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| 2. |
- Chambers, R C, et al.
(författare)
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Cadmium inhibits proteoglycan and procollagen production by cultured human lung fibroblasts
- 1998
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Ingår i: American Journal of Respiratory Cell and Molecular Biology. - : American Thoracic Society. - 1044-1549 .- 1535-4989. ; 19:3, s. 498-506
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Tidskriftsartikel (refereegranskat)abstract
- Chronic inhalation of cadmium at the workplace or in cigarette smoke is associated with emphysema, a disease characterized by extensive disruption of lung connective tissue. We have previously shown that cadmium, at noncytotoxic doses, inhibits fibroblast procollagen production in vitro, with maximal inhibitory effects of 69 +/- 6% (P < 0.01) at 30 µM cadmium chloride (CdCl2). In this paper we show that at similar doses, cadmium also inhibits proteoglycan synthesis, with values reduced by between 36 +/- 4% (P < 0.01) and 42 +/- 6% (P < 0.01) for proteoglycans secreted into the culture media and associated with the cell layer, respectively. The greatest inhibition was obtained for the major matrix-associated proteoglycans, versican, decorin, and the large heparan sulfate proteoglycans, with synthesis values reduced by between 60 and 70%. Biglycan and other heparan sulfate proteoglycans were also affected, with synthesis values reduced by between 25 and 45%. In contrast, total protein synthesis was unaffected. Furthermore, effects of cadmium at the protein level were mirrored by reduction in messenger RNA levels for alpha1(I) procollagen, versican, and decorin. These data support the hypothesis that cadmium may play an important role in the pathogenesis of emphysema associated with chronic inhalation of cadmium fumes by inhibiting the production of connective tissue proteins.
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| 3. |
- Falconer, C, et al.
(författare)
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Changes in paraurethral connective tissue at menopause are counteracted by estrogen
- 1996
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Ingår i: Maturitas. - 0378-5122. ; 24:3, s. 197-204
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study whether the transition to menopause is accompanied by changes in the paraurethral connective tissue and if these changes are modified by estrogen replacement therapy.STUDY DESIGN: Biopsies were obtained from the paraurethral tissue from 34 women; 12 menstruating, 14 postmenopausal without estrogen treatment, and 8 with estrogen treatment. Collagen concentration and collagen extractability by pepsin digestion were measured. Proteoglycan composition and concentration were analysed using Alcian blue. The mRNA levels for collagen I and III, the small proteoglycans (PGS) decorin and biglycan, and the large proteoglycan versican, were estimated.RESULTS: The paraurethral biopsies consisted of fibrous connective tissue, with collagen fibers as dominating structure. Several proteoglycans were identified; versican, heparansulphate proteoglycans, biglycan and decorin. The small proteoglycan decorin represented 85% of all proteoglycans. The collagen concentration was almost doubled in postmenopausal biopsies compared to premenopausal. The collagen fibril organization was also changed with higher cross-linking after menopause whereas the amount and the composition of the proteoglycans were unchanged. The proteoglycan/collagen ratio was significantly decreased. Estrogen replacement therapy resulted in decreased collagen concentration, decreased cross-linking of the collagen and reversal of the PGS/collagen ratio to almost premenopausal level. The therapy resulted in increased levels of mRNA for collagen I and III which suggests that the changes are due to an increased turnover.CONCLUSION: The decrease in estrogen levels at menopause results in a connective tissue with different qualities after menopause. Estrogen replacement therapy tends to restore the metabolism of the genitourinary connective tissue to premenopausal conditions.
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| 4. |
- Falconer, C, et al.
(författare)
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Paraurethral connective tissue in stress-incontinent women after menopause
- 1998
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - 0001-6349. ; 77:1, s. 95-100
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: To study whether stress urinary incontinence after menopause is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.METHODS: Transvaginal biopsies were obtained from the paraurethral connective tissue in stress urinary incontinent women after menopause with and without estrogen replacement therapy, and from comparable controls. All the stress-incontinent women underwent urodynamic investigation. In the specimens, collagen concentration, measured as hydroxyproline, and the degree of extractability by pepsin digestion, were quantified. Proteoglycan composition and concentration were analyzed using Alcian Blue precipitation, followed by electro-phoretic separation and quantification. Using Northern blots, mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen structure was examined with transmission electron microscopy, and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).RESULTS: No significant difference in paraurethral connective tissue biochemistry or ultrastructure was registered between women with stress incontinence and controls. Estrogen replacement therapy resulted in a lower collagen concentration both between the controls (p = 0.02) and between the incontinent women (0.02). In the women with stress incontinence also the extractability by pepsin digestion was higher in the group with estrogen treatment (p = 0.004), indicating a decrease in cross-linking. The proteoglycan/collagen ratio was higher in the control group with estrogen treatment compared to untreated (p = 0.02), but no difference was found between estrogen treated and untreated incontinent women. The median collagen fibril diameter was 15% larger in the incontinent group of women without estrogen therapy compared to the control group and 5% larger when comparing the incontinent group on estrogen replacement therapy to the corresponding control group.CONCLUSION: The extracellular matrix of paraurethral connective tissue in stress urinary incontinent women after menopause reacted differently to estrogen replacement therapy compared to continent controls. In contrast to incontinent women of fertile age no major changes in collagen metabolism were found in stress urinary incontinent women after menopause.
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| 5. |
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| 6. |
- Juhasz, P., et al.
(författare)
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ESI and MALDI LC/MS-MS approaches for large scale protein, identification and quantification : Are they equivalent?
- 2002
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Ingår i: ; , s. 55-56
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Konferensbidrag (refereegranskat)abstract
- An approach for large scale protein identification and quantification was described. The peptide mixtures from the strong cation exchange (SCX) fractionated protein digests were separated and analyzed by HPLC MS/MS. The human fibrobalst nuclei were purified from stimulated and non-stimulated cells. The quantification results with MALDI and ESI LC/MS were shown to be identical within experimental error.
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| 7. |
- Westergren-Thorsson, G., et al.
(författare)
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Proteome
- 2006
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Ingår i: Encyclopedia of Respiratory Medicine : Volume 1-4 - Volume 1-4. - 9780123708793 - 9780123708793 ; 1-4, s. 527-532
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Proteomics can be defined as the studies of protein properties on a large scale to obtain a global view of biological processes at the protein level. Essentially, proteomics requires protein separation and identification, and in many cases quantification. The cornerstones in proteomics are protein/peptide separation by gel electrophoresis and/or different chromatographic techniques, and identification by mass spectrometry followed by bioinformatic and biological interpretation of data. By combining these different separation techniques and mass spectrometry it is now possible to identify low abundant proteins with 10-1000 copies per cell. Today, substantial research efforts in proteome studies of the lung are focused on obtaining new diagnostic markers, as well as fingerprinting disease mechanisms.
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| 8. |
- Andersson, C. K., et al.
(författare)
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Uncontrolled asthmatics have increased FceRI+ and TGF-β–positive MCTC mast cells and collagen VI in the alveolar parenchyma
- 2018
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894. ; 48:3, s. 266-277
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Tidskriftsartikel (refereegranskat)abstract
- Background: Asthma has been associated with increased collagen deposition in both conducting airways and alveolar parenchyma. Mast cells (MCs) are key effector cells in asthma and have the ability to affect collagen synthesis. However, the link between clinical control and changes in bronchial and alveolar MC phenotypes and specific collagens in controlled and uncontrolled asthma remains unknown. Objective: To investigate MC phenotypes in correlation with deposition of specific collagen subtypes in patients with controlled and uncontrolled asthma as well as to healthy controls. Methods: The tissue expression of IgE+, FcεRI+ and TGF-β+ MCs, as well as immunoreactivity of collagen I, III and VI, was assessed using immunohistochemistry on bronchial and transbronchial biopsies from controlled asthmatics (n = 9), uncontrolled asthmatics (n = 16) and healthy controls (n = 8). Results: In the alveolar parenchyma, the total number of MCs, as well as the number of FcεRI+ MCs and pro-fibrotic TGF-β+ MCTC, was significantly increased in uncontrolled asthma compared to both controlled asthma and healthy controls. The proportion of TGF-β+ MCTC correlated positively to an increased immunoreactivity of alveolar collagen VI but not collagen I and III. Collagen VI was increased in the alveolar parenchyma of uncontrolled asthmatics compared to controlled asthmatics. Controlled asthmatics had an increased deposition of alveolar collagen I. In bronchi, the immunoreactivity of collagen I was increased in both controlled and uncontrolled asthmatics while collagen III was increased only in controlled asthmatics. Conclusions: Patients with uncontrolled atopic asthma have an altered pro-fibrotic MCTC phenotype in the alveolar parenchyma that is associated with alveolar collagen VI. The present data thus support distal lung mast cell and matrix changes as histopathological features of asthma that may be of particular clinical relevance in patients who have remaining symptoms despite conventional inhaler therapy.
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| 9. |
- Arroyo-Yanguas, Yolanda, et al.
(författare)
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Binding, internalization, and degradation of antiproliferative heparan sulfate by human embryonic lung fibroblasts
- 1997
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Ingår i: Journal of Cellular Biochemistry. - 0730-2312. ; 64:4, s. 595-604
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Tidskriftsartikel (refereegranskat)abstract
- Binding, internalization, and degradation of 125I-labeled, antiproliferative, or nonantiproliferative heparan sulfate by human embryonic lung fibroblasts was investigated. Both L-iduronate-rich, antiproliferative heparan sulfate species as well as L-iduronate-poor, inactive ones were bound to trypsin-releasable, cell-surface sites. Both heparan sulfate types were bound with approximately the same affinity to one high-affinity site (Kd approximately 10(-8) M) and to one low-affinity site (Kd approximately 10(-6) M), respectively. Results of Hill-plot analysis suggested that the two sites are independent. Competition experiments with unlabeled glycosaminoglycans indicated that the binding sites had a selective specificity for sulfated, L-iduronate-rich heparan sulfate. Dermatan sulfate, which is also antiproliferative, was weakly bound to the cells. The antiproliferative effects of heparan and dermatan sulfate appeared to be additive. Hence, the two glycosaminoglycans probably exert their effect through different mechanisms. At concentrations above 5 micrograms/ml (approximately 10(-7) M), heparan sulfate was taken up by human embryonic lung fibroblasts, suggesting that the low-affinity site represents an endocytosis receptor. The antiproliferative effect of L-iduronate-rich heparan sulfate species was also exerted at the same concentrations. The antiproliferative species was taken up to a greater degree than the inactive one, suggesting a requirement for internalization. However, competition experiments with dextran sulfate suggested that both the high-affinity and the low-affinity sites are involved in mediating the antiproliferative effect. Structural analysis of the inactive and active heparan sulphate preparations indicated that although sulphated L-iduronate appears essential for antiproliferative activity, it is not absolutely required for binding to the cells. Degradation of internalized heparan sulfate was analyzed by polyacrylamide gel electrophoresis using a sensitive detection technique. The inactive species was partially degraded, whereas the antiproliferative one was only marginally affected.
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| 10. |
- Falconer, C, et al.
(författare)
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Different organization of collagen fibrils in stress-incontinent women of fertile age
- 1998
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Ingår i: Acta Obstetricia et Gynecologica Scandinavica. - : Wiley. - 0001-6349 .- 1600-0412. ; 77, s. 87-
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The objective was to test the hypothesis that stress urinary incontinence in women is correlated to changes in the paraurethral connective tissue ultrastructure and metabolism.METHODS: Transvaginal biopsies were obtained from the paraurethral connective tissue in women of fertile age with stress urinary incontinence and in matched continent controls. All the stress-incontinent women were characterized with urodynamic investigation. In the biopsies, collagen concentration, measured as hydroxyproline, and the degree of extraction by pepsin digestion were quantified. Proteoglycan composition and concentration were analyzed using Alcian blue precipitation, followed by electrophoretic separation and quantification. Using Northern blots mRNA levels for the collagens I and III, the small proteoglycans decorin and biglycan, and the large proteoglycan versican, were quantified. Collagen organization was examined with transmission electron microscopy and the diameters of collagen fibrils were analyzed with an interactive image analysis system (IBAS, Zeiss/Kontron).RESULTS: The biochemical and morphological analyses exposed a significant difference in the paraurethral connective tissue between stress urinary incontinent women before menopause and comparable controls. The collagen concentration was almost 30% higher and the diameters of the collagen fibrils were 30% larger in the incontinent group of women. Also the organization of the collagen fibrils differed, with considerably higher cross-linking. A higher level of mRNA for collagen I and III in the incontinent group indicates that the differences can be related to an altered collagen metabolism. No change of proteoglycan amount or composition was observed, resulting in a significantly lower proteoglycan/collagen ratio in the incontinent group of women.CONCLUSION: Stress urinary incontinence in fertile women is associated with a change in collagen metabolism resulting in an increased concentration of collagen and larger collagen fibrils. These alterations should result in a more rigid form of extracellular matrix, suggesting a connective tissue with impaired mechanical function.
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