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J Wikström

Publications and source records attributed to J Wikström.

At least 19 recordsLinked to original sources
PubMed2006

The prevalence and quantification of atherosclerosis in an elderly population assessed by whole-body magnetic resonance angiography.

OBJECTIVE: The principal aim of the present study was to explore the feasibility of using whole-body magnetic resonance angiography to assess atherosclerosis in different vascular territories in a cohort of elderly. METHODS AND RESULTS: Three hundred six 70-year-old subjects (145 women, 161 men) recruited from a population-based cohort study (Prospective Investigation of the Vasculature in Uppsala Seniors, ie, the PIVUS study) underwent 1.5-T whole-body magnetic resonance angiography with gadodiamide. The arteries were divided into 26 segments. In total, 7956 vessel segments were evaluated with 7900 segments (99.3%) possible to evaluate. Of these, 7186 segments (91%) were normal. Luminal narrowing of > or = 50% was observed in 9 (1.5%) of the renal arteries, 12 (1.8%) of the carotid arteries, in 31 segments (1.1%) of the pelvic/upper leg territories, and in 136 segments (6.2%) of territories in the lower leg. Approximately one-third of the sample had no vascular abnormalities, one-third had stenoses of < 50%, and the remainder had stenoses > or = 50% or occlusions. Six subjects (2%) had aortic aneurysms. In subjects without evident vascular disease, 26% had significant vascular abnormalities. CONCLUSIONS: Whole-body magnetic resonance angiography performed with a clinical scanner can be used for quantifying atherosclerosis in different vascular territories in a single examination in an elderly population.

Age Distribution↗
PubMed2006

Random albumin/creatinine ratio for quantification of proteinuria in manifest pre-eclampsia.

OBJECTIVE: 1) To assess the correlation between urine albumin/creatinine ratio (ACR) and 24-hour urine albumin excretion in women with pre-eclampsia, 2) to study the influence of potential confounders on this correlation and 3) to assess the variability of ACR between voids during a 24-hour period. DESIGN: Prospective study. SETTING: Fetal maternity ward, university hospital. POPULATION: Women with pre-eclampsia scheduled for quantitative albumin measurement with a 24-hour urine collection. METHODS: Random urine samples were obtained for analysis of ACRs during the time of 24-hour urine collections in 31 women. ACRs were also measured from the complete 24-hour collections. In five additional women, serial urine samples were obtained during the 24-hour collection. MAIN OUTCOME MEASURES: Correlation between ACRs and albumin amount in 24-hour urine samples. Variability of the ACRs during a 24-hour collection. RESULTS: The random ACR was poorly correlated to 24-hour excretion of urine albumin (R(2)= 0.42). Adjustment for maternal age and nifedipine medication significantly (P= 0.044 and P= 0.023, respectively) improved the correlation (R(2)= 0.60). The mean variability (highest/lowest) of ACR during a 24-hour period was 222%. The ACR from the 24-hour collection had an excellent correlation to 24-hour excretion of urine albumin (R(2)= 0.96). CONCLUSIONS: In women with pre-eclampsia, random ACR is not stable during the day and cannot predict 24-hour urine protein excretion accurately. ACR from the 24-hour collection is an accurate predictor of total albumin amount and can be used to minimise errors from incomplete collections.

Albuminuria↗
PubMed2006

Parallel gene expressions of IL-6 and BNP during cardiac hypertrophy complicated with diastolic dysfunction in spontaneously hypertensive rats.

UNLABELLED: There is increasing evidence showing that inflammation is involved in heart failure. However, heart failure may differ greatly due to different aetiologies. The role of inflammation in hypertensive heart failure, particularly in the early stage of cardiac dysfunction, has not been studied completely. This study aims at finding out whether inflammation is involved in the early stage of heart dysfunction due to hypertension. METHODS: Ten spontaneously hypertensive rats (SHR) and ten age-matched Wistar rats were used. Cardiac morphology and function, as well as coronary flow reserve, were examined by echocardiography. mRNAs for cytokines and brain natriuretic peptide were determined by RT-PCR. RESULTS: The results demonstrate cardiac hypertrophy with increased heart/body weight ratio in SHR. Echocardiographic examination has shown that SHR developed diastolic heart dysfunction as determined by tissue Doppler without decrease in systolic function. In heart biopsies, there were increased mRNA levels for interleukin-6 and brain natriuretic peptide whereas decreased mRNA for interleukin-2, beta adrenergic receptor, interferon and NFkb in SHR as compared to WKY group. Coronary flow remained unchanged in both groups. CONCLUSION: SHR developed cardiac hypertrophy complicated with diastolic heart dysfunction with increased expression of brain natriuretic peptide, down-regulation of beta adrenergic receptors and simultaneous up-regulation of IL-6, which indicates active proinflammatory process as, at least partly, underlying mechanism during the early stage when cardiac hypertrophy associated with diastolic dysfunction occurs.

Animals↗
PubMed2004

A two-stage study on multiple sclerosis susceptibility and chromosome 2q33.

We have performed a two-stage study to analyse the association of polymorphism on chromosome 2q33 with multiple sclerosis (MS). In all, 17 markers were analysed in stage-1 in 134 Finnish MS families and the observed associations were tested in stage-2 in 186 MS families. We did not find previously reported allelic or haplotype associations with CTLA4. We obtained a weak signal of two distinct predisposing genes, one proximal the other distal of CTLA4. The putative proximal gene was associated with the marker rs3977 in families lacking HLA-DR2 (P=0.02 and 0.02) and the other distal gene was associated with D2S1271 in families from a high-risk region in western Finland (P=0.02 and 0.01). Based on the >3 cM distance and the lack of linkage disequilibrium between these loci, we conclude that the two association signals are independent. Our results provide preliminary evidence for two distinct MS susceptibility genes on 2q33 outside of CTLA4.

Antigens, CD↗
PubMed2004

Occurrence of multiple sclerosis in central Finland: a regional and temporal comparison during 30 years.

OBJECTIVE: We estimated the prevalence and incidence of multiple sclerosis (MS) in central Finland up to 2000. Rates were compared with those in other areas in Finland. MATERIAL AND METHOD: MS cases were identified in the hospital registry by ICD codes for demyelinating diseases from 1979 to 2000. Cases with definite MS were included. Incidence and prevalence were calculated with 95% CI and standardization was performed using direct method. RESULTS: In 1993 prevalence was 59/10(5) (n = 153). Incidence in 1979-93 was 3.8/10(5) person-years (n = 126). Rates are similar to average in areas with known rates of MS in Finland but substantially less than the over twofold MS risk in the neighbouring district Seinajoki. Extended follow-up to 2000 in central Finland showed increasing prevalence up to 105/10(5) (n = 277) and a significant increase in incidence 1994-98 up to 9.2/10(5) (n = 105). At the same time the diagnostic use of MRI increased up to 97%. CONCLUSION: Central Finland represents an average risk area of MS when compared with other areas of Finland but still a high risk in global comparison. The recent rapid increase in both prevalence and incidence is largely accounted for by increased use of MRI.

Adolescent↗
PubMed2003

Linkage disequilibrium between the MBP tetranucleotide repeat and multiple sclerosis is restricted to a geographically defined subpopulation in Finland.

We have previously found evidence for linkage as well as allelic and haplotype association between the myelin basic protein (MBP) gene and multiple sclerosis (MS). These findings have, however, not been reproduced in other populations. Here, we have analyzed association between MBP and MS in a new set of 349 Finnish triad families. Families with a parent born in the Southern Ostrobothnian region in western Finland (Bothnia families, n=98) were analyzed as a separate group since our previous studies included a high proportion of patients and families from this high-incidence region. Other families (n=251) were collected at five hospitals in southern, eastern, and northern Finland. The MBP short tandem repeat was genotyped, and haplotype patterns were verified by sequencing. In the Bothnia families, the previously detected associations with the 1.27 kb allele and haplotype 1.27-B10 were confirmed (P=0.01 and 0.02, respectively), whereas in the other families there was not even a trend toward association. These results demonstrate a geographic/genealogical restriction in the association between MS and the MBP short tandem repeat, highlight the importance of genealogical information in genetic studies of complex traits, and may provide an explanation why the association has not been found in many other populations.

Alleles↗
PubMed2003

Multiple sclerosis in Finland: incidence trends and differences in relapsing remitting and primary progressive disease courses.

OBJECTIVE: To compare the secular trends and geographical differences in the incidence of relapsing-remitting (RRMS) and primary progressive multiple sclerosis (PPMS) in Finland, and to draw inferences about aetiological differences between the two forms of the disease. METHODS: New multiple sclerosis cases in southern Uusimaa and the western districts Vaasa and Seinäjoki of Finland in 1979-1993 were verified from hospital records and classified into RRMS and PPMS. Patients met the Poser criteria for definite multiple sclerosis or otherwise satisfied the criteria for PPMS. Disease course was categorised by the same neurologist. Crude and age adjusted incidence in 1979-1993 was estimated. RESULTS: During 1979-1993 the age adjusted incidence was 5.1 per 100 000 person-years in Uusimaa, 5.2 in Vaasa, and 11.6 in Seinäjoki. The rates in Uusimaa remained stable, while a decrease occurred in Vaasa and an increase in Seinäjoki. Between 1979-86 and 1987-93 the incidence of PPMS increased in Seinäjoki from 2.6 to 3.7 per 10(5) and decreased in Vaasa from 1.9 to 0.2 per 10(5); the trends were similar for RRMS. CONCLUSIONS: There are significant differences in secular trends for multiple sclerosis incidence in Finland by geographical area, but these are similar for PPMS and RRMS. The recent changes point to locally acting environmental factors. The parallel incidence trends for RRMS and PPMS suggest similar environmental triggers for the two clinical presentations of multiple sclerosis.

Adolescent↗
PubMed2002

The importance of adjusting for differences in proximal and distal contrast bolus arrival times in contrast-enhanced iliac artery magnetic resonance angiography.

We tested the hypothesis that differences in proximal and distal contrast bolus arrival times may result in insufficient vascular signal in the distal part of the aortoiliofemoral territory with routinely used timing techniques. The difference in arrival time of the contrast medium bolus between the aorta and the common femoral arteries was measured in 14 patients undergoing magnetic resonance angiography of the aortoiliac arteries. A dual-station test bolus technique adjusting for this difference was evaluated. The variation coefficient of the signal intensity in six defined locations and signal intensities (SI) normalised to fat were calculated. Comparisons were made with findings in 13 patients examined with a fluoroscopically triggered timing technique (BolusTrak, Philips Medical Systems, Best, The Netherlands). The difference in bolus arrival time between proximal and distal vessels was 0-7 s. In 3 of 14 patients it was 5.6-7 s. There was a tendency towards a lower mean variation coefficient in the dual-station group ( p=0.10). With both techniques, significantly lower SIs were measured in the femoral arteries compared with SIs in the superior part of the abdominal aorta. In two cases in the BolusTrak group, a distal vessel could not be delineated but was shown to be patent on a delayed scan. Differences in contrast medium arrival time along the vessel may be large enough to preclude visualisation of distal vessels unless there is compensation. A dual-station test bolus technique taking this into account was found to be feasible.

Adult↗
PubMed2002

Chromosome 19q13 and multiple sclerosis susceptibility in Finland: a linkage and two-stage association study.

Several studies have previously provided some albeit weak evidence for linkage or association between chromosome 19q13 and multiple sclerosis (MS) susceptibility. We performed a two-stage association analysis with 19 markers spanning 7 Mb/5.5 cM of 19q13. In stage 1 analysis (135 MS families) allelic and haplotypic associations were found with markers within or close to the ApoE-ApoC subregion. These observations were taken as a hypothesis, which was tested in stage 2 in 125 families. However, none of the initial associations were replicated suggesting that they were most likely due to chance. Linkage analysis was performed in 27 Finnish multiplex families using 10 microsatellites spanning 23 Mb/24 cM of 19q13. DNA was available from 72 MS patients and 150 unaffected relatives. Parametric and non-parametric linkage analyses did not provide evidence for linkage when all families were tested. After stratifying the families according to HLA-DR15 there was weak evidence for linkage to the 19q13.1 subregion in DR15 negative families (LOD(max)=1.8). Taken together these results do not support a major role of chromosome 19q13.2-q13.3 in MS susceptibility among Finnish MS patients, whereas conclusions on the 19q13.1 subregion are less clear and this region requires further study.

Adolescent↗
PubMed2002

High-resolution carotid artery MRA. Comparison with fast dynamic acquistion and duplex ultrasound scanning.

PURPOSE: To determine whether the diagnostic accuracy of contrast-enhanced MR angiography (CE-MRA) of the carotid arteries is improved by using a slow-injection, high-resolution technique. MATERIAL AND METHODS: In 22 patients suspected to have internal carotid artery (ICA) stenosis at duplex ultrasound scanning (DUS), CE-MRA was performed both with a fast, dynamic (8 s/phase) and with a slower, high-resolution technique (scan time 2:20 min). RESULTS: There was conformity between the CE-MRA techniques regarding the degree of stenosis in 34/40 extracranial ICAs. In 3/6 discrepant cases, short occlusions were seen with the fast dynamic technique, whereas both the high-resolution CE-MRA technique and DUS showed patent vessels. There was an overall tendency toward higher stenosis grading with the dynamic technique. Overlying veins could be removed on a workstation in all high-resolution examinations. CONCLUSION: The high-resolution carotid CE-MRA technique proposed herein seems to improve the diagnostic accuracy, at least for differentiation between high-grade stenoses and occlusions.

Carotid Artery, Internal↗
PubMed2002

Survival of multiple sclerosis in Finland between 1964 and 1993.

The long-term survival of multiple sclerosis (MS) was studied during 1964-1993 in a cohort of 1614 patents in Finland. Survival to death from the initial MS symptoms was analysed by the life-table method, separately for MS related and all causes of deaths. Survival at 40 years was 64% for MS deaths and 53% for all deaths. Higher proportions of violent deaths and neoplasms were observed among MS patients as compared to the general population, whereas the proportion of cardiovascular causes of death was low. MS-related causes accounted for 70% of the recorded 219 deaths. Favourable survival in MS was associated with relapsing-remitting disease course, age at onset below 30 years and optic neuritis or other sensory symptoms at presentation. We were unable to show any significant effect due to calendar time of diagnosis or gender, as the risk of men was similar (risk ratio [RR] = 1.1, confidence interval [CI] 0.8-1.6) as compared to women.

Adult↗
PubMed2001

Increasing prevalence of multiple sclerosis in Finland.

OBJECTIVES: To follow-up the prevalence trends of MS from 1983 to 1993 in western and southern Finland. MS epidemiology has been previously followed from 1964 to 1978 in these regions. The updated prevalences were correlated with incidence trends in the same period. METHODS: Age-adjusted and age-specific MS prevalence rates were calculated for cases classified by Poser's criteria. RESULTS: In the western health-care districts, Seinäjoki and Vaasa, prevalences in 1993 were 202/10(5) and 111/10(5). In the southern district Uusimaa the respective figure was 108/10(5). In Seinäjoki a significant 1.7-fold increase was found in 1993 as compared to 1983, mainly due to increased incidence. In Uusimaa a significant 1.2-fold increase in prevalence was found in the presence of stable incidence. In Vaasa prevalence was stable, although incidence was declining. CONCLUSION: The prevalence of MS is increasing in Seinäjoki and Uusimaa but not in Vaasa. Both the prevalence and incidence in Seinäjoki are now among the highest reported.

Adolescent↗
PubMed2001

On contrast-enhanced magnetic resonance angiography of the aortoiliac arteries.

In contrast-enhanced MR angiography (CE-MRA), vascular signal is produced by the acquisition of a T1-weighted MR imaging scan while the presence of a contrast agent induces a low T1 in blood. In this thesis, CE-MRA of the aortoiliac arteries was evaluated. Different contrast agents and techniques for synchronisation of the scan with the contrast bolus passage were assessed. In 30 patients with clinically suspected iliac artery stenoses, CE-MRA was compared with duplex ultrasound scanning (DUS) and digital subtraction X-ray angiography (DSA), with intra-arterial pressure measurements as reference. No statistically significant differences in sensitivity or specificity were observed between the techniques regarding detection of haemodynamically significant iliac stenoses. The use of multiplanar reformat and source images in the MRA examinations was of value for differentiation between highgrade stenoses and occlusions. With DSA as reference method, MRA had significantly higher sensitivity and specificity than DUS for detection of > or = 50% stenoses. In 14 patients who underwent iliac artery MRA, differences in contrast arrival time of up to 7 s were observed between the aorta and the common femoral artery. A dual-station timing technique adjusting for this difference was found feasible. Compared with a fluoroscopically triggered technique (n = 13), which is used in clinical routine, the dual-station technique was more reliable for the visualisation of distal vessels. In a clinical phase II study comparing doses of the contrast agent gadobenate dimeglumine from 0.0125 to 0.2 mmol/kg b.w. for enhancement of iliac artery MRA, significant improvement in subjective diagnostic quality compared with time-of-flight-MRA was found at all doses from 0.025 mmol/kg b.w. An increasing trend with dose was observed up to a dose of 0.05-0.1 mmol/kg b.w. In a phase I clinical study on the intravascular iron oxide contrast agent NC100150 Injection, a positive dose response was observed for abdominal vascular enhancement, with the highest contrast-to-noise ratio observed at 4.0 mg Fe/kg b.w. at 1.5 T and at 2.5-4 mg Fe/kg b.w. at 0.5 T. At 1.5 T higher calculated R2* values were found for the aorta than for the inferior vena cava.

Academic Dissertations as Topic↗
PubMed2000

Gadolinium-enhanced magnetic resonance angiography, digital subtraction angiography and duplex of the iliac arteries compared with intra-arterial pressure gradient measurements.

PURPOSE: to compare gadolinium-enhanced magnetic resonance angiography (Gd-MRA), digital subtraction angiography (DSA) and duplex of the iliac arteries with intra-arterial pressure gradient measurement as the reference method. MATERIALS AND METHODS: Gd-MRA, DSA and duplex examinations of the iliac arteries were performed in 30 patients (60 arteries) with lower-limb arterial occlusive disease. In 29 arteries, pressure measurements were made (n=25) or the artery was found to be occluded on catheterisation (n=4). An aortofemoral peak systolic pressure gradient of 20 mmHg or more was regarded as haemodynamically significant. Stenoses with a diameter reduction of 50% or more on MRA or DSA, or an increase in peak systolic velocity greater than 150% (duplex) were considered significant. MRA examinations were evaluated by means of maximum intensity projections (MRA-MIP) and using source images and curved multiplanar reconstruction (MRA-MPR). RESULTS: the sensitivity (specificity) for a significant iliac artery stenosis were 81% (75%) for MRA-MIP, 76% (75%) for MRA-MPR, 86% (88%) for DSA, and 72% (88%) for duplex. CONCLUSION: with intra-arterial pressure measurements as the reference method, similar results were achieved with Gd-MRA, DSA and duplex concerning the detection of haemodynamically significant iliac artery stenoses. The use of source images and multiplanar reconstructions resulted in higher accuracy for the detection of occlusions.

Aged↗
PubMed1999

Preattentive bias for emotional information in panic disorder with agoraphobia.

A combined emotional Stroop and implicit memory (tachistoscopic identification) task with 3 types of words (panic-related, interpersonal threat, and neutral words) and 2 exposure conditions (subliminal, supraliminal) was administered to 35 patients with panic disorder and 35 age- and sex-matched controls. The patients showed Stroop interference for panic-related words both sub- and supraliminally and a similar but not equally robust effect on interpersonal threat words. On the tachistoscopic identification task, the patients identified more panic-related words than the controls did but showed no implicit memory bias effect. The patients' subliminal Stroop interference for panic-related words was found to correlate with trait anxiety and depression, although not with anxiety sensitivity.

Adult↗
PubMed1998

Golli-MBP gene in multiple sclerosis susceptibility.

Multiple sclerosis (MS) is an oligo- or polygenic disease but no specific susceptibility genes have been identified so far. In the Finnish population we have previously found evidence for linkage between MS and the myelin basic protein gene (here called Golli-MBP gene) suggesting that either Golli-MBP or another gene in its vicinity contributes to MS suceptibility. Here we have screened the Golli-MBP gene for nucleotide variations and carried out multipoint association analyses in a Finnish case-control data-set as well as in an independent data-set composed of 151 MS families from Finland and Sweden. In both data-sets we found association between MS and alleles in the 1.27 kilobase (kb) range at a tetranucleotide repeat element (TGGA)n which is located 1 kb upstream of the MBP exon 1. Haplotype analyses suggested that the MS-associated 1.27 kb alleles can be split into predisposing and non-predisposing variants and provided evidence that the candidate DNA region contributing to MS susceptibility should be located at the Golli-MBP gene within a 20-25 kb segment that was conserved in the predisposing haplotypes. These findings suggest a role for the Golli-MBP locus in MS susceptibility, at least in a subset of patients, and serve as a basis for highly focused attempts to identify predisposing mutation(s).

Adult↗
PubMed1997

Immune system genes in multiple sclerosis: genetic association and linkage analyses on TCR beta, IGH, IFN-gamma and IL-1ra/IL-1 beta loci.

The role of genetic factors in the etiology of multiple sclerosis (MS) has been clearly demonstrated but the loci determining susceptibility to this disease remain largely unidentified. A contribution from several immune system genes has been suggested based on animal models and association/linkage analyses on MS patients and families. With the exception of the findings from the HLA complex, studies on candidate immune system genes have provided controversial results. Here we have performed genetic association and linkage analyses on four chromosomal regions containing immune system genes. A possible role for each of these loci in MS has been previously suggested. In data-sets derived from the Finnish population we found no evidence for contribution of the T-cell receptor beta chain (TCR beta chromosome 7q35), immunoglobulin heavy chain (IGH chromosome 14q32), interferon-gamma (IFN-gamma chromosome 12q14-q15) or interleukin-1 receptor antagonist/interleukin-1 beta (IL-1ra/IL-1 beta chromosome 2q14-q21) loci in the genetic susceptibility to MS.

Adult↗