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1.
Front Genet ; 13: 872486, 2022.
Article in English | MEDLINE | ID: mdl-35903348

ABSTRACT

Sequencing ancient DNA to high coverage is often limited by sample quality and cost. Imputing missing genotypes can potentially increase information content and quality of ancient data, but requires different computational approaches than modern DNA imputation. Ancient imputation beyond humans has not been investigated. In this study we report results of a systematic evaluation of imputation of three whole genome ancient Sus scrofa samples from the Early and Late Neolithic (∼7,100-4,500 BP), to test the utility of imputation. We show how issues like genetic architecture and, reference panel divergence, composition and size affect imputation accuracy. We evaluate a variety of imputation methods, including Beagle5, GLIMPSE, and Impute5 with varying filters, pipelines, and variant calling methods. We achieved genotype concordance in most cases reaching above 90%; with the highest being 98% with ∼2,000,000 variants recovered using GLIMPSE. Despite this high concordance the sources of diversity present in the genotypes called in the original high coverage genomes were not equally imputed leading to biases in downstream analyses; a trend toward genotypes most common in the reference panel is observed. This demonstrates that the current reference panel does not possess the full diversity needed for accurate imputation of ancient Sus, due to missing variations from Near Eastern and Mesolithic wild boar. Imputation of ancient Sus scrofa holds potential but should be approached with caution due to these biases, and suggests that there is no universal approach for imputation of non-human ancient species.

2.
Scand J Rheumatol ; 51(4): 268-278, 2022 07.
Article in English | MEDLINE | ID: mdl-34474649

ABSTRACT

OBJECTIVES: To compare the effect of treat-to-target-based escalations in conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) and biologics on clinical disease activity and magnetic resonance imaging (MRI) inflammation in a rheumatoid arthritis (RA) cohort in clinical remission. METHOD: One-hundred patients with established RA, Disease Activity Score based on 28-joint count-C-reactive protein (DAS28-CRP) < 3.2, and no swollen joints (hereafter referred to as 'in clinical remission') who received csDMARDs underwent clinical evaluation and MRI of the wrist and second to fifth metacarpophalangeal joints every 4 months. They followed a 2 year MRI treatment strategy targeting DAS28-CRP ≤ 3.2, no swollen joints, and absence of MRI osteitis, with predefined algorithmic treatment escalation: first: increase in csDMARDs; second: adding a biologic; third: switch biologic. MRI osteitis and Health Assessment Questionnaire (HAQ) (co-primary outcomes) and MRI combined inflammation and Simplified Disease Activity Index (SDAI) (key secondary outcomes) were assessed 4 months after treatment change and expressed as estimates of group differences. Statistical analyses were based on the intention-to-treat population analysed using repeated-measures mixed models. RESULTS: Escalation to first biologic compared to csDMARD escalation more effectively reduced MRI osteitis (difference between least squares means 1.8, 95% confidence interval 1.0-2.6), HAQ score (0.08, 0.03-0.1), MRI combined inflammation (2.5, 0.9-4.1), and SDAI scores (2.7, 1.9-3.5). CONCLUSIONS: Treat-to-target-based treatment escalations to biologics compared to escalation in csDMARDs more effectively improved MRI inflammation, physical function, and clinical disease activity in patients with established RA in clinical remission. Treatment escalation in RA patients in clinical remission reduces clinical and MRI-assessed disease activity. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01656278.


Subject(s)
Antirheumatic Agents , Arthritis, Rheumatoid , Biological Products , Osteitis , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/diagnostic imaging , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/pathology , Biological Products/therapeutic use , Edema/drug therapy , Humans , Inflammation/drug therapy , Magnetic Resonance Imaging , Osteitis/diagnostic imaging , Osteitis/drug therapy , Osteitis/etiology , Remission Induction , Severity of Illness Index , Treatment Outcome
4.
Scand J Rheumatol ; 49(3): 200-209, 2020 May.
Article in English | MEDLINE | ID: mdl-31847676

ABSTRACT

Objectives: The Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint (SIJ) scoring system assesses six or five (6/5) semicoronal magnetic resonance imaging (MRI) slices for inflammation/structural lesions in patients with axial spondyloarthritis (axSpA). However, the cartilaginous SIJ compartment may be visible in a few additional slices. The objective was to investigate interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types using an 'all slices' approach versus standard SPARCC scoring of 6/5 slices.Method: Fifty-three axSpA patients were treated with the tumour necrosis factor inhibitor golimumab and followed with serial MRI scans at weeks 0, 4, 16, and 52. The most anterior and posterior slices covering the cartilaginous compartment and the transitional slice were identified. Scores for inflammation, fat metaplasia, erosion, backfill, and ankylosis in the cartilaginous SIJ compartment were calculated for the 'all slices' approach and the 6/5 slices standard.Results: By the 'all slices' approach, three readers scored mean 7.2, 7.7, and 7.0 slices per MRI scan. Baseline and change scores for the various lesion types closely correlated between the two approaches (Pearson's rho ≥ 0.95). Inflammation score was median 13 (interquartile range 6-21, range 0-49) for 6/5 slices versus 14 (interquartile range 6-23, range 0-69) for all slices at baseline. Interreader reliability, sensitivity to change, and classification of MRI scans as positive or negative for various lesion types were similar.Conclusion: The standardized 6/5 slices approach showed no relevant differences from the 'all slices' approach and, therefore, is equally suited for monitoring purposes.


Subject(s)
Sacroiliac Joint/diagnostic imaging , Sacroiliitis/diagnostic imaging , Spondylarthropathies/diagnostic imaging , Adipose Tissue/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Ankylosis/diagnostic imaging , Antibodies, Monoclonal/therapeutic use , Bone Marrow/diagnostic imaging , Cartilage, Articular/diagnostic imaging , Cortical Bone/diagnostic imaging , Edema/diagnostic imaging , Female , Humans , Inflammation , Magnetic Resonance Imaging/methods , Male , Metaplasia , Middle Aged , Observer Variation , Sacroiliitis/drug therapy , Spondylarthropathies/drug therapy , Tumor Necrosis Factor Inhibitors/therapeutic use , Young Adult
5.
Scand J Rheumatol ; 48(3): 185-197, 2019 May.
Article in English | MEDLINE | ID: mdl-30422733

ABSTRACT

OBJECTIVE: To investigate temporal changes in structural progression assessed by serial conventional radiography and magnetic resonance imaging (MRI) of the sacroiliac joints (SIJs) and spine in patients with ankylosing spondylitis (AS) treated with tumour necrosis factor (TNF) inhibitor for 5 years. METHOD: Forty-two patients were included and 33 patients were followed for 5 years in a prospective investigator-initiated study. Conventional radiographs were required four times and MRI seven times. The modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS); Spondyloarthritis Research Consortium of Canada (SPARCC) MRI SIJ and Spine Inflammation, and SPARCC MRI SIJ Structural Score (SSS) for Fat, Erosion, Backfill, and Ankylosis; and the Canada-Denmark MRI scores for Spine Inflammation, Fat, Erosion, and New Bone Formation (NBF) were applied. RESULTS: Compared with baseline, MRI Inflammation had decreased significantly at week 22 (spine)/week 46 (SIJ) and thereafter. MRI SIJ Fat (from week 22), SIJ Ankylosis, Spine NBF, and mSASSS had increased significantly at week 46 and thereafter. SIJ Erosion had decreased from year 2. The annual progression rate in mSASSS was significantly higher during weeks 0-46 compared to week 46 to year 3. In multivariate regression analyses, baseline SIJ Inflammation and Backfill were independent predictors of 5 year progression in SIJ Ankylosis. Spine Erosion predicted progression in Spine NBF. Longitudinally, Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Disease Activity Index, MRI Spine Inflammation, Fat, and Erosion scores were significantly associated with mSASSS. SIJ Inflammation, Fat, Erosion, and Backfill scores were longitudinally associated with SIJ Ankylosis. Structural progression was not associated with body mass index, smoking, or Assessment of SpondyloArthritis international Society Non-Steroidal Anti-Inflammatory Drug Index. CONCLUSION: In a 5 year follow-up study of patients with AS treated with TNF inhibitor, structural progression decreased over time.


Subject(s)
Antirheumatic Agents/therapeutic use , Magnetic Resonance Imaging , Radiography , Sacroiliac Joint , Spondylitis, Ankylosing , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Disease Progression , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Male , Middle Aged , Outcome Assessment, Health Care , Prospective Studies , Radiography/methods , Radiography/statistics & numerical data , Sacroiliac Joint/diagnostic imaging , Sacroiliac Joint/pathology , Severity of Illness Index , Spondylitis, Ankylosing/diagnosis , Spondylitis, Ankylosing/drug therapy , Spondylitis, Ankylosing/physiopathology
6.
Scand J Rheumatol ; 46(5): 353-358, 2017 Sep.
Article in English | MEDLINE | ID: mdl-27682742

ABSTRACT

OBJECTIVES: To investigate the multi-biomarker disease activity (MBDA) score by comparison with imaging findings in an investigator-initiated rheumatoid arthritis (RA) trial (HURRAH trial, NCT00696059). METHOD: Fifty-two patients with established RA initiated adalimumab treatment and had magnetic resonance imaging (MRI), ultrasonography (US), computed tomography (CT), and radiography performed at weeks 0, 26, and 52. Serum samples were analysed using MBDA score assays and associations between clinical measures, MBDA score, and imaging findings were investigated. RESULTS: The MBDA score correlated significantly with MRI synovitis (rho = 0.65, p < 0.001), MRI bone marrow oedema (rho = 0.36, p = 0.044), and US power Doppler (PD) score at week 26 (rho = 0.35, p = 0.039) but not at week 0 or week 52. In the 15 patients who had achieved a Disease Activity Score based on C-reactive protein (DAS28-CRP) < 2.6 at week 26, MRI and/or US detected subclinical inflammation and 13 (87%) had a moderate/high MBDA score. For the cohort with available data, none of the four patients in MBDA remission (score ≤ 25) at week 26 had progression of imaging damage from baseline to week 52 whereas progression was observed in three out of nine (33%) and seven out of 21 (33%) patients with moderate (30-44) and high (> 44) MBDA scores, respectively. CONCLUSIONS: In this cohort, the MBDA score correlated poorly with MRI/US inflammation. However, the MBDA score and MRI/US were generally concordant in showing signs of inflammation in most patients in clinical remission during anti-tumour necrosis factor (anti-TNF) therapy. MBDA scores were elevated in all patients with structural damage progression.


Subject(s)
Adalimumab/therapeutic use , Arthritis, Rheumatoid , Joints , Magnetic Resonance Imaging , Methotrexate/therapeutic use , Tomography, X-Ray Computed , Tumor Necrosis Factor-alpha/blood , Aged , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/epidemiology , Biomarkers/blood , C-Reactive Protein/analysis , Denmark/epidemiology , Disease Progression , Female , Humans , Joints/diagnostic imaging , Joints/pathology , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/statistics & numerical data , Male , Middle Aged , Patient Acuity , Radiography/methods , Radiography/statistics & numerical data , Remission Induction , Research Design/statistics & numerical data , Statistics as Topic , Synovitis/diagnosis , Synovitis/drug therapy , Synovitis/etiology , Tomography, X-Ray Computed/methods , Tomography, X-Ray Computed/statistics & numerical data , Ultrasonography/methods , Ultrasonography/statistics & numerical data
7.
Diabetes Obes Metab ; 18 Suppl 1: 10-22, 2016 09.
Article in English | MEDLINE | ID: mdl-27615127

ABSTRACT

During embryonic development, endocrine cells of the pancreas are specified from multipotent progenitors. The transcription factor Neurogenin 3 (NEUROG3) is critical for this development and it has been shown that all endocrine cells of the pancreas arise from endocrine progenitors expressing NEUROG3. A thorough understanding of the role of NEUROG3 during development, directed differentiation of pluripotent stem cells and in models of cellular reprogramming, will guide future efforts directed at finding novel sources of ß-cells for cell replacement therapies. In this article, we review the expression and function of NEUROG3 in both mouse and human and present the further characterization of a monoclonal antibody directed against NEUROG3. This antibody has been previously been used for detection of both mouse and human NEUROG3. However, our results suggest that the epitope recognized by this antibody is specific to mouse NEUROG3. Thus, we have also generated a monoclonal antibody specifically recognizing human NEUROG3 and present the characterization of this antibody here. Together, these antibodies will provide useful tools for future studies of NEUROG3 expression, and the data presented in this article suggest that recently described expression patterns of NEUROG3 in human foetal and adult pancreas should be re-examined.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , Cell Differentiation/genetics , Gene Expression Regulation, Developmental/genetics , Islets of Langerhans/cytology , Nerve Tissue Proteins/genetics , Animals , Antibodies, Monoclonal , Basic Helix-Loop-Helix Transcription Factors/metabolism , Basic Helix-Loop-Helix Transcription Factors/physiology , Cellular Reprogramming , Glucagon-Secreting Cells/cytology , Glucagon-Secreting Cells/metabolism , Humans , Immunohistochemistry , Insulin-Secreting Cells/cytology , Insulin-Secreting Cells/metabolism , Islets of Langerhans/metabolism , Mice , Nerve Tissue Proteins/metabolism , Nerve Tissue Proteins/physiology , Pancreatic Polypeptide-Secreting Cells/cytology , Pancreatic Polypeptide-Secreting Cells/metabolism , Somatostatin-Secreting Cells/cytology , Somatostatin-Secreting Cells/metabolism
8.
J Anim Sci ; 94(4): 1446-58, 2016 Apr.
Article in English | MEDLINE | ID: mdl-27136004

ABSTRACT

Number of teats (NT) is an important trait affecting both piglet's welfare and the production level of pig farms. Biologically, embryonic mammary gland development requires the coordination of many signaling pathways necessary for the proper development of teats. Several QTL for NT have been identified; however, further analysis is still lacking. Therefore, gene networks derived from genomewide association study (GWAS) results can be used to examine shared pathways and functions of putative candidate genes. Besides, such analyses may also be helpful to understand the genetic diversity between populations for the same trait or traits. In this study, we identified significant SNP for Landrace-based (line C) and Large White-based (line D) dam lines. Besides, gene-transcription factor (TF) networks were constructed aiming to obtain the most likely candidate genes for NT in each line followed by a comparative analysis between both lines to access similarities or dissimilarities at the marker and gene level. We identified 24 and 19 significant SNP (Bayes factor ≥ 100) for lines C and D, respectively. Only 1 significant SNP overlapped both lines. Network analysis illustrated gene interactions consistent with known mammal's breast biology and captured known TF. We observed different sets of putative candidate genes for NT in each line evaluated that may have common effects on the phenotype. Based on these results, we demonstrated the importance of post-GWAS analyses increasing the biological understanding of relevant genes for a complex trait. Moreover, we believe that this genomic diversity across lines should be taken into account, considering breed-specific reference populations for genomic selection.


Subject(s)
Genetic Variation , Genome-Wide Association Study , Mammary Glands, Animal/anatomy & histology , Swine/anatomy & histology , Swine/genetics , Animals , Bayes Theorem , Gene Regulatory Networks , Genomics , Phenotype , Quantitative Trait Loci , Transcription Factors/genetics
9.
Anim Genet ; 45(2): 198-204, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24450499

ABSTRACT

Although structural properties of the porcine reproductive system are shared by many placental mammals, some combination of these properties is unique to pigs. To explore whether genomic elements specific to pigs could potentially underlie this uniqueness, we made the first step to identify novel transcripts in two representative pig reproductive tissues by the technique of massively parallel sequencing. To automate the whole process, we built a computational pipeline, which can also be easily extended for similar studies in other species. In total, 5516 and 9061 novel transcripts were found, and 159 and 252 novel transcripts appear to be specific to pigs for the placenta and testis respectively. Furthermore, these novel transcripts were found to be enriched in quantitative trait loci (QTL) regions for reproduction traits in pigs. We validated eight of these novel transcripts by quantitative real-time PCR. With respect to their genomic organization and their functional relationship to reproduction, these transcripts need to be further validated and explored in various pig breeds to better comprehend the relevant aspects of pig physiology that contribute to reproductive performance.


Subject(s)
Placenta/metabolism , RNA, Messenger/chemistry , Reproduction/genetics , Swine/genetics , Testis/metabolism , Animals , Female , Male , Pregnancy , Quantitative Trait Loci , RNA, Messenger/metabolism , Sequence Analysis, RNA , Species Specificity , Transcriptome
10.
Scand J Rheumatol ; 43(3): 202-8, 2014.
Article in English | MEDLINE | ID: mdl-24354412

ABSTRACT

OBJECTIVES: To investigate the pattern and development of bone erosion and proliferation in patients with psoriatic arthritis (PsA) during treatment with adalimumab, using high-resolution computed tomography (CT) and conventional radiography. METHOD: Forty-one biologic-naïve PsA patients were initiated with adalimumab 40 mg subcutaneously every other week. CT and radiography of the 2nd-5th metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints were conducted at baseline (n = 41) and after 24 weeks (n = 32). Changes in bone erosion and proliferation are described and the imaging modalities compared. RESULTS: Ninety percent of bone erosions detected by CT were located in the metacarpal heads, and most frequently in the 2nd-3rd MCP joints. Radial (37%) and ulnar (31%) surfaces were more frequently eroded than dorsal (10%) and palmar (22%) sites. Using CT, bone proliferations were located primarily on the sides of the distal part of the DIP joints (43% of all proliferations), but also proximally in DIP (17%) and MCP joints (27%). For bone erosions and proliferations, respectively, radiography showed a low sensitivity (17% and 26%), but a high specificity (98% and 95%) and accuracy (93% and 87%), with CT as the gold standard reference. Neither CT nor radiography revealed statistically significant changes in bone erosion or proliferation scores between baseline and follow-up. CONCLUSIONS: Patterns of bone erosion and proliferation in PsA hands were revealed in more detail by CT than by radiography. No overall progression or repair could be detected during adalimumab treatment with either of the methods.


Subject(s)
Antibodies, Monoclonal, Humanized/administration & dosage , Arthritis, Psoriatic/diagnostic imaging , Arthritis, Psoriatic/drug therapy , Metacarpophalangeal Joint/drug effects , Metacarpophalangeal Joint/diagnostic imaging , Tomography, X-Ray Computed/methods , Adalimumab , Adult , Anti-Inflammatory Agents/administration & dosage , Arthritis, Psoriatic/pathology , Bone and Bones/cytology , Bone and Bones/pathology , Cell Proliferation , Cohort Studies , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Injections, Subcutaneous , Longitudinal Studies , Male , Metacarpophalangeal Joint/pathology , Middle Aged , Radiography/methods , Reproducibility of Results , Risk Assessment , Severity of Illness Index , Statistics, Nonparametric , Time Factors , Treatment Outcome
11.
Cell Death Dis ; 4: e523, 2013 Mar 07.
Article in English | MEDLINE | ID: mdl-23470530

ABSTRACT

We previously showed that injury by partial duct ligation (PDL) in adult mouse pancreas activates Neurogenin 3 (Ngn3)(+) progenitor cells that can differentiate to ß cells ex vivo. Here we evaluate the role of Ngn3(+) cells in ß cell expansion in situ. PDL not only induced doubling of the ß cell volume but also increased the total number of islets. ß cells proliferated without extended delay (the so-called 'refractory' period), their proliferation potential was highest in small islets, and 86% of the ß cell expansion was attributable to proliferation of pre-existing ß cells. At sufficiently high Ngn3 expression level, upto 14% of all ß cells and 40% of small islet ß cells derived from non-ß cells. Moreover, ß cell proliferation was blunted by a selective ablation of Ngn3(+) cells but not by conditional knockout of Ngn3 in pre-existing ß cells supporting a key role for Ngn3(+) insulin(-) cells in ß cell proliferation and expansion. We conclude that Ngn3(+) cell-dependent proliferation of pre-existing and newly-formed ß cells as well as reprogramming of non-ß cells contribute to in vivo ß cell expansion in the injured pancreas of adult mice.


Subject(s)
Basic Helix-Loop-Helix Transcription Factors/metabolism , Insulin-Secreting Cells/physiology , Nerve Tissue Proteins/metabolism , Pancreas/metabolism , Animals , Basic Helix-Loop-Helix Transcription Factors/genetics , Cell Proliferation , Cell Size , Insulin/metabolism , Insulin-Secreting Cells/cytology , Male , Mice , Mice, Inbred BALB C , Nerve Tissue Proteins/genetics , Pancreas/injuries , Pancreas/pathology , Regeneration
13.
Diabetologia ; 55(1): 154-65, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21947380

ABSTRACT

AIMS/HYPOTHESIS: The aim of the study was to identify surface bio-markers and corresponding antibody tools that can be used for the imaging and immunoisolation of the pancreatic beta cell and its progenitors. This may prove essential to obtain therapeutic grade human beta cells via stem cell differentiation. METHODS: Using bioinformatics-driven data mining, we generated a gene list encoding putative plasma membrane proteins specifically expressed at distinct stages of the developing pancreas and islet beta cells. In situ hybridisation and immunohistochemistry were used to further prioritise and identify candidates. RESULTS: In the developing pancreas seizure related 6 homologue like (SEZ6L2), low density lipoprotein receptor-related protein 11 (LRP11), dispatched homologue 2 (Drosophila) (DISP2) and solute carrier family 30 (zinc transporter), member 8 (SLC30A8) were found to be expressed in early islet cells, whereas discoidin domain receptor tyrosine kinase 1 (DDR1) and delta/notch-like EGF repeat containing (DNER) were expressed in early pancreatic progenitors. The expression pattern of DDR1 overlaps with the early pancreatic and duodenal homeobox 1 (PDX1)⁺/NK6 homeobox 1 (NKX6-1)⁺ multipotent progenitor cells from embryonic day 11, whereas DNER expression in part overlaps with neurogenin 3 (NEUROG3)⁺ cells. In the adult pancreas SEZ6L2, LRP11, DISP2 and SLC30A8, but also FXYD domain containing ion transport regulator 2 (FXYD2), tetraspanin 7 (TSPAN7) and transmembrane protein 27 (TMEM27), retain an islet-specific expression, whereas DDR1 is undetectable. In contrast, DNER is expressed at low levels in peripheral mouse and human islet cells. Re-expression of DDR1 and upregulation of DNER is observed in duct-ligated pancreas. Antibodies to DNER and DISP2 have been successfully used in cell sorting. CONCLUSIONS/INTERPRETATION: Extracellular epitopes of SEZ6L2, LRP11, DISP2, DDR1 and DNER have been identified as useful tags by applying specific antibodies to visualise pancreatic cell types at specific stages of development. Furthermore, antibodies recognising DISP2 and DNER are suitable for FACS-mediated cell purification.


Subject(s)
Antigens, Surface/metabolism , Cell Separation/methods , Islets of Langerhans/metabolism , Stem Cells/metabolism , Adult , Animals , Biomarkers/metabolism , Cell Line , Computational Biology/methods , Data Mining , Flow Cytometry , Humans , Immunohistochemistry , In Situ Hybridization, Fluorescence , Islets of Langerhans/cytology , Islets of Langerhans/embryology , Mice , Mice, Inbred BALB C , Organ Culture Techniques , Stem Cells/cytology
14.
Diabetologia ; 54(11): 2820-31, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21822931

ABSTRACT

AIMS/HYPOTHESIS: The glucagon gene (GCG) encodes several hormones important for energy metabolism: glucagon, oxyntomodulin and glucagon-like peptide (GLP)-1 and -2. Variants in GCG may associate with type 2 diabetes, obesity and/or related metabolic traits. METHODS: GCG was re-sequenced as a candidate gene in 865 European individuals. Twenty-nine variants were identified. Four variants that were considered to have a likelihood for altered functionality: rs4664447, rs7581952, Ile158Val and Trp169Ter, were genotyped in 17,584 Danes. RESULTS: When examined in 5,760 treatment-naive individuals, homozygous carriers of the low frequency (minor allele frequency 2.3%) G allele of rs4664447, predicted to disrupt an essential splice enhancer binding site, had lower levels of fasting plasma glucose (mean ± SD, 4.8 ± 1.2 vs 5.5 ± 0.8 mmol/l, p = 0.004); fasting serum insulin (22 ± 14 vs 42 ± 27 pmol/l, p = 0.04); glucose-stimulated serum insulin (159 ± 83 vs 290 ± 183 pmol/l, p = 0.01) and adult height (165 ± 10 vs 172 ± 9 cm, p = 0.0009) compared with A allele carriers. During oral glucose tolerance and hyperglycaemic arginine stimulation tests, the plasma AUC for GLP-1 (730 ± 69 vs 1,334 ± 288 pmol/l × min, p = 0.0002) and basal and stimulated levels of serum insulin and plasma glucagon were ∼50% decreased (p < 0.001) among three homozygous carriers compared with nine matched wild-type carriers. rs7581952, Ile158Val and Trp169Ter (where 'Ter' indicates 'termination') variants of GCG did not significantly associate or co-segregate with the metabolic traits examined. CONCLUSIONS/INTERPRETATION: Re-sequencing of GCG revealed a low frequency intronic variant, rs4664447, and follow-up physiological studies suggest that this variant in homozygous form may cause decreased fasting and stimulated levels of insulin, glucagon and GLP-1. Overall, our findings suggest that variation in GCG has no major impact on carbohydrate metabolism in the study populations examined.


Subject(s)
Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/genetics , Glucagon-Like Peptide 1/blood , Glucagon/blood , Glucagon/genetics , Insulin/blood , Polymorphism, Single Nucleotide , Adolescent , Adult , Age of Onset , Aged , Case-Control Studies , Child , Child, Preschool , Czechoslovakia , Denmark , Diabetes Mellitus, Type 2/complications , Europe , Female , Genetic Association Studies , Glucagon-Like Peptide 1/genetics , Homozygote , Humans , Infant , Insulin/metabolism , Insulin Resistance , Insulin Secretion , Male , Middle Aged , Obesity/blood , Obesity/complications , Obesity/genetics
15.
Diabetes Obes Metab ; 13 Suppl 1: 60-8, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21824258

ABSTRACT

We have previously reported severe anorexia abruptly induced in rats 2-3 weeks after they have been transplanted subcutaneously with the glucagonoma MSL-G-AN. Vagotomy did not affect the time of onset and severity of anorexia, and the anorectic state resembles hunger with strongly elevated neuropeptide Y (NPY) mRNA levels in the nucleus arcuatus. We now show that circulating levels of bioactive glucagon-like peptide-1 (GLP-1) (7-36amide) start to increase above control levels exactly at the time of onset of anorexia. At this time-point, bioactive glucagon as well as total glucagon precursors and GLP-1 metabolites are already vastly elevated compared to controls. We further show that intravenous administration of very high concentrations of GLP-1 to hungry schedule-fed rats causes anorexia in a dose-dependent manner, which is blocked by the GLP-1 receptor antagonist exendin (9-39). GLP-1 (7-36amide) has a well-characterized anorectic effect but also causes taste aversion when administered centrally. The anorectic effect is blocked in rats treated neonatally by monosodium glutamate (MSG). We show that MSG treatment does not prevent the MSL-G-AN-induced anorexia, thereby suggesting a different type of anorectic function. We show a very strong component of taste aversion as anorectic rats, when presented to novel or known alternative food items, will resume normal feeding for 1 day, and then redevelop anorexia. We hypothetize that the anorexia in MSL-G-AN tumour-bearing rats correlates with a foetal processing pattern of proglucagon to both glucagon and GLP-1 (7-36amide), and is due to taste aversion. The sudden onset is characterized by a dramatic increase in circulating levels of biologically active GLP-1 (7-36amide), suggesting eventual saturation of proteolytic inactivation of its N-terminus.


Subject(s)
Anorexia/metabolism , Glucagon-Like Peptide 1/blood , Glucagonoma/metabolism , Pancreatic Neoplasms/metabolism , Proglucagon/metabolism , Receptors, Glucagon/antagonists & inhibitors , Taste , Animals , Anorexia/chemically induced , Appetite Regulation/drug effects , Glucagon-Like Peptide 1/adverse effects , Glucagon-Like Peptide-1 Receptor , Glucagonoma/complications , Male , Neoplasm Transplantation , Peptide Fragments/administration & dosage , Rats
17.
Eur J Histochem ; 54(2): e19, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20558340

ABSTRACT

The aim of this study was to characterize two monoclonal antibodies (F6A11 and F109-D12) generated against Pdx1 (pancreatic and duodenal homeobox-1), a homeodomain transcription factor, which is critical for pancreas formation as well as for normal pancreatic beta cell function. For production of monoclonal antibodies, we immunized Robertsonian POSF (RBF)mice with a GST-Pdx1 fusion protein containing a 68-amino acid C-terminal fragment of rat Pdx1. These monoclonal antibodies detect Pdx1 by western blotting and allow immunohistochemical detection of Pdx1 in both mouse and rat tissue. F6A11 and F109-D12 produce IHC staining patterns indistinguishable from that obtained with highly specific polyclonal Pdx1 antisera raised in rabbits and goats, when applied to embryonic or adult mouse pancreatic tissue. In contrast to previously generated polyclonal anti-Pdx1 antisera, we also demonstrate that F6A11 works for intracellular fluorescence activated cell sorting (FACS) staining of Pdx1. By using F6A11, we characterize the induction of Pdx1 in the Doxycycline (DOX) inducible insulinoma cell line INSralphabeta-Pdx1 and follow the reduction of Pdx1 after removing Dox. Finally, we show that induction of exogenous Pdx1 leads to a reduction in endogenous Pdx1 levels, which suggests that a negative feedback loop is involved in maintaining correct levels of Pdx1 in the cell.


Subject(s)
Antibodies, Monoclonal/immunology , Homeodomain Proteins/immunology , Homeodomain Proteins/metabolism , Trans-Activators/immunology , Trans-Activators/metabolism , Animals , Feedback, Physiological , Homeodomain Proteins/isolation & purification , Immunohistochemistry , Mice , Mice, Transgenic , Trans-Activators/isolation & purification
18.
Clin Rheumatol ; 28(8): 1001-3, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19370307

ABSTRACT

We present a case of toxic hepatitis related to infliximab treatment in a 38-year-old woman with rheumatoid arthritis (RA). The patient had previously been treated with different disease-modifying drugs (DMARDs) alone or in combination but had never revealed signs of liver dysfunction. Due to high disease activity, treatment with infliximab (3 mg/kg i.v.) was initiated in combination with methotrexate (MTX) (25 mg/week) and folic acid (5 mg/week). The patient stopped MTX and folic acid on her own initiative after 3 weeks due to improvement of joint symptoms. After seven infusions, progressive elevations of the transaminases up to five times the upper normal limit were noted and treatment with infliximab was terminated. Serological tests for viral and autoimmune hepatitis and for ANA and anti-dsDNA were all negative. Specific infliximab antibodies could not be detected. Ultrasound of the liver was normal. Liver biopsy showed late signs of acute toxic hepatitis without MTX-related fibrosis. This is one the first cases that convincingly demonstrates that infliximab treatment may cause toxic hepatitis. Moreover, the case suggests a lack of hepatic cross-toxicity between infliximab and etanercept as the patient continued with etanercept without new episodes of liver dysfunction.


Subject(s)
Antibodies, Monoclonal/adverse effects , Chemical and Drug Induced Liver Injury/etiology , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adult , Arthritis, Rheumatoid/drug therapy , Chemical and Drug Induced Liver Injury/pathology , Etanercept , Female , Humans , Immunoglobulin G/therapeutic use , Immunologic Factors/therapeutic use , Infliximab , Receptors, Tumor Necrosis Factor/therapeutic use
19.
Ann Rheum Dis ; 68(10): 1585-90, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19019887

ABSTRACT

OBJECTIVE: With computed tomography (CT) and radiography, to investigate if repair of bone erosions, defined as regression of erosion scores, occurs during adalimumab treatment of patients with rheumatoid arthritis (RA). METHODS: Fifty-two patients with RA, naïve to biological agents, with at least two low-grade radiographic erosions in the wrist or metacarpophalangeal (MCP) joints in the same (index) hand, initiated adalimumab 40 mg subcutaneously every other week. Thirty-five patients completed the study (median age 61 years (interquartile range 46-68), disease duration 8 years (3-15)). CT of the index wrist and MCP joints 2-5 and radiographs of hands and forefeet were obtained at baseline, 6 and 12 months. Images were evaluated by investigators blinded to chronology and clinical data, and assessed according to Sharp/van der Heijde (radiographs) and OMERACT RA MRI scoring (CT) methods. RESULTS: Disease activity score, C-reactive protein, tender and swollen joints count and Health Assessment Questionnaire score had all decreased at 6 and 12 months (wilcoxon signed-ranks test p<0.001). No significant change in any imaging parameters of joint destruction was observed at 6 and 12 months. High intrareader agreements were reached (mean intraobserver intraclass coefficients: 0.96 (CT) and 0.97 (radiography)). The number of patients with change scores exceeding the smallest detectable change (SDC) was comparable on CT and radiography, as were the proportions of patients progressing/regressing. Decreased erosion scores at 12 months were registered in 1.6% and 1.8% of sites assessed on CT and radiography, respectively. CONCLUSION: Repair of erosions in adalimumab-treated patients with RA is rare, but erosive regression, exceeding the SDC, on CT and radiography occurred. The very limited overall erosive progression supports the view that joint destruction is minimal during adalimumab treatment of patients with RA.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Adalimumab , Aged , Antibodies, Monoclonal, Humanized , Arthritis, Rheumatoid/diagnostic imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Observer Variation , Tomography, X-Ray Computed
20.
Clin Rheumatol ; 28(1): 35-40, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18726550

ABSTRACT

The Bath ankylosing spondylitis metrology index (BASMI; range 0-10) has gained widespread use in daily clinical practice as an objective measure of spinal stiffness not only in patients with ankylosing spondylitis (AS) but also in patients with other spondylarthropathies (SpA). We examined intra-rater and inter-rater reproducibility of BASMI scoring in 30 Danish patients with SpA (median age 40 years, range 22-56 years) fulfilling the European Spondylarthropathy Study Group criteria, 25 of them satisfying the modified New York Criteria for AS. Measurements were performed twice on two different days (median interval 7 days, range 4-11) by a trained physiotherapist (PT) and by an untrained nurse who had undergone a single 1-h training session with the PT. The median BASMI score obtained by the PT on the two test days was 3.5 (range 1-8) and 3.0 (range 1-8), respectively (NS). Test-retest BASMI scores from the PT were significantly correlated (r(s) = 0.95, p < 0.0001). The 95% likely range for the difference between a patient's BASMI scores from two tests was +/-1.4 corresponding to a minimal detectable difference of +/-2 in the individual patient as the scale consists of intervals of 1. Similar results were achieved by the nurse. BASMI scores obtained by the two raters were significantly inter-correlated (r(s) = 0.95, p < 0.0001). The mean difference between paired BASMI scores obtained by the nurse and the PT on test day 1 was -0.2 with a minimal detectable difference of +/-2. A similar result was found using data from test day 2. In conclusion, a change in BASMI less than 2 may be due solely to expected random measurement error. A single 1-h training session allowed an untrained nurse to obtain BASMI results almost identical to those of an experienced PT.


Subject(s)
Health Personnel/education , Nurses , Physical Therapy Specialty/education , Severity of Illness Index , Spondylitis, Ankylosing/diagnosis , Adult , Education, Nursing , Female , Health Personnel/standards , Humans , Male , Middle Aged , Observer Variation , Physical Therapy Specialty/standards , Predictive Value of Tests , Range of Motion, Articular , Reproducibility of Results , Spondylitis, Ankylosing/physiopathology , Young Adult
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