| 37601. |
- Johansson, Jarkko, et al.
(author)
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Amphetamine-induced dopamine release in rat : Whole-brain spatiotemporal analysis with [11C]raclopride and positron emission tomography
- 2024
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In: Journal of Cerebral Blood Flow and Metabolism. - : Sage Publications. - 0271-678X .- 1559-7016. ; 44:3, s. 434-445
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Journal article (peer-reviewed)abstract
- Whole-brain mapping of drug effects are needed to understand the neural underpinnings of drug-related behaviors. Amphetamine administration is associated with robust increases in striatal dopamine (DA) release. Dopaminergic terminals are, however, present across several associative brain regions, which may contribute to behavioral effects of amphetamine. Yet the assessment of DA release has been restricted to a few brain regions of interest. The present work employed positron emission tomography (PET) with [11C]raclopride to investigate regional and temporal characteristics of amphetamine-induced DA release across twenty sessions in adult female Sprague Dawley rats. Amphetamine was injected intravenously (2 mg/kg) to cause displacement of [11C]raclopride binding from DA D2-like receptors, assessed using temporally sensitive pharmacokinetic PET model (lp-ntPET). We show amphetamine-induced [11C]raclopride displacement in the basal ganglia, and no changes following saline injections. Peak occupancy was highest in nucleus accumbens, followed by caudate-putamen and globus pallidus. Importantly, significant amphetamine-induced displacement was also observed in several extrastriatal regions, and specifically in thalamus, insula, orbitofrontal cortex, and secondary somatosensory area. For these, peak occupancy occurred later and was lower as compared to the striatum. Collectively, these findings demonstrate distinct amphetamine-induced DA responses across the brain, and that [11C]raclopride-PET can be employed to detect such spatiotemporal differences.
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| 37602. |
- Johansson, Jörgen
(author)
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Battling the bureaucracy hydra
- 2016
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 351:6272, s. 530-530
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Journal article (other academic/artistic)
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| 37603. |
- Johansson, Jarkko, et al.
(author)
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Biphasic patterns of age-related differences in dopamine D1 receptors across the adult lifespan
- 2023
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In: Cell Reports. - 2211-1247. ; 42:9
-
Journal article (peer-reviewed)abstract
- Age-related alterations in D1-like dopamine receptor (D1DR) have distinct implications for human cognition and behavior during development and aging, but the timing of these periods remains undefined. Enabled by a large sample of in vivo assessments (n = 180, age 20 to 80 years of age, 50% female), we discover that age-related D1DR differences pivot at approximately 40 years of age in several brain regions. Focusing on the most age-sensitive dopamine-rich region, we observe opposing pre- and post-forties interrelations among caudate D1DR, cortico-striatal functional connectivity, and memory. Finally, particularly caudate D1DR differences in midlife and beyond, but not in early adulthood, associate with manifestation of white matter lesions. The present results support a model by which excessive dopamine modulation in early adulthood and insufficient modulation in aging are deleterious to brain function and cognition, thus challenging a prevailing view of monotonic D1DR function across the adult lifespan.
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| 37604. |
- Johansson, Johanna, 1983-, et al.
(author)
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Can voluntary standards regulate forestry? : Assessing the environmental impacts of forest certification in Sweden
- 2011
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In: Forest Policy and Economics. - : Elsevier BV. - 1389-9341 .- 1872-7050. ; 13:3, s. 191-198
-
Journal article (peer-reviewed)abstract
- This article addresses the issue of to what extent forest certification schemes contribute to the enhancement of environmental protection in Swedish forestry. Our assessment is built on the analysis of three different data sets, namely: 1) the Swedish National Forest Inventory (NFI), 2) the Swedish Database for Forest Owner Analysis, presenting data on small-scale forestry practices and certification, and 3) a follow-up mail survey addressed to private small-scale forest owners with certified forest properties. Our NFI analysis indicated some minor improvements in forest conditions, corresponding with the interim target for enhanced biological diversity (dead wood, broad-leaved trees and old forests). The improvements were less evident on large-scale forest properties (certified in accordance with the Forest Stewardship Council scheme) than on small-scale private forest properties (mainly certified in accordance with the Programme for the Endorsement of Forest Certification Schemes). This contradicts a common assumption that a much higher degree of certification with stricter environmental standards will give more evident positive impacts on environmental conditions. However, results from the follow-up survey showed that more harvesting activity had taken place on certified small-scale forest properties than on non-certified properties. This could mean more negative effects on biodiversity. We conclude by stressing the importance of improving quantitative methods for determining a cause-and-effect relationship between certification and nature protection; previous research tends to report rather far-reaching conclusions based on limited data sets.
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| 37605. |
- Johansson, Jarkko, et al.
(author)
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Cerebrovascular integrity affects gradients of aging-related dopamine D1 differences in the striatum
- 2023
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In: Aging Brain. - : Elsevier. - 2589-9589. ; 4
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Journal article (peer-reviewed)abstract
- Extant research suggest aging-related losses of different dopaminergic markers, including presynaptic dopamine transporters as well as post-synaptic DA receptors. Given the central role of DA in neurocognitive functions, maintenance of a healthy DA system may be a key to mitigate age-related cognitive decline. Mechanisms behind DA losses in aging are however largely uncharted. Past research documented an association between dopaminergic integrity and cerebrovascular health (via white matter lesion volumes). However, it remains unclear whether proximity to lesions affected the spatial patterns of age-related D1DR differences within the striatum, and whether such differences are related to mnemonic function. Here, a large cohort of middle-aged to older healthy participants (age = 40–80 years, n = 119, 50 % women) was assessed for D1-receptor (D1DR) availability with positron emission tomography using [11C]SCH23390, and for white matter lesions using FLAIR-MRI. We found evidence for variations in degree of age-related differences along the ventro-dorsal axis, with more pronounced differences in the dorsal caudate. Further analyses revealed an association between distance to lesions and extent of D1DR losses in the caudate. Furthermore, D1DR differences in dorsal caudate (proximal to lesions) was more strongly associated with memory performance. In conclusion, the present findings suggest that maintenance of cerebrovascular health may be a key factor in promoting successful dopaminergic and memory aging.
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| 37606. |
- Johansson, Johanna, 1983-
(author)
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Challenges to the Legitimacy of Private Forest Governance : the Development of Forest Certification in Sweden
- 2012
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In: Environmental Policy and Governance. - : John Wiley & Sons. - 1756-932X .- 1756-9338. ; 22:6, s. 424-436
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Journal article (peer-reviewed)abstract
- Substantial scholarly attention has been given to the effectiveness and legitimacy of private forest governance, especially the Forest Stewardship Council (FSC). Research has suggested that such cooperation between forest corporations and ENGOs may develop shared norms for responsible forestry. At least initially, however, conflicts are likely to occur since these stakeholders are accountable to different constituencies.Yet there are comparatively few studies on how such conflicts have affected the development and legitimacy of forest certification on the national level, which is where conflicts must be managed. This study explores how stakeholders’ search for accountability has influenced the legitimacy of forest certification schemes, drawing on developments in Sweden. The study relies on the theoretical foundations of governance, legitimacy and accountability, and on reports from forest corporations and ENGOs. The results show that these stakeholders have continuously disagreed on the input and output legitimacy of forest certification, though the positions have changed over time, eventually making ENGOs reject forest certification schemes. These repeated conflicts have been fuelled by the stakeholders’ search for public reputational accountability and market accountability. In effect, the very meaning of the FSC label is today being questioned. Thereby forest certification in Sweden has, at least temporarily, left the suggested path to the evolution of shared norms. These results call for related studies on how to manage accountability issues and power relations in forest certification.
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| 37607. |
- Johansson, Johanna, 1983-
(author)
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Constructing and contesting the legitimacy of private forest governance : The case of forest certification in Sweden
- 2013
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Doctoral thesis (other academic/artistic)abstract
- In recent decades, political scientists have devoted substantial attention to the changing role of the state towards more inclusion of non-state actors in policymaking. This deliberative turn, or move towards governance, may signal inability to handle complex problems without cooperation with nonstate actors. On the other hand, governance is frequently credited with generating legitimate decision-making processes and results. In some instances, non-governmental actors have even taken the lead in policymaking. One archetype of such private governance, which has received significant scholarly attention, is forest certification. The Forest Stewardship Council (FSC) is frequently described as the most democratic and therefore legitimate forest certification organization since it grants equal voting rights to three stakeholder groups in the formulation of criteria for responsible forestry: environmental non-governmental organizations (ENGOs), social groups (indigenous peoples and labor organizations) and forest owners. However, in Sweden, a country often described as a role model in forest certification, the FSC has increasingly received critique for failing to generate legitimate processes and results, and recently three of five ENGOs have chosen to exit the FSC organization. Such processes of de-legitimation have received little attention in the forest certification literature.This thesis therefore provides a critical assessment of the legitimacy of forest certification in Sweden. Legitimacy is analyzed through concerned stakeholders’ perceptions of both procedural qualities (input legitimacy) and problem-solving capacity (output legitimacy). This study of legitimacy is combined with an assessment of the ability of certification to enhance environmental protection, defined as changes in both forest management practices and biophysical conditions. The thesis focuses not the least on legitimacy on the local level, which is where the actual implementation takes place. Today local studies of the legitimacy of forest certification are rare.Both quantitative and qualitative research methods are applied and a number of sources are analyzed: forest monitoring data, survey data, interviews with and documents produced by the participating stakeholders. Papers I and IV analyze the perceived legitimacy of forest certification, while Papers II and III analyze forest certification schemes’ ability to enhance environmental protection.The results show that a process of de-legitimation is occurring in Swedish forest certification. In particular, certification has lost legitimacy with ENGOs, which increasingly consider Swedish forest certification to lack both input legitimacy and output legitimacy. Moreover, although the Swedish FSC standard pays attention to reindeer husbandry, the results show that reindeer herders consider themselves to have limited power to influence long-term forest planning and management (low output legitimacy). The forest industry, on the other hand, increasingly grants legitimacy to forest certification due to customer demands, which are created not the least by pressures from international ENGOs and by EU regulation. The results also show that Swedish forest companies have paid more attention to their environmental practices after obtaining certification. However, to what extent these changes result in positive environmental impacts remains uncertain, especially since forests in Sweden grow slowly, which requires analyses over time. There are also measurement problems resulting from the low certification rate among small-scale forest owners and from the fact that certified small-scale owners tend to be more active in their management.These findings highlight that research on private forest governance should not neglect the role of the state, neither as a buyer nor as a regulator. These findings also suggest that further research should pay attention to power asymmetries in private governance and develop methods for better understanding and evaluating the certification schemes’ environmental and social impacts.
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| 37608. |
- Johansson, Johanna, 1983-, et al.
(author)
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Coordinating and implementing multiple systems for forest management : implications of the regulatory framework for sustainable forestry in Sweden
- 2014
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In: Journal of Natural Resources Policy Research. - : Taylor & Francis. - 1939-0459 .- 1939-0467. ; 6:2-3, s. 117-133
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Journal article (peer-reviewed)abstract
- The complexity of multi-level governance is well illustrated by forest management in one of Europe’s large forested states, Sweden. Deregulated government policies emphasise “freedom with responsibility,” largely expecting the forest sector to determine ways in which policy goals and legal requirements are reached. In relation to this, Sweden has become one of the countries with the largest share of forests certified by third-party organisations, such as the Forest Stewardship Council (FSC), in accordance with specific environmental and social criteria. This multi-level case study draws on official documents and semi-structured interviews to analyse Swedish forest governance; specifically, the impact of multiplicity and complexity of environmental considerations on agreement over goal coordination, implementation, and evaluation for feedback and accountability. This contributes to previous research by analysing interactions between state regulation and certification at multiple levels.
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| 37609. |
- Johansson, Johannes D., 1977-, et al.
(author)
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Combined diffuse light reflectance and electric impedance measurements for navigation aid in deep brain surgery
- 2009
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In: Stereotactic and Functional Neurosurgery. - Basel : S. Karger AG. - 1011-6125 .- 1423-0372. ; 87:2, s. 105-113
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Journal article (peer-reviewed)abstract
- Aim: The aim of this study is to investigate reflected light intensity combined with impedance for navigation aid during stereotactic neurosurgery.Methods: During creation of 21 trajectories for stereotactic implantation of deep brain stimulation electrodes in the globus pallidus internus or subthalamus (zona incerta or subthalamic nucleus), impedance at 512 kHz and reflected light intensity at 780 nm were measured continuously and simultaneously with a radio frequency electrode containing optical fibres. The signals were compared with anatomy determined from pre- and postoperative MRI and CT. The measurements were performed within minutes and signal analysis was done post-operatively.Results: Reflected light intensity was low from cortex, lateral ventricle, caudate nucleus and putamen. It was intermediate from globus pallidus and thalamus while it was high from subcortical white matter, internal capsule and the subthalamus. The electric impedance was less consistent but generally low in the cortex, intermediate in subcortical white matter, the putamen, the globus pallidus and the thalamus and high in the internal capsule and the subthalamus.Conclusion: Reflected light intensity and electric impedance give complementary information about passed tissue and the combination seems promising for navigation aid during stereotactic neurosurgery.
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| 37610. |
- Johansson, Joakim, et al.
(author)
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Dynamics of leukocyte receptors after severe burns: An exploratory study
- 2011
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In: BURNS. - Oxford : Elsevier Science B.V., Amsterdam.. - 0305-4179 .- 1879-1409. ; 37:2, s. 227-233
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Journal article (peer-reviewed)abstract
- Background: Patients with burns are susceptible to organ failure, and there is indirect evidence that leukocytes may contribute to this process. They may change the expression of cell-surface receptors after certain stimuli, for example, the burn. We therefore aimed to assess the changes induced by the burn in the expression of leukocyte cell-surface receptors CD11b, CD14, CD16, and CD62L on the surface of PMNs and monocytes. We also wanted to examine the dynamics of this activation during the first week after the burn, and to relate it to the size of the injury. Methods: Ten patients with burns of andgt;15% (TBSA) were included in the study. Blood samples were collected on arrival and every consecutive morning during the first week. Healthy volunteers acted as controls. Results: PMN CD11b expression was increased. The extent of PMN CD11b expression correlated negatively to the size of the full thickness burn. Monocyte CD14 expression increased initially but there was no relation to the size of the burn. PMN CD16 expression decreased initially during the first days and the decrease was related to burn size. CD62L did not vary depending on the burn in either PMN or monocytes during the first week after the burn. Conclusion: This study showed that specific receptors on the surface of leukocytes (PMN CD11b, monocyte CD14 and PMN CD16) are affected by the burn. Expression of PMN CD11b and CD16 are related to burn size. Burn-induced effects on the expression of PMN receptors, such as PMN CD11b and CD16, may contribute to burn-induced infection susceptibility.
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