Autopsy findings after intracranial thrombectomy for acute ischemic stroke: a clinicopathologic study of 5 patients.

BACKGROUND AND PURPOSE: Endovascular thrombectomy is an increasingly used treatment for arterial occlusion in acute stroke. Various devices (including most extensively the Mechanical Embolus Removal in Cerebral Ischemia [MERCI] Retriever device) have been used for this. METHODS: We review the neuropathologic findings in 5 patients (age range, 59 to 87 years) who died acutely or as late as 38 days after procedures using the MERCI (4 patients) and Penumbra (1 patient) devices were carried out to remove thromboemboli from the middle cerebral artery. Partial recanalization was achieved by thrombectomy in all 5 patients. RESULTS: All patients showed extensive cerebral infarcts, 3 of 5 with clinical hemorrhagic transformations of the infarct or frank intraparenchymal hemorrhage after thrombectomy; in 1 case, this was judged to be at least partly on the basis of concomitant hypertensive microvascular disease. With 1 exception, basal arteries examined in detail by immunohistochemistry showed prominent, although usually nonocclusive (and generally nonulcerated), atheromata, often with significant luminal stenosis. One patient showed a subintimal dissection with resultant occlusion of the middle cerebral artery. CONCLUSIONS: In this highly selected group of patients, the vascular pathological abnormalities affecting basal arteries were variable, but complicated atherosclerosis was a common finding. Extensive irreversible brain necrosis before therapeutic procedures may have contributed to deaths.

Differential lectin histochemical studies on lipofuscin (age-pigment) and on selected ceroid pigments.

The persistent indiscriminate use of the term lipofuscin for the pigments encountered in pathological conditions, and which should be most properly termed ceroid pigments, is still creating unnecessary conceptual and nomenclature problems, and a great deal of confusion. While both the age-dependent lipofuscin and the pathologically formed ceroid pigments have somewhat similar physical and histochemical properties, sufficient differences to properly identify these two types of pigments are presented in this communication. In addition, because little is known on the saccharide components of lipofuscin and ceroid pigments in situ, we have in recent years explored the lectin binding characteristics of lipofuscin in human and rats, as well as in diverse ceroid pigments experimentally induced in rats. Our lectin histochemical results showed qualitative and quantitative differences in the saccharide composition between human cerebral neurolipofuscin and the intra and extracellular ceroid pigment of human atheromas, as well as, between rat lipofuscin and the ceroid pigments induced in these animals.

Sequential histochemical studies of neuronal lipofuscin in human cerebral cortex from the first to the ninth decade of life.

The typical and most consistent physico-histochemical properties of lipofuscin granules, such as autofluorescence, sudanophilia, acid-fastness, PAS-reactivity, and lectin reactivities for diverse saccharide moieties have been generally detected in tissue specimens of old humans and animals. The purpose of this study was, therefore, to explore possible sequential variations of each of these properties in cortical neurons of the left cerebral temporo-parietal areas from individuals dying from the first to the ninth decade. Autofluorescence was studied with an ad hoc equipped microscope, sudanophilia was evaluated by Oil-red-O (ORO) staining, acid-fastness by long Ziehl-Nielsen reagent, PAS reactivity by the periodic-acid-Schiff reagent before and after diastase treatment, and the saccharide moieties by the use of a commercial kit of seven different biotinylated lectins. In the specimen from a 5-year-old child, lipofuscin granules were detected in less than 5% of the cortical neurons, but these granules already showed golden-yellow autofluorescence, sudanophilia, acid-fastness and PAS-reactivity. From the second to the ninth decade of life, perikaryal lipofuscin granules were found in practically all cortical neurons with apparent agewise increases in the intensity of sudanophilia and PAS-reactivity, but with variable acid-fastness expression. Surprisingly, however, no saccharide residues were detected by lectin histochemistry before the fifth decade of life. First detected saccharide was mannose in specimens from the fifth decade of life, and at later decades acetyl galactosamine, sialic acid and lactose were also found. Although, the reasons for the absence of lipofuscin affinity for the seven lectins used in this study in the cortical neurons of young and middle-aged individuals are presently unknown, these unexpected findings suggested important evolutionary changes of biogenesis and composition of the age-pigment.

Modulación nutricional y enzimática del epitelio pigmentario retinal: efectos de la Lovastatin y de la Leupeptina sobre la cardiogénesis en el epitelio pigmentario retinal de ratas jóvenes deficientes y suplementadas con vitamina E / Nutritional and enzymatic modulation of the retinal pigmentary epithelium: effects of the lovastatin and the leupeptin on cardiogenesis of vitamin E deficient and supplemented young rats

El objetivo del presente trabajo es el estudio de la acción de un inhibidor de la 3-hidroxi-3-metil glutaril coenzima A reductasa [Lovastatin] y de un inhibidor de las proteasas [leupeptina] sobre el depósito de lipopigmentos autofluorescentes [ceroide] en el epitelio pigmentario de retina [RPE] de ratas deficientes de vitamina E y suplementadas con 16 mg p.cto. de dl-alfa-acetato de tocoferol. Las ratas deficientes de vitamina E y las que recibieron dieta suplementada con dl-alfa-acetato de tocoferol fueron subdivididas, unas recibieron por un período de 8 semanas, dietas con 2.1 y 0.5 g de Lovastatin/kg de dieta, mientras que las ratas del otro grupo fueron tratadas con una infusión peritoneal constante de 0.5 mg/día de leupeptina mediante minibombas osmóticas [Alzet 2002] implantadas consecutivamente a los 15, 30 y 45 días. Las ratas deficientes en vitamina E tratadas con leupeptina presentaron un aumento considerable en la autofluorescencia del RPE respecto del resto de los grupos. (AU)

Modulación nutricional y enzimática del epitelio pigmentario retinal: efectos de la Lovastatin y de la Leupeptina sobre la cardiogénesis en el epitelio pigmentario retinal de ratas jóvenes deficientes y suplementadas con vitamina E / Nutritional and enzymatic modulation of the retinal pigmentary epithelium: effects of the lovastatin and the leupeptin on cardiogenesis of vitamin E deficient and supplemented young rats

El objetivo del presente trabajo es el estudio de la acción de un inhibidor de la 3-hidroxi-3-metil glutaril coenzima A reductasa [Lovastatin] y de un inhibidor de las proteasas [leupeptina] sobre el depósito de lipopigmentos autofluorescentes [ceroide] en el epitelio pigmentario de retina [RPE] de ratas deficientes de vitamina E y suplementadas con 16 mg p.cto. de dl-alfa-acetato de tocoferol. Las ratas deficientes de vitamina E y las que recibieron dieta suplementada con dl-alfa-acetato de tocoferol fueron subdivididas, unas recibieron por un período de 8 semanas, dietas con 2.1 y 0.5 g de Lovastatin/kg de dieta, mientras que las ratas del otro grupo fueron tratadas con una infusión peritoneal constante de 0.5 mg/día de leupeptina mediante minibombas osmóticas [Alzet 2002] implantadas consecutivamente a los 15, 30 y 45 días. Las ratas deficientes en vitamina E tratadas con leupeptina presentaron un aumento considerable en la autofluorescencia del RPE respecto del resto de los grupos.