24 results on '"Sørensen GL"'
Search Results
2. Circadian rhythm and the influence of physical activity on circulating surfactant protein D in rheumatoid arthritis at different stages
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Christensen, Anne Friesgaard, Høgh, Silje Vermedal, Lottenburger, Tine, Sørensen, GL, Tornø, I, Holmskov, U, and Junker, Peter
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- 2010
3. Lifecourse socioeconomic circumstances and multimorbidity among older adults
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Li Yi, Tucker-Seeley Reginald D, Sorensen Glorian, and Subramanian SV
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Many older adults manage multiple chronic conditions (i.e. multimorbidity); and many of these chronic conditions share common risk factors such as low socioeconomic status (SES) in adulthood and low SES across the lifecourse. To better capture socioeconomic condition in childhood, recent research in lifecourse epidemiology has broadened the notion of SES to include the experience of specific hardships. In this study we investigate the association among childhood financial hardship, lifetime earnings, and multimorbidity. Methods Cross-sectional analysis of 7,305 participants age 50 and older from the 2004 Health and Retirement Study (HRS) who also gave permission for their HRS records to be linked to their Social Security Records in the United States. Zero-inflated Poisson regression models were used to simultaneously model the likelihood of the absence of morbidity and the expected number of chronic conditions. Results Childhood financial hardship and lifetime earnings were not associated with the absence of morbidity. However, childhood financial hardship was associated with an 8% higher number of chronic conditions; and, an increase in lifetime earnings, operationalized as average annual earnings during young and middle adulthood, was associated with a 5% lower number of chronic conditions reported. We also found a significant interaction between childhood financial hardship and lifetime earnings on multimorbidity. Conclusions This study shows that childhood financial hardship and lifetime earnings are associated with multimorbidity, but not associated with the absence of morbidity. Lifetime earnings modified the association between childhood financial hardship and multimorbidity suggesting that this association is differentially influential depending on earnings across young and middle adulthood. Further research is needed to elucidate lifecourse socioeconomic pathways associated with the absence of morbidity and the presence of multimorbidity among older adults.
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- 2011
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4. A hazardous substance exposure prevention rating method for intervention needs assessment and effectiveness evaluation: the Small Business Exposure Index
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Sapp Amy L, Sembajwe Grace, Roelofs Cora, Stoddard Anne M, LaMontagne Anthony D, and Sorensen Glorian
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Industrial medicine. Industrial hygiene ,RC963-969 ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Aims This paper describes the refinement and adaptation to small business of a previously developed method for systematically prioritizing needs for intervention on hazardous substance exposures in manufacturing worksites, and evaluating intervention effectiveness. Methods We developed a checklist containing six unique sets of yes/no variables organized in a 2 × 3 matrix of exposure potential versus exposure protection at three levels corresponding to a simplified hierarchy of controls: materials, processes, and human interface. Each of the six sets of indicator variables was reduced to a high/moderate/low rating. Ratings from the matrix were then combined to generate an exposure prevention 'Small Business Exposure Index' (SBEI) Summary score for each area. Reflecting the hierarchy of controls, material factors were weighted highest, followed by process, and then human interface. The checklist administered by an industrial hygienist during walk-through inspection (N = 149 manufacturing processes/areas in 25 small to medium-sized manufacturing worksites). One area or process per manufacturing department was assessed and rated. A second hygienist independently assessed 36 areas to evaluate inter-rater reliability. Results The SBEI Summary scores indicated that exposures were well controlled in the majority of areas assessed (58% with rating of 1 or 2 on a 6-point scale), that there was some room for improvement in roughly one-third of areas (31% of areas rated 3 or 4), and that roughly 10% of the areas assessed were urgently in need of intervention (rated as 5 or 6). Inter-rater reliability of EP ratings was good to excellent (e.g., for SBEI Summary scores, weighted kappa = 0.73, 95% CI 0.52–0.93). Conclusion The SBEI exposure prevention rating method is suitable for use in small/medium enterprises, has good discriminatory power and reliability, offers an inexpensive method for intervention needs assessment and effectiveness evaluation, and complements quantitative exposure assessment with an upstream prevention focus.
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- 2009
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5. Body mass index, physical activity, and dietary behaviors among members of an urban community fitness center: a questionnaire survey
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O'Neil Amy E, Kaphingst Karen M, Sorensen Glorian, Bennett Gary G, Kaphingst Kimberly A, and McInnis Kyle
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Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Development of effective behavioral interventions to promote weight control and physical activity among diverse, underserved populations is a public health priority. Community focused wellness organizations, such as YMCAs, could provide a unique channel with which to reach such populations. This study assessed health behaviors and related characteristics of members of an urban YMCA facility. Methods We surveyed 135 randomly selected members of an urban YMCA facility in Massachusetts to examine self-reported (1) physical activity, (2) dietary behaviors, (3) body mass index, and (4) correlates of behavior change among short-term (i.e., one year or less) and long-term (i.e., more than one year) members. Chi-square tests were used to assess bivariate associations between variables, and multivariate linear regression models were fit to examine correlates of health behaviors and weight status. Results Eighty-nine percent of short-term and 94% of long-term members reported meeting current physical activity recommendations. Only 24% of short-term and 19% of long-term members met fruit and vegetable consumption recommendations, however, and more than half were overweight or obese. Length of membership was not significantly related to weight status, dietary behaviors, or physical activity. Most respondents were interested in changing health behaviors, in the preparation stage of change, and had high levels of self-efficacy to change behaviors. Short-term members had less education (p = 0.02), lower household incomes (p = 0.02), and were less likely to identify as white (p = 0.005) than long-term members. In multivariate models, females had lower BMI than males (p = 0.003) and reported less physical activity (p = 0.008). Physical activity was also inversely associated with age (p = 0.0004) and education (p = 0.02). Conclusion Rates of overweight/obesity and fruit and vegetable consumption suggested that there is a need for a weight control intervention among members of an urban community YMCA. Membership in such a community wellness facility alone might not be sufficient to help members maintain a healthy weight. The data indicate that YMCA members are interested in making changes in their dietary and physical activity behaviors. Targeting newer YMCA members might be an effective way of reaching underserved populations. These data will help inform the development of a weight control intervention tailored to this setting.
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- 2007
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6. Serum MFAP4, a novel potential biomarker for liver cirrhosis screening, correlates with transient elastography in NAFLD patients.
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Kanaan R, Yaghi C, Saade Riachy C, Schlosser A, Hamade A, Holmskov U, Medlej-Hashim M, Sørensen GL, and Jounblat R
- Abstract
Background and Aim: Non-alcoholic fatty liver disease (NAFLD) is the leading cause of chronic liver disease in different countries. Liver fibrosis is considered as the most appropriate predictor of NAFLD-associated outcome. Microfibrillar-associated protein 4 (MFAP4) is a glycoprotein located in the extracellular matrix. Circulatory MFAP4 has been suggested as a noninvasive biomarker for the assessment of hepatitis C virus and alcoholic liver disease associated liver fibrosis. In this study, we aimed to investigate the association between serum MFAP4 and liver fibrosis severity in NAFLD patients., Methods: A case-control study was conducted in which NAFLD patients ( n = 25) and healthy participants ( n = 12) were recruited. Liver fibrosis/cirrhosis was assessed by transient elastography (TE) and biochemical parameters were collected. Serum MFAP4 was measured by sandwich ELISA based on two monoclonal anti-MFAP4 antibodies and calibrated with a standard of recombinant MFAP4., Results: Serum MFAP4 levels increased with fibrosis severity and were highly upregulated in patients with cirrhosis (F4 fibrosis stage). In addition, serum MFAP4 levels positively correlated with TE measurement and showed significant association with the severely advanced fibrotic stage in NAFLD patients, in multiple linear regression analysis following adjustment for age, gender, and body mass index., Conclusion: This study suggests the use of MFAP4 as a potential diagnostic noninvasive biomarker for cirrhosis screening in NAFLD patients., (© 2023 The Authors. JGH Open published by Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)
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- 2023
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7. Generation of novel trimeric fragments of human SP-A and SP-D after recombinant soluble expression in E. coli.
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Watson A, Sørensen GL, Holmskov U, Whitwell HJ, Madsen J, and Clark H
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- Cloning, Molecular, Escherichia coli genetics, Escherichia coli metabolism, Gene Expression, Humans, Models, Molecular, Protein Conformation, Receptors, Cell Surface genetics, Receptors, Cell Surface isolation & purification, Receptors, Immunologic genetics, Receptors, Immunologic isolation & purification, Recombinant Proteins, Structure-Activity Relationship, Protein Multimerization, Receptors, Cell Surface chemistry, Receptors, Cell Surface metabolism, Receptors, Immunologic chemistry, Receptors, Immunologic metabolism
- Abstract
Surfactant treatment for neonatal respiratory distress syndrome has dramatically improved survival of preterm infants. However, this has resulted in a markedly increased incidence of sequelae such as neonatal chronic inflammatory lung disease. The current surfactant preparations in clinical use lack the natural lung defence proteins surfactant proteins (SP)-A and D. These are known to have anti-inflammatory and anti-infective properties essential for maintaining healthy non-inflamed lungs. Supplementation of currently available animal derived surfactant therapeutics with these anti-inflammatory proteins in the first few days of life could prevent the development of inflammatory lung disease in premature babies. However, current systems for production of recombinant versions of SP-A and SP-D require a complex solubilisation and refolding protocol limiting expression at scale for drug development. Using a novel solubility tag, we describe the expression and purification of recombinant fragments of human (rfh) SP-A and SP-D using Escherichia coli without the need for refolding. We obtained a mean (± SD) of 23.3 (± 5.4) mg and 86 mg (± 3.5) per litre yield of rfhSP-A and rfhSP-D, respectively. rfhSP-D was trimeric and 68% bound to a ManNAc-affinity column, giving a final yield of 57.5 mg/litre of highly pure protein, substantially higher than the 3.3 mg/litre obtained through the standard refolding protocol. Further optimisation of this novel lab based method could potentially make rfhSP-A and rfhSP-D production more commercially feasible to enable development of novel therapeutics for the treatment of lung infection and inflammation., Competing Interests: Declaration of Competing Interest A patent has been jointly filed by University of Southampton and Spiber Technologies (WO2017109477A2·2017−06-29) on which Alastair Watson, Jens Madsen and Howard Clark are named inventors. The NT technology was developed and is owned by Spiber Technologies., (Copyright © 2020 The Authors. Published by Elsevier GmbH.. All rights reserved.)
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- 2020
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8. Plasma microfibrillar-associated protein 4 is not prognostic of emphysema progression but is associated with cardiovascular disease history and mortality in COPD patients.
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Johansson SL, Wulf-Johansson H, Schlosser A, Titlestad IL, Miller B, Tal-Singer R, Holmskov U, Vestbo J, and Sørensen GL
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Circulating MFAP4 is a relevant biomarker to identify COPD patients at risk of death and cardiovascular comorbidity after smoking cessation http://ow.ly/6vnL30o8t1g., Competing Interests: Conflict of interest: S.L. Johansson has nothing to disclose. Conflict of interest: H. Wulf-Johansson has nothing to disclose. Conflict of interest: A. Schlosser is an inventor of US Patent No. 9,988,442 and EP17199552.5 owned by University of Southern Denmark. Conflict of interest: I.L. Titlestad has nothing to disclose. Conflict of interest: B. Miller is an employee and shareholder of GSK. Conflict of interest: R. Tal-Singer is an employee and shareholder of GSK. Conflict of interest: U. Holmskov is an inventor of US Patent No. 9,988,442 and EP17199552.5 owned by University of Southern Denmark. Conflict of interest: J. Vestbo reports consultancy fees for COPD Phase 2 and 3 programmes and payment for lectures including service in speaker bureaus from GlaxoSmithKline, Chiesi Pharmaceuticals, Boehringer-Ingelheim, Novartis and AstraZeneca, and an unconditional grant for biomarker research at Manchester University Hospital NHS Foundation Trust from Boehringer Ingelheim, outside the submitted work. Conflict of interest: G.L. Sørensen is an inventor of US Patent No. 9,988,442 and EP17199552.5 owned by University of Southern Denmark.
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- 2019
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9. Type I and III collagen turnover is increased in axial spondyloarthritis and psoriatic arthritis. Associations with disease activity and diagnostic capacity.
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Gudmann NS, Siebuhr AS, Christensen AF, Ejstrup L, Sørensen GL, Loft AG, Karsdal MA, Bay-Jensen AC, Munk HL, and Junker P
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- Adult, Area Under Curve, Arthritis, Psoriatic genetics, Case-Control Studies, Enzyme-Linked Immunosorbent Assay, Female, HLA-B27 Antigen genetics, Humans, Male, ROC Curve, Radioimmunoassay, Severity of Illness Index, Spondylarthropathies genetics, Spondylarthropathies metabolism, Arthritis, Psoriatic metabolism, Collagen Type I metabolism, Collagen Type III metabolism, Peptides metabolism
- Abstract
Objectives: To investigate the turnover of type I and III collagen by neo-epitope markers in patients with axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA)., Methods: Patients with PsA (n=101) or axSpA (n=110) and healthy subjects (n=120) were included. Demographic and clinical data were recorded. Markers of type I and III collagen were quantified by RIA (ICTP) or ELISA (C1M and C3M). Non-parametric statistics were applied for intergroup comparisons and correlation studies. The diagnostic potential of these marker molecules was assessed by ROC analysis., Results: C1M and C3M, which originate from soft connective tissues, were significantly higher in axSpA and PsA as compared with healthy control subjects. CIM and C3M correlated with ASDAS and DAS28. Overall, ICTP, which arises from bone degradation, did not differ between disease versus healthy. However, ICTP was lower in HLA-B27 positive than in HLA-B27 negative patients with axSpA. There was no association between bone and soft connective tissue collagen I markers (ICTP and C1M), while C1M and C3M were highly correlated (p<0.0001). C1M discriminated between healthy and diseased with AUCs of 0.83 for PsA and 0.79 for axSpA. C3M AUCs were 0.77 for PsA and 0.78 for axSpA., Conclusions: Type I and III collagen remodelling in soft connective tissue is increased in axSpA and PsA and associates with disease activity. Bone collagen degradation is lower in HLA-B27 positive compared with HLA-B27 negative axSpA, which may represent an aspect of enhanced enthesopathic bone proliferation in HLA-B27 carriers. C1M and C3M distinguish well between healthy and diseased individuals.
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- 2017
10. Alterations of the murine gut microbiome in allergic airway disease are independent of surfactant protein D.
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Barfod KK, Roggenbuck M, Al-Shuweli S, Fakih D, Sørensen SJ, and Sørensen GL
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Background: SP-D is an important host defense lectin in innate immunity and SP-D deficient mice show several abnormal immune effects and are susceptible to allergen-induced airway disease. At the same time, host microbiome interactions play an important role in the development of allergic airway disease, and alterations to gut microbiota have been linked to airway disease through the gut-lung axis. Currently, it is unknown if the genotype ( Sftpd-/- or Sftpd+/+ ) of the standard SP-D mouse model can affect the host microbiota to such an degree that it would overcome the cohousing effect on microbiota and interfere with the interpretation of immunological data from the model. Generally, little is known about the effect of the SP-D protein in itself and in combination with airway disease on the microbiota. In this study, we tested the hypothesis that microbiome composition would change with the lack of SP-D protein and presence of allergic airway disease in the widely used SP-D-deficient mouse model., Results: We describe here for the first time the lung and gut microbiota of the SP-D mouse model with OVA induced allergic airway disease. After the challenge animals were killed and fecal samples were taken from the caecum and lungs were subjected to bronchoalveolar lavage for comparison of gut and lung microbiota by Illumina 16S rRNA gene sequencing. A significant community shift was observed in gut microbiota after challenge with OVA. However, the microbial communities were not significantly different between SP-D deficient and wild type mice from the same cages in either naïve or OVA treated animals. Wild type animals did however show the largest variation between mice., Conclusions: Our results show that the composition of the microbiota is not influenced by the SP-D deficient genotype under naïve or OVA induced airway disease. However, OVA sensitization and pulmonary challenge did alter the gut microbiota, supporting a bidirectional lung-gut crosstalk. Future mechanistic investigations of the influence of induced allergic airway disease on gut microbiota are warranted.
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- 2017
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11. Assessing the Effects of Fibrosis on Lung Function by Light Microscopy-Coupled Stereology.
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Pilecki B and Sørensen GL
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- Algorithms, Animals, Imaging, Three-Dimensional, Models, Anatomic, Organ Size, Pulmonary Fibrosis diagnosis, Respiratory Function Tests, Lung pathology, Lung physiopathology, Microscopy methods, Pulmonary Fibrosis pathology, Pulmonary Fibrosis physiopathology
- Abstract
Pulmonary diseases such as fibrosis are characterized by structural abnormalities that lead to impairment of proper lung function. Stereological analysis of serial tissue sections allows detection and quantitation of subtle changes in lung architecture. Here, we describe a stereology-based method of assessing pathology-induced changes in lung structure.
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- 2017
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12. Chondrocyte activity is increased in psoriatic arthritis and axial spondyloarthritis.
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Gudmann NS, Munk HL, Christensen AF, Ejstrup L, Sørensen GL, Loft AG, Karsdal MA, Bay-Jensen AC, He Y, Siebuhr AS, and Junker P
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- Adult, Area Under Curve, Arthritis, Psoriatic metabolism, Biomarkers blood, Cartilage, Articular metabolism, Cartilage, Articular pathology, Chondrocytes metabolism, Collagen Type II analysis, Collagen Type X analysis, Enzyme-Linked Immunosorbent Assay, Female, Humans, Male, ROC Curve, Sensitivity and Specificity, Spondylarthritis metabolism, Arthritis, Psoriatic pathology, Chondrocytes pathology, Collagen Type II blood, Collagen Type X blood, Spondylarthritis pathology
- Abstract
Background: Psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) are chronic inflammatory rheumatic diseases with complex origins. Both are characterized by altered extracellular matrix remodeling in joints and entheses that results in destructive and osteochondral proliferative lesions. There is a need for biomarkers reflecting core disease pathways for diagnosis and disease mapping. Pro-C2 reflects mature cartilage collagen type IIB formation, while C-Col10 represents turnover of type X collagen, which is exclusively expressed by hypertrophic chondrocytes. The objectives of this study were to study cartilage metabolism in axSpA and PsA by assessing Pro-C2 and C-Col10 and to evaluate their diagnostic utility against a healthy reference population., Methods: Patients with PsA (n = 101) or axSpA (n = 110) were recruited consecutively from three rheumatology outpatient clinics. Demographic and clinical disease measures were recorded. Pro-C2 and C-Col10 were quantified in serum by using newly developed and specific competitive enzyme-linked immunosorbent assays based on monoclonal antibodies. One-way analysis of variance and Tukey's multiple comparison tests were performed on log-transformed data. ROC curve analysis was carried out to evaluate their discriminative power., Results: Pro-C2 levels in serum were significantly increased in both axSpA (median concentration 1.11 ng/ml, 0.67-1.64) and PsA (median concentration 1.03 ng/ml, 0.53-1.47) compared with healthy controls (median concentration 0.30 ng/ml, 0.16-0.41) (p < 0.0001). Pro-C2 did not differ according to treatment. C-Col10 was slightly but equally elevated in the PsA and axSpA groups vs. the control group, but it was significantly lower in patients with axSpA undergoing tumor necrosis factor-α inhibitor (TNFi) treatment. ROC curve analysis revealed AUCs of 0.85 (95 % CI 0.79-0.89) for axSpA and 0.81 (95 % CI 0.75-0.86) for PsA., Conclusions: These findings indicate that cartilage collagen metabolism was enhanced in the axSpA and PsA groups compared with the healthy control group. The lower C-Col10 level in patients with axSpA undergoing TNFi treatment may reflect that hypertrophic chondrocytes in axSpA are targeted by TNFi. ROC curve analysis showed a diagnostic potential for Pro-C2 in axSpA and PsA.
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- 2016
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13. Sleep-wake transition in narcolepsy and healthy controls using a support vector machine.
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Jensen JB, Sorensen HB, Kempfner J, Sørensen GL, Knudsen S, and Jennum P
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- Adult, Algorithms, Area Under Curve, Denmark, Electroencephalography, Electromyography, Female, Humans, Male, Middle Aged, Polysomnography, Reproducibility of Results, Young Adult, Brain Waves physiology, Narcolepsy physiopathology, Sleep physiology, Support Vector Machine, Wakefulness physiology
- Abstract
Narcolepsy is characterized by abnormal sleep-wake regulation, causing sleep episodes during the day and nocturnal sleep disruptions. The transitions between sleep and wakefulness can be identified by manual scorings of a polysomnographic recording. The aim of this study was to develop an automatic classifier capable of separating sleep epochs from epochs of wakefulness by using EEG measurements from one channel. Features from frequency bands α (0-4 Hz), β (4-8 Hz), δ (8-12 Hz), θ (12-16 Hz), 16 to 24 Hz, 24 to 32 Hz, 32 to 40 Hz, and 40 to 48 Hz were extracted from data by use of a wavelet packet transformation and were given as input to a support vector machine classifier. The classification algorithm was assessed by hold-out validation and 10-fold cross-validation. The data used to validate the classifier were derived from polysomnographic recordings of 47 narcoleptic patients (33 with cataplexy and 14 without cataplexy) and 15 healthy controls. Compared with manual scorings, an accuracy of 90% was achieved in the hold-out validation, and the area under the receiver operating characteristic curve was 95%. Sensitivity and specificity were 90% and 88%, respectively. The 10-fold cross-validation procedure yielded an accuracy of 88%, an area under the receiver operating characteristic curve of 92%, a sensitivity of 87%, and a specificity of 87%. Narcolepsy with cataplexy patients experienced significantly more sleep-wake transitions during night than did narcolepsy without cataplexy patients (P = 0.0199) and healthy subjects (P = 0.0265). In addition, the sleep-wake transitions were elevated in hypocretin-deficient patients. It is concluded that the classifier shows high validity for identifying the sleep-wake transition. Narcolepsy with cataplexy patients have more sleep-wake transitions during night, suggesting instability in the sleep-wake regulatory system.
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- 2014
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14. Enzyme-linked immunosorbent assay characterization of basal variation and heritability of systemic microfibrillar-associated protein 4.
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Sækmose SG, Schlosser A, Holst R, Johansson SL, Wulf-Johansson H, Tornøe I, Vestbo J, Kyvik KO, Barington T, Holmskov U, and Sørensen GL
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- Adolescent, Adult, Age Factors, Aged, Antibodies, Monoclonal biosynthesis, Antibodies, Monoclonal immunology, Antibody Specificity immunology, Biomarkers blood, Carrier Proteins immunology, Cross Reactions immunology, Epitope Mapping, Extracellular Matrix Proteins immunology, Female, Glycoproteins immunology, Humans, Liver Cirrhosis blood, Male, Middle Aged, Recombinant Fusion Proteins immunology, Reference Values, Reproducibility of Results, Species Specificity, Twins, Waist-Hip Ratio, Young Adult, Carrier Proteins blood, Enzyme-Linked Immunosorbent Assay, Extracellular Matrix Proteins blood, Glycoproteins blood
- Abstract
Background: Microfibrillar-associated protein 4 (MFAP4) is a systemic biomarker that is significantly elevated in samples from patients suffering from hepatic cirrhosis. The protein is generally localized to elastic fibers and other connective tissue fibers in the extracellular matrix (ECM), and variation in systemic MFAP4 (sMFAP4) has the potential to reflect diverse diseases with increased ECM turnover. Here, we aimed to validate an enzyme-linked immunosorbent assay (ELISA) for the measurement of sMFAP4 with an emphasis on the robustness of the assay. Moreover, we aimed to determine confounders influencing the basal sMFAP4 variability and the genetic contribution to the basal variation., Methods: The sandwich ELISA was based on two monoclonal anti-MFAP4 antibodies and was optimized and calibrated with a standard of recombinant MFAP4. The importance of pre-analytical sample handling was evaluated regarding sample tube type, time, and temperature conditions. The mean value structure and variance structure was determined in a twin cohort including 1,417 Danish twins (age 18-67 years) by mixed-effect linear regression modeling., Results: The practical working range of the sandwich ELISA was estimated to be 4-75 U/ml. The maximum intra- and inter-assay variation was estimated to be 8.7% and 6.6%, respectively. Sample handling and processing appeared to influence MFAP4 measurements only marginally. The average concentration of sMFAP4 in the serum was 18.9 ± 8.4 (SD) U/ml in the twin cohort (95% CI: 18.5-19.4, median sMFAP4 17.3 U/ml). The mean structure model was demonstrated to include waist-hip ratio, age, and cigarette smoking status in interactions with gender. A relatively low heritability of h(2) = 0.24 was found after applying a model including additive genetic factors and shared and non-shared environmental factors., Conclusions: The described ELISA provides robust measures of the liver fibrosis marker sMFAP4. The low heritability and the relatively limited basal variation suggest that increased sMFAP4 reflects disease-induced processes.
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- 2013
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15. M-ficolin binds selectively to the capsular polysaccharides of Streptococcus pneumoniae serotypes 19B and 19C and of a Streptococcus mitis strain.
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Kjaer TR, Hansen AG, Sørensen UB, Holm AT, Sørensen GL, Jensenius JC, and Thiel S
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- Animals, Bacterial Capsules drug effects, Bacterial Capsules immunology, CHO Cells, Complement C4 immunology, Complement C4 metabolism, Cricetinae, Fibrinogen immunology, Fibrinogen metabolism, Hexosamines pharmacology, Humans, Lectins immunology, Ligands, Mannose-Binding Protein-Associated Serine Proteases immunology, Mannose-Binding Protein-Associated Serine Proteases metabolism, Polysaccharides immunology, Protein Binding, Streptococcus mitis immunology, Streptococcus pneumoniae immunology, Ficolins, Bacterial Capsules metabolism, Lectins metabolism, Polysaccharides metabolism, Streptococcus mitis metabolism, Streptococcus pneumoniae metabolism
- Abstract
The three human ficolins (H-, L-, and M-ficolins) and mannan-binding lectin are pattern recognition molecules of the innate immune system mediating activation of the lectin pathway of the complement system. These four human proteins bind to some microorganisms and may be involved in the resolution of infections. We investigated binding selectivity by examining the binding of M-ficolin to a panel of more than 100 different streptococcal strains (Streptococcus pneumoniae and Streptococcus mitis), each expressing distinct polysaccharide structures. M-ficolin binding was observed for three strains only: strains of the pneumococcal serotypes 19B and 19C and a single S. mitis strain expressing a similar polysaccharide structure. The bound M-ficolin, in association with MASP-2, mediated the cleavage of complement factor C4. Binding to the bacteria was inhibitable by N-acetylglucosamine, indicating that the interaction with the bacterial surface takes place via the fibrinogen-like domain. The common N-acetylmannosamine residue present in the structures of the four capsular polysaccharides of group 19 is linked via a phosphodiester bond. This residue is apparently not a ligand for M-ficolin, since the lectin binds to two of the group 19 polysaccharides only. M-ficolin bound strongly to serotype 19B and 19C polysaccharides. In contrast to those of serotypes 19A and 19F, serotype 19B and 19C polysaccharides contain an extra N-acetylmannosamine residue linked via glycoside linkage only. Thus, this extra residue seems to be the M-ficolin ligand. In conclusion, we were able to demonstrate specific binding of M-ficolin to some capsular polysaccharides of the opportunistic pathogen S. pneumoniae and of the commensal bacterium S. mitis.
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- 2013
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16. Surfactant protein d deficiency in mice is associated with hyperphagia, altered fat deposition, insulin resistance, and increased basal endotoxemia.
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Stidsen JV, Khorooshi R, Rahbek MK, Kirketerp-Møller KL, Hansen PB, Bie P, Kejling K, Mandrup S, Hawgood S, Nielsen O, Nielsen CH, Owens T, Holmskov U, and Sørensen GL
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- Animals, Blood Glucose, Central Nervous System drug effects, Endotoxemia genetics, Fatty Acids, Nonesterified blood, Hyperphagia genetics, Hyperphagia metabolism, Immunity, Innate drug effects, Insulin blood, Insulin Resistance genetics, Leptin blood, Mice, Pulmonary Surfactant-Associated Protein D administration & dosage, Pulmonary Surfactant-Associated Protein D deficiency, Adipose Tissue metabolism, Energy Metabolism genetics, Lung metabolism, Pulmonary Surfactant-Associated Protein D genetics, Pulmonary Surfactant-Associated Protein D metabolism
- Abstract
Pulmonary surfactant protein D (SP-D) is a host defence lectin of the innate immune system that enhances clearance of pathogens and modulates inflammatory responses. Recently it has been found that systemic SP-D is associated with metabolic disturbances and that SP-D deficient mice are mildly obese. However, the mechanism behind SP-D's role in energy metabolism is not known.Here we report that SP-D deficient mice had significantly higher ad libitum energy intake compared to wild-type mice and unchanged energy expenditure. This resulted in accumulation but also redistribution of fat tissue. Blood pressure was unchanged. The change in energy intake was unrelated to the basal levels of hypothalamic Pro-opiomelanocortin (POMC) and Agouti-related peptide (AgRP) gene expression. Neither short time systemic, nor intracereberoventricular SP-D treatment altered the hypothalamic signalling or body weight accumulation.In ad libitum fed animals, serum leptin, insulin, and glucose were significantly increased in mice deficient in SP-D, and indicative of insulin resistance. However, restricted diets eliminated all metabolic differences except the distribution of body fat. SP-D deficiency was further associated with elevated levels of systemic bacterial lipopolysaccharide.In conclusion, our findings suggest that lack of SP-D mediates modulation of food intake not directly involving hypothalamic regulatory pathways. The resulting accumulation of adipose tissue was associated with insulin resistance. The data suggest SP-D as a regulator of energy intake and body composition and an inhibitor of metabolic endotoxemia. SP-D may play a causal role at the crossroads of inflammation, obesity, and insulin resistance.
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- 2012
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17. Circadian rhythm and the influence of physical activity on circulating surfactant protein D in early and long-standing rheumatoid arthritis.
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Christensen AF, Hoegh SV, Lottenburger T, Holmskov U, Tornoe I, Hørslev-Petersen K, Sørensen GL, and Junker P
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- Adult, Aged, Female, Humans, Male, Middle Aged, Arthritis, Rheumatoid blood, Arthritis, Rheumatoid physiopathology, Circadian Rhythm physiology, Motor Activity physiology, Pulmonary Surfactant-Associated Protein D blood
- Abstract
Surfactant protein D (SP-D) belongs to the collectin family and has pro-and anti-inflammatory capacities depending on its oligomerization. Previously, circulating SP-D was shown to be decreased in early rheumatoid arthritis (RA) and negatively correlated to disease activity. This study aimed at assessing the diurnal rhythmicity and the influence of physical activity on circulating SP-D in patients with RA at different stages compared with healthy individuals. Patients with early RA (ERA) with disease duration <6 months and with long-standing RA (LRA) with disease duration 5-15 years were included in two sub-studies. Healthy individuals served as controls. Diurnal variation: blood samples were collected every 3 h from 7 a.m to 10 p.m and the following morning. Physical activity: blood sampling was done before and after standardized physical challenge. SP-D was measured by ELISA. SP-D exhibited diurnal variation in healthy controls (n = 15) and in patients with ERA (n = 9) and LRA (n = 9) with peak values at 10 a.m. and nadir in the evening (controls: P < 0.001, ERA: P = 0.004 and LRA: P = 0.009). Three hours after cessation of physical activity, SP-D decreased below pre-exercise levels in both ERA (n = 10), LRA (n = 10) and controls (n = 13) (ERA: P < 0.001, LRA: P < 0.001 and controls: P = 0.005). In patients with RA, the decline was already observed 1 h post-exercise. Circulating SP-D exhibits diurnal variation both in patients with RA at different stages and in healthy controls. SP-D in serum decreases following physical activity in health and RA disease. This study underscores the need of standardized blood sampling conditions in future studies on SP-D.
- Published
- 2011
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- View/download PDF
18. Regulation of pancreatic islet gene expression in mouse islets by pregnancy.
- Author
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Layden BT, Durai V, Newman MV, Marinelarena AM, Ahn CW, Feng G, Lin S, Zhang X, Kaufman DB, Jafari N, Sørensen GL, and Lowe WL Jr
- Subjects
- Animals, Cytokines genetics, Female, Insulin Resistance physiology, Mice, Pregnancy, Pulmonary Surfactant-Associated Protein D genetics, RNA, Messenger biosynthesis, Receptor, Cholecystokinin A genetics, Receptors, Cell Surface genetics, Receptors, G-Protein-Coupled genetics, Gene Expression Regulation, Insulin-Secreting Cells metabolism
- Abstract
Pancreatic β cells adapt to pregnancy-induced insulin resistance by unclear mechanisms. This study sought to identify genes involved in β cell adaptation during pregnancy. To examine changes in global RNA expression during pregnancy, murine islets were isolated at a time point of increased β cell proliferation (E13.5), and RNA levels were determined by two different assays (global gene expression array and G-protein-coupled receptor (GPCR) array). Follow-up studies confirmed the findings for select genes. Differential expression of 110 genes was identified and follow-up studies confirmed the changes in select genes at both the RNA and protein level. Surfactant protein D (SP-D) mRNA and protein levels exhibited large increases, which were confirmed in murine islets. Cytokine-induced expression of SP-D in islets was also demonstrated, suggesting a possible role as an anti-inflammatory molecule. Complementing these studies, an expression array was performed to define pregnancy-induced changes in expression of GPCRs that are known to impact islet cell function and proliferation. This assay, the results of which were confirmed using real-time reverse transcription-PCR assays, demonstrated that free fatty acid receptor 2 and cholecystokinin receptor A mRNA levels were increased at E13.5. This study has identified multiple novel targets that may be important for the adaptation of islets to pregnancy.
- Published
- 2010
- Full Text
- View/download PDF
19. Serum-surfactant SP-D correlates inversely to lung function in cystic fibrosis.
- Author
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Olesen HV, Holmskov U, Schiøtz PO, and Sørensen GL
- Subjects
- Adolescent, Adult, Aged, Biomarkers blood, Case-Control Studies, Child, Female, Forced Expiratory Volume, Humans, Leukocyte Count, Male, Middle Aged, Polymorphism, Single Nucleotide, Pulmonary Surfactant-Associated Protein D genetics, Young Adult, Cystic Fibrosis blood, Cystic Fibrosis physiopathology, Pulmonary Surfactant-Associated Protein D blood
- Abstract
Background: Cystic fibrosis (CF) affects the lungs causing infections and inflammation. Surfactant protein D (SP-D) is an innate defense lectin primarily secreted in the lungs. We investigated the influence of the SP-D Met11Thr polymorphism on CF lung function; and serum SP-D as a marker for CF lung disease., Methods: For 107 CF patients (73 children, and 34 adults) serum SP-D and SP-D Met11Thr genotype were available. Leukocyte count was obtained for a subset of patients. Lung function was measured as forced expiratory volume in one second (FEV-1)., Results: Serum SP-D was increased in CF patients compared to healthy controls, positively correlated to leukocyte count, and negatively correlated to FEV-1. We found no correlation between SP-D Met11Thr genotype and FEV-1, and we found corresponding genotype frequencies in CF patients and in healthy controls., Conclusion: Serum SP-D in CF patients was increased in parallel with leukocyte count and with reduced FEV-1 and may constitute an alternative biomarker for lung disease, in the clinical setting and in research., (Copyright 2010 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
20. Circulating surfactant protein -D is low and correlates negatively with systemic inflammation in early, untreated rheumatoid arthritis.
- Author
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Christensen AF, Sørensen GL, Hørslev-Petersen K, Holmskov U, Lindegaard HM, Junker K, Hetland ML, Stengaard-Pedersen K, Jacobsen S, Lottenburger T, Ellingsen T, Andersen LS, Hansen I, Skjødt H, Pedersen JK, Lauridsen UB, Svendsen A, Tarp U, Pødenphant J, Vestergaard A, Jurik AG, Østergaard M, and Junker P
- Subjects
- Adolescent, Adult, Aged, Arthritis, Rheumatoid genetics, Arthritis, Rheumatoid physiopathology, Arthrography, Female, Genotype, Health Status, Humans, Male, Metallothionein genetics, Middle Aged, Polymorphism, Single Nucleotide, Prospective Studies, Reference Values, Surveys and Questionnaires, Young Adult, Arthritis, Rheumatoid blood, Pulmonary Surfactant-Associated Protein D blood
- Abstract
Introduction: Surfactant protein D (SP-D) is a collectin with immuno-regulatory functions, which may depend on oligomerization. Anti-microbial and anti-inflammatory properties have been attributed to multimeric SP-D variants, while trimeric subunits per se have been suggested to enhance inflammation. Previously, we reported low circulating SP-D in early rheumatoid arthritis (RA), and the present investigation aims to extend these data by serial SP-D serum measurements, studies on synovial fluid, SP-D size distribution and genotyping in patients with early RA., Methods: One-hundred-and-sixty disease-modifying antirheumatic drug (DMARD) naïve RA patients with disease duration less than six months were studied prospectively for four years (CIMESTRA (Ciclosporine, Methotrexate, Steroid in RA) trial) including disease activity measures (C-reactive protein, joint counts and Health Assessment Questionnaire (HAQ) score), autoantibodies, x-ray findings and SP-D. SP-D was quantified by enzyme-linked immunosorbent assay (ELISA) and molecular size distribution was assessed by gel filtration chromatography. Further, SP-D Met11Thr single nucleotide polymorphism (SNP) analysis was performed., Results: Serum SP-D was significantly lower in RA patients at baseline compared with healthy controls (P < 0.001). SP-D increased slightly during follow-up (P < 0.001), but was still subnormal at four years after adjustment for confounders (P < 0.001). SP-D in synovial fluid was up to 2.5-fold lower than in serum. While multimeric variants were detected in serum, SP-D in synovial fluid comprised trimeric subunits only. There were no significant associations between genotype distribution and SP-D. Baseline SP-D was inversely associated to CRP and HAQ score. A similar relationship was observed regarding temporal changes in SP-D and CRP (zero to four years). SP-D was not associated to x-ray findings., Conclusions: This study confirms that circulating SP-D is persistently subnormal in early and untreated RA despite a favourable therapeutic response obtained during four years of follow-up. SP-D correlated negatively to disease activity measures, but was not correlated with x-ray progression or SP-D genotype. These observations suggest that SP-D is implicated in RA pathogenesis at the protein level. The exclusive presence of trimeric SP-D in affected joints may contribute to the maintenance of joint inflammation., Trial Registration: (j.nr NCT00209859).
- Published
- 2010
- Full Text
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21. The presence and activity of SP-D in porcine coronary endothelial cells depend on Akt/PI3K, Erk and nitric oxide and decrease after multiple passaging.
- Author
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Lee MY, Sørensen GL, Holmskov U, and Vanhoutte PM
- Subjects
- Animals, Cells, Cultured, Coronary Vessels cytology, Coronary Vessels metabolism, Culture Techniques, Endothelium, Vascular cytology, Gene Expression Regulation, Nitric Oxide Synthase Type III metabolism, Protein Isoforms metabolism, Pulmonary Surfactant-Associated Protein D genetics, Swine, Tumor Necrosis Factor-alpha metabolism, Endothelial Cells metabolism, Endothelium, Vascular metabolism, Extracellular Signal-Regulated MAP Kinases metabolism, Nitric Oxide metabolism, Proto-Oncogene Proteins c-akt metabolism, Pulmonary Surfactant-Associated Protein D physiology
- Abstract
Surfactant protein D (SP-D) mediates clearance of microorganisms and modulates inflammation in response to cytotoxic stimulation. It is present in various epithelia, but also in vascular smooth muscle and endothelial cells. Experiments were designed to determine whether or not SP-D is present in porcine coronary arterial endothelial cells and if so, to investigate the molecular mechanisms underlying this presence. The expression of SP-D, NO synthase, Akt 1/2 and Erk 1/2 proteins was determined in cultures at passages 1 (#1) and 4 (#4). SP-D in primary cells existed in three isoforms (37-38 kDa and 50 kDa). The 37-38 kDa SP-D forms were the dominant isoforms in the porcine endothelium and were prominent at #1 but partially lost at #4. Tumor necrosis factor-alpha (TNF-alpha) significantly augmented the level of SP-D expression at #1 but not at #4. The basal level of 37-38 kDa SP-D isoforms at #1 was reduced by L-NAME, wortmannin and PD 98059. The low basal expression at #4 could be increased by DETA NONOate (donor of NO) or insulin (activator of PI(3)K/Akt). The presence of nitric oxide synthase was reduced while that of Akt 1/2 and Erk 1/2 was increased at #4. In cells both at passages 1 and 4, TNF-alpha downregulated NO synthase and up-regulated p-Erk 1/2 protein. The present findings demonstrate the presence of SP-D in endothelial cells which is NO-, PI(3)K/Akt- and Erk-dependent. They suggest a protective role of SP-D in these cells.
- Published
- 2009
- Full Text
- View/download PDF
22. Genetic and environmental influences of surfactant protein D serum levels.
- Author
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Sørensen GL, Hjelmborg Jv, Kyvik KO, Fenger M, Høj A, Bendixen C, Sørensen TI, and Holmskov U
- Subjects
- Adolescent, Adult, Aged, Child, Environment, Genetic Variation, Humans, Metabolic Syndrome blood, Metabolic Syndrome genetics, Middle Aged, Polymorphism, Single Nucleotide, Registries, Twins, Pulmonary Surfactant-Associated Protein D blood, Pulmonary Surfactant-Associated Protein D genetics
- Abstract
The collectin surfactant protein D (SP-D) is an important component of the pulmonary innate immune system, but SP-D is also present on extrapulmonary epithelial surfaces and in serum, where it has been used as a biomarker for pulmonary disease states. In this study, we investigate the mechanisms defining the constitutional serum level of SP-D and determine the magnitude of the genetic contribution to serum SP-D in the adult population. Recent studies have demonstrated that serum SP-D concentrations in children are genetically determined and that a single nucleotide polymorphism (SNP) located in the NH(2)-terminal region (Met11Thr) of the mature protein is significantly associated with the serum SP-D levels. A classic twin study was performed on a twin population including 1,476 self-reported healthy adults. The serum SP-D levels increased with male sex, age, and smoking status. The intraclass correlation was significantly higher for monozygotic (MZ) twin pairs than for dizygotic (DZ) twin pairs. Serum SP-D variance was influenced by nonshared environmental effects and additive genetic effects. Multivariate analysis of MZ and DZ covariance matrixes showed significant genetic correlation among serum SP-D and metabolic variables. The Met11Thr variant explained a significant part of the heritability indicating that serum SP-D variance could be decomposed into non-shared environmental effects (e(2) = 0.19), additive genetic effects (h(2) = 0.42), and the effect of the Met11Thr variations (q(2) = 0.39).
- Published
- 2006
- Full Text
- View/download PDF
23. Cycloxygenase-2 is expressed in vasculature of normal and ischemic adult human kidney and is colocalized with vascular prostaglandin E2 EP4 receptors.
- Author
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Therland KL, Stubbe J, Thiesson HC, Ottosen PD, Walter S, Sørensen GL, Skøtt O, and Jensen BL
- Subjects
- Adult, Angiotensin II antagonists & inhibitors, Cells, Cultured, Cyclooxygenase 2, Endothelium, Vascular cytology, Endothelium, Vascular embryology, Enzyme Inhibitors pharmacology, Fetus, Gene Expression Regulation, Developmental drug effects, Gene Expression Regulation, Developmental physiology, Humans, Immunohistochemistry, Isoenzymes antagonists & inhibitors, Isoenzymes metabolism, Kidney embryology, Membrane Proteins, Prostaglandin-Endoperoxide Synthases metabolism, RNA, Messenger analysis, Receptors, Prostaglandin E metabolism, Receptors, Prostaglandin E, EP4 Subtype, Renal Artery Obstruction metabolism, Renal Artery Obstruction physiopathology, Umbilical Arteries cytology, Umbilical Arteries embryology, Umbilical Arteries enzymology, Endothelium, Vascular enzymology, Ischemia physiopathology, Isoenzymes genetics, Kidney blood supply, Prostaglandin-Endoperoxide Synthases genetics, Receptors, Prostaglandin E genetics
- Abstract
The study was performed to elucidate the distribution and cellular localization of cyclooxygenase (COX)-2 in human kidney and to address localization of downstream targets for COX-derived prostanoids. Cortex and outer and inner medulla tissue were obtained from control kidneys (cancer specimens), kidneys with arterial stenosis, and kidneys of patients who received angiotensin II inhibition or acetylsalicylic acid. Ribonuclease protection assay and Western blot test revealed that COX-1 and -2 mRNA and protein were expressed in all regions of human kidney (mRNA ratio, cortex:outer medulla:inner medulla COX-1 1:3:20 and COX-2 1:1:3). In adult kidney, immunohistochemical labeling for COX-2 was associated with smooth muscle cells in pre- and postglomerular vessels and with endothelium, particularly in vasa recta and medullary capillaries. Western blot test confirmed COX-2 expression in renal artery. COX-2 had a similar localization in fetal kidney and was additionally observed in Henle's loop and macula densa. Human tissue arrays displayed COX-2 labeling of vascular smooth muscle in multiple extrarenal tissues. Vascular COX-2 expression was significantly increased in kidneys with arterial stenosis. COX-1 was colocalized with microsomal prostaglandin E(2) synthase (PGES) in collecting ducts, and PGES was also detected in macula densa cells. Vascular COX-2 was colocalized with prostaglandin E(2) EP4 receptors but not with EP2 receptors. Thus, renovascular COX-2 expression was a constitutive feature encountered in human kidneys at all ages, whereas COX-2 was seen in macula densa only in fetal kidney. Vascular COX-2 activity in human kidney and extrarenal tissues may support blood flow and affect vascular wall-blood interaction.
- Published
- 2004
- Full Text
- View/download PDF
24. Phospho-proteomics: evaluation of the use of enzymatic de-phosphorylation and differential mass spectrometric peptide mass mapping for site specific phosphorylation assignment in proteins separated by gel electrophoresis.
- Author
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Larsen MR, Sørensen GL, Fey SJ, Larsen PM, and Roepstorff P
- Subjects
- Alkaline Phosphatase, Animals, Binding Sites, Caseins chemistry, Electrophoresis, Gel, Two-Dimensional, Humans, Keratins chemistry, Mice, Ovalbumin chemistry, Peptide Elongation Factor 1 chemistry, Peptide Fragments chemistry, Peptide Fragments isolation & purification, Phosphorylation, Spectrometry, Mass, Electrospray Ionization, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Trypsin, Mass Spectrometry methods, Peptide Mapping methods, Phosphoproteins chemistry, Proteome chemistry
- Abstract
Detection of phosphorylated proteins as well as assignment of the phosphorylated sites in such proteins is a major challenge in proteomics. In the present study we evaluate the use of enzymatic de-phosphorylation in combination with differential peptide mass mapping for identification of phosphorylated peptides in peptide mixtures derived from in-gel digested phospho-proteins. Phospho-peptides could be identified provided that improved sample preparation methods prior to mass spectrometric analysis were used. An attempt to identify the proteins visualized by [32P] autoradiography in a proteomics study and their phosphorylation sites, demonstrated that protein identification was possible whereas reliable identification of the phospho-peptides requires more protein than normally available in our proteomics studies.
- Published
- 2001
- Full Text
- View/download PDF
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