121. Modifizierte Technik der „Ersatzklappen”-Operation an der V. poplitea bei postthrombotischem Syndrom

Zusammenfassung Die Technik der Ersatzklappen-Operation an der V. poplitea bei postthrombotischem Syndrom wurde vom Initiator durch die Verwendung einer 24cm langen Silicone-Sehne modifiziert. Die Silicone-Sehne wird zwischen A. und V. poplitea durchgezogen, ihr mediales Ende an die Gracilissehne und ihr laterales Ende um die Bicepssehne vernäht. Bei 31 durchgeführten Operationen konnte klinisch und phlebographisch bei allen eine regelrechte Ersatzklappen-Funktion und eine Besserung der venösen Hämodynamik des Beines festgestellt werden.     

Complex role of tumor cell transforming growth factor (TGF)-βs on breast carcinoma progression

Growth inhibition by the TGF-s has been extensively studied in both normal and transformed mammary epithelial cells. It has been proposed that loss of autocrine TGF- mediated growth regulation is a critical event in breast tumorigenesis and several lines ofin vitro andin vivo data support this hypothesis. However, a positive association between the expression of TGF-s by tumor cells and the progression or maintenance of breast cancinoma cells has been observed in many studies inin vivo tumor models. Possible mechanisms for these growth enhancing effects of TGF- include immunosuppression mediated by tumor TGF-s, enhanced angiogenesis, increased peritumoral stroma formation, and cell adhesion. The net effect of tumor cell TGF- on the biology of breast carcinogenesis would depend on the balance between autocrine growth inhibition of mammary epithelial cells and these growth enhancing effects.     

Some remarks on breast reduction by the “B” technique

The main disadvantage of the popular techniques for breast reduction are the scars left around the breasts. We present our experience with the B technique for breast reduction, which creates a much smaller size scar that is well hidden under the brassiere. Our conclusion is that the B technique is the method of choice for most breast reductions.     

Cranioplasty of an extremely large cranial defect caused by transitional meningioma with a knitted polypropylen-polyester prothesis “Codubix”

Summary The authors report a case of transitional cell meningioma of the convexity which destroyed a large portion of the calvarium and invaded subcutaneous tissue. The tumour was totally removed and a large cranial defect/430 cm² in size/ was filled with a polypropyleno-polyester knitted prothesis Codubix with an excellent result.The problems of chronioplastic closure of such an unusually large skull defect and the advantages of the use of the material Codubix are discussed.     

Demonstration of TGF-β1 mRNA by in situ hybridization in normal human fracture healing

Summary The role of transforming growth factor (TGF-) in fracture healing has previously been investigated in a rodent model, but not in human material. We investigated TGF-1 gene expression in specimens of callus from normally healing human fractures, using in situ hybridization to a cDNA TGF-1 probe and an autoradiographic disclosure system. TGF-1 mRNA was present in areas of proliferation of mesenchymal tissue, bone, and cartilage. Levels of expression were lower in cells in the fracture hematoma and in differentiated (hypertrophic) chondrocytes. These results are compatible with those found in various animal models using immunohistochemistry and support the view that locally produced TGF-1 is a regulator of fracture repair in humans from the early (mesenchymal proliferation) stage to the stage of remodeling of woven bone. They also indicate that, for TGF-1, animal models accurately reflect human bone repair.     

Regulated Expression of G Protein-Coupled Receptor Kinases (GRK’s) and β-Arrestins in Osteoblasts

Desensitization of G-protein coupled receptors (GPCRs) is largely mediated by a family of enzymes and protein co-factors termed GRKs and arrestins, respectively. In the present studies, we investigated expression of GRKs and arrestins in osteoblastic cell lines concentrating on the enzymes (GRK2 and GRK3) and protein co-factors (-arrestint 1 and -arrestin 2) that play dominant roles in regulating GPCR responsiveness in most tissues and cell types. We found that osteoblastic cells express similar amounts of GRK2 with either undetectable or lesser amounts of GRK3. In contrast, expression of -arrestin 1 and -arrestin 2 by osteoblastic cells varied between cell lines. To determine if GRK2 or -arrestin expression is modulated during osteoblast development, we assessed expression of GRK2 and -arrestin proteins during differentiation of the mouse osteoblastic cell line MC3T3-E1 cells over a 21-day period. We found that expression of GRK2 and -arrestin 2 increased to maximal levels by day 7 and then decreased 4-fold by day 21. In contrast, expression of -arrestin 1 increased to maximal levels by day 14 and then decreased 2-fold by day 21. Over this same time period (days 7–21), PTH/PTHrP receptor number decreased to a greater extent than the decrease in PTH(l-34)-induced cAMP generation, suggesting that responsiveness of individual PTH/PTHrP receptors was enhanced in differentiated cells. We conclude that (l) osteoblastic cell lines differentially express the enzymes and protein co-factors that modulate GPCR responsiveness and (2) expression of both GRK2 and -arrestins is temporally regulated during osteoblast development. These data are consistent with the notion that GPCR responsiveness may be differentially regulated in osteoblastic cell lines and during osteoblast development.     

„Fast-track“-Chirurgie

Zusammenfassung Die fast-track-Chirurgie ist ein multimodales Behandlungskonzept zur Beeinflussung pathophysiologischer funktioneller Veränderungen nach elektiven Eingriffen mit dem Resultat der verminderten Morbidität und beschleunigten Rekonvaleszenz. Erreicht wird dies durch eine optimierte interdisziplinäre (Chirurg, Anästhesist, Pflegepersonal, Physiotherapeut) und perioperative Fürsorge, welche zu einer verminderten operativen Stressreaktion des Patienten führt. Hierdurch konnten z. B. nach elektiven Kolonresektionen die Rate allgemeiner postoperativer Komplikationen und die Krankenhausliegezeiten deutlich gesenkt werden. Voraussetzung bei der Einführung der fast-track-Chirurgie ist der Wille der verantwortlichen Chirurgen zur Veränderung konventioneller Konzepte. Das Grundprinzip des fast-track-Managements wird zunehmend mit Erfolg auch auf andere abdominalchirurgische Operationen und andere operative Fächer wie z. B. die Urologie ausgeweitet.     

Photodynamic therapy and γ-irradiation of tumours: Effect of tumour-cell reoxygenation

The presence of adequate oxygen appears to be essential for photodynamic therapy (PDT) of tumours (1, 2). We used the mouse sarcoma 180 tumour model to investigate how the reoxygenation of the tumour cell population after a single exposure to -irradiation influenced the effect of photodynamic therapy. The combination of -irradiation with PDT leads to a significant enhancement of the therapeutic effect. The best effect is observed when the -irradiation precedes the PDT by 24 h, at which time reoxygenation of the tumour is greatest. Also, there is some enhancement of the effect when PDT is given before -irradiation, although the mechanism of this is not yet clear.