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51.
Compounds that simultaneously activate peroxisome proliferator‐activated receptor (PPAR) subtypes α and γ have the potential to effectively treat dyslipidemia and type 2 diabetes (T2D) in a single pharmaceutically active molecule. The frequently observed side effects of selective PPARγ agonists, such as edema and weight gain, were expected to be overcome by using additive PPARα activity, leading to dual PPARα/γ agonists with balanced activity for both subtypes. Herein we report the discovery, synthesis, and optimization of a new series of α‐ethoxyphenylpropionic acid bearing 5‐ or 6‐substituted indoles. The incorporation of oxime ethers on the carbonyl portion of the benzoyl group can bring the PPARα/γ potency ratio equal to or slightly greater than one, as is the case for compounds 20 c and 21 a . Compound 20 c shows high efficacy in an ob/ob mouse model of T2D and dyslipidemia, similar to that of rosiglitazone and tesaglitazar, but with a significant increase in body weight gain. In contrast, compound 21 a , less potent as a dual PPARα/γ activator than 20 c , showed an interesting pharmacological profile, as it elicits a decrease in body weight relative to reference compounds.  相似文献   
52.
The physic nut shrub, Jatropha curcas (Euphorbiaceae), has been considered as a “miracle tree”, particularly as a source of alternate fuel. Various extracts of the plant have been reported to have insecticidal/acaricidal or molluscicidal/anthelminthic activities on vectors of medical or veterinary interest or on agricultural or non-agricultural pests. Among those extracts, the phorbol ester fraction from seed oil has been reported as a promising candidate for use as a plant-derived protectant of a variety of crops, from a range of pre-harvest and post-harvest insect pests. However, such extracts have not been widely used, despite the “boom” in the development of the crop in the tropics during recent years, and societal concerns about overuse of systemic chemical pesticides. There are many potential explanations to such a lack of use of Jatropha insecticidal extracts. On the one hand, the application of extracts potentially harmful to human health on stored food grain, might not be relevant. The problem of decomposition of phorbol esters and other compounds toxic to crop pests in the field needing further evaluation before such extracts can be widely used, may also be a partial explanation. High variability of phorbol ester content and hence of insecticidal activity among physic nut cultivars/ecotypes may be another. Phytotoxicity to crops may be further limitation. Apparent obstacles to a wider application of such extracts are the costs and problems involved with registration and legal approval. On the other hand, more studies should be conducted on molluscicidal activity on slugs and land snails which are major pests of crops, particularly in conservation agriculture systems. Further evaluation of toxicity to natural enemies of insect pests and studies on other beneficial insects such as pollinators are also needed.  相似文献   
53.
Microbial transglutaminase (MTG) was stably solid‐phase immobilized on glass microbeads by using a second‐generation dendronized polymer. Immobilized MTG enabled the efficient generation of site‐specifically conjugated proteins, including antibody fragments, as well as whole antibodies through distinct glutamines and, unprecedentedly, also through lysines with various bifunctional substrates with defined stoichiometries. With this method, we generated dual, site‐specifically modified antibodies comprising a fluorescent probe and a metal chelator for radiolabeling—a strategy anticipated to design antibodies for imaging and simultaneous therapy. Furthermore, we provide evidence that immobilized MTG features higher siteselectivity than soluble MTG.  相似文献   
54.
The effect of ultraviolet (UV) irradiation on a multilayer film made of poly(ethylene terephthalate)/Polyamide 6/poly(ethylene terephthalate) was investigated by uniaxial tractions, UV‐visible‐NIR and Fourier transformed infra‐red‐attenuated total reflection spectroscopy, differential scanning calorimetry ( DSC), and dynamic dielectric spectroscopy (DDS). The multilayer was exposed to ultraviolet radiations (filtered at 270 nm) for 7 days, in air. The complexity of the multilayer thermograms recorded by DSC and DDS has required the study of each film constituting the multilayer to assess each the contribution of each one of them. A deterioration in mechanical properties and a decrease in UV transmission for low wavelengths are observed. These evolutions seem to result to the photo‐oxidation of the poly(ethylene terephthalate) film mainly localized at the exposed layer. This layer acts as a UV protection filter for the other layers. However, the DDS analyses show a plasticization effect of the primary mode in the Polyamide 6, which is evidence of photo‐oxidation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
55.
While now recognized as an aid to predict repeat prostate biopsy outcome, the urinary PCA3 (prostate cancer gene 3) test has also been recently advocated to predict initial biopsy results. The objective is to evaluate the performance of the PCA3 test in predicting results of initial prostate biopsies and to determine whether its incorporation into specific nomograms reinforces its diagnostic value. A prospective study included 601 consecutive patients addressed for initial prostate biopsy. The PCA3 test was performed before ≥12-core initial prostate biopsy, along with standard risk factor assessment. Diagnostic performance of the PCA3 test was evaluated. The three available nomograms (Hansen’s and Chun’s nomograms, as well as the updated Prostate Cancer Prevention Trial risk calculator; PCPT) were applied to the cohort, and their predictive accuracies were assessed in terms of biopsy outcome: the presence of any prostate cancer (PCa) and high-grade prostate cancer (HGPCa). The PCA3 score provided significant predictive accuracy. While the PCPT risk calculator appeared less accurate; both Chun’s and Hansen’s nomograms provided good calibration and high net benefit on decision curve analyses. When applying nomogram-derived PCa probability thresholds ≤30%, ≤6% of HGPCa would have been missed, while avoiding up to 48% of unnecessary biopsies. The urinary PCA3 test and PCA3-incorporating nomograms can be considered as reliable tools to aid in the initial biopsy decision.  相似文献   
56.
The anisotropic fracture behavior in unpoled and poled (1− x )Pb(Zn2/3Nb1/3)− x PbTiO3 ( x =0.045) (PZN–4.5%PT) single-crystal relaxor ferroelectrics cut along the crystal planes, [010] and [001], was characterized. The crack tip toughness ( K tip) determined from Vickers indentations was compared with the R -curve behavior measured using the single-edge V-notch beam (SEVNB) method. Several of the SEVNB fracture experiments resulted in cracks forming and propagating under mixed mode loading ( K I and K II) along the [110] crystal plane. Other specimens formed cracks at 0° along the [010] plane. To assess the anisotropic fracture behavior, the local and global critical energy release rates were determined using Stroh's formalism.  相似文献   
57.
The cytostatic activities of a series of twelve 1,10-phenanthroline (Phen) derivatives and of their copper complexes were studied on L1210 murine leukemia cells. Large increases in the biological activity were observed for compounds of the 3-Clip-Phen series, in which two Phen moieties were bridged at their C3 positions by an alkoxy linker, the 3-pentyl-Clip-Phen derivative showing an IC(50) value of 130 nM while Phen shows an IC(50) value of 2500 nM under the same conditions. IC(50) values seemed to be modulated not only by the position, the nature, and the length of the linker of Clip-Phen but also by hydrophobicity. Since copper complexes of Phen are chemical nucleases and nucleic acids are thus a potential target for these compounds, the corresponding copper complexes were also studied. Copper complexation of the 3-Clip-Phen ligands did not increase their biological activities. Attempts to vectorize 3-Clip-Phen derivatives with a DNA binder such as spermine or with a cell-penetration peptide failed to increase their biological activity relative to the original 3-Clip-Phen series.  相似文献   
58.
In this study, YSZ coatings were deposited on different substrate materials (stainless steel and aluminum) using suspension plasma spray technique. The effects of substrate properties (material, surface topology, temperature, and thickness) on the formation of coatings were investigated. The results showed that, with the identical spray parameters, the porosity is higher for the coatings deposited on aluminum than that on stainless steel due to the high thermal transfer ability of the former substrate material. The SEM results revealed that the microstructure of as-prepared coatings could be tailored from the vertical cracked structure to the columnar structure by increasing the substrate surface roughness and their formation mechanisms were discussed. The substrate preheating temperature has an influence on the microstructure of the coatings, especially in the interfacial region. Increasing the substrate temperature is an effective means for reducing the interface defects and for improving the adhesion of the coatings. With the increase in the substrate thickness, the quantity of the vertical cracks in the coatings is reduced and their width becomes narrower.  相似文献   
59.
Thermomechanical performance of metallic alloys is directly related to the metal cleanliness that has always been a challenge for metallurgists. During liquid metal processing, particles can grow or decrease in size either by mass transfer with the liquid phase or by agglomeration/fragmentation mechanisms. As a function of numerical density of inclusions and of the hydrodynamics of the reactor, different numerical modeling approaches are proposed; in the case of an isolated particle, the Lagrangian technique coupled with a dissolution model is applied, whereas in the opposite case of large inclusion phase concentration, the population balance equation must be solved. Three examples of numerical modeling studies achieved at Institut Jean Lamour are discussed. They illustrate the application of the Lagrangian technique (for isolated exogenous inclusion in titanium bath) and the Eulerian technique without or with the aggregation process: for precipitation and growing of inclusions at the solidification front of a Maraging steel, and for endogenous inclusions in the molten steel bath of a gas-stirred ladle, respectively.  相似文献   
60.
Implants made of ceramics, and more particularly of calcium phosphates (hydroxyapatite: HA, mainly), promoting intimate contact with natural bone are nowadays merging. Addition of copper ions in bio-ceramics is expected to increase the biological compatibilities of bone graft substitutes. Previous works have shown that copper-doped hydroxyapatite (Cu-doped HA) ceramics can be prepared by solid-state sintering between HA and CuO powder mixtures at about 1100 °C; but, copper-substituted HA was found to be metastable leading to apatitic grains and Cu-rich grain boundaries during the sintering process. Ultra-rapid sintering is so needed. Selective laser sintering (SLS) is an additive manufacturing process that possesses the advantage to be based on ultra-fast sintering process under laser irradiation. SLS being used in literature for the application of laser on polymer-ceramic or poymer-metal composites the proper term all along the paper is Ceramic Powder Bed Laser Sintering (CPBLS). To achieve densification of Cu-doped HA ceramics from CPBLS process, one should control the composition/morphology/structure of the powder bed as well as three other important CPBLS parameters: (i) the applied energy from the laser beam, (ii) the laser power and the laser scanning speed, (iii) the distance between two successive lased lines. In this paper, the impact of all the main CPBLS parameters controlling the sintering of dip-coated Cu-doped HA layers on glass substrates is carefully investigated. Possibility of the creation of thin consolidated Cu-doped HA ceramic patterns, using the ultra-fast CPBLS process, is finally shown.  相似文献   
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