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H Braak

Publications and source records attributed to H Braak.

At least 163 records · Page 9Linked to original sources
PubMed1982

[The packing density of supragranular pigment-laden stellate cells in phylogenetically older and newer portions of the human telencephalic cortex].

Conspicuous pigment deposits which can be intensely stained by aldehydefuchsin characterize a type of small stellate cell. These can mainly be found in the supragranular layers (layers II and III) of the human isocortex. The packing density of these cells has been evaluated in different cortical areas. The blocks used were cut out of the brain in such a manner as to include phylogenetically older parts of the cortex, fields of intermediate differentiation, and mature isocortex. The counting results verify a gradual increase in the packing density of the supragranular pigment-laden stellate cells from phylogenetically older to newer portions of the telencephalic cortex.

Astrocytes↗
PubMed1982

Morphologic studies on adult neuronal-ceroid lipofuscinosis (NCL).

This report concerns morphologic findings in two middle-aged women, who died of sporadic adult neuronal ceroid-lipofuscinosis (NCL) and whose brains were studied histologically, by electron microscopy and by pigmentoarchitectonic techniques. In addition, the brain of a 35-year-old woman, who died of familial protracted juvenile NCL, was also investigated using pigmentoarchitectonic methods. Clinical, light and electron microscopic findings were compatible with the above-mentioned diagnosis. Pigmentoarchitectural analysis of homotypical isocortex in these three brains revealed (1) loss of pigment-laden stellate cells in layer II, (2) axonal enlargements of layer IIIab-pyramidal cells, and (3) considerable cell loss in layer Va. The changes were more pronounced in the brain affected by protracted juvenile NCL than in the two brains affected by adult NCL. The study emphasizes the value of the pigmentoarchitectonic technique, both in diagnostic neuropathology and in ascertaining patients afflicted with adult NCL. The ultrastructure of the lipopigments showed a motley spectrum of membrane formation such as curvilinear, fingerprint, or straight membranes and was less granular than regular senile lipofuscin.

Adult↗
PubMed1981

On the nucleus endymalis of the human thalamus.

In the present article the shape and extent of the nucleus endymalis in the human thalamus is described. By means of a newly developed method of selective staining of intracellular lipofuscin granules with aldehydefuchsin it is possible to examine the three-dimensional shape of the griseum in complete series of 800 micrometer thick slices. The nucleus endymalis can be divided into an invariably occurring strongly pigmented caudal pars pigmentosa with clear-cut boundaries and an oral pars commissuralis. The weakly pigmented oral part is only found in brains with developed massa intermedia and varies considerably from individual to individual. The pars pigmentosa is characterized by its periventricular position medial to the nucleus parafascicularis. Differences in nomenclature and outlines of topographically corresponding thalamic nuclei of other authors are discussed. It is assumed that the pars pigmentosa a least partly corresponds to the catecholaminergic cell group A11 in the rat brain (Dahlström and Fuxe 1964). Finally, its possible functional connections to the dorsal periventricular bundle and its significance for stimulation-produced analgesia (SPA) in man are discussed.

Aged↗
PubMed1980

Biomathematical analysis of the neuronal loss in the aging human brain of both sexes, demonstrated in pigment preparations of the pars cerebellaris loci coerulei.

The pars cerebellaris loci coerulei is a flat accumulation of perikarya representing a subnucleus of the locus coeruleus in the roof of the fourth ventricle of the brain in man. A quantitative study was done on this subnucleus; it comprised 67 specimens from individuals between 11 and 90 years. Nerve cell counts were performed on cleared mounted block preparations. Mathematical analysis of the data was performed using logistic growth functions. The results showed that with advancing age there is a loss of neurons in both sexes. This begins in the female approximately after age 40; in the male already at age 20 (reaching a lower value in old age). The final loss of neurons is more pronounced in the male than in the female. Male and female specimens did not differ in the total number of neurons. In both sexes the left side of the pars cerebellaris loci coerulei contained more neurons than the right.

Adolescent↗
PubMed1980

Age-related alterations of the proximal axon segment in lamina IIIab-pyramidal cells of the human isocortex. A Golgi and fine structural study.

In the human isocortex preferably the pyramidal cells of layer IIIab are subjected to a conspicuous age-related alteration in that they develop spindle-shaped enlargements of their proximal axon segment. In Golgi impregnations such IIIab-pyramidal cells with an axon dilatation do not display obvious alterations in the ramification or spine density of their dendrites. Electron microscopically different degrees of this alteration can be recognized; beginning with a cone-shaped and slight dilatation and culminating in a giant spindle-shaped enlargement of the proximal axon segment. The fasciculated microtubules normally characterizing the initial segment are pushed aside or are lacking. Lipofuscin granules, RER cisterns and ribosome rosettes penetrate into the dilatation. The axolemma of those parts of the axon segment in the vicinity of which lipofuscin granules can be encountered lacks a dense axolemmal undercoating. As concerns the adjacent profiles of the dilatation there are no obvious alterations in comparison to a normal proximal axon segment. A slender process arises distally from the dilatation showing the morphological characteristics of the axon initial segment.

Aged↗
PubMed1979

Spindle-shaped appendages of IIIab-pyramids filled with lipofuscin: a striking pathological change of the senescent human isocortex.

Brains from 30 mentally normal men, ranging in age from 18--90 years, were studied to assess the occurrence and development of lipofuscin-filled spindle-shaped appendages of pyramidal cells of the isocortex; these can generally be encountered in the senescent brain within layer IIIab. The number of pigmented spindles was determined in a circumscribed part of prefrontal area revealing a close association of this conspicuous pathological alteration with growing age.

Adolescent↗
PubMed1979

Pigmentoarchitectonic pathology of the isocortex in juvenile neuronal ceroid-lipofuscinosis: axonal enlargements in layer IIIab and cell loss in layer V.

Pigment preparations of 800 micrometer thickness and Golgi studies of the isocortex in juvenile neuronal ceroid-lipofuscinosis, morphologically proven by electron microscopy, revealed: 1. giant axonal dilatations of IIIab-pyramids. These expansions exceeded by far those found in pyramidal cell axons of other isocortical layers. 2. severe numerical reduction of neurons in the ganglionic layer.

Adolescent↗
PubMed1979

Pigment architecture of the human telencephalic cortex. IV. Regio retrosplenialis.

Cortical lamination and parcellation of the retrosplenial region in the human brain is evaluated with the aid of frontal serial sections stained for nerve cells (15 micrometers), myelin sheaths (100 micrometers), and lipofuscin granules (800 micrometers). For the most part, the retrosplenial region is buried in the depth of the sulcus corporis callosi covering the posterior parts of the cingulate gyrus. It lies between the supracallosal derivatives of the allocortex (fascia dentata, cornu ammonis, subiculum) and the mature parietal isocortex. The region can be subdivided into five areas. The transitory periallocortical area ectosplenialis is followed by a richly differentiated proisocortical core displaying extremely externopyramidal, externoteniate, and astriate to unitostriate characteristics. The parvocellular core is averagely poor in pigment (typus clarus) and rich in myelinated fibres (typus dives). Minor structural differences allow for its subdivision into a lateral, an intermediate and a medial retrosplenial field. The accompanying area parasplenialis is adjacent to the equoteniate parietal isocortex. It is only weakly externopyramidal, externoteniate, and propebistriate. The already homotypical field shows an average pigmentation and myelin content. These structural features permit its classification as a belt area of the retrosplenial core.

Adult↗
PubMed1979

Pigment architecture of the human telencephalic cortex. V. Regio anterogenualis.

Cortical lamination and parcellation of the anterogenual region in the human brain is studied in sections successively stained for nerve cells (15 micrometers), myelin sheaths (100 micrometers), and lipofuscin granules (800 micrometers). The anterogenual region covers a crescent-shaped territory in front of the genu corporis callosi. It abuts on the allocortex, i.e., the supracallosal derivatives of the cornu ammonis and subiculum on the one side, and the mature frontal isocortex on the other side. The region is divisible into four areas. The transitory unitoteniate area ectogenualis is followed by anterogenual core fields, which show an outstandingly internopyramidal and internoteniate character. Furthermore, the core is of the infraradiate type and shows only the lower band of Baillarger. It is magnocellular, generally poor in myelinated fibres (typus pauper) and rich in pigment (typus obscurus). Minor structural differences permit the distinction of the area anterogenualis simplex from the area anterogenualis magnoganglionaris. Especially in the magnoganglionic field, layer Vb is richly endowed with a large, particularly slender and pigment-laden type of pyramidal cell. Within the proisocortex this special constituent occurs only in the anterogenual region. Structural features indicate its relationship to the Betz-pyramids of the cingulate and precentral ganglionic core fields. The transitory area paragenualis can be considered a belt-area accompanying the anterogenual core. It is weakly internopyramidal and internoteniate, thereby mediating to the surrounding frontal isocortex.

Cerebral Cortex↗
PubMed1978

Pigment architecture of the human telencephalic cortex. III. Regio praesubicularis.

Cortical lamination and parcellation of the human presubicular region is described with the aid of stereomicroscopical analysis of pigment preparations up to 1000 micrometers thick. The region can be subdivided into three major territories each of which is strongly influenced by the adjoining cortical tissue. The three subregions are: 1) the presubiculum sensu stricto. It lies near the subiculum at its medial margin and can be subdivided into 6 areas. 2) the parasubiculum. It borders on the entorhinal region and is composed of 5 areas. 3) the transsubiculum. It forms a transitional zone between allocortical and isocortical fields and consists of 3 areas. The presubicular region is characterized by a conspicuous layer of small and densely packed cells which--except the marginal parts of the subiculum--does not appear outside this region. Besides this autochthonous parvopyramidal layer, the presubicular cortex is composed of "foreign" cell layers which penetrate in varying number and to a varying extent into the region from the surrounding fields. The presubicular cortex shows extensive and incessant local variations, in so far as each one of its layers is very variable in breadth. In spite of this, a reliable parcellation can be achieved when only those layers are taken into consideration whose marginal parts are clearly recognizable. Hence, the proposed parcellation is based on the changing pattern of lamination which is depicted in diagrams for easy recognition of the various areas.

Adult↗
PubMed1978

Loss of pigment-laden stellate cells: a severe alteration of the isocortex in juvenile neuronal ceroid-lipofuscinosis.

Juvenile neuronal ceroid-lipofuscinosis is associated with a moderate numerical decrease of isocortical neurons. From Nissl preparations, it is not apparent, whether this neuronal rarefication occurs at random or affects specific types of cortical neurons. Lipopigment preparations facilitate the distinction between pyramidal and stellate cells. In juvenile neuronal ceroid-lipofuscinosis, they reveal an almost complete to total loss of small pigment-laden stellate cells. This type of local circuit neurons, scattered throughout the corpuscular and pyramidal layer in varying numbers and patterns of distribution, is common to all isocortical regions. Its pronounced and selective vulnerability in this lysosomal disease may be causally related to the marked functional impairment of the brain.

Adolescent↗
PubMed1978

On magnopyramidal temporal fields in the human brain - probable morphological counter parts of Wernicke's sensory speech region.

Posterior parts of the human superior temporal gyrus have been examined by means of stereomicroscopical observations of pigment preparations up to 800 microgram thick. As a rule, the proximal half of the first transverse gyrus of Heschl is covered by an extremely lightly pigmented conicortex which is surrounded by belt areas, a proncoinocortex anteriorly and paraconiocortical fields posteriorly and laterally. The paraconiocortex is divisble into a primitively organized part lying just behind the conicortical core and a more advanced portion forming the temporal magnopyramidal region. This extended lateralmost part of the paraconicortex is more or less richly endowed with unusually large and pigment-rich IIIc-pyramids. Third layer pyramidal cells showing densley aggregated lipofuscin deposits are rarely encountered within the human isocortex. As regards the temporal lobe, pyramids of this type, in general, do not occur outside the magnopyramidal region. The magnopyramidal region covers only a part of the temporal plane but extends much more in the lateral direction spreading over distal portions of the first and the second transverse gyri, posterior parts of the exposed surface of the superior temporal gyrus and those of its lower wall. The extension of the magnopyramidal region varies considerably from one side of the brain to the other. It is also subject to a pronounced variation from one individual to another. On account of its localization and its uniqueness in cortical structure, the temporal magnopyramidal region is considered to represent the morphological counterpart of the sensory speech centre of Wernicke.

Aged↗
PubMed1978

Simple and durable staining of thick sections of the human brain for macroscopic study.

Observations on gross morphology of the brain is greatly facilitated by enhancing the contrast between gray and white matter. The proposed technique is much more simple than the generally recommended Mulligan method and it variations. Moreover, there is no loss of stain since the fugitive surface impregnation, obtained by the Mulligan method, is replaced by a thoroughgoing block-staining procedure with the nonfading copper phathalocyanine dye astra blue. Staining procedure: wash formalin-fixed brain slices overnight in running tap water. Place slices in performic acid for 1 hour. Wash in running tap water. Place slices individually in staining solution consisting of 0.1 g astra blue (Merck) in 1000 cc distilled water and 1 cc HCl (37%), for 12-24 hours. Wash in running tap water. Embed in gelatin and mount in plastic cuvettes.

Brain↗
PubMed1978

[Brain warts].

26% of the brains studied (108) reveal warty extraversions which predominantly lie within the limits of the frontal lobe where they can be most frequently encountered on the lower frontal gyrus. Most of them occupy the crest of a gyrus. Only a few elongated ones can be found in the vicinity of the bottom of a sulcus. The various laminae of the cortex are subjected to variations. The molecular layer (I) contains a great number of ectopic nerve cells. Pigment-laden stellate cells and those devoid of pigment inclusions can be encountered besides a great number of various types of pyramidal cells. The nerve cells of the corpuscular layer (II) appear loosely arranged. The pyramidal layer (III) follows the curvature of the wart but appears attenuated towards its tip. Both the ganglionic layer and the multi-form layer show a lens-shaped thickening. If compared with an equal-sized part of the adjoining normal isocortex there is no numerical increase of nerve cells within the wart.

Astrocytes↗