Search results for "Human brain"
showing 10 items of 97 documents
Back to Pupillometry: How Cortical Network State Fluctuations Tracked by Pupil Dynamics Could Explain Neural Signal Variability in Human Cognitive Ne…
2017
Visual Abstract
Human brain organoids assemble functionally integrated bilateral optic vesicles
2021
During embryogenesis, optic vesicles develop from the diencephalon via a multistep process of organogenesis. Using induced pluripotent stem cell (iPSC)-derived human brain organoids, we attempted to simplify the complexities and demonstrate formation of forebrain-associated bilateral optic vesicles, cellular diversity, and functionality. Around day 30, brain organoids attempt to assemble optic vesicles, which develop progressively as visible structures within 60 days. These optic vesicle-containing brain organoids (OVB-organoids) constitute a developing optic vesicle's cellular components, including primitive corneal epithelial and lens-like cells, retinal pigment epithelia, retinal progeni…
Neurofibrillary tangles and neuropil threads as a cause of dementia in Parkinson’s disease
1997
Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most common age-related degenerative disorders of the human brain. Both diseases involve multiple neuronal systems and are the consequences of cytoskeletal abnormalities. In AD susceptible neurons produce neurofibrillary changes, while in Parkinson’s disease, they develop Lewy bodies. In AD six developmental stages can be distinguished on account of the predictable manner in which the neurofibrillary changes spread across the cerebral cortex. During the course of PD numerous limbic determined parts of the brain undergo specific lesions regulating endocrine and autonomic functions. In general, the extranigral destructions are in t…
Preservation of glial cytoarchitecture from ex vivo human tumor and non-tumor cerebral cortical explants: A human model to study neurological diseases
2007
For the human brain, in vitro models that accurately represent what occurs in vivo are lacking. Organotypic models may be the closest parallel to human brain tissue outside of a live patient. However, this model has been limited primarily to rodent-derived tissue. We present an organotypic model to maintain intraoperatively collected human tumor and non-tumor explants ex vivo for a prolonged period of time (similar to 11 days) without any significant changes to the tissue cytoarchitecture as evidenced through immunohistochemistry and electron microscopy analyses. The ability to establish and reliably predict the cytoarchitectural changes that occur with time in an organotypic model of tumor…
Membrane-type 1 metalloproteinase is upregulated in microglia/brain macrophages in neurodegenerative and neuroinflammatory diseases
2013
We previously reported that glioma cells induce the expression of membrane-type 1 metalloproteinase (MT1-MMP or MMP-14) in tumor-associated microglia/macrophages and promote tumor growth, whereas MMP-14 expression in microglia under physiological conditions is very low. Here, we show that the increase in MMP-14 expression is also found in microglia/macrophages associated with neurodegenerative and neuroinflammatory pathologies in mouse models as well as in human biopsies or post-mortem tissue. We found that microglial/macrophage MMP-14 expression was upregulated in Alzheimer's disease tissue, in active lesions of multiple sclerosis, and in tissue from stage II stroke as well as in the corre…
Klinische Aspekte der "argyrophilic grain disease"
2000
Argyrophilic grain disease (AGD) is a frequently occurring degenerative illness of the aging human brain. It is accompanied by progressive pathological alterations of the cytsokeleton which are traceable to an abnormal phosphorylation of the microtubule associated tau protein. Histologically, it is possible with the help of suitable staining techniques to identify pathognomonic spindle-shaped cellular inclusions (argyrophilic grains). These cellular inclusions display a typical cortical as well as subcortical distribution pattern. The goal of the present study is the retrospective evaluation of the clinical findings from 53 individuals with neuropathologically demonstrable AGD-related chang…
An improved anatomical MRI technique with suppression of fixative fluid artifacts for the investigation of human postmortem brain phantoms
2016
PURPOSE Phantoms are often used to assess MR system stability in multicenter studies. Postmortem brain phantoms best replicate human brain anatomy, allowing for a combined assessment of the MR system and software chain for data analysis. However, a wash-out of fixative fluid affecting T1 values and thus T1-weighted sequences such as magnetization-prepared 180 degrees radiofrequency pulses and rapid gradient-echo (MP-RAGE) has been reported for brain phantoms, hampering their immediate use. The purpose of this study was the creation of anatomical data that provide the characteristics of conventional data while avoiding this artifact. THEORY AND METHODS Two brain phantoms were scanned at seve…
Uptake of polymeric nanoparticles in a human induced pluripotent stem cell-based blood-brain barrier model: Impact of size, material, and protein cor…
2021
The blood–brain barrier (BBB) maintains the homeostasis of the central nervous system, which is one of the reasons for the treatments of brain disorders being challenging in nature. Nanoparticles (NPs) have been seen as potential drug delivery systems to the brain overcoming the tight barrier of endothelial cells. Using a BBB model system based on human induced pluripotent stem cells (iPSCs), the impact of polymeric nanoparticles has been studied in relation to nanoparticle size, material, and protein corona. PLGA [poly(lactic-co-glycolic acid)] and PLLA [poly(d,l-lactide)] nanoparticles stabilized with Tween® 80 were synthesized (50 and 100 nm). iPSCs were differentiated into human brain m…
229 – ERBB4 genotype effects on human brain structure
2008
Background:Disturbed functional and structural brain connectivity in schizophrenia has been shown in a large number of studies. There is evidence from several neuroimaging and post mortem studies that altered neuronal myelination may in part account for this deficit. Recent investigations have suggested that variations of the genes that encode the Neuregulin 1 (NRG1) ErbB4 receptor complex might be associated with schizophrenia illness. As NRG1 and ErbB4 have been implicated in myelination and neuronal proliferation. We investigated whether cerebral micro and macrostructure is predicted by two risk haplotypes of the ErbB4 gene. Methods: The effects of two single-nucleotide polymorphisms (SN…