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| 2. |
- Bauer, H C, et al.
(författare)
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The Scandinavian Sarcoma Group Register 1986-2001.
- 2004
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Ingår i: Acta orthopaedica Scandinavica. Supplementum. - : Medical Journals Sweden AB. - 0300-8827 .- 0001-6470. ; 75:Supplement 311, s. 8-10
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Björklund, A, et al.
(författare)
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Reafferentation of the subcortically denervated hippocampus as a model for transplant-induced functional recovery in the CNS
- 1990
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Ingår i: Progress in Brain Research. - 0079-6123. ; 83, s. 411-426
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Forskningsöversikt (refereegranskat)abstract
- Subcortical deafferentation of the hippocampal formation is known to induce profound behavioural deficits. Transplants of fetal septal or brainstem tissue are capable of restoring some aspects of normal physiological and behavioural function in subcortically deafferented (i.e. fimbria-fornix or septal lesioned) rats. Such grafts have been shown to re-establish extensive new afferent inputs to the denervated hippocampal formation. As shown for grafted cholinergic and noradrenergic neurons, the ingrowing axons form laminar innervation patterns which closely mimic those of the normal cholinergic and noradrenergic innervations. The ingrowth appears to be very precisely regulated by the denervated target: each neuron type produces distinctly different innervation patterns; the growth is inhibited by the presence of an intact innervation of the same type; and it is stimulated by additional denervating lesions. Both ultrastructually and electrophysiologically the graft-derived fibres have been seen to form extensive functional synaptic contacts. Biochemically, cholinergic septal grafts and noradrenergic locus coeruleus grafts restore transmitter synthesis and turnover in the reinnervated hippocampus. Intracerebral microdialysis has revealed that acetylcholine and noradrenaline release is restored to normal or supranormal levels in the graft-reinnervated hippocampus, and that the grafted neurons can be activated in a normal way from the host through behavioural activation induced by sensory stimulation or electrical stimulation of the lateral habenula. These results indicate that the grafted monoaminergic neurons can restore tonic regulatory neurotransmission at previously denervated synaptic sites even when they are implanted into the ectopic brain sites. Such functional reafferentation may be sufficient for at least partial restoration of function in the subcortically deafferented hippocampus.
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| 4. |
- Cenci, M A, et al.
(författare)
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Characterization of in vivo noradrenaline release from superior cervical ganglia or fetal locus coeruleus transplanted to the subcortically deafferented hippocampus in the rat
- 1993
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886. ; 122:1, s. 73-87
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Tidskriftsartikel (refereegranskat)abstract
- Solid grafts of autologous superior cervical ganglia (SCG) or fetal locus coeruleus (LC) were implanted unilaterally into a fimbria-fornix lesion cavity adjacent to the hippocampal formation after a 6-hydroxydopamine lesion of the intrinsic noradrenergic system. Twelve to 15 months after transplantation, one microdialysis probe was implanted in the dorsal hippocampus ipsilateral to the graft, and extracellular levels of noradrenaline (NA) were monitored during the application of pharmacological or behavioral stimuli. Age-matched intact and lesion-only animals served as controls. Morphological examination of the grafts was performed on sections processed for dopamine-beta-hydroxylase (DBH) immunohistochemistry. In the lesion-only controls, the hippocampus was totally devoid of DBH-immunoreactive fibers and hippocampal levels of NA were generally undetectable. Although both SCG and LC grafts gave rise to an extensive DBH-immunoreactive fiber ingrowth in the ipsilateral hippocampus, baseline NA release was strikingly different in the two graft groups, being markedly lower than normal in the SCG-grafted rats (3.5 +/- 0.1 fmol/30 microliters) and significantly higher than normal in the LC-grafted rats (44.5 +/- 12.3 fmol/30 microliters). The response to potassium-induced depolarization (100 mM KCl in the perfusion fluid), neuronal uptake blockade (5 microM desipramine), and sodium-channel blockade (1 microM TTX) was similar to normal in both graft groups. Exposure of the animals to mild (handling) or severe (immobilization) stressful stimuli significantly enhanced NA release in the intact controls, whereas no clear-cut effect could be detected in either graft group. Electrical stimulation of the medial septum, applied in an attempt to activate possible afferents to the grafts from the host septum, did not enhance NA release in any of the groups. The results show that grafts of both central and peripheral noradrenergic neurons can provide a source of steady-state NA release in the denervated hippocampus, but that the spontaneous activity of the grafted ganglionic neurons is very low compared to that of the LC neurons, probably due to the absence of a functional preganglionic input to the grafted SCG neurons. Although extracellular NA recovered from both the SCG- and the LC-grafted hippocampi is likely to derive from impulse-dependent neuronal release, it was largely unaffected by physiological stimuli applied to the host.
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| 5. |
- Cenci, M. A., et al.
(författare)
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Serotonin release from mesencephalic raphe neurons grafted to the 5,7-dihydroxytryptamine-lesioned rat hippocampus : Effects of behavioral activation and stress
- 2000
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Ingår i: Experimental Neurology. - : Elsevier BV. - 0014-4886. ; 164:2, s. 351-361
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Tidskriftsartikel (refereegranskat)abstract
- Transplants of fetal midbrain raphe neurons into the adult brain have been shown to promote recovery of complex behavioral deficits in several experimental models, but the mechanisms underlying these effects are only partially understood. In the present study, we have used a well-characterized model system to ascertain whether midbrain raphe graft can display behaviorally relevant changes in transmitter release and/or metabolism. Fetal mesencephalic raphe neurons were grafted unilaterally into the hippocampus previously deprived of its innate serotonergic innervation by intraventricular injections of 5,7-dihydroxytryptamine. The contralateral hippocampus remained as a non-grafted, lesioned control. Microdialysis probes were implanted in the hippocampus 5-7 months postgrafting. Under baseline conditions, extracellular levels of serotonin were similar to normal in the grafted hippocampi, but undetectable on the contralateral, non-grafted side. Levels of the serotonin metabolite, 5-hydroxyindoleacetic acid (5-HIAA), were markedly higher than normal in the grafted hippocampi, but dramatically reduced on the contralateral nongrafted side. Handling stimulation (gentle stroking of a rat's fur and tail for 15 min) induced a 64% increase in serotonin output in the intact rats and a small but significant 12% increase in the grafted animals. Non-noxious tail-pinch (15 min) enhanced serotonin release by 86% in the intact rats and 28% in the grafted ones. Extracellular 5-HIAA levels remained unchanged during both handling and tail-pinch in both the intact and the grafted rats. Forced immobilization of the rats for 15 min induced a transient 124% increase in extracellular serotonin levels in the intact rats and a significant 19% increase in the grafted animals, whereas swimming in temperate water (25-30°C; 15 min) induced no detectable changes in serotonin output in any of the groups. 5-HIAA levels remained unchanged during forced immobilization, but were significantly reduced during the swimming session in both the intact (-38%) and grafted (-15%) animals. The present results indicate that median raphe grafts can become functionally integrated in the denervated host hippocampus and respond by altered indole output when the animal is exposed to different types of environmental challenges.
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| 6. |
- Felton, Adam, et al.
(författare)
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Correction to: Keeping pace with forestry : Multi-scale conservation in a changing production forest matrix (vol 49, pg 1050, 2020)
- 2020
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Ingår i: Ambio. - : Springer. - 0044-7447 .- 1654-7209. ; 49:5, s. 1065-1066
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Tidskriftsartikel (refereegranskat)abstract
- In the original published article, the sentence “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and over 2000 forest-associated species (of 15 000 assessed) are listed as threatened on Sweden’s red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015).”under the section Introduction was incorrect. The correct version of the sentence is “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and approximately 2000 forest-associated species (of 15 000 assessed) are on Sweden’s red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015).”
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| 9. |
- Kalén, P, et al.
(författare)
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Intracerebral microdialysis as a tool to monitor transmitter release from grafted cholinergic and monoaminergic neurons
- 1990
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Ingår i: Journal of Neuroscience Methods. - 0165-0270. ; 34:1-3, s. 15-107
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Tidskriftsartikel (refereegranskat)abstract
- In the present study the microdialysis technique has been used as a tool for the study of functional regulation of intracerebrally grafted cholinergic and monoaminergic neurons as well as for the analysis of graft-host interactions. Fetal noradrenergic, serotonergic, dopaminergic, and cholinergic neurons were transplanted into the hippocampus or striatum previously denervated of their intrinsic monoaminergic or cholinergic afferents. After a few months survival, when the grafts had reinnervated the surrounding target, dialysis probes were implanted into the graft-reinnervated region. Although the graft-derived fiber and terminal density varied substantially from one animal to another the transmitters in the extracellular space were maintained at near-normal levels, not only under baseline conditions, but also during K(+)-induced depolarization, transmitter-selective uptake blockade, and tetrodotoxin. This suggests that the grafted neurons possess efficient autoregulatory properties despite their ectopic location. The results also show that monoamine release in the graft-reinnervated host target is impulse-dependent, and that the neurons are spontaneously functionally active at the synaptic level. Electrical stimulation of the lateral habenula (which has previously been identified as a powerful activator of the intrinsic hippocampal cholinergic and noradrenergic afferents) produced a similar increase in the release of these transmitters in the intact and grafted hippocampi. A complex environmental stimulus, such as handling, induced a consistent increase in acetylcholine but not noradrenaline release in the hippocampus. These findings suggest that grafted cholinergic and noradrenergic neurons can be functionally activated by host brain inputs.
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| 13. |
- Nilsson, O G, et al.
(författare)
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Acetylcholine release from intrahippocampal septal grafts is under control of the host brain
- 1990
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424. ; 87:7, s. 51-2647
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Tidskriftsartikel (refereegranskat)abstract
- The activity of intrahippocampal transplants of cholinergic neurons was monitored by microdialysis in awake, freely moving rats. Fetal septal-diagonal band tissue was implanted into rats with a complete transection of the fimbria-fornix cholinergic pathway either as a cell suspension injected into the hippocampus or as a solid graft implanted in the lesion cavity. The grafts restored baseline acetylcholine release in the graft-reinnervated hippocampus to normal or supranormal levels. The graft-derived acetylcholine release was dependent on intact axonal impulse flow, and it was markedly increased during behavioral activation by sensory stimulation or by electrical stimulation of the lateral habenula. The results demonstrate that the septal grafts, despite their ectopic location, can become functionally integrated with the host brain and that the activity of the transplanted cholinergic neurons can be modulated from the host brain during ongoing behavior. Anatomical observations, using immunohistochemistry and retrograde tracing, indicate that direct or indirect brainstem afferents to the graft could mediate this functional integration. Host afferent control of the graft may thus play a role in the recovery of lesion-induced functional deficits seen with these types of transplants.
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| 14. |
- Nilsson, O G, et al.
(författare)
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Acetylcholine release in the rat hippocampus as studied by microdialysis is dependent on axonal impulse flow and increases during behavioural activation
- 1990
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Ingår i: Neuroscience. - : Elsevier BV. - 0306-4522. ; 36:2, s. 325-338
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Tidskriftsartikel (refereegranskat)abstract
- Changes in extracellular levels of acetylcholine and choline in the hippocampal formation were measured using intracerebral microdialysis coupled to high performance liquid chromatography with post-column enzyme reaction and electrochemical detection. Various pharmacological and physiological manipulations were applied to awake unrestrained normal rats and rats subjected to a cholinergic denervation of the hippocampus by a complete fimbria-fornix lesion (1-2 weeks previously). Low baseline levels of acetylcholine (about 0.3 pmol/15 min sample) could be detected in the absence of acetylcholinesterase inhibition in all animals. However, in order to obtain stable and more readily detectable levels, the acetylcholinesterase inhibitor neostigmine was added to the perfusion medium at a concentration of 5 or 10 microM and was used during all subsequent manipulations. Addition of neostigmine increased acetylcholine levels approximately 10-fold (to 3.7 pmol 15 min) in the normal rats, which was about 4-fold higher than the levels recovered from the denervated hippocampi. Depolarization by adding KCl (100 mM) to the perfusion fluid produced a 3-fold increase in the extracellular acetylcholine levels, and the muscarinic antagonist atropine (3 microM) resulted in a 4-fold increase in the normal rats, whereas these drugs induced only small responses in the denervated rats. Neuronal impulse blockade by tetrodotoxin (1 microM) resulted, in normal rats, in a 70% reduction in extracellular acetylcholine levels. Sensory stimulation by handling increased acetylcholine levels by 94% in the normal rats, whereas this response was almost totally abolished in the denervated hippocampi. Behavioural activation by electrical stimulation of the lateral habenula resulted in a 4-fold increase in acetylcholine release in normal animals, and this response was totally blocked by a transection of the lateral habenular efferents running in the fasciculus retroflexus. The levels obtained by lateral habenula stimulation were reduced by about 95% in the rats with fimbria-fornix lesions. Following an acute knife transection of the fimbria-fornix performed during ongoing dialysis, acetylcholine levels dropped instantaneously by 70%, indicating that the extracellular acetylcholine levels in the hippocampus are maintained by a tonic impulse flow in the septohippocampal pathway. The extracellular levels of choline were reduced by about 30% after the addition of neostigmine in the normal rats, and increased by about 50% in both normal and denervated rats after addition of KCl to the perfusion fluid. No changes could be detected after atropine, handling, lateral habenula stimulation, or acute fimbria-fornix or fasciculus retroflexus transection.(ABSTRACT TRUNCATED AT 400 WORDS)
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