| 1. |
- Niklasson, Magnus, et al.
(författare)
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Effects of GABAB activation and inhibition on vestibulo-ocular and optokinetic responses in the pigmented rat
- 1994
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Ingår i: Brain Research. - : Elsevier. - 0006-8993 .- 1872-6240. ; 649:1-2, s. 151-158
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Tidskriftsartikel (refereegranskat)abstract
- The effects of the GABAB agonist baclofen and the GABAB antagonist CGP 35348, given separately or simultaneously, on the central vestibular system of pigmented rats have been evaluated. Drugs were administered either intramuscularly or intracerebroventricularly. Eye movements were recorded during vestibular, optokinetic and combined visual-vestibular stimulation. Activation of the GABAB receptors by baclofen caused a dose related disturbance of the system, manifested by (1) a decrease of the optokinetic gain, (2) a reduced ability to suppress nystagmus during conflicting vestibular and visual input, and (3) a disability to maintain the eccentric eye position upon a spontaneous saccade. All these effects could be inhibited in a dose-dependent fashion by CGP 35348, suggesting that the findings are specifically related to the GABAB receptor. Given separately, the antagonist did not affect the mentioned parameters. During horizontal acceleratory/deceleratory stimulation in darkness baclofen caused a biphasic pattern in the dose-response curves. Small amounts of baclofen caused an increase of the gain and of the duration of poststimulatory nystagmus, while high doses had a depressive action on the same parameters. The stimulating effect of baclofen could be inhibited or even reversed by CGP 35348, which has a depressive effect per se, similar to the effects of baclofen given in the upper range of doses.
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| 2. |
- Niklasson, Magnus, et al.
(författare)
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Effects of toluene, styrene, trichloroethylene, and trichloroethane on the vestibulo- and opto-oculo motor system in rats
- 1993
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Ingår i: Neurotoxicology and Teratology. - 0892-0362 .- 1872-9738. ; 15:5, s. 327-334
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Tidskriftsartikel (refereegranskat)abstract
- The acute effects of inhalation of four solvents on the central vestibular system of rats were analyzed by recording eye movements upon different stimuli. The dose-response relationship was investigated. Optokinetic stimulation was obtained by placing the animals in front of a surrounding visual pattern, moving at different velocities. The slow-phase eye velocity (SPV) of nystagmus was calculated and divided by the stimulus velocity, giving the gain. All the solvents caused a decrease of the gain. Vestibular stimulation was performed on a turntable by an angular acceleration/deceleration in darkness. The SPV and the duration of the post-stimulatory nystagmus were calculated. The shape of the SPV dose-response curves differed among the four solvents. Toluene, styrene, and trichloroethylene prolonged the duration of nystagmus while trichloroethane did not. A conflicting vestibular and optokinetic stimulation was performed by an angular acceleration/deceleration with a surrounding visual pattern moving with the turntable. All solvents decreased the ability to cancel nystagmus, elicited by vestibular stimulation in conflict with a visual input. Quick movements of the eyes, saccades, were elicited by tactile stimulation. Toluene, styrene, and trichloroethylene changed the generation of the saccades while trichloroethane did not. Most of the findings indicate a common site of action in the central vestibular system, viz., the cerebellar-vestibular circuit. However, within this domain, there are evident differences in the effects among the solvents. This finding, together with previous results obtained in other experimental models of the central nervous system (CNS), suggest that different solvents should be considered as individual compounds. While the current results are consistent with the notion that solvents affect cerebellar-vestibular function, they also demonstrate differences on selected components of this system which may be of concern.
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| 3. |
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| 4. |
- Niklasson, Magnus, et al.
(författare)
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The influence of visual and somatosensory input on the vestibulo-oculomotor reflex of pigmented rats
- 1991
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Ingår i: Journal of Vestibular Research-Equilibrium & Orientation. - 0957-4271 .- 1878-6464. ; 1:3, s. 251-262
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Tidskriftsartikel (refereegranskat)abstract
- Eye movements were recorded in the pigmented rat during vestibular, optokinetic and combined visual-vestibular stimulation. The dominant time constant in pigmented rats, tested during angular vestibular stimulation in darkness, is about two times longer than the cupular time constant. The gain and the duration of nystagmus, achieved by angular vestibular stimulation, can be enhanced by visual impulses. This is most evident during an optokinetic temporonasal stimulation, but is also seen with a nasotemporal stimulation. A mere optokinetic monocular stimulation without a synchronous vestibular excitation causes nystagmus only when the stimuli has a temporonasal direction. The duration of nystagmus, achieved by angular vestibular stimulation, is prolonged by disturbances of the neck proprioceptive system. This is more evident during a simultaneous visual input than in darkness. The ability to cancel nystagmus during conflicting vestibular and optokinetic impulses is well developed in the pigmented rat.
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| 5. |
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| 6. |
- Tham, Richard, et al.
(författare)
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The effect of toluene on the vestibulo- and opto-oculomotor system in rats, pretreated with GABAergic drugs
- 1990
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Ingår i: Neurotoxicology and Teratology. - : Elsevier. - 0892-0362 .- 1872-9738. ; 12:4, s. 307-311
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Tidskriftsartikel (refereegranskat)abstract
- Toluene, an aromatic solvent, prolongs the duration of nystagmus induced by a rotatory acceleration or by an optokinetic stimulation in the pigmented rat. Baclofen, an agonist of GABAB receptors, and 4,5,6,7-tetrahydroisoxazolo[5,4-c]-pyridin-3-ol (THIP), an agonist of GABAA receptors are able to block this toluene effect on the vestibular system. On the contrary diazepam, which by itself causes an evident reduction of the duration of acceleratory nystagmus, is not able to block the toluene effect. The results indicate that the toluene effect is related to GABA transmission and that the solvent interacts by a rather receptor specific mechanism of action.
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| 7. |
- Almevall, Albin Dahlin, et al.
(författare)
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Associations between everyday physical activity and morale in older adults
- 2022
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Ingår i: Geriatric Nursing. - : Elsevier. - 0197-4572 .- 1528-3984. ; 48, s. 37-42
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Tidskriftsartikel (refereegranskat)abstract
- Studies that objectively investigate patterns of everyday physical activity in relation to well-being and that use measures specific to older adults are scarce. This study aimed to explore objectively measured everyday physical activity and sedentary behavior in relation to a morale measure specifically constructed for older adults. A total of 77 persons (42 women, 35 men) aged 80 years or older (84.3 ± 3.8) wore an accelerometer device for at least 5 days. Morale was measured with the Philadelphia Geriatric Center Morale Scale (PGCMS). PGCMS scores were significantly positively associated with number of steps, time spent stepping, and time spent stepping at >75 steps per minute. Sedentary behavior did not associate with PGCMS. Promoting PA in the form of walking at any intensity–or even spending time in an upright position—and in any quantity may be important for morale, or vice versa, or the influence may be bidirectional.
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| 8. |
- Almevall, Ariel, et al.
(författare)
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Self-rated health in old age, related factors and survival: A 20-Year longitudinal study within the Silver-MONICA cohort
- 2024
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Ingår i: Archives of gerontology and geriatrics (Print). - : Elsevier. - 0167-4943 .- 1872-6976. ; 122
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Self-rated health (SRH) offers insights into the evolving health demographics of an ageing population.Aim: To assess change in SRH from old age to very old age and their associations with health and well-being factors, and to investigate the association between SRH and survival.Methods: All participants in the MONICA 1999 re-examination born before 1940 (n = 1595) were included in the Silver-MONICA baseline cohort. The Silver-MONICA follow-up started in 2016 included participants in the Silver-MONICA baseline cohort aged 80 years or older. Data on SRH was available for 1561 participants at baseline with 446 of them also participating in the follow-up. The follow-up examination included a wide variety of measurements and tests.Findings: Most participants rated their health as "Quite good" (54.5 %) at baseline. Over the study period, 42.6 % had stable SRH, 40.6 % had declined, and 16.8 % had improved. Changes in SRH were at follow-up significantly associated with age, pain, nutrition, cognition, walking aid use, self-paced gait speed, lower extremity strength, independence in activities of daily living, weekly physical exercise, outdoor activity, participation in organized activities, visiting others, morale, and depressive symptoms. SRH at baseline was significantly associated with survival (p < 0.05).Conclusion: This study demonstrates associations between changes in SRH and a multitude of health- and wellbeing-related factors, as well as a relation between survival and SRH, accentuating their relevance within the ageing population.
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| 9. |
- Bach, Tobias, et al.
(författare)
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The role of agencies in policy-making
- 2012
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Ingår i: Policy and Society. - : Oxford University Press (OUP). - 1449-4035 .- 1839-3373. ; 31:3, s. 183-193
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Tidskriftsartikel (refereegranskat)abstract
- There is an extensive literature on the proliferation of agencies and the delegation of authority to such bodies across different countries. Much of this research asks whether New Public Management (NPM)-style agencification reforms have been implemented according to the original objectives, and what consequences – intended or unintended – the reforms have produced. Yet much of this research lacks an explicit link to the literature on the policymaking functions of public bureaucracies and their interactions with elected politicians. What are the consequences of agencification for the policy process at large? What policy relevant tasks do agencies perform, to what extent are they involved in policy-making, and what factors influence the quality and quantity of their participation? This introductory article gives an overview of key concepts such as “public agencies” and “policy autonomy” and the research literature. Moreover, it critically discusses relevant theoretical perspectives, outlines the articles included in this themed issue and argues for a more systematic and theoretically guided analysis of agencies’ role in policy-making.
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