| 1. |
- Mustafa, S, et al.
(författare)
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Hyperthermia-induced vasoconstriction of the carotid artery and the role of potassium channels
- 2005
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Ingår i: Journal of Stroke & Cerebrovascular Diseases. - : Elsevier BV. - 1052-3057 .- 1532-8511. ; 14:3, s. 122-126
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Tidskriftsartikel (refereegranskat)abstract
- Clinical experience and experimental studies have shown that hyperthermia can cause cerebral ischaemia and brain damage. By in vitro experiments with heating, we previously were able to induce carotid artery constriction. The objective of the present study was to clarify the mechanism of this thermal response. Isometric tension was recorded in rabbit carotid artery specimens using organ baths during stepwise temperature elevation. The heating responses were investigated at basal tone, in precontracted vessels, after blocking of adrenergic responses and administration of potassium (K)-channel activators and inhibitors. Stepwise heating of carotid artery strips from 37°C to 47°C induced reproducible graded contraction. The hyperthermic responses were not due to adrenergic stimulation, which were reduced and resistant to neurogenic blockade by tetrodotoxin. Heating-induced contractions were potentiated by the K-channel inhibitors tetraethylammonium, BaCl2, charybdotoxin, and the Na+/K+ ATPase inhibitor ouabain. Levcromakalim (BRL), a K+-channel activator, reduced heating induced contractions. Heating of carotid artery preparations induced reversible graded vasoconstriction proportional to temperature. The heating-induced contractions were not mediated by an adrenergenic process, but rather were due to inhibition of K+ channels, which increases Ca2+ entry. In vivo, this reaction may lead to a disturbance of autoregulation of cerebral blood flow and ischemia with brain damage. © 2005 by National Stroke Association.
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| 2. |
- Thulesius, Olav, 1930-, et al.
(författare)
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Human exposures to acrylamide are below the threshold for carcinogenesis
- 2004
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Ingår i: Human and Experimental Toxicology. - : Sage Publications. - 0960-3271 .- 1477-0903. ; 23:7, s. 357-358
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Tidskriftsartikel (refereegranskat)abstract
- Dose-response calculations for a threshold of carcinogenesis in animal studies do not support the notion that acrylamide (ACR) with the present status of consumption in food is carcinogenic for humans. This is in agreement with the recent reassuring epidemiological studies which have shown a lack of correlation between exposure to ACR in food and the incidence of cancer. © Arnold 2004.
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| 3. |
- Thulesius, Olav, 1930-
(författare)
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Phlebography and heparin for deep venous thrombosis introduced by Gunnar Bauer more than 60 years ago
- 2006
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Ingår i: Phlebology. - : SAGE Publications. - 0268-3555 .- 1758-1125. ; 21:3, s. 107-109
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Tidskriftsartikel (refereegranskat)abstract
- The story of a surgeon who in a country hospital in Sweden became a pioneer of modern phebology. He helped to set the standard of venography and heparin treatment for deep venous thrombosis and post-thrombotic valvular insufficiency more than 60 years ago. This happened when the surgeon Gunnar Bauer, stimulated by advancement in research and development of anticoagulants, introduced heparin treatment for deep venous thrombosis. He also started using descending phlebography for detection of venous reflux and advocated the controversial method of early ambulation after deep venous thrombosis. © 2006 Royal Society of Medicine Press.
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| 4. |
- Thulesius, Olav, 1930-
(författare)
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Thermal reactions of blood vessels in vascular stroke and heatstroke
- 2006
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Ingår i: Medical principles and practice. - : S. Karger AG. - 1011-7571 .- 1423-0151. ; 15:4, s. 316-321
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Tidskriftsartikel (refereegranskat)abstract
- Research on the pathophysiology and treatment of brain damage with special focus on thermal vascular responses is the subject of this minireview. Interruption of cerebral blood supply by vascular obstruction, temporary cardiac arrest or hyperthermia causes a sudden attack of vascular stroke or heatstroke with serious consequences. It may not induce immediate cell death, but can precipitate a complex biochemical cascade leading to a delayed neuronal loss. When testing thermal vasomotor responses by stepwise cooling of isolated carotid arteries, a temperature-proportional dilatation was observed while heating induced the opposite response: a marked vasoconstriction. General hyperthermia with an increased oxygen demand combined with a reduction of blood supply therefore is a serious consequence. At the cellular level an important mechanism involving hyperthermia is the temperature-dependent regulation of K+ channel tone of vascular smooth muscle. Further, their inhibition through temperature elevation causes vasoconstriction. In heatstroke, which can induce platelet aggregation and the release of the vasoconstrictor serotonin, arterial cooling attenuates this response. General hypothermia is induced to prevent or attenuate neurological damage in stroke. The procedure is not without serious side effects. Therefore, rapid institution of selective brain cooling has been considered in adults and in infants with postpartum encephalopathy. Copyright © 2006 S. Karger AG.
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| 5. |
- Thulesius, Olav, 1930-
(författare)
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Vensystemets fysiologi och patofysiologi
- 2002
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Ingår i: Klinisk fysiologisk kärldiagnostik. - Lund : Studentlitteratur AB. - 9789144021898 - 9144021895 ; , s. 245-254
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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