Jens Petter Berg

• Svetlana Zykova, Anna Plaksienko, Anne Lee Solevåg, Anne Karin Brigtsen, Trond Melbye Michelsen & Ingvil Krarup Sørbye [Vis alle 12 forfattere av denne artikkelen] (2026). Neonatal reference intervals for salivary steroids: focus on prematurity, stressful events and perinatal betamethasone. Frontiers in Pediatrics. 14. doi: 10.3389/fped.2026.1808446. Fulltekst i vitenarkiv
• Kristin Godang, Maren Ileby Wessel, Yusuf Khan, Thor Ueland, Tove Lekva & Jens Petter Berg [Vis alle 8 forfattere av denne artikkelen] (2026). Targeted proteomics reveals novel biomarkers of disease activity and inflammation in acromegaly. European Journal of Endocrinology (EJE). ISSN 0804-4643. 194(5), s. 732–743. doi: 10.1093/ejendo/lvag083. Fulltekst i vitenarkiv
• Anne Hansen Ree, Paula Bousquet, Martina Visnovska, Torben Lüders, Benjamin Peter Geisler & Shixiong Wang [Vis alle 16 forfattere av denne artikkelen] (2026). Exploratory biomarkers for oxaliplatin-induced nivolumab responsiveness in metastatic microsatellite-stable colorectal cancer. British Journal of Cancer. ISSN 0007-0920. 134, s. 1176–1182. doi: 10.1038/s41416-026-03357-6. Fulltekst i vitenarkiv Vis sammendrag

  ABackground The randomised METIMMOX trial evaluated short-course oxaliplatin-based chemotherapy alternating with nivolumab for metastatic microsatellite-stable/mismatch repair-proficient colorectal cancer. In a post hoc analysis, we investigated whether tumour mutations or patients’ systemic inflammation might provide insights into responsiveness to the METIMMOX regimen. Methods Patients received either oxaliplatin-based chemotherapy (control group) or alternating two cycles each of chemotherapy and nivolumab (experimental group), with progression-free survival (PFS) as the primary endpoint. Tumour biopsies were sequenced with the TruSight Oncology 500 assay. Results The median tumour mutational burden (TMB; in mutations/megabase) was 8 (range, 1–13). The experimental-arm patients with TMB ≥9 or BRAF -V600E mutation ( n  = 17) achieved median PFS of 19.8 months (95% confidence interval, 11.3–28.3), longer ( p  = 0.0090) than experimental-arm patients with TMB < 9 not BRAF -V600E ( n  = 19) and control-arm patients with either TMB and BRAF status combination ( n  = 31). With TMB ≥9 or BRAF -V600E and normal, non-inflammatory level of C-reactive protein when starting nivolumab ( n  = 11), median PFS was 35.0 months (95% confidence interval, 6.8–63.0; p  < 0.0001). Conclusions TMB, somatic BRAF status and systemic inflammation should be prospectively investigated as practical biomarkers for predicting potential responsiveness to immune checkpoint inhibitors in metastatic microsatellite-stable/mismatch repair-proficient colorectal cancer.

• Christin Waage, Anne Karen Jenum, Ibrahimu Mdala, Sindre Lee-Ødegård, Anja Maria Brænd & Line Sletner [Vis alle 8 forfattere av denne artikkelen] (2025). Diabetes and prediabetes among women universally screened for gestational diabetes: a multi-ethnic, population-based, prospective study with eleven years follow-up. BMC Public Health. 25(1). doi: 10.1186/s12889-025-22493-x. Fulltekst i vitenarkiv Vis sammendrag

  Background Gestational diabetes (GDM) is a strong risk factor for later development of diabetes. However, data are scarce on the long-term risk for diabetes or prediabetes diagnosed by HbA1c, in non-selected, multi-ethnic populations universally screened for GDM using the WHO2013 criteria. We aimed to investigate the development of diabetes or prediabetes eleven years after the index pregnancy and identify risk factors in pregnancy or shortly after. Methods A population-based cohort study of 360 women with complete eleven years follow-up data for diabetes (HbA1c≥48 mmol/mol) or prediabetesADA (HbA1c 39–47 mmol/mol). Women were enrolled in gestational week 15 and universally screened with an oral glucose tolerance test in week 28. We performed least absolute shrinkage and selection operator (LASSO) regression to identify predictors of future diabetes or prediabetesADA and constructed a nomogram to predict individual risks. Results Diabetes or prediabetesADA combined, was found in 26.9%, and the prevalence was slightly higher in previous GDM compared with non-GDM women (35.6% versus 23.5%; p=0.019). The relative risk (RR) for developing diabetes or prediabetesADA was moderately elevated in GDM compared with non-GDM women (1.4 [1.0, 1.9], p=0.035). Seven women (1.9%) had diabetes and all of these except for one, had previous GDM. Hence, the crude prevalence was 5.8% among GDM women vs. 0.4% among non-GDM women. The RR for developing diabetes was substantially higher in GDM vs. non-GDM women (14.8 [2.6, 277.1], p=0.012). PrediabetesADA was found in 25% and the RR for prediabetesADA was not significantly increased for GDM compared to non-GDM women (1.3 [0.9, 1.8], p=0.143). Among Europeans, 17.0% had diabetes or prediabetesADA, compared to 43.0% among South Asians (p<0.001) and 34.4% among other ethnicities (p=0.002). The most significant predictors identified from the LASSO were HbA1c measured in early pregnancy, ethnicity, and a family history of diabetes. Conclusions The risk for developing diabetes was low, overall and among GDM women. Still GDM represented a strong risk for diabetes, but not for prediabetesADA. HbA1c early in pregnancy, non-European ethnicity, and a family history of diabetes were the strongest risk factors for developing diabetes or prediabetesADA.

• Dennis van der Meer, Mohammad Zillur Rahman, Aigar Ottas, Pravesh Parekh, Gleda Kutrolli & Sara Elizabeth Stinson [Vis alle 37 forfattere av denne artikkelen] (2025). Pleiotropic and sex-specific genetic mechanisms of circulating metabolic markers. Nature Communications. 16(1). doi: 10.1038/s41467-025-60058-z. Fulltekst i vitenarkiv Vis sammendrag

  Metabolites in plasma form biosignatures of a range of common complex human diseases. Discovering variants with pleiotropic effects across metabolites can reveal underlying biological mechanisms. We therefore performed uni- and multivariate genome-wide association studies (GWAS) on 249 circulating metabolic markers across 328,006 UK Biobank and Estonian Biobank participants. We investigated rare variation through whole exome sequencing gene burden tests, analysed the role of body mass index through Mendelian randomization, and performed genome-wide interaction analyses with sex. We discovered 15,585 loci summed over the univariate GWAS, with high pleiotropy across markers, linked to a wide range of disorders. Findings from common and rare variant gene tests converged on lipid homeostasis pathways. 31 loci interacted with sex, mapped to genes involved in cholesterol processing. The findings offer insights into the genetic architecture of circulating metabolites, revealing pleiotropic loci, highlighting the role of rare variation, and uncovering sex-specific molecular mechanisms of lipid metabolism.

• Merisa Abusdal, Kjersti Normann Markussen, Tuula A Nyman, Kristin Astrid Berland Øystese, Arvind Sundaram & Daniel Dahlberg [Vis alle 10 forfattere av denne artikkelen] (2024). PCSK1N as a Tumor Size Marker and an ER Stress Response Protein in Corticotroph Pituitary Adenomas. Journal of Clinical Endocrinology and Metabolism (JCEM). ISSN 0021-972X. 110(4), s. 1065–1075. doi: 10.1210/clinem/dgae643. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Context Silent corticotroph adenoma (SCA) exhibits more tumor aggressiveness features than functioning adenomas (FCAs). Objective We aimed to investigate proprotein convertase subtilisin/kexin type 1 inhibitor (PCSK1N) expression in CA and examine if endoplasmic reticulum (ER) stress-induced responses affect cell survival in a corticotroph tumor cell model. Methods Clinical and imaging characteristics were recorded in 33 patients with FCA (20 women, 11 macroadenomas) and 18 SCAs (8 women, all macroadenomas). Gene expression of pro-opiomelanocortin (POMC), T-box transcription factor 19(TBX19)/TPIT, proprotein convertase subtilisin/kexin type 1 (PCSK1)/PC1/3, and its inhibitor PCSK1N, was measured by reverse transcription–quantitative polymerase chain reaction in adenoma tissue. Mouse pituitary corticotroph tumor (AtT-20) cells were treated with tanespimycin (17-AAG), an HSP90 chaperone inhibitor, to induce ER stress, followed by gene and protein analyses. Results POMC, TPIT, and PCSK1 expression were higher, whereas PCSK1N was lower in FCA compared to SCA. PCSK1N correlated with POMC (rs = −0.514; P &lt; .001), TPIT (rs = −0.386; P = .005), PCSK1 (rs = −0.3691; P = .008), and tumor largest diameter (rs = 0.645; P &lt; .001), in all CA. Induction of ER stress by 17-AAG in AtT-20 cells led to a decrease of Pomc and an increase of Pcsk1n gene expression at 24 hours. Moreover, a downregulation of cell cycle, apoptosis, and senescence pathways, and alterations in cell adhesion and cytoskeleton, were observed at the protein level. Conclusion PCSK1N is higher in SCA compared with FCA, and associated with corticotroph cell markers and tumor size. PCSK1N is likely to be part of the adaptive response to ER stress, potentially conferring a survival advantage to the corticotroph tumor cell in conjunction with other proteins.

• Anne Hansen Ree, Jurate Saltyte Benth, Hanne Mari Hamre, Christian Kersten, Eva Hofsli & Marianne Guren [Vis alle 14 forfattere av denne artikkelen] (2024). First-line oxaliplatin-based chemotherapy and nivolumab for metastatic microsatellite-stable colorectal cancer—the randomised METIMMOX trial. British Journal of Cancer. ISSN 0007-0920. 130(12), s. 1921–1928. doi: 10.1038/s41416-024-02696-6. Fulltekst i vitenarkiv Vis sammendrag

  Background We evaluated first-line treatment of metastatic microsatellite-stable colorectal cancer with short-course oxaliplatin-based chemotherapy alternating with immune checkpoint blockade. Methods Patients were randomly assigned to chemotherapy (the FLOX regimen; control group) or alternating two cycles each of FLOX and nivolumab (experimental group). Radiographic response assessment was done every eight weeks with progression-free survival (PFS) as the primary endpoint. Cox proportional-hazards regression models estimated associations between PFS and relevant variables. A post hoc analysis explored C-reactive protein as signal of responsiveness to immune checkpoint blockade. Results Eighty patients were randomised and 38 in each group received treatment. PFS was comparable—control group: median 9.2 months (95% confidence interval (CI), 6.3–12.7); experimental group: median 9.2 months (95% CI, 4.5–15.0). The adjusted Cox model revealed that experimental-group subjects aged ≥60 had significantly lowered progression risk (p = 0.021) with hazard ratio 0.17 (95% CI, 0.04–0.76). Experimental-group patients with C-reactive protein <5.0 mg/L when starting nivolumab (n = 17) reached median PFS 15.8 months (95% CI, 7.8–23.7). One-sixth of experimental-group cases (all KRAS/BRAF-mutant) achieved complete response. Conclusions The investigational regimen did not improve the primary outcome for the intention-to-treat population but might benefit small subgroups of patients with previously untreated, metastatic microsatellite-stable colorectal cancer. Trial registration ClinicalTrials.gov number, NCT03388190 (02/01/2018).

• Paul Denver, Lucas Tortorelli, Karen Roksund Hov, Jens Petter Berg, Lasse Melvær Giil & Arshed Nazmi [Vis alle 12 forfattere av denne artikkelen] (2024). Chemokine associations with blood cerebrospinal fluid (CSF) barrier permeability and delirium. Brain, Behavior, and Immunity - Health (BBI - Health). 43, s. 1–13. doi: 10.1016/j.bbih.2024.100920. Fulltekst i vitenarkiv Vis sammendrag

  Delirium is a highly prevalent neuropsychiatric syndrome characterised by acute and fluctuating impairments in attention and cognition. Mechanisms driving delirium are poorly understood but it has been suggested that blood cytokines and chemokines cross the blood brain barrier during delirium, directly impairing brain function. It is not known whether these molecules reach higher brain levels when the blood cerebrospinal fluid barrier (BCSFB) is impaired. Here, in human hip-fracture patients, we tested the influence of BCSFB integrity on CSF levels of chemokines and assessed their association with delirium. CSF levels of IP-10, eotaxin, eotaxin 3 and TARC showed weak to moderate correlations with BCSFB permeability, as measured by the Qalbumin ratio, while MCP1, IL-8, MIP1α and MIP1β showed no significant correlation. Chemokines were not associated with delirium in univariate analysis or when stratified on dementia status, but exploratory analyses showed that elevated Eotaxin (CCL11) and MIP1α (CCL3) were associated with prevalent delirium. Modelling acute systemic inflammation, we used bacterial LPS (250 μg/kg) or sterile laparotomy surgery in mice to demonstrate de novo synthesis of chemokines at the choroid plexus (CP) and microvasculature. Gene expression data showed CP-enriched expression of Il1b, Tnfa, Cxcl1 and Ccl3 in both models and immunohistochemistry showed cytokine and chemokine synthesis in CP stromal (IL-1β, CCL2/MCP1) or epithelial cells (CXCL10/IP-10) cells and at the microvasculature. Larger studies are required to confirm these human findings on chemokine associations with BCSFB permeability and prevalent delirium. Preclinical studies are warranted to determine whether chemokines might play a role in the pathophysiology of delirium.

• Kristin Astrid Berland Øystese, Nicoleta Cristina Olarescu, Cecilia Lindskog, Fabjola Xheka, Jon Berg-Johnsen & Jens Petter Berg [Vis alle 8 forfattere av denne artikkelen] (2024). Stem cell-associated transcription factors in non-functioning pituitary neuroendocrine tumours. Free Neuropathology. 5. doi: 10.17879/freeneuropathology-2024-5396. Fulltekst i vitenarkiv Vis sammendrag

  Background: Cells with stem cell features have been described in pituitary neuroendocrine tumours (PitNETs). Transcription factors SOX2 and SOX9 are stem cell-associated markers while the pituitary progenitor marker PROP1 is involved in anterior pituitary development. We characterised the presence of these markers known to be present in the human pituitary in non-functioning (NF) PitNETs. Methods: We investigated the pituitary transcription factors SOX2, SOX9 and PROP1 by immunohistochemistry (IHC) (N = 125) and RT-qPCR (N = 78) in a retrospective cohort of clinically NF-PitNETs. The markers were scored based on the percentage of immunolabeled cells. IHC staining scores were compared to reintervention rates for the whole cohort, and to expression of FSH, LH or ER in gonadotroph NF-PitNETs. Results: Most tumours showed no or few cells positive for SOX2, SOX9 and PROP1. More patients with SOX2-negative tumours went through reintervention (40 % vs 19 %, p = 0.03). SOX2, SOX9 and PROP1 staining correlated positively to each other (SOX2 and SOX9 rs = 0.666, SOX2 and PROP1 rs = 0.704, SOX9 and PROP1 rs = 0.570, and p < 0.001 for all). In gonadotroph NF-PitNETs, staining for SOX2 and PROP1 was positively associated to FSHβ staining (p < 0.001 for both). Staining for SOX2, SOX9 and PROP1 was positively associated with gene expression of Estrogen Receptor 1 (ESR1) (p < 0.001, p = 0.004 and p < 0.001) and IHC staining for ERα (p = 0.001, p = 0.03 and p = 0.05, respectively). Conclusion: SOX2, SOX9 and PROP1 were present at low levels in NF-PitNETs. Absence of SOX2 staining was associated with a higher reintervention rate. The stem cell markers correlated positively with markers of gonadotroph differentiation in gonadotroph NF-PitNETs. SOX2 and SOX9 were frequently coexpressed and showed positivity in intratumoural cells with epithelial features, however without coexpression of pituitary transcription factors.

• Marthe-Lise Næss-Andresen, Anne Karen Jenum, Jens Petter Berg, Ragnhild Sørum Falk & Line Sletner (2023). The impact of recommending iron supplements to women with depleted iron stores in early pregnancy on use of supplements, and factors associated with changes in iron status from early pregnancy to postpartum in a multi-ethnic population-based cohort. BMC Pregnancy and Childbirth. 23:350(1), s. 1–13. doi: 10.1186/s12884-023-05668-5. Fulltekst i vitenarkiv Vis sammendrag

  Background We aimed to evaluate the impact of recommending supplementation to pregnant women with serum ferritin (SF) < 20 µg/L in early pregnancy on use of supplements, and to explore which factors were associated with changes in iron status by different iron indicators to 14 weeks postpartum. Methods A multi-ethnic population-based cohort study of 573 pregnant women examined at mean gestational week (GW) 15 (enrolment), at mean GW 28 and at the postpartum visit (mean 14 weeks after delivery). Women with SF < 20 µg/L at enrolment were recommended 30-50 mg iron supplementation and supplement use was assessed at all visits. Change of SF, soluble transferrin receptor and total body iron from enrolment to postpartum were calculated by subtracting the concentrations at the postpartum visit from that at enrolment. Linear and logistic regression analyses were performed to assess associations between use of supplements in GW 28 and changes in iron status and postpartum iron deficiency/anaemia. Change of iron status was categorized into ‘steady low’, ‘improvement’, ‘deterioration’, and ‘steady high’ based on SF status at enrolment and postpartum. Multinomial logistic regression analyses were performed to identify factors associated with change of iron status. Results At enrolment, 44% had SF < 20 µg/L. Among these women (78% non-Western European origin), use of supplements increased from 25% (enrolment) to 65% (GW 28). Use of supplements in GW 28 was associated with improved iron levels by all three indicators (p < 0.05) and with haemoglobin concentration (p < 0.001) from enrolment to postpartum, and with lower odds of postpartum iron deficiency by SF and TBI (p < 0.05). Factors positively associated with ‘steady low’ were: use of supplements, postpartum haemorrhage, an unhealthy dietary pattern and South Asian ethnicity (p ≤ 0.01 for all); with ‘deterioration’: postpartum haemorrhage, an unhealthy dietary pattern, primiparity and no use of supplements (p < 0.01 for all), and with ‘improvement’: use of supplements, multiparity and South Asian ethnicity (p < 0.03 for all). Conclusions Both supplement use and iron status improved from enrolment to the postpartum visit among women recommended supplementation. Dietary pattern, use of supplements, ethnicity, parity and postpartum haemorrhage were identified as factors associated with change in iron status.

• Marthe-Lise Næss-Andresen, Anne Karen Jenum, Jens Petter Berg, Ragnhild Sørum Falk & Line Sletner (2022). Prevalence of postpartum anaemia and iron deficiency by serum ferritin, soluble transferrin receptor and total body iron, and associations with ethnicity and clinical factors: a Norwegian population-based cohort study. Journal of Nutritional Science (JNS). 11. doi: 10.1017/jns.2022.45. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Worldwide, there are limited data on the prevalence of postpartum anaemia and iron status. The aims of the present study were to assess the prevalence of anaemia and iron deficiency (ID) by three iron indicators 14 weeks postpartum, their relations to haemoglobin (Hb) and associations with ethnicity and clinical factors in a multi-ethnic population. We conducted a population-based cohort study of 573 women followed from early pregnancy. The prevalence of postpartum anaemia (Hb &lt;12·0 g/dl) was 25 %. ID prevalence varied from 39 % by serum ferritin (SF &lt;15 μg/l), to 19 % by soluble transferrin receptor (sTfR &gt;4·4 mg/l) and 22 % by total body iron (TBI &lt; 0 mg/kg). The mean Hb concentration was 12·8 g/dl in women with no ID, 12·6 g/dl in those with ID by SF only and 11·6 g/dl in those with ID by SF, sTfR and TBI. ID by sTfR and TBI defined by the current threshold values probably identified a more severe iron-deficient population compared with ID assessed by SF. Compared with Western Europeans, the prevalence of anaemia was at least the double in ethnic minorities (26–40 % v . 14 %; P &lt; 0·01–0·05), and the prevalence of ID by sTfR and TBI, but not of ID by SF &lt; 15 μg/l, was significantly higher in some minority groups. After adjustment for covariates, only South Asians had lower Hb and higher sTfR concentration. Insufficient iron intake, gestational anaemia or ID, and postpartum haemorrhage were associated with lower postpartum Hb concentration and poorer iron status.

• Kristin Astrid Berland Øystese, Olivera Casar-Borota, Jon Berg-Johnsen, Jens Petter Berg & Jens Bollerslev (2022). Distribution of E- and N-cadherin in subgroups of non-functioning pituitary neuroendocrine tumours. Endocrine. ISSN 1355-008X. 77(1), s. 151–159. doi: 10.1007/s12020-022-03051-6. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Purpose Clinically non-functioning pituitary neuroendocrine tumours (NF-PitNETs) present a varying degree of aggressiveness, and reliable prognostic markers are lacking. We aimed to characterise the distribution of E- and N-cadherin in corticotroph, PIT1 and null-cell NF-PitNETs, and link it to the course of the tumours. Methods The distribution of E- and N-cadherin was investigated by immunohistochemistry in a retrospective cohort of 30 tumours of the less common NF-PitNETs (corticotroph ( N  = 18), PIT1 ( N  = 8) and null-cell PitNETs ( N  = 4)). Immunoreactive scores (IRS) were compared to previously presented cohorts of gonadotroph NF-PitNETs ( N  = 105) and corticotroph functioning PitNETs ( N  = 17). Results We found a low IRS for the extra-cellular domain of E-cadherin (median 0 (IQR 0–0, N  = 135)), a medium to high IRS for the intra-cellular domain of E-cadherin (median 6 (IQR 4–9)) and a high IRS for N-cadherin (median 12 (IQR 10.5–12)) throughout the cohort of NF-PitNETs. The corticotroph NF-PitNETs presented a higher IRS for both the extra- and intra-cellular domain of E-cadherin (median 0 (IQR 0–1) and median 9 (IQR 6–12), respectively) than the gonadotroph NF-PitNETs ( p  &lt; 0.001 for both comparisons). Presence of nuclear E-cadherin was associated with a weaker staining for the intra-cellular domain of E-cadherin (median 4 (IQR 0.5–6) and median 9 (IQR 9–12), for tumours with and without nuclear E-cadherin, respectively), and with a lower rate of re-intervention ( p  = 0.03). Conclusions Considering our results and the benign course of NF-PitNETs, we suggest that a high N-cadherin and downregulation of membranous E-cadherin are not associated with a more aggressive tumour behaviour in these subgroups of NF-PitNETs.

• Aina Jansen, Jan Olav Aaseth, Jan Ludvig Lyche, Jens Petter Berg, Mette Helen Bjørge Müller & Stian Lydersen [Vis alle 7 forfattere av denne artikkelen] (2022). Do changes in persistent organic pollutants after bariatric surgery cause endocrine disruption? Chemosphere. ISSN 0045-6535. 313, s. 1–8. doi: 10.1016/j.chemosphere.2022.137461. Fulltekst i vitenarkiv Vis sammendrag

  Background Bariatric surgery results in weight loss, marked endocrine changes and the release of persistent organic pollutants (POPs). The release of POPs might cause endocrine disruption. The study aimed to explore associations between POPs and adiponectin, leptin and ghrelin in subjects undergoing bariatric surgery. Methods: The study included 63 subjects with severe obesity (men/women: 13/50), age (years): 45.0 (8.5), and BMI (kg/m2) 39.1 (3.4). Analyses of adiponectin, leptin and ghrelin and POPs (hexachlorobenzene (HCB), dichlorodiphenyldichloroethylene (p,p’-DDE), polychlorinated biphenyl (PCB) 118 (dioxin-like compound; dl), and sum 6 PCB (PCB 28, -52, −101, −138, −153, and −180) were performed before and 12 months after bariatric surgery. Results: There were significant increases in adiponectin and all POPs and a fall in leptin after surgery. The main finding was the highly significant associations between adiponectin and all POPs. The increase in HCB explained 38% of the variation in adiponectin. Conclusions: If the POP-associated increase in adiponectin is a causal effect, the release of POPs might have important clinical consequences. Adiponectin has both positive and negative clinical effects exerted by essentially unknown mechanisms. The effects of released POPs on the metabolic functions in subjects undergoing bariatric surgery deserve further evaluation. © 2022 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

• Birgitte Kordt Sundet, Ina Kreyberg, Anne Cathrine Staff, Karin Cecilie Lødrup Carlsen, Karen Eline Stensby Bains & Jens Petter Berg [Vis alle 20 forfattere av denne artikkelen] (2022). The effect of nicotine-containing products and fetal sex on placenta-associated circulating midpregnancy biomarkers. Biology of Sex Differences. 13(1). doi: 10.1186/s13293-022-00443-1. Fulltekst i vitenarkiv Vis sammendrag

  In utero exposure to nicotine, largely assessed by smoking, is a risk factor for impaired offspring health, while potential effects of non-combustible nicotine use such as snus (oral moist tobacco), are less well-known. Maternal serum concentrations of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) may be viewed as “placenta health markers”, known to differ by fetal sex. Maternal smoking during pregnancy has been associated with lower levels of circulating sFlt-1, while the effect of snus on placenta-associated angiogenic factors is unknown. Our aim was to explore if snus and/or smoking exposure was associated with midpregnancy maternal levels of sFlt-1, PlGF and sFlt-1/PlGF ratio if these associations were modified by fetal sex. Methods Midpregnancy (16–22 gestational weeks) serum from 2603 Scandinavian women enrolled in the population-based multi-center PreventADALL (Preventing Atopic Dermatitis and ALLergies in children) study was analysed for sFlt-1 and PlGF concentrations by electrochemiluminescence, deriving the sFlt-1/PGF ratio. Nicotine use was assessed by electronic questionnaires at enrollment in 2278 of the women. Univariable and multivariable linear regression models on log transformed outcomes were used to assess the association between nicotine use and biomarker levels. Interaction terms were included to identify whether the associations were modified by fetal sex. Results Median sFlt-1, PlGF and sFlt-1/PlGF ratios among women with nicotine exposure information were similar to those of all included women and differed by fetal sex. Current snus use was significantly associated with reduced maternal circulating PlGF levels in adjusted analyses [β − 0.12, (95% CI − 0.20; 0.00) compared to never use, p = 0.020]. A significant interaction between fetal sex and snus exposure was observed for PIGF (p = 0.031). Prior or periconceptional snus use was significantly associated with PIGF in male fetus pregnancies [β − 0.05 (95% CI − 0.09 to (− 0.02)) and β − 0.07 (95% CI − 0.12 to (− 0.02)) compared to never use, p = 0.002]. Smoking was not significantly associated with any circulating biomarkers levels. Conclusions Midpregnancy maternal angiogenic profile differed by periconceptional snus use and fetal sex. Snus exposure, perceived as “safe” by users, before or during pregnancy seems to affect midpregnancy placental health in a sex dimorphic manner.

• Kristina Wendel, Helle Cecilie Pfeiffer, Drude Fugelseth, Eirik Nestaas, Magnus Domellöf & Bjørn Steen Skålhegg [Vis alle 42 forfattere av denne artikkelen] (2021). Effects of nutrition therapy on growth, inflammation and metabolism in immature infants: a study protocol of a double-blind randomized controlled trial (ImNuT). BMC Pediatrics. 21. doi: 10.1186/s12887-020-02425-x. Fulltekst i vitenarkiv Vis sammendrag

  Background: Current nutritional management of infants born very preterm results in significant deficiency of the essential fatty acids (FAs) arachidonic acid (ARA) and docosahexaenoic acid (DHA). The impact of this deficit on brain maturation and inflammation mediated neonatal morbidities are unknown. The aim of this study is to determine whether early supply of ARA and DHA improves brain maturation and neonatal outcomes in infants born before 29 weeks of gestation. Methods: Infants born at Oslo University Hospital are eligible to participate in this double-blind randomized controlled trial. Study participants are randomized to receive an enteral FA supplement of either 0.4 ml/kg MCT-oil™ (medium chain triglycerides) or 0.4 ml/kg Formulaid™ (100 mg/kg of ARA and 50 mg/kg of DHA). The FA supplement is given from the second day of life to 36 weeks' postmenstrual age (PMA). The primary outcome is brain maturation assessed by Magnetic Resonance Imaging (MRI) at term equivalent age. Secondary outcomes include quality of growth, incidence of neonatal morbidities, cardiovascular health and neuro-development. Target sample size is 120 infants (60 per group), this will provide 80% power to detect a 0.04 difference in mean diffusivity (MD, mm2/sec) in major white matter tracts on MRI. Discussion: Supplementation of ARA and DHA has the potential to improve brain maturation and reduce inflammation related diseases. This study is expected to provide valuable information for future nutritional guidelines for preterm infants. Trial registration: Clinicaltrials.gov ID: NCT03555019 . Registered 4 October 2018- Retrospectively registered.

• Ingrid Nygren Rognes, Søren Erik Pischke, William Ottestad, Jo Røislien, Jens Petter Berg & Christina Johnson [Vis alle 8 forfattere av denne artikkelen] (2021). Increased complement activation 3 to 6 h after trauma is a predictor of prolonged mechanical ventilation and multiple organ dysfunction syndrome: a prospective observational study. Molecular medicine (Cambridge, Mass. Print). ISSN 1076-1551. 27(1), s. 1–13. doi: 10.1186/s10020-021-00286-3. Fulltekst i vitenarkiv Vis sammendrag

  Background - Complement activation is a central mechanism in systemic inflammation and remote organ dysfunction following major trauma. Data on temporal changes of complement activation early after injury is largely missing. We aimed to describe in detail the kinetics of complement activation in individual trauma patients from admission to 10 days after injury, and the association with trauma characteristics and outcome. Methods - In a prospective cohort of 136 trauma patients, plasma samples obtained with high time resolution (admission, 2, 4, 6, 8 h, and thereafter daily) were assessed for terminal complement complex (TCC). We studied individual TCC concentration curves and calculated a summary measure to obtain the accumulated TCC response 3 to 6 h after injury (TCC-AUC3–6). Correlation analyses and multivariable linear regression analyses were used to explore associations between individual patients’ admission TCC, TCC-AUC3–6, daily TCC during the intensive care unit stay, trauma characteristics, and predefined outcome measures. Results - TCC concentration curves showed great variability in temporal shapes between individuals. However, the highest values were generally seen within the first 6 h after injury, before they subsided and remained elevated throughout the intensive care unit stay. Both admission TCC and TCC-AUC3–6 correlated positively with New Injury Severity Score (Spearman’s rho, p-value 0.31, 0.0003 and 0.21, 0.02) and negatively with admission Base Excess (− 0.21, 0.02 and − 0.30, 0.001). Multivariable analyses confirmed that deranged physiology was an important predictor of complement activation. For patients without major head injury, admission TCC and TCC-AUC3–6 were negatively associated with ventilator-free days. TCC-AUC3–6 outperformed admission TCC as a predictor of Sequential Organ Failure Assessment score at day 0 and 4. Conclusions - Complement activation 3 to 6 h after injury was a better predictor of prolonged mechanical ventilation and multiple organ dysfunction syndrome than admission TCC. Our data suggest that the greatest surge of complement activation is found within the first 6 h after injury, and we argue that this time period should be in focus in the design of future experimental studies and clinical trials using complement inhibitors.

• Karl Arne Johannessen, Nina Kristin Steen Wear, Karin Toska, Morten Hansbø, Jens Petter Berg & Erik Fosse (2021). Pathologic Blood Samples Tolerate Exposure to Vibration and High Turbulence in Simulated Drone Flights, but Plasma Samples Should be Centrifuged after Flight. IEEE Journal of Translational Engineering in Health and Medicine. doi: 10.1109/JTEHM.2021.3053172. Fulltekst i vitenarkiv Vis sammendrag

  Objective. Most of the previous studies of drone transport of blood samples examined normal blood samples transported under tranquil air conditions. We studied the effects of 1- and 2-hour drone flights using random vibration and turbulence simulation (10-30 g-force) on blood samples from 16 healthy volunteers and 74 patients with varying diseased. Methods: Thirty-two of the most common analytes were tested. For biochemical analytes, we used plasma collected in lithium heparin tubes with and without separator gel. Gel samples were analyzed for the effect of separation by centrifugation before or after turbulence. Turbulence was simulated in an LDS V8900 high-force shaker using random vibration (range, 5-200 Hz), with samples randomly allocated to 1- or 2-hour flights with 25 or 50 episodes of turbulence from 10 to 30 G. Results: For all hematologic and most biochemical analytes, test results before and after turbulence exposure were similar (bias <; 12%, intercepts <; 10%). However, aspartate aminotransferase, folate, lactate dehydrogenase and lipid index increased significantly in samples separated by gel and centrifugation prior to vibration and turbulence test. These changes increased form 10 G to 30 G, but were not observed when the samples were separated after vibration and turbulence. Conclusions: Whole blood showed little vulnerability to turbulence, whereas plasma samples separated from blood cells by gel may be significantly influenced by turbulence when separated by spinning before the exposure. Centrifugation of plasma samples collected in tubes with separator gel should be avoided before drone flights that could be subject to turbulence.

• Mette Eskild Bornstedt, Nina Gjerlaugsen, Ole Kristoffer Olstad, Jens Petter Berg, May K. Lyamouri Bredahl & Per Medbøe Thorsby (2020). Vitamin D metabolites influence expression of genes concerning cellular viability and function in insulin producing β-cells (INS1E). Gene. ISSN 0378-1119. 746:144649, s. 1–8. doi: 10.1016/j.gene.2020.144649. Fulltekst i vitenarkiv Vis sammendrag

  Background Studies have shown that vitamin D can enhance glucose-stimulated insulin secretion (GSIS) and change the expression of genes in pancreatic β-cells. Still the mechanisms linking vitamin D and GSIS are unknown. Material and methods We used an established β-cell line, INS1E. INS1E cells were pre-treated with 10 nM 1,25(OH)2vitamin D or 10 nM 25(OH)vitamin D for 72 h and stimulated with 22 mM glucose for 60 min. RNA was extracted for gene expression analysis. Results Expression of genes affecting viability, apoptosis and GSIS changed after pre-treatment with both 1,25(OH)2vitamin D and 25(OH)vitamin D in INS1E cells. Stimulation with glucose after pre-treatment of INS1E cells with 1,25(OH)2vitamin D resulted in 181 differentially expressed genes, whereas 526 genes were differentially expressed after pre-treatment with 25(OH)vitamin D. Conclusion Vitamin D metabolites may affect pancreatic β-cells and GSIS through changed gene expression for genes involved in β-cell function and viability.

• Alexander K. Eieland, Kjersti R. Normann, Arvind Y. M. Sundaram, Tuula A. Nyman, Kristin A. B. Øystese & Tove Lekva [Vis alle 9 forfattere av denne artikkelen] (2020). Distinct pattern of endoplasmic reticulum protein processing and extracellular matrix proteins in functioning and silent corticotroph pituitary adenomas. Cancers. 12(10), s. 1–20. doi: 10.3390/cancers12102980. Fulltekst i vitenarkiv Vis sammendrag

  Functioning (FCA) and silent corticotroph (SCA) pituitary adenomas act differently from a clinical perspective, despite both subtypes showing positive TBX19 (TPIT) and/or adrenocorticotropic hormone (ACTH) staining by immunohistochemistry. They are challenging to treat, the former due to functional ACTH production and consequently hypercortisolemia, and the latter due to invasive and recurrent behavior. Moreover, the molecular mechanisms behind their distinct behavior are not clear. We investigated global transcriptome and proteome changes in order to identify signaling pathways that can explain FCA and SCA differences (e.g., hormone production vs. aggressive growth). In the transcriptomic study, cluster analyses of differentially expressed genes revealed two distinct groups in accordance with clinical and histological classification. However, in the proteomic study, a greater degree of heterogeneity within the SCA group was found. Genes and proteins related to protein synthesis and vesicular transport were expressed by both adenoma groups, although different types and a distinct pattern of collagen/extracellular matrix proteins were presented by each group. Moreover, several genes related to endoplasmic reticulum protein processing were overexpressed in the FCA group. Together, our findings shed light on the different repertoires of activated signaling pathways in corticotroph adenomas, namely, the increased protein processing capacity of FCA and a specific pattern of adhesion molecules that may play a role in the aggressiveness of SCA.

• Birgitte Mitlid-Mork, Sophie Bowe, Jon Michael Gran, Nils Bolstad, Jens Petter Berg & Christopher W.G. Redman [Vis alle 8 forfattere av denne artikkelen] (2020). Maternal placental growth factor and soluble fms-like tyrosine kinase-1 reference ranges in post-term pregnancies: A prospective observational study. PLOS ONE. 15:e0240473(10), s. 1–14. doi: 10.1371/journal.pone.0240473. Fulltekst i vitenarkiv Vis sammendrag

  Background Post-term pregnancies have increased risks for adverse fetal and maternal outcomes. Maternal concentrations of the placenta-associated proteins placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) have been identified as predictors for preeclampsia and fetal growth restriction, both syndromes of placental dysfunction. We have proposed that low maternal circulating PlGF and increased sFlt-1 are general markers for syncytiotrophoblast stress, which increases at and beyond term, even in apparently uncomplicated pregnancies. Our aim was to establish circulating PlGF, sFlt-1, and sFlt-1/PlGF reference ranges in healthy post-term pregnancies (gestational week ≥40+2), comparing with healthy term pregnancies and evaluating associations between time to delivery and biomarker percentiles. Methods Of 501 healthy, singleton post-term pregnancies prospectively recruited between September 2016 and December 2017 at our tertiary obstetric department, 426 with an uncomplicated delivery outcome contributed PlGF and sFlt-1 serum concentrations for reference range construction. A retrospective, cross-sectional, term group with an uncomplicated delivery outcome (n = 146) served as comparison. Differences in percentile values between groups and confidence intervals were calculated by quantile regression. Results In post-term pregnancies the 5th, 50th, and 95th percentiles for PlGF were: 70, 172, and 496 pg/mL; for sFlt-1: 2074, 4268, and 9141 pg/mL; and for sFlt-1/PlGF 5.3, 25.5, and 85.2. Quantile regression analyses comparing the post-term to the term group showed for PlGF a trend towards higher 10th through 30th percentiles, for sFlt-1 significantly higher 10th through 80th percentiles, and for sFlt-1/PlGF ratio significantly higher 30th percentile and significantly lower 95th percentile. PlGF below the 5th percentile and sFlt-1/PlGF ratio above the 95th percentile was associated with shorter time to delivery (p = 0.031 and p = 0.025, respectively). Conclusions Our findings support the concept of increasing syncytiotrophoblast stress post-term in clinically healthy pregnancies. Whether post-term dysregulated angiogenic markers reflect a biological placental clock merits further investigation.

• Berit Sletbakk Brusletto, Else Marit Løberg, Bernt C Hellerud, Ingeborg Løstegaard Goverud, Jens Petter Berg & Ole Kristoffer Olstad [Vis alle 9 forfattere av denne artikkelen] (2020). Extensive changes in transcriptomic “fingerprints” and immunological cells in the large organs of patients dying of acute septic shock and multiple organ failure caused by Neisseria meningitidis. Frontiers in Cellular and Infection Microbiology. 10:42, s. 1–30. doi: 10.3389/fcimb.2020.00042. Fulltekst i vitenarkiv Vis sammendrag

  Background: Patients developing meningococcal septic shock reveal levels of Neisseria meningitidis (106-108/mL) and endotoxin (101-103 EU/mL) in the circulation and organs, leading to acute cardiovascular, pulmonary and renal failure, coagulopathy and a high case fatality rate within 24 h. Objective: To investigate transcriptional profiles in heart, lungs, kidneys, liver, and spleen and immunostain key inflammatory cells and proteins in post mortem formalin-fixed, paraffin-embedded (FFPE) tissue samples from meningococcal septic shock patients. Patients and Methods: Total RNA was isolated from FFPE and fresh frozen (FF) tissue samples from five patients and two controls (acute non-infectious death). Differential expression of genes was detected using Affymetrix microarray analysis. Lung and heart tissue samples were immunostained for T-and B cells, macrophages, neutrophils and the inflammatory markers PAI-1 and MCP-1. Inflammatory mediators were quantified in lysates from FF tissues. Results: The transcriptional profiles showed a complex pattern of protein-coding and non-coding RNAs with significant regulation of pathways associated with organismal death, cell death and survival, leukocyte migration, cellular movement, proliferation of cells, cell-to-cell signaling, immune cell trafficking, and inflammatory responses in an organ-specific clustering manner. The canonical pathways including acute phase response-, EIF2-, TREM1-, IL-6-, HMBG1-, PPAR signaling, and LXR/RXR activation were associated with acute heart, pulmonary, and renal failure. Fewer genes were regulated in the liver and particularly in the spleen. The main upstream regulators were TNF, IL-1β, IL-6, RICTOR, miR-6739-3p, and CD3. Increased numbers of inflammatory cells (CD68+, MPO+, CD3+, and CD20+) were found in lungs and heart. PAI-1 inhibiting fibrinolysis and MCP-1 attracting leukocyte were found significantly present in the septic tissue samples compared to the controls. Conclusions: FFPE tissue samples can be suitable for gene expression studies as well as immunostaining of specific cells or molecules. The most pronounced gene expression patterns were found in the organs with highest levels of Neisseria meningitidis DNA. Thousands of protein-coding and non-coding RNA transcripts were altered in lungs, heart and kidneys. We identified specific biomarker panels both protein-coding and non-coding RNA transcripts, which differed from organ to organ. Involvement of many genes and pathways add up and the combined effect induce organ failure.

• Prudence Atukunda, Grace Kyamazima Mehangye Muhoozi, Lien My Diep, Jens Petter Berg, Ane Cecilie Westerberg & Per Ole Iversen (2020). The association of urine markers of iodine intake with development and growth among children in rural Uganda: A secondary analysis of a randomised education trial. Public Health Nutrition (PHN). ISSN 1368-9800. s. 1–10. doi: 10.1017/S1368980020001603. Fulltekst i vitenarkiv Vis sammendrag

  Objective: We examined associations of urine iodide excretion, proxy for iodine intake, with child development and growth. Design: This is a secondary analysis of a 1:1 cluster-randomised trial with a 6-month nutrition/stimulation/hygiene education intervention among mothers of children aged 6–8 months to improve child development and growth. Development was assessed using Bayley Scales of Infant and Toddler Development–III (BSID-III) and Ages and Stages Questionnaire (ASQ), whereas anthropometry was used to assess growth. Urine iodide concentration (UIC) and urine iodide/creatinine ratio (ICR) were measured. Setting: The current study was conducted in southern Uganda. Participants: We randomly selected 155 children from the 511 enrolled into the original trial and analysed data when they were aged 20–24 and 36 months. Results: Median UIC for both study groups at 20–24 and 36 months were similar (P > 0·05) and within the normal range of 100–199 µg/l (0·79–1·60 µmol/l), whereas the intervention group had significantly higher ICR at 20–24 months. The BSID-III cognitive score was positively associated (P = 0·028) with ICR at 20–24 months in the intervention group. The ASQ gross motor score was negatively associated (P = 0·020) with ICR at 20–24 months among the controls. ICR was not significantly associated with anthropometry in the two study groups at either time-point. Conclusions: Following the intervention, a positive association was noted between ICR and child’s cognitive score at 20–24 months, whereas no positive association with ICR and growth was detected. Iodine sufficiency may be important for child’s cognitive development in this setting.

• Sigrid Beitland, Espen Rostrup Nakstad, Jens Petter Berg, Anne-Marie Siebke, Berit Sletbakk Brusletto & Cathrine Brunborg [Vis alle 8 forfattere av denne artikkelen] (2019). Urine β-2-Microglobulin, Osteopontin, and Trefoil Factor 3 May Early Predict Acute Kidney Injury and Outcome after Cardiac Arrest. Critical Care Research and Practice. ISSN 2090-1305. 2019. doi: 10.1155/2019/4384796. Fulltekst i vitenarkiv Vis sammendrag

  Purpose. Acute kidney injury (AKI) is a common complication after out-of-hospital cardiac arrest (OHCA), leading to increased mortality and challenging prognostication. Our aim was to examine if urine biomarkers could early predict postarrest AKI and patient outcome. Methods. A prospective observational study of resuscitated, comatose OHCA patients admitted to Oslo University Hospital in Norway. Urine samples were collected at admission and day three postarrest and analysed for β-2-microglobulin (β2M), osteopontin, and trefoil factor 3 (TFF3). Outcome variables were AKI within three days according to the Kidney Disease Improving Global Outcome criteria, in addition to six-month mortality and poor neurological outcome (PNO) (cerebral performance category 3–5). Results. Among 195 included patients (85% males, mean age 60 years), 88 (45%) developed AKI, 88 (45%) died, and 96 (49%) had PNO. In univariate analyses, increased urine β2M, osteopontin, and TFF3 levels sampled at admission and day three were independent risk factors for AKI, mortality, and PNO. Exceptions were that β2M measured at day three did not predict any of the outcomes, and TFF3 at admission did not predict AKI. In multivariate analyses, combining clinical parameters and biomarker levels, the area under the receiver operating characteristics curves (95% CI) were 0.729 (0.658–0.800), 0.797 (0.733–0.861), and 0.812 (CI 0.750–0.874) for AKI, mortality, and PNO, respectively. Conclusions. Urine levels of β2M, osteopontin, and TFF3 at admission and day three were associated with increased risk for AKI, mortality, and PNO in comatose OHCA patients. This trail is registered with NCT01239420.

• Marthe-Lise Næss-Andresen, Åse Ruth Eggemoen, Jens Petter Berg, Ragnhild Sørum Falk & Anne Karen Jenum (2019). Serum ferritin, soluble transferrin receptor, and total body iron for the detection of iron deficiency in early pregnancy: A multiethnic population-based study with low use of iron supplements. American Journal of Clinical Nutrition. ISSN 0002-9165. 109(3), s. 566–575. doi: 10.1093/ajcn/nqy366. Fulltekst i vitenarkiv Vis sammendrag

  Which blood-based indicator best reflects the iron status in pregnant women is unclear. Better assessments of iron status in today's multiethnic populations are needed to optimize treatment and clinical recommendations.We aimed to determine the prevalence of anemia (hemoglobin &lt;11.0 g/dL in first and &lt;10.5 g/dL in second trimester) and iron deficiency (ID) by the iron indicators serum ferritin &lt;15 µg/L, serum soluble transferrin receptor (sTfR) &gt;4.4 mg/L, and calculated total body iron &lt;0 mg/kg, and their associations with ethnicity.This was a population-based cross-sectional study from primary antenatal care of 792 healthy women in early pregnancy in Oslo, Norway. We categorized the women into 6 ethnic groups: Western European, South Asian, Middle Eastern, Sub-Saharan African, East Asian, and Eastern European.Anemia was found in 5.9% of women (Western Europeans: 1.8%; non-Western: 0–14%, P &lt; 0.05). ID from ferritin was found in 33% (Western Europeans: 15%; non-Western: 27–55%, P &lt; 0.05). ID from sTfR was found in 6.5% (Western Europeans: 0.3%; non-Western: 0–20%, P &lt; 0.01). Calculated total body iron indicated ID in 11% (Western Europeans: 0.6%, non-Western: 7.0–28%, P &lt; 0.01). The prevalence of ID was significantly higher by all measures in South Asian, Sub-Saharan African, and Middle Eastern than in Western European women, and the ethnic differences persisted after adjusting for confounders. South Asians, Sub-Saharan Africans, and Middle Easterners had lower iron concentrations by all measures for all hemoglobin intervals. Anemia related to ID varied from 35% (sTfR) to 46% (total body iron) and 72% (ferritin) depending on the iron indicator used.Women at the highest risk of ID and anemia were of South Asian, Middle Eastern, and Sub-Saharan African origin. The prevalence of ID differed considerably depending on the iron indicator used.

• Aina Jansen, Jens Petter Berg, Ole Klungsøyr, Mette Helen Bjørge Müller, Jan Ludvig Lyche & Jan Aaseth (2019). The Influence of Persistent Organic Pollutants on Thyroidal, Reproductive and Adrenal Hormones After Bariatric Surgery. Obesity Surgery. ISSN 0960-8923. doi: 10.1007/s11695-019-04273-w. Fulltekst i vitenarkiv Vis sammendrag

  Persistent organic pollutants (POPs) including organochlorine pesticides, polychlorinated biphenyls (PCBs), and per- and polyfluoroalkylated substances (PFASs) are suspected endocrine disruptors. AIM: To evaluate the associations between POPs and thyroidal, reproductive, and adrenal hormones in a study population treated with bariatric surgery. METHODS: Blood samples from a cohort of 63 participants before and 1 year after bariatric surgery were analyzed for 16 lipophilic POPs, 17 PFASs, and thyroidal, reproductive, and adrenal hormones. Participants reporting relevant medical conditions or interfering medication were excluded, and plausible confounders were corrected for in multiple regression analyses. RESULTS: Free thyroxine (fT4) showed a significant decrease from preoperative to postoperative follow-up, and regression analyses demonstrated that p,p'-dichlorodiphenyldichloroethylene (p,p-DDE) was inversely associated with the ratio free triiodothyronine/free thyroxine (fT3/fT4). Testosterone concentrations in male participants increased significantly in the study period, and sex hormone-binding globulin (SHBG) increased in both gender. Regression analyses showed positive associations between increased levels of lipophilic POPs and the raised postoperative testosterone and SHBG concentrations in males. For females, an inverse association between the sum perfluoroalkyl carboxylic acids (ΣPFCA) and SHBG was seen. Regression analyses of postoperative serum cortisol concentrations on changes in hexachlorobenzene (HCB) showed a non-significant inverse association. CONCLUSION: The results suggest that POPs may have an influence on the hypothalamic-pituitary-thyroid (HPT) and the hypothalamic-pituitary-gonadal (HPG) axes after bariatric surgery. Because of small sample sizes and discrepancy in the sampling time points pre- and postoperatively, the observed hormonal impacts of POPs must be interpreted as associative and not causative. Further studies are needed to confirm the findings.

• Unni Gopinathan, Kathrine Redalen, Anne-Marie Siebke, Peter Kierulf, Petter Brandtzæg & Anne Hansen Ree [Vis alle 8 forfattere av denne artikkelen] (2018). Large-scale reduction of tyrosine kinase activities in human monocytes stimulated in vitro with N. meningitidis. PLOS ONE. 13(1). doi: 10.1371/journal.pone.0181912. Fulltekst i vitenarkiv Vis sammendrag

  N. meningitidis induces extensive gene expression changes in human monocytes, suggesting that complex networks of signaling pathways are activated during meningococcal sepsis. These effects are modulated by the anti-inflammatory cytokine interleukin-10 (IL-10). To further study changes in signal transduction suggested by mRNA data, we used kinase substrate arrays to identify composite kinase activities induced by lysates from a primary human monocyte model system. Cell lysates were prepared from monocytes treated with the following experimental conditions: 106 N. meningitidis/mL, 25 ng/mL IL-10, 106 N. meningitidis/mL in combination with 25 ng/mL IL-10, and vehicle. Lysates were subjected to kinase activity profiling with Tyrosine Kinase PamChip® arrays containing 144 kinase peptide substrates. In our experimental model, we were not able to detect a statistically significant large-scale change in ex vivo array peptide phosphorylation by lysates from monocytes treated for 15 minutes. Targets of the IL-10 anti-inflammatory response were not identified. A profound inhibition of array peptide phosphorylation by monocytes treated for 60 minutes was identified, suggesting low activity of a large number of kinases associated with different signaling pathways and immune cell functions, including STAT3 activity, Nf-κB and VEGF signaling, and PTEN signaling activity. The peptide representing ZBTB16, which was reduced in phosphorylation by lysates from all three experimental conditions, was in Ingenuity Pathway Analysis identified to be linked to reduced cytokine release and mRNA levels of tumor necrosis factor (TNF), IL-6, and CXCL10. Further studies should investigate changes in tyrosine kinase-mediated signal transduction in human immune cells, in order to evaluate the potential clinical application of kinome profiling in the study of systemic inflammatory responses to pathogens.

• Kristin Astrid Berland Øystese, Jens Petter Berg, Kjersti Ringvoll Normann, Manuela Zucknick, Olivera Casar-Borota & Jens Bollerslev (2018). The role of E and N-cadherin in the postoperative course of gonadotroph pituitary tumours. Endocrine. ISSN 1355-008X. 62(2), s. 351–360. doi: 10.1007/s12020-018-1679-0. Fulltekst i vitenarkiv
• Bjørnar Hassel, Espen Mariussen, Ane-Victoria Idland, Gry Torsæter Dahl, Johan Ræder & Frede Jon Frihagen [Vis alle 10 forfattere av denne artikkelen] (2018). CSF sodium at toxic levels precedes delirium in hip fracture patients. Neurotoxicology. ISSN 0161-813X. 69(December), s. 11–16. doi: 10.1016/j.neuro.2018.08.010. Fulltekst i vitenarkiv
• Lara Pasovic, Tor Paaske Utheim, Sjur Reppe, Ayyad Ahmad Zartasht Khan, Catherine Jackson & Bernd Thiede [Vis alle 9 forfattere av denne artikkelen] (2018). Improvement of storage medium for cultured human retinal pigment epithelial cells using factorial design. Scientific Reports. 8(1). doi: 10.1038/s41598-018-24121-8. Fulltekst i vitenarkiv Vis sammendrag

  Storage of human retinal pigment epithelium (hRPE) can contribute to the advancement of cell-based RPE replacement therapies. The present study aimed to improve the quality of stored hRPE cultures by identifying storage medium additives that, alone or in combination, contribute to enhancing cell viability while preserving morphology and phenotype. hRPE cells were cultured in the presence of the silk protein sericin until pigmentation. Cells were then stored for 10 days in storage medium plus sericin and either one of 46 diferent additives. Individual efects of each additive on cell viability were assessed using epifuorescence microscopy. Factorial design identifed promising additive combinations by extrapolating their individual efects. Supplementing the storage medium with sericin combined with adenosine, L-ascorbic acid and allopurinol resulted in the highest cell viability (98.6 ± 0.5%) after storage for three days, as measured by epifuorescence microscopy. Flow cytometry validated the fndings. Proteomics identifed 61 upregulated and 65 downregulated proteins in this storage group compared to the unstored control. Transmission electron microscopy demonstrated the presence of melanosomes after storage in the optimized medium. We conclude that the combination of adenosine, L-ascorbic acid, allopurinol and sericin in minimal essential medium preserves RPE pigmentation while maintaining cell viability during storage.

• Hans Christian Dalsbotten Aass, Marit Synnøve Hellum, Anne-Marie Siebke, Petter Brandtzæg, Jens Petter Berg & Reidun Øvstebø [Vis alle 7 forfattere av denne artikkelen] (2018). Whole-blood incubation with the Neisseria meningitidis lpxL1 mutant induces less pro-inflammatory cytokines than the wild type, and IL-10 reduces the MyD88-dependent cytokines. Innate Immunity. ISSN 1753-4259. 24(2), s. 101–111. doi: 10.1177/1753425917749299. Fulltekst i vitenarkiv Vis sammendrag

  Levels of bacterial LPS, pro-inflammatory cytokines and IL-10 are related to the severity of meningococcal septicaemia. Patients infected with a Neisseria meninigitidis lpxL1 mutant (Nm-mutant) with penta-acylated lipid A present with a milder meningococcal disease than those infected with hexa-acylated Nm wild type (Nm-wt). The aim was to compare the pro-inflammatory responses after ex vivo incubation with the heat-inactivated Nm-wt or the Nm-mutant in citrated whole blood, and the modulating effects of IL-10. Concomitantly, we measured intracellular IL-6, IL-8 and TNF-α to elucidate which cell types were responsible for the pro-inflammatory responses. Incubation with Nm-wt (106/ml;107/ml;108/ml) resulted in a dose-dependent increase of the MyD88-dependent pro-inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α), which were mainly derived from monocytes. In comparison, only 108/ml of the Nm-mutant significantly increased the concentration of these cytokines. The MyD88-independent cytokines (IP-10, RANTES) were evidently increased after incubation with the Nm-wt but were unaffected by the Nm-mutant. Co-incubation with IL-10 significantly reduced the concentrations of the MyD88-dependent cytokines induced by both the Nm-wt and the Nm-mutant, whereas the MyD88-independent cytokines were almost unaffected. In summary, the Nm-mutant is a weaker inducer of the MyD88-dependent/independent cytokines than the Nm-wt in whole blood, and IL-10 attenuates the Nm-stimulated increase in MyD88-dependent pro-inflammatory cytokines.

• Marit Synnøve Hellum, Anne-Marie Siebke, Jens Petter Berg, Petter Brandtzæg, Reidun Øvstebø & Carola Henriksson (2017). The Neisseria meningitidis lpxL1 mutant induces less tissue factor expression and activity in primary human monocytes and monocyte-derived microvesicles than the wild type meningococcus. Innate Immunity. ISSN 1753-4259. 23(2), s. 196–205. doi: 10.1177/1753425916684201. Fulltekst i vitenarkiv
• Kristin Astrid Berland Øystese, Olivera Casar-Borota, Kjersti Ringvoll Normann, Manuela Zucknick, Jens Petter Berg & Jens Bollerslev (2017). Estrogen Receptor α, a Sex-Dependent Predictor of Aggressiveness in Nonfunctioning Pituitary Adenomas: SSTR and Sex Hormone Receptor Distribution in NFPA. Journal of Clinical Endocrinology and Metabolism (JCEM). ISSN 0021-972X. 102(9), s. 3581–3590. doi: 10.1210/jc.2017-00792. Fulltekst i vitenarkiv
• Maria Vistnes, German Tapia, Karl Staffan Mårild, Øivind Midttun, Per Magne Ueland & Marte K Viken [Vis alle 14 forfattere av denne artikkelen] (2017). Plasma immunological markers in pregnancy and cord blood: A possible link between macrophage chemo-attractants and risk of childhood type 1 diabetes. American journal of reproductive immunology. ISSN 1046-7408. 79(3). doi: 10.1111/aji.12802. Fulltekst i vitenarkiv
• Unni Gopinathan, Reidun Øvstebø, Berit Sletbakk Brusletto, Ole Kristoffer Olstad, Peter Kierulf & Petter Brandtzæg [Vis alle 7 forfattere av denne artikkelen] (2017). Transcriptomic data from two primary cell models stimulating human monocytes suggest inhibition of oxidative phosphorylation and mitochondrial function by N. meningitidis which is partially up-regulated by IL-10. BMC Immunology. 18:46, s. 1–17. doi: 10.1186/s12865-017-0229-5. Fulltekst i vitenarkiv Vis sammendrag

  Background Biological interpretation of DNA microarray data may differ depending on underlying assumptions and statistical tests of bioinformatics tools used. We used Gene Set Enrichment Analysis (GSEA) and Ingenuity Pathway Analysis (IPA) to analyze previously generated DNA microarray data from human monocytes stimulated with N. meningitidis and IL-10 (“the model system”), and with meningococcal sepsis plasma before and after immunodepletion of IL-10 (“the patient plasma system”). The objectives were to compare if the two bioinformatics methods resulted in similar biological interpretation of the datasets, and to identify whether GSEA provided additional insight compared with IPA about the monocyte host response to meningococcal activation. Results In both experimental models, GSEA and IPA identified genes associated with pro-inflammatory innate immune activation, including TNF-signaling, Toll-like receptor signaling, JAK-STAT-signaling, and type I and type II interferon signaling. GSEA identified genes regulated by the presence of IL-10 with similar gene sets in both the model system and the patient plasma system. In the model system, GSEA and IPA in sum identified 170 genes associated with oxidative phosphorylation/mitochondrial function to be down-regulated in monocytes stimulated with meningococci. In the patient plasma system, GSEA and IPA in sum identified 122 genes associated with oxidative phosphorylation/mitochondrial dysfunction to be down-regulated by meningococcal sepsis plasma depleted for IL-10. Using IPA, we identified IL-10 to up-regulate 18 genes associated with oxidative phosphorylation/mitochondrial function that were down-regulated by N. meningitidis. Conclusions Biological processes associated with the gene expression changes in the model system of meningococcal sepsis were comparable with the results found in the patient plasma system. By combining GSEA with IPA, we discovered an inhibitory effect of N. meningitidis on genes associated with mitochondrial function and oxidative phosphorylation, and that IL-10 partially reverses this strong inhibitory effect, thereby identifying, to our knowledge, yet another group of genes where IL-10 regulates the effect of LPS. We suggest that relying on a single bioinformatics tool together with an arbitrarily chosen filtering criteria for data analysis may result in overlooking relevant biological processes and signaling pathways associated with genes differentially expressed between compared experimental conditions.

• Christin Waage, Anne Karen Jenum, Ibrahimu Mdala, Jens Petter Berg, Kåre Rønn Richardsen & Kåre I. Birkeland (2017). Associations between gestational diabetes mellitus and elevated HbA1c early postpartum in a multi-ethnic population. Primary Care Diabetes. ISSN 1751-9918. 11(2), s. 132–139. doi: 10.1016/j.pcd.2016.09.007. Fulltekst i vitenarkiv Vis sammendrag

  Aims To investigate the prevalence of elevated HbA1c 14 weeks postpartum in different ethnic groups and in women with and without gestational diabetes mellitus (GDM) in the index pregnancy and to explore demographic and biological factors from early pregnancy associated with elevated HbA1c (HbA1c ≥5.7% (≥39 mmol/mol)) postpartum. Methods From a cohort study in Oslo, Norway, we included 570 pregnant women, examined in gestational week 15, 28, and 14 weeks postpartum. The association between elevated HbA1c and demographic and biological factors were assessed by logistic regression analyses. Results The prevalence of elevated HbA1c postpartum was 23% in the total population, 15% among Western Europeans and 28% among women with ethnic minority background (p < 0.01). In ethnic minorities elevated HbA1c was found in 39% of women with recent GDM diagnosed by the World Health Organization 2013 criteria and in 21% of women without GDM (p < 0.01), compared to 22% and 13% in Western Europeans (p = 0.11). We found independent associations between elevated HbA1c and ethnic minority background (OR 2.0, 95% CI 1.27, 3.18), and GDM (OR 2.04, 95% CI 1.35, 3.10) (p < 0.01). Conclusions The prevalence of elevated HbA1c postpartum was 23%, and significantly higher among women with ethnic minority background irrespective of GDM.

• Benedicte Marie Jørgenrud, Lars Christian Stene, German Tapia, Håkon Bøås, Milaim Pepaj & Jens Petter Berg [Vis alle 10 forfattere av denne artikkelen] (2017). Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study. Pediatric Diabetes. ISSN 1399-543X. 18, s. 111–119. doi: 10.1111/pedi.12360. Fulltekst i vitenarkiv Vis sammendrag

  Aims The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Method Up to four longitudinal plasma samples from age 3 months from case children who developed islet autoimmunity (n = 29) and autoantibody-negative control children (n = 29) with the HLA DR4-DQ8/DR3-DQ2 genotype were analyzed using two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer for detection of small polar metabolites. Results Plasma metabolite levels were found to depend strongly on age, with fold changes varying up to 50% from age 3 to 24 months (p < 0.001 after correction for multiple testing). Tyrosine levels tended to be lower in case children, but this was not significant after correction for multiple testing. Ornithine levels were lower in case children compared with the controls at the time of seroconversion, but the difference was not statistically significant after correcting for multiple testing. Breastfeeding for at least 3 months as compared with shorter duration was associated with higher plasma levels of isoleucine, and lower levels of methionine and 3,4-dihydroxybutyric acid at 3 months of age. Conclusions Plasma levels of several small, polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid.

• Olav Klingenberg, Torill Furuset, Camilla Røising Hestbråten, Marit Hansen Hallberg, Astrid Steiro & Iren Røstbakken Orset [Vis alle 7 forfattere av denne artikkelen] (2017). HbA1c analysis by capillary electrophoresis?comparison with chromatography and an immunological method. Scandinavian Journal of Clinical and Laboratory Investigation. ISSN 0036-5513. 77(6), s. 458–464. doi: 10.1080/00365513.2017.1338747. Fulltekst i vitenarkiv Vis sammendrag

  Background: Haemoglobin A1c (HbA1c) has become an even more important analyte for clinical laboratories during recent years with the introduction of its diagnostic use for diabetes mellitus. Several different analytical principles can be used, each with their advantages and disadvantages. Aim: We wanted to compare Sebia Capillarys 2 Flex Piercing (Capillarys) with our routine HbA1c methods, which were an HPLC method (Tosoh G7) and an immunoassay (Tina-Quant on Roche Modular P) by analysing a large clinical material. Furthermore, we investigated sample stability. Methods: HbA1c analysis was performed in parallel by all three methods for more than 600 patient samples including common and some rare haemoglobin variants, as well as for several controls, some with set target values. Sample stability at room temperature and refrigerated was assessed for up to seven days. Results: Capillarys produced generally somewhat lower HbA1c values than both comparison methods, apparently due to positive bias for the comparison methods. Leaving out samples with haemoglobin variants, we found a mean bias (95% CI) for Capillarys compared to Tosoh G7 (without factorization) and Modular of −0.39 (−0.40 to −0.38) and −0.16 (−0.17 to −0.14) % HbA1c, respectively. HbA1c results were similar between instruments for samples from dialysis patients and for samples with heterozygous common haemoglobin variants, except that Tosoh G7 reported too low results in the presence of Hb E. For heterozygous Hb Raleigh, Capillarys and the immunoassay gave similar results. Conclusion: Capillarys is a convenient instrument for routine HbA1c analysis. © 2017 Taylor & Francis

• Berit Sletbakk Brusletto, Bernt C Hellerud, Else Marit Løberg, Ingeborg Løstegaard Goverud, Åshild Vege & Jens Petter Berg [Vis alle 8 forfattere av denne artikkelen] (2017). Traceability and distribution of Neisseria meningitidis DNA in archived post mortem tissue samples from patients with systemic meningococcal disease. BMC Clinical Pathology. 17(1). doi: 10.1186/s12907-017-0049-9. Fulltekst i vitenarkiv Vis sammendrag

  Background The pathophysiology and outcome of meningococcal septic shock is closely associated with the plasma level of N. meningitidis lipopolysaccharides (LPS, endotoxin) and the circulating level of meningococcal DNA. The aim of the present study was to quantify the number of N. meningitidis in different formalin-fixed, paraffin-embedded (FFPE) tissue samples and fresh frozen (FF) tissue samples from patients with systemic meningococcal disease (SMD), to explore the distribution of N. meningitidis in the body. Methods DNA in FFPE and FF tissue samples from heart, lungs, liver, kidneys, spleen and brain from patients with meningococcal shock and controls (lethal pneumococcal infection) stored at variable times, were isolated. The bacterial load of N. meningitidis DNA was analyzed using quantitative real-time PCR (qPCR) and primers for the capsule transport A (ctrA) gene (1 copy per N. meningitidis DNA). The human beta-hemoglobin (HBB) gene was quantified to evaluate effect of the storage times (2-28 years) and storage method in archived tissue. Results N. meningitidis DNA was detected in FFPE and FF tissue samples from heart, lung, liver, kidney, and spleen in all patients with severe shock. In FFPE brain, N. meningitidis DNA was only detected in the patient with the highest concentration of LPS in the blood at admission to hospital. The highest levels of N. meningitidis DNA were found in heart tissue (median value 3.6 × 107 copies N. meningitidis DNA/μg human DNA) and lung tissue (median value 3.1 × 107 copies N. meningitidis DNA/μg human DNA) in all five patients. N. meningitidis DNA was not detectable in any of the tissue samples from two patients with clinical meningitis and the controls (pneumococcal infection). The quantity of HBB declined over time in FFPE tissue stored at room temperature, suggesting degradation of DNA. Conclusions High levels of N. meningitidis DNA were detected in the different tissue samples from meningococcal shock patients, particularly in the heart and lungs suggesting seeding and major proliferation of meningococci in these organs during the development of shock, probably contributing to the multiple organ failure. The age of archived tissue samples appear to have an impact on the amount of quantifiable N. meningitidis DNA.

• Sigrid Beitland, Bård Endre Waldum-Grevbo, Espen Rostrup Nakstad, Jens Petter Berg, Anne-Marie Siebke & Berit Sletbakk Brusletto [Vis alle 9 forfattere av denne artikkelen] (2016). Urine biomarkers give early prediction of acute kidney injury and outcome after outof- hospital cardiac arrest. Critical Care. ISSN 1364-8535. 20(1). doi: 10.1186/s13054-016-1503-2. Fulltekst i vitenarkiv Vis sammendrag

  Background Post-resuscitation care after out-of-hospital cardiac arrest (OHCA) is challenging due to the threat of organ failure and difficult prognostication. Our aim was to examine whether urine biomarkers could give an early prediction of acute kidney injury (AKI) and outcome. Methods This was a prospective observational study of comatose OHCA patients at Oslo University Hospital Ullevål, Norway. Risk factors were clinical parameters and biomarkers measured in spot urine (cystatin C, neutrophil gelatinase-associated lipocalin (NGAL) and the product of tissue inhibitor of metalloproteinase 2 (TIMP-2) and insulin-like growth factor-binding protein 7 (IGFBP7)) at admission and day 3. Outcome variables were AKI within 3 days using the Kidney Disease Improving Global Outcomes definition, 6-month mortality, and poor neurological outcome (PNO) defined as cerebral performance category 3–5. Results Among 195 included patients (85 % males, mean age 60 years), 88 (45 %) died, 96 (49 %) had PNO, and 88 (45 %) developed AKI. In univariate analysis, increased urine cystatin C and NGAL concentration sampled at admission and day 3 were independent risk factors for AKI, mortality and PNO. Increased urine TIMP-2 × IGFBP7 levels was associated with AKI only at admission. In multivariate analyses combining clinical parameters and biomarker concentrations, the area under the receiver operating characteristics curve (AuROC) with 95 % confidence interval (CI) were 0.774 (0.700–0.848), 0.812 (0.751–0.873), and 0.819 (0.759–0.878) for AKI, mortality and PNO, respectively. Conclusions In comatose OHCA patients, urine levels of cystatin C and NGAL at admission and day 3 were independent risk factors for AKI, 6-month mortality and PNO. Trial registration Clinicaltrials.gov NCT01239420 . Registered 10 November 2010.

• Karen Roksund Hov, Jens Petter Berg, Frede Jon Frihagen, Johan Ræder, Roanna J. Hall & Torgeir Bruun Wyller [Vis alle 7 forfattere av denne artikkelen] (2016). Blood-cerebrospinal fluid barrier integrity in delirium determined by Q-Albumin. Dementia and Geriatric Cognitive Disorders. ISSN 1420-8008. 41(3-4), s. 192–198. doi: 10.1159/000443789. Fulltekst i vitenarkiv
• Kjersti Ringvoll Normann, Kristin Astrid Berland Øystese, Jens Petter Berg, Tove Lekva, Jon Berg-Johnsen & Jens Bollerslev [Vis alle 7 forfattere av denne artikkelen] (2016). Selection and validation of reliable reference genes for RT-qPCR analysis in a large cohort of pituitary adenomas. Molecular and Cellular Endocrinology. ISSN 0303-7207. 437, s. 183–189. doi: 10.1016/j.mce.2016.08.030. Fulltekst i vitenarkiv
• Daniel Sachse, Anne Lee Solevåg, Jens Petter Berg & Britt Nakstad (2016). The role of plasma and urine metabolomics in identifying new biomarkers in severe newborn asphyxia: A study of asphyxiated newborn pigs following cardiopulmonary resuscitation. PLOS ONE. 11:e0161123(8). doi: 10.1371/journal.pone.0161123. Fulltekst i vitenarkiv Vis sammendrag

  Background Optimizing resuscitation is important to prevent morbidity and mortality from perinatal asphyxia. The metabolism of cells and tissues is severely disturbed during asphyxia and resuscitation, and metabolomic analyses provide a snapshot of many small molecular weight metabolites in body fluids or tissues. In this study metabolomics profiles were studied in newborn pigs that were asphyxiated and resuscitated using different protocols to identify biomarkers for subject characterization, intervention effects and possibly prognosis. Methods A total of 125 newborn Noroc pigs were anesthetized, mechanically ventilated and inflicted progressive asphyxia until asystole. Pigs were randomized to resuscitation with a FiO2 0.21 or 1.0, different duration of ventilation before initiation of chest compressions (CC), and different CC to ventilation ratios. Plasma and urine samples were obtained at baseline, and 2 h and 4 h after return of spontaneous circulation (ROSC, heart rate > = 100 bpm). Metabolomics profiles of the samples were analyzed by nuclear magnetic resonance spectroscopy. Results Plasma and urine showed severe metabolic alterations consistent with hypoxia and acidosis 2 h and 4 h after ROSC. Baseline plasma hypoxanthine and lipoprotein concentrations were inversely correlated to the duration of hypoxia sustained before asystole occurred, but there was no evidence for a differential metabolic response to the different resuscitation protocols or in terms of survival. Conclusions Metabolic profiles of asphyxiated newborn pigs showed severe metabolic alterations. Consistent with previously published reports, we found no evidence of differences between established and alternative resuscitation protocols. Lactate and pyruvate may have a prognostic value, but have to be independently confirmed.

• Gunn Berit Berge Kristensen, Pål Rustad, Jens Petter Berg & Kristin Aakre (2016). Analytical bias exceeding desirable quality goal in 4 out of 5 common immunoassays: Results of a native single serum sample external quality assessment program for cobalamin, folate, ferritin, thyroid-stimulating hormone, and free t4 analyses. Clinical Chemistry. ISSN 0009-9147. 62(9), s. 1255–1263. doi: 10.1373/clinchem.2016.258962. Fulltekst i vitenarkiv
• Marianne K. Kringen, Camilla Stormo, Jens Petter Berg, Sharon F. Terry, Christine M. Vocke & Samar Rizvi [Vis alle 8 forfattere av denne artikkelen] (2015). Copy number variation in the ATP-binding cassette transporter ABCC6 gene and ABCC6 pseudogenes in patients with pseudoxanthoma elasticum. Molecular Genetics & Genomic Medicine. ISSN 2324-9269. 3(3), s. 233–237. doi: 10.1002/mgg3.137. Fulltekst i vitenarkiv Vis sammendrag

  Single mutations in the ATP-binding cassette transporter (ABCC6) gene (OMIM 603234) are known to cause the rare autosomal recessive disease pseudoxanthoma elasticum (PXE). Recently, we have found that copy number variations (CNVs) in pseudogenes of the ABCC6 gene are quite common. The aim of this study was to investigate the frequency and possible contribution of CNV in ABCC6 and its pseudogenes in PXE. Genomic DNA from 212 PXE individuals were examined for copy number by pyrosequencing and quantitative polymerase chain reaction (PCR) and compared with healthy individuals. The frequency of PXE individuals with any CNV was higher than in healthy individuals. The majority of variation comprised known and possibly new deletions in the ABCC6 gene and duplications of the ABCC6P1 and ABCC6P2 genes. ABCC6 deletions and ABCC6P2 duplications were not observed in 142 healthy individuals. In conclusion, by pyrosequencing and quantitative PCR, we were able to detect known and possibly new deletions in the ABCC6 gene that may have caused the PXE phenotype. Pyrosequencing may be used in PXE patients who have obtained incomplete genotype from conventional techniques. The frequency of ABCC6P2 pseudogene duplication was more common in PXE patients than healthy individuals and may affect the PXE phenotype.

• Nils Inge Landrø, Rune Jonassen, Luke Clark, Kari Bente Foss, Martin Aker & Ragnhild Bø [Vis alle 9 forfattere av denne artikkelen] (2015). Serotonin transporter polymorphisms predict response inhibition in healthy volunteers. Neuroscience Letters. ISSN 0304-3940. 584, s. 109–112. doi: 10.1016/j.neulet.2014.10.006. Fulltekst i vitenarkiv
• Sjur Reppe, Agate Noer, Runa Marie Grimholt, Bjarni V Halldorsson, Carolina Medina-Gomez & Vigdis Teig Gautvik [Vis alle 16 forfattere av denne artikkelen] (2015). Methylation of bone SOST, its mRNA, and serum sclerostin levels correlate strongly with fracture risk in postmenopausal women. Journal of Bone and Mineral Research. ISSN 0884-0431. 30(2), s. 249–256. doi: 10.1002/jbmr.2342. Fulltekst i vitenarkiv
• Tove Lekva, Jens Petter Berg, Robert Lyle, Ansgar Heck, Jens Bollerslev & Thor Ueland (2015). Alternative splicing of placental lactogen (CSH2) in somatotroph pituitary adenomas. Neuro - endocrinology letters. ISSN 0172-780X. 36(2), s. 136–142. Fulltekst i vitenarkiv Vis sammendrag

  OBJECTIVES: Somatotroph adenomas secrete supraphysiological amounts of GH, causing acromegaly. We have previously shown epithelial splicing regulator 1 (ESRP1) to play a role in epithelial mesenchymal transition (EMT) progression in these adenomas and account for poor treatment response. We evaluated if the mRNA levels of the GH/CSH gene cluster in somatotroph adenomas are associated with an epithelial phenotype and response to SA treatment. METHODS: We investigated the associations between ESRP1 and the growth hormone/chorionic somatomammotropin (GH/CSH) gene cluster by RNA sequencing (RNAseq). CSH2 isoform 3 mRNA was further evaluated in 65 somatotroph adenomas and associations with disease severity and treatment response. RESULTS: mRNA for all genes in the GH/CSH cluster were expressed, however, only chorionic somatomammotropin 2/placental lactogen 2 (CSH2) displayed an alternative splicing pattern. CSH2 isoform 3 was associated with a dense granulation pattern and an epithelial phenotype with high levels of ESRP1 and E-cadherin expression. Further, CSH2 isoform 3 was associated with reduced serum GH and IGF-I levels after somatostatin analog treatment. CONCLUSIONS: Attenuated CSH2 isoform 3 was associated with mesenchymal phenotype and a blunted clinical response to somatostatin analog treatment in patients with acromegaly.

• Unni Gopinathan, Berit Sletbakk Brusletto, Ole Kristoffer Olstad, Peter Kierulf, Jens Petter Berg & Petter Brandtzæg [Vis alle 7 forfattere av denne artikkelen] (2015). IL-10 immunodepletion from meningococcal sepsis plasma induces extensive changes in gene expression and cytokine release in stimulated human monocytes. Innate Immunity. ISSN 1753-4259. 21(4), s. 429–449. doi: 10.1177/1753425914547743. Fulltekst i vitenarkiv
• Marit Synnøve Hellum, Reidun Øvstebø, Berit Sletbakk Brusletto, Jens Petter Berg, Petter Brandtzæg & Carola Henriksson (2014). Microparticle-associated tissue factor activity correlates with plasma levels of bacterial lipopolysaccharides in meningocoocal septic shock. Thrombosis Research. ISSN 0049-3848. 133(3), s. 507–514. doi: 10.1016/j.thromres.2013.12.031. Fulltekst i vitenarkiv
• Camilla Stormo, Marianne Kristiansen, Robert Lyle, Ole Kristoffer Olstad, Daniel Sachse & Jens Petter Berg [Vis alle 7 forfattere av denne artikkelen] (2014). RNA-sequencing analysis of HepG2 cells treated with atorvastatin. PLOS ONE. 9:e0105836(8). doi: 10.1371/journal.pone.0105836. Fulltekst i vitenarkiv Vis sammendrag

  The cholesterol-lowering drug atorvastatin is among the most prescribed drug in the world. Alternative splicing in a number of genes has been reported to be associated with variable statin response. RNA-seq has proven to be a powerful technique for genome-wide splice variant analysis. In the present study, we sought to investigate atorvastatin responsive splice variants in HepG2 cells using RNA-seq analysis to identify novel candidate genes implicated in cholesterol homeostasis and in the statin response. HepG2 cells were treated with 10 µM atorvastatin for 24 hours. RNA-seq and exon array analyses were performed. The validation of selected genes was performed using Taqman gene expression assays. RNA-seq analysis identified 121 genes and 98 specific splice variants, of which four were minor splice variants to be differentially expressed, 11 were genes with potential changes in their splicing patterns (SYCP3, ZNF195, ZNF674, MYD88, WHSC1, KIF16B, ZNF92, AGER, FCHO1, SLC6A12 and AKAP9), and one was a gene (RAP1GAP) with differential promoter usage. The IL21R transcript was detected to be differentially expressed via RNA-seq and RT-qPCR, but not in the exon array. In conclusion, several novel candidate genes that are affected by atorvastatin treatment were identified in this study. Further studies are needed to determine the biological significance of the atorvastatin responsive splice variants that have been uniquely identified using RNA-seq.

• Thea Berge Vikøren, Jens Petter Berg & Tore Julsrud Berg (2014). Feilkilder ved bruk av hemoglobin A1C. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 134(4), s. 417–421. doi: 10.4045/tidsskr.13.0938. Fulltekst i vitenarkiv
• Sissel Moltu, Daniel Sachse, Elin Wahl Blakstad, Kenneth Strømmen, Britt Nakstad & Astrid Almaas [Vis alle 14 forfattere av denne artikkelen] (2014). Urinary metabolite profiles in premature infants show early postnatal metabolic adaption and maturation. Nutrients. 6(5), s. 1913–1930. doi: 10.3390/nu6051913. Fulltekst i vitenarkiv
• Nils Eiel Steen, Paal Methlie, Steinar Lorentzen, Ingrid Dieset, Monica Aas & Mari Nerhus [Vis alle 11 forfattere av denne artikkelen] (2014). Altered systemic cortisol metabolism in bipolar disorder and schizophrenia spectrum disorders. Journal of Psychiatric Research. ISSN 0022-3956. 52(1), s. 57–62. doi: 10.1016/j.jpsychires.2014.01.017. Fulltekst i vitenarkiv
• Daniel Sachse, Anne Bergljot Bærug, Line Sletner, Kåre I. Birkeland, Britt Nakstad & Anne Karen Jenum [Vis alle 7 forfattere av denne artikkelen] (2014). Urine NMR metabolomics analysis of breastfeeding biomarkers during and after pregnancy in a large prospective cohort study. Scandinavian Journal of Clinical and Laboratory Investigation. ISSN 0036-5513. 74(3), s. 264–272. doi: 10.3109/00365513.2014.884240. Fulltekst i vitenarkiv
• Tove Lekva, Jens Petter Berg, Ansgar Heck, Stine Lyngvi Fougner, Ole Kristoffer Olstad & Geir Andre Ringstad [Vis alle 8 forfattere av denne artikkelen] (2013). Attenuated RORC expression in the presence of EMT progression in somatotroph adenomas following treatment with somatostatin analogs is associated with poor clinical recovery. PLOS ONE. 8(6). doi: 10.1371/journal.pone.0066927. Fulltekst i vitenarkiv
• Tove Lekva, Jens Petter Berg, Robert Lyle, Ansgar Heck, Geir Andre Ringstad & Ole Kristoffer Olstad [Vis alle 10 forfattere av denne artikkelen] (2013). Epithelial Splicing Regulator Protein 1 and Alternative Splicing in Somatotroph Adenomas. Endocrinology. ISSN 0013-7227. 154(9), s. 3331–3343. doi: 10.1210/en.2013-1051. Fulltekst i vitenarkiv
• Jens Petter Berg (2013). Hba1c as a diagnostic tool in diabetes mellitus. Norsk Epidemiologi. ISSN 0803-2491. 23(1), s. 5–8. doi: 10.5324/nje.v23i1.1596. Fulltekst i vitenarkiv
• Johan Arild Evang, Jens Bollerslev, Olivera Casar-Borota, Tove Lekva, Jon-Terje Ramm-Pettersen & Jens Petter Berg (2013). Different levels of various glucocorticoid-regulated genes in corticotroph adenomas. Endocrine. ISSN 1355-008X. 44(1), s. 220–227. doi: 10.1007/s12020-012-9871-0. Fulltekst i vitenarkiv
• Sjur Reppe, Daniel Sachse, Ole Kristoffer Olstad, Vigdis Teig Gautvik, Paul Sanderson & Harish K Datta [Vis alle 8 forfattere av denne artikkelen] (2013). Identification of transcriptional macromolecular associations in human bone using browser based in silico analysis in a giant correlation matrix. Bone. ISSN 8756-3282. 53(1), s. 69–78. doi: 10.1016/j.bone.2012.11.015. Fulltekst i vitenarkiv
• Amrit Kaur Sakhi, Jens Petter Berg & Tore Julsrud Berg (2013). Glyoxalase 1 enzyme activity in erythrocytes and Ala111Glu polymorphism in type 1-diabetes patients. Scandinavian Journal of Clinical and Laboratory Investigation. ISSN 0036-5513. 73(2), s. 175–181. doi: 10.3109/00365513.2013.765028. Fulltekst i vitenarkiv
• Sissel Moltu, Kenneth Strømmen, Elin Wahl Blakstad, Astrid Almaas, Ane Cecilie Westerberg & Kristin Brække [Vis alle 13 forfattere av denne artikkelen] (2013). Enhanced feeding in very-low-birth-weight infants may cause electrolyte disturbances and septicemia - A randomized, controlled trial. Clinical Nutrition. ISSN 0261-5614. 32(2), s. 207–212. doi: 10.1016/j.clnu.2012.09.004. Fulltekst i vitenarkiv
• Rune Jonassen, Tor Endestad, Alexander Neumeister, Kari Bente Foss Haug, Jens Petter Berg & Nils Inge Landrø (2012). Serotonin Transporter Polymorphism Modulates N-Back Task Performance and fMRI BOLD Signal Intensity in Healthy Women. PLOS ONE. 7(1). doi: 10.1371/journal.pone.0030564. Fulltekst i vitenarkiv
• Rune Jonassen, Tor Endestad, Alexander Neumeister, Kari Bente Foss, Jens Petter Berg & Nils Inge Landrø (2012). The effects of the serotonin transporter polymorphism and age on frontal white matter integrity in healthy adult women. Frontiers in Human Neuroscience. 6. doi: 10.3389/fnhum.2012.00019. Fulltekst i vitenarkiv
• Unni Gopinathan, Reidun Øvstebø, Ole Kristoffer Olstad, Berit Sletbakk Brusletto, Hans Christian Aass & Peter Kierulf [Vis alle 8 forfattere av denne artikkelen] (2012). Global Effect of Interleukin-10 on the Transcriptional Profile Induced by Neisseria meningitidis in Human Monocytes. Infection and Immunity. ISSN 0019-9567. 80(11), s. 4046–4054. doi: 10.1128/IAI.00386-12. Fulltekst i vitenarkiv
• Daniel Sachse, Line Sletner, Kjersti Mørkrid, Anne Karen Jenum, Kåre I. Birkeland & Frode Rise [Vis alle 8 forfattere av denne artikkelen] (2012). Metabolic Changes in Urine during and after Pregnancy in a Large, Multiethnic Population-Based Cohort Study of Gestational Diabetes. PLOS ONE. 7(12). doi: 10.1371/journal.pone.0052399. Fulltekst i vitenarkiv Vis sammendrag

  This study aims to identify novel markers for gestational diabetes (GDM) in the biochemical profile of maternal urine using NMR metabolomics. It also catalogs the general effects of pregnancy and delivery on the urine profile. Urine samples were collected at three time points (visit V1: gestational week 8–20; V2: week 28±2; V3:10–16 weeks post partum) from participants in the STORK Groruddalen program, a prospective, multiethnic cohort study of 823 healthy, pregnant women in Oslo, Norway, and analyzed using 1H-NMR spectroscopy. Metabolites were identified and quantified where possible. PCA, PLS-DA and univariate statistics were applied and found substantial differences between the time points, dominated by a steady increase of urinary lactose concentrations, and an increase during pregnancy and subsequent dramatic reduction of several unidentified NMR signals between 0.5 and 1.1 ppm. Multivariate methods could not reliably identify GDM cases based on the WHO or graded criteria based on IADPSG definitions, indicating that the pattern of urinary metabolites above micromolar concentrations is not influenced strongly and consistently enough by the disease. However, univariate analysis suggests elevated mean citrate concentrations with increasing hyperglycemia. Multivariate classification with respect to ethnic background produced weak but statistically significant models. These results suggest that although NMR-based metabolomics can monitor changes in the urinary excretion profile of pregnant women, it may not be a prudent choice for the study of GDM.

• Marianne Kristiansen, Camilla Stormo, Runa Marie Grimholt, Jens Petter Berg & Armin Piehler (2012). Copy number variations of the ATP-binding cassette transporter ABCC6 gene and its pseudogenes. BMC Research Notes. 5. doi: 10.1186/1756-0500-5-425. Fulltekst i vitenarkiv Vis sammendrag

  Background The ATP-binding cassette transporter ABCC6 gene is located on chromosome 16 between its two pseudogenes (ABCC6P1 and ABCC6P2). Previously, we have shown that ABCC6P1 is transcribed and affects ABCC6 at the transcriptional level. In this study we aimed to determine copy number variations of ABCC6, ABCC6P1 and ABCC6P2 in different populations. Moreover, we sought to study the transcription pattern of ABCC6 and ABCC6 pseudogenes in 39 different human tissues. Findings Genomic DNA from healthy individuals from five populations, Chinese (n = 24), Middle East (n = 20), Mexicans (n = 24), Caucasians (n = 50) and Africans (n = 24), were examined for copy number variations of ABCC6 and its pseudogenes by pyrosequencing and quantitative PCR. Copy number variation of ABCC6 was very rare (2/142; 1.4%). However, one or three copies of ABCC6P1 were relatively common (3% and 8%, respectively). Only one person had a single copy of ABCC6P2 while none had three copies. In Chinese, deletions or duplications of ABCC6P1 were more frequent than in any other population (9/24; 37.5%). The transcription pattern of ABCC6P2 was highly similar to ABCC6 and ABCC6P1, with highest transcription in liver and kidney. Interestingly, the total transcription level of pseudogenes, ABCC6P1 + ABCC6P2, was higher than ABCC6 in most tissues, including liver and kidney. Conclusions Copy number variations of the ABCC6 pseudogenes are quite common, especially in populations of Chinese ancestry. The expression pattern of ABCC6P2 in 39 human tissues was highly similar to that of ABCC6 and ABCC6P1 suggesting similar regulatory mechanisms for ABCC6 and its pseudogenes.

• Rolf Jorde, Henrik Schirmer, Tom Wilsgaard, Ragnar Martin Joakimsen, Ellisiv B. Mathiesen & Inger Njølstad [Vis alle 11 forfattere av denne artikkelen] (2012). Polymorphisms Related to the Serum 25-Hydroxyvitamin D Level and Risk of Myocardial Infarction, Diabetes, Cancer and Mortality. The Tromsø Study. PLOS ONE. 7(5). doi: 10.1371/journal.pone.0037295. Fulltekst i vitenarkiv Vis sammendrag

  Low serum 25(OH)D levels are associated with cardiovascular risk factors, and also predict future myocardial infarction (MI), type 2 diabetes (T2DM), cancer and all-cause mortality. Recently several single nucleotide polymorphisms (SNPs) associated with serum 25-hydroxyvitamin D (25(OH)D) level have been identified. If these relations are causal one would expect a similar association between these SNPs and health. DNA was prepared from subjects who participated in the fourth survey of the Tromsø Study in 1994–1995 and who were registered with the endpoints MI, T2DM, cancer or death as well as a randomly selected control group. The endpoint registers were complete up to 2007–2010. Genotyping was performed for 17 SNPs related to the serum 25(OH)D level. A total of 9528 subjects were selected for genetic analyses which were successfully performed for at least one SNP in 9471 subjects. Among these, 2025 were registered with MI, 1092 with T2DM, 2924 with cancer and 3828 had died. The mean differences in serum 25(OH)D levels between SNP genotypes with the lowest and highest serum 25(OH)D levels varied from 0.1 to 7.8 nmol/L. A genotype score based on weighted risk alleles regarding low serum 25(OH)D levels was established. There was no consistent association between the genotype score or individuals SNPs and MI, T2DM, cancer, mortality or risk factors for disease. However, for rs6013897 genotypes (located at the 24-hydroxylase gene (CYP24A1)) there was a significant association with breast cancer (P<0.05). Our results do not support nor exclude a causal relationship between serum 25(OH)D levels and MI, T2DM, cancer or mortality, and our observation on breast cancer needs confirmation. Further genetic studies are warranted, particularly in populations with vitamin D deficiency.

• Marit Synnøve Hellum, Reidun Øvstebø, Anne-Marie Siebke, Jens Petter Berg, Petter Brandtzæg & Carola Henriksson (2012). Microparticle-associated tissue factor activity measured with the Zymuphen MP-TF kit and the calibrated automated thrombogram assay. Blood Coagulation and Fibrinolysis. ISSN 0957-5235. 23(6), s. 520–526. doi: 10.1097/MBC.0b013e328354a256. Fulltekst i vitenarkiv
• Reidun Øvstebø, Hans Christian Aass, Kari Bente Foss, Anne-Marie Siebke, Unni Gopinathan & Peter Kierulf [Vis alle 9 forfattere av denne artikkelen] (2012). LPS from Neisseria meningitidis is crucial for inducing monocyte- and microparticle-associated tissue factor activity but not for tissue factor expression. Innate Immunity. ISSN 1753-4259. 18(4), s. 580–591. doi: 10.1177/1753425911428230. Fulltekst i vitenarkiv
• Camilla Stormo, Marianne Kristiansen, Runa Marie Grimholt, Jens Petter Berg & Armin Piehler (2012). A novel 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) splice variant with an alternative exon 1 potentially encoding an extended N-terminus. BMC Molecular Biology. 13. doi: 10.1186/1471-2199-13-29. Fulltekst i vitenarkiv Vis sammendrag

  Background The major rate-limiting enzyme for de novo cholesterol synthesis is 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR). HMGCR is sterically inhibited by statins, the most commonly prescribed drugs for the prevention of cardiovascular events. Alternative splicing of HMGCR has been implicated in the control of cholesterol homeostasis. The aim of this study was to identify novel alternatively spliced variants of HMGCR with potential physiological importance. Results Bioinformatic analyses predicted three novel HMGCR transcripts containing an alternative exon 1 (HMGCR-1b, -1c, -1d) compared with the canonical transcript (HMGCR-1a). The open reading frame of the HMGCR-1b transcript potentially encodes 20 additional amino acids at the N-terminus, compared with HMGCR-1a. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was used to examine the mRNA levels of HMGCR in different tissues; HMGCR-1a was the most highly expressed variant in most tissues, with the exception of the skin, esophagus, and uterine cervix, in which HMGCR-1b was the most highly expressed transcript. Atorvastatin treatment of HepG2 cells resulted in increased HMGCR-1b mRNA levels, but unaltered proximal promoter activity compared to untreated cells. In contrast, HMGCR-1c showed a more restricted transcription pattern, but was also induced by atorvastatin treatment. Conclusions The gene encoding HMGCR uses alternative, mutually exclusive exon 1 sequences. This contributes to an increased complexity of HMGCR transcripts. Further studies are needed to investigate whether HMGCR splice variants identified in this study are physiologically functional.

• Tove Lekva, Jens Petter Berg, Stine Lyngvi Fougner, Ole Kristoffer Olstad, Thor Ueland & Jens Bollerslev (2012). Gene Expression Profiling Identifies ESRP1 as a Potential Regulator of Epithelial Mesenchymal Transition in Somatotroph Adenomas from a Large Cohort of Patients with Acromegaly. Journal of Clinical Endocrinology and Metabolism (JCEM). ISSN 0021-972X. 97(8), s. E1506–E1514. doi: 10.1210/jc.2012-1760. Fulltekst i vitenarkiv
• Stine Lyngvi Fougner, Olivera Casar Borota, Ansgar Heck, Jens Petter Berg & Jens Bollerslev (2012). Adenoma granulation pattern correlates with clinical variables and effect of somatostatin analogue treatment in a large series of patients with acromegaly. Clinical Endocrinology. ISSN 0300-0664. 76(1), s. 96–102. doi: 10.1111/j.1365-2265.2011.04163.x. Fulltekst i vitenarkiv
• Hans Christian D. Aass, Reidun Øvstebø, Anne-Marie S. Trøseid, Peter Kierulf, Jens Petter Berg & Carola Elisabeth Henriksson (2011). Fluorescent particles in the antibody solution result in false TF- and CD14-positive microparticles in flow cytometric analysis. Cytometry Part A. ISSN 1552-4922. 79A(12), s. 990–999. doi: 10.1002/cyto.a.21147. Fulltekst i vitenarkiv
• Johan Arild Evang, Jens Petter Berg, Olivera Casar Borota, Tove Lekva, Marianne Kristiansen & Jon-Terje Ramm-Pettersen [Vis alle 7 forfattere av denne artikkelen] (2011). Reduced levels of E-cadherin correlate with progression of corticotroph pituitary tumours. Clinical Endocrinology. ISSN 0300-0664. 75(6), s. 811–818. doi: 10.1111/j.1365-2265.2011.04109.x. Fulltekst i vitenarkiv

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• Tor-Arne Hagve & Jens Petter Berg (2019). Klinisk biokjemi og fysiologi, 6. utgave. Gyldendal Akademisk. ISBN 9788205527881. 464 s. Fulltekst i vitenarkiv
• Tor-Arne Hagve & Jens Petter Berg (2015). Klinisk biokjemi og fysiologi. Gyldendal Akademisk. ISBN 9788205463677. 443 s. Fulltekst i vitenarkiv

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• Tanja Storsul, Jens Petter Berg, Henrik Urdal, Gunnar Sivertsen & Vidar Røeggen (2024). Fortsatt behov for forsker­involvering og kvalitets­orientering. Fulltekst i vitenarkiv
• Tanja Storsul, Jens Petter Berg, Henrik Urdal, Gunnar Sivertsen & Vidar Røeggen (2023). Hvordan bør framtidas indikator for publisering være? Khrono.no. ISSN 1894-8995. Fulltekst i vitenarkiv
• Julian Eek Mariampillai, Lene Vernås Halvorsen, Anne Cecilie Kjeldsen Larstorp, Sondre Heimark, Bård Waldum-Grevbo & Sverre Kjeldsen [Vis alle 10 forfattere av denne artikkelen] (2023). Diabetes og kronisk nyresykdom. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 143(12). doi: 10.4045/tidsskr.22.0822. Fulltekst i vitenarkiv
• Jens Petter Berg & Ivar Prydz Gladhaug (2020). Disputasen er en del av doktorgradsproven. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 140(9), s. 1–3. doi: 10.4045/tidsskr.20.0328. Fulltekst i vitenarkiv
• Jens Petter Berg & Kiarash Tazmini (2019). Utredning av sykdom i hypofysen, Klinisk biokjemi og fysiologi, 6. utgave. Gyldendal Akademisk. ISSN 9788205527881. s. 370–381. Fulltekst i vitenarkiv
• Jens Petter Berg (2019). Utredning av sykdom i binyrene, Klinisk biokjemi og fysiologi, 6. utgave. Gyldendal Akademisk. ISSN 9788205527881. s. 382–393. Fulltekst i vitenarkiv
• Jens Petter Berg & Ivar Prydz Gladhaug (2019). Viktig at prøveforelesningens hensikt blir oppfylt. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 139(16), s. 1534–1534. doi: 10.4045/tidsskr.19.0646. Fulltekst i vitenarkiv
• Lutz Schwettmann, Jens Petter Berg & Sverre Sandberg (2018). HbA1c skal angis i mmol/mol. Tidsskrift for Den norske legeforening (Tidsskriftet). ISSN 0029-2001. 138(15), s. 1404–1405. doi: 10.4045/tidsskr.18.0633. Fulltekst i vitenarkiv
• Sigrid Beitland, Espen Rostrup Nakstad, Jens Petter Berg, Anne-Marie Siebke Trøseid, Berit Sletbakk Brusletto & Cathrine Brunborg [Vis alle 7 forfattere av denne artikkelen] (2018). Urine biomarkers may early predict acute kidney injury and outcome after out-of-hospital cardiac arrest. Intensive Care Medicine Experimental. 6. doi: 10.1186/s40635-018-0201-6. Fulltekst i vitenarkiv
• Karl Mårild, Maria Vistnes, German Tapia, Øivind Midttun, Per Magne Ueland & Marte K Viken [Vis alle 10 forfattere av denne artikkelen] (2017). Midpregnancy and cord blood immunologic biomarkers, HLA genotype, and pediatric celiac disease. Journal of Allergy and Clinical Immunology. ISSN 0091-6749. 139(5), s. 1696–1698. doi: 10.1016/j.jaci.2016.10.016. Fulltekst i vitenarkiv
• Jens Petter Berg (2015). Aromatase. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg (2015). antinukleære faktorer. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg & Johan Halse (2015). Fenylketonuri. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg (2015). Androstenedion. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg & Ivar Øye (2015). Dopingmidler. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg & Ivar Øye (2015). Dopingkontroll. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg & Helge Opdahl (2015). Diabeteskoma. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Jens Petter Berg & Stein Vaaler (2015). Diabetes. I Anne Marit Godal (Red.), Store norske leksikon (snl.no 2015). Store norske leksikon AS. Fulltekst i vitenarkiv
• Elizaveta Vereshchagina, Geir Uri Jensen, Michal Marek Mielnik, Jens Petter Berg & Reidun Øvstebø (2015). A versatile fabrication and assembly approach for microfluidic capturing of extracellular vesicles. Fulltekst i vitenarkiv Vis sammendrag

  Cells communicate by means of "messengers" known as extracellular vesicles, i.e. small (30‐1000 nm) cell derived vesicles released from almost all eukaryotic cells into their extracellular environment and containing a variety of proteins and RNAs [1]. It has been foreseen that the next generation of biomarkers for disease diagnostics and prognostics may strongly depend on the vesicles being efficiently isolated, quantified and analyzed by e.g. reliable, high‐throughput and possibly easy‐to‐operate microfluidic devices. The results reported here extend the previously reported work by Chen et al. [2]: (i) the fabrication approach is based on silicon as a micromolding master, which offers better dimensional control and durability than SU‐8 masters, (ii) a staggered herringbone micromixer [3] is introduced in three different channel configurations , (iii) the device assembly allows straightforward integration of a large variety of surface chemistries by introducing prefunctionalized glass slides; (iv) individual functionalization of the glass slide and the PDMS replica prior to assembly permits combination of two differently biofunctionalized surfaces within the same fluidic device; (v) isolated extracellular vesicles can be accessed directly for a variety of post‐analyses by opening the device assembly.

• Aina Jansen, Marit Aralt Skaug, Jens Petter Berg & Jan Aaseth (2014). Overvekt og miljøgifter. Fulltekst i vitenarkiv
• Sjur Reppe, D. Sachse, Ole Kristoffer Olstad, Vigdis Teig Gautvik, P.L. Sanderson & H.K. Datta [Vis alle 8 forfattere av denne artikkelen] (2012). Identification of human transcriptional macromolecular associations using browser based in silico analysis in a giant correlation matrix. Bone. ISSN 8756-3282. 50, s. S109–S109. doi: 10.1016/j.bone.2012.02.334. Fulltekst i vitenarkiv
• Jens Petter Berg (2011). Kapittel 17 Sykdommer i endokrine organer. I Stein Ørn, Johnny Mjell & Edvin Bach-Gansmo (Red.), Sykdom og behandling. Gyldendal Akademisk. ISSN 9788205323605. s. 363–378. Fulltekst i vitenarkiv
• Merisa Abusdal & Jens Petter Berg (2026). Corticotroph pituitary adenoma: hormone production and invasiveness features. Universitetet i Oslo. ISSN 9788234808937. Fulltekst i vitenarkiv Vis sammendrag

  Corticotroph tumors, a subtype of pituitary neuroendocrine tumors (PitNETs). Functioning corticotroph adenomas (FCA) secrete excess biologically active adrenocorticotropic hormone (ACTH), causing Cushing’s disease, whereas silent corticotroph adenomas (SCA) are typically diagnosed as non-functioning pituitary adenomas (NFPAs) and present with mass-related symptoms. Despite their shared lineage, SCA tend to be larger, more aggressive, and more prone to recurrence. Their hormonal silence remains poorly understood, but may involve impaired proopiomelanocortin (POMC) processing, defective secretory pathways, and reduced activity of the prohormone convertase PC1/3 (PCSK1). This PhD project investigated factors that may contribute to hormonal silence and aggressiveness in corticotroph tumors, focusing on the PC1/3 inhibitor PCSK1N, the cytoskeletal regulator PDZ and LIM domain protein 1 (PDLIM1), and endoplasmic reticulum (ER) stress. We quantified PCSK1N and corticotroph marker expression in patient-derived FCA and SCA samples and assessed associations with clinical features. We induced ER stress in mouse corticotroph tumor cells and primary human FCA cultures to examine its effects on cell survival and ACTH production. Lastly, PDLIM1 was overexpressed in mouse corticotroph tumor cells to assess its effects on cell viability, migration, and morphology related to invasive behavior. We found that corticotroph cells rely on effective ER function for ACTH production and secretion. ER stress increased PCSK1N expression and reduced secreted ACTH, suggesting a potential mechanism contributing to hormonal silence in SCA. PDLIM1 expression was higher in SCA than in FCA, and its overexpression promoted cell viability and migration in vitro, indicating a possible role in tumor aggressiveness. These findings highlight ER stress, PCSK1N, and PDLIM1 as potential contributors that influence hormonal silence and invasive behavior in corticotroph tumors.

• Tanja Storsul, Jens Petter Berg, Henrik Urdal, Gunnar Sivertsen & Vidar Røeggen (2024). Kvalitet i vitenskapelig publisering. Organisering og innretning av publiseringsindikatoren, publiseringsstatistikken og kanalregisteret. En utredning for Kunnskapsdepartementet. Det nasjonale publiseringsutvalget. Fulltekst i vitenarkiv

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