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31.
Parinaric acid (PnA) is a fluorescent polyunsaturated fatty acid which can be used as a probe to study lipid peroxidation processes. The basic methodology is simple and sensitive, and offers a direct ‘view’ of the oxidative decay of a fatty acid and the effects of prooxidant and antioxidant factors. A distinctive feature of the PnA assay is that it does not measure a lipid peroxidation end product, but monitors lipid oxidative stress in its initial stages. This review highlights the methodological characteristics of the PnA assay, and describes the various applications in which PnA and PnA derivatives have yielded useful information. These applications range from oxidant and antioxidant studies in lipid model systems to comparative studies of oxidation processes in normal and pathological red blood cells, and also include studies of lipoprotein oxidation. 相似文献
32.
Anne-Sophie Carlo 《朊病毒》2013,7(5):378-382
In the brain, apolipoprotein E (APOE) delivers cholesterol-rich lipoproteins to neurons to support synaptogenesis and maintenance of synaptic connections. Three APOE alleles exist in the human population with ε4 being an Alzheimer disease (AD) risk gene and ε2 being protective relative to the common ε3 variant. Many hypotheses have been advanced concerning allele-specific effects of APOE on neurodegeneration including effects on Aβ clearance, synaptic transmission, or neurotoxicity. Central to most proposed APOE functions is its interaction with receptors that mediate cellular uptake of this ligand. Several members of the LDL receptor gene family have been implicated as APOE receptors in the (patho)physiology of APOE in the brain, yet their specific modes of action in AD remain controversial. Recently, the pro-neurotrophin receptor sortilin has been identified as a novel APOE receptor in neurons. Ablation of sortilin expression in mice results in accumulation of APOE and Aβ in the brain. Moreover, primary neurons lacking sortilin exhibit significantly impaired uptake of APOE/Aβ complexes. Despite increased brain APOE levels, sortilin-deficient animals recapitulate anomalies in brain lipid homeostasis seen in APOE null mice, indicating functional deficiency in APOE uptake pathways. Taken together, these findings suggest a link between Aβ catabolism and pro-neurotrophin signaling converging on this receptor pathway. 相似文献
33.
《African Journal of Aquatic Science》2013,38(1):84-88
The fish population of the lower reaches of the Sanyati River was studied using multifilament gillnets and monthly sampling was conducted over 13 consecutive months. A total of 15 fish species belonging to seven families were collected and variations in monthly catches and catch per unit effort and condition were observed. The five most common species exhibited a seasonal breeding pattern, with most breeding occurring in the rainy season. The exotic Nile tilapia Oreochromis niloticus was found to have established itself in the Sanyati River. The results of this study were compared with those of previous workers on Lake Kariba. 相似文献
34.
DNA damage created by endogenous or exogenous genotoxic agents can exist in multiple forms, and if allowed to persist, can promote genome instability and directly lead to various human diseases, particularly cancer, neurological abnormalities, immunodeficiency and premature aging. To avoid such deleterious outcomes, cells have evolved an array of DNA repair pathways, which carry out what is typically a multiple-step process to resolve specific DNA lesions and maintain genome integrity. To fully appreciate the biological contributions of the different DNA repair systems, one must keep in mind the cellular context within which they operate. For example, the human body is composed of non-dividing and dividing cell types, including, in the brain, neurons and glial cells. We describe herein the molecular mechanisms of the different DNA repair pathways, and review their roles in non-dividing and dividing cells, with an eye toward how these pathways may regulate the development of neurological disease. 相似文献
35.
36.
Alexis Rodriguez Marie Ø. Pedersen Elba Villegas Bruno Rivas-Santiago Jessica Villegas-Moreno Carlos Amero Raymond S. Norton Gerardo Corzo 《Proteins》2020,88(1):175-186
The spread of multidrug resistant bacteria owing to the intensive use of antibiotics is challenging current antibiotic therapies, and making the discovery and evaluation of new antimicrobial agents a high priority. The evaluation of novel peptide sequences of predicted antimicrobial peptides from different sources is valuable approach to identify alternative antibiotic leads. Two strategies were pursued in this study to evaluate novel antimicrobial peptides from the human β-defensin family (hBD). In the first, a 32-residue peptide was designed based on the alignment of all available hBD primary structures, while in the second a putative 35-residue peptide, hBD10, was mined from the gene DEFB110. Both hBDconsensus and hBD10 were chemically synthesized, folded and purified. They showed antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Mycobacterium tuberculosis, but were not hemolytic on human red blood cells. The NMR-based solution structure of hBDconsensus revealed that it adopts a classical β-defensin fold and disulfide connectivities. Even though the mass spectrum of hBD10 confirmed the formation of three disulfide bonds, it showed limited dispersion in 1H NMR spectra and structural studies were not pursued. The evaluation of different β-defensin structures may identify new antimicrobial agents effective against multidrug-resistant bacterial strains. 相似文献
37.
Tristan Richard Yorgos PapastamoulisPierre Waffo-Teguo Jean-Pierre Monti 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Alzheimer's disease (AD) is a progressive neurodegenerative disorder. There is a consensus that Aβ is a pathologic agent and that its toxic effects, which are at present incompletely understood, may occur through several potential mechanisms. Polyphenols are known to have wide-ranging properties with regard to health and for helping to prevent various diseases like neurodegenerative disorders. Thus inhibiting the formation of toxic Aβ assemblies is a reasonable hypothesis to prevent and perhaps treat ADMethods
Solution NMR and molecular modeling were used to obtain more information about the interaction between the Aβ1–40 and the polyphenol ε-viniferin glucoside (EVG) and particularly the Aβ residues involved in the complex.Results
The study demonstrates the formation of a complex between two EVG molecules and Aβ1–40 in peptide characteristic regions that could be in agreement with the inhibition of aggregation. Indeed, in previous studies, we reported that EVG strongly inhibited in vitro the fibril formation of the full length peptides Aβ1–40 and Aβ1–42, and had a strong protective effect against PC12 cell death induced by these peptides.Conclusion
For the full length peptide Aβ1–40, the binding sites observed could explain the EVG inhibitory effect on fibrillization and thus prevent amyloidogenic neurotoxicity.General significance
Even though this interaction might be important at the biological level to explain the protective effect of polyphenols in neurodegenerative diseases, caution is required when extrapolating this in vitro model to human physiology. 相似文献38.
Paul Faustin Seke Etet Lorella Vecchio Patrice Bogne Kamga Elias Nchiwan Nukenine Mauro Krampera Armel Hervé Nwabo Kamdje 《生物化学与生物物理学报:癌评论》2013
Wnts are a family of evolutionary-conserved secreted signaling molecules critically involved in a variety of developmental processes and in cell fate determination. A growing body of evidence suggests that Wnt signaling plays a crucial role in the influence of bone marrow stromal microenvironment on the balance between hematopoietic stem cell self-renewal and differentiation. Emerging clinical and experimental evidence also indicates Wnt signaling involvement in the disruption of the latter balance in hematologic malignancies, where the stromal microenvironment favors the homing of cancer cells to the bone marrow, as well as leukemia stem cell development and chemoresistance. In the present review, we summarize and discuss the role of the canonical Wnt signaling pathway in normal hematopoiesis and hematologic malignancies, with regard to recent findings on the stromal microenvironment involvement in these process and diseases. 相似文献
39.
《Journal of bryology》2013,35(4):265-274
AbstractThe distribution of Bazzania trilobata in Poland coincides with two parts of the natural distribution range of Norway spruce: the mountains of southern Poland and the northeastern lowlands. The occurrence of this species is connected with primeval forest communities and it was recognized as a relict of them. Genetic variation of 10 populations of B. trilobata from two different regions of Poland (lowlands and mountains) was studied in order to establish the genetic structure of this species and to compare the level of genetic variation within and among populations originating from primeval and managed forests. An analysis based on polymorphic inter-simple sequence repeat (ISSR) loci revealed a high level of total gene diversity in B. trilobata (H T=0.308). A higher amount of polymorphism was found among than within populations. Genetic variation of populations from the primary forest (Tatras and Bia?owieza National Park) was higher than for those originating from disturbed habitats. The Bayesian method showed consistent grouping of samples corresponding with populations, with the best grouping in 12 different clusters reflecting a geographic pattern. The geographic pattern of genetic differentiation was supported by a neighbour-joining (NJ) dendrogram based on genetic distances. All mountain populations were grouped together in one subcluster, but lowland populations were more differentiated and did not form one clear group. 相似文献
40.
Luz Ma. González-Huerta Olga Messina-Baas Héctor Urueta Jaime Toral-López Sergio A. Cuevas-Covarrubias 《Gene》2013