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AIMS: To evaluate the clinical safety, tolerability, and pharmacokinetic and pharmacodynamic profile of the novel cannabinoid receptor-1 (CB1R) inverse agonist, INV-202, in adults with features of metabolic syndrome. MATERIALS AND METHODS: This was a multicentre, randomized, double-blind, placebo-controlled, 28-day repeat-dose (INV-202 [25 mg] or placebo, once-daily oral tablet), parallel-group study in 37 participants aged 18 to 65 years (46% female, mean age 55 years, glycated haemoglobin 5.7% [39 mmol/mol], body mass index [BMI] 38.1 kg/m2 ) with features of metabolic syndrome and glucose intolerance. An oral glucose tolerance test (OGTT) was performed at baseline and at the end of the study. Lipid profiles, weight, waist circumference and biomarkers were assessed weekly. Statistical comparisons were performed post hoc. RESULTS: INV-202 was well tolerated with no serious or severe treatment-emergent adverse events; the most common events related to known effects of CB1R blockade in the gastrointestinal tract. INV-202 produced a significant mean weight loss of 3.5 kg (3.3% compared with placebo participants who gained a mean 0.6 kg [0.5%]). INV-202 also exhibited significant reductions in waist circumference and BMI (P ≤ 0.03). There was no significant difference in OGTT 0- to 3-hour area under the curve for INV-202 versus placebo: least squares mean 29.38 versus 30.25 h*mmol/L, with an INV-202: placebo ratio of 97.1% (95% confidence interval 90.2, 105.6; P = 0.43). CONCLUSIONS: INV-202 was well tolerated, producing a signal for rapid weight loss with improvements in other metabolic syndrome markers in this population. These findings support further exploration and long-term assessment of cardiometabolic effects.
Assuntos
Diabetes Mellitus Tipo 2 , Síndrome Metabólica , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Síndrome Metabólica/tratamento farmacológico , Agonismo Inverso de Drogas , Hemoglobinas Glicadas , Teste de Tolerância a Glucose , Método Duplo-Cego , Redução de Peso , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Resultado do TratamentoRESUMO
ß2 -adrenergic agonists having the potential to be misused to enhance performance for their thermogenic and anabolic properties are prohibited in sports. Clenbuterol, ractopamine and zilpaterol are utilised legally or illegally as growth promoters of animals raised for their meat. No withdrawal times are imposed for ractopamine prior to slaughter; residues are detected in meat of treated animals, which constitutes a risk of inadvertent consumption. Insufficient information is available on the fate of ractopamine in humans to implement efficient detection in athletes' urine samples. We have developed a confirmation procedure for total ractopamine in urine following the enzymatic hydrolysis of glucuronides and sulphates and the conversion to tri-TMS derivative (limit of identification at 0.15 ng/ml). The sulphates were found to form between 85% to 97% of ractopamine excreted in athletes' urine samples analysed routinely or in volunteers following the administration of a micro-dose of 2.5 µg. Peak levels were reached at 2 to 6 h and decreased rapidly below 1 ng/ml 10 h after dosing. With one exception, the highest level estimated in athletes' samples was 1.2 ng/ml. Zilpaterol was confirmed in a few urine samples collected in the USA and Mexico (highest level 2 ng/ml), while hundreds of athletes' samples were reported to contain clenbuterol by our laboratory over the past 7 years. Most of these cases originated from Mexico (n = 102) and Guatemala (n = 119), often clustered in events during which multiple samples were collected, and for the vast majority, in levels lower than 0.2 ng/ml.
Assuntos
Clembuterol , Espectrometria de Massas em Tandem , Animais , Humanos , Espectrometria de Massas em Tandem/métodos , Clembuterol/análise , Agonistas Adrenérgicos beta/urina , Cromatografia Gasosa-Espectrometria de Massas , Fenetilaminas/análise , SulfatosRESUMO
Testosterone doping in sports is detected through the measurement of the carbon isotopic signature (δ13 C) of testosterone and its metabolites in urine. A critical step in achieving accurate and precise δ13 C values during compound-specific stable carbon isotope analysis (CSIA) is the removal of interfering matrix components. To this end, the World Anti-Doping Agency (WADA) recommends the use of high-performance liquid chromatography (HPLC) as a method of sample pretreatment. We provide a description of an automated two-dimensional HPLC (2D-HPLC) purification method for urine extracts that has made possible the CSIA of underivatized steroids, requiring only 36 min per sample. Eight urinary steroids including testosterone (T) and dehydroepiandrosterone (DHEA) and four of their metabolites as well as two endogenous reference compounds were collected during HPLC purification. Comparative GC chromatograms are used to contrast the efficiency of two-dimensional (2D) purification to a previously established 1D-HPLC method. The 2D purification leads to improved sample purity while simultaneously decreasing the analysis time, allowing for unprecedented sample throughput. Precision of δ13 C for all analyzed compounds in negative and positive controls was 0.5 or better, which is comparable with the precision of pure reference materials at similar intensities.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Desidroepiandrosterona/urina , Dopagem Esportivo/prevenção & controle , Testosterona/urina , Isótopos de Carbono/urina , Cromatografia Gasosa , Desidroepiandrosterona/metabolismo , Feminino , Humanos , Masculino , Testosterona/metabolismo , Fatores de TempoRESUMO
Interactions between organic matter and mineral matrices are critical to the preservation of soil and sediment organic matter. In addition to clay minerals, Fe(III) oxides particles have recently been shown to be responsible for the protection and burial of a large fraction of sedimentary organic carbon (OC). Through a combination of synchrotron X-ray techniques and high-resolution images of intact sediment particles, we assessed the mechanism of interaction between OC and iron, as well as the composition of organic matter co-localized with ferric iron. We present scanning transmission x-ray microscopy images at the Fe L3 and C K1 edges showing that the organic matter co-localized with Fe(III) consists primarily of C=C, C=O and C-OH functional groups. Coupling the co-localization results to iron K-edge X-ray absorption spectroscopy fitting results allowed to quantify the relative contribution of OC-complexed Fe to the total sediment iron and reactive iron pools, showing that 25-62% of total reactive iron is directly associated to OC through inner-sphere complexation in coastal sediments, as much as four times more than in low OC deep sea sediments. Direct inner-sphere complexation between OC and iron oxides (Fe-O-C) is responsible for transferring a large quantity of reduced OC to the sedimentary sink, which could otherwise be oxidized back to CO2.
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The biogeochemical cycles of iron and organic carbon are strongly interlinked. In oceanic waters, organic ligands have been shown to control the concentration of dissolved iron. In soils, solid iron phases shelter and preserve organic carbon, but the role of iron in the preservation of organic matter in sediments has not been clearly established. Here we use an iron reduction method previously applied to soils to determine the amount of organic carbon associated with reactive iron phases in sediments of various mineralogies collected from a wide range of depositional environments. Our findings suggest that 21.5 ± 8.6 per cent of the organic carbon in sediments is directly bound to reactive iron phases. We further estimate that a global mass of (19-45) × 10(15) grams of organic carbon is preserved in surface marine sediments as a result of its association with iron. We propose that these associations between organic carbon and iron, which are formed primarily through co-precipitation and/or direct chelation, promote the preservation of organic carbon in sediments. Because reactive iron phases are metastable over geological timescales, we suggest that they serve as an efficient 'rusty sink' for organic carbon, acting as a key factor in the long-term storage of organic carbon and thus contributing to the global cycles of carbon, oxygen and sulphur.
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Sedimentos Geológicos/química , Ferro/química , Compostos Orgânicos/química , Carbono/química , Carbono/metabolismo , Ciclo do Carbono , Isótopos de Carbono , Oxigênio/metabolismo , Enxofre/metabolismoRESUMO
Detection and quantification of the amorphous phase of etoricoxib bulk drug substances, a selective cycloogenase-2 inhibitor used for the treatment of osteoarthritis, rheumatoid arthritis, and dental pain, was carried out using modulated differential scanning calorimetry (MDSC), dynamic mechanical analysis (DMA), and Raman spectroscopy. Detection of amorphous content in pharmaceutical powders by DMA is a special application of dynamic mechanical spectroscopy. DMA was found to be a sensitive technique, able to detect the presence of an amorphous phase in a crystalline phase at concentrations as low as 0.5%. The limit of detection (LOD) determined for DMA was 2.5%. In comparison, Raman spectroscopy and MDSC had LOD values of 2% and 5% amorphous, respectively.