| 11. |
- Cottino, A, et al.
(author)
-
Die Schwedische Rechtshilfereform
- 1978
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In: Rechtsbedürfnis und Rechtshilfe. - Opladen : Westdeutscher Verlag. - 3531114506 ; , s. 162-174
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Book chapter (other academic/artistic)
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| 12. |
- Fredriksson, K, et al.
(author)
-
Cerebral microangiopathy in stroke-prone spontaneously hypertensive rats. An immunohistochemical and ultrastructural study
- 1988
-
In: Acta Neuropathologica. - 1432-0533. ; 75:3, s. 241-252
-
Journal article (peer-reviewed)abstract
- The morphology of cerebral microvessels was studied immunohistochemically and ultrastructurally in 6- to 9-month-old normotensive Wistar-Kyoto rats (WKY), spontaneously hypertensive rats (SHR), and stroke-prone SHR (SHRSP) with a systolic blood pressure of 138 +/- 15 mm Hg, 189 +/- 9 mm Hg, and 258 +/- 30 mm Hg respectively. Regions with major opening of the blood-brain barrier (BBB) were revealed by an i.v. injection of Evans Blue. Multifocal BBB opening with massive leakage of plasma constituents rich in fibrinogen-fibrin-related antigen occurred in SHRSP with a blood pressure above 210-220 mm Hg. BBB-leakage sites were found in the cerebral cortex and the basal ganglia, most frequently in the arterial border zones. The perivascular tissue spaces were dilated within the BBB-leakage sites, in particular around arterioles. Damaged endothelial and smooth muscle cells were replaced by fibrin-like material, multiple layers of basement membranes and bundles of collagen fibrils surrounded by proliferated fibroblasts. The degenerative-infiltrative-proliferative disease process transformed short segments of single arterioles into severely thickened, tortuous and stenotic vessels. Fibrinoid degeneration, formation of microaneurysms and fibrin-rich vascular occlusions were observed. In contrast, only minor or no vascular alterations were seen in regions with preserved BBB in SHRSP and SHR. A severely increased intraluminal pressure load appears to be of major pathogenetic importance for breakdown of the BBB and initiation of the vascular disease process in SHRSP. However, since only short segments of a limited number of widely separated vessels are severely affected, and the number of affected vessels increase towards arterial end and border zones, additional predisposing and aggravating factors may play significant roles in the development of fibrinoid vascular lesions in arterial hypertension.
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| 13. |
- Fredriksson, K, et al.
(author)
-
Cerebrovascular lesions in stroke-prone spontaneously hypertensive rats
- 1985
-
In: Acta Neuropathologica. - 1432-0533. ; 68:4, s. 284-294
-
Journal article (peer-reviewed)abstract
- The cerebrovascular lesions of severe chronic hypertension were studied by light microscopy in perfusion-fixed, subserially sectioned brains from stroke-prone spontaneously hypertensive rats (SHRSP). The leakage and spread of plasma proteins were visualized by immunohistochemical detection of extravasated fibrinogen and by using an exogenous marker (Evans blue injected i.v.) for blood-brain barrier (BBB) dysfunction. In most SHRSP the hypertension did not lead to major BBB lesions in spite of a mean arterial pressure around 200 mm Hg at 6-9 months of age. Multifocal BBB damage occurred in a minor group of SHRSP, particularly within the cortex and the deep gray matter. A close spatial correlation was found between the leakage-spread of plasma constituents and the neuropathologic alterations. Fibrinoid degeneration of penetrating arterioles was found within the leakage sites. The surrounding gray matter showed petechial hemorrhages and abundant proteinaceous exudates rich in antifibrinogen-positive material. The current leakage of Evans blue and wide spread of fibrinoid substances suggested long-lasting damage to the BBB. Most neurons within the edematous gray matter had well preserved nuclei surrounded by a rim of cytoplasm with ill-defined outline as if vacuolation or lysis of the peripheral cytoplasm had occurred. The sponginess of the tissue progressed in severe cases to formation of necrotic cysts. Condensed acidophilic neurons were seen in the border zone between the edematous and more compact gray matter. The appearance and distribution of the gray matter lesions deviated in many respects from those commonly seen in regional ischemic infarcts. The fibrin thrombi found close to the cysts might be regarded as secondary events. The extensive spread of antifibrinogen-positive material within the white matter seemed to originate mainly from the chronic leakage sites in the gray matter. Increased number of large astrocytes were seen within the leakage sites and along the spreading pathways for the edema constituents. The white matter showed a rarefied texture with widely dispersed nerve fiber tracts, volume expansion, and occasional cyst formation. The results indicate a crucial pathophysiologic role for the egress, spread, and accumulation of vasogenic edema in the development of the cerebrovascular lesions in SHRSP.
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| 14. |
- Fredriksson, K, et al.
(author)
-
Cyst formation and glial response in the brain lesions of stroke-prone spontaneously hypertensive rats
- 1988
-
In: Acta Neuropathologica. - 1432-0533. ; 76:5, s. 441-450
-
Journal article (peer-reviewed)abstract
- The brain lesions in spontaneously hypertensive stroke-prone rats (SHRSP) are characterised by multifocal microvascular damage, breakdown of the blood-brain barrier, massive extravasation of plasma constituents and severe brain oedema, with consequent spongy and cystic tissue destruction in the cerebral cortex and basal ganglia as well as loosening of the white matter. In this paper we analyse in greater detail the pathogenetic mechanisms by which the spongy and cystic lesions are formed and the response of astrocytic cells. For this purpose, tracer (Evans blue)-stained brain lesions were examined in 8-month-old SHRSP immunohistochemically and electron microscopically. Sponginess of the neuropil in small lesions and at the periphery of larger lesions was due to swollen neuronal and astrocytic cell processes, i.e. at this stage the oedema was mainly intracellular. Cystic lesions were formed in the grey matter both by expansion of the extracellular space (ECS) containing protein-rich oedema fluid, and by rupture and subsequent loss of massively swollen cellular elements. In the white matter small slit-formed cysts along the fibre tracts were also formed by the expansion of ECS. In apparently recent lesions astrocytes displayed cyto-plasmic oedema but otherwise were still fairly normal. In more chronic lesions increased numbers of enlarged astrocytes with prominent staining for glial fibrillary acidic protein were present. Their distribution corresponded well to the spread of oedema, i.e. they were prominent around the leaky vessels in the grey matter, in the subpial zone and in the white matter. In the reparative phase the grey matter cysts became lined by astrocytic processes, a new glia limitans. Profuse sheets of glial processes in the neuropil around the cysts reestablished the compactness of the brain parenchyma.
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| 15. |
- Fredriksson, K, et al.
(author)
-
Nerve cell injury in the brain of stroke-prone spontaneously hypertensive rats
- 1988
-
In: Acta Neuropathologica. - 1432-0533. ; 76:3, s. 227-237
-
Journal article (peer-reviewed)abstract
- The brain lesions in stroke-prone spontaneously hypertensive rats (SHRSP) are characterized by multifocal microvascular and spongy-cystic parenchymal alterations particularly in the gray matter. An essential feature of the lesions is the presence of edema with massive extravasation of plasma constituents as evidenced by specific gravity measurements, Evans blue technique and immunohistochemistry. The nerve cell injury occurring in the brain lesions in SHRSP is further characterized by light and electron microscopy in the present study. Two types of neuronal changes were seen within the blood-brain barrier (BBB) leakage sites. A small number of neurons with dark condensed nucleus and cytoplasm were found most often at the periphery of recent lesions. The majority of injured neurons were pale and showed intracellular edema confined to the dendrites and perikarya sparing axons and synapses. Their nuclei were well preserved with finely dispersed chromatin. The swollen and watery cell processes of neurons and astrocytes gave a spongy appearance to the neuropil. The intracellular edema seemed to result in cytolysis. The results suggest that primary anoxia-ischemia is not the major pathogenetic mechanism behind the nerve cell injury in severely hypertensive SHRSP, rather it is the massive BBB leakage and consequent brain edema that causes cytolytic destruction of neurons. Secondary focal ischemia as a consequence of occlusion in microvessels may, however, contribute to the nerve cell destruction.
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| 16. |
- Grabowski, Martin, et al.
(author)
-
Brain capillary density and cerebral blood flow after occlusion of the middle cerebral artery in normotensive Wistar-Kyoto rats and spontaneously hypertensive rats
- 1993
-
In: Journal of Hypertension. - 1473-5598. ; 11:12, s. 1363-1368
-
Journal article (peer-reviewed)abstract
- OBJECTIVE: In order to elucidate why spontaneously hypertensive rats (SHR) develop larger brain infarcts distal to an arterial occlusion than normotensive Wistar-Kyoto (WKY) rats, we determined the surface and volume densities of cerebral capillaries, and the regional cerebral blood flow distal to an arterial occlusion in SHR and WKY rats. DESIGN: Occlusion of the middle cerebral artery was chosen because the middle cerebral artery territory is most commonly affected by cerebral infarcts in man. METHODS: Surface and volume densities of capillaries in the neocortex of the middle cerebral artery territory were measured by stereological techniques on histological sections. Fifteen minutes after ligation of the right middle cerebral artery, regional cerebral blood flow was measured autoradiographically by the [14C]-iodoantipyrine method. RESULTS: The capillary density of the neocortex did not differ between the SHR and WKY rats. The blood flow was significantly lower within the middle cerebral artery territory in the SHR than in the WKY rats. CONCLUSIONS: The reduced blood flow distal to the occlusion in SHR is probably a consequence of structural adaptation of arterial resistance vessels, rather than being caused by reduced capillary density.
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| 17. |
- Jakobsson, Mattias, et al.
(author)
-
A unique recent origin of the allotetraploid species Arabidopsis suecica: Evidence from nuclear DNA markers
- 2006
-
In: Molecular biology and evolution. - : Oxford University Press (OUP). - 0737-4038 .- 1537-1719. ; 23:6, s. 1217-1231
-
Journal article (peer-reviewed)abstract
- A coalescent-based method was used to investigate the origins of the allotetraploid Arabidopsis suecica, using 52 nuclear microsatellite loci typed in eight individuals of A. suecica and 14 individuals of its maternal parent Arabidopsis thaliana, and four short fragments of genomic DNA sequenced in a sample of four individuals of A. suecica and in both its parental species A. thaliana and Arabidopsis arenosa. All loci were variable in A. thaliana but only 24 of the 52 microsatellite loci and none of the four sequence fragments were variable in A. suecica. We explore a number of possible evolutionary scenarios for A. suecica and conclude that it is likely that A. suecica has a recent, unique origin between 12,000 and 300,000 years ago. The time estimates depend strongly on what is assumed about population growth and rates of mutation. When combined with what is known about the history of glaciations, our results suggest that A. suecica originated south of its present distribution in Sweden and Finland and then migrated north, perhaps in the wake of the retreating ice.
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| 18. |
- Kahrstrom, J, et al.
(author)
-
A morphometric study of the effect of bilateral cervical sympathetic ganglionectomy on the architecture of pial arteries in spontaneously hypertensive and normotensive rats
- 1994
-
In: Acta Physiologica Scandinavica. - 0001-6772. ; 152:4, s. 407-418
-
Journal article (peer-reviewed)abstract
- The influence of the cranial sympathetic nerves on the architecture of pial arteries in normo- and hypertension was examined. For this purpose the effect of bilateral superior cervical ganglionectomy was evaluated in normotensive rats (WKY) and stroke-prone spontaneously hypertensive rats (SHRSP). The operations were performed at the age of 1 wk, which is just prior to the onset of ganglionic transmission. The length of the inner media contour was measured and the media cross-sectional area was determined planimetrically, with computerized digitalization of projected photographic images of transversely sectioned pial arteries. Four wk after sympathectomy there was a 20% reduction in media cross-sectional area and a consequent reduction in the ratio between media area and calculated luminal radius in the major pial arteries at the base of the brain in WKY but not in SHRSP. Conversely, in small pial arteries linear regression analysis showed that in WKY subjected to ganglionectomy the relationship between media cross-sectional area and luminal radius was significantly larger in arteries with a radius less than 21 microns compared to untreated WKY. No such effect was seen in the corresponding SHRSP vessels. In addition, the cross-sectional area of the internal elastic membrane (IEM) in the basilar arteries of WKY was measured by means of a computerized image-analysing system. Mean cross-sectional area of the IEM was approximately 45% larger following SE than in control animals. The present findings propose a 'trophic' role for the sympathetic perivascular nerves in large pial arteries of the rat. The increased media-radius ratio in the small pial arteries of the WKY following sympathectomy might reflect a compensatory hypertrophy due to reduced protection from the larger arteries against the pressure load. The inability to detect any morphometrically measurable effect of the sympathectomy in the cerebral arteries of SHRSP is probably explained by a marked growth-stimulating effect of the high pressure load in these animals.
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| 19. |
- Kawakatsu, Taiji, et al.
(author)
-
Epigenomic Diversity in a Global Collection of Arabidopsis thaliana Accessions
- 2016
-
In: Cell. - : Elsevier. - 0092-8674 .- 1097-4172. ; 166:2, s. 492-505
-
Journal article (peer-reviewed)abstract
- The epigenome orchestrates genome accessibility, functionality, and three-dimensional structure. Because epigenetic variation can impact transcription and thus phenotypes, it may contribute to adaptation. Here, we report 1,107 high-quality single-base resolution methylomes and 1,203 transcriptomes from the 1001 Genomes collection of Arabidopsis thaliana. Although the genetic basis of methylation variation is highly complex, geographic origin is a major predictor of genome-wide DNA methylation levels and of altered gene expression caused by epialleles. Comparison to cistrome and epicistrome datasets identifies associations between transcription factor binding sites, methylation, nucleotide variation, and co-expression modules. Physical maps for nine of the most diverse genomes reveal how transposons and other structural variants shape the epigenome, with dramatic effects on immunity genes. The 1001 Epigenomes Project provides a comprehensive resource for understanding how variation in DNA methylation contributes to molecular and non-molecular phenotypes in natural populations of the most studied model plant.
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| 20. |
- Kåhrström, J, et al.
(author)
-
Neonatal pre-ganglionic sympathectomy affects morphometrically defined architecture in rat cerebral arteries
- 1996
-
In: Acta Physiologica Scandinavica. - 0001-6772. ; 157:2, s. 225-231
-
Journal article (peer-reviewed)abstract
- In order to clarify further the nature of the long-term influence on the cerebral vasculature by the sympathetic nerves, a bilateral cervical pre-ganglionic denervation was performed in 1-week-old rats. Four weeks later, morphometric determinations of the vascular dimensions revealed diminished media cross-sectional areas and luminal radii in the middle cerebral and posterior cerebral arteries, whereas these parameters were unaffected in the basilar artery. In the latter artery, however, a 40% increase in the cross-sectional area of the internal elastic membrane was found. No re-innervation of the denervated ganglia occurred during the course of the experiment. The results suggest that the long-term effect exerted by the sympathetic nerves is associated with the nerve activity, rather than being a true trophic influence.
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