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S Jonas

Publications and source records attributed to S Jonas.

At least 91 records · Page 5Linked to original sources
PubMed1998

[Differential diagnosis and therapy of benign liver tumors].

Hemangioma, focal nodular hyperplasia (FNH) and hepatocellular adenoma represent the most common and clinically relevant benign liver tumors. Improved diagnostic imaging procedures as well as the broad use of oral contraceptives resulted in an increased detection rate during the past 25 years. Focal liver diseases are primarily diagnosed by ultrasonography, while a specific diagnosis can be established by contrast enhanced magnetic resonance imaging. Hepatocellular adenomas should be resected, since they bear the potential of a malignant transformation as well as the risk of rupture and intraperitoneal hemorrhage. Conversely, a conservative approach is advocated for hemangioma and FNH. However, surgical procedures may be justified when a mass becomes symptomatic, and should be applied liberally when the diagnosis remains uncertain.

Adenoma, Liver Cell↗
PubMed1998

Orthotopic liver transplantation for hepatic associated metabolic disorders.

Hepatic associated metabolic disorders represent 5% of the indications for orthotopic liver transplantation (OLTX) according to the European Liver Transplant Registry. We studied the outcome of this group at our institution after OLTX and combined liver/kidney transplantation. Between September 1988 and January 1997, 837 OLTXs were performed in 735 patients. Patient survival and graft function at 1 yr were 91.3 and 86%, respectively. Thirty-nine OLTXs were performed in 38 patients (15 female/23 male, median age +/- SD: 35 +/- 14 yr, range 4-60 yr) due to liver associated metabolic disorders (4.7%). Indications included Wilson's disease (n = 14), alpha-1-anti-trypsin-deficiency (n = 7), hemochromatosis (n = 4), erythropoetic protoporphyria (n = 4), cystic fibrosis (n = 2), Crigler-Najjar syndrome type I (n = 1), glycogenosis type I (n = 1), ornithine-transcarbomylase-deficiency (n = 1). In addition 4 patients suffering from primary hyperoxaluria type I received combined liver/kidney grafts. Survival rate the 1 yr after OLTX and combined OLTX/NTX was 91.8%. Twenty patients received cyclosporin A (55%) and 17 patients tacrolimus (45%) as primary immunosuppression. The mean follow-up was 28.6 months (range 4-73 months). Two patients with hemochromatosis died 1 and 3 months after OLTX, respectively, from Aspergillus sepsis followed by multiorgan-failure. One patient died of malignant lymphoma 5 months after transplantation. One patient required retransplantation 2 months after OLTX following arterial thrombosis and ischemic type biliary lesion. One year after OLTX, all patients demonstrated good graft function, liver grafts (ALT 17.9 +/- 13.6 IU/L, bilirubin 0.8 +/- 0.3.mg/dl, thromboplastin time 94 +/- 15%), and combined liver/kidney grafts (creatinine 2.4 +/- 1.4 mg/dl). OLTX, respectively combined OLTX/NTX, represent a successful therapy for hepatic associated metabolic disorders. Survival rates and graft function are similar to those in liver graft recipients for established indications at our institution. OLTX seems to be an excellent treatment for hepatic based therapy resistant neurological disorders.

Adolescent↗
PubMed1998

A liver with polycystic liver disease as graft for orthotopic liver transplantation.

Donor organ shortage calls for widening of criteria for organ transplantation. In exceptional cases, even livers with macroscopic alterations may be accepted for transplantation. The case of a patient who received a liver graft from a donor with previously unknown adult polycystic degeneration is reported. The liver showed only small bilobar cysts with less than 10% of hepatic replacement and was successfully used for orthotopic liver transplantation. Two years after transplantation the patient is in good clinical condition and has returned to work.

Cysts↗
PubMed1997

Is low molecular weight heparin a neuroprotectant?

This communication reports the results of investigations on the effect of low molecular weight heparin (LMWH) on intraneuronal calcium release, and considers its possible relevance to the treatment of ischemic stroke. It previously was shown that intraneuronal injection of conventional heparin (MW 12,000) in vitro prevents glutamate-induced calcium release from intracellular stores through its blocking action on IP3 (inositol-1,4,5-triphosphate) receptors, and thus interferes with events occurring in the ischemic cascade. In the experiments reported herein, a LMWH of MW 4500 was shown to have these same effects when injected into a Purkinje cell in an in vitro cerebellar slice preparation, and also when administered externally (bath application). By contrast, conventional heparin works only when injected into the cell; bath application has no effect. The results are interpreted to mean that the larger conventional heparin molecule cannot pass through the cell membrane, while the smaller LMWH molecule does indeed enter the cell. In a clinical trial, LMWH begun within 48 hours of ischemic stroke onset in humans improved outcome at 6 months; conventional heparin given in a similar trial was without benefit. That one anticoagulant was beneficial while another failed suggests the possibility that the difference was independent of effect on the clotting system. The experimental data herein reported support the view that LMWH may benefit stroke victims by an action directly cytoprotective against the consequences of neuronal ischemia.

Animals↗
PubMed1997

Treatment of cyclosporine-related adverse effects by conversion to tacrolimus after liver transplantation.

BACKGROUND: Cyclosporine (CsA)-associated side effects include nephrotoxicity, hypertension, neurological disorders, and hyperlipidemia. A considerable share of early and long-term posttransplant morbidity is likely to be drug related. METHODS: In 31 patients with stable graft function, conversion from CsA to tacrolimus was implemented due to nephrotoxicity (n=19), hypertension (n=9), and neurological disorders (n=8). RESULTS: Three months after conversion, a response was evident in 26 patients (84%), whereas 5 patients (16%) were nonresponsive. In 13 of 19 patients (68%) suffering from nephrotoxicity, serum creatinine levels decreased significantly from 2.0+/-0.5 mg/dl to 1.5+/-0.4 mg/dl (P<0.005), whereas in 6 of 19 patients (32%) no improvement was observed. Antihypertensive therapy was reduced in six of nine patients and neurological disorders improved in six of eight patients. When analyzing all patients, average levels of cholesterol and triglycerides were significantly lower after conversion when compared with at the time of conversion (P<0.05) CONCLUSIONS: Conversion to tacrolimus reduced drug-related side effects in the majority of patients, while graft function remained stable. Conversion to tacrolimus may be considered for CsA-related side effects as a potential beneficial approach.

Adult↗
PubMed1997

De novo malignancies after liver transplantation using tacrolimus-based protocols or cyclosporine-based quadruple immunosuppression with an interleukin-2 receptor antibody or antithymocyte globulin.

BACKGROUND: Although conventional immunosuppression after liver transplantation consists of cyclosporine A (CsA), steroids, and azathioprine, recently introduced protocols entail CsA-based quadruple induction protocols or tacrolimus-based combinations. These protocols aim to reduce the rejection rate and the considerable morbidity related to the side effects of additional immunosuppressive treatment, but have not yet been analyzed regarding their long term de novo neoplastic risk. METHODS: From September 1988 to May 1994, 500 liver transplantations were performed in 458 patients. The median follow-up was 50 months (range, 0.3-97 months) for all patients. Conventional triple therapy was implemented in 25 patients, CsA-based quadruple induction therapy using an antilymphocyte globulin preparation (ATG) in 190 patients, an interleukin-2 receptor antibody (BT563) in 141 patients, and tacrolimus-based dual or triple immunosuppression in 102 patients. The different protocols were evaluated in four randomized and two nonrandomized prospective trials. RESULTS: De novo neoplasias were detected in 33 patients (7.2%) and were comprised of lymphomas (n = 7), skin malignancies (n = 8 lesions in 7 patients), intraepithelial neoplasias of the cervix uteri (n = 7), breast carcinoma (n = 3), lung carcinoma (n = 3), and other malignancies (n = 6). The incidence of de novo neoplasias did not differ in the different trial arms. Only a positive T-crossmatch and a low CD4+/CD8+ ratio in patients receiving CsA-based immunosuppression demonstrated a significant correlation with the development of a de novo tumor in a multivariant logistic regression analysis. CONCLUSIONS: The development of de novo neoplastic diseases after liver transplantation with the use of CsA-based quadruple induction protocols or tacrolimus-based regimens for immunosuppresion was assessed over the long term. Recently introduced immunosuppressive protocols did not alter the posttransplant de novo tumor rate. Patients with a low CD4+/CD8+ ratio during CsA-based therapy or a positive T-crossmatch were identified to be at an increased risk for the development of a de novo malignancy.

Antibodies, Monoclonal↗
PubMed1997

Chronically rejected rat kidney allografts induce donor-specific tolerance.

Previous studies on pathophysiological mechanisms of chronic graft rejection demonstrated the impact of both alloresponsiveness and nonspecific immunological events on the process. To study the role of alloantigen-specific factors further, we hypothesized an acceleration of chronic graft rejection after presensitization. Chronically rejected renal allografts in the established Fischer 344 --> Lewis rat model were replaced sequentially by native allografts of donor origin. Grafting of second allografts was performed 2, 4, 8, and 12 weeks after the original transplantation and followed long term. Second allografts demonstrated significantly ameliorated functional and structural alterations with few cellular infiltrates. These changes were independent from the time interval between first and second engraftment (2-12 weeks); immunosuppressive treatment after the second engraftment was not influential. The nonresponsiveness was not restricted to the second kidney allografts, as heart allografts of donor origin in these recipients also functioned indefinitely, whereas third-party grafts (Lewis x Brown Norway F1) and Fischer 344 heart grafts in untreated Lewis control rats were acutely rejected. Thus, donor-specific and tissue-nonspecific graft acceptance is achieved by second engraftment of donor-specific allografts in a model of chronic graft rejection. Those observations demonstrate the synergistic effects of alloresponsiveness and of the injured graft itself for the development of chronic graft failure.

Animals↗
PubMed1997

A prospective randomized trial comparing interleukin-2 receptor antibody versus antithymocyte globulin as part of a quadruple immunosuppressive induction therapy following orthotopic liver transplantation.

BACKGROUND: Quadruple immunosuppressive induction therapy has been shown to markedly reduce the incidence of acute rejection episodes without increasing the incidence of infectious complications after liver transplantation. However, the use of polyclonal antibody preparations (e.g. antithymocyte globulin [ATG]) is associated with side effects such as fever and tachycardia. To evaluate the efficacy and the safety of a monoclonal antibody directed against the interleukin-2 receptor (BT563) in comparison with ATG as part of a quadruple induction regimen, a prospective, randomized study was conducted. METHODS: Eighty consecutive adult recipients of primary orthotopic liver transplants were randomized to receive either BT563 (10 mg/day; days 0-12; n=39) or ATG (5 mg/kg/day; days 0-6; n=41) in addition to the standard immunosuppressive protocol consisting of cyclosporine, and prednisolone, and azathioprine. RESULTS: Patients treated with BT563 had a significantly lower incidence of steroid-sensitive rejection episodes (3 vs. 11; P<0.025) and also significantly fewer drug-related side effects (4 vs. 18, P<0.038) when compared with patients treated with ATG. The incidence of infectious complications was not different between the two groups. Patient survival did not differ significantly between the two groups (84.6% at 1, 2, and 3 years in the BT563 group and 90.2% at 1 year and 87.8% at 2 and 3 years for the ATG group). Analysis of graft function showed an advantage for the BT563 group in terms of postoperative bilirubin levels. However, no differences were observed in long-term follow-up between the two groups. CONCLUSIONS: Our results indicate that treatment with anti-interleukin-2 receptor antibody as part of quadruple induction therapy after orthotopic liver transplantation is safe and effective and shows fewer steroid-sensitive rejection episodes as well as fewer side effects when compared with quadruple induction therapy including ATG.

Adult↗
PubMed1997

p53 hot-spot mutational analysis in advanced Western gallbladder carcinoma.

In gallbladder carcinoma, studies on the prime target of genetic alterations and gene therapy in human gallbladder malignancies, the p53 tumor suppressor gene, have been focusing on this gene's immunohistochemical detection. From November 1991 to October 1993, seven patients suffering from gallbladder carcinoma underwent surgical resection. Cancerous and normal liver tissues were obtained immediately after surgery, snap-frozen in liquid nitrogen, and stored at -80 degrees C for immunohistochemistry and DNA isolation. Exons 5, 6, 7, and 8 of the p53 gene were completely sequenced following polymerase chain reaction (PCR) amplification of a 1574-bp fragment. Missense mutations were detected in the cancerous tissues of two patients: one transition each on codons 134 (Phe-->Leu) and 146 (Trp-->Arg). Immunohistochemical p53 staining was positive in the latter patient only. This is the first report on sequence analysis and mutagenesis of the p53 gene in Caucasian patients with gallbladder cancer. Both mutations were transitions and seem to represent a rather rare event. The possible impact of p53 mutagenesis on gallbladder tumorigenesis requires evaluation in larger studies.

Adenocarcinoma↗
PubMed1997

Female sex hormone receptor status in advanced hepatocellular carcinoma and outcome after surgical resection.

BACKGROUND: There is a limited amount of data regarding the estrogen receptor (ER) and progesterone receptor (PgR) status of hepatocellular carcinomas (HGCs), and the relationship between receptor status and clinicopathologic features of tumors has not been reported. METHODS: Between April 1992 and December 1993, cancerous tissues for cytosolic preparation and receptor quantification in a monoclonal solid-phase enzyme immunoassay were obtained from 28 patients undergoing resection, three patients with total hepatectomy and subsequent liver transplantation, and two patients suffering from nonresectable HCC. RESULTS: ER and PgR were detected in the HCCs of 13 (39%) and 6 patients (18%), respectively. A lower age was observed among the female patients whose receptor status was negative for ER or PgR or both, as compared with the respective receptor-positive groups. No significant differences with respect to tumor stage and grading could be observed. There was one perioperative death (3%). In patients undergoing curative resection, 1-year survival in the ER(+) group was significantly lower than in the ER(-) group (40% versus 79%, p < 0.05). The 2-year survival rates in the ER(+) and ER(-) groups were 40% and 71%, respectively. A comparable trend did not become evident for PgR(+) and PgR(-) patients. CONCLUSIONS: Our data suggest a negative effect of an ER(+) tumor on patient survival after curative resection of advanced HCC.

Aged↗
PubMed1997

Immunogenicity and protectivity of a new liposomal hepatitis A vaccine.

In this study we investigated a new liposomal hepatitis A vaccine (Epaxal) developed by the Swiss Serum and Vaccine Institute clinically and immunologically using a one dose priming schedule and a booster injection after 1 year. This vaccine contains formalin inactivated hepatitis A virus particles attached to phospholipid vesicles together with influenza virus haemagglutinin. Two doses of the vaccine were administered at months 0 and 12 in 117 volunteers. Blood samples were drawn at days-7, 14 and 28 and after 6, 12 and 13 months, local and systemic reactions were monitored by means of questionnaires. Immunogenicity was evaluated as usual by the determination of anti-HAV from the collected sera using the ELISA technique. In order to evaluate the protective efficacy of the vaccine induced antibodies a sample of 25 sera mainly from vaccinees showing low ELISA titres was additionally analysed by means of a virus NT. The vaccine was excellently tolerable and highly immunogenic. Seroconversion evaluated by ELISA was 97 and 99%, respectively, 14 and 28 days after the first dose and 100% after the second dose. NT titres were well correlated with ELISA titres and showed similar seroconversion rates even in the early phase of immunization. The results of this study show that with two doses of the liposomal hepatitis A vaccine administered at months 0 and 12 early protection within 14 days and long lasting immunity can be achieved.

Adult↗
PubMed1997

The status of p53 in the metastatic progression of colorectal cancer.

In order to investigate the role of TP53 in tumour progression and metastasis, we analysed 33 liver metastases of colorectal carcinomas and 19 primary colon carcinomas from the same hospital with respect to mutational changes, loss of heterozygosity and expression of the TP53 tumour suppressor gene. Direct sequencing of PCR products corresponding to the coding region of TP53 revealed that 13 of 19 primary tumours (68%) and 23 of 33 liver metastases (70%) had mutations in the TP53 gene. The distribution of mutations along the coding region of TP53 was similar in liver metastases compared to primary tumours. Thus, codon specificity did not seem to be a relevant factor and cells carrying specific TP53 mutations seem to have no selective advantage in the metastasising process. Comparing our data with the mutational spectra found in other countries did not reveal differences in the distribution of mutations along the coding region. Most of the metastases analysed showed loss of heterozygosity (LOH, 9 of 12 cases, 75%) and strong nuclear staining in immunohistochemistry (10 of 17 cases, 59%). Furthermore, with respect to mRNA expression levels, tumours carrying TP53 mutations showed significantly higher p53 mRNA levels compared to those without TP53 mutations. Thus, regulation of p53 mRNA levels seems to be subject to selection processes in tumourigenesis.

Chromosome Deletion↗
PubMed1997

Cardiovascular risk factors in long-term follow-up after orthotopic liver transplantation.

In a retrospective study the records of 302 adult patients (167 male, 135 female) after orthotopic liver transplantation (OLT) with a minimum follow-up of 6 months (median follow-up 18 months, maximum 5 yr) were reviewed with regard to cardiovascular risk factors. In 197 patients data concerning the occurrence of arterial hypertension, hyperglycemia, or hypercholesterolemia prior to OLT were available. We found a highly significant increase of cardiovascular risk factors following OLT. Obesity was found in 17.4% of male and 22.2% of female recipients after OLT. Hypercholesterolemia was evident in 66.2% of liver graft recipients. Hypertriglyceridemia occurred in 49.7% of all male patients. In females there was a significantly different prevalence of hypertriglyceridemia comparing patients with a follow-up period up to 2 yr and more than 2 yr (50% vs. 24.6%, p = 0.018). Nearly 45% of all patients met the criteria for arterial hypertension, with a slight increase in male patients beyond the second year of survival (p = 0.094). Hyperglycemia had a significantly higher frequency in male than in female patients (30.5% vs. 10.4%, p < 0.005). Furthermore we observed a clear trend towards reduction of occurrence of hyperglycemia more than 24 months after OLT, but not reaching statistical significance. No correlation was detected when serum levels of triglycerides, and cholesterol, body-mass-index, and arterial blood pressure were compared with applied dosages of immunosuppressive agents [cyclosporin A (CyA), tacrolimus, and prednisolone]. Only decreasing tacrolimus application was significantly correlated with decreasing glucosemia (p = 0.041). Patients receiving tacrolimus instead of CyA as primary immunosuppressant showed a significantly lower prevalence of hypercholesterolemia. Even hypertension, hyperglycemia, hypertriglyceridemia, and obesity had a lower occurrence in patients treated with tacrolimus although not reaching statistical significance.

Adolescent↗