Nuevas Tecnologías: Dispositivos móviles en el entorno sanitario / No disponible

Breve repaso sobre la tecnología en el entorno sanitario y los sistemas de información asistencial que, según algunos expertos, mejoran el cuidado del paciente (AU)

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Effects of chronic ethanol consumption beginning at adolescence: increased numbers of dendritic spines on cortical pyramidal cells in the adulthood.

To increase our understanding of the effects of chronic ethanol consumption beginning at adolescence, 25% ethanol in drinking water (v/v) was administered daily to young rats aged 45-50 days for 5 months. Increased numbers of dendritic spines on the apical dendrite of layer V pyramidal neurons of the somatosensory cortex (U-Mann-Whitney test, P less than 0.01-0.05) were found in almost every 50-micron-long segment over a distance of 500 microns from the cell body in ethanol-treated rats at the age of 195-200 days when compared with age-matched controls. Although the mechanisms leading to this unusual finding are not know, it is suggested that impairment of the naturally occurring elimination of redundant synapses can not be ruled out.

Decreased numbers of dendritic spines on cortical pyramidal neurons in dementia. A quantitative Golgi study on biopsy samples.

The number of dendritic spines on the apical dendrites of layer III pyramidal cells was counted in cerebral biopsies, processed in part according to the rapid Golgi method, which had been performed for diagnostic purposes on patients suffering from dementia of different origins. The samples were from cases affected by Alzheimer's disease (3 patients), Parkinson's disease and dementia (1 patient), Creutzfeldt-Jacob disease (4 patients), Pick's disease (1 patient) and dementia paralytica (1 patient). Spines were counted on consecutive segments of the apical dendrite along the 500-microns proximal region from the cell body. A significant decrease in the number of spines was observed in almost every segment of the apical dendrite in demented patients when compared with similar measurements carried out in age-matched controls (p less than 0.01-0.001); Mann-Whitney U-test. Decreased numbers of dendritic spines may result in reduced inputs on cortical neurons and may be a consistent morphological substrate for the impaired mental status in cortical dementia.

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.

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.

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.

Multiply resistant Haemophilus influenzae type b causing meningitis: comparative clinical and laboratory study.

Thirty-five patients with meningitis caused by Haemophilus influenzae type b were admitted to our hospital from January 1981 to December 1984; 60% of the strains were resistant to ampicillin, 65.7% to chloramphenicol, and 57% to both antibiotics. No significant differences in age, sex, previous treatment, clinical symptoms, outcome, and mortality were found between the 20 patients whose strains were resistant to both ampicillin and chloramphenicol and the other 15 patients whose strains were susceptible to ampicillin, chloramphenicol, or both. Alternative therapeutic agents were a combination of carbenicillin and gentamicin and new cephalosporins. At present, cefotaxime is our treatment of choice for meningitis caused by H. influenzae type b.

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.

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.

A Golgi study of cerebellar malformation in 13 trisomy.

The structure of cerebellar malformations in the brains of two infants with 13 trisomy has been studied by means of the Golgi method. Poorly organized cerebellar dysplasias (heterotaxias) are composed of Purkinje, Golgi and granule cells arranged and oriented in a disorderly fashion. The variable orientation and organization of the dendritic arbor of Purkinje cells within these cellular aggregates is supposed to be related to abnormal distribution of parallel fibers. Large ganglion cell heterotopias are not a homogeneous group, but two distinct types may be defined. First, Purkinje cell heterotopias which are located in the white matter of the cerebellum below the normally formed folia; these are composed of large neurons with arrested migration to the cortex. Secondly, multipolar cell heterotopias which are located in the deep white matter near the dentate and the roof nuclei, formed of neurons belonging to the deep cerebellar nuclei.

Effects of prenatal exposure to ethanol on the maturation of the pyramidal neurons in the cerebral cortex of the guinea-pig: a quantitative Golgi study.

The effects of chronic ethanol consumption during gestation on the development of layer V pyramidal cells was studied quantitatively in the somatosensory cerebral cortex of the newborn guinea-pig. The spread of the basilar dendritic arborizations and counts of dendritic spines on the apical dendrite of neurons that had been processed with the rapid Golgi method were compared with those found in age-matched controls receiving an isocaloric diet without alcohol. There were significant differences in the number of primary basilar dendrites (P less than 0.05) and dendritic ramifications at a distance of 25 micron from the soma (P less than 0.01) between the alcohol-exposed and control animals. There also were significant differences in the number of dendritic spines on the apical dendrite (P less than 0.001). This experimental model further illustrates developmental anomalies in the cerebral cortex following prenatal ethanol exposure.

A Golgi study of cerebellar atrophy in human chronic alcoholism.

When processed by the rapid Golgi method, a significant reduction (P less than 0.002) of the dendritic arborization of Purkinje cells located at the tips of the folia of the rostral vermis was demonstrated in four human cases of cerebellar atrophy, related to chronic alcohol consumption. Except for isolated damaged Purkinje cells located on the depth of the sulci of the rostral vermis in all but one case, no significant differences were observed between alcoholic cases and controls of comparable ages among Purkinje cells located in the remainder of the vermis or the cerebellar hemispheres. These results suggest that structural changes, which precede neuronal death and cell loss, are present in Purkinje cells of the rostral vermis in human cerebellar alcoholic degeneration.

Familial agenesis of the corpus callosum with hypothermia and apneic spells.

Two siblings, a boy and a girl, with agenesis of the corpus callosum, apneic spells, attacks of apnea, cyanosis and spontaneous hypothermia, are reported about. Both children died after a few months of life. Postmortem examination revealed a severe spongiosis of the white matter in addition to the agenesis of the corpus callosum and septum pellucidum, in both cases.

Tuberous sclerosis: a Golgi study of cortical tuber.

The cytoarchitecture and fine structure of seven cortical tubera were studied by means of camera lucida drawings and Golgi sections in the coronal, sagittal, and tangential planes. Varied structural disorganization was observed in different tubera. Cytoarchitectural study revealed the absence of laminar and columnar cortical organization, whereas Golgi's method showed abnormal neuronal orientation and distribution. Pyramidal neurons manifested malrotation and orientation of the apical dendrites in aberrant directions. Large numbers of stellate cells in addition to medium-sized and small pyramids predominated in the intermediate and deep regions of the tubera. A generalized but focally accentuated disorder of cell migration and neuronal organization is postulated.

The cerebral cortex of the new-born guinea pig. A quantitative Golgi study of the layer V pyramidal cell.

Quantitative studies have been performed in pyramidal cells (layer V) of the guinea pig's cerebral cortex when the animal were still-born and then not influenced by external sensorial stimuli nor by environment experience. Results related to basal ramifications of the pyramidal cells are similar to those reported in other species. Dendritic spines showed an increased in density along the length of the apical dendrites in a logarithmic regression. A similar pattern of distribution of dendritic spines along the apical dendrite was observed in a given animal, but interindividual variability was demonstrated.

Fine structure based on the Golgi method of the abnormal cortex and heterotopic nodules in pachygyria.

The structure of the four-layer abnormal cerebral cortex and of the heterotopic cerebral nodules in pachygyria has been studied by means of the Golgi method. The external cellular layer is formed by neurons closely mimicking, in morphology and distribution, those observed in layers V-VI of the normal cortex, although major abnormalities in orientation of pyramidal cells are a prominent abnormal feature. The internal cortical cellular layer is composed of several neuron types in which no distinctive layered organization can be detected. Heterotopic cerebral nodules are formed by neurons of the cortical types with random orientation of their cellular processes. Some extrinsic axons have been demonstrated, thus suggesting lack of isolation of heterotopic nodules.

[Hereditary neuropathies in childhood. Study of 31 patients]. / Neuropatías hereditarias en la infancia. Estudio de 31 pacientes.

Authors present the results of prospective clinical and electrophysiological study on 31 children diagnosed of inherited sensory-motor neuropathy. Patients were grouped according to their electrophysiological findings and their mode of inheritance, which was ascertained in all the cases by clinical and electrophysiological study of their parents. The large number of patients, felt into a group with identical characteristics of type I, HSMN of Dick and Lambert. A second group of patients, with a wide range of clinical manifestations, in some cases suggestive of type III HSMN, showed a sporadic mode of inheritance and evidence of demyelination on electrical studies. The third group of patients, which were classified as type II HSMN, showed again, a wide range of clinical manifestations, with some patients severely involved, and thus, casting some doubt on the benign prognosis of this type of neuropathy claimed by some authors.