RESUMO
The polarization-maintaining fiber-based Sagnac loop interferometer (PSLI) is frequently applied in directional torsion measurement, but may suffer from a large temperature cross talk. In this study, a novel method was proposed for fabrication of side-tapered PSLI by a two-step arc-discharge technique at the splicing point. The energy distribution of the taper region was characterized, and comprehensive tests were performed in terms of torsion and temperature. The experimental results showed that, through bias twisting, the measuring areas were effectively gapped and highly sensitive torsion and temperature responses were gained simultaneously. With a small wavelength shift, the torsion sensitivity reached 13.54 dB/rad in the range from -30 to 30 rad/m. Moreover, the temperature sensitivity was found to be -1.579nm/∘C, with a near-zero intensity fluctuation. Therefore, the sensor fabricated herein successfully achieves simultaneous measurement of directional torsion and temperature with high sensitivity and ultralow cross talk. The proposed scheme has the merits of practicality, low cost, and ease of operation, and is very promising for multiparameter engineering monitoring.
RESUMO
Small vessel vasculitis is a life-threatening condition and patients typically present with renal and pulmonary injury. Disease pathogenesis is associated with neutrophil accumulation, activation, and oxidative damage, the latter being driven in large part by myeloperoxidase (MPO), which generates hypochlorous acid among other oxidants. MPO has been associated with vasculitis, disseminated vascular inflammation typically involving pulmonary and renal microvasculature and often resulting in critical consequences. MPO contributes to vascular injury by 1) catabolizing nitric oxide, impairing vasomotor function; 2) causing oxidative damage to lipoproteins and endothelial cells, leading to atherosclerosis; and 3) stimulating formation of neutrophil extracellular traps, resulting in vessel occlusion and thrombosis. Here we report a selective 2-thiouracil mechanism-based MPO inhibitor (PF-1355 [2-(6-(2,5-dimethoxyphenyl)-4-oxo-2-thioxo-3,4-dihydropyrimidin-1(2H)-yl)acetamide) and demonstrate that MPO is a critical mediator of vasculitis in mouse disease models. A pharmacokinetic/pharmacodynamic response model of PF-1355 exposure in relation with MPO activity was derived from mouse peritonitis. The contribution of MPO activity to vasculitis was then examined in an immune complex model of pulmonary disease. Oral administration of PF-1355 reduced plasma MPO activity, vascular edema, neutrophil recruitment, and elevated circulating cytokines. In a model of anti-glomerular basement membrane disease, formerly known as Goodpasture disease, albuminuria and chronic renal dysfunction were completely suppressed by PF-1355 treatment. This study shows that MPO activity is critical in driving immune complex vasculitis and provides confidence in testing the hypothesis that MPO inhibition will provide benefit in treating human vasculitic diseases.
Assuntos
Acetamidas/farmacologia , Inibidores Enzimáticos/farmacologia , Membrana Basal Glomerular/efeitos dos fármacos , Glomerulonefrite/prevenção & controle , Doenças do Complexo Imune/prevenção & controle , Peroxidase/antagonistas & inibidores , Pirimidinas/farmacologia , Pirimidinonas/farmacologia , Vasculite/prevenção & controle , Animais , Membrana Basal Glomerular/patologia , Glomerulonefrite/enzimologia , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Humanos , Doenças do Complexo Imune/enzimologia , Doenças do Complexo Imune/imunologia , Doenças do Complexo Imune/patologia , Pulmão/irrigação sanguínea , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos , Infiltração de Neutrófilos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Vasculite/enzimologia , Vasculite/imunologia , Vasculite/patologiaRESUMO
We describe the design, synthesis, and structure-activity relationships of triazolobenzodiazepinone CCK1 receptor agonists. Analogs in this series demonstrate potent agonist activity as measured by in vitro and in vivo assays for CCK1 agonism. Our efforts resulted in the identification of compound 4a which significantly reduced food intake with minimal systemic exposure in rodents.
Assuntos
Fármacos Antiobesidade/farmacologia , Benzodiazepinas/farmacologia , Receptores da Colecistocinina/agonistas , Animais , Fármacos Antiobesidade/farmacocinética , Benzodiazepinas/química , Benzodiazepinas/farmacocinética , Masculino , Ratos , Ratos Sprague-Dawley , Relação Estrutura-AtividadeRESUMO
We evaluated the in vitro pharmacological profile of a novel, potent and highly selective Na(+)/H(+) exchanger-1 (NHE-1) inhibitor, [1-(Quinolin-5-yl)-5-cyclopropyl-1H-pyrazole-4-carbonyl]guanidine hydrochloride monohydrate (zoniporide or CP-597,396). The potency and selectivity of zoniporide were determined via inhibition of 22Na(+) uptake by PS-120 fibroblast cell lines overexpressing human NHE-1, -2 or rat NHE-3. Additionally, potency for endogenous NHE-1 was confirmed via ex vivo human platelet swelling assay (PSA), in which platelet swelling was induced by exposure to sodium propionate. The pharmacological profile of zoniporide was compared with that of eniporide and cariporide. Zoniporide inhibited 22Na(+) uptake in fibroblasts expressing human NHE-1 in a concentration-dependent manner (IC(50) = 14 nM) and was highly selective (157-fold and 15,700-fold vs. human NHE-2 and rat NHE-3, respectively). Zoniporide was 1.64- to 2.6-fold more potent at human NHE-1 than either eniporide or cariporide (IC(50) = 23 and 36 nM, respectively). Zoniporide was also more selective at inhibiting human NHE-1 vs. human NHE-2 than either eniporide or cariporide (157-fold selective compared with 27- and 49-fold, respectively). All three compounds inhibited human platelet swelling with IC(50) values in low nanomolar range. From these results, we conclude that zoniporide represents a novel, potent and highly selective NHE-1 inhibitor.