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- Hellman, Urban, 1966-, et al.
(författare)
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Presence of hyaluronan in lung alveoli in severe Covid-19 : an opening for new treatment options?
- 2020
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Ingår i: Journal of Biological Chemistry. - : American Society for Biochemistry and Molecular Biology. - 0021-9258 .- 1083-351X. ; 295:45, s. 15418-15422
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Tidskriftsartikel (refereegranskat)abstract
- Severe corona virus disease 2019 (Covid-19) is characterized by inflammation of the lungs with increasing respiratory impairment. In fatal Covid-19, lungs at autopsy have been filled with a clear liquid jelly. However, the nature of this finding has not yet been determined.The aim of the study was to demonstrate if the lungs of fatal Covid-19 contain hyaluronan as it is associated with inflammation and acute respiratory distress syndrome (ARDS) and may have the appearance of liquid jelly.Lung tissue obtained at autopsy from three deceased Covid-19 patients was processed for hyaluronan histochemistry using a direct staining method and compared with staining in normal lung tissue.Stainings confirmed that hyaluronan is obstructing alveoli with presence in exudate and plugs, as well as in thickened perialveolar interstitium. In contrast, normal lungs only showed hyaluronan in intact alveolar walls and perivascular tissue. This is the first study to confirm prominent hyaluronan exudates in the alveolar spaces of Covid-19 lungs, supporting the notion that the macromolecule is involved in ARDS caused by SARS-CoV-2. The present finding may open up for new treatment options in severe Covid-19, aiming at reducing the presence and production of hyaluronan in the lungs.
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| 2. |
- Hellman, Urban, 1966-, et al.
(författare)
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Hyaluronan concentration and molecular mass in psoriatic arthritis : biomarkers of disease severity, resistance to treatment, and outcome
- 2019
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Ingår i: Scandinavian Journal of Rheumatology. - : Taylor & Francis Group. - 0300-9742 .- 1502-7732. ; 48:4, s. 284-293
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Low molecular mass hyaluronan causes inflammatory processes and can act as a pro-inflammatory cytokine in skin and other sites of activity in psoriatic arthritis (PsA). This study investigated whether the molecular mass distribution of hyaluronan (HA) in skin and the quantity of circulating HA are related to the clinical inflammatory picture in PsA with active disease and to the effect of treatment with anti-tumour necrosis factor-α (anti-TNF-α) adalimumab.Methods: Twenty patients with TNF-α-naïve active polyarticular PsA were included in this prospective clinical trial of treatment with 40 mg s.c. adalimumab according to standard procedure. Clinical activity, patients’ assessments, and skin biopsies were captured at inclusion and at the 12 week follow-up. Ten healthy individuals were recruited for comparison of HA analyses. Histochemistry of skin inflammation, serum HA, and molecular mass of HA were determined.Results: Overall improvements in clinical parameters were observed. Eight of 18 patients reached minimum disease activity after 12 weeks and disease activity was significantly reduced (p < 0.0001). Patients with elevated serum HA values were significantly older, had later onset of arthritis and more deformed joints, still had swollen joints after treatment, and had more circulating inflammatory biomarkers. More severe disease pathology showed a wide spectrum of high-molecular-mass HA accompanied by low mass HA. The treatment appears partly to normalize the HA mass distribution.Conclusion: HA concentration and mass seem to be two possible factors in the inflammatory pathology of PsA acting as biomarkers for disease severity, resistance to treatment, and worse outcome.
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| 3. |
- Kerje, Susanne, et al.
(författare)
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Is low molecular hyaluronan an early indicator of disease in avian systemic sclerosis?
- 2016
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Ingår i: Connective Tissue Research. - : Taylor & Francis. - 0300-8207 .- 1607-8438. ; 57:5, s. 337-346
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Tidskriftsartikel (refereegranskat)abstract
- AIM OF THE STUDY: To further elucidate the pathogenesis of systemic sclerosis (SSc) an experimental avian model was used. University of California at Davies line 200-chicken (UCD-200) spontaneously develops a SSc like disease that has most features of human SSc with vascular effects, inflammation, autoimmunity and fibrosis. The first signs of disease in UCD-200 are swelling and ischemic lesions of the comb, a tissue containing high amounts of the glycosaminoglycan hyaluronan. The aim was to evaluate inflammatory and fibrotic processes of the disease with regard to the molecular weight of hyaluronan.MATERIAL AND METHODS: Comb biopsies from UCD-200 and healthy White Leghorn (WL) chickens as controls at different ages were studied with histochemical localization of hyaluronan, hyaluronidase 1, CD3, IgY and collagen I and III. Hyaluronan molecular weight distribution was estimated with gas phase electrophoretic analysis.RESULTS: At 2 days of age hyaluronan was visualized in UCD-200 at the dermal part of the comb with no simultaneous staining of Hyal-1. In adult UCD-200 the comb skin was almost totally devoid of hyaluronan compared to WL of the same age. An increase of low molecular weight (LMW) hyaluronan was detected in comb tissue from UCD-200 at 1 day, 1, 2, 4 weeks in contrast to adult animals.CONCLUSIONS: An early inflammatory process involving LMW hyaluronan was confirmed as a possible profibrotic process. This indicates that hyaluronan might be an important participant in early inflammatory events of SSc in UCD-200 chicken and that disappearance of hyaluronan in skin predisposes to fibrosis.
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| 4. |
- Opheim, Leif Runar, et al.
(författare)
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Hyaluronan in Human Vocal Folds in Smokers and Nonsmokers : A Histochemical Study
- 2016
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Ingår i: Journal of Voice. - : Elsevier BV. - 0892-1997 .- 1873-4588. ; 30:3, s. 255-262
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES/HYPOTHESIS: To study the hyaluronan occurrence in human vocal folds, with special regards to gender and smoking and to discuss the implications of findings.STUDY DESIGN: This is a descriptive/morphologic study.METHODS: Sixteen cadaveric vocal folds from eight individuals between 58 and 90 years old (six women and two men) were removed and studied morphologically. Three of the individuals had been cigarette smokers. A direct method for hyaluronan histochemistry using a hyaluronan-binding protein probe (HABP) was used to visualize the polysaccharide. Five examiners performed an analysis of the intensities of hyaluronan staining, independently.RESULTS: We observed intense hyaluronan staining of the vocal folds of which those from women stained considerably stronger than those from men. Stratified squamous epithelium stained for hyaluronan in all sections, whereas respiratory epithelium only stained weakly or not at all. The highest accumulation of hyaluronan occurred subepithelially in the lamina propria, corresponding to Reinke's space. It was observed that vocal folds from smokers were more intensively stained than those from nonsmokers.CONCLUSIONS: Hyaluronan is found in all layers of the human vocal fold. Contradictory to earlier studies, hyaluronan was visualized in squamous epithelium, where it may function as an impact protector. The occurrence of hyaluronan in smokers may have implications in the development of vocal fold inflammation and tumor initiation as hyaluronan is an important molecule in these processes.
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| 5. |
- Do, Lan, et al.
(författare)
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High Sensitivity Method to Estimate Distribution of Hyaluronan Molecular Sizes in Small Biological Samples Using Gas-Phase Electrophoretic Mobility Molecular Analysis.
- 2015
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Ingår i: International Journal of Cell Biology. - : Hindawi Limited. - 1687-8876 .- 1687-8884.
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Tidskriftsartikel (refereegranskat)abstract
- Hyaluronan is a negatively charged polydisperse polysaccharide where both its size and tissue concentration play an important role in many physiological and pathological processes. The various functions of hyaluronan depend on its molecular size. Up to now, it has been difficult to study the role of hyaluronan in diseases with pathological changes in the extracellular matrix where availability is low or tissue samples are small. Difficulty to obtain large enough biopsies from human diseased tissue or tissue from animal models has also restricted the study of hyaluronan. In this paper, we demonstrate that gas-phase electrophoretic molecular mobility analyzer (GEMMA) can be used to estimate the distribution of hyaluronan molecular sizes in biological samples with a limited amount of hyaluronan. The low detection level of the GEMMA method allows for estimation of hyaluronan molecular sizes from different parts of small organs. Hence, the GEMMA method opens opportunity to attain a profile over the distribution of hyaluronan molecular sizes and estimate changes caused by disease or experimental conditions that has not been possible to obtain before.
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| 8. |
- Hellström, Martin, et al.
(författare)
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The structure of the basement membrane zone differs between keloids, hypertrophic scars and normal skin : A possible background to an impaired function
- 2014
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Ingår i: Journal of Plastic, Reconstructive & Aesthetic Surgery. - : Elsevier BV. - 1748-6815 .- 1878-0539. ; 67:11, s. 1564-1572
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Tidskriftsartikel (refereegranskat)abstract
- Scar tissues were collected from patients with keloids, hypertrophic scars and mature scars. Normal skin was obtained from healthy individuals. Clinical attributes were used to select which tissue to obtain but the distribution of the specific hyaluronan (HA) staining was then used for the definite classification of the various scar types. Light microscopic and ultrastructural analyses were performed with an HA-binding probe, antibodies for collagen I and III and staining for mast cells. Ultrastructural studies of keloids revealed an altered collagen structure in the dermal layers, with an abundance of collagen fibres of similar diameter in both the reticular dermis (RD) and the papillary dermis (PD) compared to normal skin. Furthermore, the keloids displayed epidermal changes, which involved the basement membrane (BM), with fewer hemidesmosomes and an altered shape of desmosomes in the entire enlarged spinous layer. The frequency of mast cells found in keloids was lower than in other scar tissues and normal skin. These alterations in epidermis could influence the hydrodynamic and cell regulatory properties of the wounded skin with impaired function and insufficient regulative capacity to hinder the ever-growing collagen tissue that is characteristic for keloids. (C) 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
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