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141.

Background  

Independent luciferase reporter assays and fluorescent translocation assays have been successfully used in drug discovery for several molecular targets. We developed U2transLUC, an assay system in which luciferase and fluorescent read-outs can be multiplexed to provide a powerful cell-based high content screening method.  相似文献   
142.
A series of metabolically stable adamantane amide 11beta-HSD1 inhibitors have been synthesized and biologically evaluated. These compounds exhibit excellent HSD1 potency and HSD2 selectivity and good pharmacokinetic and pharmacodynamic profiles.  相似文献   
143.

Background

Modified vaccinia virus Ankara (MVA), a highly attenuated strain of vaccinia virus, has been used as vaccine delivery vector in preclinical and clinical studies against infectious diseases and malignancies. Here, we investigated whether an MVA which does not encode any antigen (Ag) could be exploited as adjuvant per se.

Methodology/Principal Findings

We showed that dendritic cells infected in vitro with non-recombinant (nr) MVA expressed maturation and activation markers and were able to efficiently present exogenously pulsed Ag to T cells. In contrast to the dominant T helper (Th) 1 biased responses elicited against Ags produced by recombinant MVA vectors, the use of nrMVA as adjuvant for the co-administered soluble Ags resulted in a long lasting mixed Th1/Th2 responses.

Conclusions/Significance

These findings open new ways to potentiate and modulate the immune responses to vaccine Ags depending on whether they are co-administered with MVA or encoded by recombinant viruses.  相似文献   
144.
The skeleton of siliceous sponges consists of amorphous biogenous silica (biosilica). Biosilica formation is driven enzymatically by means of silicatein(s). During this unique process of enzymatic polycondensation, skeletal elements (spicules) that enfold a central proteinaceous structure (axial filament), mainly comprising silicatein, are formed. However, only the concerted action of silicatein and other proteins can explain the genetically controlled diversity of spicular morphotypes, from simple rods with pointed ends to intricate structures with up to six rays. With the scaffold protein silintaphin-1, a first silicatein interactor that facilitates the formation of the axial filament and, consequently, of the growing spicule was discovered. In this study, a new interactor has been identified by both a conventional yeast two-hybrid library screening and a newly established pull-down assay. For the latter approach, silicatein-α has been bioengineered to carry a Glu tag, which confers binding affinity to hydroxyapatite. After immobilization on a solid-phase matrix (hydroxyapatite), the Glu-tagged silicatein was used as bait for the identification of interactors. Both approaches revealed a 15 kDa polypeptide, and its identity was confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Colocalization of silintaphin-2 and silicatein-α within the axial filament and on the spicule surface was shown by immunohistological analyses. Subsequent autoradiography demonstrated the Ca(2+) binding affinity of this silicatein interactor. These findings indicate that both proteins operate in concert during spiculogenesis. Besides binding of calcium, silintaphin-2 shares several structural features with certain acidic, secreted extracellular matrix proteins that facilitate tissue mineralization in Metazoa. Hence, silintaphin-2 might mediate signal transduction during spiculogenesis or may play a more direct role during biosilica formation, in concert with silicatein.  相似文献   
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The degree to which fish diet differs by season and area, particularly over broad scales, was examined for the first time in temperate, contiguous north-west Atlantic Ocean waters by comparing food habit data for 10 species of fishes collected concurrently during the spring and autumn surveys in the U.S.A. (Gulf of Maine proper and Georges Bank) and in the summer survey in Canada (western Scotian Shelf and Bay of Fundy). For most species, there was a general concurrence among the three seasons and four areas: summer diets had the same dominant prey items as spring and autumn diets. Although a suite of multivariate analyses did elucidate some differences in specific proportions of the diet for these species across seasons and areas, the main prey did not substantially change for most of these species. These results suggest that there are (1) minimal differences in diet across season for these species at these taxonomic resolutions, (2) there are minimal differences in diet geographically for these species and (3) differences across species, as expected, are important. Many fisheries ecosystem and multispecies models are dependent on food habit data, where resolving seasonal and spatial differences in diet remains an important consideration; however, the present work implies that amalgamated estimates of diet from seasonal surveys may be a reasonable approach when no finer seasonal resolution exists, as long as due diligence is exercised.  相似文献   
147.
Determination of osteoporotic status is based primarily on areal bone mineral density (aBMD) obtained through dual X-ray absorptiometry (DXA). However, many fractures occur in patients with T-scores above the WHO threshold of osteoporosis, in part because DXA measures are insensitive to biomechanically important alterations in bone quality. The goal of this study was to determine--within groups of subjects with identical radius aBMD values--the extant variation in densitometric, geometric, microstructural, and biomechanical parameters. High resolution peripheral quantitative computed tomography (HR-pQCT) and DXA radius data from males and females spanning large ranges in age, osteoporotic status, and anthropometrics were compiled. 262 distal radius datasets were processed for this study. HR-pQCT scans were analyzed according to the manufacturer's standard clinical protocol to quantify densitometric, geometric, and microstructural indices. Micro-finite element analysis was performed to calculate biomechanical indices. Factor of risk of wrist fracture was calculated. Simulated aBMD calculated from HR-pQCT data was used to group scans for evaluation of variation in quantified indices. Indices reflecting the greatest variation within aBMD level were BMD in the central portion of the trabecular compartment (max CV 142), trabecular heterogeneity (max CV 90), and intra-cortical porosity (max CV 151). Of the biomechanical indices, cortical load fraction had the greatest variation (max CV 38). Substantial variations in indices reflecting density, structure, and biomechanical competence exist among subjects with identical aBMD levels. Overlap of these indices among osteoporotic status groups reflects the reported incidence of osteoporotic fracture in subjects classified as osteopenic or normal.  相似文献   
148.
Infections with Wuchereria bancrofti causing lymphatic filariasis still represent one of the major health problems in the tropics, with 120 million people infected and over 750 million exposed to this filarial parasite. We have studied lymphatic filariasis infections as part of a multi-parasite survey in a village community in the savannah of northern Nigeria. We analysed serum samples from 341 individuals aged 5-70 years, detecting a W. bancrofti circulating antigen using the commercially available ICT Filariasis card test. The prevalence of infections was 10% and clearly age-dependent, increasing from below 2% in children to over 20% in subjects older than 40 years. Measuring IgG4 antibodies against the recombinant W. bancrofti antigen SXP1 showed that 36% of all tested individuals had been at least exposed to the parasite. Antibody levels also increased very significantly with age. A further analysis measuring Onchocerca volvulus-specific IgG4 antibodies showed a very significant association between infections with O. volvulus and those with W. bancrofti. Our data show that infections with W. bancrofti in Nigeria are still a frequently occurring health problem, since they are more prevalent than previously reported, and that individuals with an O. volvulus infection are more often infected with W. bancrofti than expected statistically.  相似文献   
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