Sahar Hassani

• Jin, Yang; Harvey, Thomas Nelson; Bartosova, Zdenka; Hassani, Sahar; Bruheim, Per & Sandve, Simen Rød [Vis alle 7 forfattere av denne artikkelen] (2021). Diet and Life Stage-Associated Lipidome Remodeling in Atlantic Salmon. Journal of Agricultural and Food Chemistry. ISSN 0021-8561. 69(12), s. 3787–3796. doi: 10.1021/acs.jafc.0c07281. Fulltekst i vitenarkiv Vis sammendrag

  Salmon is an important source of long-chain highly unsaturated fatty acids (LC-HUFAs) such as 22:6n-3 [docosahexaenoic acid (DHA)]. In the present study, we conducted two identical experiments on salmon in freshwater (FW) and seawater (SW) stages, with a diet switch from fish oil (high in LC-HUFA) to vegetable oil (low in LC-HUFA) and vice versa. Our aim was to investigate the diet and life stage-specific features of lipid uptake (gut), processing (liver), and deposition (muscle). The lipid composition changed much faster in the gut of SW fish relative to FW fish, suggesting that the former had a higher rate of lipid absorption and transport. SW fish also had higher expression of phospholipid synthesis and lipoprotein formation genes in the gut, whereas FW fish had higher expression of lipid synthesis genes in the liver. All phospholipids except PC-44:12 and PE-44:12 were less abundant in SW, suggesting that SW fish have a higher requirement for DHA.

• Drange, Ole Kristian; Smeland, Olav Bjerkehagen; Shadrin, Alexey A.; Finseth, Per Ivar; Witoelar, Aree & Frei, Oleksandr [Vis alle 52 forfattere av denne artikkelen] (2019). Genetic Overlap Between Alzheimer’s Disease and Bipolar Disorder Implicates the MARK2 and VAC14 Genes. Frontiers in Neuroscience. ISSN 1662-4548. 13. doi: 10.3389/fnins.2019.00220. Fulltekst i vitenarkiv Vis sammendrag

  Background: Alzheimer’s disease (AD) and bipolar disorder (BIP) are complex traits influenced by numerous common genetic variants, most of which remain to be detected. Clinical and epidemiological evidence suggest that AD and BIP are related. However, it is not established if this relation is of genetic origin. Here, we applied statistical methods based on the conditional false discovery rate (FDR) framework to detect genetic overlap between AD and BIP and utilized this overlap to increase the power to identify common genetic variants associated with either or both traits. Methods: We obtained genome wide association studies data from the International Genomics of Alzheimer’s Project part 1 (17,008 AD cases and 37,154 controls) and the Psychiatric Genetic Consortium Bipolar Disorder Working Group (20,352 BIP cases and 31,358 controls). We used conditional QQ-plots to assess overlap in common genetic variants between AD and BIP. We exploited the genetic overlap to re-rank test-statistics for AD and BIP and improve detection of genetic variants using the conditional FDR framework. Results: Conditional QQ-plots demonstrated a polygenic overlap between AD and BIP. Using conditional FDR, we identified one novel genomic locus associated with AD, and nine novel loci associated with BIP. Further, we identified two novel loci jointly associated with AD and BIP implicating the MARK2 gene (lead SNP rs10792421, conjunctional FDR = 0.030, same direction of effect) and the VAC14 gene (lead SNP rs11649476, conjunctional FDR = 0.022, opposite direction of effect). Conclusion: We found polygenic overlap between AD and BIP and identified novel loci for each trait and two jointly associated loci. Further studies should examine if the shared loci implicating the MARK2 and VAC14 genes could explain parts of the shared and distinct features of AD and BIP.

• Helgeland, Jon; Tomic, Oliver; Hansen, Tonya Moen; Kristoffersen, Doris Tove; Hassani, Sahar & Lindahl, Anne Karin (2019). Postoperative wound dehiscence after laparotomy: a useful healthcare quality indicator? A cohort study based on Norwegian hospital administrative data. BMJ Open. 9(4). doi: 10.1136/bmjopen-2018-026422. Fulltekst i vitenarkiv Vis sammendrag

  Objectives Postoperative wound dehiscence (PWD) is a serious complication to laparotomy, leading to higher mortality, readmissions and cost. The aims of the present study are to investigate whether risk adjusted PWD rates could reliably differentiate between Norwegian hospitals, and whether PWD rates were associated with hospital characteristics such as hospital type and laparotomy volume. Design Observational study using patient administrative data from all Norwegian hospitals, obtained from the Norwegian Patient Registry, for the period 2011–2015, and linked using the unique person identification number. Participants All patients undergoing laparotomy, aged at least 15 years, with length of stay at least 2 days and no diagnosis code for immunocompromised state or relating to pregnancy, childbirth and puerperium. The final data set comprised 66 925 patients with 78 086 laparotomy episodes from 47 hospitals. Outcomes The outcome was wound dehiscence, identified by the presence of a wound reclosure code, risk adjusted for patient characteristics and operation type. Results The final data set comprised 1477 wound dehiscences. Crude PWD rates varied from 0% to 5.1% among hospitals, with an overall rate of 1.89%. Three hospitals with statistically significantly higher PWD than average were identified, after case mix adjustment and correction for multiple comparisons. Hospital volume was not associated with PWD rate, except that hospitals with very few laparotomies had lower PWD rates. Conclusions Among Norwegian hospitals, there is considerable variation in PWD rate that cannot be explained by operation type, age or comorbidity. This warrants further investigation into possible causes, such as surgical technique, perioperative procedures or handling of complications. The risk adjusted PWD rate after laparotomy is a candidate quality indicator for Norwegian hospitals.

• Hughes, Timothy; Sønderby, Ida Elken; Polushina, Tatiana; Hansson, Lars Johan Axel; Holmgren, Asbjørn & Athanasiu, Lavinia [Vis alle 24 forfattere av denne artikkelen] (2018). Elevated expression of a minor isoform of ANK3 is a risk factor for bipolar disorder. Translational Psychiatry. 8(210), s. 1–10. doi: 10.1038/s41398-018-0175-x. Fulltekst i vitenarkiv Vis sammendrag

  Ankyrin-3 (ANK3) is one of the few genes that have been consistently identified as associated with bipolar disorder by multiple genome-wide association studies. However, the exact molecular basis of the association remains unknown. A rare loss-of-function splice-site SNP (rs41283526*G) in a minor isoform of ANK3 (incorporating exon ENSE00001786716) was recently identified as protective of bipolar disorder and schizophrenia. This suggests that an elevated expression of this isoform may be involved in the etiology of the disorders. In this study, we used novel approaches and data sets to test this hypothesis. First, we strengthen the statistical evidence supporting the allelic association by replicating the protective effect of the minor allele of rs41283526 in three additional large independent samples (meta-analysis p-values: 6.8E–05 for bipolar disorder and 8.2E–04 for schizophrenia). Second, we confirm the hypothesis that both bipolar and schizophrenia patients have a significantly higher expression of this isoform than controls (p-values: 3.3E–05 for schizophrenia and 9.8E–04 for bipolar type I). Third, we determine the transcription start site for this minor isoform by Pacific Biosciences sequencing of full-length cDNA and show that it is primarily expressed in the corpus callosum. Finally, we combine genotype and expression data from a large Norwegian sample of psychiatric patients and controls, and show that the risk alleles in ANK3 identified by bipolar disorder GWAS are located near the transcription start site of this isoform and are significantly associated with its elevated expression. Together, these results point to the likely molecular mechanism underlying ANK3´s association with bipolar disorder.

• Srinivasan, Saurabh; Bettella, Francesco; Hassani, Sahar; Wang, Yunpeng; Witoelar, Aree & Schork, Andrew J. [Vis alle 13 forfattere av denne artikkelen] (2017). Probing the association between early evolutionary markers and schizophrenia. PLOS ONE. 12:e0169227(1), s. 1–15. doi: 10.1371/journal.pone.0169227. Fulltekst i vitenarkiv
• Hassani, Sahar; Lindman, Anja Schou; Kristoffersen, Doris Tove; Tomic, Oliver & Helgeland, Jon (2015). 30-Day Survival Probabilities as a Quality Indicator for Norwegian Hospitals: Data Management and Analysis. PLOS ONE. 10(9). doi: 10.1371/journal.pone.0136547. Fulltekst i vitenarkiv
• Perisic, Nebojsa; Afseth, Nils Kristian; Ofstad, Ragni; Hassani, Sahar & Kohler, Achim (2013). Characterising protein, salt and water interactions with combined vibrational spectroscopic techniques. Food Chemistry. ISSN 0308-8146. 138(1), s. 679–686. doi: 10.1016/j.foodchem.2012.10.117. Fulltekst i vitenarkiv
• Hassani, Sahar; Hanafi, Mohamed; Qannari, El Mostafa & Kohler, Achim (2013). Deflation strategies for multi-block principal component analysis revisited. Chemometrics and Intelligent Laboratory Systems. ISSN 0169-7439. 120, s. 154–168. doi: 10.1016/j.chemolab.2012.08.011. Fulltekst i vitenarkiv
• Ottestad, Inger; Hassani, Sahar; Borge, Grethe iren andersen; Kohler, Achim; Vogt, Kjell gjermund & Hyøtylainen, Tuulia [Vis alle 11 forfattere av denne artikkelen] (2012). Fish oil supplementation alters the plasma lipidomic profile and increases long-chain PUFAs of phospholipids and triglycerides in healthy subjects. PLOS ONE. 7(8). doi: 10.1371/journal.pone.0042550. Fulltekst i vitenarkiv Vis sammendrag

  Background While beneficial health effects of fish and fish oil consumption are well documented, the incorporation of n-3 polyunsaturated fatty acids in plasma lipid classes is not completely understood. The aim of this study was to investigate the effect of fish oil supplementation on the plasma lipidomic profile in healthy subjects. Methodology/Principal Findings In a double-blinded randomized controlled parallel-group study, healthy subjects received capsules containing either 8 g/d of fish oil (FO) (1.6 g/d EPA+DHA) (n = 16) or 8 g/d of high oleic sunflower oil (HOSO) (n = 17) for seven weeks. During the first three weeks of intervention, the subjects completed a fully controlled diet period. BMI and total serum triglycerides, total-, LDL- and HDL-cholesterol were unchanged during the intervention period. Lipidomic analyses were performed using Ultra Performance Liquid Chromatography (UPLC) coupled to electrospray ionization quadrupole time-of-flight mass spectrometry (QTOFMS), where 568 lipids were detected and 260 identified. Both t-tests and Multi-Block Partial Least Square Regression (MBPLSR) analysis were performed for analysing differences between the intervention groups. The intervention groups were well separated by the lipidomic data after three weeks of intervention. Several lipid classes such as phosphatidylcholine, phosphatidylethanolamine, lysophosphatidylcholine, sphingomyelin, phosphatidylserine, phosphatidylglycerol, and triglycerides contributed strongly to this separation. Twenty-three lipids were significantly decreased (FDR<0.05) in the FO group after three weeks compared with the HOSO group, whereas fifty-one were increased including selected phospholipids and triglycerides of long-chain polyunsaturated fatty acids. After seven weeks of intervention the two intervention groups showed similar grouping. Conclusions/Significance In healthy subjects, fish oil supplementation alters lipid metabolism and increases the proportion of phospholipids and triglycerides containing long-chain polyunsaturated fatty acids. Whether the beneficial effects of fish oil supplementation may be explained by a remodeling of the plasma lipids into phospholipids and triglycerides of long-chain polyunsaturated fatty acids needs to be further investigated.

• Hassani, Sahar; Martens, Harald; Qannari, El Mostafa & Kohler, Achim (2012). Degrees of freedom estimation in Principal Component Analysis and Consensus Principal Component Analysis. Chemometrics and Intelligent Laboratory Systems. ISSN 0169-7439. 118, s. 246–259. doi: 10.1016/j.chemolab.2012.05.015. Fulltekst i vitenarkiv
• Hassani, Sahar; Martens, Harald; Qannari, El Mostafa; Hanafi, Mohamed & Kohler, Achim (2012). Model validation and error estimation in multi-block partial least squares regression. Chemometrics and Intelligent Laboratory Systems. ISSN 0169-7439. 117, s. 42–53. doi: 10.1016/j.chemolab.2011.06.001. Fulltekst i vitenarkiv
• Hassani, Sahar; Martens, Harald; Qannari, El Mostafa; Hanafi, Mohamed; Borge, Grethe iren andersen & Kohler, Achim (2010). Analysis of -omics data: Graphical interpretation- and validation tools in multi-block methods. Chemometrics and Intelligent Laboratory Systems. ISSN 0169-7439. 104(1), s. 140–153. doi: 10.1016/j.chemolab.2010.08.008. Fulltekst i vitenarkiv Vis sammendrag

  As systems biology develops, various types of high-throughput -omics data become rapidly available. An increasing challenge is to analyze such massive data, interpret the results and validate the findings. Data analysis for most of the omics-techniques is in a fledgling immature stage. Alone the dimensionality of the data tables calls for new ways to reveal structure in the data, without cognitive overflow and excessive false discovery rate. Multi-block methods have been developed and adapted in order to find common variation patterns in data and depict these findings on graphical displays while providing tools to enhance the interpretation of the outcomes. In particular, multi-block methods based on latent variables are powerful tools to study block and global variation patterns, e.g. by inspecting block and global score plots. These methods can be used to achieve a graphical overview over sample and variable variation patterns in an efficient way. However, a visual detection of patterns may be subjective and, therefore, there is a need for validation tools. In this paper tools for validation of visually identified patterns in multi-block results are presented. Cross-validated estimates of Root Mean Square Error (RMSE) for block results are introduced for estimating the number of relevant PCs of the Consensus Principal Component Analysis (CPCA) models. Furthermore, important variables are identified by approximate t-tests based on Procrustes-corrected jackknifing. For the assessment of the stability of score patterns, block stability plots are introduced. Outliers can be revealed graphically on block and global level by stability plots. (C) 2010 Elsevier B.V. All rights reserved.

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• Lindman, Anja Schou; Tomic, Oliver; Kristoffersen, Doris Tove; Hassani, Sahar & Helgeland, Jon (2014). 30 days readmission among the elderly – a new quality indicator for hospital performance in Norway. Fulltekst i vitenarkiv
• Ottestad, Inger; Vogt, Kjell Gjermund; Myhrstad, Mari; Borge, Grethe Iren Andersen; Hassani, Sahar & Kohler, Achim [Vis alle 16 forfattere av denne artikkelen] (2012). Effect of oxidized fish oil on oxidative stress markers and plasma lipidome profile.A randomized controlled trial in healthy subjects. Fulltekst i vitenarkiv
• Hassani, Sahar; Martens, Harald; Qannari, El Mostafa; Borge, Grethe Iren Andersen & Kohler, Achim (2011). Analysis of metabolomics data by means of multi-block methods. Fulltekst i vitenarkiv
• Perisic, Nebojsa; Afseth, Nils Kristian; Ofstad, Ragni; Hassani, Sahar & Kohler, Achim (2010). Integrating information obtained by different spectroscopic techniques by multi-matrix techniques. Fulltekst i vitenarkiv
• Perisic, Nebojsa; Afseth, Nils Kristian; Ofstad, Ragni; Hassani, Sahar & Kohler, Achim (2010). Integrating information obtained by different spectroscopic techniques by multi-matrix techniques. Fulltekst i vitenarkiv
• Lindman, Anja Schou; Kristoffersen, Doris Tove; Hassani, Sahar; Tomic, Oliver & Helgeland, Jon (2015). 30-dagers reinnleggelse av eldre 2011–2013. Resultater for sykehus og kommuner. Folkehelseinstituttet. ISSN 9788281219502. Fulltekst i vitenarkiv
• Lindman, Anja Schou; Tomic, Oliver; Hassani, Sahar; Kristoffersen, Doris Tove & Helgeland, Jon (2015). 30-dagers overlevelse - institusjonsrapporter - 2. utgave. Norwegian Knowledge Centre for the Heath Services. ISSN 9788281219403. Fulltekst i vitenarkiv
• Lindman, Anja Schou; Hassani, Sahar; Kristoffersen, Doris Tove; Tomic, Oliver; Dimoski, Tomislav & Helgeland, Jon (2014). 30-dagers overlevelse og reinnleggelse ved norske sykehus for 2013. Folkehelseinstituttet. ISSN 9788281219120. Fulltekst i vitenarkiv
• Lindman, Anja Schou; Tomic, Oliver; Hassani, Sahar; Kristoffersen, Doris Tove & Helgeland, Jon (2014). 30-dagers overlevelse. Institusjonsrapporter. Nasjonalt kunnskapssenter for helsetjenesten. ISSN 9788281219328. Fulltekst i vitenarkiv
• Helgeland, Jon; Kristoffersen, Doris Tove; Hassani, Sahar; Dimoski, Tomislav & Lindman, Anja Schou (2013). Overlevelse og reinnleggelser ved norske sykehus for 2012. Folkehelseinstituttet. ISSN 9788281218314. Fulltekst i vitenarkiv

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