World Neurosurg
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Comparative Study
Determination of relevant neuron-neuron connections for neural prosthetics using time-delayed mutual information: tutorial and preliminary results.
Identification of functional dependence among neurons is a necessary component in both the rational design of neural prostheses as well as in the characterization of network physiology. The objective of this article is to provide a tutorial for neurosurgeons regarding information theory, specifically time-delayed mutual information, and to compare time-delayed mutual information, an information theoretic quantity based on statistical dependence, with cross-correlation, a commonly used metric for this task in a preliminary analysis of rat hippocampal neurons. ⋯ Comparison of time-delayed MI to cross-correlation in identification of functionally dependent neurons indicates that the methods are not equivalent. Time-delayed MI appeared to capture some interactions between CA3-CA1 neurons at physiologically plausible time delays missed by cross-correlation. It should be considered as a method for identification of functional dependence between neurons and may be useful in the development of neural prosthetics.
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To evaluate the predictive ability of the original ICH Score (oICH) in a large independent cohort of patients with arteriovenous malformation-associated intracerebral hemorrhage (AVM-ICH), an important cause of intracerebral hemorrhage (ICH) that is associated with significantly different epidemiology, clinical course, and outcome compared with primary ICH. ⋯ oICH is a valid clinical grading scale with high predictive accuracy for functional outcome after AVM-ICH. It is unclear whether the score is appropriate for risk stratification with regard to mortality because of the low risk of death associated with AVM-ICH. Simple adjustments of the age and ICH volume cutoff points improve performance of the score and reduce the probability of overestimating a patient's risk of an unfavorable outcome after AVM-ICH.
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Comparative Study
Novel animal glioma models that separately exhibit two different invasive and angiogenic phenotypes of human glioblastomas.
Invasive behaviors of malignant gliomas are fundamental traits and major reasons for treatment failure. Delineation of invasive growth is important in establishing treatment for gliomas and experimental neuro-oncology could benefit from an invasive glioma model. In this study, we established two new cell line-based animal models of invasive glioma. ⋯ These animal models histologically recapitulated two invasive and angiogenic phenotypes, namely angiogenesis-dependent and angiogenesis-independent invasion, also observed in human glioblastoma. These cell lines provided a reproducible in vitro and in vivo system to analyze the mechanisms of invasion and angiogenesis in glioma progression.