| 1. |
- Fresard, Laure, et al.
(författare)
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Identification of rare-disease genes using blood transcriptome sequencing and large control cohorts
- 2019
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Ingår i: Nature Medicine. - : NATURE PUBLISHING GROUP. - 1078-8956 .- 1546-170X. ; 25:6, s. 911-919
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Tidskriftsartikel (refereegranskat)abstract
- It is estimated that 350 million individuals worldwide suffer from rare diseases, which are predominantly caused by mutation in a single gene(1). The current molecular diagnostic rate is estimated at 50%, with whole-exome sequencing (WES) among the most successful approaches(2-5). For patients in whom WES is uninformative, RNA sequencing (RNA-seq) has shown diagnostic utility in specific tissues and diseases(6-8). This includes muscle biopsies from patients with undiagnosed rare muscle disorders(6,9), and cultured fibroblasts from patients with mitochondrial disorders(7). However, for many individuals, biopsies are not performed for clinical care, and tissues are difficult to access. We sought to assess the utility of RNA-seq from blood as a diagnostic tool for rare diseases of different pathophysiologies. We generated whole-blood RNA-seq from 94 individuals with undiagnosed rare diseases spanning 16 diverse disease categories. We developed a robust approach to compare data from these individuals with large sets of RNA-seq data for controls (n = 1,594 unrelated controls and n = 49 family members) and demonstrated the impacts of expression, splicing, gene and variant filtering strategies on disease gene identification. Across our cohort, we observed that RNA-seq yields a 7.5% diagnostic rate, and an additional 16.7% with improved candidate gene resolution.
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| 2. |
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| 3. |
- Bergquist, Annika, et al.
(författare)
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Impact on follow-up strategies in patients with primary sclerosing cholangitis
- 2023
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Ingår i: Liver international (Print). - Chichester, United Kingdom : Wiley-Blackwell Publishing Inc.. - 1478-3223 .- 1478-3231. ; 43:1, s. 127-138
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: Evidence for the benefit of scheduled imaging for early detection of hepatobiliary malignancies in primary sclerosing cholangitis (PSC) is limited. We aimed to compare different follow-up strategies in PSC with the hypothesis that regular imaging improves survival.METHODS: We collected retrospective data from 2,975 PSC patients from 27 centers. Patients were followed from the start of scheduled imaging or in case of clinical follow-up from January 1, 2000, until death or last clinical follow-up alive. The primary endpoint was all-cause mortality.RESULTS: A broad variety of different follow-up strategies were reported. All except one center used regular imaging, ultrasound (US) and/or magnetic resonance imaging (MRI). Two centers used scheduled ERCP in addition to imaging for surveillance purposes. The overall HR (CI95%) for death, adjusted for sex, age and start year of follow-up, were 0.61 (0.47-0.80) for scheduled imaging with and without ERCP; 0.64 (0.48-0.86) for US/MRI and 0.53 (0.37-0.75) for follow-up strategies including scheduled ERCP. The lower risk of death remained for scheduled imaging with and without ERCP after adjustment for cholangiocarcinoma (CCA) or high-grade dysplasia as a time-dependent covariate, HR 0.57 (0.44-0.75). Hepatobiliary malignancy was diagnosed in 175 (5.9%) of the patients at 7.9 years follow-up. Asymptomatic patients (25%) with CCA had better survival if scheduled imaging had been performed.CONCLUSIONS: Follow-up strategies vary considerably across centers. Scheduled imaging was associated with improved survival. Multiple factors may contribute to this result including early tumor detection and increased endoscopic treatment of asymptomatic benign biliary strictures.
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| 4. |
- Chien, Yin-Hsiu, et al.
(författare)
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Mudd's disease (MAT I/III deficiency) : a survey of data for MAT1A homozygotes and compound heterozygotes
- 2015
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Ingår i: Orphanet Journal of Rare Diseases. - : Springer Science and Business Media LLC. - 1750-1172. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Background: This paper summarizes the results of a group effort to bring together the worldwide available data on patients who are either homozygotes or compound heterozygotes for mutations in MAT1A. MAT1A encodes the subunit that forms two methionine adenosyltransferase isoenzymes, tetrameric MAT I and dimeric MAT III, that catalyze the conversion of methionine and ATP to S-adenosylmethionine (AdoMet). Subnormal MAT I/III activity leads to hypermethioninemia. Individuals, with hypermethioninemia due to one of the MAT1A mutations that in heterozygotes cause relatively mild and clinically benign hypermethioninemia are currently often being flagged in screening programs measuring methionine elevation to identify newborns with defective cystathionine beta-synthase activity. Homozygotes or compound heterozygotes for MAT1A mutations are less frequent. Some but not all, such individuals have manifested demyelination or other CNS abnormalities. Purpose of the study: The goals of the present effort have been to determine the frequency of such abnormalities, to find how best to predict whether they will occur, and to evaluate the outcomes of the variety of treatment regimens that have been used. Data have been gathered for 64 patients, of whom 32 have some evidence of CNS abnormalities (based mainly on MRI findings), and 32 do not have such evidence. Results and Discussion: The results show that mean plasma methionine concentrations provide the best indication of the group into which a given patient will fall: those with means of 800 mu M or higher usually have evidence of CNS abnormalities, whereas those with lower means usually do not. Data are reported for individual patients for MAT1A genotypes, plasma methionine, total homocysteine (tHcy), and AdoMet concentrations, liver function studies, results of 15 pregnancies, and the outcomes of dietary methionine restriction and/or AdoMet supplementation. Possible pathophysiological mechanisms that might contribute to CNS damage are discussed, and tentative suggestions are put forth as to optimal management.
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| 5. |
- Dehghan, Abbas, et al.
(författare)
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Genome-Wide Association Study for Incident Myocardial Infarction and Coronary Heart Disease in Prospective Cohort Studies : The CHARGE Consortium
- 2016
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 11:3
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Tidskriftsartikel (refereegranskat)abstract
- Background Data are limited on genome-wide association studies (GWAS) for incident coronary heart disease (CHD). Moreover, it is not known whether genetic variants identified to date also associate with risk of CHD in a prospective setting. Methods We performed a two-stage GWAS analysis of incident myocardial infarction (MI) and CHD in a total of 64,297 individuals (including 3898 MI cases, 5465 CHD cases). SNPs that passed an arbitrary threshold of 5x10(-6) in Stage I were taken to Stage II for further discovery. Furthermore, in an analysis of prognosis, we studied whether known SNPs from former GWAS were associated with total mortality in individuals who experienced MI during follow-up. Results In Stage I 15 loci passed the threshold of 5x10(-6); 8 loci for MI and 8 loci for CHD, for which one locus overlapped and none were reported in previous GWAS meta-analyses. We took 60 SNPs representing these 15 loci to Stage II of discovery. Four SNPs near QKI showed nominally significant association with MI (p-value<8.8x10(-3)) and three exceeded the genome-wide significance threshold when Stage I and Stage II results were combined (top SNP rs6941513: p = 6.2x10(-9)). Despite excellent power, the 9p21 locus SNP (rs1333049) was only modestly associated with MI (HR = 1.09, p-value = 0.02) and marginally with CHD (HR = 1.06, p-value = 0.08). Among an inception cohort of those who experienced MI during follow-up, the risk allele of rs1333049 was associated with a decreased risk of subsequent mortality (HR = 0.90, p-value = 3.2x10(-3)). Conclusions QKI represents a novel locus that may serve as a predictor of incident CHD in prospective studies. The association of the 9p21 locus both with increased risk of first myocardial infarction and longer survival after MI highlights the importance of study design in investigating genetic determinants of complex disorders.
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| 6. |
- Hedin, Charlotte Rose Hawkey, et al.
(författare)
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Effects of Tumor Necrosis Factor Antagonists in Patients With Primary Sclerosing Cholangitis
- 2020
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Ingår i: Clinical Gastroenterology and Hepatology. - : Elsevier BV. - 1542-3565 .- 1542-7714. ; 18:10, s. 2-2304
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Tidskriftsartikel (refereegranskat)abstract
- Background & Aims: Few patients with primary sclerosing cholangitis (PSC) and inflammatory bowel diseases (IBDs) are exposed to tumor necrosis factor (TNF) antagonists because of the often mild symptoms of IBD. We assessed the effects of anti-TNF agents on liver function in patients with PSC and IBD, and their efficacy in treatment of IBD. Methods: We performed a retrospective analysis of 141 patients with PSC and IBD receiving treatment with anti-TNF agents (infliximab or adalimumab) at 20 sites (mostly tertiary-care centers) in Europe and North America. We collected data on the serum level of alkaline phosphatase (ALP). IBD response was defined as either endoscopic response or, if no endoscopic data were available, clinical response, as determined by the treating clinician or measurements of fecal calprotectin. Remission was defined more stringently as endoscopic mucosal healing. We used linear regression analysis to identify factors associated significantly with level of ALP during anti-TNF therapy. Results: Anti-TNF treatment produced a response of IBD in 48% of patients and remission of IBD in 23%. There was no difference in PSC symptom frequency before or after drug exposure. The most common reasons for anti-TNF discontinuation were primary nonresponse of IBD (17%) and side effects (18%). At 3 months, infliximab-treated patients had a median reduction in serum level of ALP of 4% (interquartile range, reduction of 25% to increase of 19%) compared with a median 15% reduction in ALP in adalimumab-treated patients (interquartile range, reduction of 29% to reduction of 4%; P =.035). Factors associated with lower ALP were normal ALP at baseline (P <.01), treatment with adalimumab (P =.090), and treatment in Europe (P =.083). Conclusions: In a retrospective analysis of 141 patients with PSC and IBD, anti-TNF agents were moderately effective and were not associated with exacerbation of PSC symptoms or specific side effects. Prospective studies are needed to investigate the association between use of adalimumab and reduced serum levels of ALP further.
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| 7. |
- Hirschfield, Gideon M, et al.
(författare)
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Ustekinumab for patients with primary biliary cholangitis who have an inadequate response to Ursodeoxycholic Acid: a proof-of-concept study.
- 2016
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Ingår i: Hepatology (Baltimore, Md.). - : Ovid Technologies (Wolters Kluwer Health). - 1527-3350 .- 0270-9139. ; 64:1, s. 189-199
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Tidskriftsartikel (refereegranskat)abstract
- The interleukin (IL)-12 signaling cascade has been associated with primary biliary cholangitis (PBC). This multicenter, open-label, proof-of-concept study evaluated the anti-IL12/23 monoclonal antibody ustekinumab (90 mg subcutaneous at weeks 0 and 4, then every 8 weeks through week 20) in adults with PBC and an inadequate response to ursodeoxycholic acid therapy (i.e., alkaline phosphatase [ALP] >1.67x upper limit of normal [ULN] after ≥6 months). ALP response was defined as a >40% decrease from baseline, and ALP remission as ALP normalization (if baseline ALP 1.67x-2.8x ULN) or <1.67x ULN (if baseline ALP >2.8x ULN). Changes in Enhanced Liver Fibrosis (ELF) scores and serum bile acids were also assessed. At baseline, patients had median disease duration of 3.2 years, median ELF score of 9.8, and highly elevated total bile acid concentration (median: 43.3 µmol/L); 13/20 (65%) patients had baseline ALP >3x ULN. Although steady-state serum ustekinumab concentrations were reached by week 12, no patient achieved ALP response or remission. The median percent ALP reduction from baseline to week 28 was 12.1%. The ELF score decreased slightly from baseline to week 28 (median reduction: 0.173), and total serum bile acid concentrations decreased from baseline to week 28 (median reduction: 8.8 µmol/L). No serious infections or discontinuations due to adverse events were reported through week 28. One patient had a serious upper gastrointestinal hemorrhage considered unrelated to test agent by the investigator.
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| 8. |
- Lynch, Kate D, et al.
(författare)
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Effects of Vedolizumab in Patients with Primary Sclerosing Cholangitis and Inflammatory Bowel Diseases.
- 2020
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Ingår i: Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. - : Elsevier BV. - 1542-7714. ; 18:1
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Tidskriftsartikel (refereegranskat)abstract
- Gut-homing lymphocytes that express the integrin α4β7 and CCR9 might contribute to development of primary sclerosing cholangitis (PSC). Vedolizumab, which blocks the integrin α4β7, is used to treat patients with inflammatory bowel diseases (IBD), but there are few data on its efficacy in patients with PSC. We investigated the effects of vedolizumab in a large international cohort of patients with PSC and IBD.We collected data from European and North American centers participating in the International PSC Study Group from patients with PSC and IBD who received at least 3 doses of vedolizumab (n= 102; median vedolizumab treatment duration, 412 days). Demographic and clinical data were collected from baseline and during the follow-up period (until liver transplantation, death, or 56 days after the final vedolizumab infusion). We analyzed overall changes in biochemical features of liver and proportions of patients with reductions in serum levels of alkaline phosphatase (ALP) of 20% or more, from baseline through last follow-up evaluation. Other endpoints included response of IBD to treatment (improved, unchanged, or worsened, judged by the treating clinician, as well as endoscopic score) and liver-related outcomes.In the entire cohort, the median serum level of ALP increased from 1.54-fold the upper limit of normal at baseline to 1.64-fold the upper limit of normal at the last follow-up examination (P= .018); serum levels of transaminases and bilirubin also increased by a small amount between baseline and the last follow-up examination. Serum levels of ALP decreased by 20% or more in 21 patients (20.6%); only the presence of cirrhosis (odds ratio, 4.48; P= .019) was independently associated with this outcome. Of patients with available endoscopic data, 56.8% had a response of IBD to treatment. Liver-related events occurred in 21 patients (20.6%), including bacterial cholangitis, cirrhosis decompensation, or transplantation.In an analysis of patients with PSC and IBD in an international study group, we found no evidence for a biochemical response to vedolizumab, although serum level of ALP decreased by 20% or more in a subset of patients. Vedolizumab appears to be well tolerated and the overall response of IBD was the same as expected for patients without PSC.
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