1. |
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2. |
- Kehoe, Laura, et al.
(författare)
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Make EU trade with Brazil sustainable
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341-
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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3. |
- Lai, En Yin, et al.
(författare)
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Adenosine restores angiotensin II-induced contractions by receptor-independent enhancement of calcium sensitivity in renal arterioles
- 2006
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Ingår i: Circulation Research. - 0009-7330 .- 1524-4571. ; 99:10, s. 1117-1124
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Tidskriftsartikel (refereegranskat)abstract
- Adenosine is coupled to energy metabolism and regulates tissue blood flow by modulating vascular resistance. In this study, we investigated isolated, perfused afferent arterioles of mice, which were subjected to desensitization during repeated applications of angiotensin II. Exogenously applied adenosine restores angiotensin II-induced contractions by increasing calcium sensitivity of the arterioles, along with augmented phosphorylation of the regulatory unit of the myosin light chain. Adenosine restores angiotensin II-induced contractions via intracellular action, because inhibition of adenosine receptors do not prevent restoration, but inhibition of NBTI sensitive adenosine transporters does. Restoration was prevented by inhibition of Rho-kinase, protein kinase C, and the p38 mitogen-activated protein kinase, which modulate myosin light chain phosphorylation and thus calcium sensitivity in the smooth muscle. Furthermore, adenosine application increased the intracellular ATP concentration in LuciHEK cells. The results of the study suggest that restoration of the angiotensin II-induced contraction by adenosine is attributable to the increase of the calcium sensitivity by phosphorylation of the myosin light chain. This can be an important component of vascular control during ischemic and hypoxic conditions. Additionally, this mechanism may contribute to the mediation of the tubuloglomerular feedback by adenosine in the juxtaglomerular apparatus of the kidney.
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4. |
- Lai, En Yin, et al.
(författare)
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Contribution of adenosine receptors in the control of arteriolar tone and adenosine-angiotensin II interaction
- 2006
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Ingår i: Kidney International. - : Elsevier BV. - 0085-2538 .- 1523-1755. ; 70:4, s. 690-698
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Tidskriftsartikel (refereegranskat)abstract
- Adenosine (Ado) mediates vasoconstriction via A(1)-Ado receptors and vasodilation via A(2)-Ado receptors in the kidney. It interacts with angiotensin II (Ang II), which is important for renal hemodynamics and tubuloglomerular feedback (TGF). The aim was to investigate the function of Ado receptors in the Ado -Ang II interaction in mouse microperfused, afferent arterioles. Ado (10(-11)-10(-4) mol/l) caused a biphasic response: arteriolar diameters were reduced (-7%) at Ado 10(-11)-10(-9) mol/l and returned to control values at higher concentrations. Treatment with Ang II (10(-10) mol/l) transformed the response into a concentration-dependent constriction. N-6-cyclopentyladenosine (A(1)-Ado receptor agonist) reduced diameters (12% at 10(-6) mol/l). Application of CGS21680 (10(-12)-10(-4) mol/l, A(2A) receptor agonist) increased the diameter by 13%. Pretreatment with ZM241385 (A(2A)-Ado receptor antagonist) alone or in combination with MRS1706 (A(2B)-Ado receptor antagonist) resulted in a pure constriction upon Ado, whereas 8-cyclopentyltheophylline (CPT) (A(1)-Ado receptor antagonist) inhibited the constrictor response. Afferent arterioles of mice lacking A(1)-Ado receptor did not show constriction upon Ado. Treatment with Ado (10(-8) mol/l) increased the response upon Ang II, which was blocked by CPT. Ado (10(-5) mol/l) did not influence the Ang II response, but an additional blockade of A(2)-Ado receptors enhanced it. The action of Ado on constrictor A(1)-Ado receptors and dilatory A(2)-Ado receptors modulates the interaction with Ang II. Both directions of Ado-Ang II interaction, which predominantly leads to an amplification of the contractile response, are important for the operation of the TGF.
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5. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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6. |
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7. |
- Uggla, Maria, et al.
(författare)
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Future Swedish 3D City Models : Specifications, Test Data, and Evaluation
- 2023
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Ingår i: ISPRS International Journal of Geo-Information. - : MDPI AG. - 2220-9964. ; 12:2
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Tidskriftsartikel (refereegranskat)abstract
- Three-dimensional city models are increasingly being used for analyses and simulations. To enable such applications, it is necessary to standardise semantically richer city models and, in some cases, to connect the models with external data sources. In this study, we describe the development of a new Swedish specification for 3D city models, denoted as 3CIM, which is a joint effort between the three largest cities in Sweden—Stockholm, Gothenburg, and Malmö. Technically, 3CIM is an extension of the OGC standard CityGML 2.0, implemented as an application domain extension (ADE). The ADE is semantically thin, mainly extending CityGML 2.0 to harmonise with national standards; in contrast, 3CIM is mainly based on linkages to external databases, registers, and operational systems for the semantic part. The current version, 3CIM 1.0, includes various themes, including Bridge, Building, Utility, City Furniture, Transportation, Tunnel, Vegetation, and Water. Three test areas were created with 3CIM data, one in each city. These data were evaluated in several use-cases, including visualisation as well as daylight, noise, and flooding simulations. The conclusion from these use-cases is that the 3CIM data, together with the linked external data sources, allow for the inclusion of the necessary information for the visualisation and simulations, but extract, transform, and load (ETL) processes are required to tailor the input data. The next step is to implement 3CIM within the three cities, which will entail several challenges, as discussed at the end of the paper.
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8. |
- Antonsson, Andreas, et al.
(författare)
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Induction of apoptosis by staurosporine involves the inhibition of expression of the major cell cycle proteins at the G(2)/m checkpoint accompanied by alterations in Erk and Akt kinase activities
- 2009
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Ingår i: Anticancer Research. - : International Institute of Anticancer Research. - 0250-7005 .- 1791-7530. ; 29:8, s. 2893-2898
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Staurosporine is a therapeutic agent that inhibits tumor cell growth by inducing cell death via intrinsic apoptotic pathways. Our previous studies in clinical settings have suggested that certain subpopulations of patients with acute myeloid leukemia (AML) had poor response to chemotherapy.MATERIALS AND METHODS: The effect of staurosporine on apoptosis and cell cycle distribution in human leukemic cell line U-937 cells was determined. U-937 cells were treated with staurosporine at 0.5 microM for 18 hours or 1 microM for 24 hours. Analyses of cell cycle distribution and apoptosis were performed using flow cytometric analysis. The effects of staurosporine on the targeted proteins were assessed by immunoblot analysis.RESULTS: A blockade of the cell cycle at the G(2)/M phase was observed in U-937 cells treated with staurosporine. A concomitant induction of apoptosis and activation of caspase-3 in U-937 cells was also achieved. Treatment of U-937 cells with staurosporine at 1 microM for 24 hours, compared with 0.5 microM for 18 hours, appeared to kill the leukemic more efficiently cells and this dose and duration may specifically target p27, Erk and Akt pathways that are important for cancer cell survival and resistance to treatment. We also show that the effects of stauroporine on cell cycle progression and apoptosis in U-937 cells are closely linked.CONCLUSION: Our results suggest that induction of apoptosis and inhibitory proliferation and survival pathways are important events induced by staurosporine. Understanding the conditions under which staurosporine shows high specificity and low toxicity in treatment of leukemic cells is of great importance for improving the efficacy of targeted therapeutics and overcoming resistance to chemotherapeutic agents.
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9. |
- Aronsson, Andreas, et al.
(författare)
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Översiktlig kustinventering 2002-2004 - Inventering och bedömning av stränder i Västernorrland
- 2005
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Huvudsyftet med denna översiktliga kustinventering har varit att peka ut områden som är viktiga för att bevara den biologiska mångfalden längs länets kust. Inventeringen omfattar landområdet inom 300 m från strandlinjen och ner till ca 1 meters djup ut i vattnet. Förutom en klassificering av den fysiska påverkansgraden längs stränderna för hela länets kuststräcka har även 356 objekt med indikationer på höga naturvärden inventerats i fält. Dessa områden har plockats ut med hjälp av kartor och flygbilder utifrån vissa utvalda biotoper som t. ex. sandstränder, grunda vikar, avsnörda vikar, vattendragsmynningar och vattensamlingar.Fältinventeringen har främst omfattat kärlväxter, makroalger, bottenfauna, strandskalbaggar samt mindre- och större vattensalamander. Inventeringen har genomförts under åren 2002 - 2004. Ångermanlandskusten inventerades 2002- 2003 och medelpadskusten 2004.
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10. |
- Boen, Rune, et al.
(författare)
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Beyond the global brain differences : intraindividual variability differences in 1q21.1 distal and 15q11.2 bp1-bp2 deletion carriers
- 2024
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Ingår i: Biological Psychiatry. - 0006-3223 .- 1873-2402. ; 95:2, s. 147-160
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Tidskriftsartikel (refereegranskat)abstract
- Background: Carriers of the 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants exhibit regional and global brain differences compared with noncarriers. However, interpreting regional differences is challenging if a global difference drives the regional brain differences. Intraindividual variability measures can be used to test for regional differences beyond global differences in brain structure.Methods: Magnetic resonance imaging data were used to obtain regional brain values for 1q21.1 distal deletion (n = 30) and duplication (n = 27) and 15q11.2 BP1-BP2 deletion (n = 170) and duplication (n = 243) carriers and matched noncarriers (n = 2350). Regional intra-deviation scores, i.e., the standardized difference between an individual's regional difference and global difference, were used to test for regional differences that diverge from the global difference.Results: For the 1q21.1 distal deletion carriers, cortical surface area for regions in the medial visual cortex, posterior cingulate, and temporal pole differed less and regions in the prefrontal and superior temporal cortex differed more than the global difference in cortical surface area. For the 15q11.2 BP1-BP2 deletion carriers, cortical thickness in regions in the medial visual cortex, auditory cortex, and temporal pole differed less and the prefrontal and somatosensory cortex differed more than the global difference in cortical thickness.Conclusions: We find evidence for regional effects beyond differences in global brain measures in 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants. The results provide new insight into brain profiling of the 1q21.1 distal and 15q11.2 BP1-BP2 copy number variants, with the potential to increase understanding of the mechanisms involved in altered neurodevelopment.
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11. |
- Bryhn, Andreas, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2019 : Resursöversikt
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fisken i havet är en resurs som rör sig fritt över nationella gränser. EU har därför en gemensam fiskeripolitik (GFP). Många arter som är viktiga för Sverige regleras inte i GFP och förvaltas därför nationellt.Denna rapport syftar till att:beskriva utvecklingen av fiskeripolitikenförklara den nuvarande politikens mål och regelverk och dess relation till mål och regler på miljöområdetförklara politikens nationella genomförande och det nationella handlingsutrymmetexemplifiera hur Havs- och vattenmyndigheten arbetat med att reglera fisket.
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12. |
- Bryhn, Andreas, et al.
(författare)
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Fisk- och skaldjursbestånd i hav och sötvatten 2020 : Resursöversikt
- 2021
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- I rapporten kan du ta del av bedömningen som görs av situationen för bestånd som regleras inom ramen för EU:s gemensamma fiskeripolitik (GFP). Bedömningarna baseras på det forskningssamarbete och den rådgivning som sker inom det Internationella Havsforskningsrådet (ICES). Totalt redovisas underlag och råd för 48 fisk- och skaldjursarter.De bestånd som förvaltas nationellt baseras på de biologiska underlagen, och rådgivningen i huvudsak på den forskning och övervakning samt analys som bedrivs av Institutionen för akvatiska resurser vid Sveriges lantbruksuniversitet (SLU Aqua) samt yrkesfiskets rapportering.
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13. |
- Carlström, Mattias, et al.
(författare)
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Nitric oxide deficiency and increased adenosine response of afferent arterioles in hydronephrotic mice with hypertension
- 2008
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Ingår i: Hypertension. - : American Heart Association. - 0194-911X .- 1524-4563. ; 51:5, s. 1386-1392
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Forskningsöversikt (refereegranskat)abstract
- Afferent arterioles were used to investigate the role of adenosine, angiotensin II, NO, and reactive oxygen species in the pathogenesis of increased tubuloglomerular feedback response in hydronephrosis. Hydronephrosis was induced in wild-type mice, superoxide dismutase-1 overexpressed mice (superoxide-dismutase-1 transgenic), and deficient mice (superoxide dismutase-1 knockout). Isotonic contractions in isolated perfused arterioles and mRNA expression of NO synthase isoforms, adenosine, and angiotensin II receptors were measured. In wild-type mice, N(G)-nitro-L-arginine methyl ester (L-NAME) did not change the basal arteriolar diameter of hydronephrotic kidneys (-6%) but reduced it in control (-12%) and contralateral arterioles (-43%). Angiotensin II mediated a weaker maximum contraction of hydronephrotic arterioles (-18%) than in control (-42%) and contralateral arterioles (-49%). The maximum adenosine-induced constriction was stronger in hydronephrotic (-19%) compared with control (-8%) and contralateral kidneys (+/-0%). The response to angiotensin II became stronger in the presence of adenosine in hydronephrotic kidneys and attenuated in contralateral arterioles. L-NAME increased angiotensin II responses of all of the groups but less in hydronephrotic kidneys. The mRNA expression of endothelial NO synthase and inducible NO synthase was upregulated in the hydronephrotic arterioles. No differences were found for adenosine or angiotensin II receptors. In superoxide dismutase-1 transgenic mice, strong but similar L-NAME response (-40%) was observed for all of the groups. This response was totally abolished in arterioles of hydronephrotic superoxide dismutase-1 knockout mice. In conclusion, hydronephrosis is associated with changes in the arteriolar reactivity of both hydronephrotic and contralateral kidneys. Increased oxidative stress, reduced NO availability, and stronger reactivity to adenosine of the hydronephrotic kidney may contribute to the enhanced tubuloglomerular feedback responsiveness in hydronephrosis and be involved in the development of hypertension.
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14. |
- Carlström, Mattias, et al.
(författare)
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Superoxide Dismutase 1 Limits Renal Microvascular Remodeling and Attenuates Arteriole and Blood Pressure Responses to Angiotensin II via Modulation of Nitric Oxide Bioavailability
- 2010
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Ingår i: Hypertension. - 0194-911X .- 1524-4563. ; 56:5, s. 907-913
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Tidskriftsartikel (refereegranskat)abstract
- Oxidative stress is associated with vascular remodeling and increased preglomerular resistance that are both implicated in the pathogenesis of renal and cardiovascular disease. Angiotensin II induces superoxide production, which is metabolized by superoxide dismutase (SOD) or scavenged by NO. We investigated the hypothesis that SOD1 regulates renal microvascular remodeling, blood pressure, and arteriolar responsiveness and sensitivity to angiotensin II using SOD1-transgenic (SOD1-tg) and SOD1-knockout (SOD1-ko) mice. Blood pressure, measured telemetrically, rose more abruptly during prolonged angiotensin II infusion in SOD1-ko mice. The afferent arteriole media: lumen ratios were reduced in SOD1-tg and increased in SOD1-ko mice. Afferent arterioles from nontreated wild types had graded contraction to angiotensin II (sensitivity: 10(-9) mol/L; responsiveness: 40%). Angiotensin II contractions were less sensitive (10(-8) mol/L) and responsive (14%) in SOD1-tg but more sensitive (10(-13) mol/L) and responsive (89%) in SOD1-ko mice. Arterioles from SOD1-ko had 4-fold increased superoxide formation with angiotensin II at 10(-9) mol/L. N-G-nitro-L-arginine methyl ester reduced arteriole diameter of SOD1-tg and enhanced angiotensin II sensitivity and responsiveness of wild-type and SOD1-tg mice to the level of SOD1-ko mice. SOD mimetic treatment with Tempol increased arteriole diameter and normalized the enhanced sensitivity and responsiveness to angiotensin II of SOD1-ko mice but did not affect wild-type or SOD1-tg mice. Neither SOD1 deficiency nor overexpression was associated with changes in nitrate/nitrite excretion or renal mRNA expression of NO synthase, NADPH oxidase, or SOD2/SOD3 isoforms and angiotensin II receptors. In conclusion, SOD1 limits afferent arteriole remodeling and reduces sensitivity and responsiveness to angiotensin II by reducing superoxide and maintaining NO bioavailability. This may prevent an early and exaggerated blood pressure response to angiotensin II.
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15. |
- Edsfeldt, Andreas, et al.
(författare)
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Soluble Urokinase Plasminogen Activator Receptor is Associated With Inflammation in the Vulnerable Human Atherosclerotic Plaque.
- 2012
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Ingår i: Stroke: a journal of cerebral circulation. - 1524-4628. ; 43:12, s. 3305-3312
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Tidskriftsartikel (refereegranskat)abstract
- Recently, plasma soluble urokinase plasminogen activator receptor (suPAR) has gained interest as a marker of cardiovascular risk. suPAR is released through the cleavage of urokinase plasminogen activator receptor (uPAR), which is found in monocytes, activated T-lymphocytes and endothelial cells, all involved in atherosclerosis. suPAR levels have been well studied in plasma, but no studies have focused on suPAR in human atherosclerotic plaques. The aim of this study was to determine whether suPAR measured in the plaque is associated with symptomatic plaques and plaque inflammation.
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16. |
- Felixsson, Emma, et al.
(författare)
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Horse chestnut extract contracts bovine vessels and affects human platelet aggregation through 5-HT(2A) receptors: an in vitro study
- 2010
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Ingår i: Phytotherapy Research. - : Wiley. - 0951-418X .- 1099-1573. ; 24:9, s. 1297-1301
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Tidskriftsartikel (refereegranskat)abstract
- Extract from seeds and bark of horse chestnut (Aesculus hippocastanum L) is used as an herbal medicine against chronic venous insufficiency. The effect and mechanism of action on veins, arteries, and platelets are not fully understood. The aim of this study was to investigate the effects and mechanisms of action of horse chestnut on the contraction of bovine mesenteric veins and arteries, and human platelet aggregation. Contraction studies showed that horse chestnut extract dose-dependently contracted both veins and arteries, with the veins being the most sensitive. Contraction of both veins and arteries were significantly inhibited by the 5-HT(2A) receptor antagonist ketanserin. No effect on contraction was seen with the cyclooxygenase inhibitor indomethacin, the alpha(1) receptor antagonist prazosin or the angiotensin AT(1) receptor antagonist saralasin neither in veins nor arteries. ADP-induced human platelet aggregation was significantly reduced by horse chestnut. A further reduction was seen with the extract in the presence of ketanserin. In conclusion, horse chestnut contraction of both veins and arteries is, at least partly, mediated through 5-HT(2A) receptors. Human platelet aggregation is reduced by horse chestnut. The clinical importance of these findings concerning clinical use, possible adverse effects, and drug interactions remains to be investigated. Copyright (c) 2010 John Wiley & Sons, Ltd.
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18. |
- Kaufmann, Tobias, et al.
(författare)
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Common brain disorders are associated with heritable patterns of apparent aging of the brain
- 2019
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Ingår i: Nature Neuroscience. - : Nature Publishing Group. - 1097-6256 .- 1546-1726. ; 22:10, s. 1617-
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Tidskriftsartikel (refereegranskat)abstract
- Common risk factors for psychiatric and other brain disorders are likely to converge on biological pathways influencing the development and maintenance of brain structure and function across life. Using structural MRI data from 45,615 individuals aged 3-96 years, we demonstrate distinct patterns of apparent brain aging in several brain disorders and reveal genetic pleiotropy between apparent brain aging in healthy individuals and common brain disorders.
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19. |
- Lai, En Yin, et al.
(författare)
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Norepinephrine increases calcium sensitivity of mouse afferent arteriole, thereby enhancing angiotensin II-mediated vasoconstriction
- 2009
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Ingår i: Kidney International. - : Elsevier BV. - 0085-2538 .- 1523-1755. ; 76:9, s. 953-959
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Tidskriftsartikel (refereegranskat)abstract
- Many agents constrict isolated afferent arterioles only at concentrations higher than their physiological levels. Here we determined if norepinephrine, as released by sympathetic nerve activity, could influence the angiotensin II responsiveness of isolated mouse afferent arterioles. Pretreatment of the arterioles for short periods with norepinephrine significantly increased the ability of 10 picomolar angiotensin II to constrict the vessels, an effect inhibited by the alpha receptor blockers prazosin (alpha-1) or yohimbine (alpha-2). Although the intracellular calcium transients induced by angiotensin were not different, phosphorylation of the 20 kDa myosin light chain was significantly increased in the presence of norepinephrine. Phosphorylation of the p38 mitogen-activated protein kinase was not changed. Phosphorylation of the myosin phosphatase targeting subunit at Thr696, but not at Thr850, was significantly enhanced by, norepinephrine pretreatment, thus increasing the calcium sensitivity of the arteriolar smooth muscle. Our results show that norepinephrine increases afferent arteriolar sensitivity to angiotensin II by means of alpha receptor activation, causing increased calcium sensitivity through phosphorylation of the myosin phosphatase targeting subunit. Kidney International (2009) 76, 953-959; doi:10.1038/ki.2009.261; published online 22 July 2009
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20. |
- Patzak, Andreas, et al.
(författare)
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Adenosine enhances long term the contractile response to angiotensin II in afferent arterioles
- 2007
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Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 293:6, s. R2232-R2242
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Tidskriftsartikel (refereegranskat)abstract
- Adenosine (Ado) enhances ANG II-induced constrictions of afferent arterioles (Af) by receptor-dependent and -independent pathways. Here, we test the hypothesis that transient Ado treatment has a sustained effect on Af contractility, resulting in increased ANG II responses after longer absence of Ado. Treatment with Ado (cumulative from 10(-11) to 10(-4) mol/l) and consecutive washout for 10 or 30 min increased constrictions on ANG II in isolated, perfused Af. Cytosolic calcium transients on ANG II were not enhanced in Ado-treated vessels. Selective or global inhibition of A(1)- and A(2)-adenosine receptors did not inhibit the Ado effect. Nitrobenzylthioinosine (an Ado transport inhibitor) clearly reduced the Ado-mediated responses. Selective inhibition of p38 MAPK with SB-203580 also prevented the Ado effect. Inosine treatment did not influence arteriolar reactivity to ANG II. Contractile responses of Af on norepinephrine and endothelin-1 were not influenced by Ado. Phosphorylation of the p38 MAPK and of the regulatory unit of 20-kDa myosin light chain was enhanced after Ado treatment and ANG II in Af. However, phosphorylation of p38 MAPK induced by norepinephrine or endothelin-1 was reduced in vessels treated with Ado, whereas 20-kDa myosin light chain was unchanged. The results suggest an intracellular, long-lasting mechanism including p38 MAPK activation responsible for the increase of ANG II-induced contractions by Ado. The effect is not calcium dependent and specific for ANG II. The prolonged enhancement of the ANG II sensitivity of Af may be important for tubuloglomerular feedback.
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23. |
- Patzak, Andreas, et al.
(författare)
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Angiotensin II response in afferent arterioles of mice lacking either the endothelial or neuronal isoform of nitric oxide synthase
- 2008
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Ingår i: American Journal of Physiology. Regulatory Integrative and Comparative Physiology. - : American Physiological Society. - 0363-6119 .- 1522-1490. ; 294:2, s. R429-R437
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study is to evaluate the impact of nitric oxide (NO) produced by endothelial NO synthase (eNOS) and neuronal NOS (nNOS) on the angiotensin II response in afferent arterioles (Af). Dose responses were assessed for angiotensin II in microperfused Af of mice homozygous for disruption of the eNOS gene [ eNOS(-/-)], or nNOS gene [ nNOS(-/-)], and their wild-type controls, eNOS(+/+) and nNOS(+/+). Angiotensin II at 10(-8) and 10(-6) mol/l reduced the lumen to 69% and 68% in eNOS(+/+), and to 59% and 50% in nNOS(+/+). N-G-nitro-L-arginine methyl ester (L-NAME) did not change basal arteriolar diameters, but augmented angiotensin II contraction, reducing diameters to 23% and 13% in eNOS(+/+), and 7% and 10% in nNOS(+/+) at 10(-8) and 10(-6) mol/l. The response to angiotensin II was enhanced in nNOS(-/-) mice (41% and 25% at 10(-8) and 10(-6) mol/l) and even more enhanced in eNOS(+/+) mice (12% and 9%) compared with nNOS(+/+) and eNOS(+/+). L-NAME led to complete constriction of Af in these groups. Mediato-lumen ratios of Af did not differ between controls and gene-deficient mice. mRNA expression of angiotensin II receptor types 1A and 1B and type 2 also did not differ. The results reveal that angiotensin II-induced release of NO from both eNOS and nNOS significantly contributes to the control of Af. Results also suggest that eNOS-derived NO is of greater importance than nNOS-derived NO in this isolated arteriolar preparation.
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