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  • 1.
    Acosta, Stefan
    et al.
    Vascular Center, Malmö University Hospital, Malmö, Sweden.
    Block, Tomas
    Department of Surgical Sciences, Vascular Surgery, Uppsala University, Uppsala, Sweden.
    Björnsson, Steinarr
    Vascular Center, Malmö University Hospital, Malmö, Sweden.
    Resch, Timothy
    Vascular Center, Malmö University Hospital, Malmö, Sweden.
    Björck, Martin
    Department of Surgical Sciences, Vascular Surgery, Uppsala University, Uppsala, Sweden.
    Nilsson, Torbjörn
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Clinical Chemistry, Örebro University Hospital, Örebro, Sweden.
    Diagnostic pitfalls at admission in patients with acute superior mesenteric artery occlusion2012In: Journal of Emergency Medicine, ISSN 0736-4679, E-ISSN 1090-1280, Vol. 42, no 6, p. 635-641Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Acute superior mesenteric artery (SMA) occlusion leads to acute intestinal ischemia and is associated with high mortality. Early diagnosis is often missed, and confounding factors leading to diagnostic delays need to be highlighted.

    OBJECTIVES: To identify potential diagnostic laboratory pitfalls at admission in patients with acute SMA occlusion.

    METHODS: Fifty-five patients with acute SMA occlusion were identified from the in-hospital register during a 4-year period, 2005-2009.

    RESULTS: The median age was 76 years; 78% were women. The occlusion was embolic in 53% and thrombotic in 47% of patients. At admission, troponin I was above the clinical decision level (> 0.06 μg/L) for acute ischemic myocardial injury in 9/19 (47%) patients with embolic occlusion. Elevated pancreas amylase and normal plasma lactate were found in 12/45 and 13/27, respectively. A troponin I (TnI) above the clinical decision level was associated with a high frequency of referrals from the general surgeon to a specialist in internal medicine (p = 0.011) or a cardiologist (p = 0.024). The diagnosis was established after computed tomography angiography in 98% of the patients. The overall in-hospital mortality rate was 33%. Attempting intestinal revascularization (n = 43; p < 0.001), with a 95% frequency rate of completion control of the vascular procedure, was associated with a higher survival rate, whereas referral to the cardiologist was associated with a higher mortality rate (p = 0.018).

    CONCLUSION: Elevated TnI was common in acute SMA occlusion, and referral to the cardiologist was found to be associated with adverse outcome. Elevated pancreas amylase and normal plasma lactate values are also potential pitfalls at admission in patients with acute SMA occlusion.

  • 2.
    Acosta, Stefan
    et al.
    Vascular Center, Skåne University Hospital, Malmö, Sweden.
    Nilsson, Torbjörn
    Department of Clinical Chemistry, Örebro University Hospital, Örebro, Sweden.
    Current status on plasma biomarkers for acute mesenteric ischemia2012In: Journal of Thrombosis and Thrombolysis, ISSN 0929-5305, E-ISSN 1573-742X, Vol. 33, no 4, p. 355-361Article in journal (Refereed)
    Abstract [en]

    Clinical diagnosis of acute mesenteric ischemia is difficult. The aim of this review is to provide current status on the search for an accurate plasma biomarker for acute mesenteric ischemia. A search using the medical subject heading terms marker and mesenteric ischemia or intestinal ischemia or superior mesenteric artery occlusion or mesenteric venous thrombosis in the Medline and Embase databases from 1980 to 2011. Studies without a control group or a control group consisted of healthy individuals (human studies), or studies on intestinal reperfusion were excluded. Twenty animal and twelve human studies were identified. In human studies, the studied series of patients had a control group that had a need of laparotomy (n = 2), suspected acute mesenteric ischemia (n = 7), acute abdomen (n = 2) or systemic inflammatory response syndrome (n = 1). D: -dimer has been found to be the most consistent highly sensitive early marker, but specificity was low. The follow-up study on α-glutathione S-transferase yielded inferior sensitivity and accuracy than the preliminary study, clearly questioning the value of this marker. Intestinal fatty acid binding globulin (I-FABP) and D: -lactate are both interesting markers, but the results were conflicting. Different cut-off levels have been used in the studies on I-FABP. The encouraging preliminary result of cobalt-albumin and urinary FABP as an accurate marker needs to be addressed in other study populations. The early clinical and laboratory diagnosis of intestinal ischemia remains a challenge. None of the proposed plasma-derived tests for acute mesenteric ischemia has as yet entered routine clinical practice. The proposed biomarkers need to be evaluated in a prospective clinical research project in patients with acute abdomen.

  • 3. Acosta, Stefan
    et al.
    Nilsson, Torbjörn K
    Örebro University, School of Health and Medical Sciences.
    Malina, Janne
    Malina, Martin
    L-lactate after embolization of the superior mesenteric artery2007In: Journal of Surgical Research, ISSN 0022-4804, E-ISSN 1095-8673, Vol. 143, no 2, p. 320-328Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Plasma markers for intestinal ischemia have not proven to be accurate. The value of L-lactate is unclear. Experimental models based on open surgery confound the effects of surgical trauma with that of ischemia. The aim was to create an endovascular model for acute superior mesenteric artery thromboembolism, and then to study L-lactate and lactate dehydrogenase (LD) activity in plasma and peritoneal fluid in pigs with extensive, high-grade intestinal ischemia. MATERIALS AND METHODS: Nine pigs underwent full superior mesenteric artery embolization with 4 h of intended intestinal ischemia, whereas six were control animals. Sampling of central venous and arterial blood was performed throughout the experiment, ending with laparotomy to collect peritoneal fluid and segmental intestinal biopsies. A pathologist, blinded to the performed interventions, graded the ischemic lesions. RESULTS: There were no differences in plasma L-lactate (P = 0.61) or LD activity levels (P = 0.69), measured at different time points from baseline to end of study, between animals with extensive, high-grade intestinal ischemia and sham. Intraperitoneal L-Lactate (P = 0.005) and LD activity (P = 0.018) levels were elevated compared with sham. There were differences in grades of ischemia in the duodenum (P = 0.003), small intestine (P < 0.001), proximal (P < 0.001), and sigmoid (P = 0.032) colon between experimental animals and sham. The grade of small bowel ischemia (n = 15) correlated to intraperitoneal fluid L-lactate (r = 0.80; P < 0.001) and LD activity levels (r = 0.72; P = 0.003). CONCLUSIONS: This endovascular study in a porcine model showed that L-lactate and LD activity levels in peritoneal fluid, not in plasma, reflect intestinal ischemia. The study suggests that plasma L-lactate not is a useful early marker in patients with suspicion of intestinal ischemia.

  • 4.
    Almon, Ricardo
    et al.
    Örebro University, Department of Clinical Medicine.
    Alvarez-Leon, Eva E.
    Engfeldt, Peter
    Örebro University, Department of Clinical Medicine.
    Serra-Majem, Lluis
    Magnuson, Anders
    Nilsson, Torbjörn K.
    Associations between lactase persistence and the metabolic syndrome: a Mendelian randomization study in the Canary Islands2009Conference paper (Refereed)
  • 5.
    Almon, Ricardo
    et al.
    Örebro University, Department of Clinical Medicine.
    Alvarez-Leon, Eva E.
    Univ Las Palmas Gran Canaria, Fac Hlth Sci, Dept Clin Sci, Canary Isl, Spain; Hosp Insular Gran Canaria, Canarian Hlth Serv, Serv Prevent Med, Canary Isl, Spain.
    Engfeldt, Peter
    Örebro University, Department of Clinical Medicine.
    Serra-Majem, Lluis
    Univ Las Palmas Gran Canaria, Fac Hlth Sci, Dept Clin Sci, Canary Isl, Spain; Hosp Insular Gran Canaria, Canarian Hlth Serv, Serv Prevent Med, Canary Isl, Spain.
    Magnuson, Anders
    Örebro University hospital, Örebro, Sweden.
    Nilsson, Torbjörn K.
    Örebro University hospital, Örebro, Sweden.
    Associations between lactase persistence and the metabolic syndrome in a cross-sectional study in the Canary Islands2009In: European Journal of Nutrition, ISSN 1436-6207, E-ISSN 1436-6215, Vol. 49, no 3, p. 141-146Article in journal (Refereed)
    Abstract [en]

    Background: The single nucleotide polymorphism (SNP) LCT -13910 C>T, associated with genetically determined phenotypes of lactase persistence (LP) or non-persistence (LNP), was studied in relation to the metabolic syndrome (MS).

    AIim of the study: The aim was to determine if milk intake and MS are associated. We applied Mendelian randomization (MR). The SNP, LCT -13910 C>T, with the genotypes LP (TT/CT) and LNP (CC), was taken as a proxy for milk consumption.

    Methods: A representative sample of adults belonging to the Canary Islands Nutrition Survey (ENCA) in Spain aged 18-75 years (n = 551) was genotyped for the LCT -13910 C>T polymorphism. We used the International Diabetes Federation (IDF) criteria to define MS. RESULTS: 60% of the population was LP and 40% LNP. One hundred seven LP subjects (35.0%) and 53 LNP subjects (25.6%) showed MS (chi (2) = 5.04, p = 0.025). LP subjects showed a significantly higher odds ratio (OR) for MS than LNP subjects computed for the whole population: both the crude OR (1.56; 95% CI 1.06-2.31) and adjusted OR for sex, age, daily energy intake, physical activity and educational level (1.57; 95% CI 1.02-2.43). Adjusted OR for women with LP was 1.93; 95% CI 1.06-3.52.

    Conclusions: The T allele of the SNP might constitute a nutrigenetic factor increasing the susceptibility of LP subjects, especially women, to develop MS in the Canary Islands.

  • 6.
    Almon, Ricardo
    et al.
    Örebro University, Department of Clinical Medicine.
    Alvarez-Leon, Eva E.
    Engfeldt, Peter
    Örebro University, Department of Clinical Medicine.
    Serra-Majem, Lluis
    Nilsson, Torbjörn K.
    Associations between lactase persistence and the metabolic syndrome: a cross-sectional study in the Canary Islands2009Conference paper (Refereed)
  • 7.
    Almon, Ricardo
    et al.
    Örebro University, School of Health and Medical Sciences.
    Engfeldt, Peter
    Örebro University, School of Health and Medical Sciences.
    Tysk, Curt
    Örebro University, School of Health and Medical Sciences.
    Sjöström, Michael
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Prevalence and trends in adult-type hypolactasia in different age cohorts in Central Sweden diagnosed by genotyping for the adult-type hypolactasia-linked LCT -13910C > T mutation2007In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, E-ISSN 1502-7708, Vol. 42, no 2, p. 165-170Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: Adult-type hypolactasia (AtH) can be diagnosed by genotyping in addition to functional tests or intestinal biopsy. The aims of this study were to estimate the prevalence of AtH by genotyping and to investigate whether AtH prevalence has changed in Sweden during the 20th century. MATERIAL AND METHODS: Schoolchildren (n=690) born in 1983 and 1989, and elderly individuals (n=392) born between 1920 and 1932 were genotyped for AtH using Pyrosequencing technology. RESULTS: The overall prevalence of AtH among children was 14.1%. The majority of children (92%, n=635) were Caucasians with genotype prevalences: CC, 61 (10%); CT, 259 (41%); TT, 307 (49%). The frequency of the mutated allele q was 0.300 in this cohort. The prevalence of AtH estimated from the Hardy-Weinberg equilibrium (HWE) (q 2), was 9.0% (95% CI: 6.7-11.2%). Eight percent (n=55) of the children were non-Caucasian; genotype prevalences were CC, 36 (66%); CT, 15 (27%); TT, 4 (7%). The prevalence of AtH in these children estimated from HWE was 62.5% (95% CI: 49.7-75.3%). The elderly subjects were all Caucasians. Their genotype prevalences were: CC, 20 (5%); CT, 166 (42%); TT, 206 (53%); the frequency of the mutated allele q was 0.262 and their AtH prevalence estimated from HWE was 6.8% (95% CI: 4.3-9.2%). CONCLUSIONS: The overall prevalence of AtH in children (14%) was higher than previously thought. Among Caucasians, higher figures were seen in children than in the elderly (9% versus 6.8%). The prevalence thus seems to be increasing and this may be due to the immigration of both non-Caucasian and Caucasian groups with a higher prevalence of AtH.

  • 8.
    Almon, Ricardo
    et al.
    Örebro University, School of Health and Medical Sciences.
    Patterson, Emma
    Unit Prevent Nutr, Dept Biosci & Nutr, Karolinska Inst, Huddinge, Sweden; Sch Biol Sci, Dublin Inst Technol, Dublin, Ireland.
    Nilsson, Torbjörn K.
    Örebro University Hospital, Örebro, Sweden.
    Engfeldt, Peter
    Örebro University, School of Health and Medical Sciences.
    Sjöström, Michael
    Unit Prevent Nutr, Dept Biosci & Nutr, Karolinska Inst, Huddinge, Sweden.
    Body fat and dairy product intake in lactase persistent and non-persistent children and adolescents2010In: Food & Nutrition Research, ISSN 1654-6628, E-ISSN 1654-661X, Vol. 54, article id 5141Article in journal (Refereed)
    Abstract [en]

    Background: Lactase non-persistent (LNP) individuals may be lactose intolerant and therefore on a more restricted diet concerning milk and milk products compared to lactase persistent (LP) individuals. This may have an impact on body fat mass.

    Objective This study examines if LP and LNP children and adolescents, defined by genotyping for the LCT-13910 C > T polymorphism, differ from each other with regard to milk and milk product intake, and measures of body fat mass.

    Design: Children (n=298, mean age 9.6 years) and adolescents (n=386, mean age 15.6 years), belonging to the Swedish part of the European Youth Heart Study, were genotyped for the LCT-13910 C > T polymorphism. Dietary intakes of reduced and full-fat dairy varieties were determined.

    Results: LNP (CC genotype) subjects consumed less milk, soured milk and yoghurt compared to LP (CT/TT genotype) subjects (p<0.001). Subsequent partitioning for age group attenuated this observation (p=0.002 for children and p=0.023 in adolescents). Six subjects were reported by parents to be 'lactose intolerant', none of whom were LNP. LNP children and adolescents consumed significantly less reduced fat milk and milk products than LP children and adolescents (p=0.009 for children and p=0.001 for adolescents).

    Conclusions: We conclude that LP is linked to an overall higher milk and dairy intake, but is not linked to higher body fat mass in children and adolescents.

  • 9. Block, T.
    et al.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Björck, M.
    Acosta, S.
    Diagnostic accuracy of plasma biomarkers for intestinal ischaemia2008In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 68, no 3, p. 242-248Article in journal (Refereed)
    Abstract [en]

    Objective. Intestinal ischaemia is a life‐threatening condition with high mortality, and the lack of accurate and readily available diagnostic methods often results in delay in diagnosis and treatment. The aim of this study was to investigate the accuracy of different plasma biomarkers in diagnosing intestinal ischaemia. Material and methods. Prospective inclusion of patients older than 50 years with acute abdomen admitted to hospital in Karlskrona, Sweden, between 2001 and 2003. Venous blood was sampled prior to any surgery and within 24h from onset of pain. D‐lactate, alpha glutathione S‐transferase, intestinal fatty acid binding protein, creatine kinase B, isoenzymes of lactate dehydrogenase (LD) and alkaline liver phosphatase (ALP) were analysed. D‐dimer was analysed using four different commercially available test kits. Results. In‐hospital mortalities among patients with (n = 10) and without (n = 61) intestinal ischaemia were 40% and 3%, respectively (p = 0.003). D‐dimer was associated with intestinal ischaemia (p = 0.001) independently of which assay was used. No patient presenting with a normal D‐dimer had intestinal ischaemia. D‐dimer >0.9mg/L had a specificity, sensitivity and accuracy of 82%, 60% and 79%, respectively. Total LD, isoenzymes of LD 1–4 and liver isoenzyme of ALP (ALP liver) were significantly higher in patients with intestinal ischaemia, and accuracies for LD 2 (cut‐off 2.3µkat/L) and ALP liver (cut‐off 0.7µkat/L) were 69% and 66%, respectively. Conclusions. D‐dimer may be used as an exclusion test for intestinal ischaemia, but lacks specificity. The other plasma biomarkers studied had insufficient accuracy for this group of patients. Further studies are needed. 

  • 10. Block, Tomas
    et al.
    Isaksson, Helena S.
    Örebro University, School of Health and Medical Sciences.
    Acosta, Stefan
    Björck, Martin
    Brodin, David
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Altered mRNA Expression due to Acute Mesenteric Ischaemia in a Porcine Model2011In: European Journal of Vascular and Endovascular Surgery, ISSN 1078-5884, E-ISSN 1532-2165, Vol. 41, no 2, p. 281-287Article in journal (Refereed)
    Abstract [en]

    Introduction: Messenger RNA (mRNA) changes in the small intestine in response to acute mesenteric ischaemia (AMI) could offer novel diagnostic possibilities, but have not been described. The aim was to characterize the mRNA response to experimental AMI. Materials and methods: Twelve pigs underwent catheterisation of the superior mesenteric artery with injection of polivinylalcohol embolisation particles or sodium chloride. Laparotomy and intestinal tissue sampling were performed. Microarray analysis was performed using the GeneChip (R) whole porcine genome array. Results: Seven down-regulated cellular pathways were associated with protein, lipid and carbohydrate metabolism. Seventeen up-regulated pathways were associated with inflammatory and immunological activity, regulation of extracellular matrix and decreased cellular proliferation. Thrombospondin (THS), monocyte chemoattractant protein 1(MCP-1) and gap junction alpha 1(GJA-1) were consistently up-regulated in all embolised pigs. Genes encoding earlier proposed biomarkers for AMI were up-regulated, such as lactate dehydrogenase and creatine kinase, or down-regulated, such as intestinal fatty acid binding protein and glutathione S-transferase. Conclusion: This study describes the intestinal tissue response on a gene expression level to AMI. THS, MCP-1 and GJA-1 were consistently up-regulated by ischaemia, whereas earlier proposed biomarkers for AMI were not. Gene expression may not be directly linked to the use of the corresponding proteins as potential clinical biomarkers. (C) 2010 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

  • 11.
    Breimer, Lars H.
    et al.
    Departments of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Clinical Medicine, Biomedicine, Örebro University, Örebro, Sweden; Departments of Laboratory Medicine Örebro University Hospital, Örebro, Sweden.
    Has folate a role in the developing nervous system after birth and not just during embryogenesis and gestation?2012In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 72, no 3, p. 185-191Article, review/survey (Refereed)
    Abstract [en]

    It is now 30 years since the first publications stating that supplementation with folate could prevent neural tube defects appeared and 20 years since the definitive data, including prevention of other birth defects. Since then epidemiological studies and animal experiments have identified folate as a molecule at the crossroads of neural development. Fortification of food has greatly reduced the incidence of spina bifida. Much interest has focussed on long-term sequelae in children born to mothers severely deprived of folate (and other nutrients) such as during the Dutch Hunger Winter of 1944 and in poor parts of the world. In addition, deficiency in folate and B12 are increasingly discussed as a possible contributing factor in dementia and congenital orofacial and heart malformations. The year 2011 saw the publication of a study that implicated low folate intake in poorer school performance of adolescents as judged by school marks. This has enormous social implications but needs confirmation from other settings. This review assesses the current state of evidence and sets the data in context of whether folate has a role in the development and plasticity of the nervous system even after birth, with particular emphasis on childhood and adolescence.

  • 12. Börjel, Anna K.
    et al.
    Yngve, Agneta
    Karolinska Inst, Huddinge, Sweden.
    Sjöström, Michael
    Nilsson, Torbjörn K.
    Novel mutations in the 5'-UTR of the FOLR1 gene2006In: Clinical Chemistry and Laboratory Medicine, ISSN 1434-6621, E-ISSN 1437-4331, Vol. 44, no 2, p. 161-167Article in journal (Refereed)
    Abstract [en]

    We have previously reported two novel mutations in the 5'-untranslated region (UTR) of the gene for folate receptor-alpha (FOLR1). In our search for additional mutations, 92 patient samples with elevated levels of homocysteine were screened by single-strand conformation polymorphism (SSCP) between nt -425 and -782, and -712 and -1110. Between nt -425 and -782 we did not find any mutations. Between nt -712 and -1110 there were three novel mutations. One subject had two mutations very close to each other, c.-856C>T and c.-921T>C. Two subjects had a c.-1043G>A mutation. To get an idea of the prevalence of FOLR1 mutations in an unselected population, we also screened 692 healthy school children for mutations. In this cohort, between nt -188 and +272 we discovered one novel mutation, a single nucleotide substitution, c.-18C>T, in addition to five children with the 25-bp deletion mutation previously described by us. Thus, so far we have discovered six novel mutations in the 5'-UTR region of the gene for folate receptor-alpha. We genotyped all 17 subjects with a FOLR1 mutation for the methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism, and developed new single-nucleotide polymorphism (SNP) genotyping protocols for MTHFR 1298A>C and 1793G>A utilising Pyrosequencing technology. None of the 17 subjects had the 677TT genotype, which ruled out this as a cause of elevated homocysteine levels, which was observed in some of the subjects. Further studies of mutations in the 5'-UTR of FOLR1, and in particular of their interplay with folate intake status, are warranted.

  • 13.
    Böttiger, A. K.
    et al.
    Örebro University, School of Health and Medical Sciences.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Pyrosequencing assay for genotyping of the Transcobalamin II 776C>G polymorphism2007In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 67, no 2, p. 247-251Article in journal (Refereed)
    Abstract [en]

    The 776C>G polymorphism of the Transcobalamin II gene is located in a GC-rich region and TaqMan real-time polymerase chain reaction (PCR) does not yield satisfactory genotyping results. We therefore hypothesized that a method based on DNA sequencing would be needed for this single nucleotide polymorphism (SNP) analysis; Pyrosequencing technology was tested for this purpose. A Pyrosequencing protocol was developed, optimized and applied to a sample of 389 Swedish senior citizens. The three genotypes CC, CG, and GG consistently yielded typical programs that were readily distinguishable from each other. The prevalence of the mutated allele in the studied Swedish population was q=0.445. It is concluded that the TC II 776C>G polymorphism can be reliably genotyped by Pyrosequencing technology.

  • 14.
    Böttiger, Anna K.
    et al.
    Örebro University, School of Health and Medical Sciences.
    Hagnelius, Nils-Olof
    Örebro University, School of Health and Medical Sciences.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Mutations in exons 2 and 3 of the FOLR1 gene in demented and non-demented elderly subjects2007In: International Journal of Molecular Medicine, ISSN 1107-3756, E-ISSN 1791-244X, Vol. 20, no 5, p. 653-662Article in journal (Refereed)
    Abstract [en]

    We have previously reported six novel mutations in the 5'-UTR of the gene for folate receptor-alpha (FOLR1). In our search for additional mutations we screened patients, referred for investigation of suspected dementia (DGM subgroup) by SSCP and DNA sequencing from the end of exon 1 to the first bases of intron 3. We found 4 sequence variations, FOLR1 g.1314G>A, g.1816delC, g.1841G>A, and g.1928C>T. Pyrosequencing genotyping assays were developed for all of them, and 389 active seniors (AS subgroup) and the 202 DGM patients were genotyped for these mutations. The frequency q of the mutated allele was, among the AS subjects, 0.068, 0.0026, 0.0026, and 0.024 respectively, and among the DGM subjects, 0.067, 0.0076, 0.0078, and 0.023. The g.1816delC and g.1841G>A mutations thus were more frequent in the DGM than in the AS subgroup, but the difference did not reach statistical significance. The mutated alleles, FOLR1 1816(-) and 1841A, always occurred together in the same subjects, suggestive of a rare double-mutant haplotype. The two common polymorphisms, FOLR1 g. 1314G>A and g.1928C>T seemed not to raise tHcy plasma levels, whereas the double-mutated g.1816(-)-g.1841A haplotype may possibly have a slight tHcy-raising effect. Thus, so far 8 novel rare FOLR1 mutations with a combined prevalence of approximately 1.3% in Whites as well as two common polymorphisms with 5% and 13%, respectively, have been demonstrated. Only a few of the rare mutations may potentially be associated with raised plasma tHcy concentrations. No association with dementia was found.

  • 15.
    Böttiger, Anna K.
    et al.
    Orebro Univ Hosp, Dept Clin Chem, SE-70185 Orebro, Sweden.
    Hurtig-Wennlöf, Anita
    Sjöström, Michael
    Yngve, Agneta
    Karolinska Inst, Dept Biosci & Nutr, SE-14157 Huddinge, Sweden.
    Nilsson, Torbjorn K.
    Association of total plasma homocysteine with methylenetetrahydrofolate reductase genotypes 677C > T, 1298A > C, and 1793G > A and the corresponding haplotypes in Swedish children and adolescents2007In: International Journal of Molecular Medicine, ISSN 1107-3756, E-ISSN 1791-244X, Vol. 19, no 4, p. 659-665Article in journal (Refereed)
    Abstract [en]

    We studied 692 Swedish children and adolescents (aged 9-10 or 15-16 years, respectively), in order to evaluate the effect of the methylenetetrahydrofolate reductase (MTHFR) 677C > T, 1298A > C, and 1793G > A polymorphisms on total plasma homocysteine concentrations (tHcy). Genotyping was performed with Pyrosequencing (TM) technology. The MTHFR 677C > T polymorphism was associated with increased tHcy concentrations in both the children and the adolescents (P < 0.001 for both age groups) in both genders. The effect of MTHFR 1298A > C was studied separately in subjects with the 677CC and 677CT genotypes, and the 1298C allele was found to be associated with higher tHcy levels both when children were stratified according to 677C > T genotypes, and when using haplotype analyses and diplotype reconstructions. The 1793A allele was in complete linkage disequilibrium with the 1298C allele. It was still possible to show that the 1793A allele was associated with lower tHcy levels, statistically significant in the adolescents. In conclusion, a haplotype-based approach was slightly superior in explaining the genetic interaction on tHcy plasma levels in children and adolescents than a simple genotype based approach (R-2 adj 0.44 vs. 0.40). The major genetic impact on tHcy concentrations is attributable to the MTHFR 677C > T polymorphism. The common 1298A > C polymorphism had a minor elevating effect on tHcy, whereas the 1793G > A polymorphism had a lowering effect on tHcy.

  • 16.
    Böttiger, Anna K.
    et al.
    Örebro University, School of Health and Medical Sciences.
    Hurtig-Wennlöf, Anita
    Örebro University, School of Health and Medical Sciences.
    Sjöström, Michael
    Yngve, Agneta
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Association of total plasma homocysteine with methylenetetrahydrofolate reductase genotypes 677C>T, 1298A>C, and 1793G>A and the corresponding haplotypes in Swedish children and adolescents2007In: International Journal of Molecular Medicine, ISSN 1107-3756, E-ISSN 1791-244X, Vol. 19, no 4, p. 659-665Article in journal (Refereed)
    Abstract [en]

    We studied 692 Swedish children and adolescents (aged 9-10 or 15-16 years, respectively), in order to evaluate the effect of the methylenetetrahydrofolate reductase (MTHFR) 677C>T, 1298A>C, and 1793G>A polymorphisms on total plasma homocysteine concentrations (tHcy). Genotyping was performed with Pyrosequencing technology. The MTHFR 677C>T polymorphism was associated with increased tHcy concentrations in both the children and the adolescents (P<0.001 for both age groups) in both genders. The effect of MTHFR 1298A>C was studied separately in subjects with the 677CC and 677CT genotypes, and the 1298C allele was found to be associated with higher tHcy levels both when children were stratified according to 677C>T genotypes, and when using haplotype analyses and diplotype reconstructions. The 1793A allele was in complete linkage disequilibrium with the 1298C allele. It was still possible to show that the 1793A allele was associated with lower tHcy levels, statistically significant in the adolescents. In conclusion, a haplotype-based approach was slightly superior in explaining the genetic interaction on tHcy plasma levels in children and adolescents than a simple genotype based approach (R2 adj 0.44 vs. 0.40). The major genetic impact on tHcy concentrations is attributable to the MTHFR 677C>T polymorphism. The common 1298A>C polymorphism had a minor elevating effect on tHcy, whereas the 1793G>A polymorphism had a lowering effect on tHcy.

  • 17. Edlund, Bror
    et al.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    A proposed stoichiometrical calibration procedure to achieve transferability of D-dimer measurements and to characterize the performance of different methods2006In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 39, no 2, p. 137-142Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: There is little transferability between D-dimer levels obtained by different reagents today. This makes it difficult to compare results from different clinical studies. OBJECTIVES: We give a comprehensive proposal for calibration of D-dimer assays. All crucial steps and underlying assumptions are made explicit. METHODS: The new approach is based on using a set of fibrinolysates of patient samples clotted and treated with tPA to obtain maximal conversion to D-dimers. Their expected maximal D-dimer concentrations are calculated stoichiometrically from their different fibrinogen values and the published molecular masses of fibrinogen and average D-dimer. The characteristics of five latex enhanced D-dimer immunoassays were also tested against early and late fibrin fragments using this procedure. These were produced by prolonged fibrinolysis of a set of patient samples of varying fibrinogen concentrations. RESULTS: These varied typically between methods and lysis times. One of the methods showing the highest yield irrespective of lysis time was used for calibration. A linear standard curve with zero intercept and R2 = 0.95 was obtained. CONCLUSION: Following this procedure will allow better transferability of D-dimer in future clinical trails.

  • 18. Eriksson, Maria
    et al.
    Johnson, Owe
    Boman, Kurt
    Hallmans, Göran
    Hellsten, Gideon
    Nilsson, Torbjörn K
    Örebro University, School of Health and Medical Sciences.
    Söderberg, Stefan
    Improved fibrinolytic activity during exercise may be an effect of the adipocyte-derived hormones leptin and adiponectin2008In: Thrombosis Research, ISSN 0049-3848, E-ISSN 1879-2472, Vol. 122, no 5, p. 701-708Article in journal (Refereed)
    Abstract [en]

    INTRODUCTION: Physical activity is associated with improved fibrinolytic activity and reduced risk for cardiovascular disease. High levels of leptin and low levels of adiponectin, both adipocyte-derived hormones, or adipokines, are related to dysfibrinolysis and risk for cardiovascular disease. In this study, we explored if improved fibrinolytic activity during exercise could be linked to changes in leptin and adiponectin levels.

    MATERIALS AND METHODS: Twenty healthy men (mean age 36 years) participated in a 14-day long skiing expedition in the Swedish mountains. They were randomly assigned to either a 40% or a 30% fat-based diet. Anthropometry, lipids, fibrinolytic activity (PAI-1 activity, tPA activity and mass) and adipokines (leptin and adiponectin) were measured before, during and six weeks after the expedition.

    RESULTS: PAI-1 activity and circulating levels of leptin decreased whereas levels of adiponectin increased during exercise. The fall in PAI-1 activity showed a strong linear association with changes in leptin and adiponectin levels (p = 0.001 and p < 0.001, respectively). Changes in leptin and adiponectin levels were independent of decreasing waist circumference. However, the association between anthropometric measures and adipokines changed considerably during the expedition. Adiponectin was weakly and negatively associated with BMI at baseline. In contrast, there was a strong positive association between adiponectin and BMI after two weeks of exercise, whereas the association between leptin and BMI became less pronounced. In addition, increasing leptin and decreasing adiponectin levels were associated with increasing PAI-1 activity during the six weeks following the expedition. After six weeks of normal activity, fibrinolytic activity and hormone levels returned towards baseline levels.

    CONCLUSION: Heavy exercise induced improved fibrinolytic activity, which was associated independently with changes in circulating levels of the adipocyte-derived hormones leptin and adiponectin. Improved fibrinolytic activity (and reduced risk for cardiovascular disease) related to physical activity could possibly be mediated by leptin and adiponectin. 

  • 19.
    Farkas, Sanja A.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Befkadu, Rahel
    Department of Laboratory Medicine; Örebro University Hospital; Örebro, Sweden.
    Hahn-Strömberg, Victoria
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Nilsson, Torbjörn K.
    Department of Medical Biosciences/Clinical Chemistry, Umeå University, Umeå, Sweden.
    DNA methylation and expression of the folate transporting genes in colorectal cancerManuscript (preprint) (Other academic)
    Abstract [en]

    This study investigated the DNA methylation pattern and protein expression of the FOLR1, PCFT, and RFC1 genes in colorectal cancer (CRC) tissue. Our results showed statistically significant differences in the DNA methylated fraction of all three genes at several gene regions, we identified 3 differentially methylated CpG sites in the FOLR1 gene, 5 CpG sites in the PCFT gene, and 6 CpG sites in the RFC1 gene. We observed a pronounced expression of the FRα and RFC proteins in both the cancer and normal tissues, though the proteins were moderately expressed in cancer compared to the high expression in the paired healthy mucosa. The PCFT protein was undetectable or expressed very low in both tissues. Higher methylated fractions of the CpG sites 3-5 in the RFC1 gene were associated with a lower protein expression. When analyzing the association between DNA methylation and tumor characteristics (differentiation, location, primary tumor stage and lymph node involvement) we detected lower methylated fraction of specific CpG sites in the RFC1 gene in CRC located in the distal colon and rectum compared to the proximal colon. In the FOLR1 gene, we found CpG sites with a lower methylated fraction of colorectal cancers with the primary tumor stage 4 (pT4) compared to the pT2 and pT3 stages. Our results did not show association between the RFC and FRα protein expression and tumor stage, TNM classification or tumor location. In conclusion, these data suggest that there is a possible epigenetic regulation by DNA methylation of the RFC1 gene in the colorectal cancer.

  • 20.
    Farkas, Sanja A.
    et al.
    Department of Laboratory Medicine, Örebro University Hospital, Region Örebro County, Örebro, Sweden.
    Böttiger, Anna K.
    Department of Laboratory Medicine, Örebro University Hospital, Region Örebro County, Örebro, Sweden.
    Isaksson, Helena S.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Örebro University Hospital, Region Örebro County, Örebro, Sweden.
    Finnell, Richard H.
    Department of Nutritional sciences, Dell pediatric Research Institute, University of Texas, Austin, USA.
    Ren, Aiguo
    Institute of Reproductive and Child health, Ministry of health Key Laboratory of Reproductive health, Peking University health science center, Beijing, P.R. China.
    Nilsson, Torbjorn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Örebro University Hospital, Region Örebro County, Örebro, Sweden.
    Epigenetic alterations in folate transport genes in placental tissue from fetuses with neural tube defects and in leukocytes from subjects with hyperhomocysteinemia2013In: Epigenetics, ISSN 1559-2294, E-ISSN 1559-2308, Vol. 8, no 3, p. 303-316Article in journal (Refereed)
    Abstract [en]

    The objectives of this study were to identify tissue-specific differentially methylated regions (T-DMR's) in the folate transport genes in placental tissue compared with leukocytes, and from placental tissues obtained from normal infants or with neural tube defects (NTDs). Using pyrosequencing, we developed methylation assays for the CpG islands (CGIs) and the CGI shore regions of the folate receptor a (FOLR1), proton-coupled folate transporter (PCFT) and reduced folate carrier 1 (RFC1) genes. The T-DMRs differed in location for each gene and the difference in methylation ranged between 2 and 54%. A higher T-DMR methylated fraction was associated with a lower mRNA level of the FOLR1 and RFC1 genes. Methylation fractions differed according to RFC1 80G > A genotype in the NTD cases and in leukocytes from subjects with high total plasma homocysteine (tHcy). There were no differences in methylated fraction of folate transporter genes between NTD cases and controls. We suggest that T-DMRs participate in the regulation of expression of the FOLR1 and RFC1 genes, that the RFC1 80G > A polymorphism exerts a gene-nutrition interaction on DNA methylation in the RFC1 gene, and that this interaction appears to be most prominent in NTD-affected births and in subjects with high tHcy concentrations.

  • 21.
    Farkas, Sanja A.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital.
    Milutin-Gasperov, Nina
    Dept Mol Med, Rudjer Boskovic Inst, Zagreb, Croatia.
    Grce, Magdalena
    Dept Mol Med, Rudjer Boskovic Inst, Zagreb, Croatia.
    Nilsson, Torbjorn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Genome-wide DNA methylation assay reveals novel candidate biomarker genes in cervical cancer2013In: Epigenetics, ISSN 1559-2294, E-ISSN 1559-2308, Vol. 8, no 11, p. 1213-1225Article in journal (Refereed)
    Abstract [en]

    The oncogenic human papilloma viruses (HPVs) are associated with precancerous cervical lesions and development of cervical cancer. The DNA methylation signatures of the host genome in normal, precancerous and cervical cancer tissue may indicate tissue-specific perturbation in carcinogenesis. The aim of this study was to identify new candidate genes that are differentially methylated in squamous cell carcinoma compared with DNA samples from cervical intraepithelial neoplasia grade 3 (CIN3) and normal cervical scrapes. The Illumina Infinium HumanMethylation450 BeadChip method identifies genome-wide DNA methylation changes in CpG islands, CpG shores and shelves. Our findings showed an extensive differential methylation signature in cervical cancer compared with the CIN3 or normal cervical tissues. The identified candidate biomarker genes for cervical cancer represent several types of mechanisms in the cellular machinery that are epigenetically deregulated by hypermethylation, such as membrane receptors, intracellular signaling and gene transcription. The results also confirm extensive hypomethylation of genes in the immune system in cancer tissues. These insights into the functional role of DNA methylome alterations in cervical cancer could be clinically applicable in diagnostics and prognostics, and may guide the development of new epigenetic therapies.

  • 22.
    Farkas, Sanja A.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Department of Laboratory Medicine.
    Vymetalkova, Veronika
    Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic; nstitute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.
    Vodickova, Ludmila
    Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic; nstitute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic; Biomedical Centre, Faculty of Medicine in Pilsen, Charles University, Czech Republic.
    Vodicka, Pavel
    Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Prague, Czech Republic; nstitute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.
    Nilsson, Torbjörn K.
    Department of Medical Biosciences, Clinical Chemistry, Umeå University, Umeå, Sweden.
    DNA methylation changes in genes frequently mutated in sporadic colorectal cancer and in the DNA repair and Wnt/beta-catenin signaling pathway genes2014In: Epigenomics, ISSN 1750-1911, Vol. 6, no 2, p. 179-191Article in journal (Refereed)
    Abstract [en]

    Aim: The onset and progression of colorectal cancer (CRC) involves a cascade of genetic and/or epigenetic events. The aim of the present study was to address the DNA methylation status of genes relevant in colorectal carcinogenesis and its progression, such as genes frequently mutated in CRC, genes involved in the DNA repair and Wnt signaling pathway.

    Material & methods: We analyzed methylation status in totally 160 genes in 12 paired colorectal tumors and adjacent healthy mucosal tissues using the Illumina Infinium Human Methylation 450 BeadChip.

    Results: We found significantly aberrant methylation in 23 genes (NEIL1, NEIL3, DCLRE1C, NHEJ1, GTF2H5, CCNH, CTNNB1, DKK2, DKK3, FZD5 LRP5, TLE3, WNT2, WNT3A, WNT6, TCF7L1, CASP8, EDNRB1, GPC6, KIAA1804, MYO1B, SMAD2 and TTN). External validation by mRNA expression showed a good agreement between hypermethylation in cancer and down-regulated mRNA expression of the genes EDNRB1, GPC6 and SMAD2, and between hypomethylation and up-regulated mRNA expression of the CASP8 and DCLRE1C genes.

    Conclusion: Aberrant methylation of the DCLRE1C and GPC6 genes are presented here for the first time and are therefore of special interest for further validation as novel candidate biomarker genes in CRC, and merit further validation with specific assays.

  • 23.
    Gustafsson, Dan
    et al.
    Departments of Pediatrics, Örebro University Hospital, Örebro, Sweden.
    Breimer, Lars H.
    Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden;.
    Isaksson, Helena S.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden; Department of Clinical Medicine and Biomedicine, Örebro University, Örebro, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden; Department of Clinical Medicine and Biomedicine, Örebro University, Örebro, Sweden.
    Tissue zinc levels in a child with hypercalprotectinaemia and hyperzincaemia: a case report and a review of the literature2012In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 72, no 1, p. 34-38Article, review/survey (Refereed)
    Abstract [en]

    Background: A girl suffering from a rare syndrome of unknown aetiology, termed hypercalprotectinaemia, was evaluated for tissue zinc status, because calprotectin is a protein which chelates Zn at multiple binding-sites, which might have affected the distribution of Zn in her body.

    Methods: Measurement of serum, urine, hair and nail zinc (Zn) concentration, complemented with measurement of total Zn in ultrafiltrates of plasma.

    Results: Her serum Zn concentration was 105-133 mu mol/L. Zn levels in her hair (102 mu g/g), nail (90 mu g/g) and urine (3-12 mu mol/L; 20-80 mu g/dL) were all at the lower end of the reference intervals described in the sparse literature. Zn concentrations in ultrafiltrates of plasma were below the detection limit (<100 nmol/L). Thus, the elevated serum Zn did not translate into a similarly increased level of Zn in any of the tissues tested, nor in free Zn concentrations. Instead it appeared to be a result of Zn being chelated to binder proteins, most probably calprotectin.

    Conclusion: Her grossly elevated serum calprotectin concentration is probably able to raise circulating total Zn concentrations without raising ionized concentrations, but this Zn remains confined to the circulating blood as well as to excreted body fluids, particularly faeces.

  • 24.
    Hagnelius, Nils-Olof
    et al.
    Örebro University, School of Health and Medical Sciences.
    Boman, Kurt
    Umeå universitet.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Fibrinolysis and von Willebrand factor in Alzheimer's disease and vascular dementia: a case-referent studyManuscript (preprint) (Other academic)
    Abstract [en]

    Introduction: The importance of vascular risk factors for Alzheimer’s disease (AD) is not settled. Our aim was to compare patients with AD or vascular dementia (VaD) with non-demented subjects with regard to endothelial derived fibrinolytic and hemostatic factors.

    Materials and methods: In a cross-sectional mono-center case-referent study in Örebro, Sweden, we consecutively included 95 patients with AD and 55 with VaD and 154 non-demented active seniors (AS). Plasma biomarkers including the endothelial derived fibrinolytic factors: mass concentrations of tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), tPA/PAI-1 complex and von Willebrand factor (vWF), as well as clinical data were analyzed.

    Results: None of the endothelial derived fibrinolytic markers or vWF differed between AD vs. VaD. In comparison with the AS group, tPA was higher in AD (p=0.001) and VaD (p=0.023) but its inhibitor, PAI-1 mass concentration did not differ significantly; tPA/PAI-1 complex was higher in both VaD (p=0.038) and AD (p=0.005). vWF concentration was lower in the AS group (p<0.001) than in both dementia groups.

    Conclusion: Thus, endothelial derived fibrinolytic factors, tPA/PAI-1 complex and vWF, discriminated between the reference group of non-demented elderly and the AD and VaD groups, but not between AD and VaD. This suggests similar disturbances for endothelial derived fibrinolytic and hemostatic factors among AD and VaD patients and may reflect shared vascular pathophysiological mechanisms in the dementias.

  • 25.
    Hagnelius, Nils-Olof
    et al.
    Örebro University, School of Health and Medical Sciences. Dept of Geriatrics, Örebro University Hospital, Örebro, Sweden.
    Boman, Kurt
    Skellefteå Cty Hosp, Dept Med, Skellefteå, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences. Dept of Laboratory Medicine, Div of Clinical Chemistry, Örebro University Hospital, Örebro, Sweden.
    Fibrinolysis and von Willebrand factor in Alzheimer's disease and vascular dementia: a case-referent study2010In: Thrombosis Research, ISSN 0049-3848, E-ISSN 1879-2472, Vol. 126, no 1, p. 35-38Article in journal (Refereed)
  • 26. Hagnelius, Nils-Olof
    et al.
    Wahlund, Lars-Olof
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    CSF/serum folate gradient: physiology and determinants with special reference to dementia2008In: Dementia and Geriatric Cognitive Disorders, ISSN 1420-8008, E-ISSN 1421-9824, Vol. 25, no 6, p. 516-523Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Folate depletion has been implicated as a risk factor for neurodegenerative disorders. We hypothesized that transport of folate to the cerebrospinal fluid (CSF) compartment could be involved in the pathophysiology of these disorders.

    METHODS: The CSF/serum folate gradient (R(CSF/S)) was studied in 205 subjects with suspected cognitive disorder. Its relation to clinical and biochemical indices, including the integrity of the blood-CSF barrier, were characterized.

    RESULTS: In subjects who were diagnosed as nondemented (ND) the mean R(CSF/S )+/- SD was 2.46 +/- 0.62 versus 2.09 +/- 0.67 (p = 0.008) in the dementia subgroup with a vascular component (VaD + mixed). The ND subgroup had higher CSF folate (p = 0.001) and lower serum homocysteine values (p = 0.001) than the VaD + mixed subgroup. The folate gradient R(CSF/S) was negatively correlated with serum folate (p < 0.001, R(2) = 0.518) and to the albumin ratio, a blood-CSF barrier biomarker (beta = -0.235). The Alzheimer patients had R(CSF/S) and albumin ratios similar to the ND subjects.

    CONCLUSION: The R(CSF/S) was significantly lower in the VaD + mixed dementia subgroup, suggestive of a defect in the transport of folate over the choroid plexus that seems to be characteristic of, and limited to, the VaD + mixed dementia subgroup.

  • 27.
    Hagnelius, Nils-Olof
    et al.
    Örebro University, School of Health and Medical Sciences.
    Wahlund, Lars-Olof
    Karolinska Institutet, Neurotec.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    High homocysteine and methylmalonate among demented and non-demented elderly receiving vitamin-B12 prescription and home help serviceManuscript (preprint) (Other academic)
    Abstract [en]

    Background & Aims: Total homocysteine (tHcy) has been suggested as a dementia risk factor. Our aim was to investigate potential differences in tHcy and its determinants (mainly Serum-B12 and Serum-folate) in relation dementia. We examined the effect of vitamin-B12 prescription, whether a family history of dementia, or the need for home help service might have influence on tHcy.

    Methods: A cross sectional monocenter study comprising 926 consecutive subjects attending our Memory Care Unit.

    Results: Demented subjects being prescribed vitamin-B12 had higher Serum-B12 (p =0.025) but also higher tHcy (p =<0.001) and S-methylmalonate (p =0.032), and lower Serum-folate (p<0.001) than those who did not receive B12 prescriptions. tHcy levels were higher in subjects in need of home help service (non-dementia: p= 0.007), this group also had lower S-albumin (dementia: p<0.001; non-dementia: p=0.004). In multivariate logistic regression analysis with diagnosis of dementia as outcome, both vitamin-B12 prescriptions, family history of dementia, and existent home help service, predicted dementia (p=0.037; 0.044; 0.002 respectively).

    Conclusion: Elderly subjects on vitamin-B12 prescription appear to have unmet needs of nutritional support, causing elevated homocysteine levels. The home help service should pay a closer attention to nutritional aspects and drug compliance among geriatric patients.

  • 28.
    Hagnelius, Nils-Olof
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Geriatric Medicine, Örebro University Hospital, Örebro, Sweden.
    Wahlund, Lars-Olof
    Department of Neurobiology, Care Sciences and Society, Section of Clinical Geriatrics, Karolinska Institutet, Stockholm.
    Schneede, Jörn
    Department of Pharmacology and Clinical Neuroscience, Division of Clinical Pharmacology, University Hospital of Northern Sweden, Umeå, Sweden.
    Nilsson, Torbjörn K.
    Department of Laboratory Medicine, Division of Clinical Chemistry, Örebro University Hospital, Örebro.
    Blood concentrations of homocysteine and methylmalonic acid among demented and non-demented Swedish elderly with and without home care services and vitamin B(12) prescriptions2012In: Dementia and Geriatric Cognitive Disorders, ISSN 1420-8008, E-ISSN 1421-9824, Vol. 2, no 1, p. 387-399Article in journal (Refereed)
    Abstract [en]

    Background and Aims: Total plasma homocysteine (tHcy) has been suggested as a risk factor of dementia. Our aim was to investigate potential differences in tHcy status in relation to the prescription of vitamin B(12) and dementia diagnosis. We examined whether vitamin B(12) prescriptions, a family history of dementia, or the need for home care service might be associated with tHcy values.

    Methods: A cross-sectional monocenter study comprising 926 consecutive subjects attending our Memory Care Unit was conducted.

    Results: Demented subjects being prescribed vitamin B(12) had higher serum vitamin B(12) (p = 0.025) but also higher tHcy (p < 0.001) and serum methylmalonate (p = 0.032), and lower serum folate (p < 0.001) than those who did not receive vitamin B(12) prescriptions. tHcy levels were significantly higher in non-demented subjects receiving home care service (p = 0.007). This group also had lower serum albumin (dementia: p < 0.001; non-dementia: p = 0.004). There was no difference in renal function (estimated glomerular filtration rate) in demented or non-demented subjects with or without vitamin B(12) prescriptions (dementia with/without vitamin B(12) prescription: p = 0.561; non-dementia with/without vitamin B(12) prescription: p = 0.710).

    Conclusion: Despite vitamin B(12) prescriptions, demented subjects had higher tHcy and methylmalonate values. The elevated metabolite values could not be explained by differences in renal function. Thus, elderly subjects on vitamin B(12) prescription appear to have unmet nutritional needs.

  • 29.
    Hernestal-Boman, Jenny
    et al.
    Dept Publ Hlth & Clin Med, Umeå Univ, Umeå, Sweden.
    Jansson, Jan-Hakan
    Dept Publ Hlth & Clin Med, Umeå Univ, Umeå, Sweden; Dept Med & Geriatr, Skellefteå Cty Hosp, Skellefteå, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences. Örebro University Hospital, Örebro, Sweden.
    Eliasson, Mats
    Dept Publ Hlth & Clin Med, Umeå Univ, Umeå, Sweden; Sunderby Hosp, Dept Med, Luleå, Sweden.
    Johansson, Lars
    Dept Publ Hlth & Clin Med, Umeå Univ, Umeå, Sweden; Dept Med & Geriatr, Skellefteå Cty Hosp, Skellefteå, Sweden.
    Long-term stability of fibrinolytic factors stored at-80 degrees C2010In: Thrombosis Research, ISSN 0049-3848, E-ISSN 1879-2472, Vol. 125, no 5, p. 451-456Article in journal (Refereed)
    Abstract [en]

    Introduction: Blood samples in epidemiological studies are often stored for several years and analysed at different occasions. The reagent kits are continually modified for better precision and accuracy. Our hypothesis was that epidemiological studies are affected by long-term storage and/or modifications of reagent kits. Materials and Methods: Plasma samples stored at -80 degrees C from two populations were used: A case-referent study with samples collected from 1985 to 2000 and analysed 2005 (n=1598) were used to study influence of long-term storage. A cross-sectional study analysed 1990 (n=1558) and re-analysed 2001 (n=78) and 2005 (n=828) was used to study influence of reagent kit modifications. Fibrinolytic analyses included immunoassays of tPA, PAI-1 and tPA-PAI-1 complex and chromogenic substrate assays of the activities of tPA and PAI-1. Results: Long-term storage for a median time of 11.6 years (range 5 to 20) showed an effect of time on tPA antigen R-2=0.01, PAI-1 antigen R-2=0.01 and tPA-PAI-1 complex R-2=0.02. Modifications in reagent kits affected the levels of fibrinolytic factors; for tPA antigen the slope coefficients were between 0.72 and 0.95 (R-2 0.47-0.75), whereas tPA activity showed an agreement with slope coefficients 1.06 to 1.09 (R-2 0.67-0.93). Conclusions: This study showed that long-term storage affects fibrinolytic variables to a negligible extent, but modifications in reagent kits introduced an element of bias. We conclude that analysis of samples on a single occasion is preferable to multiple occasions, as storage has negligible effect. (C) 2009 Elsevier Ltd. All rights reserved.

  • 30.
    Hurtig-Wennlöf, Anita
    et al.
    Örebro University, Department of Clinical Medicine.
    Yngve, Agneta
    Nilsson, Torbjörn K.
    Örebro University, Department of Clinical Medicine.
    Sjöström, Michael
    Serum lipids, glucose and insulin levels in healthy schoolchildren aged 9 and 15 years from Central Sweden: reference values in relation to biological, social and lifestyle factors2005In: Scandinavian Journal of Clinical and Laboratory Investigation, ISSN 0036-5513, E-ISSN 1502-7686, Vol. 65, no 1, p. 65-76Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    There is a shortage of reference values for cardiovascular risk factors such as serum lipids, glucose and insulin related to biological, social and lifestyle factors for Swedish children and adolescents. Such values are needed for planning and evaluation of public health activities, and for clinical use.

    DESIGN AND METHODS:

    Data for this cross-sectional, school-based study were collected during a school year (September to May). A random sample of 1137 girls and boys aged 9 and 15 years from two locations in central Sweden participated in the study, and blood samples were taken from 969 of them.

    METHODS:

    Fasting serum blood samples were analysed for triglycerides, total cholesterol, high-density lipoprotein cholesterol, glucose and insulin. Physical examination included measurement of height, weight and pubertal status. Questionnaires provided family background data. Total physical activity was measured by accelerometer registration.

    RESULTS:

    Serum levels differed significantly between age and gender groups and were correlated to pubertal status. Neither genetic nor socio-economic background nor smoking status influenced the serum levels. Insulin levels were elevated in subjects with a body mass index in the highest decentile, compared with the levels in the rest of the subjects. The insulin levels were inversely associated with total physical activity, and physical activity varied with season.

    CONCLUSIONS:

    Pubertal status (biological age) should to be considered in the interpretation of serum values in schoolchildren rather than chronological age. The interpretation of insulin values should include both body mass index and physical activity level, and perhaps also season. Previously described regional differences in serum lipid levels in Swedish adults seem to be present also in children.

  • 31.
    Isaksson, Helena S.
    et al.
    Örebro University, School of Medical Sciences. Department of Laboratory Medicine, Örebro University Hospital, Faculty of Medicine and Health, Örebro University, Sweden.
    Farkas, Sanja A.
    Örebro University, School of Health Sciences. Örebro University Hospital. Department of Laboratory Medicine.
    Müller, Patrick
    Affymetrix core facility at Novum, BEA, Karolinska Institute, Huddinge, Sweden.
    Gustafsson, Dan
    Department of Pediatrics, Örebro University Hospital, Örebro, Sweden Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Nilsson, Torbjörn, K.
    Department of Medical Biosciences, Clinical Chemistry, Umeå University, Umeå, Sweden.
    Whole genome microarray expression analysis in blood leucocytes identifies pathways linked to signs and symptoms of a patient with hypercalprotectinaemia and hyperzincaemia2018In: Clinical and Experimental Immunology, ISSN 0009-9104, E-ISSN 1365-2249, Vol. 191, no 2, p. 240-251Article in journal (Refereed)
    Abstract [en]

    A child, 2 years with the "hypercalprotectinemia with hyperzincemia" clinical syndrome presented with atypical symptoms and signs, notably persistent fever of around 38°C, thrombocythaemia of >700 x 10(9) /L, and a predominance of persistent intestinal symptoms. In an effort to find a cure by identifying the dysregulated pathways we analyzed whole-genome mRNA expression by the Affymetrix HG U133 PLUS 2.0 array on three occasions 3 to 5 months apart. Major upregulation was demonstrated for the JAK/STAT pathway including in particular CD177, S100A8, S100A9, and S100A12, accounting for the thrombocytosis; a large number of interleukins, their receptors, and activators, accounting for the febrile apathic state; and the HMBG1 gene, possibly accounting for part of the intestinal symptoms. These results show that gene expression array technology may assist the clinician in the diagnostic workup of individual patients with suspected syndromal states of unknown origin, and the expression data can guide the selection of optimal treatment directed at the identified target pathways.

  • 32.
    Isaksson, Helena S.
    et al.
    Örebro University, Department of Clinical Medicine.
    Nilsson, Torbjörn K.
    Örebro University, Department of Clinical Medicine.
    Preanalytical aspects of quantitative TaqMan real-time RT-PCR: applications for TF and VEGF mRNA quantification2006In: Clinical Biochemistry, ISSN 0009-9120, E-ISSN 1873-2933, Vol. 39, no 4, p. 373-377Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: The present paper focuses on preanalytical aspects of tissue factor (TF) and vascular endothelial growth factor (VEGF) mRNA quantification: the choice of blood collection tubes and defining the time frame allowed before processing the sample. DESIGN AND METHODS: Blood was collected from healthy volunteers in K(3) EDTA tubes, CPT, endotoxin-free EndoTube tubes and in PAXgene tubes. Total RNA concentration was determined by absorbance readings at 260 nm with a GeneQuantII UV spectrophotometer. RNA quantity and quality were also determined by the Lab on a Chip technique (Agilent 2100 Bioanalyzer). Real-time RT-PCR assays were performed by the TaqMan technology. RESULTS: The more expensive PAXgene and CPT tubes and the Endo tubes did not give superior results from those obtained in inexpensive routine K(3) EDTA tubes. The PAXgene tubes preserved high molecular mass rRNA better than the other tubes. CONCLUSION: Both the PAXgene system and routine EDTA tubes are suitable for clinical purposes aimed at quantitation of mRNA for TF and VEGF. PAXgene yielded rRNA that was less degraded but had lower mRNA per microg extracted RNA. A time frame up to 24 h until sample processing is acceptable for TF and VEGF mRNA.

  • 33.
    Isaksson, Helena S.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Departments of Laboratory Medicine, Section for Clinical Chemistry, Örebro University Hospital, Örebro, Sweden.
    Sorbe, Bengt
    Departments of Gynecological Oncology, Örebro University Hospital, Örebro, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Departments of Laboratory Medicine, Section for Clinical Chemistry, Örebro University Hospital, Örebro, Sweden.
    Whole blood RNA expression profiles in ovarian cancer patients with or without residual tumors after primary cytoreductive surgery2012In: Oncology Reports, ISSN 1021-335X, E-ISSN 1791-2431, Vol. 27, no 5, p. 1331-1335Article in journal (Refereed)
    Abstract [en]

    Significant improvements in the treatment results of ovarian cancer have been achieved during the last decades, but further improvements require additional methods identifying signs of the disease and its biological behavior, preferably by a simple blood test. We hypothesized that peripheral blood leukocytes may express genes that carry such clinical information. Therefore, we studied the relative gene expressions of 168 cancer- and metastasis-specific genes in blood samples from ovarian cancer patients with different prognoses after primary cytoreductive surgery. Total RNA was extracted from whole blood and the relative gene expression profile of 168 genes were analyzed using real-time qPCR assays. Two groups of patients were analyzed; one group with residual tumor mass after primary surgery, and one group where the tumor was macroscopically radically resected, resulting in no visible tumor mass left behind. The group with the remaining tumor mass after surgery showed significantly different gene expression profiles compared to the group with no remaining tumor mass. Differences were noted for the metastasis associated 1 family, member 2 gene (MTA2), the TNF, alpha-catenin, interleukin 1 beta, the KiSS-1 metastasis suppressor and the matrix metalloproteinase 10 genes. All genes were downregulated with a fold-change between 1.15 to 1.57; there were no upregulated genes. Thus, a signature of genes involved in metastasis, invasion and inflammation was found to be significantly downregulated in native unstimulated blood leukocytes from ovarian cancer patients with a poor prognosis. Preoperatively it may serve as a guide to the biology of the tumor and postoperatively in the optimization of adjuvant treatment of ovarian cancer patients.

  • 34.
    Isaksson, Helena S.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Sorbe, Bengt
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Department of Oncology.
    Nilsson, Torbjörn K.
    Department of Medical Biosciences/Clinical Chemistry, Umeå University, Umeå, Sweden.
    Whole genome expression profiling of blood cells in ovarian cancer patients: prognostic impact of the CYP1B1, MTSS1, NCALD, and NOP14 genes2014In: OncoTarget, ISSN 1949-2553, E-ISSN 1949-2553, Vol. 5, no 12, p. 4040-4049Article in journal (Refereed)
    Abstract [en]

    Ovarian cancer patients with different tumor stages and cell differentiation might be distinguished from each other by gene expression profiles in whole blood cell mRNA by the Affymetrix Human Gene 1.0 ST Array. We also examined if there is any association with other clinical variables, response to therapy, and residual tumor burden after surgery. Patients were divided into two groups, one with poor prognosis, advanced stage and poorly differentiated tumors (n = 22), and one group with good prognosis, early stage and well-to medium differentiated tumors (n = 11). Six genes were found to be differentially expressed: the PDIA3, LYAR, NOP14, NCALD and MTSS1 genes were down-regulated and the CYP1B1 gene expression was up-regulated in the poor prognosis group, all with p value <0.05, adjusted for mass comparison. In survival analyses, CYP1B1, MTSS1, NCALD and NOP14 remained significantly different (p<0.05). Patient groups did not differ in any transcript related to acute phase or immune responses. This minimal gene expression signature of prognostic ovarian cancer-related genes opens up an avenue for more practicable monitoring of ovarian cancer patients by simple peripheral blood tests, which may evolve into a tool to guide selection of curative and postoperative supportive therapies.

  • 35. Labayen, Idoia
    et al.
    Ortega, Francisco B.
    Sjöström, Michael
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Olsson, Lovisa A.
    Örebro University, School of Health and Medical Sciences.
    Ruiz, Jonatan R.
    Association of common variants of UCP2 gene with low-grade inflammation in Swedish children and adolescents: the European Youth Heart Study2009In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 66, no 3, p. 350-354Article in journal (Refereed)
    Abstract [en]

    We examined the associations of two functional variants 866G>A and DEL/INS polymorphisms of UCP2 gene with low-grade inflammatory proteins (C-reactive protein, fibrinogen, complement C3 [C3], and complement C4 [C4]) in 131 children (52.7% boys, aged 9.5 +/- 0.4 y) and 118 adolescents (44.1% males, aged 15.5 +/- 0.4 y) selected from the European Youth Heart Study. Differences in inflammatory markers among the genotype variants of the two UCP2 gene polymorphisms were analyzed after adjusting for sex, age, pubertal stage, fitness, and fatness. The results showed that fibrinogen, C3, and C4 were higher in GG carriers than in subjects carrying the A allele of the 866G>A polymorphism of the UCP2 gene (UCP2 -866G>A) polymorphism (all p < 0.05). The DEL/DEL genotype of 45nt deletion/insertion variant polymorphism of the UCP2 gene (UCP2 DEL/INS) was associated with higher C3 (p < 0.05) than DEL/INS and INS/INS genotypes. This study provides evidence of a role of UCP2 -866G>A in modifying low-grade inflammatory state in apparently healthy children and adolescents. Given the implication of complement factors on atherosclerosis process, these results contribute to explain the reduced cardiovascular risk associated with the A allele of the UCP2 -866G>A polymorphism.

  • 36. Lind, Marcus
    et al.
    Boman, Kurt
    Johansson, Lars
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Öhlin, Ann-Kristin
    Slunga Birgander, Lisbeth
    Jansson, Jan-Håkan
    Thrombomodulin as a marker for bleeding complications during warfarin treatment2009In: Archives of Internal Medicine, ISSN 0003-9926, E-ISSN 1538-3679, Vol. 169, no 13, p. 1210-1215Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The major adverse effect of warfarin treatment is hemorrhage. Several risk factors for bleeding complications are also risk factors for thromboembolic events, making the clinical decision to initiate or withhold anticoagulant treatment difficult. Specific markers that solely identify patients at high risk of bleeding would have great clinical impact. This study aimed to test if thrombomodulin (TM) concentrations were associated with bleeding complications, cardiovascular events, or mortality in long-term anticoagulant-treated patients. METHODS: In a longitudinal cohort study we followed up 719 patients receiving warfarin treatment for a mean duration of 4.2 years. All bleeding complications causing hospitalization were registered and classified. Soluble TM antigen (sTM) concentration in plasma was measured with an enzyme-linked immunosorbent assay method. RESULTS: During the follow-up time, 113 clinically relevant bleeding events and 73 major bleeding events occurred. Increased concentration of sTM was associated with both clinically relevant bleeding and major bleeding events after adjustment for age. In the multivariable models, hazard ratios for the highest tertiles compared with the lowest were 2.29 (95% confidence interval, 1.35-3.89) and 2.33 (95% confidence interval, 1.21-4.48), respectively. No association between sTM concentration and nonfatal ischemic cardiovascular events or all-cause mortality was found. CONCLUSIONS: Increased levels of sTM are associated with bleeding complications during warfarin treatment but not with cardiovascular events or all-cause mortality. Soluble TM antigen concentration has potential as a new specific marker to identify patients at high risk of bleeding during warfarin treatment.

  • 37. Lindahl, Bernt
    et al.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Borch-Johnsen, Knut
    Røder, Michael E.
    Söderberg, Stefan
    Widman, Lars
    Johnson, Owe
    Hallmans, Göran
    Jansson, Jan-Håkan
    A randomized lifestyle intervention with 5-year follow-up in subjects with impaired glucose tolerance: pronounced short-term impact but long-term adherence problems2009In: Scandinavian Journal of Public Health, ISSN 1403-4948, E-ISSN 1651-1905, Vol. 37, no 4, p. 434-442Article in journal (Refereed)
    Abstract [en]

    AIMS: To compare data on cardiovascular risk factor changes in lipids, insulin, proinsulin, fibrinolysis, leptin and C-reactive protein, and on diabetes incidence, in relation to changes in lifestyle. METHODS: The study was a randomized lifestyle intervention trial conducted in northern Sweden between 1995 and 2000, in 168 individuals with impaired glucose tolerance (IGT) and body mass index above 27 at start. The intensive intervention group (n = 83) was subjected to a 1-month residential lifestyle programme. The usual care group (n = 85) participated in a health examination ending with a single counselling session. Follow-up was conducted at 1, 3 and 5 years. RESULTS: At 1-year follow-up, an extensive cardio-metabolic risk factor reduction was demonstrated in the intensive intervention group, along with a 70% decrease of progress to type 2 diabetes. At 5-year follow-up, most of these beneficial effects had disappeared. Reported physical activity and fibre intake as well as high-density lipoprotein cholesterol were still increased, and fasting insulin and proinsulin were lower. CONCLUSIONS: The intervention affected several important cardio-metabolic risk variables beneficially, and reduced the risk for type 2 diabetes, but the effects persisted only as long as the new lifestyle was maintained. Increased physical activity seemed to be the behaviour that was most easy to preserve.

  • 38.
    Lindqvist, Breezy Malakkaran
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Farkas, Sanja A.
    Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden.
    Wingren, Sten
    Örebro University, School of Medicine, Örebro University, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden.
    DNA methylation pattern of the SLC25A43 gene in breast cancer2012In: Epigenetics, ISSN 1559-2294, E-ISSN 1559-2308, Vol. 7, no 3, p. 300-306Article in journal (Refereed)
    Abstract [en]

    Solute carrier family 25A member 43 (SLC25A43) gene is a putative tumor suppressor gene that undergoes loss of heterozygosity (LOH) in human epidermal growth factor receptor 2 (HER2) positive breast cancer. Also, knockdown of SLC25A43 in cell lines influences cell turnover and metabolism. Absence of mutations in this gene in breast cancers prompted us to study methylation as an alternate mechanism for gene inactivation of this X encoded gene. Quantification of CpG site methylation using pyrosequencing was performed upstream of the SLC25A43 gene and at its 5' end in a cohort of breast tumor tissues (n = 80, HER2 positive or negative) with different SLC25A43 gene deletion status. Compared with control tissue, cancer tissues had lower levels of methylation at the 5' and 3' shores of the gene. Cancer tissues with no deletion in the SLC25A43 gene (Del(-)) had higher methylation in the CpG island (CGI) of the gene than cancers carrying the deletion (Del(+)). Methylation in the CGI of the SLC25A43 gene was negatively correlated with age at diagnosis. In HER2 positive breast cancer, ER negativity and lymph node positivity was associated with higher methylation in the CGI and in the adjacent shores of this gene. Our results suggest that methylation in the CGI of the SLC25A43 gene could be an alternate mechanism of gene silencing in the absence of LOH. Also, associations between site-specific methylation and clinicopathological parameters suggest that epigenetic changes in SLC25A43 gene could be of importance in breast carcinogenesis.

  • 39.
    Lindqvist, Breezy Malakkaran
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Wingren, Sten
    Örebro University, School of Medicine, Örebro University, Sweden.
    Motlagh, Parviz B.
    Department of Medical Biosciences/Clinical Chemistry, Umeå University, Umeå, Sweden.
    Nilsson, Torbjorn K.
    Department of Medical Biosciences/Clinical Chemistry, Umeå University, Umeå, Sweden.
    Whole genome DNA methylation signature of HER2-positive breast cancer2014In: Epigenetics, ISSN 1559-2294, E-ISSN 1559-2308, Vol. 9, no 8, p. 1149-1162Article in journal (Refereed)
    Abstract [en]

    In order to obtain a comprehensive DNA methylation signature of HER2-positive breast cancer (HER2+ breast cancer), we performed a genome-wide methylation analysis on 17 HER2+ breast cancer and compared with ten normal breast tissue samples using the Illumina Infinium HumanMethylation450 BeadChip (450K). In HER2+ breast cancer, we found altered DNA methylation in genes involved in multicellular development, differentiation and transcription. Within these genes, we observed an overrepresentation of homeobox family genes, including several genes that have not been previously reported in relation to cancer (DBX1, NKX2-6, SIX6). Other affected genes included several belonging to the PI3K and Wnt signaling pathways. Notably, HER2, AKT3, HK1, and PFKP, genes for which altered methylation has not been previously reported, were also identified in this analysis. In total, we report 69 candidate biomarker genes with maximum differential methylation in HER2+ breast cancer. External validation of gene expression in a selected group of these genes (n = 13) revealed lowered mean gene expression in HER2+ breast cancer. We analyzed DNA methylation in six top candidate genes (AKR1B1, INA, FOXC2, NEUROD1, CDKL2, IRF4) using EpiTect Methyl II Custom PCR Array and confirmed the 450K array findings. Future clinical studies focusing on these genes, as well as on homeobox-containing genes and HER2, AKT3, HK1, and PFKP, are warranted which could provide further insights into the biology of HER2+ breast cancer.

  • 40.
    Lindqvist, Breezy Malakkaran
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Wingren, Sten
    Örebro University, School of Medicine, Örebro University, Sweden.
    Nilsson, Torbjörn
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Whole genome DNA methylation signature of HER2-positive breast cancerManuscript (preprint) (Other academic)
    Abstract [en]

    With the aim of obtaining a more comprehensive epigenetic signature in HER2-positive breast cancer (HER2+ breast cancer), we performed a genome-wide methylation analysis on 17 HER2+ breast cancer and compared to 10 normal breast tissue samples using the Illumina Infinium HumanMethylation450 BeadChip that interrogates >485,000 CpG loci per sample. Our findings show that altered DNA methylation, more specifically hypermethylation occur at CpG islands in HER2+ breast cancer affecting genes involved in multicellular development, differentiation and transcription, and was overrepresented by the homeobox family of genes, including those which have not been previously reported in relation to cancer (DBX1, NKX2- 6, SIX6). Alteration in methylation was also found to affect genes of the PI3K and the Wnt signalling pathways in HER2+ breast cancer. Notably among them are HER2, AKT3, HK1 and PFKP, in which altered methylation has not been previously reported. We have identified 73 candidate biomarker genes in HER2+ breast cancer and external validation of gene expression in a selected group of these genes (n=13) revealed lowered mean gene expression in HER2+ breast cancer. Future clinical studies focusing on these candidate biomarker genes as well as homeobox-containing genes and HER2, AKT3, HK1 and PFKP are warranted which could provide further insights to the biology of HER2+ breast cancer.

  • 41. Löf-Ohlin, Zarah M.
    et al.
    Hagnelius, Nils-Olof
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Relative telomere length in patients with late-onset Alzheimer's dementia or vascular dementia2008In: NeuroReport, ISSN 0959-4965, E-ISSN 1473-558X, Vol. 19, no 12, p. 1199-1202Article in journal (Refereed)
    Abstract [en]

    Telomeres generally shorten with age. An accelerated shortening of the telomeres has been linked to several age-related disorders. We hypothesized that the relative length of telomeres could discriminate between patients with late-onset Alzheimer's disease (AD) and vascular dementia (VaD). A quantitative real-time PCR method was used to calculate the relative telomere length in 76 age-matched and sex-matched, newly diagnosed late-onset AD or VaD patients recruited from our Memory Unit. No significant difference was found in the relative telomere length between AD and VaD cases neither in men (P=0.315) nor women (P=0.12). Thus, we could not confirm that the length of telomeres would predict which form of dementia, late-onset AD or VaD that develops.

  • 42. Löf-Ohlin, Zarah M.
    et al.
    Sorbe, Bengt
    Wingren, Sten
    Örebro University, School of Health and Medical Sciences.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Hypermethylation of promoter regions of the APC1A and p16(INK4a) genes in relation to prognosis and tumor characteristics in cervical cancer patients2011In: International Journal of Oncology, ISSN 1019-6439, Vol. 39, no 3, p. 683-688Article in journal (Refereed)
    Abstract [en]

    Hypermethylation of the O(6)-MGMT, p14(ARF), p16(INK4a), RASSFIA and APC1A genes are unfavourable prognostic markers in colorectal cancer (CRC). We hypothesized that they could be related to prognosis also in cervical cancer. Methylation was studied in DNA extracts from surgical specimens of cancer tissue by novel pyrosequencing methods. In 109 patients (90 squamous cell carcinomas, 19 adenocarcinomas), we found that hypermethylation of the APC1A gene promoter occurred in 8.3% of patients, and of p16(INK4a) in 1.8%. APC1A hypermethylation was significantly related to more advanced FIGO stage of the tumor (P=0.013), larger tumor diameter (P=0.049) and distant recurrence-free survival (P=0.0007), but not with locoregional recurrence rate, age, HPV status, DNA ploidy, tumor grade or malignancy grading score. We conclude that methylation of the APC1A promoter in cervical cancer, as diagnosed by pyrosequencing, is significantly related to major biological characteristics of the tumor, and may be a new predictor of poor prognosis in cervical cancer.

  • 43. Löf-Öhlin, Zarah M.
    et al.
    Levanat, Sonja
    Sabol, Maja
    Sorbe, Bengt
    Örebro University, School of Health and Medical Sciences.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Promoter methylation in the PTCH gene in cervical epithelial cancer and ovarian cancer tissue as studied by eight novel Pyrosequencing (R) assays2011In: International Journal of Oncology, ISSN 1019-6439, Vol. 38, no 3, p. 685-692Article in journal (Refereed)
    Abstract [en]

    DNA methylation status in the CpG sites of promoter regions in cancer-related genes, such as PTCH, has traditionally been investigated using either dye-terminator sequencing or methylation-specific PCR. We aimed to study the PTCH gene promoter methylation in gynecological cancers with a method that gives a quantitative measure of the methylation status of the promoter region of the studied gene, and for this purpose, we designed novel Pyrosequencing-based assays. Bisulfite-treated genomic DNA (bsDNA) was amplified by standard PCR and applied to novel Pyrosequencing(R) assays, in order to measure the methylated fraction (%) at each CpG site of the PTCH gene promoter. We analyzed 22 squamous cell cervical cancer tissue specimens (11 with good and 11 with poor outcomes after radiotherapy) and 5 ovarian cancer tissue specimens matched with 5 normal ovarian tissue specimens. Six optimized PCR protocols which generated 8 Pyrosequencing assays covering 63 CpG sites in the promoter regions 1 and 2 as well as the previously unanalyzed promoter region 3 in the PTCH gene were developed. The 27 tumor tissue specimens and 5 normal tissues did not show any methylation within any of the 63 CpG sites. Our data suggest that methylation of the PTCH promoter is not a high-prevalence feature of squamous cell cervical cancer or ovarian cancer, but Pyrosequencing assays are a good method for studying promoter methylation.

  • 44. Löf-Öhlin, Zarah M.
    et al.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Pyrosequencing assays to study promoter CpG site methylation of the O6-MGMT, hMLH1, p14ARF, p16INK4a, RASSF1A, and APC1A genes2009In: Oncology Reports, ISSN 1021-335X, E-ISSN 1791-2431, Vol. 21, no 3, p. 721-729Article in journal (Refereed)
    Abstract [en]

    DNA methylation of CpG sites in promoter regions of several cancer related genes, such as O6-MGMT, hMLH1, p14ARF, p16INK4a, RASSF1A and APC1A, has been actively explored recently. Much of the data has been obtained using a variation of an allele-specific PCR assay known as methylation specific PCR. This technique is objectionable for a number of methodological limitations and drawbacks. We wanted to study the promoter regions of the above mentioned genes using bisulfite-treated genomic DNA amplified by PCR, using primers designed to bind only to CpG-free sequences. The methylated fraction (%) of each CpG site was measured by Pyrosequencing technology. For three of the genes, O6-MGMT, hMLH1 and p14ARF, two amplicons were designed to cover all relevant CpG sites. Several of the amplicons were analyzed by two different Pyrosequencing assays. In all, we designed nine optimized PCR protocols and 13 Pyrosequencing assays covering the promoters of all six studied genes. In all cases, standard PCR generated sufficient quantities of pure amplicons to be further analyzed by Pyrosequencing technology. Thus, a total of 119 CpG sites in six genes could be quantified. We conclude that standard PCR followed by Pyrosequencing is a workable, more specific and quantitative alternative to 'methylation specific' PCR. This approach provides a more comprehensive picture of the distribution of DNA methylation throughout the promoter regions of the studied set of six genes, which will be of benefit in oncological research.

  • 45.
    Makdoumi, Karim
    et al.
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Ophthalmology.
    Nilsson, Torbjörn K.
    Department of Medical Biosciences/Clinical Chemistry, Umeå University, Umeå, Sweden; Faculty of Medicine and Health Department of Biomedicine, Örebro University, Örebro, Sweden.
    Crafoord, Sven
    Örebro University, School of Medical Sciences. Department of Ophthalmology.
    Levels of beta-trace protein in optic disc pit with macular detachment2017In: Acta Ophthalmologica, ISSN 1755-375X, E-ISSN 1755-3768, Vol. 95, no 8, p. 815-819Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: To report beta-trace protein (βTP) levels in the subretinal fluid (SRF) of four patients with a macular detachment associated with optic disc pit (ODP).

    METHODS: Four patients with a serous retinal detachment involving the macula was operated by pars plana vitrectomy (PPV) with C2 F6 gas tamponade and peeling of internal limiting membrane (ILM). Patients with a follow-up period exceeding one year postoperatively were included in the study. The SRF was drained using a fine cannula without laser photocoagulation, and the samples were analysed using particle-enhancing nephelometry. The levels of βTP were compared to 20 routine cerebrospinal fluid (CSF) samples.

    RESULTS: In four of the five samples from SRF had relatively low βTP levels, with a mean concentration of 6.6 mg/l (range 2.0 to 23.1 mg/l) compared to 16.0 mg/l (range 6.3-26.8 mg/l) in CSF. The only SRF sample within the range corresponding to normal CSF was the first sample from patient 4, and the analysis of the renewed aspirate during the second operation was 2.8 mg/l. Postoperatively, the regression of SRF was slow, but regression of SRF in the foveal region took place in all cases; however, visual acuity (VA) was improved in only half of the patients.

    CONCLUSION: The results from the analysed SRF regarding βTP concentration in these patients indicate that the SRF in ODP is not identical to CSF, as the concentrations of βTP differ.

  • 46.
    Murto, T.
    et al.
    Uppsala Univ, Dept Womens & Childrens Hlth, Uppsala, Sweden.
    Skoog Svanberg, A.
    Uppsala Univ, Dept Womens & Childrens Hlth, Uppsala, Sweden.
    Yngve, Agneta
    Örebro University, School of Hospitality, Culinary Arts & Meal Science. Department of Biosciences and Nutrition, Karolinska Institutet, Huddinge, Sweden.
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Medical Biosciences, Umeå University, Umeå, Sweden.
    Altmäe, S.
    Competence Centre on Reproductive Medicine and Biology, Tartu, Estonia; Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain.
    Wånggren, K.
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Salumets, A.
    Competence Ctr Reprod Med & Biol, Tartu, Estonia; Univ Tartu, Inst Biomed, Tartu, Estonia.
    Stavreus-Evers, A.
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Folic acid supplementation and IVF pregnancy outcome in women with unexplained infertility2014In: Reproductive Biomedicine Online, ISSN 1472-6483, E-ISSN 1472-6491, Vol. 28, no 6, p. 766-772Article in journal (Refereed)
    Abstract [en]

    Folic acid supplements are commonly used by infertile women and lead to a positive folate status. However, the effect of folic acid supplements on pregnancy outcome in women with unexplained infertility has not been well investigated. This study evaluated folic acid supplement use and folate status in women with unexplained infertility in relation to pregnancy outcome. In addition, use of folic acid supplements and folate status were compared between women with unexplained infertility and fertile, nonpregnant control women. Women with unexplained infertility used significantly more folic acid supplements and had higher median total folic acid intake from supplements compared with fertile control women (both P < 0.001). Women with unexplained infertility also had significantly higher median plasma folate and lower median plasma homocysteine concentrations than fertile women (both P < 0.001), but folic acid supplementation or folate status were not related to pregnancy outcome in women with unexplained infertility. In conclusion, folic acid supplementation or good folate status did not have a positive effect on pregnancy outcome following infertility treatment in women with unexplained infertility.

  • 47.
    Murto, Tiina
    et al.
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Kallak, Theodora Kunovac
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Hoas, Annica
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Altmäe, Signe
    Department of Paediatrics, School of Medicine, University of Granada, Granada, Spain; Competence Centre on Reproductive Medicine and Biology.
    Salumets, Andres
    Competence Centre on Reproductive Medicine and Biology; Institute of Biomedicine, University of Tartu, Tartu, Estonia.
    Nilsson, Torbjörn K
    Department of Medical Biosciences, Umeå University, Umeå, Sweden.
    Skoog Svanberg, Agneta
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Wånggren, Kjell
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Yngve, Agneta
    Örebro University, School of Hospitality, Culinary Arts & Meal Science. Department of Biosciences and Nutrition, Karolinska Institute, Huddinge, Sweden.
    Stavreus-Evers, Anneli
    Department of Women’s and Children’s Health, Uppsala University, Uppsala, Sweden.
    Folic acid supplementation and methylenetetrahydrofolate reductase (MTHFR) gene variations in relation to IVF pregnancy outcome2014In: Acta Obstetricia et Gynecologica Scandinavica, ISSN 0001-6349, E-ISSN 1600-0412, Vol. 94, no 1, p. 65-71Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To study folic acid intake, folate status and pregnancy outcome after infertility treatment in women with different infertility diagnoses in relation to methylenetetrahydrofolate reductase (MTHFR) 677C>T, 1298A>C and 1793G>A polymorphisms. Also the use of folic acid supplements, folate status and the frequency of different gene variations were studied in women undergoing infertility treatment and fertile women.

    DESIGN: Observational study.

    SETTING: University hospital.

    POPULATION: Women undergoing infertility treatment and healthy, fertile, non-pregnant women.

    METHODS: A questionnaire was used to assess general background data and use of dietary supplements. Blood samples were taken to determine plasma folate and homocysteine levels, and for genomic DNA extraction. A comparison of four studies was performed to assess pregnancy outcome in relation to MTHFR 677 TT vs. CC, and 1298 CC vs. AA polymorphisms.

    MAIN OUTCOME MEASURES: Folic acid supplement intake, and plasma folate, homocysteine and genomic assays.

    RESULTS: Women in the infertility group used significantly more folic acid supplements and had better folate status than fertile women, but pregnancy outcome after fertility treatment was not dependent on folic acid intake, folate status or MTHFR gene variations.

    CONCLUSION: High folic acid intakes and MTHFR gene variations seem not associated with helping women to achieve pregnancy during or after fertility treatment.

  • 48. Nilsson, Johan B.
    et al.
    Boman, Kurt
    Jansson, Jan-Håkan
    Nilsson, Torbjörn K.
    Örebro University, School of Health and Medical Sciences.
    Näslund, Ulf
    The influence of acute-phase levels of haemostatic factors on reperfusion and mortality in patients with acute myocardial infarction treated with streptokinase2008In: Journal of Thrombosis and Thrombolysis, ISSN 0929-5305, E-ISSN 1573-742X, Vol. 26, no 3, p. 188-195Article in journal (Refereed)
    Abstract [en]

    Background The fibrinolytic system and von Willebrand factor (vWF) have been shown to play a role as risk factors for myocardial infarction. We performed this prospective cohort study to determine if components in the fibrinolytic system or vWF before or during treatment of AMI with streptokinase (SK) could predict reperfusion, recurrent ischaemia, reinfarction or mortality at one year, or mortality at five years. Reperfusion and recurrent ischaemia were assessed by continuous vectorcardiography. The setting was Umeå university hospital and Skellefteå county hospital, Sweden. Results 139 patients were included; successful reperfusion was obtained in 53%. tPA activity, PAI-activity, PAI-mass concentration and vWF were analysed immediately on arrival and after 4 and 10 h. High fibrinolytic activity, measured as tPA activity > 25 U/L after the start of treatment, was associated with reperfusion. No significant associations between pre-treatment levels of the fibrinolytic variables or vWF and reperfusion or recurrent ischaemia were found. Elevated levels of PAI-1 mass concentration and PAI-1 activity after the start of SK treatment were associated with a higher risk for death at one year, but not at five years. High levels of vWF were associated with worse prognosis but not when corrected for age. Conclusion Pre-treatment levels of PAI-1, vWF and tPA activity showed no association with reperfusion or recurrent ischaemia. Elevated levels of PAI-1 activity after the start of treatment were associated with worse prognosis.

  • 49.
    Nilsson, Torbjorn K.
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Lof-Ohlin, Zarah M.
    Sun, Xiao-Feng
    DNA methylation of the p14(ARF), RASSF1A and APC1A genes as an independent prognostic factor in colorectal cancer patients2013In: International Journal of Oncology, ISSN 1019-6439, Vol. 42, no 1, p. 127-133Article in journal (Refereed)
    Abstract [en]

    We quantitated the methylated fraction of CpG sites in the promoter regions of O-6-MGMT, p14(ARF), p16(INK4a), RASSF1A and APC1A in tumor tissue from patients with colorectal cancer (CRC) in order to determine if promoter hypermethylation of any of these genes predicts survival. DNA was isolated from 111 primary CRC and 46 matched normal colorectal mucosa samples from the same patients, obtained at primary surgery and DNA methylation was examined by Pyrosequencing (R). Follow-up time was up to 20 years. Patients showed partial promoter methylation in the following frequencies: O-6-MGMT, 34%; p14(ARF), 29%; p16(INK4a), 28%; RASSF1A, 14%; and APC1A, 27%. Normal mucosa was always unmethylated. CRC patients with methylated p14(ARF). gene promoter had significantly worse prognosis (p=0.036), whereas those with methylated O-6-MGMT had significantly better prognosis through the first 60 months post-treatment (RR 0.36; p=0.023). Methylation of one or more of the genes from the set p14(ARF), RASSF1A and APC1A, was significantly (p=0.021) associated with worse prognosis even adjusting for tumor stage and differentiation (RR 2.2, p=0.037). Thus, DNA methylation of the p14(ARF), RASSF1A and APC1A genes, diagnosed by Pyrosequencing, defines a poor prognosis subset of CRC patients independently of both tumor stage and differentiation. O-6-MGMT methylation may play a protective role.

  • 50.
    Nilsson, Torbjörn, K.
    et al.
    Department of Laboratory Medicine, Örebro University Hospital, Örebro, Sweden.
    Hagnelius, Nils-Olof
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden.
    Folate in dementia and cognitive dysfunction2011In: Vitamins in the prevention of human diseases / [ed] Wolfgang Herrmann and Rima Obeid, Berlin, Germany: De Gruyter , 2011, 1, p. 125-140Chapter in book (Refereed)
12 1 - 50 of 63
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