| 1. |
- Gannedahl, G, et al.
(författare)
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Role of antibody synthesis and complement activation in concordant xenograft retransplantation.
- 1994
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Ingår i: Transplantation. - 0041-1337 .- 1534-6080. ; 58:3, s. 337-344
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Tidskriftsartikel (refereegranskat)abstract
- A mouse-to-rat heart retransplantation model was used to study the effects of complement depletion and antibody production with regard to graft survival and anti-donor antibody specificity. Retransplantation was performed 3 weeks after the first transplantation in the presence of absence of 15-deoxyspergualin (DSG) immunosuppression. Untreated animals rejected their first graft after 3 days and retransplantation resulted in a hyperacute rejection within 2 min. A low titer of preformed anti-mouse lymphocytotoxic antibodies of the IgM subclass was found in serum collected from the unoperated rat. The rejection gave rise to a synthesis of IgG antidonor antibodies reacting with both graft endothelium and sarcolemma. Immunofluorescent staining of the rejected first heart graft showed moderate IgM and IgG antibody deposits on the graft vascular endothelium, while only IgG was found in the second graft. There was no C3 deposition found in the first mouse graft, as was the case in the second mouse graft. Anti-mouse antibodies cross-reacted with hamster antigens and a hyperacute rejection of a hamster heart graft occurred in a mouse-sensitized rat. Immunofluorescent staining revealed that the antibodies did not bind to hamster heart endothelium, as was expected, but, instead, to graft sarcolemma. DSG treatment prolonged the survival of the first graft by a median of 8 days. Continuous treatment until retransplantation resulted in a prolongation to 30 (20-127) min of the survival of the second graft and no increase in antibody titers against mouse antigens was observed. However, immunofluorescent staining revealed a weak binding of anti-mouse antibodies of the IgM subclass in the rejected mouse heart graft. Additional complement depletion with cobra venom factor in DSG-treated animals resulted in a prolongation of the median graft survival to 48 hr (6-96). No sign or minimal signs of antibody deposition were found in these grafts, but histology revealed massive mononuclear infiltration. In conclusion, xenograft transplantation in a concordant situation results in a shift of antidonor antibody Ig synthesis from IgM to IgG. If daily DSG treatment is administered from the day of transplantation, this reduces the synthesis of antidonor antibodies, and if complement is also depleted, the survival of the second graft is prolonged. The significance of the mononuclear infiltration remains to be established.
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| 2. |
- Albrektsson, Tomas, 1945, et al.
(författare)
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Histologic investigations on 33 retrieved Nobelpharma implants.
- 1993
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Ingår i: Clinical materials. - 0267-6605. ; 12:1, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- Thirty Nobelpharma implants were retrieved from 17 patients despite a remaining clinical stability, after between 1 and 16 years of clinical function. The reasons for implant removal were bone resorption in combination with soft tissue disorders, psychological causes, implant fracture and post mortem cases. When measured at the cortical passage, there was an average of 84.9% direct bone-to-implant contact and 81.8% average surface bone area in individual threads as evaluated in a computerized morphometric system at the light microscopic level.
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| 3. |
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| 4. |
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| 5. |
- Dahlberg, L., et al.
(författare)
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Cartilage metabolism in the injured and uninjured knee of the same patient
- 1994
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Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 0003-4967. ; 53:12, s. 823-827
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Tidskriftsartikel (refereegranskat)abstract
- Objective-To examine if unilateral knee injury affects the synovial fluid concentrations of aggrecan fragments, cartilage oligomeric matrix protein (COMP) fragments, stromelysin-l, and tissue inhibitor of metalloproteinases-l (TIMP-1) in the contralateral uninjured knee. Methods-Synovial fluids from the injured and uninjured knees were obtained at different times in a group of patients after unilateral knee trauma. Serum samples were obtained on the same occasion. Concentrations of aggrecan fragments were determined by precipitation with Alcian Blue; those of COMP fragments, stromelysin-l, and TIMP-1 were measured by immunoassay. Concentrations were compared with those in a reference group of 10 healthy volunteers. Results-Immediately after knee injury, concentrations of aggrecan fragments, COMP fragments, stromelysin-l and TIMP-1 were increased in the synovial fluid of the injured knee. However, concentrations of aggrecan and COMP fragments, and stromelysin-l increased also in the contralateral uninjured knee immediately after injury, but less than in the injured knee. Subsequently, the concentrations ofall markers decreased in the synovial fluid of the injured knee, but remained unchanged in the uninjured knee. The concentration of aggrecan fragments in the injured knee decreased to less than that in the uninjured knee in the chronic phase. Serum concentrations of COMP were much smaller than those in synovial fluid. Conclusions-The increased concentrations of aggrecan and COMP fragments and stromelysin-1 in the joint fluid of the contralateral, uninjured knee following unilateral knee injury, compared with concentrations in healthy reference knees, suggest changes in joint cartilage metabolism in both knees following unilateral knee injury. The mechanisms for these changes are unclear. The low serum concentration of COMP makes it less likely that there is any significant 'exchange' of molecular markers between the knees. A further consequence of these findings is that the contralateral knee cannot be recommended as the only control joint in studies of matrix metabolism in patients with unilateral knee injury.
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| 6. |
- Lohmander, L. Stefan, et al.
(författare)
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Cartilage matrix metabolism in osteoarthritis : markers in synovial fluid, serum, and urine
- 1992
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Ingår i: Clinical Biochemistry. - 0009-9120. ; 25:3, s. 167-174
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Tidskriftsartikel (refereegranskat)abstract
- Osteoarthritis is a major cause of disability and early retirement. Yet we lack the means to diagnose the disease in its early stages or to monitor the effects of treatment on the target tissue, the joint cartilage. Neither can we identify the disease mechanisms at the tissue or cell level. Current research focuses on the use of markers of cartilage matrix metabolism in body fluids as a means to diagnose and monitor osteoarthritis. Cartilage proteoglycan, collagen and glycoprotein fragments, as well as proteinases and their inhibitors, are being suggested for this purpose. Structural information on matrix molecule fragments released into body fluids may also help to identify the enzymes active in the destruction of the cartilage, a central issue in osteoarthritis.
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| 7. |
- Lohmander, L. S., et al.
(författare)
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Stromelysin, tissue inhibitor of metalloproteinases and proteoglycan fragments in human knee joint fluid after injury
- 1993
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Ingår i: Journal of Rheumatology. - 0315-162X. ; 20:8, s. 1362-1368
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Tidskriftsartikel (refereegranskat)abstract
- Objective. To determine in a cross sectional study the concentrations of stromelysin, tissue inhibitor of metalloproteinases (TIMP), and proteoglycan fragments in knee synovial fluid (SF) at different times after injury to cruciate ligament or meniscus. Methods. Joint fluid samples were obtained from patients with knee injury diagnosed by arthroscopy. Concentrations of stromelysin-1 and TIMP-1 were determined by immunoassay with monoclonal and polyclonal antibodies. Cartilage proteoglycan fragments were quantified by immunoassay with polyclonal antibodies or by dye precipitation. Results. Average concentrations of stromelysin increased 40-fold in association with injury, and after about 6 months decreased to a plateau level about 10-fold increased compared to a reference group with healthy knees. TIMP and proteoglycan levels also increased in similar temporal patterns, but less markedly. Increased average SF levels of these markers were maintained for at least 17 years after injury. SF from knees with injury contained a 1.5 to 2.5 molar excess of stromelysin over TIMP, while reference joint fluids contained a 2-fold molar excess of TIMP over stromelysin. Conclusion. The persistent changes in SF markers after joint injury may be associated with the cartilage destruction and frequent development of posttraumatic osteoarthritis in this group of patients.
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| 8. |
- Lohmander, L. S., et al.
(författare)
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Temporal patterns of stromelysin-1, tissue inhibitor, and proteoglycan fragments in human knee joint fluid after injury to the cruciate ligament or meniscus
- 1994
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Ingår i: Journal of Orthopaedic Research. - 0736-0266. ; 12:1, s. 21-28
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Tidskriftsartikel (refereegranskat)abstract
- Stromelysin-1, tissue inhibitor of metalloproteinases-1 (TIMP-1), and proteoglycan fragments were quantified in knee synovial fluid samples in a cross-sectional study of patients who had injury to the anterior cruciate ligament or the meniscus. The average concentrations of stromelysin-1 and TIMP-1 increased 25-fold and 10-fold within the first day after the trauma, respectively, and the concentration of proteoglycan fragments increased 4- fold. From approximately 1-6 months after injury, the levels of these markers were higher after injury to the cruciate ligament than after injury to the meniscus. From 6 months to 18 years after trauma, however, the levels of stromelysin-1 and TIMP-1 in patients who had an injury to the ligament were the same as the levels in patients who had a meniscal lesion, but the levels were increased compared with those for a reference group of healthy volunteers. The molar balance of stromelysin-1 to TIMP-1 in synovial fluid in both groups of injured joints changed from a balance representing an excess of free inhibitor in the normal joint to one representing an excess of free enzyme in the injured joint. The increased release of these markers to joint fluid both early and late after trauma may be caused by a change in the loading patterns in the knee with an injured ligament or meniscus or by synovitis induced by bleeding. The increased release may be associated with the frequent development of posttraumatic osteoarthritis in patients with these injuries.
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| 9. |
- Roos, A., et al.
(författare)
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Diffuse reflectance and transmittance spectra of an interference layer : 1. Model formulation and properties
- 1994
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Ingår i: Applied Optics. - 1559-128X .- 2155-3165. ; 33:34, s. 7908-7917
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Tidskriftsartikel (refereegranskat)abstract
- A model for the calculation of the diffuse reflectance and transmittance of a single interference layer with rough interfaces on a transparent substrate is presented. The model is based on electric field calculations and scalar scattering theory, and it assumes that the interfaces of the layer are totally uncorrelated. Examples are given of calculated spectra in which the parameters of the model are varied systematically to show the influence from different interface roughness and refractive index combinations as well as absorption in the film. A wavelength-dependent effective root-mean-square roughness is introduced. This depends on the nature of the roughness, and the bandwidth limits are given by the experimental conditions. Finally, total integrated scattering spectra are calculated and the importance of taking multiple reflections in the substrate into account is shown.
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| 10. |
- Rönnow, Daniel, et al.
(författare)
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Determination of interface roughness by using a spectroscopic total-integrated-scatter instrument
- 1993
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Ingår i: Applied Optics. - 1559-128X .- 2155-3165. ; 32:19, s. 3448-3451
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Tidskriftsartikel (refereegranskat)abstract
- A spectroscopic total-integrated-scatter instrument has been constructed. It uses a Coblentz sphere for the collection of the scattered light and a lamp with a monochromator as a light source. It can be used to measure diffuse reflectance as well as transmittance. The instrument has been used to measure diffuse reflectance of thermally and chemical-vapor-deposition oxidized silicon wafers. Comparisons are made with measurements by using a spectrophotometer with an integrating sphere. The data have been interpreted with a parameterized model for light scattering from a double layer, to obtain rms surface roughness values for the two interfaces of the oxide film.
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| 11. |
- Rönnow, Daniel, et al.
(författare)
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Diffuse reflectance and transmittance spectra of an interference layer. 2. Evaluation of tin oxide-coated glass
- 1994
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Ingår i: Applied Optics. - 1559-128X .- 2155-3165. ; 33:34, s. 7918-7927
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Tidskriftsartikel (refereegranskat)abstract
- A model for the calculation of diffuse reflectance and transmittance of a single interference layer on a transparent substrate is applied to pyrolytically deposited tin oxide films on glass. Total as well as diffuse reflectance and transmittance spectra were measured in an integrating sphere, and scattering levels between 0.002 and 0.1 were recorded. The optical constants and the thickness of the films were determined from the total reflectance and transmittance spectra. The wavelength-dependent effectiveroot-mean-square roughness of aluminum-coated tin oxide front surfaces was determined by the application of the scalar scattering theory. Surface roughness values between 5 and 25 nm were obtained. The obtained effective rms roughness values of the air-film interface were used together with the other film parameters to calculate the diffuse reflectance and transmittance spectra of the tinoxide-coated glass substrates. A comparison between calculated and experimental spectra showed good agreement for diffuse reflectance, diffuse transmittance, and total integrated scattering spectra.
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| 12. |
- Rönnow, Daniel, et al.
(författare)
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Stray-light corrections in integrating-sphere measurements on low-scattering samples
- 1994
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Ingår i: Applied Optics. - 1559-128X .- 2155-3165. ; 33:25, s. 6092-6097
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Tidskriftsartikel (refereegranskat)abstract
- A method for correcting integrating-sphere signals that considers differences in the angular distribution of scattered light is extended to sources of errors that are due to stray light from imperfect optical components. We show that it is possible to measure low levels of scattering, below 1%, by using a standard integrating sphere, provided that the various contributions to stray light are taken into account properly. For low-scattering samples these corrections are more important than those from the angular distribution of the scattering. A procedure for the experimental determination of stray-light components is suggested. Simple, easy to use, compact equations for the diffuse and specular reflectance and transmittance values of the sample as functions of the recorded signals are presented.
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| 13. |
- Uvebrant, Paul, 1951, et al.
(författare)
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Evaluation of cerebrospinal fluid shunt function in hydrocephalic children using 99mTc-DTPA.
- 1992
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Ingår i: Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery. - 0256-7040. ; 8:2, s. 76-80
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Tidskriftsartikel (refereegranskat)abstract
- The increasing numbers and survival of children with shunt-treated hydrocephalus make it mandatory to refine the methods for cerebrospinal fluid (CSF) shunt function evaluation. Radionuclide shuntography with 99mTc-DTPA, which has proved to be a safe and effective method, was performed in eight children with suspected CSF-shunt dysfunction. Characteristic shuntography patterns were found for proximal and distal CSF-shunt catheter obstruction as well as for overdrainage and normal CSF-shunt function. Shuntography contributed to the explanation of suspected CSF-shunt dysfunction in all children investigated.
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