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B Ringe

Publications and source records attributed to B Ringe.

282 records · Page 16Linked to original sources

Safety and efficacy of living donor liver preservation with HTK solution.

BACKGROUND: In living donor liver transplantation (LDLTx) organ procurement is usually well controlled, and allows to assess liver preservation and graft function under standardized conditions. Because publications on histidine-tryptophan-ketoglutarate (HTK) solution are limited, we prospectively studied its safety and efficacy in a consecutive series of LDLTx. METHODS: Twenty-four patients received 22 right, 1 left, and 1 left lateral lobe graft. Liver preservation was done by gravity perfusion with HTK through portal vein, and hepatic artery, and flushing of bile ducts. Total ischemia time was 191 +/- 68 minutes. RESULTS: There was no primary nonfunction, and all partial liver grafts showed good recovery: peak aspartate aminotransferase 577 U/L, total bilirubin 15.15 mg/dL, and partial thromboplastin time 49.37 seconds. One graft was lost from parenchymal fracture secondary to portal hyperperfusion after 6 days, and the patient was salvaged with retransplantation. Thirty-day mortality, including sudden cardiac death, pancreatitis, and hepatic artery rupture, was not related to graft dysfunction. Eight of 24 recipients developed early biliary leakage. There was no late ischemic type biliary lesion. CONCLUSION: These results confirm that HTK solution is safe and effective when used in LDLTx. Potential advantages of HTK in comparison to other preservation solutions are low potassium concentration, low viscosity, no particles, in situ perfusion, no need to flush before reperfusion, improved biliary protection, better recovery of microcirculatory changes, ready to use, and lower costs. Because the risk-benefit ratio is of particular importance in LDLTx the use of HTK solution should be encouraged.

Adolescent↗

Four years' experience with cyclosporin A in pediatric kidney transplantation.

From 1982 to 1987 sixty-three children were treated with cyclosporin A and low dose prednisolone after kidney transplantation. Patient survival rate at 4 years after transplantation was 98.3%, survival rate of living related grafts 100% (n = 10), and survival rate of cadaveric grafts 73% (n = 53). Adequate cyclosporin blood levels were achieved in all children with a dosage regimen related to body surface area. Major concerns during the observation period were the loss of glomerular filtration rate from 51.8 to 40.5 ml/min/1.73 m2, a hypertension rate of 77.8%, and hyperuricemia. Cyclosporin A-side effects were mild. Infections occurred in 11.1%. Growth retardation in prepubertal children improved by 0.74 standard deviations of normal height, and in pubertal children by 0.51. We conclude that cyclosporin A treatment in children enables excellent long term graft survival rates with improved growth rehabilitation, however, the prevention of the cyclosporin associated nephrotoxicity and hypertension remains the major problem.

Adolescent↗

Radioimmunotherapy of colorectal cancer in small volume disease and in an adjuvant setting: preclinical evaluation in comparison to equitoxic chemotherapy and initial results of an ongoing phase-I/II clinical trial.

The 5-year survival of colorectal cancer patients with distant metastases is below 30%, despite the development and use of a variety of chemotherapeutic regimens. Therefore, new therapeutic strategies are warranted. Whereas radioimmunotherapy (RIT) has shown disappointing results in bulky disease, it may be a promising therapeutic alternative in limited and small volume disease. The aim of this study was, therefore, to compare, in a preclinical study, the therapeutic efficacy of RIT in colorectal cancer to equitoxic chemotherapy, as well as to evaluate, in a pilot clinical trial, its efficacy in small volume disease. Nude mice, bearing subcutaneous or metastatic human colon cancer xenografts, were injected either with the unlabeled or 131I-labeled monoclonal antibodies (MAbs), CO17-1A (which is a murine IgG2a directed against a 41-kD membrane glycoprotein) or F023C5 (which is an anti-CEA MAb of murine IgG1 subtype), or were administered 5-fluorouracil/folinic acid (5-FU/LV) at equitoxic doses. In a pilot clinical study, 10 colorectal cancer patients with small volume metastatic disease (all lesions < or = 3 cm) have been entered so far in an ongoing mCi/m2-based dose escalation study with the 131I-labeled F023C5. In the animals, the maximum tolerated activities (MTD) of 131I-labeled CO17-1A and F023C5 were 300 microCi and 600 microCi, respectively, corresponding to blood doses of approximately 15 Gy each. Accordingly, myelotoxicity was dose-limiting. The MTD in the chemotherapy group was 0.6 mg 5-FU/1.8 mg LV, given as intravenous bolus 1 h apart for 5 subsequent days. Whereas no significant therapeutic effects were seen with both unlabeled MAbs or 5-FU/LV chemotherapy, tumor growth was retarded significantly with both radiolabeled antibodies. In the metastatic model, chemotherapy prolonged life for only a few weeks, whereas RIT led to cures in 35-55% of the animals. As was the case in the animals, myelotoxicity seems to be dose-limiting in patients as well. Encouraging anti-tumor effects were observed, lasting for up to more than 12 months. These data suggest that radioimmunotherapy may be a viable therapeutic option in colorectal cancer patients with limited disease. Myelotoxicity is the only dose-limiting organ toxicity. Although most patients were treated below the MTD, anti-tumor effects are encouraging. Further studies are ongoing.

Animals↗

Tryptophan hydroxylase antibodies used in the diagnosis of carcinoid.

The expression of tryptophan hydroxylase, the rate-limiting enzyme in the biosynthesis of serotonin, is described in a case of a 35 year-old patient with metastatic jejunal carcinoid. Immunohistochemically, monoclonal anti-tryptophan hydroxylase antibodies positively identified liver metastases of a neuroendocrine tumor. The cellular distribution of tryptophan hydroxylase was restricted exclusively to the cytoplasm of carcinoid cells, where it was found in large amounts. By means of immunoblotting, anti-tryptophan hydroxylase antibodies detected in samples from carcinoid tissue two closely migrating polypeptide bands with molecular weights of 26 kDa and 29 kDa, respectively. These two protein bands appear to represent proteolytically degraded polypeptides, since tryptophan hydroxylase is known for its extreme unstability in vitro. In our case, the immunohistochemical and biochemical identification of tryptophan hydroxylase in liver lesions of a neuroendocrine tumor permitted the correct diagnosis of a metastatic carcinoid.

Adult↗