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1.
Anandamide, an endogenous ligand for central cannabinoid receptors, is released from neurons on depolarization and rapidly inactivated. Anandamide inactivation is not completely understood, but it may occur by transport into cells or by enzymatic hydrolysis. The compound N-(4-hydroxyphenyl)arachidonylamide (AM404) was shown to inhibit high-affinity anandamide accumulation in rat neurons and astrocytes in vitro, an indication that this accumulation resulted from carrier-mediated transport. Although AM404 did not activate cannabinoid receptors or inhibit anandamide hydrolysis, it enhanced receptor-mediated anandamide responses in vitro and in vivo. The data indicate that carrier-mediated transport may be essential for termination of the biological effects of anandamide, and may represent a potential drug target.  相似文献   
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In absence of thrombocytosis, periodic bloodlettings represent the elective therapy of polycythemia vera. In the present study we tested if neocytoapheresis, a method able to remove large quantities of younger, and then bigger red cells could represent an alternative therapeutic choice in these patients. We found that the employment of neocytoapheresis produced a remarkable delay in the time of procedures with a mean interval of 100 +/- 55 days. The mean value of hematocrit before neocytopheresis is resulted statistically different in comparison with the hematocrit after the procedure (p = 0.0001). The reticulocyte count is resulted higher in apheresis product in comparison with the blood control measured before procedure (p = 0.0001). In the same way, the mean corpuscular volume in the collection bags was higher than the volume measured before neocytoapheresis (p = 0.0095). We did not find any variation about the mean values of white blood cells and platelets before and after neocytoapheresis in the patients examined. These preliminary data seem to underline a better withdrawal of big size cells by this technique suggesting the efficacy of neocytoapheresis in the treatment of polycythemia vera.  相似文献   
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Insulin-like growth factor II (IGF-II) plays a key role in mammalian growth, influencing foetal cell division and differentiation and possibly metabolic regulation. The mature 67 amino acid peptide shares sequence homology with both insulin and IGF-I. The liver is the main endocrine source of IGFs, but autocrine/paracrine activity is found in most tissues. The type 1 receptor mediates most of the biological effects of IGF-I and IGF-II; the type 2 receptor is involved with IGF-II degradation. Binding proteins may both localise IGFs to the receptors and regulate their activities. The IGF2 gene is maternally imprinted in mouse and human. Relaxation of IGF2 imprinting occurs in the Beckwith-Wiedemann syndrome of somatic overgrowth, sporadic Wilms' tumour and a number of other cancers. In the general adult population, the IGF2-INS gene cluster may also influence body weight, in which case IGF-II function could become a target for therapeutic intervention in obesity.  相似文献   
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The lockdown due to COVID-19 in Italy resulted in the sudden closure of schools, with a shift from traditional teaching to the online one. Through an online questionnaire, this survey explores teachers' experience of online teaching, the level of risk factors (e.g., stress) and protective factors (e.g., locus of control) and their impact on satisfaction levels during the social distancing. One hundred seven high school teachers from Lombardy, an Italian region very affected by the COVID-19 outbreak, participated. Results show that depression and stress are the main predictors of satisfaction levels for online teaching. In addition, coping, locus of control and self-efficacy emerge as important protective factors. Finally, although there is great satisfaction with the online teaching experience, critical elements emerged. This study is relevant because it describes the critical elements of the online teaching experience, and identifies some protective factors and the main risk factors in teachers operating in an area strongly marked by social restrictions imposed by the pandemic. High school teachers emerge as a sub-group of the general population with specific psychological reactions. Considering the results, it is possible to suggest providing high-quality educational support and crisis-psychological oriented services to teachers, and help to maintain the psychological well-being.  相似文献   
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Circular RNAs (circRNAs) are a large class of RNAs with regulatory functions within cells. We recently showed that circSMARCA5 is a tumor suppressor in glioblastoma multiforme (GBM) and acts as a decoy for Serine and Arginine Rich Splicing Factor 1 (SRSF1) through six predicted binding sites (BSs). Here we characterized RNA motifs functionally involved in the interaction between circSMARCA5 and SRSF1. Three different circSMARCA5 molecules (Mut1, Mut2, Mut3), each mutated in two predicted SRSF1 BSs at once, were obtained through PCR-based replacement of wild-type (WT) BS sequences and cloned in three independent pcDNA3 vectors. Mut1 significantly decreased its capability to interact with SRSF1 as compared to WT, based on the RNA immunoprecipitation assay. In silico analysis through the “Find Individual Motif Occurrences” (FIMO) algorithm showed GAUGAA as an experimentally validated SRSF1 binding motif significantly overrepresented within both predicted SRSF1 BSs mutated in Mut1 (q-value = 0.0011). U87MG and CAS-1, transfected with Mut1, significantly increased their migration with respect to controls transfected with WT, as revealed by the cell exclusion zone assay. Immortalized human brain microvascular endothelial cells (IM-HBMEC) exposed to conditioned medium (CM) harvested from U87MG and CAS-1 transfected with Mut1 significantly sprouted more than those treated with CM harvested from U87MG and CAS-1 transfected with WT, as shown by the tube formation assay. qRT-PCR showed that the intracellular pro- to anti-angiogenic Vascular Endothelial Growth Factor A (VEGFA) mRNA isoform ratio and the amount of total VEGFA mRNA secreted in CM significantly increased in Mut1-transfected CAS-1 as compared to controls transfected with WT. Our data suggest that GAUGAA is the RNA motif responsible for the interaction between circSMARCA5 and SRSF1 as well as for the circSMARCA5-mediated control of GBM cell migration and angiogenic potential.  相似文献   
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Two of the majorNuphar alkaloids, nupharolutine and 6,6-dihydroxythiobinupharidine, were isolated from the aquatic perennial herbNuphar lutea (L.) Sibth. & Sm., yellow water lily. In a lettuce seedling bioassay of the two pure compounds, the former was inactive and the latter was highly inhibitory of radicle elongation at concentrations greater than 2 ppm. Structures and stereochemistry of the two compounds were confirmed by DEPT,1H-1H COSY,1H-13C COSY, and1H-1H NOESY experiments.  相似文献   
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We have synthesized a series of fully aliphatic polyimides (APIs) from bicyclo[2,2,2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic dianhydride (BOCA) and various aliphatic diamines, including linear aliphatic, flexible alicyclic, and rigid adamantyl diamines. We performed the polymerization reactions using one‐step syntheses in m‐cresol at elevated temperatures without the isolation of poly(amic) acid. The chemical composition and structure of the polymers were characterized by nuclear magnetic resonance (NMR) and infrared (IR) spectrometry. The characterization data are reported from analyses using gel permeation chromatography (GPC), thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and wide‐angle X‐ray diffraction (WXAD) measurements. The polyimides are also subjected to solubility, solution viscosity, tensile strength, transparency, and dielectric constant measurements. The resultant polyimides possess well‐controlled molecular weight, reasonable intrinsic viscosity, good transparency, enhanced solubility, low dielectric constants, and high glass transition temperature, together with marginal thermal and mechanical stability. These properties were enhanced in copolyimides containing equimolar amounts of rigid and flexible moieties. These rigid‐rod APIs derived from the alicyclic dianhydride and aliphatic diamines are promising candidates as advanced materials for future applications in micro‐ and photoelectronic devices. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3316–3326, 2006  相似文献   
10.
In this study, recycled polyethylene (rPE) based microfibrillated composites (MFCs) were developed while incorporating recycled poly(ethylene terephthalate) (rPET) and recycled polyamide 6 (rPA) as the reinforcing fibrillar phases at a given weight ratio of 80 wt% (rPE)/20 wt% (rPET or rPA). The blends were first melt processed using a twin-screw extruder. The extrudates were then cold stretched at a drawing ratio of 2.5 to form rPET and rPA fibrillar structures. Next, the pelletized drawn samples were injection molded at the barrel temperatures below the melting temperatures of rPET and rPA. The tensile, three-point bending, impact strength, dynamic thermomechanical, and rheological properties of the fabricated MFCs were analyzed. The effects of injection molding barrel temperature (i.e., 150°C and 190°C) and extrusion melt processing temperature (i.e., 250°C and 275°C) on the generated fibrillar structure and the resultant properties were explored. A strong correlation between the fibrillar morphology and the mechanical properties with the extrusion and injection molding temperatures was observed. Moreover, the ethylene/n-butyl acrylate/glycidyl methacrylate (EnBAGMA) terpolymer and maleic anhydride grafted PE (MAH-g-PE) were, respectively, melt processed with rPE/rPET and rPE/rPA6 blends as compatibilizers. The compatibilizers refined the fibrillar structure and remarkably influenced mechanical properties, specifically the impact strength.  相似文献   
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