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111.
Decreased Catalase Activity but Unchanged Superoxide Dismutase Activity in Brains of Patients with Dementia of Alzheimer Type 总被引:5,自引:1,他引:4
Wieland Gsell Rudolf Conrad Majida Hickethier Emin Sofic Lutz Frölich Ildiko Wichart Kurt Jellinger Gunther Moll †Gerhard Ransmayr Helmut Beckmann Peter Riederer 《Journal of neurochemistry》1995,64(3):1216-1223
Abstract: "Oxidative stress" may be of significance in the etiopathogenesis of dementia of Alzheimer type (DAT). Therefore, we measured activities of the enzymes superoxide dismutase (SOD) and catalase (CAT), which detoxicate reactive oxygen species. Enzyme activities were measured postmortem in basal ganglia, cortical, and limbic brain regions of patients with DAT and age-matched controls. SOD activity increased with age in basal nucleus of Meynert. However, there was no significant difference in SOD activity between DAT and controls. CAT activity was independent of age and postmortem time. There were significant reductions in CAT activity in parietotemporal cortex, basal ganglia, and amygdala in DAT compared with controls ( p < 0.05 to 0.01). Our findings are in line with the assumption that reactive oxygen species could contribute to the pathogenesis of DAT. Absence of these changes in basal nucleus of Meynert might reflect retrograde degeneration of cholinergic fibers. 相似文献
112.
113.
Biological Trace Element Research - The original version of this article contained mistakes: the units mg/kg-1 and μg/kg-1 found on tables 1, 2, 4, 5 and 6 should be mg kg−1 and μg... 相似文献
114.
How plot shape and spatial arrangement affect plant species richness counts: implications for sampling design and rarefaction analyses
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115.
Some evolutionary explanations of cross-cultural differences propose that human personality is caused by pathogen stress.
Both xenophobia and ethnocentrism evolved under conditions with high parasite prevalence. Further, inter-individual variation
in disgust or fear of parasites is expected to be influenced by human health, where healthy people should express lower disgust
sensitivity to parasites. We examined inter-individual variation of children’s fear, disgust and self-perceived danger between
two distinct cultures differing in overall pathogen prevalence. We found that children were able to distinguish between disease-relevant
and disease-irrelevant groups of invertebrates and that children in regions with high pathogen prevalence expressed greater
fear, disgust and self-perceived danger of all animals, irrespective of disease threat. After controlling for confounding
factors, better health of children was associated with lower perceived danger of disease-relevant animals. Gender differences
were found only in conditions with low pathogen stress. Our results support the idea that cross-cultural differences in human
perception of animals are mediated by pathogen threat. Further research is necessary to investigate causal relationship between
human health and avoidance of potentially hazardous animals. 相似文献
116.
Ziver T Yuksel P Ipek G Yekeler I Bayramoglu Z Tireli E Saribas S Aslan M Yalvac SD Ozdomanic I Torlak Z Dirican A Torun MM Kocazeybek B 《The new microbiologica》2010,33(3):233-242
Helicobacter pylori is thought to be related to atherosclerosis and aneurysm development. We aimed to detect virulance factors of H. pylori and examine the potential etiopathogenetic relationship between aortic aneurysm and H. pylori, 58 abdominal aortic aneurysm (AAA) and 38 ascending aortic aneurysm (AsAA) cases and 57 Healty control group (HCG) were included. We investigated H. pylori IgG by ELISA and virulance factors by Western-Blot (WB) method. No difference was found between AAA (67.24%), AsAA (73.68%) and HCG (57.89%) for H. pylori IgG (p > 0.05). A significant difference was found between AsAA (78.95%) and HCG (57.89%) for H.pylori IgG (p < 0.05) by ELISA and a significant difference was found only between AsAA (100%) and HCG (37.5%) for H. pylori IgG in the 45-55 age group by WB. A statistically significant difference was found between AAA and AsAA for VacA and CagA + VacA and CagA + VacA + UreA antigens and also a significant difference was found between AsAA and HCG for CagA + UreA antigens (p < 0.05). Finally, we suggest that H. pylori VacA has a more important role than CagA in the development of two aneurysms especially in ruptured AAA. New extended studies detecting H. pylori DNA are needed to detect the aetiopathogenesis between aneurysm types and H. pylori. 相似文献
117.
The karyotype and major ribosomal sites as revealed using silver staining of Anatolian leuciscine cyprinid fish Acanthobrama marmid were studied. The diploid chromosome number was invariably 2n = 50. Karyotype consisted of eight pairs of metacentric, 13 pairs of submetacentric and four pairs of subtelocentric to acrocentric
chromosomes. The largest chromosome pair of the complement was subtelo-to acrocentric characteristically, which is a characteristic
cytotaxonomic marker for representatives of the cyprinid lineage Leuciscinae. The nucleolar organizer regions (NORs) were
detected in the telomeres of two pairs of medium sized submeta-to subtelocentric chromosomes. No heteromorphic sex chromosomes
were found. The karyotype pattern of A. marmid is nearly identical to that found in most other representatives of the Eurasian leuciscine cyprinids, while the multiple
NOR phenotype appears to be more derived as opposed to a uniform one, ubiquitous in this group. 相似文献
118.
Sacrificial bonds and hidden length: unraveling molecular mesostructures in tough materials
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Fantner GE Oroudjev E Schitter G Golde LS Thurner P Finch MM Turner P Gutsmann T Morse DE Hansma H Hansma PK 《Biophysical journal》2006,90(4):1411-1418
Sacrificial bonds and hidden length in structural molecules and composites have been found to greatly increase the fracture toughness of biomaterials by providing a reversible, molecular-scale energy-dissipation mechanism. This mechanism relies on the energy, of order 100 eV, needed to reduce entropy and increase enthalpy as molecular segments are stretched after being released by the breaking of weak bonds, called sacrificial bonds. This energy is relatively large compared to the energy needed to break the polymer backbone, of order a few eV. In many biological cases, the breaking of sacrificial bonds has been found to be reversible, thereby additionally providing a "self-healing" property to the material. Due to the nanoscopic nature of this mechanism, single molecule force spectroscopy using an atomic force microscope has been a useful tool to investigate this mechanism. Especially when investigating natural molecular constructs, force versus distance curves quickly become very complicated. In this work we propose various types of sacrificial bonds, their combination, and how they appear in single molecule force spectroscopy measurements. We find that by close analysis of the force spectroscopy curves, additional information can be obtained about the molecules and their bonds to the native constructs. 相似文献
119.
Cytokine signaling plays an important role in the survival and differentiation of vertebrate hematopoietic cells. In red blood cells, erythropoietin is a key component of the differentiation program and maintains the homeostasis of the erythroid compartment. In the adult, anemia stimulates high levels of circulating erythropoietin that drives erythropoiesis to restore normal levels of red blood cells in circulation. Erythropoietin activates the erythropoietin receptor on immature red blood cell precursors to promote their survival and differentiation. Although extensively studied in mammalian systems, a complete understanding of the function of the erythropoietin receptor during primitive erythropoiesis has been lacking. To address this problem, we have cloned the Xenopus laevis erythropoietin receptor in order to further understand the development of primitive erythropoiesis. The amphibian erythropoietin receptor shares 33% amino acid sequence identity with the mammalian erythropoietin receptors and contains the conserved extracellular ligand binding and fibronectin domains, the WSXWS motif common to cytokine receptors, and several tyrosine phosphorylation sites located on the intracellular domain of the receptor. Expression of the erythropoietin receptor is first detected by in situ hybridization in the ventral blood island during tailbud stages. 相似文献
120.
Ramazan Kalin Zeynep Koksal Pinar Kalin Muhammet Karaman lhami Gulcin Hasan Ozdemir 《Journal of biochemical and molecular toxicology》2020,34(1)
Lactoperoxidase (LPO), an antioxidant enzyme, is a natural antimicrobial system that eliminates the harmful effects of microorganisms in milk. It has a wide range of applications and is also preferred in cosmetic and clinical applications, as well as used in foods. The use of antioxidants is well recognized in the food and feed industries to improve the shelf life of products. This study aimed to determine the in vitro inhibition effects of Trolox, α‐tocopherol, butylated hydroxyanisole, butylated hydroxytoluene, and propyl gallate, which are commonly used as antioxidants in food and pharmaceutical products. For this purpose, LPO was first purified in a single step using sepharose‐4B‐l ‐tyrosine‐sulfanilamide affinity gel chromatography. Also, some inhibition parameters, including half‐maximal inhibitory concentration (IC50), Ki values, and inhibition types, were calculated for each antioxidant molecule. The IC50 values of these molecules, which exhibited competitive inhibition, varied between 377.7 and 3397.8 nM. Molecular docking studies were also performed for all compounds. According to the binding scores, α‐tocopherol was shown to exhibit the most effective inhibitor property (IC50: 377.7 nM and Ki: 635.8 ± 16.8 nM) among the standard antioxidants used in this study. Inhibiting the LPO activity by standard antioxidants results in the weakening of the immune system during lactation, which is important for metabolism. 相似文献