Search PubMed⌕ Search

Biomedical subjects

W Mutschler

Publications and source records attributed to W Mutschler.

157 records · Page 9Linked to original sources
PubMed1980

[Experimental and clinical experiences with the synthetic skin cover of polyvinylalcohol-formaldehyde foam (PVA)].

Animal experimental research and clinical experience in polyvinylalcohol formaldehyde foam (PVA) as a temporary skin cover: The usefulness of PVA as a temporary skin cover of burns and infected wounds was studied in animals. On the back of 20 pigs full thickness burns were produced and wounds were infected, then examined macroscopically, histologically and bacteriologically over a period of 18 days. PVA showed a better wound cleansing, a significantly reduced bacterial flora and a more rapid growth of the epithelium in comparison with three other materials. The clinical use of PVA in the treatment of compound fractures with a severe damage of soft tissue, of infected wounds and of burns also demonstrated a quick cleansing of the wound and an induction of a dense and vascularised granulation tissue. Thus considerable infections could be avoided and early grafting was possible.

Adult↗
PubMed1980

[Biomechanical and histologic evaluation of refixation of ruptured collateral ligaments (author's transl)].

This paper describes the use of a new one-hole plate for the refixation of ligaments. The anchorage of ligaments was of sufficient strength as judged by biomechanical experiments on medial collateral ligaments of sheep in vivo and knees of human cadavers. Microangiographic and histologic investigations showed good vascularization and normal structure of the ligament under the one-hole plate.

Animals↗
PubMed1979

[The appearances of chondropathia patellae on plain films (author's transl)].

The ability to diagnose chondropathia patellae on plain radiographs was studied in 64 patients in whom the disease had been confirmed either by operation or arthroscopy. All cases of stage III chondropathia were diagnosable by radiological examination; in stage I, 67%, and in stage II, 73% could be diagnosed. The diagnosis depends on the co-existence of marginal irregularities, irregularities of the subchondral bone lamellae, spotty diffuse demineralisation, marginal osteophytes, irregularities at the insertion of the quadriceps tendon and soft tissue changes such as joint effusions. These changes are best identified on the so-called "defilée" view. Disalignment of the axis of the patella and post-traumatic defects are of particular importance for the development of chondropathia, but in the present clinical material, the existence of dysplasia of the patella or of the femoral condyle was not associated with a demonstrable increase of chondromalacia.

Cartilage Diseases↗
PubMed1979

[Experimental studies on the biomechanics of the lateral ligaments of the knee joint].

Measurements of absolute strain and stress on collateral ligaments of human knees were made with two new measuring cells. The medial collateral ligament was found to have three functional different parts, the most important of which was the ventral. During motion of the knee, tensile forces amounted to about 20 N when the lateral ligament was in extension and the medial ligament in full flexion. Moments of abduction and adduction increased strain and stress manyfold.

Biomechanical Phenomena↗
PubMed1978

[Biomechanical efficiency and biocompatibility of lubricating sprays PTFE or graphite (author's transl)].

The screws and plates used in operative treatment of fractures cause moments of friction between the bone screw head and the bone plate hole during the tightening of the screws. This results in hidden damage to the grinding metal surfaces, with the danger of erosion corrosion and in a reduction in the screw force. By covering the screw heads with the lubricating sprays PTFE or graphite friction was significantly reduced, the screw force increased by 40% and extensive damage to the surfaces avoided. Lubricating sprays or their extracts, in fetal calf serum or in dimethylsulfoxide, were added to fibroblast cultures. Toxicity was manifest as changes in the synthesis of DNA, as measured by autoradiography. Sprays or spray extracts in fetal calf serum did not inhibit cell proliferation. In vivo experiments in rats reflected the in vitro results, there being no evidence that toxic substances were released from the sprays by physiological solvents: There was a lack of histopathological changes in the inner organs and a local encapsulation of implants which was essentially like that in a teflon control group.

Aerosols↗
PubMedDate not supplied

Centrosome multiplication accompanies a transient clustering of polyploid cells during tissue repair.

Cells from different human wounds were analyzed concerning their degree of ploidy. The experiments showed an increased tetraploidization rate in well-healing wounds especially during inflammation and proliferation. Recent data described a polyploidization in different tissues, which is accompanied and maybe caused by the multiplication of the centrosome. We show here for the first time that cells from nonmalignant tissue, namely human wound cells, are characterized by an extensive centrosome multiplication. In an effort to identify a certain mechanism, by which the centrosome may act as a modulator of the cells' ploidy, we focused our interest on p53, whose interaction with the centrosome was recently described. Applying a wound model onto p53-wildtype (wt) and p53-knockout (ko) mice, we could show that polyploidization was not reversible in p53-ko mice during wound healing. The lack of p53, the centrosome multiplication, and the polyploidization therefore may contribute to the physiological process of tissue repair in physiologically "normal" tissue.

Animals↗
PubMedDate not supplied

[3D-Culturing of human osteoblastic cells with vessel like nutrient supply].

AIM: The treatment of large, critical-size bone defects is a major therapeutic problem in orthopaedic and reconstructive surgery. The engineering of bone tissue could be used to replace lost bone mass. However, scaffolds seeded with vital cells and cultured in vitro suffer from poor oxygen and nutrient supply centrally, when the constructs exceed a critical volume. Therefore, we have established an osteoblastic cell culture in a new 3D-culture chamber with an artificial, vessel-like central membrane, allowing continuous nutrient supply. METHOD: Human osteoblasts were cultured in a 3D-like manner using a perfusion chamber for one week. In this system, the nutrient supply is guaranteed by a vessel-like, semipermeable polysulfone membrane with a continuous flow of medium. After fixation and cryosectioning, histological and immunohistological staining and scanning electron microscopy was carried out. RESULTS: Examinations reveal 3D cell growth around the central vessel. Formation of an extracellular matrix, rich in collagen type I and fibronectin, was detected immunohistochemically. Furthermore, we demonstrated cell adherence to the membrane and examined the surface morphology by scanning electron microscopy. CONCLUSION: The innovative approach for 3D-culturing of human osteoblasts in a system with a central nutrient supply opens up new possibilities for the in vitro cultivation for tissue engineering.

Cell Culture Techniques↗
PubMedDate not supplied

Tibial shaft fractures: assessment of fracture healing with computed tomography.

OBJECTIVE: To assess the capability of CT in assessing stability of tibial shaft fractures with planimetry. MATERIALS AND METHODS: Eighteen patients with fracture of the tibial shaft were treated by external fixator. All patients underwent CT 1, 6, 12, and 18 weeks postoperatively to assess the fracture healing. The callus formation and compacta were determined with planimetry. Fractometry, a noninvasive method to measure stability, was used as the gold standard to determine the stability of the fracture. RESULTS: The patients were divided into three groups according to different periods of time for removal of external fixation. Twelve patients with stable fractures showed a steady increase of callus, which was 50% higher after 12 weeks. Three patients with delayed fracture healing demonstrated an increase of callus of > 50% after 18 weeks. Three patients with unstable fractures obtained only callus formation of < 20% after 15-18 weeks. The external fixator was removed and endomedullary nails were used for stabilization. CONCLUSION: The CT data allow quantification of callus and compacta formation and are able to determine the stability of tibial shaft fractures.

Adolescent↗