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Background: Alzheimer's disease (AD) is characterized by progressive memory loss and cognitive impairment. The aggregation of amyloid β (Aβ) and hyperphosphorylated tau protein are two major pathological features of AD. Nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase, NOX) has been indicated in Aβ pathology; however, whether and how it affects tau pathology are not yet clear. Methods: The role of NOX2 in cognitive function, amyloid plaque formation, and tau hyperphosphorylation were examined in APP/PS1 transgenic mice mated with p47phox-deficient mice (with deletion of the gene of neutrophil cytosolic factor 1, Ncf1) and/or in p47phox-deficient mice receiving intracerebroventricular (ICV) injection of streptozotocin (STZ). The cognitive and non-cognitive functions in these mice were assessed by Morris water maze, Rotarod test, open field, and elevated plus maze. Aβ levels, amyloid plaques, p47phox expression, and astrocyte activation were evaluated using immunofluorescence staining, ELISA, and/or Western blotting. Cultured primary neuronal cells were treated with okadaic acid or conditioned media (CM) from high glucose-stimulated primary astrocytes. The alteration in tau pathology was determined using Western blotting and immunofluorescence staining. Results: Deletion of the gene coding for p47phox, the organizer subunit of NOX2, significantly attenuated cognitive impairment and tau pathology in these mice. p47phox deficiency decreased the activation of astrocytes but had no effect on Aβ levels and amyloid plaque formation in the brains of aged APP/PS1 mice, which displayed markedly increased expression of p47phox in neurons and astrocytes. Cell culture studies found that neuronal p47phox deletion attenuated okadaic acid-induced tau hyperphosphorylation at specific sites in primary cultures of neurons. CM from high glucose-treated WT astrocytes increased tau hyperphosphorylation in primary neurons, whereas this effect was absent from p47phox-deficient astrocytes. Conclusions: These results suggest that p47phox is associated with cognitive function and tau pathology in AD. p47phox expressed in neurons contributes to tau hyperphosphorylation directly, while p47phox in astrocytes affect tau hyperphosphorylation by activating astrocytes indirectly. Our results provide new insights into the role of NOX2 in AD and indicate that targeted inhibition of p47phox may be a new strategy for the treatment of AD. [ABSTRACT FROM AUTHOR]

The female sex is traditionally considered a favorable prognostic factor for nasopharyngeal carcinoma (NPC). However, no particular study has reported this phenomenon. To explore the prognostic impact of gender on patients with NPC after definitive radiotherapy, we reviewed the clinical data of 2063 consecutive patients treated between 1st January 2000 and 31st December 2003 in the Sun Yat-sen University Cancer Center. The median follow-up for the whole series was 81 months. The female and male patients with early stage disease comprised 49.4% and 28.1% of the patient population, respectively. Both the 5-year overall survival (OS) and disease-specific survival (DSS) rates of female patients were significantly higher than those of male patients (OS: 79% vs. 69%, P < 0.001; DSS: 81% vs. 70%, P < 0.001). For patients with locoregionally advanced NPC, the 5-year OS and DSS rates of female vs. male patients were 74% vs. 63% (P < 0.001) and 76% vs. 64%, respectively (P < 0.001). A multivariate analysis showed that gender, age, and TNM stage were independent prognostic factors for the 5-year OS and DSS of NPC patients. The favorable prognosis of female patients is not only attributed to the early diagnosis and treatment but might also be attributed to some intrinsic factors of female patients.