1. |
- Carlbring, Per, 1972-, et al.
(författare)
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Applied relaxation : an experimental analogue study of therapist vs. computer administration
- 2007
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Ingår i: Computers in human behavior. - : Elsevier BV. - 0747-5632 .- 1873-7692. ; 23:1, s. 2-10
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Tidskriftsartikel (refereegranskat)abstract
- This experimental analog component study compared two ways of administrating relaxation, either via a computer or by a therapist. The second phase of applied relaxation was used, which is called "release-only relaxation". Sixty participants from a student population were randomized to one of three groups: computer-administered relaxation, therapist-administered relaxation, or a control group in which participants surfed on the Internet. Outcome was measures using psycho-physiological responses and self-report. Objective psychophysiological data and results on the subjective visual analogue scale suggest that there was no difference between the two forms of administration. Both experimental groups became significantly more relaxed than the control group that surfed on the Internet. Practical applications and future directions are discussed.
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2. |
- Kirilovas, Dmitrijus, et al.
(författare)
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Granulosa cell aromatase enzyme activity : Effects of follicular fluid from patients with polycystic ovary syndrome, using aromatase conversion and [11C]vorozole-binding assays
- 2006
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Ingår i: Gynecological Endocrinology. - : Informa UK Limited. - 0951-3590 .- 1473-0766. ; 22:12, s. 685-691
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Tidskriftsartikel (refereegranskat)abstract
- The local regulation of ovarian aromatase enzyme in polycystic ovary syndrome (PCOS) was studied with aromatase conversion and [C-11]vorozole-binding assays to analyze aromatase activity, substrate-enzyme affinity and number of aromatase binding sites in non-cultured human granulosa cells (GC) incubated with different sources and preparations of follicular fluid (FF). Incubation with FF from women stimulated in in vitro fertilization cycles with follicle-stimulating hormone yielded higher conversion activity than with FF from healthy women and PCOS patients, paralleled with higher substrate affinity (lower K-d) than with FF from healthy women. In PCOS women, charcoal-pretreated FF yielded higher conversion, whereas the ether-pretreated FF yielded lower conversion activity, than with untreated PCOS FF. Both preparations of FF yielded higher affinity to substrate (lower Kd values) and the ether-pretreated FF a lower number of binding sites (B-max). It seems that steroids with the presence of proteins in PCOS FF reduced aromatase conversion activity through decreased substrate affinity, whereas FF preparations devoid of proteins reduced the aromatase conversion activity mainly through blocking of aromatase active sites. Identification of specific agents responsible for this rapid regulation of aromatase function might help to understand normal regulation of the menstrual cycle and supposed imbalances of inhibitors/activators in PCOS.
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3. |
- Uhlén, Mathias, et al.
(författare)
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A human protein atlas for normal and cancer tissues based on antibody proteomics
- 2005
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Ingår i: Molecular & Cellular Proteomics. - 1535-9476 .- 1535-9484. ; 4:12, s. 1920-1932
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Tidskriftsartikel (refereegranskat)abstract
- Antibody-based proteomics provides a powerful approach for the functional study of the human proteome involving the systematic generation of protein-specific affinity reagents. We used this strategy to construct a comprehensive, antibody-based protein atlas for expression and localization profiles in 48 normal human tissues and 20 different cancers. Here we report a new publicly available database containing, in the first version, similar to 400,000 high resolution images corresponding to more than 700 antibodies toward human proteins. Each image has been annotated by a certified pathologist to provide a knowledge base for functional studies and to allow queries about protein profiles in normal and disease tissues. Our results suggest it should be possible to extend this analysis to the majority of all human proteins thus providing a valuable tool for medical and biological research.
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4. |
- Andersson, Irene, 1978, et al.
(författare)
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Endothelial dysfunction in growth hormone transgenic mice
- 2006
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Ingår i: Clinical Science. - 0143-5221 .- 1470-8736. ; 110:2, s. 217-25
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Tidskriftsartikel (refereegranskat)abstract
- Acromegaly [overproduction of GH (growth hormone)] is associated with cardiovascular disease. Transgenic mice overexpressing bGH (bovine GH) develop hypertension and hypercholesterolaemia and could be a model for cardiovascular disease in acromegaly. The aims of the present study were to investigate the effects of excess GH on vascular function and to test whether oxidative stress affects endothelial function in bGH transgenic mice. We studied the ACh (acetylcholine)-induced relaxation response in aortic and carotid rings of young (9-11 weeks) and aged (22-24 weeks) female bGH transgenic mice and littermate control mice, without and with the addition of a free radical scavenger {MnTBAP [Mn(III)tetrakis(4-benzoic acid)porphyrin chloride]}. We also measured mRNA levels of eNOS (endothelial nitric oxide synthase) and EC-SOD (extracellular superoxide dismutase). Intracellular superoxide anion production in the vascular wall was estimated using a dihydroethidium probe. Carotid arteries from bGH transgenic mice had an impaired ACh-induced relaxation response (young, 46 +/- 7% compared with 69 +/- 8%; aged, 52 +/- 5% compared with 80 +/- 3%; P < 0.05), whereas endothelial function in aorta was intact in young but impaired in aged bGH transgenic mice. Endothelial dysfunction was corrected by addition of MnTBAP in carotid arteries from young mice and in aortas from aged mice; however, MnTBAP did not correct endothelial dysfunction in carotid arteries from aged bGH transgenic mice. There was no difference in intracellular superoxide anion production between bGH transgenic mice and control mice, whereas mRNA expression of EC-SOD and eNOS was increased in aortas from young bGH transgenic mice compared with control mice (P < 0.05). We interpret these data to suggest that bGH overexpression is associated with a time- and vessel-specific deterioration in endothelial function, initially caused by increased oxidative stress and later by other alterations in vascular function.
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5. |
- Andersson, Irene, 1978, et al.
(författare)
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Increased atherosclerotic lesion area in apoE deficient mice overexpressing bovine growth hormone
- 2006
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Ingår i: Atherosclerosis. - : Elsevier BV. - 0021-9150. ; 188:2, s. 331-40
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Tidskriftsartikel (refereegranskat)abstract
- Human growth hormone (GH) excess is linked to increased cardiovascular morbidity and mortality. However, little is known about the effect of GH excess on atherosclerosis. We developed a new mouse model to assess the hypothesis that GH overexpression accelerates atherosclerotic lesion formation. apoE(-/-) mice were crossed with bovine GH (bGH) transgenic mice to yield apoE(-/-) mice overexpressing bGH (apoE(-/-)/bGH). The mice were fed either standard or Western diet. At 22 weeks, atherosclerotic lesion area of thoracic aorta was larger in apoE(-/-)/bGH mice compared with littermate apoE(-/-) mice fed either diet (standard: +161+/-50%, Western: +430+/-134%). Aortic sinus lesions were more severe in apoE(-/-)/bGH mice fed standard diet compared with littermate apoE(-/-) mice. apoE(-/-)/bGH mice had lower (VLDL+LDL)/HDL ratios compared with littermate apoE(-/-) mice, while systolic blood pressure was higher in apoE(-/-)/bGH mice, irrespective of diet. The levels of serum amyloid A and hepatic CRP mRNA were higher in apoE(-/-)/bGH mice than in littermate apoE(-/-) mice. In conclusion, this study shows that excess GH augments the development of atherosclerosis in apoE(-/-) mice. The mechanisms could be direct effects of GH on cellular processes in the vessel wall or the result of concomitant processes such as hypertension or a general inflammatory state.
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6. |
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7. |
- Andren, Peter, et al.
(författare)
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FUD rörande gång- och cykelvägar : en beskrivning av VTI:s kompetens och resurser
- 2006
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The present report presents, partly, the collected VTI research on the "functional properties" of pedestrian and bicycle roads, and partly a survey of what has been done in this field outside of VTI. The term "functional property" has been interpreted in a broad sense, and basically everything connected with bicycle roads and bicycle traffic is included in the VTI literature review, which is the major part of the report. The operating environment analysis is made on the basis of the discussions from a seminar held at VTI, December 12, 2005, and complemented with literature reviews. The possibilities to build an instrumented vehicle for measuring bicycle roads, and the relevant properties of an evenness index, were discussed at the seminar. In the literature review, the research of VTI has been divided into five parts: traffic safety, maintenance and operation, mode choice, measurement of cycle flow, and the umbrella part "others". The research concerning traffic safety dominates, both at VTI and elsewhere. One of the conclusions from the project is that VTI should try to get funding to develop a measuring vehicle for cycleway surfaces. There is also a need to develop the unreliable methods used today (elastic tube and induction coil) to count bicycle traffic.
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8. |
- Andresen Bergström, Moa, 1978, et al.
(författare)
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A skin-like cytochrome P450 cocktail activates prohaptens to contact allergenic metabolites.
- 2007
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Ingår i: The Journal of investigative dermatology. - : Elsevier BV. - 1523-1747 .- 0022-202X. ; 127:5, s. 1145-53
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Tidskriftsartikel (refereegranskat)abstract
- Allergic contact dermatitis is a complex syndrome representing immunological responses to cutaneous exposure to protein-reactive chemicals. Although many contact sensitizers directly can elicit this disorder, others (prohaptens) require activation. Knowledge regarding the activating mechanisms remains limited, but one possibility is metabolic activation by cytochrome P450 (CYP) enzymes in the skin. We have, after quantitative reverse transcriptase-PCR studies of the CYP content in 18 human skin samples, developed an enriched skin-like recombinant human (rh) CYP cocktail using CYP1A1, 1B1, 2B6, 2E1, and 3A5. To validate the rhCYP cocktail, a prohaptenic conjugated diene ((5R)-5-isopropenyl-2-methyl-1-methylene-2-cyclohexene) was investigated using: the skin-like rhCYP cocktail, a liver-like rhCYP cocktail, single rhCYP enzymes, liver microsomes, keratinocytes, and a dendritic cell (DC) assay. The diene was activated to sensitizing epoxides in all non-cell-based incubations including the skin-like rhCYP cocktail. An exocyclic epoxide metabolite ((7R)-7-isopropenyl-4-methyl-1-oxaspiro[2.5]oct-4-ene) was found to be mainly responsible for the allergenic activity of the diene. This epoxide also induced pronounced DC activation indicated by upregulation of IL-8. The skin-like rhCYP cocktail provides a simplified alternative to using skin tissue preparations in mechanistic studies of CYP-mediated skin metabolism of prohaptens and offers the future possibility of designing in vitro predictive assays for assessment of allergenic activity of prohaptens.
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9. |
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10. |
- Bergström, Anna
(författare)
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Variation in car accident risk during winter
- 2006
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Rapport (populärvet., debatt m.m.)abstract
- At the beginning and end of a winter season, there is a greater risk of car accidents in ice and snow conditions than during mid-winter. This was found in this Swedish study where accident data for four winters was correlated to road condition data obtained through visual observations. The purpose of the study was to see how the car accident risk on ice and snow varies over the winter. To examine this, the winter season was divided into three periods: Early winter, Mid-winter, and Late winter. Accident rates were calculated for each period and the values for Early and Late winter were compared with the corresponding Mid-winter values. The accident rate (car accident risk) is here defined as the number of accidents divided by the vehicle mileage, where the accident data includes all the car accidents on Swedish state roads recorded by the police, during the winter seasons from 1993/94 through 1996/97, excluding collisions with wildlife. Accident rates were calculated for five different types of road condition assessed by the police: Dry bare ground, Moist or Wet bare ground, Packed snow or Thick ice, Black ice or Hoar-frost, and Loose snow or Slush, where the last three are ice and snow conditions. The vehicle mileage for each road condition was calculated on the basis of visual observations performed to monitor the road condition. The analyses show that icy and snowy road conditions constitute a greater risk during Early and Late winter periods than during Mid-winter. The reason for this could be that drivers are more likely to expect these kinds of road condition during Mid-winter than at the beginning and end of the winter season. Moreover, the accident risk is greater during Late winter than during Early winter, and the shorter the Early and Late winter period, the higher the risk.
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11. |
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12. |
- Bergström, Carl Fredrik, 1965-, et al.
(författare)
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Lissabonfördraget
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)
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13. |
- Bergström, J., et al.
(författare)
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Symbiots: Conceptual interventions into energy systems
- 2009. - 10
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Ingår i: Proceedings of NORDES.
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Konferensbidrag (refereegranskat)abstract
- Symbiots set out to examine values such as ease-of-use, comfort, and rationality assumed within conventions of ‘good design’, in order to expose issues related to energy consumption and current human- (versus eco-) centered design paradigms. Exploring re-interpretations of graphical patterns, architectural configurations and electrical infrastructure typical in Swedish cities, Symbiots takes the form of a photo series in the genre of contemporary hyper-real art photography. Painting a vivid picture of alternatives to current local priorities around energy consumption, the three design concepts depicted are strangely familiar, alternatively humorous and sinister.
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14. |
- Bergström, Kerstin, 1945, et al.
(författare)
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Hållbar utveckling i matsystemet
- 2007
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Ingår i: Hushållsvetenskap & Co. - Göteborg : Göteborg University. ; , s. 65-74
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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15. |
- Bergström, Lena, et al.
(författare)
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Kustfisk och Fiske : Analyser av tillståndet hos abborre, gädda, gös, piggvar, sik, siklöja och skrubbskädda år 2005
- 2006
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I denna internrapport redovisas de analyser som utgjort underlag till Kustlaboratoriets bidragtill Fiskeriverkets gemensamma resurs- och miljööversikt år 2006. Analyserna häri byggerpå loggboksdata, provfi ske, journalföringsdata, samt i vissa fall även omgivningsdata, ochomfattar abborre, gädda, gös, piggvar, sik, siklöja och skrubbskädda. Syftet har varit attdokumentera analyserna för spridning inom laboratoriet, och de tillhörande texterna är därförkortfattade. Vidare information kan fås av Ann-Britt Florin, Kerstin Söderberg, Lena Bergströmeller Anna Gårdmark, som genomförde analyserna.
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16. |
- Bergström, L., et al.
(författare)
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Signals of WIMP annihilation into electrons at the galactic center
- 2005
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Ingår i: Proceedings of the 29th International Cosmic Ray Conference, Vol 4: OG 2.1, 2.2 & 2.3. - : Tata Institute of Fundamental Research. ; , s. 57-60
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Konferensbidrag (refereegranskat)abstract
- Photons from the annihilation of dark matter in the center of our Galaxy are expected to provide a promising way to find out the nature and distribution of the dark matter itself. These photons can be either produced directly and/or through successive decays of annihilation products, or radiated from electrons and positrons. This ends up in a multi-wavelength production of photons whose expected intensity can be compared to observational data. Assuming that the Lightest Supersymmetric Particle makes the dark matter, we derive the expected photon signal from a given dark matter model and compare it with present available data.
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17. |
- Birgner, Carolina, et al.
(författare)
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Altered extracellular levels of DOPAC and HVA in the rat nucleus accumbens shell in response to sub-chronic nandrolone administration and a subsequent amphetamine challenge
- 2007
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Ingår i: Neuroscience Letters. - : Elsevier BV. - 0304-3940 .- 1872-7972. ; 412:2, s. 168-172
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Tidskriftsartikel (refereegranskat)abstract
- Associated with acts of violence and polydrug use, abuse of anabolic androgenic steroids (AAS) is an increasing problem in society. The aim of the present study was to elucidate whether sub-chronic treatment with the AAS nandrolone decanoate affects dopamine release and dopamine metabolism in the rat nucleus accumbens shell, before and after an amphetamine challenge. Male Sprague–Dawley rats received daily i.m. injections of nandrolone decanoate (15 mg/kg) or vehicle for 14 days. On day 15, the animals were anaesthetized and a microdialysis probe was implanted into the nucleus accumbens shell. Extracellular fluid was collected 1 h before and 3 h after a single amphetamine injection (5 mg/kg). The samples were then analyzed regarding the content of dopamine, and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), using HPLC with electrochemical detection. Two weeks of nandrolone decanoate administration caused a significant decrease of the basal DOPAC and HVA levels, which remained low during the first hour following the amphetamine challenge. Dopamine levels did not differ significantly between groups, neither after the nandrolone pre-treatment nor the amphetamine challenge. In conclusion, these novel findings indicate that AAS alter the metabolism of dopamine in a brain region involved in the development of drug dependence.
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18. |
- Birgner, Carolina, 1978-
(författare)
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Anabolic androgenic steroids and central monoaminergic systems : Supratherapeutic doses of nandrolone decanoate affect dopamine and serotonin
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Supratherapeutic doses of anabolic androgenic steroids (AASs) are administered, not only as performance-enhancing drugs in the world of sports, but also in order to modify behaviour. AAS abusers are at risk of developing serious physical and psychological side effects such as dependence and aggressive behaviour. The aim of this thesis was to investigate the impact of supratherapeutic doses of nandrolone decanoate after subchronic administration on dopamine and serotonin pathways involved in drug dependence and aggression, in the male rat brain.Adult male Sprague-Dawley rats received intramuscular injections of nandrolone decanoate (3 or 15 mg/kg) or vehicle once daily for 14 days. Nandrolone decanoate pre-exposure abolished the effect of amphetamine on the 3,4-dihydroxyphenylacetic acid (DOPAC) tissue level in the hypothalamus and on the DOPAC/dopamine ratio in the hypothalamus and the hippocampus. A significant decrease of the basal extracellular DOPAC and homovanillic acid (HVA) levels could be detected in the nucleus accumbens, which remained low during the first hour following the amphetamine challenge. Nandrolone decanoate significantly reduced the activity of both monoamine oxidase A and B (MAO-A and -B) in the caudate putamen and amygdala. The gene transcript levels of MAO-B, and the dopamine D1 and D4 receptors were altered in limbic regions. No changes in transcriptional levels could be detected among the serotonin receptor genes examined. However, the density of the serotonin transporter protein was elevated in a range of aggression-related brain regions.Taken together, subchronic administration of nandrolone decanoate causes dopaminergic and serotonergic dysregulations in distinct brain regions. These areas of the brain are involved in the development of drug dependence and expression of impulsive and aggressive behaviours. These results may contribute to explain some of the behavioural changes often reported in AAS abusers, such as polydrug use and impaired impulse control.
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19. |
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20. |
- Birgner, Carolina, et al.
(författare)
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Reduced activity of monoamine oxidase in the rat brain following repeated nandrolone decanoate administration
- 2008
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Ingår i: Brain Research. - : Elsevier BV. - 0006-8993 .- 1872-6240. ; 1219, s. 103-110
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Tidskriftsartikel (refereegranskat)abstract
- Anabolic androgenic steroids (AAS) are known as doping agents within sports and body-building, but are currently also abused by other groups in society in order to promote increased courage and aggression. We previously showed that 14 days of daily intramuscular injections of the AAS nandrolone decanoate (15 mg/kg) reduced the extracellular levels of the dopaminergic metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the nucleus accumbens shell using microdialysis. The aim of the present study was to investigate whether the same dose regimen of nandrolone decanoate may affect the activities of the dopamine-metabolizing enzymes monoamine oxidases A and B (MAO-A and MAO-B). A radiometric assay was used to determine the activities of MAO-A and MAO-B in rat brain tissues after 14 days of daily i.m. nandrolone decanoate injections at the doses 3 and 15 mg/kg. Gene transcript contents of MAO-A, MAO-B and cathecol-O-methyltransferase (COMT) were measured with quantitative real-time reverse transcription PCR. 3 mg/kg of nandrolone decanoate significantly reduced the activity of both MAO-A and -B in the caudate putamen. 15 mg/kg of nandrolone decanoate significantly reduced the activity of MAO-A in the amygdala and increased the gene transcript level of MAO-B in the substantia nigra. In conclusion, imbalanced MAO activities may contribute to explain the impulsive and aggressive behaviour often described in AAS abusers. The reduced MAO activities observed are in line with our previously presented findings of decreased extracellular levels of DOPAC and HVA in the rat brain, indicating decreased monoaminergic activity following repeated AAS administration.
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21. |
- Birgner, Carolina, et al.
(författare)
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The anabolic androgenic steroid nandrolone decanoate affects mRNA expression of dopaminergic but not serotonergic receptors
- 2008
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Ingår i: Brain Research. - : Elsevier BV. - 0006-8993 .- 1872-6240. ; 1240, s. 221-228
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Tidskriftsartikel (refereegranskat)abstract
- The abuse of anabolic androgenic steroids (AASs) at supratherapeutic doses is a problem not only in the world of sports, but also among non-athletes using AASs to improve physical appearance and to become more bold and courageous. Investigations of the possible neurochemical effects of AAS have focused partially on the monoaminergic systems, which are involved in aggressive behaviours and the development of drug dependence. In the present study, we administered nandrolone decanoate (3 or 15 mg/kg/day for 14 days) and measured mRNA expression of dopaminergic and serotonergic receptors, transporters and enzymes in the male rat brain using quantitative real-time polymerase chain reaction. Expression of the dopamine D1-receptor transcript was elevated in the amygdala and decreased in the hippocampus while the transcript level of the dopamine D4-receptor was increased in the nucleus accumbens. No changes in transcriptional levels were detected among the serotonin-related genes examined in this study. The altered mRNA expression of the dopamine receptors may contribute to some of the behavioural changes often reported in AAS abusers of increased impulsivity, aggression and drug-seeking.
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22. |
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23. |
- Egecioglu, Emil, 1977, et al.
(författare)
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Growth hormone receptor deficiency in mice results in reduced systolic blood pressure and plasma renin, increased aortic eNOS expression, and altered cardiovascular structure and function
- 2007
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Ingår i: AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 292:5
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Tidskriftsartikel (refereegranskat)abstract
- To study the role of the growth hormone receptor (GHR) in the development of cardiovascular structure and function, female GHR gene-disrupted or knockout (KO) and wild-type (WT) mice at age 18 wk were used. GHR KO mice had lower plasma renin levels (12 ± 2 vs. 20 ± 4 mGU/ml, P < 0.05) and increased aortic endothelial NO synthase (eNOS) expression (146%, P < 0.05) accompanied by a 25% reduction in systolic blood pressure (BP, 110 ± 4 vs. 147 ± 3 mmHg, P < 0.001) compared with WT mice. Aldosterone levels were unchanged, whereas the plasma potassium concentration was elevated by 14% ( P < 0.05) in GHR KO. Relative left ventricular weight was 14% lower in GHR KO mice ( P < 0.05), and cardiac dimensions as analyzed by echocardiography were similarly reduced. Myograph studies revealed a reduced maximum contractile response in the aorta to norepinephrine (NE) and K+ ( P < 0.05), and aorta media thickness was decreased in GHR KO ( P < 0.05). However, contractile force was normal in mesenteric arteries, whereas sensitivity to NE was increased ( P < 0.05). Maximal acetylcholine-mediated dilatation was similar in WT and GHR KO mice, whereas the aorta of GHR KO mice showed an increased sensitivity to acetylcholine ( P < 0.05). In conclusion, loss of GHR leads to low BP and decreased levels of renin in plasma as well as increase in aortic eNOS expression. Furthermore, GHR deficiency causes functional and morphological changes in both heart and vasculature that are beyond the observed alterations in body size. These data suggest an important role for an intact GH/IGF-I axis in the maintenance of a normal cardiovascular system.
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24. |
- Egecioglu, Emil, 1977, et al.
(författare)
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Growth hormone receptor deficiency results in blunted ghrelin feeding response, obesity, and hypolipidemia in mice.
- 2006
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Ingår i: American journal of physiology. Endocrinology and metabolism. - : American Physiological Society. - 0193-1849 .- 1522-1555. ; 290:2
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Tidskriftsartikel (refereegranskat)abstract
- We have previously shown that growth hormone (GH) overexpression in the brain increased food intake, accompanied with increased hypothalamic agouti-related protein (AgRP) expression. Ghrelin, which stimulates both appetite and GH secretion, was injected intracerebroventricularly to GHR-/- and littermate control (+/+) mice to determine whether ghrelin's acute effects on appetite are dependent on GHR signaling. GHR-/- mice were also analyzed with respect to serum levels of lipoproteins, apolipoprotein (apo)B, leptin, glucose, and insulin as well as body composition. Central injection of ghrelin into the third dorsal ventricle increased food consumption in +/+ mice, whereas no change was observed in GHR-/- mice. After ghrelin injection, AgRP mRNA expression in the hypothalamus was higher in +/+ littermates than in GHR-/- mice, indicating a possible importance of AgRP in the GHR-mediated effect of ghrelin. Compared with controls, GHR-/- mice had increased food intake, leptin levels, and total and intra-abdominal fat mass per body weight and deceased lean mass. Moreover, serum levels of triglycerides, LDL and HDL cholesterol, and apoB, as well as glucose and insulin levels were lower in the GHR-/- mice. In summary, ghrelin's acute central action to increase food intake requires functionally intact GHR signaling. Long-term GHR deficiency in mice is associated with high plasma leptin levels, obesity, and increased food intake but a marked decrease in all lipoprotein fractions.
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25. |
- Ekerfelt, Christina, 1957-, et al.
(författare)
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Mercury exposure as a model for deviation of cytokine responses in experimental Lyme arthritis : HgCl2 treatment decreases T helper cell type 1-like responses and arthritis severity but delays eradication of Borrelia burgdorferi in C3H/HeN mice
- 2007
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Ingår i: Clinical and Experimental Immunology. - : Oxford University Press (OUP). - 0009-9104 .- 1365-2249. ; 150:1, s. 189-197
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Tidskriftsartikel (refereegranskat)abstract
- Lyme borreliosis is a complex infection, where some individuals develop so-called ‘chronic borreliosis’. The pathogenetic mechanisms are unknown, but the type of immune response is probably important for healing. A strong T helper cell type 1 (Th1)-like response has been suggested as crucial for eradication of Borrelia and for avoiding development of chronic disease. Many studies aimed at altering the Th1/Th2 balance in Lyme arthritis employed mice deficient in cytokine genes, but the outcome has not been clear-cut, due possibly to the high redundancy of cytokines. This study aimed at studying the importance of the Th1/Th2 balance in murine Borrelia arthritis by using the Th2-deviating effect of subtoxic doses of inorganic mercury. Ninety-eight C3H/HeN mice were divided into four groups: Borrelia-infected (Bb), Borrelia-infected exposed to HgCl2 (BbHg), controls exposed to HgCl2 alone and normal controls. Mice were killed on days 3, 16, 44 and 65 post-Borrelia inoculation. Arthritis severity was evaluated by histology, spirochaetal load determined by Borrelia culture, IgG2a- and IgE-levels analysed by enzyme-linked immunosorbemt assay (ELISA) and cytokine-secreting cells detected by enzyme-linked immunospot (ELISPOT). BbHg mice showed less severe histological arthritis, but delayed eradication of spirochaetes compared to Bb mice, associated with increased levels of IgE (Th2-induced) and decreased levels of IgG2a (Th1-induced), consistent with a Th2-deviation. Both the numbers of Th1 and Th2 cytokine-secreting cells were reduced in BbHg mice, possibly explained by the fact that numbers of cytokine-secreting cells do not correlate with cytokine concentration. In conclusion, this study supports the hypothesis that a Th1-like response is required for optimal eradication of Borrelia.
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