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1.
J Biol Regul Homeost Agents ; 30(2): 433-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27358129

RESUMO

Some reports confirm a potential role of Chlamydia pneumoniae (ChP) in atherogenesis. In order to explore possible association between ChP and atherosclerosis, investigations were carried out in which the frequency of ChP in the arterial wall and peripheral blood was assessed in a group of patients with chronic coronary artery disease (CAD). Fifty-seven patients were enrolled in the study, 13 women and 44 men aged 61.8±6.5 (47-74), with previously diagnosed CAD, scheduled for planned coronary artery bypass grafting due to clinical indications. Vessel specimens retrieved from the ascending aorta (as a part of routine proximal venous graft development procedure) and peripheral blood mononuclear cells (PBMCs) from venous blood were evaluated for the presence of ChP DNA. Genomic DNA was extracted from PBMCs and vessel specimens. Quantitative real-time polymerase chain reaction (qPCR) was performed to detect ChP DNA. A statistically more frequent occurrence of ChP was observed in aortic tissues compared to blood samples (70.2% vs 56.1%, respectively). Similarly, the number of ChP DNA genomic copies [n/1µg genomic DNA] was significantly higher in tissue specimens compared to blood samples (89±91 vs 41±77, respectively; p=0.0046). In patients without ChP in blood specimens, we observed significantly higher amounts of ChP in tissue specimens compared to patients with ChP in blood specimens (156±71 vs 107±88, respectively; p=0.0453). No correlation was found between the number of ChP DNA copies [n/1µg genomic DNA] in blood and in aortic specimens. The infection of ChP in the aortic wall was connected with hypercholesterolemia (p=0.029) and diabetes (p=0.03). We conclude that Chlamydia pneumoniae is a pathogen frequently occurring in the aortic wall of patients with CAD. The occurrence of ChP DNA in the aortic tissue is related to classic CAD risk factors such as diabetes and dyslipidemia.


Assuntos
Aorta/microbiologia , Chlamydophila pneumoniae/isolamento & purificação , Ponte de Artéria Coronária , Idoso , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/etiologia , Doença da Artéria Coronariana/microbiologia , DNA Bacteriano/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
2.
Biol Sport ; 31(2): 85-93, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24899771

RESUMO

The final tournament of the UEFA European Football Championship is one of the top sporting events in the world, and a high-profile event of this kind requires a well-planned and well-executed anti-doping programme to ensure the integrity of results in the competition. UEFA EURO 2012 presented a unique logistical challenge, with the tournament spread across two countries, both covering a large geographical area. This paper discusses the planning and delivery of both the pre tournament out-of-competition (OOC) testing programme and the in-competition (IC) programme, as well as reviewing the activities of doping control officers (DCOs), the whereabouts programme and assessing the sample collection and transport process. The analytical approach applied is also discussed, along with an overview of the distribution of T/E ratios and blood parameters.

3.
Int J Sports Med ; 30(8): 569-72, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19382058

RESUMO

Pseudoephedrine (PSE) as a sympathomimetic is an ingredient of many proprietary medicines which are available on the medical market over the counter (OTC drugs). It can be converted to cathine (CATH, norpseudoephedrine) inside the body. Until the end of 2003, PSE had been a banned substance in sport in case its urinary concentration was greater than 25 mircog/ml. Then the World Anti-Doping Agency (WADA) removed PSE from the prohibited list. Prior to 2004 CATH was a forbidden substance and it is still one. CATH is included on the WADA prohibited list in the group of stimulants. The results of a doping control concerning PSE conducted in the Department of Anti-Doping Research of Institute of Sport in Warsaw in the years 2001-2003 and 2004-2007 have been compared. Moreover, several dozen of urine samples collected from the patients taking OTC drugs with PSE have been analysed. In these samples the concentration of PSE and CATH has been estimated. The results of this study have shown that athletes were using PSE frequently and in high doses between 2004 and 2007 when this substance was permitted by WADA. It is possible that athletes can obtain a positive result of doping control with CATH after the use of PSE.


Assuntos
Depressores do Apetite , Desempenho Atlético , Broncodilatadores/urina , Dopagem Esportivo , Drogas Ilícitas , Fenilpropanolamina/urina , Pseudoefedrina/urina , Esportes , Humanos , Medicina Esportiva
4.
PPAR Res ; 2016: 7508026, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26981112

RESUMO

This study aimed to define relationship between PPARα expression and metabolic-structural characteristics during HF progression in hearts with DCM phenotype. Tissue endomyocardial biopsy samples divided into three groups according to LVEF ((I) 45-50%, n = 10; (II) 30-40%, n = 15; (III) <30%, n = 15; and control (donor hearts, >60%, n = 6)) were investigated. The PPARα mRNA expression in the failing hearts was low in Group (I), high in Group (II), and comparable to that of the control in Group (III). There were analogous changes in the expression of FAT/CD36 and CPT-1 mRNA in contrast to continuous overexpression of GLUT-4 mRNA and significant increase of PDK-4 mRNA in Group (II). In addition, significant structural changes of cardiomyocytes with glycogen accumulation were accompanied by increased expression of PPARα. For the entire study population with HF levels of FAT/CD36 mRNA showed a strong tendency of negative correlation with LVEF. In conclusion, PPARα elevated levels may be a direct cause of adverse remodeling, both metabolic and structural. Thus, there is limited time window for therapy modulating cardiac metabolism and protecting cardiomyocyte structure in failing heart.

5.
Biochim Biophys Acta ; 956(3): 232-42, 1988 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-2844270

RESUMO

Rabbit liver phosphofructo-1-kinase, designated isozyme B, and rabbit brain phosphofructokinase, which contains all three isozymes as heteropolymers, have been modified by [14C]fluorosulfonylbenzoyladenosine (FSBAdo). Several lines of evidence supported modification at the binding site for AMP. The modification proceeded to the extent of 2 to 4 mol of reagent incorporated per mol of tetramer, and AMP protected against the reaction. The kinetic properties of modified isozymes A and B and of modified brain phosphofructokinase were examined and compared to their unmodified forms. It was observed that modification greatly diminished ATP inhibition of all of the isozymes. Furthermore, equilibrium binding studies of modified phosphofructokinase B showed a greatly diminished capacity and affinity for cyclic AMP. Cyclic AMP had little or no influence on the properties of modified A isozyme or brain phosphofructokinase, but was capable of further deinhibiting modified B isozyme, apparently at sites remaining unmodified by FSBAdo. Phosphofructokinase B, modified by radiolabeled FSBAdo, was digested by trypsin, and the digest separated by high-pressure liquid chromatography. The labeled peptide was isolated and sequenced to provide the sequence: Asn-Tyr-Gly-Thr-Lys-Leu-Gly-Val-Lys, with the lysine in the fifth position being the site of modification. To isolate isozyme C, a monoclonal antibody to this isozyme was produced by injecting purified rabbit brain phosphofructokinase into mice, and subsequently selecting for those clones that recognized brain phosphofructokinase but not purified phosphofructokinases A and B. The selected monoclonal was specific for native rabbit isozyme C and would not recognize mouse or rat brain phosphofructokinases. Linking the antibody to an inert phase provided an efficient means of purifying rabbit isozyme C from rabbit brain. The enzyme so recovered retained little of its original activity, but the method provided a simple technique for the preparation of enzyme for protein chemistry studies. The modified C isozyme was isolated on the immuno-affinity column and digested with trypsin. A tryptic peptide bearing the label was isolated and sequenced to provide the structure: Asn-Phe-Gly-Thr-Lys-Ile-Ser-Ala-Arg, with position 5 being the site of modification. The sequences of isozymes B and C are homologous to the site of modification of the A isozyme by FSBAdo.


Assuntos
Monofosfato de Adenosina/metabolismo , Isoenzimas/metabolismo , Fosfofrutoquinase-1/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Marcadores de Afinidade/metabolismo , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/isolamento & purificação , Sítios de Ligação , AMP Cíclico/farmacologia , Isoenzimas/imunologia , Isoenzimas/isolamento & purificação , Cinética , Fígado/enzimologia , Fragmentos de Peptídeos/análise , Fosfofrutoquinase-1/imunologia , Fosfofrutoquinase-1/isolamento & purificação , Coelhos , Tripsina
6.
Biochim Biophys Acta ; 995(2): 187-94, 1989 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-2539199

RESUMO

The three isozymic subunits of phosphofructo-1-kinase present in rabbit brain and designated A, B and C were phosphorylated in vitro by cyclic AMP-dependent protein kinase with 32P-labeled ATP. Limited digestion of the labeled enzymes with trypsin or with Staphylococcus aureus V8 proteinase led to the solubilization of radiolabeled peptides derived from the three isozymic subunits. Limited digestion by V8 proteinase was accompanied by a slight reduction in the apparent sizes of the subunits, indicating that the phosphorylated sites are located near either the amino or carboxyl termini of the protein. V8 proteinase digestion led to no change in the maximal activity of the enzyme but did abolish sensitivity to ATP inhibition. The phosphopeptides of the tryptic and the V8 digests were purified by chromatography and their amino acid sequences were determined and compared to the previously established sequence from rabbit muscle isozyme A. PFK-A E H I S R K R S G E A T V PFK-B H V T R R S L S M A K G F PFK-C V S A S P R G S Y R K F L In each instance, the phosphorylated serine, underlined in the above sequences, was found to be one or two residues toward the C-terminus of one or more basic residues. No other similarities in structure were noted.


Assuntos
Encéfalo/enzimologia , AMP Cíclico/farmacologia , Isoenzimas/metabolismo , Fosfofrutoquinase-1/metabolismo , Proteínas Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Dados de Sequência Molecular , Fragmentos de Peptídeos/metabolismo , Fosforilação , Coelhos , Homologia de Sequência do Ácido Nucleico , Serina Endopeptidases/metabolismo , Tripsina/metabolismo
7.
Clin Chim Acta ; 83(1-2): 75-9, 1978 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23232

RESUMO

Erythrocyte glucose-6-phosphate dehydrogenase from patients with acute viral hepatitis has been purified and characterized. The enzyme showed decreased activity (relative to protein), reduced affinity for glucose 6-phosphate and was inactivated at 45 degrees C or at low pH values. The activity and properties of normal erythrocyte enzyme, incubated in vitro with blood plasma of patients, showed a similar pattern of modifications. Incubation with bilirubin affected the enzyme stability, but not its activity or affinity for substrate.


Assuntos
Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/sangue , Hepatite Viral Humana/enzimologia , Bilirrubina , Glucose-6-Fosfatase/metabolismo , Hepatite Viral Humana/sangue , Temperatura Alta , Humanos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , NADP/metabolismo
8.
Arch Immunol Ther Exp (Warsz) ; 34(4): 445-50, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2948478

RESUMO

Phosphofructokinase isolated from human erythrocytes incubated with cortisol showed alterations in regulatory properties. The enzyme was more sensitive to the inhibition by ATP and citrate. This effect was abolished by alanine. Similar changes in phosphofructokinase properties were found after incubation with aldosterone and corticosterone.


Assuntos
Corticosteroides/farmacologia , Eritrócitos/enzimologia , Fosfofrutoquinase-1/sangue , Trifosfato de Adenosina/farmacologia , Aldosterona/farmacologia , Citratos/farmacologia , Ácido Cítrico , Corticosterona/farmacologia , Eritrócitos/efeitos dos fármacos , Humanos , Hidrocortisona/farmacologia , Técnicas In Vitro , Cinética , Fosfofrutoquinase-1/antagonistas & inibidores
9.
Arch Immunol Ther Exp (Warsz) ; 31(3): 381-7, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6228205

RESUMO

After incubation of rabbit red blood cells with 10 micrograms/ml of cortisol, a decrease of the activity of glucose-6-phosphate dehydrogenase, phosphofructokinase and acid phosphatase was observed. Glucose-6-phosphate dehydrogenase and phosphofructokinase were isolated from hemolysate and investigated. No changes in the affinity of both enzymes towards substrates and coenzymes were found. Cortisol modified allosteric properties of phosphofructokinase. Differences were seen between the erythrocyte and reticulocyte enzyme. In the erythrocyte enzyme the inhibitory effect of ATP and citrate was enhanced and the activatory effect of AMP was abolished after incubation with cortisol. Cortisol showed no effect on the inhibition of reticulocyte phosphofructokinase by ATP or activation by AMP, and protected the enzyme toward inhibition by citrate.


Assuntos
Eritrócitos/efeitos dos fármacos , Hidrocortisona/farmacologia , Fosfofrutoquinase-1/sangue , Reticulócitos/efeitos dos fármacos , Fosfatase Ácida/sangue , Monofosfato de Adenosina/farmacologia , Trifosfato de Adenosina/farmacologia , Animais , Citratos/farmacologia , Ácido Cítrico , Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/sangue , Técnicas In Vitro , Coelhos , Reticulócitos/enzimologia
10.
Arch Immunol Ther Exp (Warsz) ; 28(5): 815-23, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6452104

RESUMO

Bilipolinum (Adipiodon), iodine contrast medium used in cholangiography, showed an inhibitory effect on the activity of human erythrocyte phosphohexoseisomerase, phosphofructokinase, aldolase and glucose-6-phosphate dehydrogenase. The addition of glucose metabolites (glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-bis-phosphate, pyruvate and lactate) abolished the inhibitory effect of Bilipolinum. In the presence of Bilipolinum purified erythrocyte phosphofructokinase showed a decreased affinity towards substrate, modified allosteric properties and reduced stability at pH below 7.5. Purified erythrocyte glucose-6-phosphate dehydrogenase was also affected by Bilipolinum and its affinity for NADP was decreased. Testing of erythrocyte enzymes in the evaluation of toxicity of iodine contrast media is discussed.


Assuntos
Meios de Contraste/farmacologia , Eritrócitos/enzimologia , Iodopamida/farmacologia , Frutose-Bifosfato Aldolase/sangue , Glucose-6-Fosfato Isomerase/sangue , Glucosefosfato Desidrogenase/sangue , Humanos , Fosfofrutoquinase-1/sangue
11.
Arch Immunol Ther Exp (Warsz) ; 49(5): 391-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11798137

RESUMO

The aim of this study was to evaluate the effect of lipopolysaccharide (LPS) administration, which mimics a surgical intervention, on the immune status of obstructive jaundiced (OJ) and sham-operated control rats. Rats were given 20 microgram LPS intraperitoneally on day 13 following bile duct ligation or sham surgery. We determined serum levels of tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) on day 14 after surgery, and spontaneous as well as LPS-induced production of these cytokines in splenocyte and peritoneal exudate cell (PEC) cultures. We found that IL-6, but not TNF-alpha, serum concentrations were significantly elevated (4-fold) in OJ rats treated with LPS compared with LPS-untreated OJ rats. In sham-operated rats the differences between the respective groups were not significant. The production of TNF-alpha by splenocyte and PEC cultures was depressed in OJ rats treated with LPS; in particular, a very deep decline was observed in the case of spontaneous TNF-alpha production in PEC cultures. In contrast, TNF-alpha production in LPS-untreated and LPS-treated sham-operated rats did not differ. In the case of IL-6 production by splenocytes and PEC cultures, we observed a significant suppression of this cellular function in both OJ and sham-operated rats treated with LPS when compared with the respective controls. In conclusion, the results indicate that the already depressed cytokine production in OJ rats leads to even deeper hyporeactivity following LPS challenge. Lack of TNF-alpha suppression upon LPS treatment in sham-operated rats suggests that surgery-elicited hyporeactivity is mediated by a different mechanism than that leading to immune hyporesponsiveness in OJ. Our findings may explain the relatively high mortality rates observed of OJ patients subjected to surgery.


Assuntos
Colestase/imunologia , Citocinas/biossíntese , Lipopolissacarídeos/toxicidade , Animais , Líquido Ascítico/imunologia , Colestase/cirurgia , Citocinas/sangue , Técnicas In Vitro , Interleucina-6/biossíntese , Interleucina-6/sangue , Masculino , Ratos , Ratos Endogâmicos BUF , Baço/imunologia , Fator de Necrose Tumoral alfa/biossíntese
12.
Neoplasma ; 27(4): 415-22, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6450330

RESUMO

An increase in lactate production, and in activities of phosphohexoisomerase, phosphofructokinase and pyruvate kinase was found in erythrocytes of patients with advanced cancer disease. Phosphofructokinase isolated from patients' erythrocytes showed enhanced affinity for substrate and coenzyme, diminished thermal stability and changed dependence of the activity on pH. Allosteric properties of the enzyme were modified. A decrease in glucose-6-phosphate dehydrogenase activity was observed in hemolysate. The partially purified enzyme showed decreased affinity for glucose-6-phosphate, and markedly reduced stability at 45 degrees C and in the acid and alkaline pH range. Changes in kinetic and molecular properties of the two key enzymes of glucose metabolism may contribute to hemolysis observed in many cancer patients. Incubation in vitro of normal human erythrocytes with blood sera of patients resulted in increasing of phosphofructokinase, and decreasing of glucose-6-phosphate dehydrogenase activity, indicating that an acquired enzymopathy may be present in cancer.


Assuntos
Eritrócitos/enzimologia , Glucosefosfato Desidrogenase/metabolismo , Neoplasias/enzimologia , Fosfofrutoquinase-1/metabolismo , Humanos , Lactatos/biossíntese
13.
Gen Physiol Biophys ; 17(1): 25-36, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9675554

RESUMO

The interaction of platinum complexes with bovine heart pyruvate kinase (PK) was studied by absorption, CD, fluorescence spectroscopy and enzymic activity test. Our results showed that activity of PK was reduced by cis-DDP and potassium tetrachloroplatinate in a time-and concentration dependent manner. Cis-DDP was less effective than K2PtCl4 in reducing PK activity. The native enzyme showed well defined negative Cotton effect at 222 and 208 nm indicating the presence of alpha-helical and beta structure. Platinum binding lowered the Cotton effect in this region by about 10-20% and 30-50% for the system with cis-DDP and K2PtCl4, respectively. Fluorescence study showed that platinum binding quenched tryptophan fluorescence suggesting that binding occurs at the tryptophan residue or its proximity. PK modifications induced by platinum binding would result in a greater resistance to denaturing agents.


Assuntos
Cloretos/farmacologia , Cisplatino/farmacologia , Miocárdio/enzimologia , Compostos de Platina/farmacologia , Piruvato Quinase/química , Piruvato Quinase/metabolismo , Animais , Bovinos , Dicroísmo Circular , Cinética , Estrutura Secundária de Proteína/efeitos dos fármacos , Espectrometria de Fluorescência , Espectrofotometria
14.
Kardiol Pol ; 37(9): 146-50, 1992 Sep.
Artigo em Polonês | MEDLINE | ID: mdl-1479771

RESUMO

4 patients (P) with recurrent, sustained ventricular tachycardia (VT) resistant to medical treatment, underwent surgery for cure of this arrhythmia. Each P had episodes of VT lasting 30 or more seconds, 3 of them had episodes of ventricular fibrillation. In all cases rhythm disturbances were secondary to post myocardial infarction aneurysm. Coronary angiography showed in all P total occlusion of LAD, in 2 cases significant lesion in RCA were found. 1 P had lung cancer. All P underwent aneurysmectomy and an excision of the altered endocardium by Harken's method. The endocardial excision was performed without endocardial mapping. 2 P had concomitant CABG to RCA. In the P with lung cancer lobectomy was performed. There were 2 ++non-arrhythmic death. The P with lung cancer died because of sepsis due to lung abscess. One P died because of heart failure (preoperative EF 10%), 6 months after the surgery. The 2 survivors remained free of VT during a follow-up period 8 months. In conclusion, endocardial excision by Harken's method is efficient in treating recurrent sustained VT, resistant to medical treatment, in patients with post myocardial infarction aneurysm. The surgical procedure can be performed without intraoperative endocardial mapping.


Assuntos
Endocárdio/cirurgia , Aneurisma Cardíaco/complicações , Infarto do Miocárdio/complicações , Taquicardia Ventricular/cirurgia , Seguimentos , Aneurisma Cardíaco/cirurgia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/fisiopatologia
15.
Przegl Epidemiol ; 45(3): 191-6, 1991.
Artigo em Polonês | MEDLINE | ID: mdl-1819815

RESUMO

The authors analysed 2,575 case histories of children hospitalised in 1981-1985 at pediatric department of regional hospital in Trzcianka (Pila region) taking to account: age, sex, permanent residence, duration of stay at a hospital, disease causing hospitalisation. Within the period studied both decrease of number of neonates (1-6 months old) and young children of (1-3 years old) admitted to the hospital and a tendency toward shortening time of hospitalisation were found. Among causes of hospitalisation the first were respiratory tract infections (88.3% of all admissions in 1981 but 69.8% in 1985), and acute diarrheas (22.1% of all admissions in 1981, 17.1% in 1985).


Assuntos
Hospitalização/estatística & dados numéricos , Hospitais Comunitários/estatística & dados numéricos , Pediatria/estatística & dados numéricos , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Tempo de Internação/estatística & dados numéricos , Polônia
16.
Wiad Lek ; 53(1-2): 4-21, 2000.
Artigo em Polonês | MEDLINE | ID: mdl-10806915

RESUMO

Hypertrophic cardiomyopathy (HCM) is phenotypically and genotypically heterogeneous disease of heart. Nine chromosomal loci responsible for this condition have been identified: beta-myosin heavy chain, essential and regulatory myosin light chains, troponin T and I subunits, alpha-tropomosin, cardiac myosin binding protein C, cardiac actin and titin. These genes code for proteins involved in the contraction mechanism or in the control of contraction, therefore HCM has been classified as a disease of cardiac sarcomere. Over 107 mutations have been identified. More then half of them have been detected in the beta-myosin heavy chain gene (beta-MHC). Some mutations in beta-MHC gene are associated with a benign prognosis, other are associated with high incidence of sudden cardiac death (SCD) and severe hypertrophy. Mutations in myosin binding protein C are associated with mild, delayed expression of cardiac hypertrophy and benign prognosis. Mutations in cardiac troponinT are associated with a mild degree of hypertrophy but a high incidence of SCD. Study of genes responsible for HCM will assume role in the context of clinical management of HCM, in particular regarding diagnosis and prognosis patients and families with HCM.


Assuntos
Cardiomiopatia Hipertrófica/diagnóstico , Cardiomiopatia Hipertrófica/genética , Expressão Gênica/genética , Humanos , Proteínas dos Microfilamentos/genética , Cadeias Pesadas de Miosina/genética , Mutação Puntual/genética , Prognóstico , Troponina I/genética , Troponina T/genética
17.
Drug Test Anal ; 4(9): 701-16, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22786790

RESUMO

Prenylamine is a vasodilator of phenylalkylamine structure and was used for the treatment of angina pectoris, until reports of undesirable effects including ventricular tachycardia led to a decreasing use of the drug in the 1980s. Metabolic N-dealkylation of orally ingested prenylamine can liberate amphetamine in humans and cause positive findings for amphetamine in doping and forensic analysis. In 2010, the World Anti-Doping Agency (WADA) classified prenylamine as a non-specified stimulant according to the 2010 Prohibited List, thus banning its use in sports in-competition. Supporting the development of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) based detection method, a post-administration urine sample following a single oral prenylamine ingestion (Segontin(®) 60 mg) was analyzed for urinary metabolites. The LC-separated analytes were ionized in positive electrospray ionization (ESI) mode and detected as protonated ions using an AB Sciex TripleTOF 5600 quadrupole-time-of-flight hybrid mass spectrometer. Over 40 phase I metabolites were detected, including previously unknown mono- bis-, tris- and tetra-hydroxylated prenylamine, several hydroxylated and methoxylated prenylamine metabolites and (hydroxylated) diphenylpropylamine. Investigation of the collision-induced dissociation behaviours of the metabolites by high resolution/high accuracy mass spectrometry allowed for the assignment of the nature and the site of observed metabolic transformations. The most abundant phase I metabolite was confirmed as p-hydroxy-prenlyamine by chemical synthesis and stable isotope labelling of reference material. An existing routine screening assay based on direct injection and LC-MS/MS analysis of urine was modified and validated according to common guidelines, in order to allow for the detection of p-hydroxy-prenylamine in sports drug testing. The assay demonstrated the ability to detect the target metabolite at 0.1 ng/ml at intra- and inter-day imprecisions below 10%.


Assuntos
Adrenérgicos/metabolismo , Adrenérgicos/urina , Prenilamina/metabolismo , Prenilamina/urina , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida/métodos , Dopagem Esportivo , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Detecção do Abuso de Substâncias/métodos , Vasodilatadores/metabolismo , Vasodilatadores/urina
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