such as tetrahydrocortisol and other steroids including etiocholanolone and corticosterone tetrahydrometabolite might be urinary markers for the endocrine activity of adrenal incidentalomas. Enhanced levels of these urinary steroid metabolites indicate an impairment of 11beta-hydroxysteroid dehydrogenase activity and slightly increased activity of 5beta-reductase in patients with adrenal incidentalomas.


Subject(s)
Adrenal Gland Neoplasms/urine , Pheochromocytoma/urine , Steroids/urine , 11-beta-Hydroxysteroid Dehydrogenases/metabolism , Adrenal Gland Neoplasms/enzymology , Adult , Aged , Biomarkers, Tumor/urine , Chromatography, Gas , Corticosterone/analogs & derivatives , Corticosterone/urine , Etiocholanolone/urine , Female , Humans , Hydrocortisone/urine , Male , Middle Aged , Oxidoreductases/metabolism , Pheochromocytoma/enzymology , Tetrahydrocortisol/urine
2.
Insect Biochem Mol Biol ; 38(6): 619-27, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18510973

ABSTRACT

Epicuticular lipids in many terrestrial arthropods consist of vast numbers of polar and non-polar aliphatic compounds, which are mainly responsible for the water balance in these animals but can also affect conidia germination of entomopathogenic fungi. In this work the qualitative and quantitative profiles of cuticular fatty acids from three insect species differing in their susceptibility to fungal infection were studied. In an innovative approach, laser light scattering detection was coupled with HPLC in order to identify the non-chromophoric chemicals usually present in cuticular extracts. The acids identified contained from 5 to 20 carbon atoms in the alkyl chain and included unsaturated entities such as C(16:1), C(18:1), C(18:2), C(18:3) and C(20:1). There was a marked dominance of acids containing 16-18 carbon atoms. The relative contents of fatty acids in the extracted waxes varied from trace amounts to 44%. Cuticular fatty acids profile of Calliphora vicina (species resistant to fungal infection) significantly differs from profiles of Dendrolimus pini and Galleria mellonella (both species highly susceptible to fungal infection). The major difference is the presence of C(14:0), C(16:1) and C(20:0) in the cuticle of C. vicina. These three fatty acids are absent in the cuticle of D. pini while G. mellonella cuticle contains their traces. The concentrations of four fatty acids dominating in the G. mellonella larval cuticle (C(16:0), C(18:0), C(18:1) and C(18:2)) were found to fluctuate during the final larval instar and correlate with fluctuations in the susceptibility of larvae to fungal infection. The possible role of cuticular fatty acids in preventing fungal infection is discussed.


Subject(s)
Conidiobolus/immunology , Diptera/immunology , Fatty Acids/metabolism , Host-Pathogen Interactions , Moths/immunology , Animals , Diptera/metabolism , Diptera/microbiology , Larva/immunology , Larva/metabolism , Larva/microbiology , Moths/metabolism , Moths/microbiology
3.
Biotechnol Appl Biochem ; 51(Pt 2): 91-6, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18211259

ABSTRACT

Common rue (Ruta graveolens L.) accumulates various types of secondary metabolites, such as coumarins furanocoumarins, acridone and quinolone alkaloids and flavonoids. Elicitation is a tool extensively used for enhancing secondary-metabolite yields. Chitin and chitosan are examples of elicitors inducing phytoalexin accumulation in plant tissue. The present paper describes the application of chitin and chitosan as potential elicitors of secondary-metabolite accumulation in R. graveolens shoots cultivated in vitro. The simple coumarins, linear furanocoumarins, dihydrofuranocoumarins and fluoroquinolone alkaloids biosynthesized in the presence of chitin and chitosan were isolated, separated and identified. There was a significant increase in the growth rate of R. graveolens shoots in the presence of either chitin or chitosan. Moreover, the results of the elicitation of coumarins and alkaloids accumulated by R. graveolens shoots in the presence of chitin and chitosan show that both compounds induced a significant increase in the concentrations of nearly all the metabolites. Adding 0.01% chitin caused the increase in the quantity (microg/g dry weight) of coumarins (pinnarin up to 116.7, rutacultin up to 287.0, bergapten up to 904.3, isopimpinelin up to 490.0, psoralen up to 522.2, xanhotoxin up to 1531.5 and rutamarin up to 133.7). The higher concentration of chitosan (0.1%) induced production of simple coumarins (pinnarin up to 116.7 and rutacultin up to 287.0), furanocoumarins (bergapten up to 904.3, isopimpinelin up to 490.0, psoralen up to 522.2, xanhotoxin up to 1531.5) and dihydrofuranocoumarins (chalepin up to 18 and rutamarin up to 133.7). Such a dramatic increase in the production of nearly all metabolites suggests that these compounds may be participating in the natural resistance mechanisms of R. graveolens. The application of chitin- and chitosan-containing media may be considered a promising prospect in the biotechnological production of xanthotoxin, isopimpinelin, psoralen, chalepin or methoxylated dictamnine derivatives.


Subject(s)
Alkaloids/biosynthesis , Chitin/pharmacology , Chitosan/pharmacology , Coumarins/metabolism , Fluoroquinolones/metabolism , Ruta/metabolism , Alkaloids/isolation & purification , Coumarins/isolation & purification , Dose-Response Relationship, Drug , Fluoroquinolones/isolation & purification , Plant Roots/drug effects , Plant Roots/metabolism , Ruta/drug effects
4.
Biotechnol Prog ; 24(1): 128-33, 2008.
Article in English | MEDLINE | ID: mdl-18052337

ABSTRACT

The study aimed to elucidate the effects of benzothiadiazole (BTH) and saccharin on the biosynthesis of simple coumarins, linear furanocoumarins, dihydrofuranocoumarins, and furoquinolone alkaloids in shoots of R. graveolens cultivated in vitro. The biosynthesized metabolites were analyzed and identified by GC-MS and by comparison of Kovats indices. Eight coumarin metabolites were identified: bergapten, chalepin, isopimpinelin, pinnarin, psoralen, rutacultin, rutamarin, and xanthotoxin, and also four alkaloids: dictamnine, gamma-fagarine, skimmianine, and kokusaginine. Each of the tested BTH concentrations induced a significant production of furanocoumarins and furoquinolone alkaloids. The use of saccharin also increased the production of bergapten, isopimpinelin, pinnarin, psoralen, and xanthotoxin several times.


Subject(s)
Ruta/drug effects , Ruta/metabolism , Saccharin/pharmacology , Thiadiazoles/pharmacology , 5-Methoxypsoralen , Benzopyrans/chemistry , Benzopyrans/metabolism , Coumarins/chemistry , Coumarins/metabolism , Ficusin/chemistry , Ficusin/metabolism , Furocoumarins/chemistry , Furocoumarins/metabolism , Gas Chromatography-Mass Spectrometry , Gene Expression Regulation, Plant/drug effects , Methoxsalen/analogs & derivatives , Methoxsalen/chemistry , Methoxsalen/metabolism , Plant Shoots/drug effects , Plant Shoots/metabolism , Quinolines/chemistry , Quinolines/metabolism
5.
Comp Biochem Physiol B Biochem Mol Biol ; 147(2): 288-92, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17337349

ABSTRACT

The Western Flower Thrips Frankliniella occidentalis effectively resists many insecticides, but it can be controlled by the use of bioinsecticides such as entomopathogenic fungi. The epicuticular chemistry of these insects is therefore of great interest, and accordingly, the cuticular lipid composition of F. occidentalis was analysed. It was found that the cuticular lipids of both the adult and larval stages of F. occidentalis consist of two groups of compounds--hydrocarbons and free fatty acids. The same hydrocarbon pattern was found in both adults and larvae, with the exception of n-hentriacontane, which was detected only in adult insects. The following homologous series were identified: n-alkanes from C-25 to C-29 (31) with the marked dominance of odd numbers of carbon atoms, 3-methylalkanes with 26 and 28 carbon atoms, and branched monomethylalkanes (branched at C-9, -11, -13 and -15) with 26, 28 and 30 carbon atoms. The chemical composition of the free fatty acids consists of two homologous series: saturated (C(14:0), C(16:0), C(18:0)) and unsaturated fatty acids (C(16:1) and C(18:1)). This analysis confirmed the lack of potential inhibitors of entomopathogenic fungi in the cuticular lipids of this insect species.


Subject(s)
Fatty Acids/analysis , Hydrocarbons/analysis , Insecta/chemistry , Integumentary System , Animals , Gas Chromatography-Mass Spectrometry , Larva/chemistry
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