Biomedical subjects

E Kahl

Publications and source records attributed to E Kahl.

10 recordsLinked to original sources

PubMed2006

Autologous chondrocyte transplantation for treating cartilage defects of the talus.

BACKGROUND: Despite its highly specialized nature, articular cartilage has a poor reparative capability. Treatment of symptomatic osteochondral defects of the talus has been especially difficult until now. METHODS: We performed autologous chondrocyte transplantation in twelve patients with a focal deep cartilage lesion of the talus. There were seven female and five male patients with a mean age of 29.7 years. The mean size of the lesion was 2.3 cm(2). All patients were studied prospectively. Evaluation was performed with use of the Hannover ankle rating score, the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score, a visual analogue scale for pain, and magnetic resonance imaging. RESULTS: All patients were available for follow-up at a mean of sixty-three months. There was a significant improvement in the Hannover score, from 40.4 points preoperatively to 85.5 points at the follow-up examination, with seven excellent results, four good results, and one satisfactory result. The AOFAS mean score was 88.4 points compared with 43.5 points preoperatively. Magnetic resonance imaging showed a nearly congruent joint surface in seven patients, discrete irregularities in four, and an incongruent surface in one. The patients who had been involved in competitive sports were able to return to their full activity level. CONCLUSIONS: The promising clinical results of this study suggest that autologous chondrocyte transplantation is an effective and safe way to treat symptomatic osteochondral defects of the talus in appropriately selected patients.

Adolescent↗

PubMed2005

Factors that influence high tibial osteotomy results in patients with medial gonarthritis: a score to predict the results.

OBJECTIVE: High tibial osteotomy (HTO) for the treatment of unicompartmental knee osteoarthritis in the presence of axial malalignment is recognized as an effective treatment for young and active patients. The aim of this study was to identify HTO prognostic factors. METHODS: A total of 94 patients who had undergone HTO with additive arthroscopy were scored using the "knee injury and osteoarthritis outcome score" (KOOS). A KOOS of less than 114 points was judged as a poor outcome. RESULTS: A total of 84 patients were available for follow-up after a time-interval of 45.9+/-7.6 (range 34-60) months. The KOOS increased from 46.1+/-11.1 to 120.3+/-40.8. The preoperative varus angle in all patients was 7.5 degrees +/-1.9 (range 5-14 degrees ). In follow-up the patients had a mean valgus angle of 3.7 degrees +/-2.5. Twenty-three patients (27.4%) had suffered a loss of correction (0.8 degrees , range 0-2 degrees ). A loss of correction correlated with a minor result in tendency. A total of 25 patients (29.8%) had a poor KOOS. Factors associated with a poor HTO outcome were a patient history of more than 24 months, a preoperative KOOS>50 points, obesity, and smoking. However, the results were also influenced by radiological findings, such as medial tibial exophyte, a medial joint space width of less than 5mm, and intraarticular damage, such as a degree IV cartilage defect of the tibia. Gender was also a minor prognostic factor. Patient's age and the event of prior surgery did not influence the outcome. CONCLUSION: This study identified relevant factors that significantly influenced HTO results. It was possible to create a "predictive score" for HTO patients. Patients with more than 4 of the poor prognostic factors should chose primary arthroplasty.

Adult↗

PubMed2005

Clinical outcome of the arthroscopic management of sports-related "anterior ankle pain": a prospective study.

Anterior impingement syndrome is a generally accepted diagnosis for a condition characterized by anterior ankle pain with limited and painful dorsiflexion. The cause can be either soft tissue or bony obstruction. We reviewed 26 (16 male and 10 female) athletes with a mean age of 27 years treated arthroscopically for symptoms due to soft-tissue (group I, n = 12) and bony obstruction (group II, n = 14). They suffered from anterior pain, reduction of dorsiflexion and recurrent swelling with severe impairment in their sports activities. There was no clinical improvement for at least 6 months despite of conservative treatment with a mean duration of symptoms about 20 months. There were no further operations. Evaluation included the Karlsson ankle rating score, the activity score of Tegner, and a visual analogue scale (VAS) reflecting patients' pain. Conventional radiographs and Magnetic resonance imaging (MRI) were done preoperatively. All patients were available for follow up after 31 months (range, 25-48 months) with a significant improvement (p < 0.05) of the Karlsson score from 66 to a mean of 92 at the follow-up examination. The mean Tegner score was eight points compared to three points preoperatively. Regarding the subjective assessment observed by the decrease of pain and the ability of the athelete to return to competition sport, there were 25 very satisfied and one unsatisfied athlete. No significant difference in the outcome of group I and II (p > 0.05) could be estimated. The results demonstrate ' excellent ' to ' good ' results for arthroscopic treatment of sports-related anterior ankle pain in a group of athletes who were involved in competition sport. The promising clinical results confirm an effective way of treating soft-tissue and bony impingement. In addition, we recommend prior to surgery, an adequate course of non-operative treatment, including modifications in the exercise program and athletic activity.

Adult↗

PubMed2001

Human phosphatidylethanolamine-binding protein facilitates heterotrimeric G protein-dependent signaling.

In this study we report that human phosphatidylethanolamine-binding protein (hPBP) facilitates heterotrimeric G protein-coupled signaling. In Xenopus laevis oocytes, coexpression of hPBP with human mu opioid receptor, human delta opioid receptor, or human somatostatin receptor 2 evoked an agonist-induced increase in potassium conductance of G protein-activated inwardly rectifying potassium channels. This activation of heterotrimeric G protein signaling in oocytes could also be elicited by injection of bacterially overexpressed and purified hPBP. Stimulatory effect was pertussis toxin-sensitive and present even in the absence of coexpressed receptors. Additionally, an increase in G protein-mediated inhibition of adenylate cyclase activity, measured by the inhibition of forskolin-mediated cAMP accumulation, could be detected in HEK293 and NIH3T3 cells after expression of hPBP and in Xenopus oocytes after injection of hPBP. As [(35)S]guanosine 5'-3-O-(thio)triphosphate (GTPgammaS) binding to membranes prepared from hPBP-expressing cells was significantly elevated and recombinant hPBP dose-dependently stimulated [(35)S]GTPgammaS binding to native membranes, the results presented provide strong evidence that hPBP-induced effects are G protein-dependent. These data suggest a novel function of hPBP in regulating G protein and G protein-coupled receptor signaling in vivo.

3T3 Cells↗

PubMed2001

C-terminal splice variants of the mouse mu-opioid receptor differ in morphine-induced internalization and receptor resensitization.

The main analgesic effects of the opioid alkaloid morphine are mediated by the mu-opioid receptor. In contrast to endogenous opioid peptides, morphine activates the mu-opioid receptor without causing its rapid endocytosis. Recently, three novel C-terminal splice variants (MOR1C, MOR1D, and MOR1E) of the mouse mu-opioid receptor (MOR1) have been identified. In the present study, we show that these receptors differ substantially in their agonist-selective membrane trafficking. MOR1 and MOR1C stably expressed in human embryonic kidney 293 cells exhibited phosphorylation, internalization, and down-regulation in the presence of the opioid peptide [d-Ala(2),Me-Phe(4),Gly(5)-ol]enkephalin (DAMGO) but not in response to morphine. In contrast, MOR1D and MOR1E exhibited robust phosphorylation, internalization, and down-regulation in response to both DAMGO and morphine. DAMGO elicited a similar desensitization (during an 8-h exposure) and resensitization (during a 50-min drug-free interval) of all four mu-receptor splice variants. After morphine treatment, however, MOR1 and MOR1C showed a faster desensitization and no resensitization as compared with MOR1D and MOR1E. These results strongly reinforce the hypothesis that receptor phosphorylation and internalization are required for opioid receptor reactivation thus counteracting agonist-induced desensitization. Our findings also suggest a mechanism by which cell- and tissue-specific C-terminal splicing of the mu-opioid receptor may significantly modulate the development of tolerance to the various effects of morphine.

Alternative Splicing↗

PubMed1966