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881.
Abigail Lopes Thais Ceresér Vilela Luciane Taschetto Franciele Vuolo Fabricia Petronilho Felipe Dal-Pizzol Emilio Luiz Streck Gustavo Costa Ferreira Patrícia Fernanda Schuck 《Molecular neurobiology》2014,50(3):1124-1130
Hereditary fructose intolerance is an autosomal recessive disorder characterized by the accumulation of fructose in tissues and biological fluids of patients. The disease results from a deficiency of aldolase B, responsible for metabolizing fructose in the liver, kidney, and small intestine. We investigated the effect of acute fructose administration on oxidative stress and neuroinflammatory parameters in the cerebral cortex of 30-day-old Wistar rats. Animals received subcutaneous injection of sodium chloride (0.9 %) (control group) or fructose solution (5 μmol/g) (fructose group). One hour later, the animals were euthanized and the cerebral cortex was isolated. Oxidative stress (levels of thiobarbituric acid-reactive substances (TBA-RS), carbonyl content, nitrate and nitrite levels, 2′,7′-dihydrodichlorofluorescein (DCFH) oxidation, glutathione (GSH) levels, as well as the activities of catalase (CAT) and superoxide dismutase (SOD)) and neuroinflammatory parameters (TNF-α, IL-1β, and IL-6 levels and myeloperoxidase (MPO) activity) were investigated. Acute fructose administration increased levels of TBA-RS and carbonyl content, indicating lipid peroxidation and protein damage. Furthermore, SOD activity increased, whereas CAT activity was decreased. The levels of GSH, nitrate, and nitrite and DCFH oxidation were not altered by acute fructose administration. Finally, cytokines IL-1β, IL-6, and TNF-α levels, as well as MPO activity, were not altered. Our present data indicate that fructose provokes oxidative stress in the cerebral cortex, which induces oxidation of lipids and proteins and changes of CAT and SOD activities. It seems therefore reasonable to propose that antioxidants may serve as an adjuvant therapy to diets or to other pharmacological agents used for these patients, to avoid oxidative damage to the brain. 相似文献
882.
Umaima Al-Alem Garth Rauscher Ebony Shah Ken Batai Abeer Mahmoud Erin Beisner Abigail Silva Caryn Peterson Rick Kittles 《PloS one》2014,9(11)
Introduction
Non-Hispanic (nH) Black and Hispanic women are disproportionately affected by early onset disease, later stage, and with more aggressive, higher grade and ER/PR negative breast cancers. The purpose of this analysis was to examine whether genetic ancestry could account for these variation in breast cancer characteristics, once data were stratified by self-reported race/ethnicity and adjusted for potential confounding by social and behavioral factors.Methods
We used a panel of 100 ancestry informative markers (AIMs) to estimate individual genetic ancestry in 656 women from the “Breast Cancer Care in Chicago” study, a multi-ethnic cohort of breast cancer patients to examine the association between individual genetic ancestry and breast cancer characteristics. In addition we examined the association of individual AIMs and breast cancer to identify genes/regions that may potentially play a role in breast cancer disease disparities.Results
As expected, nH Black and Hispanic patients were more likely than nH White patients to be diagnosed at later stages, with higher grade, and with ER/PR negative tumors. Higher European genetic ancestry was protective against later stage at diagnosis (OR 0.7 95%CI: 0.54–0.92) among Hispanic patients, and higher grade (OR 0.73, 95%CI: 0.56–0.95) among nH Black patients. After adjustment for multiple social and behavioral risk factors, the association with later stage remained, while the association with grade was not significant. We also found that the AIM SNP rs10954631 on chromosome 7 was associated with later stage (p = 0.02) and higher grade (p = 0.012) in nH Whites and later stage (p = 0.03) in nH Blacks.Conclusion
Non-European genetic ancestry was associated with later stage at diagnosis in ethnic minorities. The relation between genetic ancestry and stage at diagnosis may be due to genetic factors and/or unmeasured environmental factors that are overrepresented within certain racial/ethnic groups. 相似文献883.
Jennifer M. Fettweis Myrna G. Serrano Bernice Huang J. Paul Brooks Abigail L. Glascock Nihar U. Sheth Vaginal Microbiome Consortium Jerome F. Strauss III Kimberly K. Jefferson Gregory A. Buck 《PloS one》2014,9(10)
Humans are colonized by thousands of bacterial species, but it is difficult to assess the metabolic and pathogenic potential of the majority of these because they have yet to be cultured. Here, we characterize an uncultivated vaginal mycoplasma tightly associated with trichomoniasis that was previously known by its 16S rRNA sequence as “Mnola.” In this study, the mycoplasma was found almost exclusively in women infected with the sexually transmitted pathogen Trichomonas vaginalis, but rarely observed in women with no diagnosed disease. The genomes of four strains of this species were reconstructed using metagenome sequencing and assembly of DNA from four discrete mid-vaginal samples, one of which was obtained from a pregnant woman with trichomoniasis who delivered prematurely. These bacteria harbor several putative virulence factors and display unique metabolic strategies. Genes encoding proteins with high similarity to potential virulence factors include two collagenases, a hemolysin, an O-sialoglycoprotein endopeptidase and a feoB-type ferrous iron transport system. We propose the name “Candidatus Mycoplasma girerdii” for this potential new pathogen. 相似文献
884.
Natallia Shved Cordula Haas Christina Papageorgopoulou Guelfirde Akguel Katja Paulsen Abigail Bouwman Christina Warinner Frank Rühli 《PloS one》2014,9(10)
Mummified human tissues are of great interest in forensics and biomolecular archaeology. The aim of this study was to analyse post mortem DNA alterations in soft tissues in order to improve our knowledge of the patterns of DNA degradation that occur during salt mummification. In this study, the lower limb of a female human donor was amputated within 24 h post mortem and mummified using a process designed to simulate the salt dehydration phase of natural or artificial mummification. Skin and skeletal muscle were sampled at multiple time points over a period of 322 days and subjected to genetic analysis. Patterns of genomic fragmentation, miscoding lesions, and overall DNA degradation in both nuclear and mitochondrial DNA was assessed by different methods: gel electrophoresis, multiplex comparative autosomal STR length amplification, cloning and sequence analysis, and PCR amplification of different fragment sizes using a damage sensitive recombinant polymerase. The study outcome reveals a very good level of DNA preservation in salt mummified tissues over the course of the experiment, with an overall slower rate of DNA fragmentation in skin compared to muscle. 相似文献
885.
Unai Aresti Sergio Carrera Eluska Iruarrizaga Natalia Fuente Ines Marrodan Abigail Ruiz de Lobera Alberto Mu?oz Aitziber Buque Elizabeth Condori Irene Ugalde Bego?a Calvo Guillermo López Vivanco 《PloS one》2014,9(10)
The biological roles of estrogen receptor 1 (ERS1), estrogen receptor 2 (ERS2), and aromatase (CYP19A1) genes in the development of non-small cell lung cancer (NSCLC) is unclear, as is the use of their expression as a prognostic factor. The aim of this study was to investigate the prognostic value of estrogen receptors and aromatase mRNA expression, along with aromatase protein concentration, in resected NSCLC patients. Tumor and non-tumor lung tissue samples were analyzed for the mRNA expression of ERS1, ERS2 and CYP19A1 by RT-PCR. Aromatase concentration was measured with an ELISA. A total of 96 patients were included. ERS1 expression was significantly higher in non-tumor tissue than in tumor samples. Two gene expression categories were created for each gene (and protein): high and low. ERS1 high category showed increased overall survival (OS) when compared to the low expression category. Aromatase protein concentration was significantly higher in tumor samples. Higher ERS1 expression in tumor tissues was related to longer overall survival. The analysis of gene expression combinations provides evidence for longer OS when both ERS1 and ERS2 are highly expressed. ESR1, alone or in combination with ERS2 or CYP19A1, is the most determining prognostic factor within the analyzed 3 genes. It seems that ERS1 can play a role in NSCLC prognosis, alone or in combination with other genes such as ERS2 or Cyp19a1. ERS2 in combination with aromatase concentration could have a similar function. 相似文献
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