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M Earnest

Publications and source records attributed to M Earnest.

4 recordsLinked to original sources

Cytochrome oxidase in the human visual cortex: distribution in the developing and the adult brain.

Cytochrome-oxidase (CO) histochemistry has revealed important functional subdivisions, modules, and processing streams in the macaque visual cortex. The present study is aimed at analyzing the development and characteristics of CO patterns in the human visual cortex by means of histochemistry and immunohistochemistry. At 26 weeks of gestation, both the ventricular and subventricular zones had low levels of CO, while the cortical plate had moderate levels of CO. At birth, supragranular CO-rich zones (puffs) were not clearly organized, indicating that the development of puffs in the neonatal striate cortex lags behind that of the macaque monkey, whose puffs appear weeks before birth. Puffs were more clearly discernible in human cortex at postnatal day 24, and became well organized by the fourth postnatal month. Layer IVc alpha in the neonate exhibited a higher level of activity and amount of CO than the central portion of IVc beta, which contained a dense aggregate of small neurons. The base of IVc beta, however, was often as CO reactive as IVc alpha. In contrast, the majority of specimens available to us from the fourth postnatal month and from adults with no known neurological diseases had significantly greater CO reactivity in layer IVc beta than in IVc alpha. Layer VI was moderately reactive for CO throughout development. In V2, stripes with globular zones of high CO activity were sporadically present at birth, suggesting that their development may parallel or precede that of puffs in V1. These stripes with CO-rich globular zones became more prominent in the adult and radiated orthogonally from the V1/V2 border. They were not, however, clearly organized into alternating thick and thin stripes as they are in the squirrel monkey. Visual cortical areas beyond V2 exhibited high CO activity mainly in layers III and IV and moderate levels in VI, suggesting that sites associated with cortico-cortical pathways may be metabolically most active.

Adult↗

Primary non-traumatic intracranial hemorrhage. A municipal emergency hospital viewpoint.

The devastating natural history of 138 consecutive admissions for non-traumatic intracranial hemorrhage to a major emergency care municipal hospital is reviewed. Sixty-four percent of the patients had demonstrable intracranial hematomas while 36% had mainly subarachnoid hemorrhage. Hypertension was a related condition in 43% of the parenchymal hematoma patients, while proved aneurysms accounted for 74% of the subarachnoid hemorrhage patients. There was only a 14% survivorship for patients requiring emergent surgery. All operated hematoma patients survived delayed surgery with improved level of responsiveness. The overall mortality was 74% for intracranial hematoma patients and 58% for aneurysm-caused subarachnoid hemorrhage patients.

Adult↗

Disappearing carotid defects.

Large intraluminal cervical carotid artery filling defects consistent with mural thrombi were angiographically demonstrated during acute hemispheric neurologic episodes. These thrombi disappeared benignly as shown by serial angiography in 2 patients treated with intravenous heparin and spontaneously in 1 patient treated surgically. Thus, partially obstructing cervical carotid artery thrombi may lyse either with the use of anticoagulant therapy or else spontaneously. The etiology of the thrombi may partly be related to underlying atheromatous disease.

Aged↗