| 1. |
- Ahlsson, Anders, 1962-
(författare)
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Atrial fibrillation in cardiac surgery
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Atrial fibrillation (AF) is the most common arrhythmia seen in clinical practice. In cardiac surgery, one-third of the patients experience episodes of AF during the first postoperative days (postoperative AF), and patients with preoperative AF (concomitant AF) can be offered ablation procedures in conjunction with surgery, in order to restore ordinary sinus rhythm (SR). The aim of this work was to study the relation between postoperative AF and inflammation; the long-term consequences of postoperative AF on mortality and late arrhythmia; and atrial function after concomitant surgical ablation for AF. In 524 open-heart surgery patients, C-reactive protein (CRP) serum concentrations were measured before and on the third day after surgery. There was no correlation between levels of CRP and the development of postoperative AF. All 1,419 patients with no history of AF, undergoing primary aortocoronary bypass surgery (CABG) in the years 1997–2000 were followed up after 8.0 years. The mortality rate was 191 deaths/1,000 patients (19.1%) in patients with no AF and 140 deaths/419 patients (33.4%) in patients with postoperative AF. Postoperative AF was an age-independent risk factor for late mortality, with a hazard ratio (HR) of 1.56 (95% CI 1.23–1.98). Postoperative AF patients had a more than doubled risk of death due to cerebral ischaemia, myocardial infarction, sudden death, and heart failure compared with patients without AF. All 571 consecutive patients undergoing primary CABG during the years 1999–2000 were followed-up after 6 years. Questionnaires were obtained from 91.6% of surviving patients and an electrocardiogram (ECG) from 88.3% of all patients. In postoperative AF patients, 14.1% had AF at follow-up, compared with 2.8% of patients with no AF at surgery (p<.001). An episode of postoperative AF was found to be an independent risk factor for development of late AF, with an adjusted risk ratio (RR) of 3.11 (95% CI 1.41–6.87). Epicardial microwave ablation was performed in 20 open-heart surgery patients with concomitant AF. Transthoracic echocardiography was performed preoperatively and at 6 months postoperatively. At 12 months postoperatively 14/19 patients (74%) were in SR with no anti-arrhythmic drugs. All patients in SR had preserved left and right atrial filling waves (A-waves) and Tissue velocity echocardiography (TVE) showed preserved atrial wall velocities and atrial strain. In conclusion, postoperative AF is an independent risk factor for late mortality and later development of AF. There is no correlation between the inflammatory marker CRP and postoperative AF. Epicardial microwave ablation of concomitant AF results in SR in the majority of patients and seems to preserve atrial mechanical function.
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| 2. |
- Ahlsson, Anders, et al.
(författare)
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Atrial function after epicardial microwave ablation in patients with atrial fibrillation
- 2008
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Ingår i: Scandinavian Cardiovascular Journal. - : Taylor & Francis. - 1401-7431 .- 1651-2006. ; 42:3, s. 192-201
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To study epicardial microwave ablation of concomitant atrial fibrillation and its effects on heart rhythm and atrial function during follow-up. DESIGN: The study included 20 open-heart surgery patients with concomitant atrial fibrillation. Transthoracic echocardiography with flow and tissue Doppler recordings was performed preoperatively and at 6 months postoperatively. Blood samples were obtained preoperatively and postoperatively for analysis of atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), and amino terminal precursor of brain natriuretic peptide (NT-proBNP). RESULTS: Fourteen of 19 patients (74%) were in sinus rhythm with no antiarrhythmic drugs at 12 months. All patients in sinus rhythm had preserved left and right atrial-filling waves through atrioventricular valves during atrial contraction. Tissue velocity echocardiography on patients in sinus rhythm showed preserved atrial wall velocities, atrial strain, and atrial strain rate. Levels of natriuretic peptides tended to decrease in patients with stable sinus rhythm at one year compared to patients in atrial fibrillation. CONCLUSIONS: Epicardial microwave ablation results in sinus rhythm in a majority of patients and seems to preserve atrial mechanical function
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| 3. |
- Ahlsson, Anders J., et al.
(författare)
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Postoperative atrial fibrillation is not correlated to C-reactive protein
- 2007
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Ingår i: Annals of Thoracic Surgery. - : Elsevier BV. - 0003-4975 .- 1552-6259. ; 83:4, s. 1332-1337
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The peak incidence of postoperative atrial fibrillation (AF) occurs around the second postoperative day, a time at which serum inflammatory markers are elevated. The aim of this study was to investigate differences between patients with and without postoperative AF with special regard to C-reactive protein (CRP) serum levels. METHODS: The study cohort included all heart surgery patients who had sinus rhythm preoperatively, survived postoperative day 3, and were operated on between July 1, 2004, and June 30, 2005 (n = 524). Any episode of AF during the first 7 postoperative days defined the patient as belonging to the postoperative AF group. Creatine kinase-myocardial band (CK-MB) was measured at postoperative day 1, and CRP was measured preoperatively and at postoperative day 3. Risk factors for postoperative AF were determined using bivariate and multivariate regression analysis. RESULTS: Of 524 patients, 182 had at least one episode of AF (34.7%). Preoperative and postoperative CRP concentrations did not differ between the groups (postoperative CRP 175.4 +/- 64.4 versus 175.3 +/- 60.1 mg/L respectively, p = 0.99). Atrial fibrillation patients were significantly older (p < 0.001) and had higher CK-MB levels (33.6 +/- 53.1 microg/L versus 22.5 +/- 26.7 microg/L, respectively, p = 0.009). The odds ratio for postoperative AF with postoperative CK-MB greater than 70 microg/L was 3.5 (confidence interval: 1.4 to 8.6). CONCLUSIONS: Postoperative AF has no correlation to the inflammatory marker CRP in heart surgery patients. Ischemic myocardial injury might predispose for postoperative AF.
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| 4. |
- Ahlsson, Anders, 1962-, et al.
(författare)
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Patients with postoperative atrial fibrillation have a doubled cardiovascular mortality
- 2009
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Ingår i: Scandinavian cardiovascular journal : SCJ. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 43:5, s. 330-336
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: To investigate the impact of postoperative AF on late mortality and cause of death in CABG patients.DESIGN: All CABG patients without preoperative AF surgically treated between January 1, 1997 and June 30, 2000 were included (N = 1419). Altogether, 419 patients (29.5%) developed postoperative AF. After a median follow-up of 8.0 years, survival data were obtained, causes of death were compared and Cox proportional hazard analysis was used to determine predictors of late mortality.RESULTS: The total mortality was 140 deaths/419 patients (33.4%) in postoperative AF patients and 191 deaths/1 000 patients (19.1%) in patients without AF. Death due to cerebral ischemia (2.6% vs. 0.5%), myocardial infarction (7.4% vs. 3.0%), sudden death (2.6% vs. 0.9%), and heart failure (6.7% vs. 2.7%) was more common among postoperative AF patients. Postoperative AF was an age-independent risk indicator for late mortality with a hazard ratio (HR) of 1.56 (95% confidence interval 1.23-1.98).CONCLUSIONS: Postoperative AF is an age-independent risk factor for late mortality in CABG patients, explained by an increased risk of cardiovascular death.
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| 5. |
- Liuba, Ioan, et al.
(författare)
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Source of inflammatory markers in patients with atrial fibrillation
- 2008
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Ingår i: Europace. - : Oxford University Press. - 1099-5129 .- 1532-2092. ; 10, s. 848-853
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Tidskriftsartikel (refereegranskat)abstract
- Aims Elevated levels of C-reactive protein and other inflammatory markers have been reported in some patients with atrial fibrillation (AF). Whether this finding is related to AF per se or to other conditions remains unclear. In addition, the source of inflammatory markers is unknown. Therefore, in the present study, we sought to assess the extent and the source of inflammation in patients with AF and no other concomitant heart or inflammatory conditions. Methods and results The study group consisted of 29 patients referred for radiofrequency catheter ablation: 10 patients with paroxysmal AF, 8 patients with permanent AF, and 10 control patients with Wolf-Parkinson-White (WPW) syndrome and no evidence of AF (mean age 54±11 vs. 57±13 vs. 43±16). No patient had structural heart diseases or inflammatory conditions. High-sensitive C-reactive protein, interleukin-6 (IL-6), and interleukin-8 (IL-8) were assessed in blood samples from the femoral vein, right atrium, coronary sinus, and the left and right upper pulmonary veins. All samples were collected before ablation. Compared with controls and patients with paroxysmal AF, patients with permanent AF had higher plasma levels of IL-8 in the samples from the femoral vein, right atrium, and coronary sinus, but not in the samples from the pulmonary veins (median values in the femoral vein: 2.58 vs. 2.97 vs. 4.66 pg/mL, P = 0.003; right atrium: 2.30 vs. 3.06 vs. 3.93 pg/mL, P = 0.013; coronary sinus: 2.85 vs. 3.15 vs. 4.07, P = 0.016). A high-degree correlation existed between the IL-8 levels in these samples (correlation coefficient between 0.929 and 0.976, P< 0.05). No differences in the C-reactive protein and IL-6 levels were noted between the three groups of patients. Conclusion The normal levels of C-reactive protein and IL-6, alongwith the elevated levels of IL-8 in patients with permanent AF but not in those with paroxysmal AF, suggest a link between a low-grade inflammatory reaction and long-lasting AF. The elevated IL-8 levels in the peripheral blood, right atrium, and coronary sinus but not in the pulmonary veins suggest a possible source of inflammation in the systemic circulation.
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| 6. |
- Agåker, Marcus, et al.
(författare)
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Novel instruments for ultra-soft X-ray emission spectroscopy
- 2009
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 601:1-2, s. 213-219
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Tidskriftsartikel (refereegranskat)abstract
- Two alternative instrument designs to the traditional Rowland grating spectrometer for high resolution ultra-soft X-ray spectroscopy are presented. The first instrument is a plane grating spectrometer using off-axis parabolic mirrors for collection and refocusing, and with a spatially resolving multichannel detector with delay line read-out. The instrument offers substantially higher performance in terms of resolution and sensitivity than traditional instruments. The second instrument is a Fourier transform spectrometer based on a grazing incidence Mach-Zehnder interferometer using wavefront dividing beamsplitters. The path length difference can be scanned over 0.1 mm, which corresponds to a resolution of 12 meV. (C) 2009 Elsevier B.V. All rights reserved.
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| 7. |
- Almroth, Henrik, et al.
(författare)
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Atorvastatin and persistent atrial fibrillation following cardioversion : a randomized placebo-controlled multicentre study
- 2009
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Ingår i: European Heart Journal. - Philadelphia : Oxford University Press (OUP). - 0195-668X .- 1522-9645. ; 30:7, s. 827-833
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: To evaluate the effect of atorvastatin in achieving stable sinus rhythm (SR) 30 days after electrical cardioversion (CV) in patients with persistent atrial fibrillation (AF). METHODS AND RESULTS: The study included 234 patients. The patients were randomized to treatment with atorvastatin 80 mg daily (n = 118) or placebo (n = 116) in a prospective, double-blinded fashion. Treatment was initiated 14 days before CV and was continued 30 days after CV. The two groups were well-balanced with respect to baseline characteristics. Mean age was 65 +/- 10 years, 76% of the patients were male and 4% had ischaemic heart disease. Study medication was well-tolerated in all patients but one. Before primary endpoint 12 patients were excluded. In the atorvastatin group 99 patients (89%) converted to SR at electrical CV compared with 95 (86%) in the placebo group (P = 0.42). An intention-to-treat analysis with the available data, by randomization group, showed that 57 (51%) in the atorvastatin group and 47 (42%) in the placebo group were in SR 30 days after CV (OR 1.44, 95%CI 0.85-2.44, P = 0.18). CONCLUSION: Atorvastatin was not statistically superior to placebo with regards to maintaining SR 30 days after CV in patients with persistent AF.
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| 8. |
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| 9. |
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| 10. |
- Englund, Gunilla, et al.
(författare)
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Efflux transporters in ulcerative colitis : decreased expression of BCRP (ABCG2) and Pgp (ABCB1)
- 2007
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Ingår i: Inflammatory Bowel Diseases. - : Oxford University Press (OUP). - 1078-0998 .- 1536-4844. ; 13:3, s. 291-297
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Tidskriftsartikel (refereegranskat)abstract
- Background: Efflux transport proteins are important components of the intestinal barrier against bacterial toxins, carcinogens, and drugs. This investigation was conducted to determine the expression of Breast Cancer Resistance Protein (BCRP/ABCG2), P-glycoprotein (Pgp/MDR1/ABCB1), and Multidrug Resistance Protein 2 (MRP2/ABCC2) in the gut mucosa of patients with ulcerative colitis (UC). Methods: Patients were thoroughly diagnosed according to well-established clinical, endoscopic, and histologic criteria to be included in the group of patients with active UC (n = 16) or UC in remission (n = 17). Colonic and rectal mucosa from patients with UC were compared with tissues from control subjects (n = 15). The mRNA expression (TaqMan) of the efflux transporters and the proinflammatory cytokines interleukin (IL)-1β and IL-6 was determined. Western blot was used in the analysis of protein expression and the tissue localization of BCRP was determined with confocal microscopy. Results: BCRP and Pgp expression was strongly reduced in individuals with active inflammation compared with controls and was negatively correlated with the levels of IL-6 mRNA. The BCRP staining of colonic epithelium seen in healthy mucosa was diminished in inflamed tissues, with concurrent disruption of epithelial F-actin structure. Conclusions: Two of the efflux transporters of importance for the barrier function of the gut mucosa, Pgp and BCRP, are expressed at strongly reduced levels during active inflammation in patients with UC. Investigations are warranted to determine whether the low levels of efflux transporters during active UC contribute to altered transport and tissue exposure of carcinogens, bacterial toxins, and drugs.
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| 11. |
- Englund, Gunilla, et al.
(författare)
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Regional levels of drug transporters along the human intestinal tract : Co-expression of ABC and SLC transporters and comparison with Caco-2 cells
- 2006
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Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier BV. - 0928-0987 .- 1879-0720. ; 29:3-4, s. 269-277
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Tidskriftsartikel (refereegranskat)abstract
- A vast number of drugs are subjected to active or facilitated transport and multiple transport mechanism may contribute to the net flux during drug absorption. The main objective of this study was to quantify the regional mRNA expression and determine the co-expression of drug transporters from the ABC (Pgp, BCRP, MRP2, MRP3) and SLC (PEPT1, MCT1, OATPB, OCTN2, OCT1) families along the human intestine (duodenum, jejunum, ileum, and colon). A second objective was to compare the transporter expression between the different intestinal regions and Caco-2 cells. Eight out of nine of the investigated transporters exhibited significant regional differences in expression. OATPB was the only transporter that did not show a region-dependency in the expression along the human intestinal canal. The expression of Pgp, BCRP, OCTN2 and MCT1 differed along the small intestine, but the expression differences were greater than five-fold only for Pgp. The rank order of transcript prevalence was identical in the ileum and the jejunum. Between the ileum and colon, seven transcripts were differentially expressed, and MCT1, OCTN2 and MRP3 were expressed at higher levels in the colon than in the small intestine. The expression of transporters in Caco-2 was closest to the expression pattern in the small intestine, although the expression of OATPB, BCRP and MRP2 differed more than five-fold between the Caco-2 cells and ileum. In conclusion, this study provides quantitative data on the expression of transporters from the ABC and SLC families along the human intestine, which can be useful in the interpretation of clinical studies where more than one intestinal transporter contribute to the net transport and in the computer modelling of drug absorption.
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| 12. |
- Furuland, Hans, et al.
(författare)
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Heart rate variability is decreased in chronic kidney disease but may improve with hemoglobin normalization
- 2008
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Ingår i: JN. Journal of Nephrology. - 1121-8428 .- 1724-6059. ; 21:1, s. 45-52
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Tidskriftsartikel (refereegranskat)abstract
- Background: Cardiac autonomic function can be measured by heart rate variability (HRV). Dialysis patients have an abnormally low HRV and are at increased risk for sudden death. A reduction in HRV is associated with anemia. HRV was therefore measured in patients with chronic kidney disease (CKD) after hemoglobin normalization. Methods: Sixteen nondiabetic patients with CKD stage 4 (glomerular filtration rate 23.7 13.9 ml/min) and renal anemia received epoetin aiming at a hemoglobin level of 135-150 g/L. HRV was measured by 24-hour Holter electrocardiogram at baseline and after hemoglobin normalization and in a reference group consisting of 16 volunteers without impairment of renal function. Results: Hemoglobin level increased from 100.7 12.6 g/L to 142.4 7.2 g/L during the study. At baseline, HRV measured in the time domain as the standard deviation of all normal RR intervals in the entire 24-hour electrocardiogram (SDNN) was 116.3 39.2 ms compared with 147.5 27.2 ms in the reference group (p<0.05). The frequency domain measures low-frequency power and total power were 367.7 350.2 ms2 and 1,368.9 957.4 ms2 compared with 717.3 484.5 ms2 and 2,228.3 1142.4 ms2 (p<0.05) in the reference group. After hemoglobin normalization there was an increase in low-frequency power to 498.3 432.7 ms2 (p<0.05) and in total power to 1,731.0 1,069.4 ms2 (p<0.05) while SDNN remained at 120.9 33.8 ms (p=ns). Conclusions: CKD patients not yet on dialysis had a reduced HRV, indicating impaired autonomic function, compared with a reference group without impaired renal function. Hemoglobin normalization improved but did not fully normalize HRV. The clinical significance of this deserves further investigation.
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| 13. |
- Haïssaguerre, Michel, et al.
(författare)
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Sudden cardiac arrest associated with early repolarization
- 2008
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Ingår i: New England Journal of Medicine. - 0028-4793 .- 1533-4406. ; 358:19, s. 2016-2023
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Early repolarization is a common electrocardiographic finding that is generally considered to be benign. Its potential to cause cardiac arrhythmias has been hypothesized from experimental studies, but it is not known whether there is a clinical association with sudden cardiac arrest.METHODS: We reviewed data from 206 case subjects at 22 centers who were resuscitated after cardiac arrest due to idiopathic ventricular fibrillation and assessed the prevalence of electrocardiographic early repolarization. The latter was defined as an elevation of the QRS-ST junction of at least 0.1 mV from baseline in the inferior or lateral lead, manifested as QRS slurring or notching. The control group comprised 412 subjects without heart disease who were matched for age, sex, race, and level of physical activity. Follow-up data that included the results of monitoring with an implantable defibrillator were obtained for all case subjects.RESULTS: Early repolarization was more frequent in case subjects with idiopathic ventricular fibrillation than in control subjects (31% vs. 5%, P<0.001). Among case subjects, those with early repolarization were more likely to be male and to have a history of syncope or sudden cardiac arrest during sleep than those without early repolarization. In eight subjects, the origin of ectopy that initiated ventricular arrhythmias was mapped to sites concordant with the localization of repolarization abnormalities. During a mean (+/-SD) follow-up of 61+/-50 months, defibrillator monitoring showed a higher incidence of recurrent ventricular fibrillation in case subjects with a repolarization abnormality than in those without such an abnormality (hazard ratio, 2.1; 95% confidence interval, 1.2 to 3.5; P=0.008).CONCLUSIONS: Among patients with a history of idiopathic ventricular fibrillation, there is an increased prevalence of early repolarization.
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| 14. |
- Kesek, Milos, et al.
(författare)
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Entrapment of circular mapping catheter in the mitral valve
- 2007
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Ingår i: Heart rhythm : the official journal of the Heart Rhythm Society. - New York, NY : Elsevier. - 1547-5271. ; 4:1, s. 17-19
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Ablation procedures in the left atrium for treatment of atrial fibrillation are becoming increasingly common. The procedure often involves placing one or two circular mapping catheters in the left atrium. Entrapment of an ablation catheter in the mitral valve during ablations of left-sided accessory pathways by the retrograde approach has been described in two earlier published reports. More recently, several reports describe similar entrapment of a mapping catheter. In a recently published review, however, only one case of unspecified valve damage was registered among 8745 atrial fibrillation procedures. OBJECTIVE: The purpose of this study was to evaluate patients with entrapment. METHODS: Retrospective analysis of electrophysiological results. RESULTS: We describe three patients with entrapment during ablations for atrial fibrillation. The entrapments occurred with three different operators at three different electrophysiological laboratories within 2 years. The complication described here may be more common than is widely appreciated. CONCLUSIONS: From our figures, we estimate the incidence of the complication to 0.9% (95% confidence interval, 0.2-2.5%).
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| 15. |
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| 16. |
- Kesek, Milos, 1957-
(författare)
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Traces of Repolarization Inhomogeneity in the ECG
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Repolarization inhomogeneity is arrhythmogenic. QT dispersion (QTd) is an easily accessible ECG-variable, related to the repolarization and shown to carry prognostic information. It was originally thought to reflect repolarization inhomogeneity. Lately, arguments have been risen against this hypothesis. Other measures of inhomogeneity are being investigated, such as nondipolar components from principal component analysis (PCA) of the T-wave. In all here described populations, continuous 12-lead ECG was collected during the initial hours of observation and secondary parameters used for description of a large number of ECG-recordings.Paper I studied QTd in 548 patients with chest pain with a median number of 985 ECG-recordings per patient. Paper II explored a spatial aspect of QTd in 276 patients with unstable coronary artery disease. QTd and a derived localized ECG-parameter were compared to angiographical measures. QTd, expressed as the mean value during the observation was a powerful marker of risk. It was however not effective in identifying high-risk patients. Variations in QTd contained no additional prognostic information. In unstable coronary artery disease, QTd was increased by a mechanism unrelated to localization of the disease.Two relevant conditions for observing repolarization inhomogeneity might occur with conduction disturbances and during initial course of ST-elevation myocardial infarction (STEMI). Paper III compared the PCA-parameters of the T-wave in 135 patients with chest pain and conduction disturbance to 665 patients with normal conduction. Nondipolar components were quantified by medians of the nondipolar residue (TWRabsMedian) and ratio of this residue to the total power of the T-wave (TWRrelMedian). Paper IV described the changes in the nondipolar components of the T-wave in 211 patients with thrombolyzed STEMI. TWRabsMedian increased with increasing conduction disturbance and contained a moderate amount of prognostic information. In thrombolyzed STEMI, TWRabsMedian was elevated and has an increased variability. A greater decrease in absolute TWR during initial observation was seen in patients with early ST-resolution. Nondipolar components do however not reflect identical ECG-properties as the ST-elevation and their change does not occur at the same time.
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| 17. |
- Li, Jia-Yi, et al.
(författare)
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Lewy bodies in grafted neurons in subjects with Parkinson's disease suggest host-to-graft disease propagation.
- 2008
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Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1546-170X .- 1078-8956. ; 14, s. 501-503
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Tidskriftsartikel (refereegranskat)abstract
- Two subjects with Parkinson's disease who had long-term survival of transplanted fetal mesencephalic dopaminergic neurons (11-16 years) developed alpha-synuclein-positive Lewy bodies in grafted neurons. Our observation has key implications for understanding Parkinson's pathogenesis by providing the first evidence, to our knowledge, that the disease can propagate from host to graft cells. However, available data suggest that the majority of grafted cells are functionally unimpaired after a decade, and recipients can still experience long-term symptomatic relief.
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| 18. |
- Modin, A., et al.
(författare)
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Closed source experimental system for soft x-ray spectroscopy of radioactive materials
- 2008
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 79:9, s. 093103-
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Tidskriftsartikel (refereegranskat)abstract
- An instrumental and experimental setup for soft x-ray spectroscopy meeting the requirements of a closed source for radioactivity is described. The system consists of a vacuum sealed cell containing the sample, mounted on a tubing system to ensure compatibility with most standard manipulators. The soft x rays penetrate a thin x-ray window separating the interior of the cell from the vacuum in the experimental chamber. Our first results for single crystal PuO2 confirm the feasibility of experiments using the setup. The results are consistent with results of first principles calculations and previously recorded spectra obtained using a standard open source setup. The results show that the closed source experimental system can be used to collect valuable experimental data from radioactive materials.
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| 19. |
- Rapp [Nordin], Erika, et al.
(författare)
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Preference for full-fat over low-fat foods among individuals suffering from coronary heart disease and healthy controls
- 2009
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Ingår i: Physiology and Behavior. - : Elsevier. - 0031-9384 .- 1873-507X. ; 98:4, s. 489-497
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Tidskriftsartikel (refereegranskat)abstract
- Dietary behaviour can modify the risks for coronary heart disease (CHD). Dietary fat contributes to the sensory characteristics of many foods, but there are individual differences in liking for regular and reduced fat products. Preference for dietary fat might differ between healthy individuals and those of diagnosed CHD status. Preference for full-fat versus low-fat foods was assessed in a group suffering from CHD (N = 24) and a healthy control group (N = 41). Preferences were evaluated using a series of paired preference tests including 34 food pairs. Further, patterns across fat preference and a range of known risk factors for CHD were examined. The study was conducted in Sweden; March 2004 until May 2006. Overall the full-fat food items were preferred to the low-fat alternatives by both patients and control participants. The pattern of preference responses diverged significantly between patients and controls on only four of the 34 food items, in both directions, why preference related to total fat content per se is not confirmed as differentiating significantly between a group diagnosed with CHD compared to a healthy control group.
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| 20. |
- Rodhe, Nils, 1951-
(författare)
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Asymptomatic Bacteriuria in the Elderly
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this thesis was to explore the features of asymptomatic bacteriuria (ASB) in elderly people living in the community, and to seek diagnostic tools to discriminate between ASB and symptomatic urinary tract infection (UTI). All men and women aged 80 and over living in an urban district of Falun, Sweden, were invited to participate. Urine samples were obtained together with information on symptoms and on health indicators. The same cohort was surveyed again after 6 and 18 months. Urinary cytokines were analysed in 16 patients with UTI, in 24 subjects with ASB and in 20 negative controls. ASB occurred at baseline in 19.0% of women and 9.4% of men, and was found at least once in 36.9% of women and in 20.2% of men. ASB in women was associated with reduced mobility and urge urinary incontinence. Of those with ASB at baseline, 60% still had bacteriuria at 6 and 18 months, but among those with repeated findings of ASB with E. coli, only 40% had the same bacterial strain after 18 months. In women, the risk of developing a UTI within 24 months was higher among those with ASB at baseline than in those without. Urinary levels of cytokines (CXCL1, CXCL8 and IL-6) and leukocyte esterase were higher in patients with UTI than in patients with ASB. There is convincing evidence that ASB is harmless and should not be treated with antibiotics. However, such treatment is still often given, thereby unnecessarily contributing to the increased number of bacteria resistant to common antibiotics. This study confirms the high prevalence of ASB in elderly people living in the community. In order not to be misled by a urinary test showing bacteria, it is important to restrict urinary testing for bacteria to patients where there is a suspicion of UTI. In elderly patients with diffuse symptoms or in patients who are unable to communicate their symptoms, further diagnostic help could possibly be obtained by evaluating the urinary levels of leukocyte esterase and/or IL-6.
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| 21. |
- Strömbeck, Britta, et al.
(författare)
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Patients with ankylosing spondylitis have increased sick leave—a registry-based case-control study over 7 yrs
- 2009
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Ingår i: Rheumatology. - Oxford : Oxford University Press. - 1462-0324 .- 1462-0332. ; 48:3, s. 289-292
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Using prospectively collected registry data to investigate sick leave (sickness benefit and sickness compensation) over a 7-yr period in patients with AS in comparison with population-based controls matched for age, sex and residential area.METHODS: We investigated 122 (21 women and 101 men) outpatients with AS in South Sweden, born 1942 or later, from rheumatology specialist care for their sick leave during a 7-yr period. Mean (S.D.) age was 43 (11) yrs and mean (S.D.) disease duration was 20 (11) yrs. Two controls per case, matched for age, sex and residential area were selected from the Swedish National Population Register. Data concerning sick leave for cases and controls, based on the subjects' unique 10-digit personal identification number, were retrieved from the national register of the Swedish Social Insurance Agency.RESULTS: More AS patients than controls were registered for sickness benefit (52 vs 36%, P < 0.01) and sickness compensation (42 vs 11%, P < 0.001). Cases had an increased risk for sick leave compared with controls with a relative risk of 1.8; 95% CI 1.5, 2.1; and cases had more days with sick leave than controls (median number of more days per year 30; 95% CI 2, 72).CONCLUSIONS: Using the Swedish Social Insurance Agency's registers for sick leave, we found that patients with AS in rheumatology specialist care in South Sweden have an increased level of sick leave compared with controls. These population-based registers have a great potential for studies of the effects of different interventions on sick leave. © 2009 The Author(s).
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| 22. |
- Svensson, Per-Arne, 1969, et al.
(författare)
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Regulation and splicing of scavenger receptor class B type I in human macrophages and atherosclerotic plaques
- 2005
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Ingår i: BMC Cardiovasc Disord. - : Springer Science and Business Media LLC. - 1471-2261. ; 5
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The protective role of high-density lipoprotein (HDL) in the cardiovascular system is related to its role in the reverse transport of cholesterol from the arterial wall to the liver for subsequent excretion via the bile. Scavenger receptor class B type I (SR-BI) binds HDL and mediates selective uptake of cholesterol ester and cellular efflux of cholesterol to HDL. The role of SR-BI in atherosclerosis has been well established in murine models but it remains unclear whether SR-BI plays an equally important role in atherosclerosis in humans. The aim of this study was to investigate the expression of SR-BI and its isoforms in human macrophages and atherosclerotic plaques. METHODS: The effect of hypoxia and minimally modified low-density lipoprotein (mmLDL), two proatherogenic stimuli, on SR-BI expression was studied in human monocyte-derived macrophages from healthy subjects using real-time PCR. In addition, SR-BI expression was determined in macrophages obtained from subjects with atherosclerosis (n = 15) and healthy controls (n = 15). Expression of SR-BI isoforms was characterized in human atherosclerotic plaques and macrophages using RT-PCR and DNA sequencing. RESULTS: SR-BI expression was decreased in macrophages after hypoxia (p < 0.005). In contrast, SR-BI expression was increased by exposure to mmLDL (p < 0.05). There was no difference in SR-BI expression in macrophages from patients with atherosclerosis compared to controls. In both groups, SR-BI expression was increased by exposure to mmLDL (p < 0.05). Transcripts corresponding to SR-BI and SR-BII were detected in macrophages. In addition, a third isoform, referred to as SR-BIII, was discovered. All three isoforms were also expressed in human atherosclerotic plaque. Compared to the other isoforms, the novel SR-BIII isoform was predicted to have a unique intracellular C-terminal domain containing 53 amino acids. CONCLUSION: We conclude that SR-BI is regulated by proatherogenic stimuli in humans. However, we found no differences between subjects with atherosclerosis and healthy controls. This indicates that altered SR-BI expression is not a common cause of atherosclerosis. In addition, we identified SR-BIII as a novel isoform expressed in human macrophages and in human atherosclerotic plaques.
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| 23. |
- Synnergren, Jane, 1967, et al.
(författare)
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Cardiomyogenic gene expression profiling of differentiating human embryonic stem cells.
- 2008
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Ingår i: Journal of biotechnology. - : Elsevier BV. - 0168-1656 .- 1873-4863. ; 134:1-2, s. 162-70
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Tidskriftsartikel (refereegranskat)abstract
- Human embryonic stem cells (hESCs) can differentiate into a variety of specialized cell types. Thus, they provide a model system for embryonic development to investigate the molecular processes of cell differentiation and lineage commitment. The development of the cardiac lineage is easily detected in mixed cultures by the appearance of spontaneously contracting areas of cells. We performed gene expression profiling of undifferentiated and differentiating hESCs and monitored 468 genes expressed during cardiac development and/or in cardiac tissue. Their transcription during early differentiation of hESCs through embryoid bodies (EBs) was investigated and compared with spontaneously differentiating hESCs maintained on feeders in culture without passaging (high-density (HD) protocol). We observed a larger variation in the gene expression between cells from a single cell line that were differentiated using two different protocols than in cells from different cell lines that were cultured according to the same protocol. Notably, the EB protocol resulted in more reproducible transcription profiles than the HD protocol. The results presented here provide new information about gene regulation during early differentiation of hESCs with emphasis on the cardiomyogenic program. In addition, we also identified regulatory elements that could prove critical for the development of the cardiomyocyte lineage.
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| 24. |
- Synnergren, Jane, 1967, et al.
(författare)
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Differentiating human embryonic stem cells express a unique housekeeping gene signature.
- 2007
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Ingår i: Stem cells (Dayton, Ohio). - : Oxford University Press (OUP). - 1066-5099 .- 1549-4918. ; 25:2, s. 473-80
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Tidskriftsartikel (refereegranskat)abstract
- Housekeeping genes (HKGs) are involved in basic functions needed for the sustenance of the cell and are assumed to be constitutively expressed at a constant level. Based on these features, HKGs are frequently used for normalization of gene expression data. In the present study, we used the CodeLink Gene Expression Bioarray system to interrogate changes in gene expression occurring during differentiation of human ESCs (hESCs). Notably, in the three hESC lines used for the study, we observed that the RNA levels of 56 frequently used HKGs varied to a degree that rendered them inappropriate as reference genes. Therefore, we defined a novel set of HKGs specifically for hESCs. Here we present a comprehensive list of 292 genes that are stably expressed (coefficient of variation <20%) in differentiating hESCs. These genes were further grouped into high-, medium-, and low-expressed genes. The expression patterns of these novel HKGs show very little overlap with results obtained from somatic cells and tissues. We further explored the stability of this novel set of HKGs in independent, publicly available gene expression data from hESCs and observed substantial similarities with our results. Gene expression was confirmed by real-time quantitative polymerase chain reaction analysis. Taken together, these results suggest that differentiating hESCs have a unique HKG signature and underscore the necessity to validate the expression profiles of putative HKGs. In addition, this novel set of HKGs can preferentially be used as controls in gene expression analyses of differentiating hESCs.
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| 25. |
- Synnergren, Jane, et al.
(författare)
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Differentiating human embryonic stem cells express a unique housekeeping gene signature
- 2006
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Ingår i: 4th ISSCR Annual Meeting.
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Konferensbidrag (refereegranskat)abstract
- Human embryonic stem cells (hESCs) represent populations of pluripotent undifferentiated cells with unlimited replication capacity which can be coaxed to differentiate into a variety of specialized cells. As a result, there is great hope that hESCs will be extremely useful by providing platforms for various in vitro applications (e.g. in drug discovery) as well as for future use of hESCs and their differentiated progeny in cell replacement therapies. In order to realize the potential of hESCs, it is necessary to gain much deeper knowledge about the processes that govern differentiation of these cells.In recent years, significant progress towards understanding cellular differentiation has been fuelled, in part, by studying gene expression using microarrays. In this large scale studies, statistical methods are used to normalize the gene expression data and render comparisons between different samples. In lower throughput analyses, RNA levels in hESCs are also measured using RT-PCR requiring normalization of the gene expression data to adequately correct for inter-sample variation. In general, investigators have used the traditional housekeeping genes (HKGs) (e.g. GAPDH, b-tubulin, b-actin) in studies of hESCs. HKGs are involved in basic functions needed for the sustenance of the cell and are assumed to be constitutively expressed at a constant level. Based on these features, HKGs are frequently used for normalization of gene expression data. However, it is well known that the expression of several of these genes vary considerably in adult tissues and their suitability as HKGs in hESCs remains to be proven. In this regard, the RNA levels of HPRT and b-tubulin were shown to vary substantially in differentiating mouse ESCs.In the present study, we used the CodeLinkTM Gene Expression Bioarray system to interrogate changes in gene expression occurring during differentiation of hESCs. Notably, in the three hESC lines used for the study, we observed that the RNA levels of 56 frequently used HKGs varied to a degree that rendered them inappropriate as reference genes. Therefore, we defined a novel set of HKGs specifically for hESCs. Here we present a comprehensive list of 292 genes that are stably expressed (coefficient of variation<20%) in differentiating hESCs. These genes were further grouped into high, medium, and low expressed genes. The expression patterns of these novel HKGs show very little overlap with results obtained from somatic cells and tissues. We further explored the stability of this novel set of HKGs in independent, publicly available gene expression data from hESCs and observed substantial similarities in terms of stably expressed genes. Taken together, these results suggest that hESCs have a unique HKG signature and underscore the necessity to validate the expression profiles of putative HKGs. In addition, the novel set of identified HKGs can preferentially be used as controls in gene expression analyses of differentiating hESCs.
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