Evaluation of the good tumor response of embryonal tumor with abundant
neuropil and true rosettes.
The remodeling of the
neuropil induced by ICH is as described in (b).
Here, it is also likely that the position of the guide cannula for the microinjection let the substances spread from the medial border of the MePD through its
neuropil, and the coarse axons of the optic tract, situated in the back of the microinjection site, might have limited drug diffusion outside the MePD.
Aggregates of abnormally hyperphosphorylated MAPT are the main constituent of neurofibrillary tangles (NFTs) and
neuropil threads (NTs) that are characteristic neuropathological hallmark lesions of Alzheimer's disease (AD) [17, 18].
(8) As the connections between neurons (the
neuropil) are progressively lost in the aging brain, so are memory, sensory learning, and neuroplasticity.
[9,16] The increase in volume noted in the nucleus ovoidalis in the auditory stimulated groups could be due to the observed increase in its neuronal number as well as changes in the
neuropil. The changes in the
neuropil can be further determined by studying the dendritic and axonal profiles of the nucleus ovoidalis.
When tau is hyperphosphorylated, primarily by the action of serine/threonine kinases, it dissociates from microtubules, leading to the formation of paired helical fragments that, in turn, aggregate into neurofibrillary tangles and
neuropil threads (4).
[58] Braak and Braak [59] proposed a predictive model of the progressive stages of AD based on the distribution of neurofibrillary tangles (NFT) and
neuropil threads found in brain autopsies.
The monkeys that received a higher dose and died at 67 and 132 DPI showed marked liquefactive necrosis of the cerebrum with formation of variable sized irregular cystic cavities lined by atrophied parenchymal septa, containing remnants of
neuropil (Figure 3) and chronic inflammatory cells, predominantly fibroblasts.
Histopathologically, while most prion diseases, including CJD, BSE, CWD, and most of scrapie cases (i.e., the classic transmissible spongiform encephalopathies or TSEs), are characterized by the triad of spongiform change, gliosis, and neuronal loss, some rare but very informative variants such as FI, GSS, or PrP-CAA may show very subtle or even absent spongiform change or be characterized by prominent extracellular amyloid plaques accumulating either in the
neuropil or around blood vessels.
Treatment-responsive limbic encephalitis identified by
neuropil antibodies: MPJ and PET correlates.
The generalized histopathology reveals spongiform degeneration in the
neuropil of the brain and spinal cord.