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1.
Steroids ; 104: 196-202, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26463899

RESUMEN

Over the last few years, low levels of prednisolone have been reported in several cattle urine samples by a number of laboratories within the EU at an average concentration of 2.0 ng mL(-1). The occurrence of prednisolone residues together with increased levels of hydrocortisone and cortisone in urine and tissue samples of untreated animals seems to demonstrate that traces of this steroid can be produced endogenously during stressful situations. Therefore, the endogenous origin of prednisolone makes difficult to correlate positive samples to a potential illicit treatment. An experimental study was developed to investigate the presence of natural and synthetic glucocorticoids and to evaluate levels of excreted prednisolone following growth-promoting treatments. Urine samples from calves undergone oral treatment with prednisolone, alone and in association with dexamethasone, were analyzed by a LC-MS/MS method, validated according to the Commission Decision 2002/657/EC. We also investigated if urinary free 6ß-hydroxyhydrocortisone/hydrocortisone ratio could be a reliable biomarker of illicit treatment with prednisolone and dexamethasone in calves. Our data revealed that urinary levels of prednisolone after both oral prednisolone treatments, never exceeded the value of 1.1 ng mL(-1). Similar prednisolone levels were found in urine samples of untreated calves. Moreover the presence of 6ß-hydroxyhydrocortisone below the CCα value made possible to estimate the 6ß-hydroxyhydrocortisone/hydrocortisone ratio only in a very limited number of samples. Obtained data suggest that further criteria have to be considered to allow correct decisions about the urinary presence of prednisolone during control activities.


Asunto(s)
Productos Biológicos/orina , Glucocorticoides/orina , Prednisolona/farmacología , Administración Oral , Animales , Productos Biológicos/química , Bovinos , Glucocorticoides/química , Masculino , Prednisolona/administración & dosificación
2.
Molecules ; 20(4): 5329-45, 2015 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-25816077

RESUMEN

The illegal use of opiates and cocaine is a challenge world-wide, but some derivatives are also valuable pharmaceuticals. Reference samples of the active ingredients and their metabolites are needed both for controlling administration in the clinic and to detect drugs of abuse. Especially, (13)C-labeled compounds are useful for identification and quantification purposes by mass spectroscopic techniques, potentially increasing accuracy by minimizing ion alteration/suppression effects. Thus, the synthesis of [acetyl-(13)C4]heroin, [acetyl-(13)C4-methyl-(13)C]heroin, [acetyl-(13)C2-methyl-(13)C]6-acetylmorphine, [N-methyl-(13)C-O-metyl-(13)C]codeine and phenyl-(13)C6-labeled derivatives of cocaine, benzoylecgonine, norcocaine and cocaethylene was undertaken to provide such reference materials. The synthetic work has focused on identifying (13)C atom-efficient routes towards these derivatives. Therefore, the (13)C-labeled opiates and cocaine derivatives were made from the corresponding natural products.


Asunto(s)
Analgésicos Opioides/síntesis química , Productos Biológicos/análisis , Cocaína/análogos & derivados , Morfina/síntesis química , Urinálisis/normas , Analgésicos Opioides/química , Analgésicos Opioides/metabolismo , Analgésicos Opioides/orina , Productos Biológicos/orina , Espectroscopía de Resonancia Magnética con Carbono-13 , Cocaína/síntesis química , Codeína/síntesis química , Codeína/química , Heroína/síntesis química , Heroína/química , Humanos , Estructura Molecular , Morfina/química , Derivados de la Morfina/orina , Detección de Abuso de Sustancias/normas
3.
Nat Chem Biol ; 9(3): 160-2, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23314914

RESUMEN

We report the identification of a physiological receptor-volatile pair in the mouse olfactory system. By activity-guided fractionation of exocrine gland extracts and subsequent chemical analysis, (Z)-5-tetradecen-1-ol was identified as a natural ligand for a mouse odorant receptor. (Z)-5-tetradecen-1-ol is excreted into male mouse urine under androgen control and enhances urine attractiveness to female mice. This report is to our knowledge the first to describe natural product-based deorphanization of an odorant receptor.


Asunto(s)
Productos Biológicos/química , Productos Biológicos/metabolismo , Alcoholes Grasos/química , Alcoholes Grasos/metabolismo , Receptores Odorantes/metabolismo , Animales , Productos Biológicos/aislamiento & purificación , Productos Biológicos/orina , Glándulas Exocrinas/metabolismo , Alcoholes Grasos/aislamiento & purificación , Femenino , Ligandos , Masculino , Ratones , Ratones Endogámicos C57BL
4.
Food Chem Toxicol ; 49(2): 429-33, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21093523

RESUMEN

Antrodia cinnamomea (Ac) is a medicinal mushroom widely used for the treatment of abdominal pain, hypertension and hepatocellular carcinoma, but subchronic toxicity of this material has not yet been investigated. This present study was conducted to assess the 90-day oral toxicity of A. cinnamomea from submerged culture in male and female Sprague-Dawley (SD) rats. Eighty rats were divided into four groups, each consisting of ten male and ten female rats. Test articles were administered by oral gavage to rats at 3000, 2200 and 1500 mg/kg BW/day for 90 consecutive days and reverse osmosis water was used as control. All animals survived to the end of the study. During the experiment period, no abnormal changes were observed in clinical signs, body weight and ophthalmological examinations. No significant differences were found in urinalysis, hematology and serum biochemistry parameters between the treatment and control groups. Necropsy and histopathological examination indicated no treatment-related changes. According to the above results, the no-observed-adverse-effect level (NOAEL) of Antrodia cinnamomea is identified to be greater than 3000 mg/kg BW/day in Sprague-Dawley rats.


Asunto(s)
Antrodia/química , Productos Biológicos/toxicidad , Animales , Productos Biológicos/sangre , Productos Biológicos/química , Productos Biológicos/orina , Femenino , Masculino , Nivel sin Efectos Adversos Observados , Ratas , Ratas Sprague-Dawley , Caracteres Sexuales , Aumento de Peso
5.
Int J Immunopathol Pharmacol ; 22(3): 615-25, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19822078

RESUMEN

Monocyte chemoattractant protein-1 (MCP-1, CCL-2) binds to the Duffy antigen (DARC) on red blood cells, which act as a sink for several chemokines including MCP-1. In this study it is hypothesized that DARC may alter the pharmacokinetics of infused recombinant human MCP-1 (rhMCP-1). The primary aim of this first in man trial is to compare the pharmacokinetics of rhMCP-1 in Duffy positive and negative individuals. A randomized, double-blinded, placebo-controlled dose escalation trial was conducted on 36 healthy volunteers. Subjects received infusions of 0.02-2.0 microg/kg rhMCP-1 or placebo for one hour. RhMCP-1 displayed linear pharmacokinetics. Duffy negative individuals reached maximal plasma levels significantly earlier, but overall plasma concentration profiles were not altered. rhMCP-1 markedly increased monocyte counts, and estimated EC50 values were 10-fold higher in Duffy positive than in Duffy negative subjects. Increased monocyte counts were associated with decreased surface expression of intercellular adhesion molecule 1 (ICAM-1, CD54). In contrast, neither CCR-2 or CD11b expression, nor markers of platelet or endothelial activation, inflammation and coagulation were altered. RhMCP-1 is a highly selective chemoattractant for monocytes in humans. The Duffy antigen only minimally alters the pharmacokinetics of rhMCP-1 for doses up to 2 microg/kg.


Asunto(s)
Productos Biológicos/farmacocinética , Quimiocina CCL2/farmacocinética , Sistema del Grupo Sanguíneo Duffy/inmunología , Receptores de Superficie Celular/inmunología , Adolescente , Adulto , Productos Biológicos/administración & dosificación , Productos Biológicos/sangre , Productos Biológicos/orina , Biomarcadores/sangre , Coagulación Sanguínea/efectos de los fármacos , Plaquetas/efectos de los fármacos , Plaquetas/inmunología , Recuento de Células , Quimiocina CCL2/administración & dosificación , Quimiocina CCL2/efectos adversos , Quimiocina CCL2/sangre , Quimiocina CCL2/orina , Método Doble Ciego , Sistema del Grupo Sanguíneo Duffy/genética , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/inmunología , Genotipo , Humanos , Infusiones Intravenosas , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Monocitos/inmunología , Fenotipo , Receptores de Superficie Celular/genética , Proteínas Recombinantes/sangre , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/orina , Adulto Joven
6.
J Acupunct Meridian Stud ; 2(2): 159-64, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20633488

RESUMEN

OBJECTIVES: This study was performed to investigate the toxicity of Secretio Bufonis (SB) on male mice and assess its no-observed-adverse-effect-level (NOAEL). MATERIALS AND METHODS: After feeding an aqueous solution of SB extracts to mice for either 1 or 8 weeks, their blood and urine were assayed and their liver and kidney morphology examined. The numerical data was analyzed by the Mann-Whitney U-test and analysis of variance test. RESULTS: Mice administered SB in 50 mg/kg/day for 1 week had higher heart weights and higher aspartate transaminase activities; those administered SB in 0.01 and 0.05 mg/kg/day for 8 weeks had lower creatinine concentrations; and those administered SB in 0.5 mg/kg/day for 8 weeks had higher brain weights and higher blood urea nitrogen. CONCLUSIONS: The extracts of SB had cardiac toxicity in the short term and hepatotoxicity in the long term. The NOAEL of the extract was under 5 mg/kg/day for 1 week and under 0.25 mg/kg/day for 8 weeks.


Asunto(s)
Productos Biológicos/efectos adversos , Bufonidae , Medicina Tradicional China , Animales , Asia , Productos Biológicos/sangre , Productos Biológicos/orina , Riñón/anatomía & histología , Riñón/efectos de los fármacos , Hígado/anatomía & histología , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos ICR , Tamaño de los Órganos/efectos de los fármacos
8.
J Natl Cancer Inst ; 80(15): 1203-11, 1988 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-3138430

RESUMEN

Cell locomotion is an essential requirement for invasion and metastasis of malignant cells. We have previously described the characterization of a 50-kilodalton autocrine motility factor (AMF), a cytokine that stimulates motility in human tumor cells. In this study, we investigated the elaboration of this factor in vivo by human bladder carcinoma and in vitro by a cultured transitional cell carcinoma (TCC) of the bladder cell line T24P. Urine samples from patients with bladder cancer were assayed for their capacity to stimulate migration of tumor cells. Comparing all TCC cases (22 patients) with all nonmalignant diagnoses (27 patients), we found a statistically significant (P less than .001) difference in the motility values. Invasive TCC cases (15 patients) were significantly (P less than .002) higher in regard to motility values compared with noninvasive TCC cases (8 patients), including one case of carcinoma in situ. In follow-up screening studies evaluating TCC recurrence, the recurrent tumors (9 patients) were higher (P less than .001) in regard to motility values than the tumor-free cases (11 patients). Furthermore, T24P cells showed a dose-dependent motile response to their own serum-free conditioned medium as well as to the AMF present in the urine of TCC patients. This finding is consistent with the source of AMF in the urine of these patients being the cancer itself. An enzyme-linked immunosorbent assay (ELISA) for AMF was also developed. Values determined by ELISA correlated well with the motility values measured separately. These data support the potential usefulness of AMF as a urine marker for bladder TCC.


Asunto(s)
Productos Biológicos/orina , Biomarcadores de Tumor/orina , Carcinoma de Células Transicionales/orina , Proteínas de Neoplasias/orina , Neoplasias de la Vejiga Urinaria/orina , Adulto , Anciano , Carcinoma de Células Transicionales/patología , Movimiento Celular , Citocinas , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Glucosa-6-Fosfato Isomerasa , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Vejiga Urinaria/patología
9.
J Clin Invest ; 77(2): 456-64, 1986 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-3003159

RESUMEN

Secretion by tumor cells of circulating bone-resorbing factors may frequently underlie the hypercalcemia that occurs in patients with malignancy. Efforts to identify the responsible mediators have been hampered by a lack of available human tumor cell systems suitable for study of the pathogenesis of the humoral hypercalcemia syndrome. We have established a transitional-cell carcinoma (TCC) line in vitro from a patient with humoral hypercalcemia. These cells are tumorigenic and cause hypercalcemia in athymic nude mice. Culture medium conditioned by TCC cells contains potent bone-resorbing activity in vitro, the physical and biological properties of which are similar to those of bone-resorbing activity present in the original patient's urine. The bone-resorbing activity of the TCC factor is accompanied by increased prostaglandin release from bone and is blocked by indomethacin and calcitonin. The TCC-derived bone-resorbing activity coelutes with prostaglandin-stimulating activity during gel filtration with an approximate molecular weight of 15,000. This activity is nondialyzable, stable to concentrated urea and reducing agents, and destroyed by boiling. The TCC factor does not increase cyclic AMP production in bone or kidney bioassays and does not exhibit transforming growth factor activity. We conclude that a unique macromolecular factor released by TCC cells causes bone resorption by a mechanism dependent upon stimulation of bone cell cyclooxygenase, and that this factor is the probable cause of the hypercalcemia in vivo. The TCC cell line provides a new model for study of the human humoral hypercalcemia syndrome.


Asunto(s)
Productos Biológicos/metabolismo , Carcinoma de Células Transicionales/metabolismo , Citocinas , Hipercalcemia/etiología , Neoplasias de la Vejiga Urinaria/metabolismo , Animales , Bioensayo , Productos Biológicos/orina , Resorción Ósea/efectos de los fármacos , Calcitonina/farmacología , Carcinoma de Células Transicionales/complicaciones , Línea Celular , AMP Cíclico/metabolismo , Dinoprostona , Femenino , Humanos , Indometacina/farmacología , Ratones , Ratones Desnudos , Persona de Mediana Edad , Peso Molecular , Hormona Paratiroidea/farmacología , Prostaglandinas E/metabolismo , Neoplasias de la Vejiga Urinaria/complicaciones
11.
Immunopharmacology ; 2(1): 51-61, 1979 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-553082

RESUMEN

It has been suggested that the suppression of cell-mediated immune phenomena following niridazole administration is most likely due to a niridazole metabolite rather than the parent drug. This hypothesis was tested using two inbred strains of mice that manifest different rates of microsomal niridazole oxidation and reduction. DBA/2J mice were found to metabolize niridazole at a rate approximately 3-fold greater than C57BL/6J mice under both aerobic and anaerobic conditions. Niridazole was found to be more potent with respect to suppression of cutaneous delayed hypersensitivity in the former than in the latter. An immunosuppressive component was isolated from the urine fraction obtained from niridazole-treated rats. This component was found to be chromatographically pure; have a simple UV absorbance spectrum containing no 360 nm absorbing material characteristic of niridazole; to show no strain difference with respect to potency or efficacy in the ear-swelling assay for cutaneous delayed hypersensitivity; and to be 10(7) times more potent than niridazole with respect to the suppression of cutaneous delayed hypersensitivity.


Asunto(s)
Productos Biológicos/farmacología , Hipersensibilidad Tardía/tratamiento farmacológico , Ratones Endogámicos C57BL/metabolismo , Ratones Endogámicos DBA/metabolismo , Niridazol/farmacología , Animales , Productos Biológicos/orina , Humanos , Tolerancia Inmunológica , Masculino , Ratones , Microsomas Hepáticos/metabolismo , Niridazol/metabolismo , Niridazol/orina , Ratas
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