This view is supported by, for example, findings that ovariectomy in younger women (i.e. prior to menopause) significantly increases the risk for the development of memory problems and AD in later life. However,
the biological basis underlying these cognitive changes is still poorly understood. Our aim in the current study was to understand the interactive effects of acute, learn more pharmacological-induced menopause (after Gonadotropin Hormone Releasing Hormone agonist (GnRHa) treatment) and scopolamine (a cholinergic antagonist used to model the memory decline associated with aging and AD) on brain functioning. To this end we used fMRI to study encoding during a Delayed Match to Sample (DMTS) (visual working memory) task. We report a relative attenuation in BOLD response brought about by scopolamine in regions that included bilateral prefrontal cortex find more and the left parahippocampal gyrus. Further, this was greater in women post-GnRHa than in women whose ovaries were functional. Our results also indicate that following pharmacological-induced menopause, cholinergic depletion produces a more significant behavioural deficit in overall memory performance, as manifest by increased response time. These findings suggest that acute loss of ovarian hormones exacerbate the effects of cholinergic depletion on a memory-related, behavioural measure, which is dependent on fronto-temporal brain
regions. Overall, our findings point to a neural network by which acute loss of ovarian function may interact to negatively impact encoding. (C) 2010 Elsevier Ltd. All rights reserved.”
“Papillomaviruses are associated with benign and malignant neoplasias of the skin and mucous membranes. The sequence of a novel canine papillomavirus was determined from DNA detected in the oral cavity of a dog. The sequence of the
novel virus canine papillomavirus type 13 (CPV13) shares the highest levels of similarity with the Tau papillomaviruses CPV2 and CPV7.”
“Alzheimer’s disease (AD) is a progressive, neurodegenerative disease characterized by cell and synapse losses and the ensued network disconnections. Olfactory impairment is common and occurs early in AD patients, suggesting its potential role in the early diagnosis of AD. However, the functional connectivity of the olfactory www.selleck.cn/products/AZD6244.html system in AD has received little attention. Using local field potentials symmetrically recorded from the two olfactory bulbs in awake mice, we found that in AD model mice with robust amyloid-beta burden, the coherence between the two bulbs for spontaneous activities was significantly lower in all of the four frequency bands (theta, beta, low and high gamma: 2-12, 15-35, 35-65 and 65-100 Hz, respectively). Moreover, the coherence for odor-evoked activities was also lower, particularly in the beta band, when compared to their wild-type littermates.