Publications by authors named "Edison K Miyawaki"

Background And Objectives: Among infectious etiologies of encephalitis, herpes simplex virus type 1 (HSV-1) is most common, accounting for ∼15%-40% of adult encephalitis diagnoses. We aim to investigate the association between immune status and HSV encephalitis (HSVE). Using a US Medicaid database of 75.

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Is the cerebrum involved in its own activation to states of attention or arousal? "Telencephalon" is a term borrowed from embryology to identify not only the cerebral hemispheres of the forebrain, but also the basal forebrain. We review a generally undercited literature that describes nucleus basalis of Meynert, located within the substantia innominata of the ventrobasal forebrain, as a telencephalic extension of the ascending reticular activating formation. Although that formation's precise anatomical definition and localization have proven elusive over more than 70 years, a careful reading of sources reveals that there are histological features common to certain brainstem neurons and those of the nucleus basalis, and that a largely common dendritic architecture may be a morphological aspect that helps to define non-telencephalic structures of the ascending reticular activating formation (e.

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The association between idiopathic Parkinson's disease, a paradigmatic dopamine-deficiency syndrome, and problems in the estimation of time has been studied experimentally for decades. I review that literature, which raises a question about whether and if dopamine deficiency relates not only to the motor slowness that is an objective and cardinal parkinsonian sign, but also to a compromised neural substrate for time perception. Why does a clinically (motorically) significant deficiency in dopamine play a role in the subjective perception of time's passage? After a discussion of a classical conception of basal ganglionic control of movement under the influence of dopamine, I describe recent work in healthy mice using optogenetics; the methodology visualizes dopaminergic neuronal firing in very short time intervals, then allows for correlation with motor behaviors in trained tasks.

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We describe an acute, postoperative dysarthria-facial paresis. While the rare stroke syndrome has been described previously, we present an under-described clinical nuance to its presentation with a particularly clear imaging correlation. A 78-year-old, right-handed man with a past medical history of aortic stenosis presented after a transcatheter aortic valve replacement.

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Background And Purpose: Fibrosing inflammatory pseudotumor (FIP) of the nasopharynx is a rare nonneoplastic inflammatory lesion that is frequently mistaken for malignancy or infection. It is often misdiagnosed by radiologists as nasopharyngeal carcinoma or lymphoma, resulting in multiple biopsies and delays in diagnosis. The purpose is to understand trends in clinical presentation, imaging findings, treatment modalities, and patient outcomes of nasopharyngeal FIP.

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Clasmatodendrosis derives from the Greek for fragment (), tree (), and condition (). Cajal first used the term in 1913: he observed disintegration of the distal cell processes of astrocytes, along with a fragmentation or beading of proximal processes closer to the astrocyte cell body. In contemporary clinical and experimental reports, clasmatodendrosis has been observed in models of cerebral ischemia and seizures (including status epilepticus), in elderly brains, in white matter disease, in hippocampal models and cell cultures associated with amyloid plaques, in head trauma, toxic exposures, demyelinating diseases, encephalitides and infection-associated encephalopathies, and in the treatment of cancer using immune effector cells.

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We report two cases of biopsy-corroborated "fibrosing inflammatory pseudotumor" to illustrate that the entity, rarely described in the neurological literature, should be included in the differential diagnosis of either a cranial mononeuropathy or, certainly, in the case of progressive cranial neuropathies. A broad differential diagnosis arises in certain contexts. Early steroid treatment can be effective, and perhaps later-generation immune-modulating agents may confer further options, although there is no known definitive treatment.

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