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1
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Experience-dependent changes in vibrissae evoked responses in the rodent barrel cortex

100%
Glazewski S.
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vol. 58
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issue 4
309-320
EN
A change in vibrissae complement in rodents leads to long-term changes in vibrissae dominance. These changes involve both potentiation of spared vibrissae responses and suppression of deprived vibrissae responses in adolescent animals. In adult animals only potentiation of spared vibrissae responses was detected. Suppression exhibits hetero- and homosynaptic components and appears to be cortical in origin, as is potentiation. The time course for potentiation and suppression in the barrel cortex of adolescent rats is different, with suppression preceeding potentiation by at least one week. There seems to be no critical period for potentiation in superficial layers of barrel cortex, but there is a critical period for suppression. Suppression cannot be evoked if plasticity is induced later than at 6 months of age nor maintained if experimental manipulations begin later than at three months. The molecular mechanisms that underlie plastic changes in the barrel cortex still remain unclear, although a-CamKII and to lesser extend a/b-CREB appear to be involved.
2
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Molecular maps of neural activity and quiescence

80%
Chaudhuri A., Zangenehpour S., Rahbar-Dehgan F., Ye F.
Acta Neurobiologiae Experimentalis
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2000
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vol. 60
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issue 3
403-410
EN
The rapid accumulation of inducible transcription factors (ITFs), such as c-Fos and Zif268, in activated neurons combined with histological methods that offer detection at the cellular level are key features that have led to their wide use in visualizing activated neurons. There are two major drawbacks of ITFs that limit their use in the CNS - cell-type expression specificity and stimulus-transcription coupling uncertainty. Recent technical advances in the field of molecular activity mapping now permit dual-labeling approaches that help resolve some of these ambiguities and identify neurons that are activated by different sensory stimuli. Furthermore, the recent identification of the robl/LC7-like gene, which shows immediate-early repression after stimulation, may have utility in functional mapping where it can be used to delineate quiescent neurons and serve as a complement to molecular activity markers.
3
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Development and plasticity of the retina in the opossum Monodelphis domestica

80%
Djavadian R., Bisti S., Maccarone R., Bartkowska K., Turlejski K.
Acta Neurobiologiae Experimentalis
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2006
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vol. 66
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issue 3
178-188
EN
We investigated the rate of cell proliferation and death in the retina of the Monodelphis opossum during its postnatal development and the influence of early monocular enucleation on these processes. Our results show that in the opossum, as in other marsupials, the peak of the retinal cells divisions occurs postnatally and that generation of retinal cells continues till the time of eye opening (P34), except of the marginal rim, where it continued till P60. Ganglion and amacrine cells are generated between postnatal days (P) P4 and P9, while bipolar cells and photoreceptors are generated simultaneously between P14 and P25. The peak of ganglion cell death as detected by the TUNEL method occurs around P14?19 in the center of retina. The second peak of apoptosis appears in the inner nuclear layer (INL) at P19?25. Gliogenesis takes place between P25 and P34. We also found that monocular enucleation performed during the early period of retinal development (P0?P7) did not influence proliferation, developmental apoptosis or other developmental processes in the retina of the remaining eye.
4
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Evolutionary ancient roles of serotonin: long-lasting regulation of activity and development

80%
Turlejski K.
Acta Neurobiologiae Experimentalis
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1996
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vol. 56
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issue 2
619-636
EN
Biogenic monoamines (catecholamines, indoleamines and histamine) are evolutionary old and important modulators of long-lasting changes in the functional state of cells.They are found in many protozoans and in almost all metazoans.Monoamines preserve their evolutionary old functions (first of all being intracellular signals and later hormones and growth factors) even in those animals in which they acquired the function of neurotrasmitter.The older functions of serotonin, an important member of the family of indoleamines, are reviewed here.Described are: presence of serotonin on organisms at various phylogenetic levels; its role in embryonal, foetal and postnatal nervous system.It is concluded that in none of these functions serotonin is the only factor, but it is an ubiquitous and important modulator of a vast array of processes and functions taking part in development and plasticity.
5
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Jerzy Konorski on brain associations

80%
Zielinski K.
Acta Neurobiologiae Experimentalis
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2006
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vol. 66
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issue 1
75-90
EN
Jerzy Konorski (1903?1973) exerted a vital influence on the development of physiological psychology and neurobiology. Konorski and his friend and collaborator, Stefan Miller, distinguished instrumental conditioned reflexes as a separate type of acquired behavior, different from classical (Pavlovian) conditioned reflexes. In a series of pioneering studies Konorski demonstrated basic differences between the two types of conditioned reflexes. After the Second World War, he reinterpreted the results of research on conditioned reflexes on the basis of the mechanisms of Sherringtonian neurophysiology and introduced the term plasticity of the nervous system. His work, 'Conditioned reflexes and neuron organization', published in 1948, signaled Konorski's place as one of the founders of contemporary neuroscience. He contributed significantly to the understanding of complex interactions of various classes of behaviors: innate and acquired, those driven by opposite motivations, and those elicited by cues signaling different contingencies. In his book ' 'Integrative activity of the brain' (1967), Konorski analyzed the brain as a complex system directing the functioning of the organism as a whole.
6

The migration of bone marrow-derived non-hematopoietic tissue-committed stem cells is regulated in an SDF-1-, HGF-, and LIF-dependent manner

80%
Kucia M., Wojakowski W., Reca R., Machalinski B., Gozdzik J., Majka M., Baran J., Ratajczak J., Ratajczak M. Z.
Archivum Immunologiae et Therapiae Experimentalis
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2006
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vol. 54
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issue 2
121-135
EN
Introduction: Recently we identified in bone marrow (BM) by employing chemotactic isolation to SDF-1 gradient combined with real time RT-PCR analysis a mobile population of CXCR4+ BM mononuclear cells that express mRNA for various markers of early tissue-committed stem cells (TCSCs). In this study we evaluated whether TCSCs respond to other moto-morphogens, such as hepatocyte growth factor (HGF) and leukemia inhibitory factor (LIF). Materials and Methods: We again employed chemotactic isolation combined with real-time RT-PCR analysis to assess whether murine and human BM contain TCSCs that respond to HGF and LIF gradients. We also evaluated expressions of HGF and LIF in damaged organs. Results: We noted that the number of TCSCs is highest in BM from young (1- to 2-month-old) mice and decreases in 1-year-old animals. Murine and human TCSCs 1) respond to HGF and LIF gradients in addition to an SDF-1 gradient, 2) reside in populations of BM-derived non-hematopoietic CD45? cells, and 3) are released (mobilized) from BM into the peripheral blood (PB) during tissue injury (e.g. after partial body irradiation). Conclusions: These findings further support our theory of the BM as a ?hideout' for TCSCs and we suggest that their presence in BM tissue should be considered before experimental evidence is interpreted simply as transdifferentiation/plasticity of hematopoietic stem cells. Since we demonstrated that not only SDF-1, but also HGF and LIF are upregulated in damaged tissues, we postulate that CXCR4+ c-Met+ LIF-R+ TCSC could be mobilized from the BM into the PB, from which they are subsequently chemoattracted to damaged organs, where they play a role in tissue repair/regeneration.
7
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Overlap of sensory representation in rat barrel cortex after neonatal vibrissectomy

80%
Kossut M., Siucinska E.
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EN
Cortical repesentation of the common fur of mysticial pad is situated outside poster-medial barrel subfield (PMBSF) in rat primary somatosensory cortex.Following neonatal vibrissectomy, stimulation of the common fur activates the neurone in PMBSF.We examined if sparing of the mystacial vibrissa from the neonatal ablation, which results in a very extensive increase of its cortical repesentation, would prevent the invasion of the common fur inputs into the PMBSF.The cortical representation were mapped with 2-deoxyglucose (2DG).It was found that six weeks after neonatal vibrissectomy sparing C3 vibrissa and common fur inputs were representes into the PMBSF.Their representation shifed from its normal location into the barriel field.This effect was observed in cortical layers II/III, IV and V.
8
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Brain preconditioning and obstructive sleep APNEA syndrome

70%
Brzecka A.
Acta Neurobiologiae Experimentalis
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2005
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vol. 65
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issue 2
213-220
EN
Intermittent hypoxia stimulates the development of adaptive responses, called preconditioning. This process is partially mediated by genetic remodeling, via hypoxia inducible factor (HIF), which induces long-term adaptation processes and is responsible for the increase of levels of vascular endothelial growth factor (VEGF), erythropoietin (Epo), atrial natriuretic peptide (ANP), and nitric oxide (NO). The synthesis of brain-derived neurotrophic factor (BDNF) participates in the control of neural plasticity after hypoxia. The mechanisms of neuroprotection against hypoxia may be related to vascular adjustments and to central neurogenic neuroprotection. Some of the factors known to be involved in the development of the mechanism of neuroprotection are also present in the responses to repetitive apneas that occur during sleep in patients with obstructive sleep apnea (OSA) syndrome, who are frequently exposed to severe sleep hypoxemia. It appears that OSA syndrome represents a clinical example of preconditioning and the development of adaptive responses to intermittent hypoxia.
9

Sexual dimorphism in life history plasticity in the gypsy moth (Lymantria dispar L.).

70%
Lazarevic J., Peric-Mataruga V.
Folia Biologica
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2003
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vol. 51
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issue 3-4
227-229
EN
Sexual differences in reaction norms of life history traits (larval development time-LDT, pupal weight-PW and adult longevity-L) were investigated in the gypsy moth reared on young or old oak leaves during the first larval instar. Sexual dimorphism was revealed for genetic variation in reaction norms that was expressed only for LDT in males, and PW and L in females. Higher mean plasticity of longevity was found in males compared to females indicating that the sexes are exposed to divergent selective pressures. Greater dependence of males on energy resources (carbohydrates and lipids) may account for the observed differences.
10
Content available remote

How does trimethyltin affect the brain:facts and hypotheses

70%
Koczyk D.
Acta Neurobiologiae Experimentalis
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1996
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vol. 56
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issue 2
587-596
EN
Trimethyltin, an organic compound of tin, is a potent neurotoxicant of mechanism of action yet to be uncovered.The neuropathological findings that causes selective hippocampal damage with several unique features, highly reminiscent of Ammon's horn sclerosis as a final result, have rised the possibility that there is a link between trimethyltin neurotoxicity and other degenerative events for which an imbalance between neuronal inhibition/excitation has been proposed.However, there still exist a whole catalog of issues which await clarification.One of the greatest importance is how does trimethyltin reach the critical sites within the brain and what are they ? Available data concerning the long-term consequences related to trimethyltin neurotoxicity are also far from being completed.This review current data from in vitro and in vivo studies on neurotoxic effects of trimethyltin.Several hypotheses on mechanisms that may led to neuronal death induced by the toxin are presented.
11
Content available remote

Characterization and plasticity of the double synapse spines in the barrel cortex of the mouse

70%
Jasinska M., Siucinska E., Glazewski S., Pyza E., Kossut M.
Acta Neurobiologiae Experimentalis
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2006
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vol. 66
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issue 2
99-104
EN
The somatosensory barrel cortex of rodents and its afferent pathway from the facial vibrissae is a very useful model for studying neuronal plasticity. Dendritic spines are the most labile elements of synaptic circuitry and the most likely substrate of experience ? dependent alterations in neuronal circuits in cerebral cortex. We characterized morphologically and numerically a specific population of spines, i.e. double synapse spines, which have two different inputs ? one excitatory and the other inhibitory, in the B2 barrel of mouse somatosensory cortex. We also described changes in morphology of double synapse spines induced by classical conditioning in which stimulation of vibrissae was paired with a tail shock. The analysis was carried out by means of serial EM micrograph reconstruction. We showed that double spines account for about 10% of all analyzed spines. The morphology of a typical double synapse spine is similar to the morphology of single synapse spine and both consist of two parts ? a large head and a narrow, long neck. Excitatory synapses are preferentially located on the head of double synapse spines and inhibitory synapses are usually located on the neck of these spines. The length of the double synapse spine neck decreases and the cross-section area of the spine neck increases significantly as a result of sensory conditioning.
12
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Focal stroke in the barrel cortex of rats enhances ipsilateral response to vibrissal input

70%
Jablonka J., Kossut M.
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EN
Brain injury triggers spontaneous plasticity, often resulting in considerable restoration of function. To investigate mechanisms of this compensatory plasticity we followed changes in the brain's pattern of activation evoked by stimulation of vibrissae, after a focal cortical stroke which destroyed the cortical representation of vibrissae, the barrel cortex. The pattern of brain activation was visualized with [14C]-2-doexyglucose (2DG) autoradiography in rats 7 days after photothrombotic stroke. During isotope incorporation, vibrissae contralateral to stroke were stimulated. In control rats this stimulation activates the barrel cortex and the second somatosensory cortex in the contralateral hemisphere. Seven days after stroke in the barrel cortex, significant increases in activation were found in ipsilateral, uninjured hemisphere in the barrel cortex and anterior vibrissae representation, and also in regions not specifically connected to vibrissae stimulation, such as motor and auditory cortex. Shortly after cortical stroke, the intact hemisphere shows higher metabolic activation in several cortical regions, possibly due to abnormal interactions with the injured hemisphere.
13
Content available remote

Functional plasticity and neurotransmitter receptor binding in the vibrissal barrel cortex

61%
Kossut M., Glazewski S., Siucinska E., Skangiel-Kramska J.
Acta Neurobiologiae Experimentalis
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1993
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vol. 53
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issue 1
161-173
EN
A form of activity dependent, functional plasticity can be induced in the barrel cortex by sensory deprivation without damage to the sensory receptors. Changes of cortical representation of a spared C3 vibrissa, when all other whiskers were plucked out, were mapped with 2-deoxyglucose autoradiography in mice and rats after a short-lasting deprivation. An increase in the volume of cortical column activated by the spared vibrissa was found previously that if deprivation is commenced immediately after birth, yhe changes in cortical representation of the spared whisker appeared in the third week of life. In search of a possible reason for the delayed expression of functional plasticity in neonatal animals we examined the developmental curves of neurotransmitter receptor binding for several transmitters thought to be involved in plstic processes of the cerebral cortex. We found that the beta noradrenergic and miscarinic cholinergic receptor binding increased rapidly at the end of the second postnatal week and subsequently remained high. By contrast, the metabotropic glutamate receptor binding decreased during the first month of postnatal development. The AMPA receptors binding values rose during the first two weeks of life, and then decreased. Together with our previous data on the development of NMDA and GABA receptor and voltage dependent calcium channel binding, the results suggest that slow development of functional plasticity in neonatal animals may be due to low levels of receptors of several neurotransmitters implicated in brain plasticity.
14
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Inducing gene expression in barrel cortex - focus on immediate early genes

61%
Filipkowski R. K.
Acta Neurobiologiae Experimentalis
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2000
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vol. 60
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issue 3
411-418
EN
Using only their vibrissae, rats and mice are able to recognize and differentiate surfaces not distinguishable by primates using their fingertips. It has been shown that sensory stimulation elicits the expression of immediate-early genes (IEG), e.g., c-fos and zif268, in the sensory cortex of rats and mice. Though most of these findings come from visual system, mice and rats rely more on their vibrissal system which also offers many advantages for designing precise and precisely controlled experiments. In this review, new models for the selective and simple stimulation of vibrissae are presented and discussed. The data demonstrating IEG expression in the vibrissal system is also reviewed.
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