Biomedical subjects

J Dziewiatkowski

Publications and source records attributed to J Dziewiatkowski.

At least 37 records · Page 2Linked to original sources

PubMed2000

Developmental changes of MAP2 immunoreactivity in the hippocampus proper and dentate gyrus of the rat.

Microtubules are present in high concentration in the nervous system and are a prominent component of the neuronal cytoskeleton. Microtubules are composed of tubulin and variety of microtubule-associated proteins (MAPs), which have been implicated in the regulation of microtubule assembly and function. MAP2 is the most abundant of these proteins, and it has been extensively characterized in various functional and pathological conditions. In the present study the distribution of MAP2 was examined in each layer of the CA1 and CA3 regions of the hippocampus proper and dentate gyrus in rat development. A total of 40 brains at various ages starting from postnatal day (P) 0 to P90 were examined. After perfusional fixation the brains were frozen and cut on the coronal plane and stained with either cresyl violet or standard immunohistochemical methods using the anti-MAP2 antibody. MAP2 exhibited a somatodendritic pattern of localization in cells of the hippocampus. Staining was most prominent in dendrites and perikarya as well as granules surrounding cell bodies. In a newborn rat's brain immunostaining was intense in granules and faint in perikarya. Between P4 and P21 immunostaining density for MAP2 was stronger and appeared in perikarya, granules, and dendritic trees. After P21 the perikarya and dendrites of the pyramidal layer and stratum radiatum of the hippocampus proper, as well as the molecular and granular layer of dentate gyrus, showed reduced immunoreactivity. In the stratum oriens of the hippocampus and polymorphic layer of the dentate gyrus immunoreactivity was still strong until P90.

Age Factors↗

PubMed2000

The influence of the intraventricular hemorrhage on the intracranial pressure and hemodynamic changes in the experimental intracerebral hemorrhage in the rabbits.

The experimental model of the intracerebral hematoma in the rabbit was used for the investigation of the changes of the intracranial pressure and selected hemodynamic parameters. The study was performed on 13 adult rabbits, divided into two groups receiving 1 ml (group I--6 animals) and 2 ml (group II--7 animals) of fresh arterial blood, respectively. The monitoring of the intracranial pressure (ICP), the mean arterial blood pressure (MABP), the heart rate (HR), the end-tidal CO2 concentration (ETCO2) and the body temperature was measured every minute in the hematoma production phase and every 5 minutes for the consecutive three hours. The volume of the hematoma was calculated according to Cavalieri formula, with the use of the system for the automatic picture analysis. The mean volume of the intraparenchymal part of the hematoma in group I was higher than in the group II. However, in all the representatives of the second group the evidence of the intraventricular hemorrhage was present. The dynamics of the ICP, MABP and HR changes differed significantly in both groups during the period of the observation. On the basis of the physiological and morphological observations we conclude that the changes of ICP remain the most sensitive and valuable parameter during the early course of the intracerebral hemorrhage. Coexistence of the rapid ICP, MABP and HR changes must be always regarded as the possible sign of the intraventricular hemorrhage.

Animals↗

PubMed2000

Substance-P of neural cells in human trigeminal ganglion.

Expression of substance-P in human neurons of trigeminal ganglia has been investigated by immunohistochemistry and morphometry. These neurons constituted 12.8% to 32.6% of the total neuronal population in the trigeminal ganglia. Substance-P positive granulations were concentrated around the nucleus, distributed focally in neuroplasm or dispersed over the neuroplasm. Morphometric analysis has indicated the presence of three populations of SP-positive cells: small, medium-sized and large. The results suggest a functional differentiation on the level of the first neurons of the afferent path of the stomatognathic system. Substance-P is likely to play a role in the transmission not only of nociceptive impulses but also of those involved in the mechano-functional stimulation of system activities.

Adult↗

PubMed1999

Cerebellar atrophy in Alzheimer's disease-clinicopathological correlations.

Morphometry of the cerebellum of 11 subjects who died in the severe, final stage of Alzheimer's disease (AD) and of five age-matched subjects without dementia revealed significant atrophy in the AD group, with a decrease in the volume of the molecular layer by 24% and of the granular layer by 22% in comparison with controls. The 32% decrease in the total number of Purkinje cells that was observed correlates with the atrophy of the molecular layer, whereas the 30% reduction in the total number of granule cells correlates with the atrophy of the molecular and granular layers. A unique pattern of Alzheimer-type pathology was observed in the cerebellum: (1) there were no neurofibrillary changes in the cerebellum of either the control or the AD subjects, (2) there was almost the same extent of leptomeningeal and cortical amyloid angiopathy in the normal aged subjects and in the AD patients, and (3) the presence of plaques was noted in the AD group, but not in the control group. This pattern of pathology suggests that two factors might be considered in the etiopathogenesis of cerebellar atrophy: (1) transneuronal degeneration and neuronal loss resulting from primary pathologic changes in cerebral structures and (2) parenchymal cerebellar ss-amyloidosis. The correlation between the temporal duration of AD and both the decrease of the total number of granule cells (r=0.86, p<0.01) and the volumetric loss of the molecular (r=0.73, p<0.05) and granular (r=0.93, p<0.001) layers of the cerebellar cortex indicates that these cerebellar atrophic changes are likely to be related to the basic pathologic process of AD. Similarly, the correlation between the most complex parameter the atrophy of the cerebellar cortex and the Functional Assessment Staging (FAST) measure of the clinical severity of AD at the time of demise (r=0.63, p<0.05) as well as with the duration of AD (r=0.78, p<0.01) indicates that cerebellar pathology, when viewed holistically, evolves continuously in association with clinical changes throughout the clinically manifest course of AD.

Aged↗

PubMed1999

The developmental changes of the "paraclaustral reservoir" of migrating cells in the rat brain: a study using morphometric and in situ DNA end labeling techniques.

A distinct group of small cells lying in the ventral part of the external capsule in the rat brain is clearly visible at birth. On the basis of its location (medially to the prepiriform claustrum) and probably its function (as a source of neurons for adjacent structures), we define this nucleus as the "paraclaustral reservoir". The present study reveals the cellular changes of the paraclaustral reservoir during postnatal development of the rat brain using unbiased morphometry and in situ DNA end labeling. During the first 4 days after birth the density and total number of cells in the paraclaustral reservoir were stable; after this period a decrease of these parameters was observed until the complete disappearance of this structure at the end of first postnatal week. The rather low number of TUNEL (TdT mediated dUTP nick end labeling of fragmented DNA) positive nuclei in the paraclaustral reservoir suggests that apoptosis is not a crucial mechanism leading to decay of this structure.

Aging↗

PubMed1999

Comparative anatomy of the claustrum in selected species: A morphometric analysis.

The morphology of the claustrum was studied by stereological methods in representatives of five mammalian orders (Insectivora, Rodentia, Lagomorpha, Carnivora and Primates). In each species under study, a dorsal and a ventral part of the nucleus can be distinguished. Based on differences in shape and separation from surrounding structures, five morphological types of the claustrum occur. The claustrum of Insectivora and some rodents represents the least complicated morphological type. The nucleus is very poorly separated from the surrounding structures. The human claustrum is morphologically the most complicated, although the two above-mentioned principal divisions are apparent. The ventrally situated paraamygdalar part of the human claustrum may correspond to the endopiriform nucleus or ventral part of the claustrum of other mammals, because of its morphological characteristics and connections with the limbic system. In guinea pigs, traditionally classified as members of the Rodentia, a characteristic morphological type of the claustrum is present. This observation may support arguments questioning the current position of this species in mammalian classification. Based on stereological studies, the increase of the claustral volume that occurs with increase of the hemispheric volume is significantly smaller than the increase of the isocortical volume and larger than the increase of the allocortical volume. The increase of the volume of the dorsal and ventral parts of the claustrum does not differ significantly in the species under study. Neurons of the claustrum represent differentiated morphology. The numerical density of neurons in the dorsal part of the claustrum is significantly higher than in the ventral one. Differences in the morphology and cellular structure of the two parts of the claustrum may suggest differences in function of the two parts of the nucleus, most probably concerned with transfer of information among various cortical regions. Changes in the claustrum, a cortico-related structure, that occur with increased brain volume, may suggest that its development is less dynamic than that of the isocortex.

Animals↗

PubMed1999

The shape of the inferior horn of the lateral ventricle in relation to collateral and occipitotemporal sulci.

The shape of the inferior horn of the lateral ventricle has been investigated in 100 (50 right and 50 left) human brain hemispheres which were fixed in 40% formaldehyde solution and cut frontally. It has been found that the shape of the inferior horn depends on the course and depth of the collateral and occipitotemporal sulci. In most cases a part from two main ventricular surfaces: the hippocampal and superolateral, there is one surface more, either the inferior-collateral eminence (Type I--97% of cases in the posterior part of the inferior horn, 49%--in the middle and 42%--in the anterior part) or the inferolateral, adjecent to the occipitotemporal sulcus (Type II--0%, 26% and 35%, respectively). In a few cases both collateral eminence and inferolateral surface were present (Type III--3%, 2% and 6% respectively). In type IV neither collateral eminence nor the inferolateral surface appeared (0%, 23%, 17% respectively). The authors suggest to designate the inferolateral surface, not mentioned in the literature, as the occpitotemporal eminence (of the inferior horn).

Adult↗

PubMed1998

Reduced number and altered morphology of microglial cells in colony stimulating factor-1-deficient osteopetrotic op/op mice.

The numerical density of microglial cells is reduced by 47% in the corpus callosum, by 37% in the parietal cortex and by 34% in the frontal cortex of mice mutant at the op locus which are totally devoid of colony stimulating factor-1 (CSF-1), the major growth factor for macrophages. Moreover, microglia in the frontal cortex of the op/op mice are smaller and have shorter cytoplasmic processes compared to control mice. Study suggests that CSF-1 plays a role in vivo in the formation and maturation of microglia and has little or no effect on perivascular cells.

Animals↗

PubMed1998

The cortico-related zones of the rabbit claustrum-study of the claustrocortical connections based on the retrograde axonal transport of fluorescent tracers.

The claustrocortical connections in the rabbit were assessed for the first time by the method of axonal retrograde transport of two fluorescent tracers (Fast Blue and Diamidino Yellow). The material consisted of 23 adult New Zealand rabbits. Projection zones of spindle-like form, connected with the precentral, postcentral, temporal and occipital cortices have been delineated. They are organized topographically both in the anteroposterior and ventrodorsal direction. The precentral (motor) projection zone is localized in the anterodorsal part of the claustrum. It may be divided into two separate parts that project to the medial and lateral part of the precentral cortex. The large postcentral (somatosensory) zone occupies mainly the central part, whereas the temporal (auditory) and occipital (visual) zones are situated in the posteroventral part of the claustrum. The overlap of various claustral projection zones is differentiated, the largest being that of the somatosensory zones. In comparison to the results of study of claustral projection zones performed on other species, presumably on the rat and cat, its seems plausible to conclude that the extension of claustral projection zones and degree of their overlap in the rabbit represent an intermediate character.

Animals↗

PubMed1998

Ultrastructural organization of the visual zone in the claustrum of the cat.

Data obtained by using ultrastructural and morphometric approaches revealed three types of neurons in the cat visual claustrum. The most numerous were medium-sized and large ones. They formed 3/4 of the cell population. The ultrastructural properties of those cell types were largely similar. Their cell bodies were oval, round, fusiform or triangular and contained more or less indented nuclear envelope. The cytoplasm of those cells was characterized by a high concentration of subcellular organelles and particularly rough endoplasmic reticulum. The characteristic feature of those cells was a low nucleus/cell body area ratio (47 +/- 1% and 43 +/- 1%, respectively). The proximal dendrites of medium-sized cells were usually wide at the base, relatively short and tapering, whereas, those arising in the large cells were often thick and had a short tapering base. The neurons described above stained by Golgi impregnation method showed spines on their distal dendrites both under the light and electron microscopy. The retrograde axonal transport of HRP and WGA-HRP following injections into the visual cortex confirm that they are mainly projection cells which form the ascending limb of the claustrocortical loop. The third type of neurons formed a less numerous group of small cells which differed from the larger ones in various respects. They possessed the large nuclei with deeply indented nuclear envelope and comparatively a thim layer of cytoplasm poor in subcellular organells among which free ribosomes and mitochondria were common. The nucleus/cells body area ratio high (59 +/- 2%). In Golgi preparations their dendrites did not show spines. The dendrites originating from that type of neurons were thin, long and did not posses a wide tapering base. They are mainly claustral intrinsic neurons.

Animals↗

PubMed1998

The projection of the amygdaloid nuclei to various areas of the limbic cortex in the rat.

The connections of the amygdaloid body with the areas of the limbic cortex in the rat were studied by means of the method on the axonal retrograde transport of the fluorescent tracer FluoroGold. The tracer was injected into the anterior and posterior limbic cortices (cingulate gyrus, granular and agranular retrosplenial area, respectively. The localization of the corresponding amygdalar projection zones was investigated and the semiquantitative analysis of the connections was conducted. The projection zones in the rat amygdaloid body are organized topographically. Administration of the fluorescent tracer to the anterior and posterior part of the limbic cortex in the rat (cingulate gyrus and both retrosplenial areas, respectively) reveals labeling of cells only for injections to the former one. The labeled cells were present only in the major components of the basolateral amygdaloid complex. The main source of this projection was anterior part of basolateral nucleus (BLA). Some labeled neurons were found in the lateral nucleus and few in the ventral part of basolateral nucleus. No labeled cells were found within the basomedial nucleus.

Amygdala↗

PubMed1998

Parvalbumin immunoreactivity changes in the thalamic reticular nucleus during the maturation of the rat's brain.

The thalamic reticular nucleus (Rt) is a thin lamina of cells, through which thalamocortical and corticothalamic fibers pass. It is interposed between the thalamic nuclei and the internal capsule and it is composed of GABA-ergic cells with synapses that receive impulses from both kinds of fibers. Rt takes part in the negative feed-back system of controlling the information transfer from the thalamus to the cerebral cortex and it is focused in the sleep-waking cycle. The pattern of parvalbumin reactivity during maturation of Rt becomes the main aim of our study. The study was performed on 36 rats on various postnatal days (P0, P1, P2, P4, P5, P7, P10, P14, P17, P21, P30 and P90). The animals were anesthetized, transcardially perfused, cut on cryostat into 30-microns-thick frontal sections, stained immunocytochemically using standard ABC method and a mouse monoclonal antibody against parvalbumin. A small amount of round and oval, parvalbumin immunopositive cells was detected at stage PO, predominantly in the intermediate part of Rt, whereas the cells in ventral and lateral part at the same time were only slightly immunopositive. At P10 the cells in the intermediate part became more fusiform or oval because of the appearance of dendrites. At P14 we were able to observe separate, punctuated structures interpreted as the axonal endings. There were plenty of them at the time of full maturation of the intermediate portion of reticular nucleus (stage P21). At this time, the dorsal and ventral parts had their first synapses, too, but their maturation ended a week later. At P30 multipolar neurons, with round and fusiform somata were distributed relatively homogeneously throughout Rt. We compared the stage with the parvalbumin reactivity of the adult rat and found no difference in the morphological pattern of PV neurons.

Animals↗

PubMed1998

The pattern of synaptophysin changes during the maturation of the amygdaloid body and hippocampal hilus in the rat.

Synaptophysin is an integral membrane protein associated with small, electron-lucent synaptic vesicles. Immunohistochemistry for this protein is a sensitive method to study subtle changes in synaptic density and distribution in various brain regions. In the present study, the synaptogenesis was examined in the rat basolateral amygdala in comparison with the hippocampal hilus, from the day of birth to adulthood. A total of 41 brains at various ages starting from P0 to P90 (P--postnatal day) were examined. After perfusional fixation the brains were frozen and cut in the coronal plane and stained either with cresyl violet or standard immunohistochemical methods using the anti-synaptophysin antibody. Synaptophysin positive granules appeared just after birth in both structures, but their number was very low (about 0.28 x 10(6) and 0.13 x 10(6) per mm3 in the amygdala and hippocampus, respectively). In the basolateral amygdala the number of synapses increased rapidly reaching the maximum at P14 (1.6 x 10(6) per mm3) followed by about 45% decrease in number up to P30 and later being stabile. In the hippocampus two increases of the synaptogenesis were observed. The first at P7 (about 1.7 x 10(6) of synapses per 1 mm3) which was followed by dramatic decrease up to 0.7 x 10(6) per mm3 at P14. The second increase appeared later (about P90) and reached 1.7 x 10(6) per mm3. After that time the density of synapses was stabile. It may be supposed that the first characteristic wave of synaptogenesis observed in the hippocampus and amygdaloid body is due to the overproduction of synapses observed at that time in other cortical regions. The late wave of synaptogenesis found in the hippocampus is related to the great plasticity of the interneuronal connections in this period of development.

Amygdala↗

PubMed1998

The corticoclaustral connections in the rat studied by means of the fluorescent retrograde axonal transport method.

The corticoclaustral connections in the rat were investigated by means of the method of the retrograde axonal transport of the fluorescent tracer (Fluoro-Gold; FG). The material consisted of 20 adult Wistar rats. The fluorescent tracer was injected into the anterior, middle or posterior parts of the claustrum. The retrogradely labeled neurons were detected in the layer VI of the neocortex. Injections of the tracer into the anterior part of the claustrum resulted in labeling of the neurons in the motor cortex. After administration of the tracer into the middle part of the insular claustrum, labeled neurons were present both in the motor and somatosensory cortices, while the injections of the tracer into its posterior part resulted in labeling of neurons in the visual cortex. Administration of the fluorescent tracer into the insular claustrum of the rat resulted in labeling of the cortical neurons of the corresponding areas of both hemispheres, however, the contralateral projections seem to be less numerous than the ipsilateral. Our results confirm the existence of reciprocal connections of the claustrum with the neocortex and suggest its role in integration and modification of information reaching the neocortex.

Animals↗

PubMed1998

The amygdaloid body of the rabbit--a morphometric study using image analyser.

The amygdaloid body is a telencephalic structure belonging to the limbic system. The amygdaloid body consists of the two main nuclear groups: corticomedial and basolateral. The former-phylogenetically older group is composed of the central, medial, and cortical nuclei, while the latter, phylogenetically younger one, of the lateral, basolateral and basomedial ones. The results presented in our paper indicate differences in the structure and topography of the specific amygdaloid nuclei. Their subdivisions in the rabbit are not as evident as in the rat. Apart from structural differences, the cellular composition of specific nuclei does not differ distinctly. It can suggest that their intrinsic and extrinsic connections might be similar and the role and function of them is maintained (with few exceptions) through the phylogeny.

Amygdala↗

PubMed1997

Volume and topographical changes of the basolateral complex during the development of the rat's amygdaloid body.

Volume and topography of basolateral complex during development and maturation in fetal and postnatal rat brains were studied using morphometrical methods. 39 rat brains of various ages were fixed in formalin, frozen and cut into 25-micron-thick sections and stained with cresyl violet. In cresyl violet preparation the basolateral complex appeared first on 17th prenatal day and it was composed of two homogenous parts--lateral and basolateral nuclei. On about 7th postnatal day each of these nuclei divided into two parts--the first one into the dorsolateral and ventromedial part, while the second one--into the anterior and posterior parts. Morphometric investigations showed that volume of the basolateral complex and its parts underwent the biggest changes up to 14th postnatal day, and we suspected that during this time it was more sensitive to pathological changes. After that day the volume of the basolateral complex had changed only a little.

Amygdala↗

PubMed1996

Subpopulation of dogs with severe brain parenchymal beta amyloidosis distinguished with cluster analysis.

A study of the brains of 30 dogs, mongrels from 6.5 to 26.5 years of age, revealed that all dogs older than 13 years of age develop amyloid-beta-positive plaques. Cluster analysis based on the age of the dogs and the numerical density of amyloid-positive plaques stained with monoclonal antibody 4G8 (17-24aa) revealed that the population of old dogs consists of two subpopulations: one with a very low (0.8/mm2 on average) and other with a high (19.2/mm2 on average) numerical density of plaques. These two groups (19.5 and 19.1 years of age, respectively) appear to emerge from the younger group (12.2 years of age on average), with moderate (2.2/mm2 on average) numerical density of 4G8-positive plaques. These data may indicate that only a portion of the mongrel population (43%) is susceptible to amyloidosis beta or that only this severely affected subpopulation was exposed to a factor or factors inducing this pathology and developed severe cortical amyloidosis that correlates with age. Dog plaques are only of the diffuse type, with nonfibrillar, thioflavin S-, and Congo red-negative amyloid in all groups distinguished by cluster analysis. Only from 10% of 4G8-positive plaques in the mildly affected group to 29% in the severely and 37% in the moderately affected group are Bielschowsky positive. In the younger, moderately affected group, 6E10 (1-17aa)-positive plaques prevail. In the two old groups with severe and weak changes, almost all 4G8-positive plaques are also 6E10-positive. Carboxy-terminal region immunocytochemistry reveals that BC42-positive plaques are numerous, whereas BC40-positive plaques are few or absent. The differences in the silver-positivity of plaques and their immunoreactivity in both the amino- and carboxy-terminal regions may reflect differences in amyloid-beta deposition and resolution. Dog parenchymal amyloidosis beta appears to be a model for the study of diffuse plaques.

Amyloid beta-Peptides↗

PubMed1996

Loss of neurons in the claustrum of aging brain.

The study was performed on 19 brains of nondemented patients with age ranging from 36 to 89 years. After embedding in paraffin, coronal 8-microns-thick serial sections were cut and stained either with cresyl violet or with immunocytochemical methods for amyloid and tangles. Morphometrical studies were performed in all parts of the claustrum along its whole extension. Changes related to aging (neuronal loss and decrease in volume) were found in all parts of the claustrum, but the time of origin of these changes is different in various parts of this structure. We did not observe neurofibrillary pathology in any parts of the claustrum. In the oldest subjects a small number of amyloid plaques was found in the paraamygdalar part of the claustrum. We suggest that the neurons of the claustroneocortical loop are affected severely and earlier than those in the claustroentorhinal loop.

Adult↗