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- Ahlström, Christer, et al.
(författare)
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A method for accurate localization of the first heart sound and possible applications
- 2008
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Ingår i: Physiological Measurement. - : Institutionen för medicinsk teknik. - 0967-3334 .- 1361-6579. ; 29:3, s. 417-428
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Tidskriftsartikel (refereegranskat)abstract
- We have previously developed a method for localization of the first heart sound (S1) using wavelet denoising and ECG-gated peak-picking. In this study, an additional enhancement step based on cross-correlation and ECG-gated ensemble averaging (EA) is presented. The main objective of the improved method was to localize S1 with very high temporal accuracy in (pseudo-) real time. The performance of S1 detection and localization, with and without EA enhancement, was evaluated on simulated as well as experimental data. The simulation study showed that EA enhancement reduced the localization error considerably and that S1 could be accurately localized at much lower signal-to-noise ratios. The experimental data were taken from ten healthy subjects at rest and during invoked hyper- and hypotension. For this material, the number of correct S1 detections increased from 91% to 98% when using EA enhancement. Improved performance was also demonstrated when EA enhancement was used for continuous tracking of blood pressure changes and for respiration monitoring via the electromechanical activation time. These are two typical applications where accurate localization of S1 is essential for the results.
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- Ahlström, Christer, 1977-, et al.
(författare)
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Noninvasive investigation of blood pressure changes using the pulse wave transit time : A novel approach in the monitoring of hemodialysis patients
- 2005
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Ingår i: Journal of Artificial Organs. - : Springer Science and Business Media LLC. - 1434-7229 .- 1619-0904. ; 8:3, s. 192-197
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Tidskriftsartikel (refereegranskat)abstract
- Severe blood pressure changes are well known in hemodialysis. Detection and prediction of these are important for the well-being of the patient and for optimizing treatment. New noninvasive methods for this purpose are required. The pulse wave transit time technique is an indirect estimation of blood pressure, and our intention is to investigate whether this technique is applicable for hemodialysis treatment. A measurement setup utilizing lower body negative pressure and isometric contraction was used to simulate dialysis-related blood pressure changes in normal test subjects. Systolic blood pressure levels were compared to different pulse wave transit times, including and excluding the cardiac preejection period. Based on the results of these investigations, a pulse wave transit time technique adapted for dialysis treatment was developed and tried out on patients. To determine systolic blood pressure in the normal group, the total pulse wave transit time was found most suitable (including the cardiac preejection period). Correlation coefficients were r = 0.80 ± 0.06 (mean ± SD) overall and r = 0.81 ± 0.16 and r = 0.09 ± 0.62 for the hypotension and hypertension phases, respectively. When applying the adapted technique in dialysis patients, large blood pressure variations could easily be detected when present. Pulse wave transit time is correlated to systolic blood pressure within the acceptable range for a trend-indicating system. The method's applicability for dialysis treatment requires further studies. The results indicate that large sudden pressure drops, like those seen in sudden hypovolemia, can be detected. © The Japanese Society for Artificial Organs 2005.
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- Alehagen, Urban, et al.
(författare)
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Gender difference in adiponectin associated with cardiovascular mortality
- 2015
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Ingår i: BMC Medical Genetics. - : BioMed Central / Springer Verlag (Germany). - 1471-2350. ; 16:9
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Tidskriftsartikel (refereegranskat)abstract
- Background: It is important to identify cardiovascular diseases in patients at high risk. To include genetics into routine cardiological patients has therefore been discussed recently. We wanted to evaluate the association between high-molecular weight adiponectin and cardiovascular risk, and secondly in the same population evaluate if specific genotype differences regarding risk could be observed, and thirdly if gender differences could be seen. Method: Four hundred seventy-six elderly participants recruited from a rural community were included. All participants underwent a clinical examination, echocardiography, and blood sampling and the single nucleotide polymorphism (SNP) (rs266729) of adiponectin was analysed. Follow-up time was 6.7 years. Results: Those with high serum concentration of adiponectin had a more 2 fold increased cardiovascular risk, and it might be that females exhibits even higher risk where a more than 5 fold increased risk could be seen. The result could be demonstrated even in a multivariate model adjusting for well-known clinical risk factors. However, as the sample size was small the gender differences should be interpreted with caution. In the genotype evaluation the C/C carriers of the female group had a more than 9-fold increased risk of cardiovascular mortality, however the confidence interval was wide. Such genotype difference could not be found in the male group. Conclusion: High level of adiponectin was associated with increased cardiovascular risk. Also a gender difference in the genotype evaluation could be seen where the C/C carriers obtained higher risk in the female group but not in the male group. Thus, in order to identify patients at risk early, genetic analyses may add to the armamentarium used in the clinical routine. However, information should be regarded as hypothesis generating as the sample size was small and should stimulate further research in individualized cardiovascular prevention and treatment.
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7. |
- Alehagen, Urban, et al.
(författare)
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PDGF-D gene polymorphism is associated with increased cardiovascular mortality in elderly men
- 2016
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Ingår i: BMC Medical Genetics. - : BIOMED CENTRAL LTD. - 1471-2350. ; 17:62
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Tidskriftsartikel (refereegranskat)abstract
- Background: Platelet-derived growth factor (PDGF) D has been reported to be active in fibroblasts, and in areas of myocardial infarction. In this longitudinal study we evaluated the association between PDGF-D polymorphism and cardiovascular mortality, and attempted to discover whether specific genotype differences regarding risk could be observed, and if gender differences could be seen. Methods: Four hundred seventy-six elderly community participants were included in this study. All participants underwent a clinical examination, echocardiography, and blood sampling including PDGF-D single nucleotide polymorphism (SNP) analyses of the rs974819 A/A, G/A and G/G SNP. The follow-up time was 6.7 years. Results: No specific genotype of rs974819 demonstrated increased cardiovascular mortality in the total population, however, the male group with genotypes A/A and G/A demonstrated an increased risk that persisted in a multivariate evaluation where adjustments were made for well-known cardiovascular risk factors (2.7 fold compared with the G/G genotype). No corresponding finding was observed in the female group. Conclusion: We report here for the first time that the genotypes G/A or A/A of the SNP rs974819 near PDGF-D exhibited a 2.7 fold increased cardiovascular mortality risk in males. Corresponding increased risk could not be observed in either the total population and thus not in the female group. However, the sample size is was small and the results should be regarded as hypothesis-generating, and thus more research in the field is recommended.
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9. |
- Bergstrand, Sara, et al.
(författare)
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Existence of Tissue Blood Flow in Response to External Pressure in the Sacral Region of Elderly Individuals - Using an Optical Probe Prototype
- 2010
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Ingår i: MICROCIRCULATION. - : Taylor and Francis. - 1073-9688 .- 1549-8719. ; 17:4, s. 311-319
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Tidskriftsartikel (refereegranskat)abstract
- Pandgt;Objective: The aim was to investigate the existence of sacral tissue blood flow at different depths in response to external pressure and compression in elderly individuals using a newly developed optical probe prototype. Methods: The tissue blood flow and tissue thickness in the sacral area were measured during load in 17 individuals using laser Doppler flowmetry and photoplethysmography in a combined probe, and digital ultrasound. Results: The mean age was 68.6 +/- 7.0 years. While loading, the mean compression was 60.3 +/- 11.9%. The number of participants with existing blood flow while loading increased with increased measurement depth. None had enclosed blood flow deep in the tissue and at the same time an existing more superficial blood flow. Correlation between tissue thickness and BMI in unloaded and loaded sacral tissue was shown: r = 0.68 (P = 0.003) and r = 0.68 (P = 0.003). Conclusions: Sacral tissue is highly compressed by external load. There seems to be a difference in responses to load in the different tissue layers, as occluded blood flow in deeper tissue layers do not occur unless the blood flow in the superficial tissue layers is occluded.
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- Bjarnegård, Niclas, et al.
(författare)
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Age affects proximal brachial artery stiffness : differential behaviour within the length of the brachial artery?
- 2003
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Ingår i: Ultrasound in Medicine and Biology. - 0301-5629. ; 29:8, s. 1115-1121
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Tidskriftsartikel (refereegranskat)abstract
- With increasing age, the diameter of central elastic arteries increases, whereas their distensibility decreases. The purpose of this study was to investigate the mechanical properties of the proximal brachial artery in relation to age and gender. Distensibility coefficient (DC), stiffness and compliance coefficient (CC) were calculated in 136 healthy males and females (range 9-82 y) using echo-tracking sonography. CC decreased with age in both genders, but CC was higher in males. Stiffness increased and DC decreased with age in an exponential manner, without any differences between genders. In conclusion, as in central elastic arteries, the distensibility of the proximal brachial artery decreases with age, in contrast to earlier reports on the muscular distal brachial artery. This may imply that the transition between elastic and muscular artery behavior is within the length of the brachial artery. In future studies using the brachial artery, the examination site needs to be defined.
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- Bjarnegård, Niclas, et al.
(författare)
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Arterial properties along the upper arm in humans: age-related effects and the consequence of anatomical location
- 2010
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Ingår i: JOURNAL OF APPLIED PHYSIOLOGY. - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 108:1, s. 34-38
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Tidskriftsartikel (refereegranskat)abstract
- The normal aging process of the brachial artery (BA) wall is of specific interest since it is often selected as a model artery in studies of vascular function. With echo-tracking ultrasound, diameter, absolute diameter change, and intima-media thickness (IMT) were registered in 60 healthy subjects, 21-86 yr (30 men), at a proximal, upper third, and distal arterial site along the upper arm. Blood pressure was recorded noninvasively, and the distensibility coefficient (DC) was calculated. The diameter at the proximal site increased with age from 5.5 +/- 0.2 mm in the young subjects to 6.9 +/- 0.3 mm (P andlt; 0.01) in the elderly subjects, concomitantly as IMT increased from 0.40 +/- 0.01 to 0.65 +/- 0.03 mm (P andlt; 0.001). The diameter at the other sites was similar in the young and elderly subjects, whereas IMT increased slightly with age. At the proximal site, DC decreased dramatically from 40.7 +/- 2.2 to 10.1 +/- 0.8 10(-3)/kPa (P andlt; 0.001) with age, whereas hardly no change was seen in the distal upper arm. The principal transit zone between elastic to predominantly muscular artery behavior seems to be located within the proximal part of the brachial artery, emphasizing the importance of carefully defining the arterial examination site.
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13. |
- Bjarnegård, Niclas, 1964-
(författare)
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Aspects on wall properties of the brachial artery in man : with special reference to SLE and insulin-dependent diabetes mellitus
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The mechanical properties of the arterial wall are of great importance for blood pressure regulation and cardiac load. With increasing age, large arteries are affected by increased wall stiffness. Furthermore, atherosclerotic manifestations may increase the stiffness even further, both processes acting as independent cardiovascular risk factors affecting the arterial system in a heterogeneous way.The aims of this thesis was to characterize the local mechanical properties of brachial artery (BA) with the aid of ultrasound technique and to evaluate the influence of 1) age, gender, sympathetic stimulation and examination site; 2) type 1 diabetes (DM) and its association to circulatory biomarkers; and 3) to evaluate the general properties of the arterial system with the aid of pulse wave velocity (PWV) as well as pulse wave analysis (PWA) in systemic lupus erythematosus (SLE) and correlate the findings to disease activity and circulatory biomarkers.In the most proximal arterial segment of the upper arm a pronounced age-related decrease in wall distensibility, increase in intima-media thickness (IMT), and a slight increase in diameter were seen. Sympathetic stimulation had no influence on wall mechanics. More distally in BA, no change in diameter, and only minor increase in IMT and decrease in distensibility were seen. No gender differences were found. These findings suggest that the principle transit zone between elastic and muscular artery behaviour is located in the proximal part of the upper arm.Women with uncomplicated insulin-dependent DM had similar diameter, IMT and distensibility in their distal BA as controls, whereas flow-mediated dilatation (FMD) was slightly, and nitrate mediated dilatation (NMD) markedly reduced. NMD was negatively correlated with higher HbA1c levels. Vascular smooth muscle cell function seems to be an early manifestation of vascular disease in women with DM, influenced by long-term hyperglycaemia.Women with SLE had increased aortic PWV compared to controls, a finding positively associated with increased levels of complement factor 3 (C3), but not with disease activity. The increased stiffness of central arteries may be one factor contributing to the increased cardiovascular risk seen in SLE.
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14. |
- Bjarnegård, Niclas, et al.
(författare)
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Cardiovascular function in adulthood following intrauterine growth restriction with abnormal fetal blood flow
- 2013
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Ingår i: Ultrasound in Obstetrics and Gynecology. - : Wiley-Blackwell. - 0960-7692 .- 1469-0705. ; 41:2, s. 177-184
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To examine whether intrauterine growth restriction (IUGR) is associated with increased cardiovascular risk later in life. Methods We examined 19 young adults (aged 2225 years) who were born at term after IUGR, along with 18 controls. All had been examined previously with fetal Doppler, and in the present follow-up with echocardiography, carotid echo-tracking ultrasound, applanation tonometry, blood pressure and laser Doppler, in order to characterize their cardiac and vascular geometry and/or function. Results The diameter of the ascending aorta and the left ventricular diameter were smaller in the IUGR group, but only ascending aortic diameter remained significantly smaller after adjustment for body surface area (Pandlt;0.05). The aortic pressure augmentation index was higher in the IUGR group (Pandlt;0.05). The common carotid artery diameter, intimamedia thickness and distensibility as well as left ventricular mass and function were similar in the two groups. IUGR status was found to be an independent predictor of ascending aortic diameter. Conclusions IUGR due to placental dysfunction seems to contribute to the higher systolic blood pressure augmentation and the smaller aortic dimensions that are observed in adults more than 20 years later, with possible negative consequences for future left ventricular performance due to increased aortic impedance.
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17. |
- Bjarnegård, Niclas, et al.
(författare)
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Increased aortic pulse wave velocity in middle-aged women with systemic lupus erythematosus
- 2006
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Ingår i: Lupus. - : SAGE Publications. - 0961-2033 .- 1477-0962. ; 15:10, s. 644-650
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Tidskriftsartikel (refereegranskat)abstract
- Systemic lupus erythematosus (SLE) is a connective tissue disease where inflammatory activity affects several organ systems. An increased risk of cardiovascular disease has been identified in these patients, even after correction for traditional risk factors. The aim of the present study was to evaluate arterial stiffness and central hemodynamics in women with SLE in comparison to controls. Arterial tonometry was used to measure aortic (carotid-femoral) and arm (carotid-radial) pulse wave velocity (PWV), reflected pressure waves, and aortic augmentation index (AIx) in 27 women with SLE (52 to 68 years) and 27 controls. Aortic PWV was higher in women with SLE than controls, 9.8 m/s versus 8.2 m/s (P 0.01), after correction for mean arterial pressure and body mass index, 9.5 m/s versus 8.5 m/s (P 0.05). Other parameters were similar, arm PWV, 8.4 versus 8.5 m/s, AIx 34 versus 33% and calculated central aortic pulse pressure 48 versus 43 mmHg, in SLE and controls, respectively (NS). Aortic PWV was positively associated to C-reactive protein (CRP) and complement factor 3 (C3). Women with SLE have increased stiffness of their elastic central arteries. This may be one factor contributing to the increased cardiovascular risk seen in this cohort.
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19. |
- Bjarnegård, Niclas, et al.
(författare)
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Long-term hyperglycaemia impairs vascular smooth muscle cell function in women with type 1 diabetes mellitus
- 2009
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Ingår i: DIABETES and VASCULAR DISEASE RESEARCH. - : SAGE Publications. - 1479-1641 .- 1752-8984. ; 6:1, s. 25-31
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Tidskriftsartikel (refereegranskat)abstract
- Observations of increased stiffness in the elastic aorta in women with diabetes, but not men, emphasise the need for further analysis regarding early abnormalities in arterial wall properties of women with type 1 diabetes mellitus (DM).Ultrasound was used to study the wall properties of the distal brachial artery (BA) in 37 type 1 diabetic women (aged 22-45 years) without evident complications and in 53 controls (C). Blood samples were drawn for later analysis.Flow-mediated dilatation (FMD) was slightly lower in DM than C, 8.1 +/- 4.3% vs. 10.3 +/- 4.9% (p<0.05), and nitrate-mediated dilatation (NMD) was markedly lower, 21.7 +/- 6.6% vs. 31.4 +/- 5.7% (p<0.001). Lumen diameter, intima-media thickness and distensibility were similar in DM and C. Insulin-like growth factor (IGF-1) was lower in DM than C, 231 +/- 65 vs. 349 +/- 68 ng/ml (p<0.001). Glycosylated haemoglobin (HbA(1C)) and matrix metalloproteinase (MMP-9) were independent predictors of the reduced NMD in the DM.Brachial artery responsiveness to an exogenous donor of nitric oxide (NO) was markedly reduced in type 1 diabetic women despite only limited reduction in endothelium-dependent dilatation. The negative association between NMD and HbA(1C) suggests that long-term hyperglycaemia impairs vascular smooth muscle cell function in DM.
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20. |
- Bjarnegård, Niclas, et al.
(författare)
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The effect of sympathetic stimulation on proximal brachial artery mechanics in humans : differential behaviour within the length of the brachial artery
- 2004
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Ingår i: Acta Physiologica Scandinavica. - 0001-6772 .- 1365-201X. ; 182:1, s. 21-27
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Tidskriftsartikel (refereegranskat)abstract
- Aims: The mechanical properties of arteries play a major role in the regulation of blood pressure and cardiac performance. The effect of sympathetic stimulation on the mechanical properties of the proximal brachial artery was analysed in 18 healthy volunteers, nine young (25 ± 2 years) and nine elderly (69 ± 2 years).Methods: A non-invasive ultrasonic echo-tracking system for measurement of systolic/diastolic variation of the proximal brachial artery diameter in combination with intra-arterial pressure measurements was used to determine wall mechanics. The pressure–diameter (P–D) relationship, distensibility coefficient (DC), compliance coefficient (CC) and stiffness(β) were obtained at rest and during sympathetic stimulation induced by lower body negative pressure (LBNP).Results: The peripheral vascular resistance increased by 100 and 72%, respectively in the young and elderly during LBNP (P < 0.001). Simultaneously, the mechanical properties of the proximal brachial artery remained unaltered, as estimated from both P–D relationship and stiffness in young (β-index rest: 5.2 ± 0.9, LBNP: 5.5 ± 1.3, NS) as well as elderly (β-index rest: 13.6 ± 4.6, LBNP: 16.1 ± 4.7, NS).Conclusions: LBNP-induced sympathetic activation does not change proximal brachial artery mechanics, in contrast to earlier reports on the muscular distal brachial artery. This may imply that the transition between elastic and muscular artery behaviour is within the length of the brachial artery, where the site of transition from elastic to muscular wall structure needs to be specified in future studies.
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21. |
- Bjarnegård, Niclas, et al.
(författare)
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Vascular Adaptation to Indoor Cycling Exercise in Premenopausal Women
- 2019
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Ingår i: International Journal of Sports Medicine. - : GEORG THIEME VERLAG KG. - 0172-4622 .- 1439-3964. ; 40:4, s. 245-252
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Tidskriftsartikel (refereegranskat)abstract
- The early vascular adaptation to indoor cycling, a popular activity at many fitness centres, is incompletely evaluated. Forty two healthy women (21-45 years) underwent measurements of arterial wall properties and geometry as well as a maximal bicycle exercise test before and after a 3 months period during which 21 of the women joined indoor cycling classes at a gym 2-3 times per week, while 21 women served as time controls. Peak work load increased by in average 16% (pamp;lt;0.001) and ascending aortic diameter by 4% (pamp;lt;0.01) in the exercise group, while unchanged in control group. The exercise intervention had no significant influence on the local intima-media thickness, blood pressure or the pulse pressure wave configuration while the carotid artery distensibility (pamp;lt;0.05) was higher after the intervention. There was a positive correlation between change in () peak work load and -diameter of tubular ascending aorta (r=0.42, pamp;lt;0.01) in the exercise group. In conclusion, after only 3 months of bicycle exercise training, signs of central arterial remodelling were seen in premenopausal women, which was associated to improvement in exercise capacity.
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22. |
- Bjarnegård, Niclas, 1964-, et al.
(författare)
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Vascular characteristics in young women-Effect of extensive endurance training or a sedentary lifestyle
- 2018
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Ingår i: Acta Physiologica. - : Wiley. - 1748-1716 .- 1748-1708. ; 223:2
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To explore whether high-level endurance training in early age has an influence on the arterial wall properties in young women. Methods: Forty-seven athletes (ATH) and 52 controls (CTR), all 17-25 years of age, were further divided into runners (RUN), whole-body endurance athletes (WBA), sedentary controls (SC) and normally active controls (AC). Two-dimensional ultrasound scanning of the carotid arteries was conducted to determine local common carotid artery (CCA) geometry and wall distensibility. Pulse waves were recorded with a tonometer to determine regional pulse wave velocity (PWV) and pulse pressure waveform. Results: Carotid-radial PWV was lower in WBA than in RUN (P < .05), indicating higher arterial distensibility along the arm. Mean arterial pressure was lower in ATH than in CTR and in RUN than in WBA (P < .05). Synthesized aortic augmentation index (AI at 75) was lower among ATH than among CTR (-12.8 ± 1.6 vs -2.6 ± 1.2%, P < .001) and in WBA than in RUN (-16.4 ± 2.5 vs -10.7 ± 2.0%, P < .05), suggesting a diminished return of reflection waves to the aorta during systole. Carotid-femoral PWV and intima-media thickness (IMT), lumen diameter and radial distensibility of the CCA were similar in ATH and CTR. Conclusion: Elastic artery distensibility and carotid artery IMT are not different in young women with extensive endurance training over several years and in those with sedentary lifestyle. On the other hand, our data suggest that long-term endurance training is associated with potentially favourable peripheral artery adaptation, especially in sports where upper body work is added. This adaptation, if persisting later in life, could contribute to lower cardiovascular risk.
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24. |
- Björck, Hanna, et al.
(författare)
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Association of genetic variation on chromosome 9p21.3 and arterial stiffness
- 2009
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Ingår i: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 265:3, s. 373-381
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Tidskriftsartikel (refereegranskat)abstract
- Genome wide association studies have consistently reported associations between a region on chromosome 9p21.3 and a broad range of vascular diseases, such as coronary artery disease (CAD), aortic and intracranial aneurysms and type-2 diabetes (T2D). However, clear associations with intermediate phenotypes have not been described so far. To shed light on a possible influence of this chromosomal region on arterial wall integrity, we analysed associations between single nucleotide polymorphisms (SNPs) and degree of stiffness of the abdominal aorta in elderly individuals.A total of 400 subjects, 212 men and 188 women, aged 70-88 years were included. Arterial stiffness was examined at the midpoint between the renal arteries and the aortic bifurcation. Two CAD- and aneurysm-associated SNPs (rs10757274 and rs2891168) and one T2D-associated SNP (rs1081161) within the 9p21.3 region were genotyped. Aortic compliance and distensibility coefficients were higher in carriers of the rs10757274G and rs2891168G alleles in men reflecting a decrease in aortic stiffness. Adjustment for age and mean arterial pressure had no effect on these associations. The two SNPs were not associated with intima-media thickness or lumen diameter of the abdominal aorta. There were no associations between the rs10811661 SNP and any measure of aortic stiffness.Impaired mechanical properties of the arterial wall may explain the association between chromosome 9p21.3 polymorphisms and vascular disease.
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25. |
- Björck, Hanna, et al.
(författare)
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Gender-specific association of the plasminogen activator inhibitor-1 4G/5G polymorphism with central arterial blood pressure
- 2011
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Ingår i: American Journal of Hypertension. - New York, USA : Nature Publishing Group. - 0895-7061 .- 1941-7225. ; 24:7, s. 802-8
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Tidskriftsartikel (refereegranskat)abstract
- Background: The functional plasminogen activator inhibitor-1 (PAI-1) 4G/5G polymorphism has previously been associated with hypertension. In recent years, central blood pressure, rather than brachial has been argued a better measure of cardiovascular damage and clinical outcome. The aim of this study was to investigate the possible influence of the 4G/5G polymorphism on central arterial blood pressure in a cohort of elderly individuals.Methods: We studied 410 individuals, 216 men and 194 women, aged 70-88. Central pressures and pulse waveforms were calculated from the radial artery pressure waveform by the use of the SphygmoCor system and a generalized transfer function. Brachial pressure was recorded using oscillometric technique (Dinamap, Critikon, Tampa, FL). PAI-1 antigen was determined in plasma.Results: The results showed that central pressures were higher in women carrying the PAI-1 4G/4G genotype compared to female carriers of the 5G/5G genotype, (P = 0.025, P = 0.002, and P = 0.002 for central systolic-, diastolic-, and mean arterial pressure, respectively). The association remained after adjustment for potentially confounding factors related to hypertension. No association of the PAI-1 genotype with blood pressure was found in men. Multiple regression analysis revealed an association between PAI-1 genotype and plasma PAI-1 levels (P = 0.048).Conclusions: Our findings show a gender-specific association of the PAI-1 4G/5G polymorphism with central arterial blood pressure. The genotype effect was independent of other risk factors related to hypertension, suggesting that impaired fibrinolytic potential may play an important role in the development of central hypertension in women.
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26. |
- Björck, Hanna M., et al.
(författare)
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Characterization of Shear-Sensitive Genes in the NormalRat Aorta Identifies Hand2 as a Major Flow-ResponsiveTranscription Factor
- 2012
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:12
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Shear forces play a key role in the maintenance of vessel wall integrity. Current understanding regarding shear-dependent gene expression is mainly based on in vitro or in vivo observations with experimentally deranged shear, hence reflecting acute molecular events in relation to flow. Our objective was to determine wall shear stress (WSS) in the rat aorta and study flow-dependent vessel wall biology under physiological conditions.Methods and Results: Animal-specific aortic WSS magnitude and vector direction were estimated using computational fluid dynamic simulation based on aortic geometry and flow information acquired by MRI. Two distinct flow pattern regions were identified in the normal rat aorta; the distal part of the inner curvature being exposed to low WSS and a non-uniform vector direction, and a region along the outer curvature being subjected to markedly higher levels of WSS and a uniform vector direction. Microarray analysis revealed a strong differential expression between the flow regions, particularly associated with transcriptional regulation. In particular, several genes related to Ca2+-signalling, inflammation, proliferation and oxidative stress were among the most highly differentially expressed.Conclusions: Microarray analysis validated the CFD-defined WSS regions in the rat aorta, and several novel flow-dependent genes were identified. The importance of these genes in relation to atherosusceptibility needs further investigation.
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27. |
- Björck, Hanna, 1979-
(författare)
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Vessel wall integrity : influence of genetics and flow
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Cardiovascular disease (CVD) is the major cause of death worldwide. Underlying causes, such as atherosclerosis and hypertension, are associated with remodeling of the vessel wall ultimately leading to loss of structural integrity. There are a number of factors that can influence vascular remodeling and hence structural integrity. The overall aim of this thesis was to investigate aortic wall integrity in relation to genetics and blood flow.The influence of SNPs within the currently most robust susceptibility locus identified for CVD (chromosome 9p21.3) on abdominal aortic integrity was studied in elderly individuals. In men, risk-variants were associated with a decreased abdominal aortic stiffness, independent of other factors related to arterial stiffness. Impaired mechanical properties of the abdominal aortic wall may explain the association between chromosome 9p21.3 and vascular disease.Plasminogen activator inhibitor 1 (PAI-1) is the key inhibitor of fibrinolysis, and involved in several processes associated with vascular remodeling. We investigated the impact of the PAI-1 4G/5G polymorphism on central aortic blood pressure as this pressure more strongly relates to cardiovascular morbidity and mortality than the peripheral pressure. Elderly women carrying the 4G/4G genotype had higher central aortic blood pressure than women carrying the 5G/5G genotype. The association was regardless of other risk factors related to hypertension, suggesting that an impaired fibrinolytic potential may play an important role in the development of hypertension in women.Blood flow is a strong determinant of arterial growth and vascular function. We investigated flow-dependent gene expression and vessel wall morphology in the rat aorta under physiological conditions. Microarray analysis revealed a strong differential gene expression between disturbed and uniform flow pattern regions, particularly associated with transcriptional regulation. Moreover, several genes related to Ca2+ signalling were among the most highly differentially expressed. Up-regulation of Ca2+-related genes may be due to endothelial response to disturbed flow and assembly of cilia, consequently leading to functional and structural modifications of the vessel wall.Bicuspid aortic valve (BAV) is a congenital disorder associated with disturbed ascending aortic blood flow. Using a new strategy to dissect flow-mediated gene expression we identified several novel flow-associated genes, particularly related to angiogenesis, wound healing and mechanosensing, showing differential expression in the ascending aorta between BAV and tricuspid aortic valve patients. Fifty-five percent of the identified genes were confirmed to be flowresponsive in the rat aorta. A disturbed flow, and consequently an altered gene expression, may contribute to the increased aneurysm susceptibility associated with BAV morphology.
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28. |
- Blomstrand, Peter, et al.
(författare)
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Left ventricular diastolic function, assessed by echocardiography and tissue Doppler imaging, is a strong predictor of cardiovascular events, superior to global left ventricular longitudinal strain, in patients with type 2 diabetes
- 2015
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Ingår i: European Heart Journal Cardiovascular Imaging. - : Oxford University Press (OUP). - 2047-2404 .- 2047-2412. ; 16:9, s. 1000-1007
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Tidskriftsartikel (refereegranskat)abstract
- Aims: The aim of the study was to determine whether left ventricular systolic function, in terms of global left ventricular longitudinal strain (GLS), and diastolic function, expressed as the ratio between early diastolic transmitral flow and mitral annular motion velocities (E/e'), can predict cardiovascular events in patients with diabetes mellitus type 2.Methods and results: We prospectively investigated 406 consecutive patients, aged 55-65 years, with diabetes mellitus, who participated in the CARDIPP study. Echocardiography, pulse pressure (pp), and glycosylated haemoglobin (HbA1c) were analysed. Twelve cases of myocardial infarction and seven cases of stroke were identified during the follow-up period of 67 +/- 17 months. Univariate Cox regression analysis showed that E/e' was a strong predictor of cardiovascular events (hazards ratio 1.12; 95% confidence interval 1.06-1.18, P < 0.001). E/e' was prospectively associated with cardiovascular events independent of age, sex, GLS, left ventricular ejection fraction (LVEF), pp, and HbA1c in multivariate analysis. Receiver operating characteristic curves showed that E/e' and HbA1c were the strongest predictors for cardiovascular events, both having an area under the curve (AUC) of 0.71 followed by LVEF with an AUC of 0.65 and GLS of 0.61. In a Kaplan-Meyer analysis, the cumulative probability of an event during the follow-up period was 8.6% for patients with an E/e' ratio >15 compared with 2.6% for patients with E/e' <= 15, P = 0.011.Conclusion: In middle-aged patients with type 2 diabetes, E/e' is a strong predictor of myocardial infarction and stroke, comparable with HbA1c and superior to GLS and LVEF.
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29. |
- Blomstrand, Peter, et al.
(författare)
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Overweight and obesity impair left ventricular systolic function as measured by left ventricular ejection fraction and global longitudinal strain
- 2018
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Ingår i: Cardiovascular Diabetology. - : BioMed Central. - 1475-2840. ; 17:1
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Tidskriftsartikel (refereegranskat)abstract
- AimsObesity is associated with type 2 diabetes mellitus, left ventricular diastolic dysfunction and heart failure but it is unclear to which extent it is related to left ventricular systolic dysfunction. The aim of the study was to explore the effects of overweight and obesity on left ventricular systolic function in patients with type 2 diabetes mellitus and a control group of non-diabetic persons.MethodsWe prospectively investigated 384 patients with type 2 diabetes mellitus, and 184 controls who participated in the CARDIPP and CAREFUL studies. The participants were grouped according to body mass index (normal weight < 25 kg/m2, overweight 25–29 kg/m2, and obesity ≥ 30 kg/m2). Echocardiography was performed at the beginning of the study and after 4-years in the patient group.ResultsUnivariable and multivariable regression analysis revealed that variations in left ventricular ejection fraction, global longitudinal strain, left ventricular mass and diastolic function expressed as E/é (the ratio between early diastolic mitral flow and annular motion velocities) all are related to body mass index. The mean and standard deviation of left ventricular ejection fraction and global longitudinal strain values were 57% (8%) vs. − 18.6% (2.3%) for normal weight patients, 53% (8%) vs. − 17.5% (2.3%) for overweight, and 49% (9%) vs. − 16.2% (3.0%) for obese (p < 0.05 vs. p < 0.05). Corresponding results in the control group were 58% (6%) vs. − 22.3% (3.0%), 55% (7%) vs. − 20.8% (3.1%) and 54% (8%) − 19.6% (4.0%) (p < 0.05 vs. p < 0.05). Patients who gained weight from baseline to follow-up changed left ventricular ejection fraction (median and interquartile range) by − 1.0 (9.0) % (n = 187) and patients who lost weight changed left ventricular ejection fraction by 1.0 (10.0) % (n = 179) (p < 0.05).ConclusionOverweight and obesity impair left ventricular ejection fraction and global longitudinal strain in both patients with type 2 diabetes mellitus and non-diabetic persons.
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30. |
- Brodszki, Jana, et al.
(författare)
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Abnormal mechanical properties of larger arteries in postmenopausal women with systemic lupus erythematosus
- 2004
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Ingår i: Lupus. - : SAGE Publications. - 0961-2033 .- 1477-0962. ; 13:12, s. 917-923
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Tidskriftsartikel (refereegranskat)abstract
- There is limited knowledge of potential defects in arterial wall properties in female systemic lupus erythematosus (SLE) patients without manifest cardiovascular disease (CVD) and significant atherosclerotic lesions. The aim of the present study was to investigate the mechanical properties of larger vessels in these patients and to compare them with healthy controls. B-mode ultrasound was used to assess vessel wall structure and to exclude presence of plaque. The ankle/brachial pressure index was measured to exclude occlusive arterial disease. An ultrasound echo-tracking system was used to determine stiffness of the abdominal aorta, common carotid artery (CCA) and popliteal artery (PA) in 39 female patients with SLE and 55 female, healthy controls. SLE had an independent effect on stiffening of the CCA (P = 0.01) and PA (P = 0.005). In addition, larger vessel diameters were observed in the CCA (P = 0.002) after adjustments for the effects of mean arterial pressure and age. Thus, this investigation demonstrated an increased arterial stiffness and signs of premature vascular ageing in the SLE patients without manifest cardiovascular disease and without significant atherosclerotic lesions. The results of this study indicate that other mechanisms besides atherosclerosis might be involved in the pathogenesis of arterial stiffening in SLE patients.
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31. |
- Brodszki, Jana, et al.
(författare)
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Altered vascular function in healthy normotensive pregnant women with bilateral uterine artery notches.
- 2002
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Ingår i: BJOG: An International Journal of Obstetrics & Gynaecology. - : Wiley. - 1471-0528 .- 1470-0328. ; 109:5, s. 546-552
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To assess endothelial function and vascular mechanical properties in normotensive pregnant women with high resistance in the uteroplacental circulation. DESIGN: Cross-sectional prospective study. SETTING: Doppler ultrasound laboratory at university department of obstetrics and gynaecology referral centre for high risk pregnancies. PARTICIPANTS: Forty-two caucasian normotensive pregnant women: 23 with uncomplicated pregnancies and 19 with bilateral uterine artery notches. METHODS: Flow-mediated dilatation of the brachial artery was measured by ultrasonography at 25 gestational weeks. Concentrations of nitrite and nitrate in the plasma were established at 25 and 32 gestational weeks. The elastic properties of the common carotid artery, abdominal aorta and popliteal artery were measured with an ultrasonic echo-tracking system. RESULTS: Flow-mediated dilatation at two minutes after cuff deflation was significantly lower in the bilateral notch group compared with the control group, 8.3% and 13.7%, respectively (P = 0.0007). The ability to sustain vasodilatation was reduced in the bilateral notch group (P = 0.02). Lower values of nitrite and nitrate in the plasma were found at 32 gestational weeks in the bilateral notch group than in the control group (mean 24.76 microM/L (SD 5.6) and 30.93 microM/L (8.2), respectively; P = 0.008). Nitrite and nitrate levels tended to be lower in the bilateral notch group even at 25 gestational weeks (29.45 microM/L (8.3) and 35.73 microM/L (11.0) in the bilateral notch and control group, respectively; P = 0.09). There was no difference in aortic, carotid or popliteal elasticity between the two groups. CONCLUSIONS: Healthy normotensive pregnant women with bilateral uterine artery notches show impaired endothelial function, but no differences in vascular mechanical properties.
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32. |
- Brodszki, Jana, et al.
(författare)
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Impaired vascular growth in late adolescence after intrauterine growth restriction
- 2005
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Ingår i: Circulation. - 0009-7322 .- 1524-4539. ; 111:20, s. 2623-2628
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Tidskriftsartikel (refereegranskat)abstract
- Background - Abnormal blood flow in a fetus small for gestational age indicates true fetal intrauterine growth restriction (IUGR). We tested the hypothesis that IUGR with abnormal fetal blood flow is associated with long-term abnormal vascular morphology and function in adolescence. Methods and Results - In a prospective study, vascular mechanical properties of the common carotid artery (CCA), abdominal aorta , and popliteal artery (PA) were assessed by echo-tracking sonography in 21 adolescents with IUGR and abnormal fetal aortic blood flow and in 23 adolescents with normal fetal growth and normal fetal aortic blood flow. Endothelium-dependent and -independent vasodilatation of the brachial artery was measured by high-resolution ultrasound. After adjustment for body surface area and sex, the IUGR group had significantly smaller end-diastolic vessel diameters than the referents in the abdominal aorta and PA (mean difference, 1.7 mm [95% CI, 0.62 to 2.74] and 0.6 mm [95% CI, 0.25 to 1.02], respectively) (P=0.003 and P=0.002, respectively), with a similar trend in the CCA (P=0.09). A higher resting heart rate was observed in the IUGR group (P=0.01). No differences were found in stiffness or in endothelium-dependent and -independent vasodilatation between the 2 groups. Conclusions - IUGR caused by placental insufficiency appears to be associated with impaired vascular growth persisting into young adulthood in both men and women. The smaller aortic dimensions and the higher resting heart rate seen in adolescents with previous IUGR may be of importance for future cardiovascular health. © 2005 American Heart Association, Inc.
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33. |
- Brodszki, Jana, et al.
(författare)
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Vascular mechanical properties and endothelial function in pre-eclampsia with special reference to bilateral uterine artery notch
- 2008
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 87:2, s. 154-162
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Tidskriftsartikel (refereegranskat)abstract
- Objectives. To assess whether women with pre-eclampsia (PE) have different properties of the blood vessel wall compared to healthy pregnant controls. Further, to evaluate endothelial function and vascular mechanical properties in women with PE with special regard to its association with bilateral uterine artery notch and placental histopathology. Participants. Some 57 Caucasian pregnant women: 23 with uncomplicated pregnancies and normal uterine artery Doppler, and 34 with PE, the PE group comprising 2 subgroups according to the presence (n=20) or absence (n=14) of bilateral uterine artery notches. Methods. Ultrasonic echo-tracking assessed the elastic properties of the common carotid artery, abdominal aorta and popliteal artery. Flow-mediated dilatation (FMD) of the brachial artery was measured by ultrasonography. Histopathological examination of the placenta was carried out in 46 pregnancies: 18 uncomplicated pregnancies, 15 with PE with bilateral notch, and 13 with PE without bilateral notch. Results. There were no significant differences in carotid, aortic or popliteal vessel wall stiffness either between women with PE and controls or within the PE group. FMD was significantly lower in women with PE than in controls (p=0.03). The lowest FMD was observed in pre-eclamptic women with bilateral uterine artery notches 9.5% (SD: 5.3) compared to 11.6% (SD: 5.4) in pre-eclamptic women without bilateral uterine artery notch, and 13.4% (SD: 4.0) in controls (p=0.01). Bilateral uterine artery notching was significantly associated with a lower FMD (OR: 0.87, 95% CI: 0.77-0.98). There were significantly more placentas with high ischaemic score in the bilateral notch group than in the group with PE and normal circulation. Conclusions. There were no differences in vessel wall stiffness between women with PE and healthy controls. Women with PE showed signs of endothelial dysfunction, significantly more pronounced in women with bilateral uterine artery notch. Bilateral uterine artery notch was associated with ischaemic pathology of the placenta. Notwithstanding, a significant number of placentas in the PE group failed to show noteworthy ischaemic or other morphological changes that could explain the role of the placenta in the development of PE.
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34. |
- Cao, Ziquan, et al.
(författare)
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Hypoxia-induced retinopathy model in adult zebrafish
- 2010
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Ingår i: Nature Protocols. - : Nature Publishing Group. - 1754-2189 .- 1750-2799. ; 5:12, s. 1903-1910
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Tidskriftsartikel (refereegranskat)abstract
- Hypoxia-induced vascular responses, including angiogenesis, vascular remodeling and vascular leakage, significantly contribute to the onset, development and progression of retinopathy. However, until recently there were no appropriate animal disease models recapitulating adult retinopathy available. In this article, we describe protocols that create hypoxia-induced retinopathy in adult zebrafish. Adult fli1: EGFP zebrafish are placed in hypoxic water for 3-10 d and retinal neovascularization is analyzed using confocal microscopy. It usually takes 11 d to obtain conclusive results using the hypoxia-induced retinopathy model in adult zebrafish. This model provides a unique opportunity to study kinetically the development of retinopathy in adult animals using noninvasive protocols and to assess therapeutic efficacy of orally active antiangiogenic drugs.
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35. |
- Cao, Ziquan, 1982-
(författare)
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VEGF-mediated vascular functions in health and disease
- 2015
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Angiogenesis is essential for physiological processes including embryonic development, tissue regeneration, and reproduction. Under various pathological conditions the same angiogenic process contribute to the onset, development, and progression of many human diseases including cancer, diabetic complications, ocular disease, chronic inflammation and cardiovascular disease. Vascular endothelial growth factor (VEGF) is a key angiogenic factor for physiological and pathological angiogenesis. In addition to its strong angiogenic activity, VEGF also potently induces vascular permeability, often causing tissue edema in various pathological tissues. VEGF transduces its vascular signal through two tyrosine kinase receptors-VEGFR1 and VEGFR2, the latter being a functional receptor that mediates both angiogenic and vascular permeability effects. To study physiological and pathological functions of VEGF, we developed novel zebrafish disease models that permit us to study hypoxia-induced retinopathy and cancer metastasis processes. We have also administered anti-VEGF and anti-VEGFR specific antibodies to healthy mice to study the homeostatic role of VEGF in the maintenance of vascular integrity and its functions in various tissues and organs.Finally, using a zebrafish model, we evaluated if VEGF expression is regulated by circadian clock genes. In paper I, we developed protocols that create hypoxia-induced retinopathy in adult zebrafish. Adult fli1:EGFP zebrafish were placed in hypoxic water for 3-10 days with retinal neovascularization being analyzed using confocal microscopy. This model provides a unique opportunity to kinetically study the development of retinopathy in adult animals using non-invasive protocols and to assess the therapeutic efficacy of orally administered anti-angiogenic drugs. In paper II, we developed a zebrafish metastasis model to dissect the complex events of hypoxia-induced tumor cell invasion and metastasis in association with angiogenesis at the single-cell level. In this model, fluorescent DiI-labeled human or mouse tumor cells were implanted into the perivitelline cavity of 48-hour-old zebrafish embryos, which were subsequently placed in hypoxic water for 3 days. Tumor cell invasion, metastasis and pathological angiogenesis were analyzed using fluorescent microscopy in the living fish. The average experimental time for this model is 7 days. Our protocol offers an opportunity to study molecular mechanisms of hypoxia-induced cancer metastasis. In paper III, we show that systemic delivery of an anti-VEGF or an anti-VEGF receptor (VEGFR)-2 neutralizing antibody cause global vascular regression in mice. Among all examined tissues, the vasculature in endocrine glands, intestinal villi, and the uterus are most affected in response to VEGF or VEGFR-2 blockades. Pro-longed anti-VEGF treatment resulted in a significant decrease in the circulating levels of the predominant thyroid hormone, free thyroxine, but not the minimal isoform of triiodothyronine, suggesting that chronic anti-VEGF treatment impairs thyroid function. These findings provide structural and functional bases of anti-VEGF-specific druginduced side effects in relation to vascular changes in healthy tissues. In paper IV, we show that disruption of the circadian clock by constant exposure to light coupled with genetic manipulation of key genes in the zebrafish led to impaired developmental angiogenesis. A bmal1-specific morpholino inhibited developmental angiogenesis in zebrafish embryos without causing obvious nonvascular phenotypes. Conversely, a period2 morpholino accelerated angiogenic vessel growth, suggesting that Bmal1 and Period2 display opposing angiogenic effects. These results offer mechanistic insights into the role of the circadian clock in regulation of developmental angiogenesis, and our findings may be reasonably extended to other types of physiological or pathological angiogenesis. Overall, the results in this thesis provide further insight to angiogenic mechanistic properties in tissues and suggest possible novel therapeutic targets for the treatment of various angiogenesis-dependent diseases.
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36. |
- Carlsson, Axel C., et al.
(författare)
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Association of soluble tumor necrosis factor receptors 1 and 2 with nephropathy, cardiovascular events, and total mortality in type 2 diabetes
- 2016
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Ingår i: Cardiovascular Diabetology. - : Springer Science and Business Media LLC. - 1475-2840. ; 15
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Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS: Soluble tumor necrosis factor receptors 1 and 2 (sTNFR1 and sTNFR2) contribute to experimental diabetic kidney disease, a condition with substantially increased cardiovascular risk when present in patients. Therefore, we aimed to explore the levels of sTNFRs, and their association with prevalent kidney disease, incident cardiovascular disease, and risk of mortality independently of baseline kidney function and microalbuminuria in a cohort of patients with type 2 diabetes. In pre-defined secondary analyses we also investigated whether the sTNFRs predict adverse outcome in the absence of diabetic kidney disease.METHODS: The CARDIPP study, a cohort study of 607 diabetes patients [mean age 61 years, 44 % women, 45 cardiovascular events (fatal/non-fatal myocardial infarction or stroke) and 44 deaths during follow-up (mean 7.6 years)] was used.RESULTS: Higher sTNFR1 and sTNFR2 were associated with higher odds of prevalent kidney disease [odd ratio (OR) per standard deviation (SD) increase 1.60, 95 % confidence interval (CI) 1.32-1.93, p < 0.001 and OR 1.54, 95 % CI 1.21-1.97, p = 0.001, respectively]. In Cox regression models adjusting for age, sex, glomerular filtration rate and urinary albumin/creatinine ratio, higher sTNFR1 and sTNFR2 predicted incident cardiovascular events [hazard ratio (HR) per SD increase, 1.66, 95 % CI 1.29-2.174, p < 0.001 and HR 1.47, 95 % CI 1.13-1.91, p = 0.004, respectively]. Results were similar in separate models with adjustments for inflammatory markers, HbA1c, or established cardiovascular risk factors, or when participants with diabetic kidney disease at baseline were excluded (p < 0.01 for all). Both sTNFRs were associated with mortality.CONCLUSIONS/INTERPRETATIONS: Higher circulating sTNFR1 and sTNFR2 are associated with diabetic kidney disease, and predicts incident cardiovascular disease and mortality independently of microalbuminuria and kidney function, even in those without kidney disease. Our findings support the clinical utility of sTNFRs as prognostic markers in type 2 diabetes.
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37. |
- Carlsson, Axel C., et al.
(författare)
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The association between endostatin and kidney disease and mortality in patients with type 2 diabetes
- 2016
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Ingår i: Diabetes & Metabolism. - : Elsevier BV. - 1262-3636 .- 1878-1780. ; 42:5, s. 351-357
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Tidskriftsartikel (refereegranskat)abstract
- Aim. - Circulating endostatin, a biologically active derivate of collagen XVIII, is considered to be a marker of kidney disease and a risk factor for its related mortality. However, less is known of the role of endostatin in diabetes and the development of diabetic nephropathy. For this reason, our study investigated the associations between circulating endostatin and the prevalence and progression of kidney disease, and its mortality risk in patients with type 2 diabetes (T2D). Methods. - This was a cohort study of 607 patients with T2D (mean age: 61 years, 44% women). Estimated glomerular filtration rate (eGFR), calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) creatinine equation, was used to assess the patients' kidney function decline and mortality. Results. - Of the total study cohort, 20 patients declined by >= 20% in eGFR over 4 years, and 44 died during the follow-up (mean duration: 6.7 years). At baseline, participants with diabetic nephropathy (defined as eGFR < 60 mL/min/1.73 m(2)) and/or microalbuminuria [defined as a urinary albumin-to-creatinine ratio (ACR) > 3 g/mol] had higher median levels of endostatin than those without nephropathy (62.7 mu g/L vs 57.4 mu g/L, respectively; P = 0.031). In longitudinal analyses adjusted for age, gender, baseline eGFR and ACR, higher endostatin levels were associated with a higher risk of decline (>= 20% in eGFR, OR per 1 SD increase: 1.73, 95% CI: 1.13-2.65) and a higher risk of mortality (HR per 1 SD increase: 1.57, 95% CI: 1.19-2.07). Conclusion. - In patients with T2D, circulating endostatin levels can predict the progression of kidney disease and mortality independently of established kidney disease markers. The clinical usefulness of endostatin as a risk marker in such patients merits further studies.
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38. |
- Cinthio, Magnus, et al.
(författare)
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Longitudinal Movement of the Common Carotid Artery Wall : New Information on Cardiovascular Aging
- 2018
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Ingår i: Ultrasound in Medicine and Biology. - : Elsevier BV. - 0301-5629 .- 1879-291X. ; 44:11, s. 2283-2295
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Tidskriftsartikel (refereegranskat)abstract
- Putative changes in the multiphasic pattern of longitudinal movement of the common carotid artery wall in the normal aging process are unknown. The aim of this study was to explore the phases, and resulting patterns, of the longitudinal movement of the intima–media complex of the human common carotid artery with respect to age and gender. One hundred thirty-five healthy non-smoking patients of different ages were investigated using in-house-developed ultrasound methods. The patterns of longitudinal movement seen in middle-aged and older patients were markedly different from those commonly seen in young patients, including the appearance of two additional phases of motion and, thus, new complex patterns. The displacement and maximum velocity of one of the phases, occurring at the time of aortic valve closure, increased quadratically with age in both men and women.
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39. |
- Dahl Jensen, Lasse, et al.
(författare)
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Opposing Effects of Circadian Clock Genes Bmal1 and Period2 in Regulation of VEGF-Dependent Angiogenesis in Developing Zebrafish
- 2012
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Ingår i: Cell Reports. - : Elsevier (Cell Press). - 2211-1247. ; 2:2, s. 231-241
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Tidskriftsartikel (refereegranskat)abstract
- Molecular mechanisms underlying circadian-regulated physiological processes remain largely unknown. Here, we show that disruption of the circadian clock by both constant exposure to light and genetic manipulation of key genes in zebrafish led to impaired developmental angiogenesis. A bmal1-specific morpholino inhibited developmental angiogenesis in zebrafish embryos without causing obvious nonvascular phenotypes. Conversely, a period2 morpholino accelerated angiogenic vessel growth, suggesting that Bmal1 and Period2 display opposing angiogenic effects. Using a promoter-reporter system consisting of various deleted vegf-promoter mutants, we show that Bmal1 directly binds to and activates the vegf promoter via E-boxes. Additionally, we provide evidence that knockdown of Bmal1 leads to impaired Notch-inhibition-induced vascular sprouting. These results shed mechanistic insight on the role of the circadian clock in regulation of developmental angiogenesis, and our findings may be reasonably extended to other types of physiological or pathological angiogenesis.
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40. |
- Dahl Jensen, Lasse, et al.
(författare)
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Zebrafish Models to Study Hypoxia-Induced Pathological Angiogenesis in Malignant and Nonmalignant Diseases
- 2011
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Ingår i: Birth Defects Research. Part C: Embryo Today Reviews. - : John Wiley and Sons.Ltd. - 1542-975X .- 1542-9768. ; 93:2, s. 182-193
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Forskningsöversikt (refereegranskat)abstract
- Most in vivo preclinical disease models are based on mouse and other mammalian systems. However, these rodent-based model systems have considerable limitations to recapitulate clinical situations in human patients. Zebrafish have been widely used to study embryonic development, behavior, tissue regeneration, and genetic defects. Additionally, zebrafish also provides an opportunity to screen chemical compounds that target a specific cell population for drug development. Owing to the availability of various genetically manipulated strains of zebrafish, immune privilege during early embryonic development, transparency of the embryos, and easy and precise setup of hypoxia equipment, we have developed several disease models in both embryonic and adult zebrafish, focusing on studying the role of angiogenesis in pathological settings. These zebrafish disease models are complementary to the existing mouse models, allowing us to study clinically relevant processes in cancer and nonmalignant diseases, which otherwise would be difficult to study in mice. For example, dissemination and invasion of single human or mouse tumor cells from the primary site in association with tumor angiogenesis can be studied under normoxia or hypoxia in zebrafish embryos. Hypoxia-induced retinopathy in the adult zebrafish recapitulates the clinical situation of retinopathy development in diabetic patients or age-related macular degeneration. These zebrafish disease models offer exciting opportunities to understand the mechanisms of disease development, progression, and development of more effective drugs for therapeutic intervention.
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41. |
- Dahlén, Elsa M, et al.
(författare)
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Abdominal Obesity and low grade Systemic Inflammation as Markers for Subclinical Organ Damage in type 2 diabetes
- 2014
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Ingår i: Diabetes & Metabolism. - : Elsevier. - 1262-3636 .- 1878-1780. ; 40:1, s. 76-81
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Tidskriftsartikel (refereegranskat)abstract
- The aim of this study was to explore associations between abdominal obesity, inflammatory markers, and subclinical organ damage in 740 patients with type 2 diabetes. Waist circumference (WC) and sagittal abdominal diameter (SAD) was measured. Blood samples were analyzed for; C-reactive protein (CRP), interleukin (IL) -1β and IL-6. Carotid intimamedia thickness (IMT) was evaluated by ultrasonography. Aortic pulse wave velocity (PWV) was measured with applanation tonometry.Abdominal obesity were significantly correlated with; IL-6, CRP (both p= <0.001, WC and SAD, respectively), IMT (WC p=0.012, SAD p=0.003) and PWV (p<0.001, for WC and SAD, respectively). In multiple linear regressions with IMT as dependent variable and age, sex, statins, systolic blood pressure (SBP), Body Mass Index (BMI), CRP and HbA1c, as independent variables, SAD (p=0.047) but not WC, remained associated with IMT. In stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.We conclude that SAD and WC are feasible measures of obesity that provides information on inflammation, atherosclerosis and arterial stiffness in type 2 diabetes. However, SAD was slightly more robustly associated to subclinical organ damage, compared with WC.
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42. |
- Dahlén, Elsa M, et al.
(författare)
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Complications Carotid intima-media thickness and apolipoprotein B/apolipoprotein A-I ratio in middle-aged patients with Type 2 diabetes
- 2009
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Ingår i: Diabetic Medicine. - : Wiley. - 0742-3071 .- 1464-5491. ; 26:4, s. 384-390
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: To explore the association between carotid intima-media thickness (IMT) and the apolipoprotein B (apoB)/apolipoprotein A-I (apoA-I) ratio compared with conventional lipids in middle-aged patients with Type 2 diabetes. METHODS: We analysed data from 247 patients with Type 2 diabetes, aged 55-66 years, in the Cardiovascular Risk factors in Patients with Diabetes-a Prospective study in Primary care (CARDIPP-1) study. Primary care nurses measured blood pressure and anthropometric characteristics. Blood samples were taken for laboratory analyses. The carotid IMT was determined by ultrasonography at the University Hospital in Linköping and at the County Hospital Ryhov, Jönköping, Sweden. RESULTS: The ApoB/apoA-I ratio (r = 0.207, P = 0.001), apoB (r = 0.166, P = 0.009) and non-high-density lipoprotein cholesterol (non-HDL-c) (r = 0.129, P = 0.046) correlated with IMT. Conventional lipids, high-sensitivity C-reactive protein (hsCRP), glycated haemoglobin (HbA(1c)) and systolic blood pressure were not significantly correlated to IMT. A stepwise logistic regression analysis was conducted with IMT as the dependent variable and the apoB/apoA-I ratio, HbA(1c), hsCRP, low-density lipoprotein cholesterol (LDL-c), total cholesterol, non-HDL-c and treatment with statins as independent variables. Following adjustment for age and gender, only the apoB/apoA-I ratio remained significantly associated with IMT (odds ratio 4.3, 95% confidence intervals 1.7-10.8, P = 0.002). CONCLUSIONS: We conclude that there was a significant association between the apoB/apoA-I ratio and IMT in middle-aged patients with Type 2 diabetes. The association was independent of conventional lipids, hsCRP, glycaemic control and use of statins.
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43. |
- Dahlén, Elsa M, et al.
(författare)
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Is there an underestimation of intima-media thickness based on M-mode ultrasound technique in the abdominal aorta?
- 2012
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Ingår i: Clinical Physiology and Functional Imaging. - : Wiley-Blackwell. - 1475-0961 .- 1475-097X. ; 32:1, s. 1-4
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Tidskriftsartikel (refereegranskat)abstract
- Measuring intima-media thickness (IMT) in the common carotid artery (CCA) is a valuable resource for the evaluation of subclinical atherosclerosis. The main objective of this study was to explore whether a B-mode ultrasound technique, Philips ATL, and an M-mode ultrasound technique, Wall Track System (WTS), show interchangeable results when measured in CCA and the abdominal aorta (AA). A total of 24 healthy, young subjects were examined. IMT and lumen diameter (LD) of the AA and the CCA were measured twice by two skilled ultrasonographers with two different ultrasound equipment B-mode: (Philips, ATL and M-mode: WTS).The intra-observer variability of IMT in CCA and AA using B-mode showed a coefficient of variation 8% and 9%, and with M-mode 11% and 15%, respectively. Interobserver variability of IMT in CCA and AA using B-mode was 6% and 12%, and with M-mode 11% and 18%, respectively. CCA IMT was 0·53 ± 0·07 and 0·53 ± 0·09 mm using B-mode and M-mode, respectively. However, in AA, IMT was 0·61 ± 0·5 and 0·54 ± 0·10 mm using B-mode and M-mode, respectively. Thus, AA IMT was 11·5% thicker using B-mode (P<0·01). We received adequate IMT readings from the carotid artery as well as the AA using two commonly used B-mode and M-mode techniques. B-mode technique seems to show less variability, especially in the AA. More importantly, the two techniques measured different IMT thickness in the aorta, emphasizing the importance of using similar technique when comparing the impact of absolute values of IMT on cardiovascular disease.
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44. |
- Dahlén, Elsa M, et al.
(författare)
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Sagittal Abdominal Diameter is a more Independent Measure compared with Waist Circumference to predict Arterial Stiffness in subjects with Type 2 Diabetes
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Aim: The aim of this study was to prospectively explore how laboratory and anthropometric risk factors predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years. Methods: Baseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55-65 years old. Results: There were significant correlations between apolipoprotein B (apoB) (r= 0.144, p=0.03), C - reactive protein (CRP) (r=0.172, p=0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r=0.130, p=0.049), waist circumference (WC) (r=0.147, p=0.027) and sagittal Abdominal Diameter (SAD) (r=0.184, p=0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p=0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV. Conclusion: We conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.
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45. |
- Dahlén, Elsa M, et al.
(författare)
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Sagittal abdominal diameter is a more independent measure compared with waist circumference to predict arterial stiffness in subjects with type 2 diabetes - a prospective observational cohort study
- 2013
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Ingår i: Cardiovascular Diabetology. - : BioMed Central. - 1475-2840. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundAnthropometric measurements are useful in clinical practice since they are non-invasive and cheap. Previous studies suggest that sagittal abdominal diameter (SAD) may be a better measure of visceral fat depots. The aim of this study was to prospectively explore and compare how laboratory and anthropometric risk markers predicted subclinical organ damage in 255 patients, with type 2 diabetes, after four years.MethodsBaseline investigations were performed in 2006 and were repeated at follow-up in 2010. Carotid intima-media thickness (IMT) was evaluated by ultrasonography and aortic pulse wave velocity (PWV) was measured with applanation tonometry over the carotid and femoral arteries at baseline and at follow-up in a cohort of subjects with type 2 diabetes aged 55–65 years old.ResultsThere were significant correlations between apolipoprotein B (apoB) (r = 0.144, p = 0.03), C - reactive protein (CRP) (r = 0.172, p = 0.009) at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r = 0.130, p = 0.049), waist circumference (WC) (r = 0.147, p = 0.027) and sagittal Abdominal Diameter (SAD) (r = 0.184, p = 0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p = 0.036). In a stepwise linear regression, entering both SAD and WC, the association between SAD and PWV was stronger than the association between WC and PWV.ConclusionsWe conclude that apoB and CRP, but not LDL-cholesterol predicted subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.
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46. |
- Dahlén, Elsa, 1975-
(författare)
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Markers of subclinical atherosclerosis and arterial stiffness in type 2 diabetes
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Type 2 diabetes is a common disease with increased mortality and morbidity due to cardiovascular disease (CVD). This thesis is based on three studies that evaluated traditionally used and emerging risk markers to identify individuals with high-risk of developing CVD in middle-aged men and women with type 2 diabetes. One study was conducted to compare the equivalence between two different ultrasound techniques to measure intima-media thickness since IMT was used to evaluate subclinical atherosclerosis as a surrogate endpoint.Methods: Data from the cohort study, cardiovascular risk in type 2 diabetes – a prospective study in primary care (CARDIPP) was used in paper I, III and IV. In paper I, baseline data from the first 247 subjects was analysed. Associations between traditionally measured lipids, apolipoproteins, glycaemic control and low-grade inflammation and IMT were analysed.In paper III, the full baseline cohort, with data from 761 subjects from the CARDIPP study was cross-sectionally analysed regarding correlations between abdominal obesity measured as waist circumference (WC) and sagittal abdominal diameter (SAD), inflammatory markers and IMT and pulse wave velocity (PWV). In paper IV, the associations reported in paper I and III were prospectively investigated with data from the first year of follow-up four years after the baseline investigations in CARDIPP-revisited.In paper II a study was performed on 24 young healthy subjects, both men and women. IMT was measured in the common carotid artery (CCA) and in the abdominal aorta (AA), by two skilled ultrasonographers, with 2 different ultrasound techniques in a randomised order.Results: ApoB/apoA-I ratio (r=0.207, p=0.001), apoB (r=0.166, p=0.009) and non HDLcholesterol (nHDL-c) (0.129, p=0.046) correlated with IMT.In CCA IMT was equivalent using B-mode- and M-mode respectively. However in AA, IMT was 11.5% thicker using B-mode.Abdominal obesity were significantly correlated with; IL-6 and CRP (both p<0.001, WC and SAD respectively), IMT (WC p=0.012, SAD p=0.003) and PWV (p<0.001 WC and SAD respectively). Adjusting for age, sex, treatment with statins, systolic blood pressure (SBP), Body Mass Index (BMI), CRP and HbA1c, SAD (p=0.047) but not WC, remained associated with IMT.There were significant correlations between apoB (r=0.144, p=0.03) and CRP (r=0.172, p=0.009) measured at baseline and IMT measured at follow-up. After adjustment for sex, age, treatment with statins and Hba1c, the associations remained statistically significant. HbA1c, total cholesterol or LDL-cholesterol did not correlate to IMT at follow-up. Baseline body mass index (BMI) (r=0.130, p=0.049), WC (r=0.147, p=0.027) and SAD (r=0.184, p=0.007) correlated to PWV at follow-up. Challenged with sex, SBP and HbA1c, the association between SAD, not WC nor BMI, and PWV remained statistically significant (p=0.036).Conclusions: There was a significant association between apoB/apoA-I ratio and IMT. The association was independent of conventional lipids, CRP, glycaemic control and use of statins. Both SAD and WC were associated with inflammation, atherosclerosis and arterial stiffness. However, SAD was slightly more robustly associated to subclinical organ damage, compared with WC. Prospectively; apoB and CRP, but not LDL-cholesterol predicted increased subclinical atherosclerosis. Furthermore, SAD was more independent in predicting arterial stiffness over time, compared with WC, in middle-aged men and women with type 2 diabetes.The two different ultrasound techniques, B-mode and M-mode, measured different IMT thickness in the aorta, emphasizing the importance of using similar technique when comparing the impact of absolute values of IMT on cardiovascular disease.
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47. |
- De Basso, Rachel, et al.
(författare)
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Increased cardiovascular risk without generalized arterial dilating diathesis in persons who do not have abdominal aortic aneurysm but who are first-degree relatives of abdominal aortic aneurysm patients
- 2015
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Ingår i: Clinical and Experimental Pharmacology and Physiology. - : Wiley. - 1440-1681 .- 0305-1870. ; 42:6, s. 576-581
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Tidskriftsartikel (refereegranskat)abstract
- There is a strong genetic predisposition towards abdominal aortic aneurysm (AAA), but it is unknown whether persons without AAA but with first-degree relatives who are AAA patients have a generalized dilating diathesis, defect arterial wall mechanics, or increased cardiovascular risk. The aim of the study was to investigate arterial diameters and wall mechanics at multiple arterial sites in these subjects and compare them with controls without a family history of AAA. This study included 118 first-degree relatives of patients with AAA and 66 controls (age: 40-80years). The abdominal aorta, common carotid artery, common femoral artery, and popliteal artery were investigated by echo-tracking ultrasound. The relatives had no arterial dilatation, but they did tend to have smaller diameters than controls. Relatives had a higher heart rate, diastolic blood pressure, and mean arterial pressure than controls. The distensibility coefficient and the compliance coefficient were decreased in all arteries in male relatives, adjusted for age and smoking; these coefficients were normalized after adjustment for mean arterial pressure and heart rate. Female relatives had a lower compliance coefficient in the abdominal aorta, adjusted for age and smoking. After adjustment for mean arterial pressure and heart rate, the difference disappeared. No general arterial dilatation in relatives without AAA was found, supporting the hypothesis that the dilating diathesis is linked to the aneurysmal manifestation in the abdominal aorta. Although the threat of aneurysmal dilatation and rupture seems to be lacking in these subjects, heart rate, blood pressure, and arterial wall stiffness were all increased, which may indicate a higher risk of developing cardiovascular morbidity and mortality.
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48. |
- De Basso, Rachel, et al.
(författare)
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Increased carotid plaque burden in men with the fibrillin-1 2/3 genotype
- 2014
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Ingår i: Clinical and Experimental Pharmacology and Physiology. - : Wiley. - 1440-1681 .- 0305-1870. ; 41:9, s. 637-642
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Tidskriftsartikel (refereegranskat)abstract
- Fibrillin-1 (FBN1) is an important constituent of the vascular wall and earlier studies have indicated an effect of the FBN1 2/3 genotype on blood pressure as well as aortic stiffness in men. The aim of the present study was to determine whether the FBN1 2/3 genotype was associated with the presence of carotid plaque and incident cardiovascular morbidity and mortality in middle-aged subjects. The FBN1 genotype was characterized in 5765 subjects (2424 men, 3341 women; age 45-69years) recruited from the Malmo Diet and Cancer Study Cardiovascular Cohort, Sweden. Plaque occurrence and intima-media thickness (IMT) of the carotid artery were assessed by ultrasound. The incidence of first cardiovascular events (myocardial infarction and stroke) and cause-specific mortality were monitored over a mean follow-up period of 13.2years. The most common FBN1 genotypes were 2/2, 2/3 and 2/4, which accounted for 92.2% (n=5317) of subjects. There were no differences between the three genotypes regarding age, blood pressure, glucose, lipids, smoking habits, common carotid artery diameter and intima-media thickness in men and women. The presence of plaque in the carotid artery was higher in men with the 2/3 genotype compared with the 2/2 and 2/4 genotypes (55% vs 46% and 50%, respectively; P=0.007). No similar differences were observed in women. No significant relationship was observed between FBN1 genotypes and the incidence of cardiovascular disease or all-cause mortality. The increased prevalence of plaque in the carotid artery of middle-aged men with the FBN1 2/3 genotype indicates pathological arterial wall remodelling with a more pronounced atherosclerotic burden.
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49. |
- De Basso, Rachel
(författare)
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Influence of genetics and mechanical properties on large arteries in man
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Arterial pathology is the major contributor to cardiovascular diseases and mortality. The mechanical properties of arteries are independent factors for cardiovascular disease and mortality, where genetics influence the structure of the arterial wall, which may result in change in arterial stiffness. The aims of this thesis were to study the mechanical properties of the popliteal artery (PA) in healthy subjects and the influence of angiotensin-converting enzyme (ACE) polymorphism and Fibrillin-1 (FBN1) polymorphism on large arteries. Further, the impact of FBN1 polymorphism on cardiovascular morbidity and mortality was investigated.The PA is, after the abdominal aorta, the most common site of aneurysmal development. The PA was studied in healthy subject with ultrasound and the diameter increased and the distensibility decreased with age, with men having lower distensibility than women. This seems not to be the behavior of a true muscular artery but rather of a central elastic artery such as the aorta, and might have implications for the susceptibility to aneurysm formation, as well as the association of dilating disease between the PA and the aorta. The wall stress in the PA was low and unaffected by age, probably caused by a compensatory remodeling response with an increase in wall thickness. This indicates that other mechanisms than wall stress contribute to the process of pathological dilatation in the PA.The ACE D allele may be associated with abdominal aortic aneurysm. Elderly men with the ACE D allele were associated with increased abdominal aortic stiffness compared to men carrying the I/I genotype. This suggests that the ACE D allele impairs arterial wall integrity, and in combination with local hemodynamic and other genetic factors it may have a roll in aneurysm formation.The FBN1 2/3 genotype has been associated with increased systolic blood pressure. The FBN1 2/3 genotype in middle-aged men was associated with increased abdominal aortic stiffness and blood pressure which indicates an increased risk for developing cardiovascular disease. The increased presence of plaque in the carotid artery of middle-aged men with the FBN1 2/3 genotype indicates a pathological arterial wall remodeling with a more pronounced atherosclerotic burden, but did however not affect the risk of cardiovascular events and/or death in this population. This relationship needs to be studied further.
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50. |
- De Basso, Rachel, et al.
(författare)
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Low wall stress in popliteal artery – other mechanisms responsible for the predilection of aneurysmal dilatation?
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: The popliteal artery (PA) is, after aorta, the most common site for aneurysm formation. Why the PA is more susceptible than other peripheral muscular arteries is unknown. We hypothesised that the wall composition, which in turn affects wall properties, as well as the circumferential wall stress imposed on the arterial wall, might differ compared to other muscular arteries. The aim was to study the circumferential wall stress of the PA in healthy subjects with the adjacent muscular common femoral artery (CFA) as a comparison.Material and Methods: Ninety-four healthy subjects were included in this study (45 males, range 10-78 years and 49 females, range 10-83 years). The lumen diameter (LD) and intima-media thickness (IMT) in the PA and CFA were investigated with a Philips P700 ultrasound device. Together with blood pressure the circumferential wall stress was defined according to the law of Laplace adjusted for IMT.Results: The diameter increased with age in both PA and CFA (P<.001), with males having larger diameter than females (P<.001). IMT increased with age in both PA and CFA (P<.001), with higher IMT values in males only in PA (P<0.001). The calculated wall stress was unchanged with age in both arteries, but lower in PA than in CFA in both male and female subjects (P<0.001).Conclusion: This study shows that the popliteal and common femoral artery wall stress is maintained during ageing, probably due to compensatory remodeling response with an increase in arterial wall thickness. However, the stress imposed on the popliteal artery wall is quite low, indicating that other mechanisms than wall stress contribute to the process of pathological arterial dilatation in the popliteal artery.
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