RESUMEN
Retinoic acid receptor related orphan receptor γt (RORγt), identified as the essential functional regulator of IL-17 producing Th17 cells, is an attractive drug target for treating autoimmune diseases. Starting from the reported GSK2981278 (Phase II), we structurally modified and synthesized a series of 2H-chromone-4-one based sulfonamide derivatives as novel RORγt inverse agonists, which significantly improved their human metabolic stabilities while maintaining a potent RORγt inverse agonist profile. Efforts in reducing the lipophilicity and improving the LLE values led to the discovery of c9, which demonstrated potent RORγt inverse agonistic activity and consistent metabolic stability. During in vivo studies, oral administration of compound c9 exhibited a robust and dose-dependent inhibition of IL-17A cytokine expression and significantly lessened the skin inflammatory symptoms in the mouse imiquimod-induced skin inflammation model. Docking analysis of the binding mode revealed that c9 can suitably occupy the active pocket, and the introduction of the morpholine pyridine group can interact with Leu396, His479, and Cys393. Thus, compound c9 was selected as a preclinical compound for treating Th17-driven autoimmune diseases.
Asunto(s)
Enfermedades Autoinmunes/tratamiento farmacológico , Cromonas/química , Inflamación/tratamiento farmacológico , Receptores de Ácido Retinoico/agonistas , Sulfonamidas/síntesis química , Secuencia de Aminoácidos , Animales , Modelos Animales de Enfermedad , Desarrollo de Medicamentos , Agonismo Inverso de Drogas , Femenino , Humanos , Imiquimod/metabolismo , Interleucina-17/metabolismo , Simulación del Acoplamiento Molecular , Unión Proteica , Conformación Proteica , Piranos/farmacología , Piranos/normas , Piel , Relación Estructura-Actividad , Sulfonamidas/administración & dosificación , Sulfonamidas/efectos adversos , Sulfonamidas/farmacocinética , Sulfonamidas/farmacología , Sulfonamidas/normas , Células Th17RESUMEN
A scallop midgut gland certified reference material, NMIJ CRM 7520-a, was developed for validation and quality assurance during the inspection of shellfish for diarrhetic shellfish toxins. The candidate material was prepared by using naturally-toxic and nontoxic boiled midgut glands spiked with okadaic acid (OA). The homogeneity and stability of the material were found to be appropriate. For the characterization of OA and dinophysistoxin-1 (DTX1), nine participants were involved in a co-laboratory study based on the Japanese Official Testing Method, where the compounds were assayed by liquid chromatography-tandem mass spectrometry following alkaline hydrolysis. The analytical values were obtained by the standard addition method with a standard spiking solution calibrated using the standard-solution certified reference materials OA and DTX1. The certified concentrations with expanded uncertainties (coverage factor kâ¯=â¯2, approximate 95% confidence interval) were determined to be (0.205⯱â¯0.061) mg/kg for OA and (0.45⯱â¯0.11) mg/kg for DTX1.
Asunto(s)
Diarrea/complicaciones , Toxinas Marinas/análisis , Pectinidae/química , Piranos/análisis , Mariscos/análisis , Animales , Calibración , Cromatografía Liquida , Humanos , Intestinos/química , Toxinas Marinas/normas , Toxinas Marinas/toxicidad , Ácido Ocadaico/análisis , Piranos/normas , Piranos/toxicidad , Estándares de Referencia , Intoxicación por Mariscos/complicaciones , Espectrometría de Masas en TándemRESUMEN
In June 2009, 11 outbreaks of food poisoning occurred in France, involving 45 individuals who had consumed mussels harvested in Vilaine Bay (Northwestern France). Because the toxic dinoflagellate Dinophysis spp. had been detected in the area from mid-May, okadaic acid (OA) and dinophysistoxins were suspected to be the cause of these outbreaks, although the weekly monitoring tests by mouse bioassay had been negative. With the help of the French reporting system for food-borne disease outbreaks, the detailed data on epidemiology, mussel consumption and complete product traceback, were collected for 11 individuals involved in three reported outbreaks. The batch of mussels identified as the source of these three outbreaks contained concentrations of toxins of the okadaic acid group that were approximately eight times higher than the European regulatory limit. Moreover, based on the consumption data available for the 11 cases, a lowest observable adverse effects level (LOAEL) was deduced. The LOAEL calculated from this study, although based on a very limited number of individuals, was in the same range, i.e. approximately 50 µg OA equivalents per person, as the LOAEL established by the European Food Safety Authority in 2006.
Asunto(s)
Bivalvos/química , Ácido Ocadaico/envenenamiento , Piranos/envenenamiento , Intoxicación por Mariscos/epidemiología , Adolescente , Adulto , Anciano , Animales , Niño , Cromatografía Liquida/métodos , Cromatografía Liquida/normas , Dinoflagelados/química , Femenino , Contaminación de Alimentos/análisis , Francia/epidemiología , Humanos , Masculino , Toxinas Marinas/análisis , Toxinas Marinas/envenenamiento , Toxinas Marinas/normas , Ratones , Persona de Mediana Edad , Ácido Ocadaico/normas , Piranos/normas , Estándares de Referencia , Espectrometría de Masas en Tándem/métodos , Espectrometría de Masas en Tándem/normas , Pruebas de Toxicidad , Adulto JovenRESUMEN
The state of the art of LC-MS of palytoxin and its analogues is reported in the present review. MS data for palytoxin, 42-hydroxy-palytoxin, ostreocin-D, mascarenotoxins, and ovatoxins, obtained using different ionization techniques, namely fast-atom bombardment (FAB), matrix assisted laser desorption ionization (MALDI), and electrospray ionization (ESI), are summarized together with the LC-MS methods used for their detection. Application of the developed LC-MS methods to both plankton and seafood analysis is also reported, paying attention to the extraction procedures used and to limits of detection (LOD) and quantitation (LOQ) achieved. In a research setting, LC-MS has shown a good potential in determination of palytoxin and its analogues from various sources, but, in a regulatory setting, routine LC-MS analysis of palytoxins is still at a preliminary stage. The LOQ currently achieved in seafood analysis appears insufficient to detect palytoxins in shellfish extract at levels close to the tolerance limit for palytoxins (30 µg/kg) proposed by the European Food Safety Authority (EFSA, 2009). In addition, lacking of certified reference standard of palytoxins as well as of validation studies for the proposed LC-MS methods represent important issues that should be faced for future perspectives of LC-MS technique.
Asunto(s)
Acrilamidas/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Cromatografía Liquida/métodos , Venenos de Cnidarios/química , Inocuidad de los Alimentos/métodos , Espectrometría de Masas/métodos , Piranos/química , Alimentos Marinos/análisis , Acrilamidas/normas , Compuestos Bicíclicos Heterocíclicos con Puentes/normas , Venenos de Cnidarios/normas , Límite de Detección , Estructura Molecular , Piranos/normas , Alimentos Marinos/normasRESUMEN
A sensitive and specific method was developed and validated for the determination of paeoniflorin in rat brain with liquid chromatography-tandem mass spectrometry. Sample pretreatment involved protein precipitation following solid-phase extraction. Paeoniflorin and geniposide (internal standard) were separated isocratically on a Waters Symmetry C18 column (150 mm x 2.1 mm i.d., 5 microm), using a mobile phase of methanol/water with 0.1% formic acid (50:50, v/v) at a flow-rate of 200-300 microL/min in 4min. A Finngan LTQ tandem mass spectrometer equipped with electrospray ionization source was operated in the positive ion mode. Selective reaction monitoring was performed to quantify paeoniflorin and the internal standard at m/z transitions of 503-->381 and 411-->231, respectively. A good linearity was found in the range of 2-500 ng/mL (R(2)=0.9939). The intra- and inter-batch assay precisions (coefficient of variation, CV) at 5, 50 and 400 ng/mL (n=5) ranged from 6.3% to 9.7% and 1.2% to 7.2%, respectively, and the accuracies were from 95.9% to 101.6% and 99.4% to 102.9%, respectively. The mean recoveries of paeoniflorin were 81.2%, 80.9% and 82.3% at 5, 50 and 400 ng/mL (n=5), respectively, and the mean recovery of the internal standard was 76.7% with a concentration of 50 ng/mL (n=5). Stability studies showed that paeoniflorin was stable in different conditions. Finally, the method was successfully applied to the pharmacokinetic study of paeoniflorin in rat brain following a single subcutaneous administration (10 mg/kg) to rats.
Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Benzoatos/análisis , Química Encefálica , Hidrocarburos Aromáticos con Puentes/análisis , Cromatografía Liquida/normas , Medicamentos Herbarios Chinos/análisis , Glucósidos/análisis , Espectrometría de Masas en Tándem/normas , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacocinética , Benzoatos/química , Benzoatos/farmacocinética , Encéfalo/metabolismo , Hidrocarburos Aromáticos con Puentes/química , Hidrocarburos Aromáticos con Puentes/farmacocinética , Calibración , Cromatografía Liquida/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacocinética , Glucósidos/química , Glucósidos/farmacocinética , Inyecciones Subcutáneas , Iridoides/normas , Masculino , Estructura Molecular , Monoterpenos , Paeonia/química , Raíces de Plantas/química , Piranos/normas , Ratas , Ratas Sprague-Dawley , Estándares de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Extracción en Fase Sólida , Espectrometría de Masa por Ionización de Electrospray , Espectrometría de Masas en Tándem/métodos , Distribución TisularRESUMEN
The anticoccidial efficacies of semduramicin and salinomycin against five field isolates of Eimeria maxima in broiler chickens were compared in five trials. Uninfected, unmedicated; infected, unmedicated; infected, 25 ppm semduramicin; and infected, 66 ppm salinomycin treatments were assigned to battery cages using a randomized, complete block design. Two levels of inocula, 10(3) and 10(4) oocysts per bird, were used in each trial in the infected treatments, creating a total of seven treatments per trial. Each treatment consisted of five replicate cages of eight broiler cockerels each. Medications were given in the feed continuously for 7 d beginning 24 h before inoculation. Response variables measured included bird weight gain by pen, feed consumption, feed conversion, plasma carotenoid concentrations, and coccidial lesion score. By using two levels of inocula it was demonstrated that the efficacy of each anticoccidial was equal to or greater than 90% in controlling these E. maxima isolates. It was also demonstrated that 25 ppm semduramicin was more efficacious than 66 ppm salinomycin based on improvements in weight gain, feed conversion, plasma carotenoid concentrations, and coccidial lesion control.