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Lee BC Kim JS Kim BS Son JY Hong SK Park HS Moon BS Jung JH Jeong JM Kim SE 《Bioorganic & medicinal chemistry》2011,19(9):2980-2990
To develop agents for radionuclide imaging Aβ plaques in vivo, we prepared three fluorine-substituted analogs of arylbenzothiazole class; compound 2 has a high affinity for Aβ (K(i)=5.5nM) and the specific binding to Aβ in fluorescent staining. In preparation for the synthesis of these arylbenzothiazole analogs in radiolabeled form as an Aβ plaques-specific positron emission tomography (PET) imaging probe, we investigated synthetic route suitable for its labeling with the short-lived PET radionuclide fluorine-18 (t(1/2)=110min) and diaryliodonium tosylate precursors (12, 13a-e and 14). 2-Aryl-6-[(18)F]fluorobenzothiazoles ([(18)F]1-3) were synthesized in efficiently short reaction times (40-60min) with high radiochemical yields (19-40%), purities (>95%) and specific activities (85-118GBq/μmol). Tissue distribution studies showed that high radioactivity of [(18)F]2 accumulated in the brain with rapid clearance in healthy mice. Radioactive metabolites were analyzed in brain samples of mice and corresponded to 81% of parent remained by 30min after a tail-vein injection. These results suggest that [(18)F]2 is a promising probe for evaluation of Aβ plaques imaging in brain using PET. 相似文献
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In healthy subjects, pharmacokinetics were characterised using single oral and sublingual administrations of the beta-carboline norharman. For this purpose, norharman levels in blood plasma were measured up to 90-105 min after both routes of administration. Dose proportionality of three different single oral doses of norharman (7, 65 and 110 microg/kg) administered as 0.52 and 5 mg capsules was evaluated at 8 time points. Peak levels were attained at 30 min after the oral load of norharman. Mean relative availabilities determined by the area under the curve (AUC) procedure were 14.3 and 98.0 nmol.min/l after oral dosing of 7 and 65 microg/kg, respectively. AUC values in women were 3-4 times higher than in men. Sublingual dosing of 6.5 and 13 microg/kg norharman encapsulated in 5 mg of cyclodextrins resulted in a much higher mean AUC and a more rapid absorption. Mean AUC after sublingual administration of 6.5 microg/kg was 929.8 nmol.min/kg and plasma levels were maximal 10-15 min after norharman was given. Moreover, apparently no sex difference was found using this way of application. Norharman disappeared from the plasma with half-lifes of 25-35 min, irrespective of the route of administration. Even at the highest measured norharman levels of 53 nmol/l plasma, no behavioral effects were observed. In addition, the subjects did neither report any effects nor any side-effects during the experiment. This is the first study in which the kinetics of ingested norharman have been measured in humans. 相似文献
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From sensor data to animal behaviour: an oystercatcher example 总被引:1,自引:0,他引:1
Animal-borne sensors enable researchers to remotely track animals, their physiological state and body movements. Accelerometers, for example, have been used in several studies to measure body movement, posture, and energy expenditure, although predominantly in marine animals. In many studies, behaviour is often inferred from expert interpretation of sensor data and not validated with direct observations of the animal. The aim of this study was to derive models that could be used to classify oystercatcher (Haematopus ostralegus) behaviour based on sensor data. We measured the location, speed, and tri-axial acceleration of three oystercatchers using a flexible GPS tracking system and conducted simultaneous visual observations of the behaviour of these birds in their natural environment. We then used these data to develop three supervised classification trees of behaviour and finally applied one of the models to calculate time-activity budgets. The model based on accelerometer data developed to classify three behaviours (fly, terrestrial locomotion, and no movement) was much more accurate (cross-validation error?=?0.14) than the model based on GPS-speed alone (cross-validation error?=?0.35). The most parsimonious acceleration model designed to classify eight behaviours could distinguish five: fly, forage, body care, stand, and sit (cross-validation error?=?0.28); other behaviours that were observed, such as aggression or handling of prey, could not be distinguished. Model limitations and potential improvements are discussed. The workflow design presented in this study can facilitate model development, be adapted to a wide range of species, and together with the appropriate measurements, can foster the study of behaviour and habitat use of free living animals throughout their annual routine. 相似文献
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CRP has a graded, dose-response relationship to the occurrence of clinical cardiovascular events that remains after adjustment for other risk factors, with moderately strong associations between the lower and upper tertiles (RR≈2). It may have clinical utility in improving the estimation of absolute risks of patients with a calculated ten-year risk between 10 and 20%. Individuals at low risk (<10% per 10 years) will be unlikely to have a high risk identified through CRP testing. Additional prospective studies or new statistical analysis of previous studies are needed to establish the added predictive value of CRP above that of currently established risk factors. Thus, currently available evidence suggests that CRP testing should not be ordered along with lipid profiles. 相似文献
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Andréia Pelegrini Juliana Possatto Takahashi Carolina de Queiroz Moreira Pereira Rosemeire Bom Pessoni Marta Cristina Souza 《Revista iberoamericana de micología》2009,26(2):118-120
The incidence of cases of dermatophytosis in dermatology outpatient departments has increased in recent years. Infection control is essential to prevent transmission, and accurate diagnosis of this type of infection is important to avoid confusion with other dermatological processes caused by non-fungal agents. The objective of this study was to determine the incidence of dermatophytosis and its etiological agents in a public hospital of São Bernardo do Campo, Brazil. From February 2005 to May 2006, 273 samples were collected from 191 patients in a public dermatology outpatient department. The samples were collected according to conventional methods used in clinical mycology and direct examinations and cultures were performed. Of the samples suspected of fungal infection, 19% produced positive cultures, and the largest number of samples was from female patients between 31 and 40 years old. The most commonly infected area was the toenails, and the most common infective agents according to microscopic analysis and biochemical tests were the Candida species, which were responsible for 61.6% of the infections. These data agree with findings reported in the literature indicating a lower prevalence of filamentous fungi, such as Epidermophyton, Trichophyton, and Microsporum, in dermatomycosis. 相似文献
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Gangliosides, sialic acid-containing glycosphingolipids, are implicated in many neuronal diseases, but the precise molecular mechanisms underlying their pathological activities are poorly understood. Here we report that TLR2 participates in the initiation of ganglioside-triggered inflammatory signaling responses. Using FACS analysis and immunofluorescence microscopy, we found that gangliosides rapidly enhanced the cell surface expression of TLR2 in microglia, while reducing that of TLR4. The ganglioside-dependent increase of TLR2 expression was also observed at the messenger and protein levels. We also showed that gangliosides stimulate the interaction of TLR2 with Myd88, an adaptor for TLRs, and obtained evidence that lipid raft formation is closely associated with the ganglioside-induced activation of TLR2 and subsequent inflammatory signaling. These results collectively suggest that TLR2 contributes to the ability of gangliosides to cause inflammatory conditions in the brain. 相似文献
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Food web consequences of an evolutionary arms race: Molluscs subject to crab predation on intertidal mudflats in Oman are unavailable to shorebirds 下载免费PDF全文
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Bom A Booth S Bruin J Clark J Miller S Wathey B 《Bioorganic & medicinal chemistry letters》2001,11(17):2351-2354
The first solid-phase synthesis of zatebradine 1 and its analogues is reported. This has resulted in the preparation of compounds with increased ability to reduce the spontaneous beating of isolated guinea-pig atria in a concentration-dependent manner. One example, 8g, showed a maximum reduction of beating of 80% at 3 microM compared to a reduction of 40% at 3 microM with zatebradine 1. 相似文献
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Reinier J. M. Bom Jannie J. van der Helm Maarten F. Schim van der Loeff Martijn S. van Rooijen Titia Heijman Amy Matser Henry J. C. de Vries Sylvia M. Bruisten 《PloS one》2013,8(1)