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1.
Cranio ; 36(6): 366-372, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28782462

RESUMEN

OBJECTIVES: The aim of this study was to identify a marker for temporomandibular joint (TMJ) osteoarthritis (OA) diagnosis by comparing the concentrations of urinary pyridinoline (PYD), deoxypyridinoline (DPD), and C-terminal telopeptides type I collagen (CTX-I), and CTX-II of TMJ OA patients with those of a non-symptomatic group. METHODS: PYD, DPD, CTX-I, and CTX-II concentrations in the urine of 36 non-symptomatic subjects and 31 TMJ OA subjects were analyzed. RESULTS: The differences for only PYD and DPD were significant. In ROC analysis, PYD and DPD showed higher sensitivity and specificity than CTX-I and CTX-II. PYD and DPD concentrations in urine were significantly increased in TMJ OA patients and can therefore be used as a biomarker in the supplementary clinical diagnosis of TMJ OA. DISCUSSION: The findings suggest that measurement of their concentration can be a supplementary method for clinical diagnosis of TMJ OA.


Asunto(s)
Aminoácidos/orina , Colágeno Tipo II/orina , Colágeno Tipo I/orina , Imidazoles/orina , Osteoartritis/diagnóstico , Trastornos de la Articulación Temporomandibular/diagnóstico , Adulto , Biomarcadores/orina , Femenino , Humanos , Masculino , Adulto Joven
2.
Mol Nutr Food Res ; 60(9): 1956-66, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27133590

RESUMEN

SCOPE: We previously showed that apiaceous but not cruciferous vegetables reduced DNA adducts formed by 2-amino-1-methyl-6-phenylimidazo[4, 5-b]pyridine (PhIP) in rats. Here, we report the effects of the putative chemopreventive phytochemicals from these vegetables on PhIP metabolism and DNA adduct formation. METHODS AND RESULTS: Rats received three supplemented diets: P + I (phenethyl isothiocyanate and indole-3-carbinol), furanocoumarins (FC, 5-methoxypsoralen, 8-methoxypsoralen, and isopimpinellin), and combination (P + I and FC). Phytochemical supplementation matched the levels in vegetables fed in our previous study. After 6 days, rats were injected with PhIP (10 mg/kg body wt) and killed after 24-h urine collection. Compared to the control, P + I increased activity of hepatic cytochrome P450 (CYP) 1A1 (10.1-fold), CYP1A2 (3.62-fold), and sulfotransferase 1A1 (2.70-fold). The combination diet also increased CYP1A1 and CYP1A2 activity. Urinary metabolomics revealed that PhIP metabolite profiles generally agreed with biotransformation enzyme activities. P + I and combination diets reduced PhIP-DNA adducts by 43.5 and 24.1%, respectively, whereas FC had no effect on adducts, compared to the control diet. CONCLUSION: Effects of phytochemicals on metabolic outcomes and markers of carcinogenesis might differ from fresh vegetables, thus limiting the inferences that one can draw from the effects of purified phytochemicals on the health benefits of the vegetables from which they derive.


Asunto(s)
Aductos de ADN/efectos de los fármacos , Furocumarinas/farmacología , Indoles/farmacología , Isotiocianatos/farmacología , Verduras/química , Animales , Anticarcinógenos/farmacología , Arilsulfotransferasa/metabolismo , Peso Corporal/efectos de los fármacos , Colon/efectos de los fármacos , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Suplementos Dietéticos , Glucuronosiltransferasa/metabolismo , Imidazoles/toxicidad , Imidazoles/orina , Masculino , Ratas Wistar
3.
Pharmacoepidemiol Drug Saf ; 25(4): 431-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26696520

RESUMEN

PURPOSE: Although sales of prescribed and over-the-counter (OTC) medication are rising, little is known about individual drug intake. This study was aimed to obtain complementary information about drug intake. METHOD: Information on drug utilization was obtained in a female cohort for five different time points (TP): 36th week of pregnancy (n = 622), 7th perinatal week (n = 533), 3rd perinatal month (n = 340), and 1st perinatal (n = 534) and 3rd perinatal year (n = 324) by a validated urine screening method. RESULTS: Drugs were detected 807 times among all analyzed samples (n = 2353) with less drug intake for early TP compared with later TP (~24.4%, n = 152; ~33.8%, n = 180; ~23.2%, n = 79; ~42.5%, n = 227; and ~52.2%, n = 169). The diversity of drugs increased from 25 up to 40 different drugs for the investigated period. OTC drugs were detected most frequently reflected by the top three drugs: acetaminophen (~37%, n = 292), ibuprofen (~23%, n = 183), and xylometazoline (~12%, n = 98). Mainly guideline-orientated drug therapy was observed. However, contraindicated ibuprofen intake during third trimester urine samples (n = 26) and a repeated usage of acetaminophen and/or ibuprofen (n = 9), as well as xylometazoline (n = 7), reveal missing information about drug safety. CONCLUSION: Bio monitoring was applied for detection of drug intake revealing a lack of information about OTC products and their health risks. Hence, information about health risks for certain drugs and patient groups must be improved for and by pharmacists, to avoid (i) usage of contraindicated drugs and (ii) abuse of OTC drugs.


Asunto(s)
Medicamentos sin Prescripción/administración & dosificación , Guías de Práctica Clínica como Asunto , Medicamentos bajo Prescripción/administración & dosificación , Urinálisis/métodos , Acetaminofén/administración & dosificación , Acetaminofén/orina , Contraindicaciones , Femenino , Humanos , Ibuprofeno/administración & dosificación , Ibuprofeno/orina , Imidazoles/administración & dosificación , Imidazoles/orina , Medicamentos sin Prescripción/análisis , Periodo Posparto , Embarazo , Medicamentos bajo Prescripción/análisis , Estudios Prospectivos , Factores de Tiempo
4.
Drug Metab Dispos ; 43(2): 190-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25384899

RESUMEN

A previous report from our laboratory disclosed the identification of PF-04991532 [(S)-6-(3-cyclopentyl-2-(4-trifluoromethyl)-1H-imidazol-1-yl)propanamido)nicotinic acid] as a hepatoselective glucokinase activator for the treatment of type 2 diabetes mellitus. Lack of in vitro metabolic turnover in microsomes and hepatocytes from preclinical species and humans suggested that metabolism would be inconsequential as a clearance mechanism of PF-04991532 in vivo. Qualitative examination of human circulating metabolites using plasma samples from a 14-day multiple ascending dose clinical study, however, revealed a glucuronide (M1) and monohydroxylation products (M2a and M2b/M2c) whose abundances (based on UV integration) were greater than 10% of the total drug-related material. Based on this preliminary observation, mass balance/excretion studies were triggered in animals, which revealed that the majority of circulating radioactivity following the oral administration of [¹4C]PF-04991532 was attributed to an unchanged parent (>70% in rats and dogs). In contrast with the human circulatory metabolite profile, the monohydroxylated metabolites were not detected in circulation in either rats or dogs. Available mass spectral evidence suggested that M2a and M2b/M2c were diastereomers derived from cyclopentyl ring oxidation in PF-04991532. Because cyclopentyl ring hydroxylation on the C-2 and C-3 positions can generate eight possible diastereomers, it was possible that additional diastereomers may have also formed and would need to be resolved from the M2a and M2b/M2c peaks observed in the current chromatography conditions. In conclusion, the human metabolite scouting study in tandem with the animal mass balance study allowed early identification of PF-04991532 oxidative metabolites, which were not predicted by in vitro methods and may require additional scrutiny in the development phase of PF-04991532.


Asunto(s)
Activadores de Enzimas/farmacocinética , Glucoquinasa/metabolismo , Hipoglucemiantes/farmacocinética , Imidazoles/farmacocinética , Hígado/efectos de los fármacos , Ácidos Nicotínicos/farmacocinética , Anciano , Animales , Animales Endogámicos , Biotransformación , Radioisótopos de Carbono , Perros , Evaluación Preclínica de Medicamentos , Activadores de Enzimas/análisis , Activadores de Enzimas/sangre , Activadores de Enzimas/orina , Heces/química , Femenino , Glucoquinasa/química , Semivida , Humanos , Hipoglucemiantes/análisis , Hipoglucemiantes/sangre , Hipoglucemiantes/orina , Imidazoles/análisis , Imidazoles/sangre , Imidazoles/orina , Hígado/enzimología , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Estructura Molecular , Ácidos Nicotínicos/análisis , Ácidos Nicotínicos/sangre , Ácidos Nicotínicos/orina , Especificidad de Órganos , Ratas Sprague-Dawley
5.
Toxicol Ind Health ; 29(2): 142-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22173956

RESUMEN

Doash (Origanum majorana) is an herbaceous plant found commonly in Saudi Arabia. It is used as a food flavor and a folk remedy to treat a number of diseases. The 2-amino-3-methylimidazo[4,5-f] quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) are the most abundant of the heterocyclic amine carcinogens present in cooked food. In the present study, the potential of doash tea to influence carcinogen metabolism was investigated indirectly using heterocyclic amines as model mutagens, IQ and PhIP. Results obtained showed that doash tea had no influence on body weight in both the studies. Rats were treated with different doses of IQ (1, 3, 5 and 10 mg/kg) or PhIP (1, 5, 10 and 20 mg/kg). The selected dosage was 5 mg/kg for both heterocyclic amines. Results obtained revealed that rats treated with doash tea and given a single dose of the heterocyclic amines, whether for 1 day (short-term) or for 1 month (long term), showed a statistically significant decrease in their excretion of indirect mutagens (IQ or PhIP). Following treatment of the rats with a single oral dose of IQ or PhIP, the highest mutagenic activity determined in the presence of an activation system was excreted in the urine after 24 h, with much lower levels of mutagencity being excreted during subsequent elimination from the body. No mutagenicity was observed in the absence of an activation system that is direct-acting mutagenicity using (IQ and PhIP). Statistical analysis revealed that, in comparison with the control group, the aqueous doash extract significantly reduced the mutagenic response after 24 h. It was concluded that doash extract significantly decreased the excretion of mutagens in comparison with the control group (water only).


Asunto(s)
Antimutagênicos/farmacología , Imidazoles/toxicidad , Mutágenos/toxicidad , Origanum/química , Extractos Vegetales/farmacología , Quinolinas/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Daño del ADN , Imidazoles/metabolismo , Imidazoles/orina , Masculino , Medicina Tradicional , Pruebas de Mutagenicidad , Mutágenos/metabolismo , Quinolinas/metabolismo , Quinolinas/orina , Ratas , Ratas Wistar , Proteína Ribosómica S9 , Proteínas Ribosómicas/metabolismo , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética
6.
J Clin Pharm Ther ; 27(3): 229-30, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12081638

RESUMEN

Paeoniae Radix (PR) is a commonly used traditional Chinese medicine. A slight effect of PR on the pharmacokinetics of phenytoin that is mainly metabolised by CYP2C9 has been reported. The aim of this pilot study was to clarify if PR has an effect on losartan oxidation used as a measure of CYP2C9 activity. Three healthy volunteers received a single oral dose of losartan before and after PR treatment. Losartan and E-3174, an active metabolite of losartan, were analysed in 8 hour urine. PR did not seem to have an effect on CYP2C9 activity when the losartan/E-3174 ratios were compared before and after PR treatment (P = 0.56) although a larger study would need to be undertaken to confirm this finding.


Asunto(s)
Sistema Enzimático del Citocromo P-450/metabolismo , Paeonia/química , Preparaciones de Plantas/farmacología , Interacciones Farmacológicas , Humanos , Imidazoles/orina , Losartán/administración & dosificación , Losartán/orina , Medicina Tradicional China , Fitoterapia , Tetrazoles/orina
7.
J Investig Dermatol Symp Proc ; 6(2): 143-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11764303

RESUMEN

Mastcytosis is a rare disease characterized by an abnormal increase of mast cells in tissues. The skin is the organ most frequently involved, but mast cells also accumulate in the bone marrow, gastrointestinal tract, lymph nodes, spleen, and liver. Recent studies suggest that activating mutations of c-kit, a protooncogene encoding for the receptor (kit) of stem cell factor, are a possible cause of some forms of mastocytosis. In addition, an increased rate of chromosomal aberrations has been found. Despite significant advances in research on mastocytosis, curative treatment is not yet available. Current management is based on avoidance of mediator-releasing triggers and symptomatic treatment.


Asunto(s)
Mastocitosis , Corticoesteroides/uso terapéutico , Adulto , Biopsia , Antagonistas de los Receptores Histamínicos H1/uso terapéutico , Antagonistas de los Receptores H2 de la Histamina/uso terapéutico , Humanos , Imidazoles/análisis , Imidazoles/orina , Factores Inmunológicos/uso terapéutico , Lactante , Interferón-alfa/uso terapéutico , Mastocitos/patología , Mastocitosis/diagnóstico , Mastocitosis/etiología , Mastocitosis/terapia , Mutación , Terapia PUVA/métodos , Pronóstico , Serina Endopeptidasas/análisis , Serina Endopeptidasas/sangre , Factor de Células Madre/genética , Triptasas
8.
Nutr Cancer ; 41(1-2): 98-103, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-12094635

RESUMEN

There is growing interest in the potential health benefits of tea, including the anticarcinogenic properties. We report here that white tea, the least processed form of tea, is a potent inhibitor of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)-induced colonic aberrant crypts in the rat. Male Fischer 344 rats were treated for 8 wk with white tea (2% wt/vol) or drinking water alone, and on alternating days in experimental Weeks 3 and 4 the animals were given PhIP (150 mg/kg body wt p.o.) or vehicle alone. At the end of the study there were 5.65 +/- 0.81 and 1.31 +/- 0.27 (SD) aberrant crypt foci per colon in groups given PhIP and PhIP + white tea, respectively (n = 12, P < 0.05). No changes were detected in N-acetyltransferase or arylsulfotransferase activities compared with controls, but there was marked induction of ethoxyresorufin O-deethylase, methoxyresorufin O-demethylase, and UDP-glucuronosyltransferase after treatment with white tea. Western blot revealed corresponding increases in cytochrome P-450 1A1 and 1A2 proteins. Enzyme assays and Western blot also revealed induction of glutathione S-transferase by white tea. There was less parent compound and 4'-hydroxy-PhIP but more PhIP-4'-O-glucuronide and PhIP-4'-O-sulfate in the urine from rats given PhIP + white tea than in urine from animals given carcinogen + drinking water. The results indicate that white tea inhibits PhIP-induced aberrant crypt foci by altering the expression of carcinogen-metabolizing enzymes, such that there is increased ring hydroxylation at the 4' position coupled with enhanced phase 2 conjugation.


Asunto(s)
Colon/patología , Neoplasias del Colon/prevención & control , Lesiones Precancerosas/prevención & control , , Animales , Anticarcinógenos/administración & dosificación , Neoplasias del Colon/inducido químicamente , Citocromo P-450 CYP1A1/biosíntesis , Citocromo P-450 CYP1A2/biosíntesis , Sistema Enzimático del Citocromo P-450/biosíntesis , Inducción Enzimática , Glucurónidos/orina , Glucuronosiltransferasa/biosíntesis , Glutatión Transferasa/biosíntesis , Imidazoles/orina , Masculino , Oxidorreductasas/biosíntesis , Ratas , Ratas Endogámicas F344 , Sulfatos/orina
9.
J Chromatogr ; 652(1): 67-72, 1994 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-8014229

RESUMEN

A high-performance liquid chromatographic method for the sensitive determination of 1-hydroxy-2-(imidazo[1,2-a]pyridin-3-yl)ethane-1, 1-bisphosphonic acid monohydrate (YM529) in plasma, urine and bone is described. Plasma obtained in high-dose animal studies is treated by method A, a simple method using 1 ml of plasma, which is based on deproteinization of plasma followed by coprecipitation of the drug with calcium phosphate and dissolution of the precipitate in EDTA. Plasma obtained in low-dose clinical studies is treated by method B, a more sensitive method using 4 ml of plasma, which is based on direct precipitation of the drug prior to the deproteinization in method A. Urine and bone samples are prepared by solid-phase extraction using a Sep-Pak C18 cartridge coupled with method A. The drug is separated with a reversed-phase column using a mobile phase at pH 7, and detected with a fluorescence detector following postcolumn alkalization of the mobile phase to enhance fluorescence intensity. The limit of determination is 0.2 ng/ml for method A and 0.05 ng/ml for method B in plasma, 0.05 ng/ml in urine, and 5 ng/g in bone.


Asunto(s)
Huesos/química , Difosfonatos/análisis , Imidazoles/análisis , Animales , Fosfatos de Calcio , Cromatografía Líquida de Alta Presión , Difosfonatos/sangre , Difosfonatos/orina , Perros , Ácido Edético , Humanos , Imidazoles/sangre , Imidazoles/orina , Indicadores y Reactivos , Ratas , Sensibilidad y Especificidad , Espectrometría de Fluorescencia
10.
Arch Dermatol Res ; 278(3): 228-31, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-2425755

RESUMEN

Chronic urticaria is a disease for which the available range of treatment modalities is limited. Ultraviolet radiation has recently been shown to affect histamine release from mast cells. We therefore studied the effects of PUVA and UVA on chronic urticaria. Nineteen patients took part in the study, which was designed as a randomized double-blind study. Eleven patients received PUVA, and 8 received UVA plus a placebo. In the PUVA group, 7 patients showed improvement, 3 noticed no change, and 1 became worse. In the group that received UVA plus placebo, 5 patients experienced an improvement, whereas the other 3 showed no change. The differences between the groups were not statistically significant. However, the probability of achieving this degree of improvement in both groups just by chance is less than 1%. Consequently, the improvement noted could have been due to either UVA alone or a placebo effect. It is concluded that PUVA is not better than UVA in the treatment of chronic urticaria.


Asunto(s)
Terapia PUVA , Terapia Ultravioleta , Urticaria/terapia , Adulto , Anciano , Enfermedad Crónica , Ensayos Clínicos como Asunto , Método Doble Ciego , Femenino , Liberación de Histamina/efectos de la radiación , Humanos , Imidazoles/orina , Masculino , Persona de Mediana Edad , Urticaria/tratamiento farmacológico , Urticaria/radioterapia
11.
Clin Chim Acta ; 121(3): 379-87, 1982 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-6955073

RESUMEN

N tau-Methylimidazoleacetic acid, the quantitatively most important metabolite of histamine, was isolated from urine by ion exchange chromatography. After esterification with 2-propanol and extraction, N tao-methylimidazoleacetic acid was analyzed by capillary gas chromatography with nitrogen-phosphorus detection, using N tao-ethylimidazoleacetic acid as internal standard. The synthesis of this internal standard is described. In contrast to the methods hitherto described, this method is appropriate for use in clinical chemical laboratories. Normal 24-h excretion ranged from 8.3 to 18.5 mumol (n = 20). Five patients with mastocytosis, a patient with chronic myelocytic leukemia and a patient after an anaphylactoid reaction on acetylsalicylic acid showed highly elevated values.


Asunto(s)
Cromatografía de Gases/métodos , Imidazoles/orina , 1-Propanol , Adulto , Anafilaxia/orina , Cromatografía por Intercambio Iónico , Esterificación , Histamina/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Leucemia Mieloide/orina , Nitrógeno/análisis , Fósforo/análisis , Urticaria Pigmentosa/orina
12.
J Invest Dermatol ; 76(1): 1-3, 1981 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7462662

RESUMEN

The effect of PUVA therapy on pruritus, the skin mast cell population and histamine metabolism has been studied in 3 patients with urticaria pigmentosa and manifestations of systemic mastocytosis. Relief of itch was found concomitant with a significant decrease of the major histamine metabolite 1-methyl-4-imidazoleacetic acid in the urine. The decrease occurred during the first 2 mo after starting PUVA therapy and was sustained during an observation period of 3 mo after discontinuation of the treatment. At this time a reduction of the number of mast cells was found in skin biopsy specimens. No evidence of acute histamine release in association with PUVA treatment was obtained. These results suggest that this effective new treatment for urticaria pigmentosa reduces the histamine turnover in the skin by inhibiting mast cell proliferation.


Asunto(s)
Histamina/metabolismo , Imidazoles/orina , Terapia PUVA , Fotoquimioterapia , Urticaria Pigmentosa/tratamiento farmacológico , Anciano , Femenino , Humanos , Masculino , Mastocitos/patología , Persona de Mediana Edad , Piel/patología , Urticaria Pigmentosa/orina
13.
J Nutr ; 110(3): 522-31, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6965714

RESUMEN

The capacity for tetrahydrofolate regeneration through folate-linked methionine synthesis and for purine-ring closure through formylation of aminoimidazole carboxamide ribotide was studied in pregnant female rats fed diets containing either methionine or homocystine with or without folic acid. Plasma and liver folates, serine transhydroxymethylase, 5,10-methylene tetrahydrofolate dehydrogenase and glutamate formiminotransferase activities were also assayed. Pregnancy proceeded normally in all groups. Hypotrophic fetuses were observed only with the diet containing homocystine and no folic acid. Plasma folates were severely depleted at the end of pregnancy even when folic acid was present in the diet. Hepatic stores of folate were twice as high in the methionine as in the homocystine-fed pregnant females supplemented with folic acid. This favorable effect of methionine was not observed in folic acid-deficient females. No change in levels of serine transhydroxymethylase, 5,10-methylenetetrahydrofolate dehydrogenase, glutamate formimino-transferase activities was observed. Pregnancy did not stimulate methionine synthetase activity, the level of which was primarily affected by the nutritional conditions. Because of its low output and narrow range of adaptativity, methionine synthetase cannot be the sole regulatory factor of THF regeneration. Urinary excretion of aminoimidazole carboxamide was enhanced in folic acid-deficient pregnant females and was not prevented by supplying methionine.


Asunto(s)
Aminoimidazol Carboxamida/orina , Ácido Fólico/metabolismo , Transferasas de Hidroximetilo y Formilo , Imidazoles/orina , Hígado/metabolismo , Metionina/biosíntesis , Preñez , 5-Metiltetrahidrofolato-Homocisteína S-Metiltransferasa/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Dieta , Femenino , Ácido Fólico/farmacología , Glutamato Formimidoiltransferasa , Glicina Hidroximetiltransferasa/metabolismo , Homocistina/farmacología , Metionina/farmacología , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Embarazo , Ratas , Tetrahidrofolatos/biosíntesis , Transferasas/metabolismo
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