Neuroscience
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The prominent morphometric alterations of Alzheimer's disease (AD) occur both in gray matter and in white matter. Multimodal fusion can examine joint information by combining multiple neuroimaging datasets to identify the covariant morphometric alterations in AD in greater detail. ⋯ The joint IC maps revealed that the simultaneous changes in the gray matter and FA values primarily involved the following areas: (1) the temporal lobe/hippocampus-cingulum, (2) the frontal/cingulate gyrus-corpus callosum, and (3) the temporal/occipital/parietal lobe-corpus callosum/corona radiata. Our findings suggest that gray matter atrophy is associated with reduced white matter fiber integrity in AD and possibly expand the understanding of the neuropathological mechanisms in AD.
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While spinal cord astrocytes play a key role in the generation of cancer pain, there have been no studies that have examined the relationship of tumor-induced astrocyte activation and aromatase expression during the development of cancer pain. Here, we examined tumor-induced mechanical hyperalgesia and cold allodynia, and changes in Glial fibrillary acid protein (GFAP) and aromatase expression in murine models of painful and non-painful bone cancer. We demonstrate that implantation of fibrosarcoma cells, but not melanoma cells, produces robust mechanical hyperalgesia and cold allodynia in tumor-bearing mice compared to saline-injected controls. ⋯ Finally, administration of an aromatase inhibitor reduced tumor-induced hyperalgesia in fibrosarcoma-bearing animals. We conclude that a painful fibrosarcoma tumor induces a significant increase in spinal astrocyte activation and aromatase expression and that the up-regulation of aromatase plays a role in the development of bone tumor-induced hyperalgesia. Since spinal aromatase is also upregulated, but to a lesser extent, in non-painful melanoma bone tumors, it may also be neuroprotective and responsive to the changing tumor environment.
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Neurodegenerative diseases are difficult to study due to unavailability of human neurons. Cell culture systems and primary rodent cultures have shown to be indispensable to clarify disease mechanisms and provide insights into gene functions. Nevertheless, it is hard to translate new findings into new medicines. ⋯ Addition of C6 glioma conditioned medium improved the bursting frequency of cells without further maturation or evidence for glutamatergic responses. Furthermore, cells were suitable for lentiviral transduction within the tested time frame. Altogether, iCell® neurons might be useful to model neurodegenerative diseases in which young GABAergic subtypes are affected.
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Converging data in songbirds support a central role for the medial preoptic nucleus (POM) in motivational aspects of vocal production. Recent data suggest that dopamine in the POM plays a complex modulatory role in the production of sexually-motivated song and that an optimal level of dopamine D1 receptor stimulation is required to facilitate singing behavior. To further explore this possibility, we used quantitative real-time PCR to examine relationships between mRNA expression of D1 as well as D2 receptors in the POM (and also the lateral septum and Area X) and sexually-motivated singing behavior in male European starlings. ⋯ Analysis of birds with low and intermediate levels of D1 expression in POM revealed strong positive correlations between D1 expression and song but negative relationships between D2 receptor expression and song. These findings support prior work suggesting an optimal level of POM D1 receptor stimulation best facilitates sexually-motivated singing behavior. Results also suggest that D2 receptors may work in opposition to D1 receptors in POM to modify vocal production.
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The human brain is composed of complex networks of 100 billion neurons that underlie its higher functions. The set of neural connections in the brain has recently attracted growing interest from the scientific community. It is important to identify individual differences in these neural connections to study the background of individual differences in brain function and performance. ⋯ There were no large differences in the Euclidean distance among different combinations of scanners used or between image pairs with and without scanner upgrade. The results indicate that brain diffusivity can identify a specific individual; i.e., the pattern of brain diffusion is personally identifiable information. Individual differences in brain diffusivity will form the basis of individual differences in personality and brain function.