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Apolipoprotein E (apoE), an important determinant of plasma lipoprotein metabolism, has three common alleles (ε2, ε3, and ε4). Population studies have shown that the risk of diseases characterized by oxidative damage, such as coronary heart disease and Alzheimer’s disease, is significantly higher in ɛ4 carriers. We evaluated the association between apoE genotypes and plasma F2-isoprostane levels, an index of lipid peroxidation, in humans. Two hundred seventy-four healthy subjects (104 males, 170 females; 46.9±13.0 yr; 200 whites, 74 blacks; 81 nonsmokers, 64 passive smokers, and 129 active smokers) recruited for a randomized clinical antioxidant intervention trial were included in this analysis. ApoE genotype was determined by PCR and restriction enzyme digestion. Free plasma F2-isoprostane was measured by GC-MS. Genotype groups were compared using multiple regression analysis with adjustment for sex, age, race, smoking status, body mass index, plasma ascorbic acid, and β-carotene. Subjects with ε3/ε4 and ε4/ε4 genotype (ε4-carriers) and with ε2/ε3 and ε3/ε3 (non-ε4-carriers) were pooled for analysis. In subjects with high cholesterol levels (total cholesterol above 200 mg/dl), plasma F2-isoprostane levels were 29% higher in ε4 carriers than in non-ε4-carriers (P=0.0056). High-cholesterol subjects that are ε4 carriers have significantly higher levels of lipid peroxidation as assessed by circulating F2-isoprostane levels.  相似文献   
2.
The intramolecular palladium‐catalyzed reaction of N‐(iodoarylalkyl)pyrroles can be applied for the selective synthesis of medium‐sized rings by choosing the appropriate catalytic systems to direct the reaction to the alkene or to the pyrrole nucleus. These reactions can also be extended to the corresponding heteroaryl halides. Thus, reaction conditions have been established to access selectively to (hetero)fused indolizine, pyrroloazepine and pyrroloazocine systems.

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3.
The [(C2N2H9)VF(PO4)] compound has been synthesized by hydrothermal techniques under autogeneous pressure at 170°C. The compound was characterized from X-ray powder diffraction data with the Rietveld method. Its crystal structure consists of sheets linked by the ethylenediammonium cations and constructed by chains of VO3F2N octahedra. The thermal study indicates that the compound is stable up to 290°C. In the IR spectrum the bands of both the ethylenediammonium and phosphate ions are observed. From the reflectance diffuse spectrum the Dq and Racah parameters have been calculated. The magnetic measurements indicate the presence of antiferromagnetic interactions.  相似文献   
4.
The identification of acetic acid bacteria (AAB) from sound grapes from the Canary Islands is reported in the present study. No direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from Tenerife, La Palma and Lanzarote islands. Up to 396 AAB were isolated from those microvinifications and identified by 16S rRNA gene sequencing and phylogenetic analysis. With this method, Acetobacter pasteurianus, Acetobacter tropicalis, Gluconobacter japonicus and Gluconacetobacter saccharivorans were identified.However, no discrimination between the closely related species Acetobacter malorum and Acetobacter cerevisiae was possible. As previously described, 16S-23S rRNA gene internal transcribed spacer (ITS) region phylogenetic analysis was required to classify isolates as one of those species. These two species were the most frequently occurring, accounting for more than 60% of the isolates. For typing the AAB isolates, both the Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and (GTG)5-PCR techniques gave similar resolution. A total of 60 profiles were identified. Thirteen of these profiles were found in more than one vineyard, and only one profile was found on two different islands (Tenerife and La Palma).  相似文献   
5.
ABSTRACT

Steelmaking is immersed on continuous development of new steel products with higher performance and lower environmental footprint. This new paradigm places scrap recycling steel manufacturing processes as one of the main alternatives for the steelmaking industry. Using heterogeneous recycled scrap mixtures for building new and more demanding steel products require the use of Hot briquetted Iron (HBI) to reduce process uncertainties process. However, HBI might be stored for long periods of time and is affected by atmospheric corrosion that degrades its initial quality. The present work proposes, for the first time, a methodology to empirically quantify the influence of this degradation phenomenon on the EAF performance by extending the calculation of the Value In Use considerating degradation processes. The proposed equations allow estimating the extra cost induced by HBI degradation during storing periods and help calculating a more precise scrap mixture to deal with the required technical and cost specifications.  相似文献   
6.
Glial cells participate actively in the early cognitive decline in Alzheimer’s disease (AD) pathology. In fact, recent studies have found molecular and functional abnormalities in astrocytes and microglia in both animal models and brains of patients suffering from this pathology. In this regard, reactive gliosis intimately associated with amyloid plaques has become a pathological hallmark of AD. A recent study from our laboratory reports that astrocyte reactivity is caused by a direct interaction between amyloid beta (Aβ) oligomers and integrin β1. Here, we have generated four recombinant peptides including the extracellular domain of integrin β1, and evaluated their capacity both to bind in vitro to Aβ oligomers and to prevent in vivo Aβ oligomer-induced gliosis and endoplasmic reticulum stress. We have identified the minimal region of integrin β1 that binds to Aβ oligomers. This region is called signal peptide and corresponds to the first 20 amino acids of the integrin β1 N-terminal domain. This recombinant integrin β1 signal peptide prevented Aβ oligomer-induced ROS generation in primary astrocyte cultures. Furthermore, we carried out intrahippocampal injection in adult mice of recombinant integrin β1 signal peptide combined with or without Aβ oligomers and we evaluated by immunohistochemistry both astrogliosis and microgliosis as well as endoplasmic reticulum stress. The results show that recombinant integrin β1 signal peptide precluded both astrogliosis and microgliosis and endoplasmic reticulum stress mediated by Aβ oligomers in vivo. We have developed a molecular tool that blocks the activation of the molecular cascade that mediates gliosis via Aβ oligomer/integrin β1 signaling.  相似文献   
7.
Platelet-rich plasma (PRP) is a biologic therapy that promotes healing responses across multiple medical fields, including the central nervous system (CNS). The efficacy of this therapy depends on several factors such as the donor’s health status and age. This work aims to prove the effect of PRP on cellular models of the CNS, considering the differences between PRP from young and elderly donors. Two different PRP pools were prepared from donors 65–85 and 20–25 years old. The cellular and molecular composition of both PRPs were analyzed. Subsequently, the cellular response was evaluated in CNS in vitro models, studying proliferation, neurogenesis, synaptogenesis, and inflammation. While no differences in the cellular composition of PRPs were found, the molecular composition of the Young PRP showed lower levels of inflammatory molecules such as CCL-11, as well as the presence of other factors not found in Aged PRP (GDF-11). Although both PRPs had effects in terms of reducing neural progenitor cell apoptosis, stabilizing neuronal synapses, and decreasing inflammation in the microglia, the effect of the Young PRP was more pronounced. In conclusion, the molecular composition of the PRP, conditioned by the age of the donors, affects the magnitude of the biological response.  相似文献   
8.
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder and the most common cause of dementia in aging populations. Recently, the regulation of neurolipid-mediated signaling and cerebral lipid species was shown in AD patients. The triple transgenic mouse model (3xTg-AD), harboring βAPPSwe, PS1M146V, and tauP301L transgenes, mimics many critical aspects of AD neuropathology and progressively develops neuropathological markers. Thus, in the present study, 3xTg-AD mice have been used to test the involvement of the neurolipid-based signaling by endocannabinoids (eCB), lysophosphatidic acid (LPA), and sphingosine 1-phosphate (S1P) in relation to the lipid deregulation. [35S]GTPγS autoradiography was used in the presence of specific agonists WIN55,212-2, LPA and CYM5442, to measure the activity mediated by CB1, LPA1, and S1P1 Gi/0 coupled receptors, respectively. Consecutive slides were used to analyze the relative intensities of multiple lipid species by MALDI Mass spectrometry imaging (MSI) with microscopic anatomical resolution. The quantitative analysis of the astrocyte population was performed by immunohistochemistry. CB1 receptor activity was decreased in the amygdala and motor cortex of 3xTg-AD mice, but LPA1 activity was increased in the corpus callosum, motor cortex, hippocampal CA1 area, and striatum. Conversely, S1P1 activity was reduced in hippocampal areas. Moreover, the observed modifications on PC, PA, SM, and PI intensities in different brain areas depend on their fatty acid composition, including decrease of polyunsaturated fatty acid (PUFA) phospholipids and increase of species containing saturated fatty acids (SFA). The regulation of some lipid species in specific brain regions together with the modulation of the eCB, LPA, and S1P signaling in 3xTg-AD mice indicate a neuroprotective adaptation to improve neurotransmission, relieve the myelination dysfunction, and to attenuate astrocyte-mediated neuroinflammation. These results could contribute to identify new therapeutic strategies based on the regulation of the lipid signaling in familial AD patients.  相似文献   
9.
Thermal diffusivity of nonflat plates using the flash method   总被引:1,自引:0,他引:1  
The flash method is the standard technique to measure the thermal diffusivity of solid samples. It consists of heating the front surface of an opaque sample by a brief light pulse and detecting the temperature evolution at its rear surface. The thermal diffusivity is obtained by measuring the time corresponding to the half maximum of the temperature rise, which only depends on the sample thickness and thermal diffusivity through a simple formula. Up to now, the flash method has been restricted to flat samples. In this work, we extend the flash method to measure the thermal diffusivity of nonflat samples. In particular, we focus on plates with cylindrical and spherical shapes. The theoretical model indicates that the same expression for flat samples can also be applied to cylindrical and spherical plates, except for extremely curved samples. Accordingly, a curvature limit for the application of the expression for flat samples is established. Flash measurements on lead foils of cylindrical shape confirm the validity of the model.  相似文献   
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