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Biomedical subjects

I Ferrer

Publications and source records attributed to I Ferrer.

At least 343 records · Page 19Linked to original sources
PubMed1987

Primary degeneration of the granular layer of the cerebellum (Norman type). A Golgi study.

Purkinje cells, impregnated with the rapid Golgi method, in a patient with primary degeneration of the granular layer showed abnormal orientation of the perikaryon and dendrites, reduction in size of the dendritic arbor, absence of spiny branchlets, and large numbers of stubby spines and hypertrophic spines on secondary dendritic branches; stubby spines and thorn-like formations were seldom observed on the primary dendrites and perikaryon of some Purkinje cells. These findings are similar to those described in the cerebellum of the homozygous weaver mutant mouse and in the cerebella of experimentally induced agranular phenocopies, thus suggesting that similar plastic changes occur in human and animal Purkinje cells as a result of the absence of parallel fibres input in early developmental stages. In addition, Purkinje cells in this patient showed club-shaped deformities in the distal region of primary dendrites, which were filled with radially oriented, short dendrites covered with stubby spines and hypertrophic spines. These latter structures appear to be fully impregnated asteroid bodies observed in paraffin sections.

Adolescent↗
PubMed1987

Effects of prenatal ethanol exposure on dendritic spines of layer V pyramidal neurons in the somatosensory cortex of the rat.

The number of dendritic spines on consecutive segments from the cell body along the 400-600 micron proximal region of the apical dendrites of layer V pyramidal neurons, impregnated with the rapid Golgi method, in the somatosensory cortex was counted in ethanol-treated rats during gestation (25% ethanol in drinking water representing 30-35% of the total caloric intake) and in age-matched controls at postnatal ages 4, 15, 30 and 90 days. Although the mean values were lower in ethanol-treated rats than in controls during the first fortnight of postnatal life, significantly lower numbers of spines were observed only in the 15-day-old rat (Student's t-test, P less than 0.01-0.001). Spines with long, thin pedicles were characteristically encountered in ethanol-treated and controls aged 4 days; this sort of spine also predominated in ethanol-treated rats aged 15 days, but not in age-matched controls. The decrease in number and the abnormal morphology of spines was no longer present in ethanol-treated rats aged 30 and 90 days. These data suggest that impaired maturation of dendritic spines on cortical pyramidal cells, followed by recovery of the altered parameters at the end of the first postnatal month, occurs in the offspring of ethanol-treated rats during gestation.

Age Factors↗
PubMed1987

Dendritic spine anomalies in fetal alcohol syndrome.

Neuropathological findings in the brain of a 4-month-old child born to a chronic alcoholic mother were microcephaly, uncovered rostral region of the insula, disordered arrangement of nerve cells in the cerebral cortex, cerebellar abnormalities, and glial meningeal heterotopies. In addition, impregnantion of neurons by means of the Golgi method showed decreased numbers of dendritic spines and predominance of spines with long, thin pedicles on cortical pyramidal cells. A significant reduction in the number of DS (Student t test; p less than 0.001) on the apical dendrites of layer V pyramidal neurons was demonstrated in this patient when compared with similar counts performed in the brain of controls aged newborn, three months and four months. Reduced numbers of DS and abnormal geometry of spines observed in this child suggest that an abnormal maturation of nerve cells may occur in children, like it has also been demonstrated to occur in rodents, as a consequence of chronic ethanol consumption during gestation.

Brain↗
PubMed1987

Non-pyramidal neurons of layers I-III in the dog's cerebral cortex (parietal lobe). A Golgi survey.

In an attempt to classify neurons in the upper layers of the cerebral cortex according to modern nomenclature based on Golgi impregnations, non-pyramidal neurons in layers II and III of the dog's cerebral cortex have been categorized into thirteen types: large double-bouquet cells with long ascending and descending axons (type I double-bouquet cells); bipolar neurons; multipolar neurons with long tufted descending axons (type II double-bouquet cells); neurons with long ascending axons; neurons with superficial axon plexuses; elongated large multipolar neurons with extended generalized axonal arborizations; neurons with long descending axons; small bi-tufted neurons with short ascending, descending or local axons; small multipolar neurons with short ascending, descending or local axons; multipolar neurons with local or extended axonal arborizations usually forming arcades (some of them also with a long descending axon); basket cells; neurogliaform neurons, and chandelier cells. Neurons in the molecular layer were horizontal cells and multipolar neurons with short axons. These data have been compared with those described in other species to provide a provisional classification of non-pyramidal neurons located in the upper layers of the cerebral cortex.

Animals↗
PubMed1987

The basic structure of the neocortex in insectivorous bats (Miniopterus sthreibersi and Pipistrellus pipistrellus). A Golgi study.

A Golgi study of the neocortex of Miniopterus sthreibersi and Pipistrellus pipistrellus revealed the presence of pyramidal cells distributed in an orderly fashion and many types of local-circuit neurons including small, medium-size and large multipolar cells with smooth dendrites and generalized axonal arborizations, double-bouquet neurons, chandelier cells, spiny stellate cells in midlevel of the cortex, sparsely spined multipolar neurons with ascending axons and horizontal cells of layer VI. In addition, extraverted neurons of layer II widely branching into the molecular layer and giant multipolar cells with very long and smooth dendrites embracing the whole cortical thickness distinguished the organization of the neocortex in these primitive species.

Animals↗
PubMed1987

Effects of altered thyroid function on histamine levels and mast cell number in neonatal rat brain.

The effects of altered thyroid function on the levels of histamine, histidine decarboxylase activity and the number of mast cells were studied in the brain of 5-day-old rats. At this age both brain histamine levels and mast cells number are at a maximum. In addition the major portion of the amine is stored in mast cells and upon subcellular fractionation it sediments in the crude nuclear fraction (P1). Treatments with thyroid hormones or thyrotropic hormone up to 5 days of age leads to a decrease in the histamine levels and mast cells number in the brain, whereas administration of the antithyroid agent 6-n-propyl-2-thiouracil increases both parameters. All treatments affected only the histamine in the P1 fraction and failed to alter the levels of neuronal histamine which is located in the supernatant of P1 (S1). These facts suggest that in neonatal rat thyroid hormones could be involved in the regulation of the levels of brain histamine by regulating the number of brain mast cells.

Animals↗
PubMed1987

Development of dendritic spines in the Vth's layer pyramidal neurons of the rat's somatosensory cortex. A qualitative and quantitative study with the Golgi method.

Increases in the number of dendritic spines (DS) and modifications in the morphology of spines are observed through the maturation of pyramidal neurons in the somatosensory cortex of the rat. A two-fold increment in the number of spines occurs during days 15 to 30, but a 20% reduction in the overall number of DS is observed between days 30 and 90 to reach the stabilized values in the rat aged 6 months. The representation in a graph of the distribution of spines along the apical dendrite is adjusted to a curve with the maximal score lying at a distance of 200-300 microns from the cellular body. Beyond this region the number of spines decreases following a gentle descending profile. In addition, modifications in the morphology of DS occur through the development. Mushroom-shaped, stubby and short, thin spines in the 30-day-old rat replace spines with long, thin pedicles characteristic of the early developmental stages. Both variability in the density of DS and individual variability with regard to the percentage of the different types of spines on the apical dendrites are observed among neurons in the same animal even in rats 90 days old and in rats aged 6 months.

Animals↗
PubMed1987

[Machado-Joseph disease in a family of Spanish origin].

The clinical observations in five patients, of a family of catalan origin (NE of Spain), affected with Machado-Joseph disease are reported. The pedigree showed the presence of 22 members affected (15 men, 7 women) over six generations. The symptoms and signs were variable among the patients and also variable in a same patient during the course of the disease. However, the main neurological alterations were ataxia, akinesia, distal amyotrophy, progressive external ophthalmoplegia, facial and lingual fasciculations and bulging eyes. The neuropathological examination performed in one patient disclosed degeneration of the posterior and spinocerebellar tracts in the spinal cord, marked nerve cell loss in Clarke's column and anterior horns and axonal degeneration of the peripheral nerves, in addition to nerve cell loss in the nuclei of the III, IV and VII cranial nerves and neuronal depletion in the substantia nigra. No other structures, including the striate complex and dentate nucleus, were significantly affected.

Aged↗
PubMed1987

A Golgi study of the sixth layer of the cerebral cortex. III. Neuronal changes during normal and abnormal cortical folding.

During normal development in the cat Layer VI cortical neurons, including pyramidal cells, fusiform neurons, inverted pyramidal cells and bipolar neurons located in the gyral regions retain the vertical orientation characteristic of earlier developmental stages. However, Layer VI pyramidal neurons and the subtypes in the sulcal zones develop long horizontal basilar dendrites which seem to form dendritic bundles with those of neighbouring pyramidal cells; in addition, fusiform neurons and bipolar cells are tangentially orientated and horizontal pyramidal neurons appear in place of inverted pyramidal cells in the gyral and intermediate regions. In human cortical malformations, neurons of the external cellular layer (Layers V and VI) in lissencephaly are vertically arranged, but Layer VI neurons in polymicrogyria are tangentially orientated when located in microsulci. These features suggest that neuronal changes occur in Layer VI neurons as a consequence of cortical folding and that cortical folding determines the cellular shape of Layer VI neurons in normal as well as in abnormal development of the cerebral cortex.

Animals↗
PubMed1986

Decreased numbers of dendritic spines on cortical pyramidal neurons in human chronic alcoholism.

Samples of the cerebral cortex (left hemisphere, area 6) were collected at autopsy, between 4 and 6 h after death in order to avoid artifacts related to fixation delay, from 5 chronic alcoholic patients (in which well-defined alcoholic-malnutritional encephalopathies were excluded) and 16 controls; samples were immediately processed according to the rapid Golgi method. The curves representing the average density of dendritic spines on the apical dendrites of layer V pyramidal neurons as a function of the distance from the cell body were adjusted to a logarithmical model which was shown to be similar in controls and alcoholic groups. Significant reduced numbers of dendritic spines were observed; however, in the alcoholic patients when compared to age-matched controls (P less than 0.001; Kruskall-Wallis chi 2 test). These results demonstrate noxious effects of ethanol on cortical pyramidal neurons in human chronic alcoholism.

Aged↗
PubMed1986

Structure of an isolated cerebellum and related nuclei developed within the matrix of a mature ovarian teratoma.

The distribution and organization of nerve cells in a microcerebellum and cerebellar stalk, developed within the matrix of a mature ovarian teratoma, were analyzed with respect to recent data on cerebellar histogenesis. It is postulated that a neuroectodermal germinal locus with proliferation capability similar to that found in the alar plates of the normal embryonic rhombencephalon was responsible for the formation of this highly organized neural tissue.

Adult↗
PubMed1986

A Golgi study of the polymicrogyric cortex in Aicardi syndrome.

The neuropathological examination of the brain of a 4-month-old girl with Aicardi syndrome (infantile spasms, chorioretinal lacunae, psychomotor retardation, agenesis of the corpus callosum and vertebral anomalies) showed agenesis of the corpus callosum, agenesis of the anterior commissure and abnormal orientation of the hippocampal formation, in addition to periventricular cerebral nodules and extensive non-laminated cortical polymicrogyria of the fronto-parietal regions and gyrus cinguli of both hemispheres. A non-communicating medial supracollicular cyst, racemose cysts of the choroid plexus, underdevelopment of the inferior cerebellar vermis tonsils were also observed. The study of the polymicrogyric cortex with the Golgi method revealed an abnormal orientation of neurons; but the different varieties of cells were located at the depth corresponding to that were they are normally found. The Golgy study of the periventricular nodules disclosed the presence of different types of cortex-like neurons. On the basis of these data it may be suggested that polymicrogyria is not a migratory disturbance, but rather the result of a partial necrosis of the cortical mantle occurring before the 5th month of foetal life.

Agenesis of Corpus Callosum↗
PubMed1986

Golgi study of the isocortex in an insectivore: the common European mole (Talpa europaea).

In the common European mole (Talpa europaea) the isocortex is a six-layered structure representing about 50% of the total cerebral cortex. The internal granular layer is narrow in the occipital region, however, probably reflecting a poorly developed visual system in an animal adapted to life in a subterranean environment. Golgi impregnation of projection cells and most local-circuit neurons of layers III-VI suggests a relatively well-developed isocortex in this insectivore. The presence of extraverted neurons in the so-called accentuated layer II and the amount of local-circuit neurons with very long beaded dendrites, however, probably represents primitive characteristics of the isocortex in mammals.

Animals↗
PubMed1986

A Golgi study of the sixth layer of the cerebral cortex. I. The lissencephalic brain of Rodentia, Lagomorpha, Insectivora and Chiroptera.

A study of the morphological characteristics of the neurons in layer VI of the cerebral cortex was carried out using the rapid Golgi method in several lissencephalic species including Rodentia (rat, mouse, vole (Microtus agrestis) and hamster), Lagomorpha (rabbit), Insectivora (hedgehog) and in the Chiroptera the dwarf bat (Pipistrellus pipistrellus). There was a basic uniformity in the structure of the sixth layer. Main neuronal types in lamina VIa were large pyramidal neurons, triangular or atypical pyramidal cells, multiapical pyramidal neurons, inverted pyramids, fusiform neurons, Martinotti cells and bi-tufted cells. Main neuronal types in lamina VIb were medium sized, flattened pyramids, large and small horizontal neurons, horizontal pyramidal cells, fan shaped neurons and multipolar spinous neurons with long descending axons. Sparsely spinous and spine-free multipolar neurons with short axons were present in the two laminae of layer VI, but sparsely spinous neurons with axons similar to those found in basket cells of other layers of the cortex were observed mainly in lamina VIa. Neuronal subsystems were tentatively classified on the basis of the course of the axons. Pyramidal neurons, fusiform neurons, multiapical pyramidal cells, inverted pyramidal cells, fan shaped neurons and multipolar neurons with large descending axons were interpreted as being the main source of long projection and association connections. Large horizontal neurons were interpreted as possible ipsilateral association neurons because the horizontal course of the axons over long distances followed the boundary of the deeper region of the sixth layer. Three intracortical (association) subsystems were included. Axons of Martinotti cells and collateral ascending axons of pyramidal neurons (including multiapical pyramidal neurons) formed the ascending interlaminar fibrillary subsystem. Axons of small horizontal cells and horizontal collaterals of pyramidal neurons formed the horizontal intracortical subsystem. Sparsely spinous and spine-free multipolar neurons and bi-tufted cells were the main source of the local, non-horizontal fibrillary subsystem.

Anatomy, Comparative↗
PubMed1986

A Golgi study of the sixth layer of the cerebral cortex. II. The gyrencephalic brain of Carnivora, Artiodactyla and Primates.

The sixth layer of the cerebral cortex has been studied by means of the Golgi method in Carnivora (dog and cat), Artiodactyla (cow and sheep), and Primates (human) brains; a basic structural uniformity being observed in all these species. Projection neurons of lamina VIa were large and medium sized pyramidal neurons (including atypical and multiapical), small pyramidal cells, and spinous multipolar neurons with long descending axons. Projection neurons of lamina VIb were medium sized pyramidal neurons and small pyramids, horizontal pyramids, inverted pyramidal cells, spinous multipolar neurons with long descending axons and large fusiform cells. Local circuit neurons of lamina VIa were Martinotti cells, basket neurons, neurogliaform cells, sparsely spinous neurons with whirled axons, spine-free multipolar cells and bipolar neurons. Local circuit neurons of lamina VIb were sparsely spinous and spine-free multipolar cells with short axons and bipolar neurons. Marked differences were observed between gyral, intermediate and fissural regions. Fusiform and bipolar neurons were vertically arranged in the former, but were tangentially orientated in intermediate and fissural regions; inverted pyramidal cells were present in the gyrus but horizontal pyramids were the respective cells in the intermediate and fissural zones. When compared with lissencephalic species, a great horizontal fibrillary system (which is vertically arranged in gyral regions) was observed in convoluted brains. Cells of origin were fusiform neurons, bipolar cells, horizontal and inverted pyramids and pyramidal neurons (the latter by means of horizontal axonal collaterals). The great development of this cortico-cortical association system in gyrencephalic species is considered to be a major step in neocortical evolution.

Animals↗