Biomedical subjects

Jan M Langrehr

Publications and source records attributed to Jan M Langrehr.

At least 19 recordsLinked to original sources

PubMed2006

A randomized multi-center phase II trial of the angiogenesis inhibitor Cilengitide (EMD 121974) and gemcitabine compared with gemcitabine alone in advanced unresectable pancreatic cancer.

BACKGROUND: Anti-angiogenic treatment is believed to have at least cystostatic effects in highly vascularized tumours like pancreatic cancer. In this study, the treatment effects of the angiogenesis inhibitor Cilengitide and gemcitabine were compared with gemcitabine alone in patients with advanced unresectable pancreatic cancer. METHODS: A multi-national, open-label, controlled, randomized, parallel-group, phase II pilot study was conducted in 20 centers in 7 countries. Cilengitide was administered at 600 mg/m2 twice weekly for 4 weeks per cycle and gemcitabine at 1000 mg/m2 for 3 weeks followed by a week of rest per cycle. The planned treatment period was 6 four-week cycles. The primary endpoint of the study was overall survival and the secondary endpoints were progression-free survival (PFS), response rate, quality of life (QoL), effects on biological markers of disease (CA 19.9) and angiogenesis (vascular endothelial growth factor and basic fibroblast growth factor), and safety. An ancillary study investigated the pharmacokinetics of both drugs in a subset of patients. RESULTS: Eighty-nine patients were randomized. The median overall survival was 6.7 months for Cilengitide and gemcitabine and 7.7 months for gemcitabine alone. The median PFS times were 3.6 months and 3.8 months, respectively. The overall response rates were 17% and 14%, and the tumor growth control rates were 54% and 56%, respectively. Changes in the levels of CA 19.9 went in line with the clinical course of the disease, but no apparent relationships were seen with the biological markers of angiogenesis. QoL and safety evaluations were comparable between treatment groups. Pharmacokinetic studies showed no influence of gemcitabine on the pharmacokinetic parameters of Cilengitide and vice versa. CONCLUSION: There were no clinically important differences observed regarding efficacy, safety and QoL between the groups. The observations lay in the range of other clinical studies in this setting. The combination regimen was well tolerated with no adverse effects on the safety, tolerability and pharmacokinetics of either agent.

Adult↗

PubMed2006

Peroxisome proliferator-activated receptor gamma is highly expressed in pancreatic cancer and is associated with shorter overall survival times.

PURPOSE: Peroxisome proliferator-activated receptor gamma (PPARgamma) is a ligand-activated transcription factor that has been implicated in carcinogenesis and progression of various solid tumors, including pancreatic carcinoma. We aimed to clarify the expression patterns of PPARgamma in pancreatic ductal carcinomas and to correlate these to clinicopathologic variables, including patient survival. EXPERIMENTAL DESIGN: Array-based expression profiling of 19 microdissected carcinomas and 14 normal ductal epithelia was conducted. Additionally, Western blots of pancreatic cancer cell lines and paraffinized tissue of 129 pancreatic carcinomas were immunostained for PPARgamma. For statistical analysis, Fisher's exact test, chi2 test for trends, correlation analysis, Kaplan-Meier analysis, and Cox's regression were applied. RESULTS: Expression profiles showed a strong overexpression of PPARgamma mRNA (change fold, 6.9; P=0.04). Immunohistochemically, PPARgamma expression was seen in 71.3% of pancreatic cancer cases. PPARgamma expression correlated positively to higher pT stages and higher tumor grade. Survival analysis showed a significant prognostic value for PPARgamma, which was found to be independent in the clinically important subgroup of node-negative tumors. CONCLUSIONS: PPARgamma is commonly up-regulated in pancreatic ductal adenocarcinoma and might be a prognostic marker in this disease. Both findings corroborate the importance of PPARgamma in tumor progression of pancreatic cancer.

Adult↗

PubMed2006

Extended surgical resection for xanthogranulomatous cholecystitis mimicking advanced gallbladder carcinoma: A case report and review of literature.

Xanthogranulomatous cholecystitis (XGC) is a destructive inflammatory disease of the gallbladder, rarely involving adjacent organs and mimicking an advanced gallbladder carcinoma. The diagnosis is usually possible only after pathological examination. A 46 year-old woman was referred to our center for suspected gallbladder cancer involving the liver hilum, right liver lobe, right colonic flexure, and duodenum. Brushing cytology obtained by endoscopic retrograde cholangiography (ERC) showed high-grade dysplasia. The patient underwent an en-bloc resection of the mass, consisting of right lobectomy, right hemicolectomy, and a partial duodenal resection. Pathological examination unexpectedly revealed an XGC. Only six cases of extended surgical resections for XGC with direct involvement of adjacent organs have been reported so far. In these cases, given the possible coexistence of XGC with carcinoma, malignancy cannot be excluded, even after cytology and intraoperative frozen section investigation. In conclusion, due to the poor prognosis of gallbladder carcinoma on one side and possible complications deriving from highly aggressive inflammatory invasion of surrounding organs on the other side, it seems these cases should be treated as malignant tumors until proven otherwise. Clinicians should include XGC among the possible differential diagnoses of masses in liver hilum.

Cholecystitis↗

PubMed2006

Validation of cardiovascular risk scores in a liver transplant population.

Increased prevalence of cardiovascular risk factors has been acknowledged in liver transplant recipients, and an increased incidence of cardiovascular events has been suspected. Individual risk determination, however, has not yet been established. Outpatient charts of 438 primary liver transplants have been reviewed, and suspected cardiovascular risk factors were correlated with cardiovascular events observed during a follow-up period of 10 yr. Receiver operation characteristics curve (ROC) analysis was performed to validate established cardiovascular risk scores. For calibration, the Hosmer-Lemeshow test was performed. A total of 303 of 438 patients were available for risk factor analysis at 6 months and demonstrated complete follow-up data (175 male, 128 female). A total of 40 of those 303 patients experienced fatal or nonfatal cardiovascular events (13.2%). In univariate analysis, age (P < 0.001), gender (P = 0.002), body mass index (P = 0.018), cholesterol (P = 0.044), creatinine (P = 0.006), diabetes mellitus (P = 0.017), glucose (0.006), and systolic blood pressure (P = 0.043), but not cyclosporine A (P = 0.743), tacrolimus (P = 0.870), or steroid medication (P = 0.991), were significantly associated with cardiovascular events. Multivariate analysis, however, identified only age, gender, and cholesterol as independent predictors. In ROC analysis, corresponding areas under the curve for Systematic Coronary Risk Evaluation Project (SCORE), Prospective Cardiovascular Münster Study (PROCAM), and Framingham risk scores (FRSs) were calculated with 0.800, 0.778, and 0.707, respectively. Calibration demonstrated an improved goodness of fit for PROCAM compared to SCORE risk calculations. In conclusion, SCORE and PROCAM proved to be valuable in discriminating our liver transplant recipients for their individual risk of cardiovascular events. Furthermore, calibrated PROCAM risk estimates are required to calculate the number of patients needed to treat in the setup of prospective intervention trials.

Adult↗

PubMed2006

Jejunal loop drainage versus direct pancreatic duct drainage after pancreatic head resection.

PURPOSE: Perioperative mortality after pancreatic head resection has fallen to below 5% in high-volume centers, but dehiscence of the pancreatojejunostomy remains a major concern. Despite various methods of protection, insufficiency rates still range from 6% to 19%. External drainage of pancreatic juice from the anastomotic site has shown promising results in the last decade. We compared the morbidity and mortality of two widely used drainage systems. METHODS: The subjects were 143 patients who underwent pancreatic head resection, followed by jejunal loop drainage with the top of the drain being placed between the pancreatojejunostomy and hepaticojejunostomy in 89, and by direct drainage of the pancreatic duct in 54. RESULTS: The median age was similar in both groups. Pancreatic fistula developed in 3 (5%) patients with a pancreatic drain and 6 (7%) with a loop drain. Breakdown of the pancreatojejunostomy occurred in 1 (2%) patient with a pancreatic drain and 2 (2%) with a loop drain. The overall perioperative mortality was 0.7%. The surgical and medical complications and postoperative course were similar in the two groups. CONCLUSION: The choice of drainage system did not impact on the number or severity of postoperative complications or survival, indicating that loop drainage is as safe and effective as direct pancreatic duct drainage.

Adult↗

PubMed2005

Human hepatocytes are protected from ethanol-induced cytotoxicity by DADS via CYP2E1 inhibition.

We investigated the protective effects of diallyl disulfide (DADS), a potent inhibitor of cytochrome P450 2E1 (CYP2E1), on ethanol-induced toxicity in human hepatocytes. We found a clear dose-dependent response between ethanol and CYP2E1 activity. The ethanol-dependent CYP2E1 enzyme activity and protein expression, lactate dehydrogenase and aspartate transaminase release, malondialdehyde formation and caspase-3 activity decreased dramatically in the presence of DADS. Furthermore, DADS increased the hepatocellular glutathione (GSH) content and prevented the ethanol-dependent cellular GSH depletion. Our data show that DADS reduces ethanol-induced toxicity in human hepatocytes by reducing CYP2E1 activity and/or stabilizing the cellular GSH content, which might be of therapeutic interest.

Allyl Compounds↗

PubMed2005

Extended indications in living-donor liver transplantation: bile duct cancer.

The advantages of living donor liver transplantation are an individually available graft and a tremendously reduced waiting time until transplantation. One consequence is that many centers have extended the pretransplant selection criteria, especially for potential recipients suffering from hepatocellular carcinoma. In contrast, reports on living donor liver transplantation for cholangiocarcinoma are restricted to few case reports. We have analyzed our experience with seven patients suffering from cholangiocarcinoma (Klatskin tumors, n=5; intrahepatic cholangiocarcinoma, n=2). During a median follow-up of 20 months (range 2-46 months), all patients are alive except for one posttransplant death. Four patients suffering from Klatskin tumors are alive without recurrence; both patients suffering from intrahepatic cholangiocarcinoma are alive with bone and peritoneal metastases. Living donor liver transplantation may be beneficial in selected patients suffering from Klatskin tumors, whereas caution should prevail when considering intrahepatic cholangiocarcinoma.

Bile Duct Neoplasms↗

PubMed2005

Indications of mycophenolate mofetil in liver transplantation.

Mycophenolate mofetil (MMF) is approved for prophylaxis of acute rejection after kidney, heart, and liver transplantation as well as for pediatric patients after kidney transplantation. MMF, a noncompetitive inhibitor of inosine monophosphate dehydrogenase (IMPDH), blocks de novo purine synthesis which leads to an effective inhibition of proliferation selectively in T and B lymphocytes, smooth muscle cells, and fibroblasts. MMF shows additional effects with inhibition of the expression of activating and adhesion molecules on the surface of lymphocytes. The beneficial safety profile with distinct side effects compared to calcineurin inhibitors (CNI) enable efficacious combination with ciclosporin or tacrolimus as de novo therapy after liver transplantation. Furthermore, recent studies show the possibility to reduce CNI induced toxicities by adding MMF to primary immunosuppression. MMF is also used to enable early steroid withdrawal after liver transplantation. MMF can increase efficacy of immunosuppressive therapy and thereby support the treatment of steroid resistant acute rejections, chronic rejections and chronic graft dysfunction.

Adrenal Cortex Hormones↗

PubMed2005

Prospective randomized comparison between a new mattress technique and Cattell (duct-to-mucosa) pancreaticojejunostomy for pancreatic resection.

The majority of lethal complications after pancreatic head resection are due to septic complications after leakage from the pancreatojejunostomy. Especially the smooth pancreatic remnant is prone to develop parenchymal leaks from shear forces applied during tying of the sutures. We developed a new mattress technique that avoids such shear forces, and we compared this method to the standard Cattell (duct-to-mucosa) technique. A total of 113 patients undergoing standard pancreatic head resection were prospectively randomized to receive either the standard Cattell anastomosis (n = 56) or the new mattress technique (n = 57). All patients were evaluated for surgical and medical complications until discharge. Primary diagnosis and further demographic data compared well between the groups. The time to perform the mattress anastomosis was significantly shorter (15 vs. 22 minutes; p < 0.0001). The incidence of complications at the pancreatojejunostomy, and the length of hospital stay and survival were not significantly different between the two groups; however, a trend toward more reoperations was noted in the Cattell group (10 vs. 5; p < 0.097). The new mattress technique is simple, and our data show that the two techniques yield similar incidences of complications. Therefore the mattress technique for pancreatojejunostomy seems to be safe and is, in our opinion, well suitable for training schedules in pancreatic surgery.

Adult↗

PubMed2005

Arterial reconstruction in rat liver transplantation--development of a new tubing technique of the common hepatic artery.

Arterialization of liver transplants in rats results in an improved function compared with grafts without artery. Here we compared techniques of reconstruction, focusing on thrombosis, duration of procedure and severity of pancreas damage after dissecting the gastroduodenal artery (GDA). Group 1: tube was inserted into the proper hepatic artery (PHA) of donor and recipient. Group 2: tube was placed into common hepatic artery (CHA) of donor and recipient. Group 3: cuff was placed over the CHA of the recipient and the graft's artery was slipped over the cuff. Tubing in PHA leads to a thrombosis rate of 40% after 6 months. Arteries remain perfused by using a cuff or tube in CHA. Dissection of the GDA does not influence pancreatic perfusion. Reconstruction took 19 s using the large tube, about 30 s for the tube into PHA and 1 min for the cuff. The method of choice is using a tube for the CHA.

Animals↗

PubMed2005

Older liver graft transplantation, cholestasis and synthetic graft function.

Older liver grafts are often discarded because of conservative selection criteria. We report on our clinical experience with graft-age related outcome. Patients transplanted with livers older than 70 years (70.2-80.2 years, n = 38) were compared with controls transplanted with livers younger than 70 years. Pairs were matched for age, gender, indication and cold ischemic time. Mean donor age was 73.4 +/- 2 vs. 39 +/- 16 years. Patient and graft survival did not differ between both groups after 1-year follow-up (P = 0.19 and P = 0.24 respectively). Retransplantation rate was 10.5% vs. 5.3% (P = 0.40). Initial poor function occurred in two patients in the study group versus four patients in the control group (P = 0.69). The incidence of rejection episodes was comparable. Parameters of cholestasis and protein synthesis showed no difference 1-year post-transplant. Mean age of donor organs in matched pairs group B was near by half of that in the older donor group A (39.0 vs. 73.4 years). Post-transplant outcome as indicated by patient and graft survival was comparable between both groups. Donor organ age had no impact on postoperative organ function. We recommend to accept liver grafts from organ donors older than 70 years to expand the donor pool.

Adult↗

PubMed2005

Changing impact of cytomegalovirus in liver transplantation -- a single centre experience of more than 1000 transplantations without ganciclovir prophylaxis.

As cytomegalovirus (CMV) disease was a leading cause of death following liver transplantation in earlier reports, general CMV prophylaxis is widely used. We re-evaluated the impact of CMV in a recent time period under balanced immunosuppression and effective CMV diagnostics and therapy. A retrospective analysis of 1200 liver transplantations between 1988 and 2000 was performed comparing the incidence of CMV infection and disease and patient survival rates in two different time periods (before and after availability of the pp65-antigenaemia assay). In addition, risk factors for CMV in the recent time period were analysed. No ganciclovir prophylaxis was administered during the whole study period. The incidence of CMV tissue invasive disease decreased from 9.4% in period I to 2.7% in period II, whereas the incidence of viral syndrome was about 6% in both periods. Especially CMV pneumonia and generalized disease were almost abandoned in period II. Patients with tissue invasive disease, but not with infection or viral syndrome had reduced survival rates in both periods. However, the disease-specific mortality was 10% and 0% respectively. The overall rate of CMV infection in period II was low (25.9%). Risk factors for CMV infection in the univariate analysis were: Initial nonfunction, D+R- seroconstellation, acute liver failure, triple or quadruple immunosuppression, OKT3 or ATG treatment, transfusion of >10 packed red cells, steroid boluses, postoperative mechanical ventilation and retransplantation. In the multivariate analysis only quadruple or triple immunosuppression, OKT3-treatment, transplantation for acute liver failure and initial nonfunction. The incidence of CMV tissue invasive disease as well as the disease-specific mortality has markedly decreased during the last years. Using routine surveillance with the pp65-antigenaemia assay, CMV infection and disease rates compare well to data with long-term ganciclovir prophylaxis. As D+R- patients still more often develop symptomatic disease, pre-emptive therapy could be useful in this patient group.

Antibodies, Viral↗

PubMed2005

Supply of pre- and probiotics reduces bacterial infection rates after liver transplantation--a randomized, double-blind trial.

Bacterial infections frequently occur early after liver transplantation. We recently reported significant progress with a synbiotic composition, consisting of one lactic acid bacteria (LAB) and one fiber, which reduced the infection rate from 48% (with selective bowel decontamination) to 13%. Now, our aim is to study if a combination of different LAB and fibers would further improve outcome. A prospective randomized double-blind trial was undertaken in 66 liver transplant recipients. All patients received enteral nutrition immediately post-operatively. Comparison was made between one group (A) receiving a composition of four LAB and four fibers and another group (B) receiving the fibers only. The treatment started the day before surgery and continued for 14 days. Thirty-day infection rate, length of hospital stay, duration of antibiotic therapy, non-infectious complications and side effects of enteral nutrition were recorded. The incidence of post-operative bacterial infections was significantly reduced; being 48% with only fibers and 3% with LAB and fibers. In addition, the duration of antibiotic therapy was significantly shorter in the latter group. In both groups, mainly mild or moderate infections occurred. Fibers and LAB were well tolerated. Early enteral nutrition supplemented with a mixture of LAB and fibers reduces bacterial infection rates following liver transplantation. Treatment with only fibers led to a low incidence of severe infections.

Anti-Bacterial Agents↗

PubMed2005

MMF and calcineurin taper in recurrent hepatitis C after liver transplantation: impact on histological course.

Hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT) is almost universal. The optimal immunosuppression for these patients is still under discussion. We designed a retrospective case-control study to evaluate the effect of mycophenolate mofetil (MMF) treatment in patients with recurrent hepatitis C. Forty patients with histologically proven hepatitis C recurrence after OLT were treated with MMF and calcineurin inhibitor (CNI) taper for 24 months and matched with 40 non-MMF-treated positive liver transplant recipients. Liver biopsies were obtained prior to MMF treatment and after a mean follow-up of 24 months. Histological changes were evaluated utilizing the Metavir score. Comparison of fibrosis/inflammation showed no impairment of histological findings during MMF treatment. In contrast, histological findings of the 40 non-MMF patients showed a significant increase of severity for inflammation/fibrosis. Viral load was similar in both groups. The course of alanin amino transferase (ALT) levels measured during MMF treatment showed a significant decrease. MMF in combination with CNI taper showed a positive effect on fibrosis progression, graft inflammation and ALT levels and may improve the clinical course of HCV after OLT, however, the antiviral properties of MMF are still unconfirmed.

Calcineurin Inhibitors↗

PubMed2005

Hepatic resection in liver transplant recipients: single center experience and review of the literature.

Biliary complications such as ischemic (type) biliary lesions frequently develop following liver transplantation, requiring costly medical and endoscopic treatment. If conservative approaches fail, re-transplantation is most often an inevitable sequel. Because of an increasing donor organ shortage and unfavorable outcomes in hepatic re-transplantation, efforts to prolong graft survival become of particular interest. From a series of 1685 liver transplants, we herein report on three patients who underwent partial hepatic graft resection for (ischemic type) biliary lesions. In all cases, left hepatectomy (Couinaud's segments II, III and IV) was performed without Pringle maneuver or mobilization of the right liver. All patients fully recovered postoperatively, but biliary leakage required surgical revision twice in one patient. At last follow-up, two patients presented alive and well. The other patient with persistent hepatic artery thrombosis (HAT), however, demonstrated progression of disease in the right liver remnant and required re-transplantation 13 months after hepatic graft resection. Including our own patients, review of the literature identified 24 adult patients who underwent hepatic graft resection. In conclusion, partial graft hepatectomy can be considered a safe and beneficial procedure in selected liver transplant recipients with anatomical limited biliary injury, thereby, preserving scarce donor organs.

Adult↗

PubMed2004

Steroid administration before partial hepatectomy with temporary inflow occlusion does not influence cyclin D1 and Ki-67 related liver regeneration.

BACKGROUND AND AIMS: If temporary inflow occlusion is required during liver resection, the postoperative course might be complicated by ischaemia-reperfusion injury. Steroids protect against ischaemia-reperfusion injury; however, due to its anti-proliferative character concerns exist on its use on liver regeneration after resection. We investigated the effects of methylprednisolone on hepatocyte proliferation after partial hepatectomy with temporary inflow occlusion. PATIENTS AND METHODS: Prior to surgery, one group of Wistar rats received methylprednisolone, while a second group served as non-treated controls. Ischaemia-reperfusion injury was indicated by AST, ALT, and GLDH at 6 h after surgery. Immunohistochemistry tools were used to determine the mitotic index and Ki-67 expression, while cyclin D1 expression characterized the proliferative activity on days 1, 4, 7, and 10. RESULTS: The post-ischaemic liver enzyme release had significantly decreased in the methylprednisolone group, while expression of cyclin D1, percentage of Ki-67-positive cells, and mitotic cell index were comparable in both groups. Similar results were found for bilirubin and albumin and for weight of proliferating liver. CONCLUSION: Although steroid administration significantly reduced ischaemia-reperfusion-associated tissue injury, it has no apparent effects on hepatic regeneration. Thus, steroids could be recommended if a temporary liver ischaemia is required during surgery, in order to reduce complications caused by severe ischaemia-related organ dysfunction.

Animals↗

PubMed2004

Long-term outcome of liver transplants for chronic hepatitis C: a 10-year follow-up.

BACKGROUND: Recurrence of hepatitis C (HCV) infection after orthotopic liver transplantation (OLT) in HCV-positive patients is almost universal. Severity of graft hepatitis increases during the long-term follow-up, and up to 30% of patients develop severe graft hepatitis and cirrhosis. However, there are still no clear predictors for severe recurrence. The aim of this study was to examine the 10-year outcome and risk factors for graft failure caused by HCV recurrence. METHODS: In a prospective analysis, 234 OLTs in 209 HCV-positive patients with a median age of 53 years were analyzed. Immunosuppression was based on cyclosporine A or tacrolimus in different protocols. Predictors for outcome were genotype, viremia, donor variables, recipient demographics, postoperative immunosuppression, and human leukocyte antigen (HLA) compatibilities. RESULTS: Actuarial 5-, and 10-year patient survival was 75.8% and 68.8%. Eighteen of 209 (8.7%) patients died because of HCV recurrence, which was responsible for 35.9% of the total 53 deaths. Significant risk factors for HCV-related graft failure in an univariate analysis were multiple steroid pulses, use of OKT3, and donor age greater than 40. However, in a multivariate analysis, multiple rejection treatments with steroids and OKT3 treatment proved to be significantly associated with HCV-related graft loss. CONCLUSIONS: The analysis of causes leading to graft failure in patients with HCV showed that HCV recurrence is responsible for one of three deaths in HCV-positive patients. Rejection treatment contributed significantly to an enhanced risk for HCV-related graft loss. New antiviral treatments, as well as adapted immunosuppressive protocols, will be necessary to further improve the outcome of HCV-positive patients after liver transplantation.

Adolescent↗

PubMed2004

Fibrosis progression after liver transplantation in patients with recurrent hepatitis C.

BACKGROUND/AIMS: Aim of our study was to analyze fibrosis progression after liver transplantation (OLT) in hepatitis C virus (HCV)-infected patients based on protocol liver biopsies and to identify risk factors, which may play a role in the development of severe fibrosis stages. METHODS: One hundred and eighty-three liver graft recipients who had a histological follow-up evaluation of 1 year after OLT were analyzed. Overall 1039 protocol liver biopsies were performed after 1-, 3-, 5-, 7- and 10 years and staged according to the Scheuer score. RESULTS: The fibrosis progression rate was not linear. The fibrosis scores were 1.2 after one, 1.7 after three, 1.9 after five, 2.1 after 7 and 2.2 after 10 years. The 39 recipients with fibrosis stages 3 or 4 in the 1-year biopsy had a significantly reduced survival rate, while fibrosis stage 0-2 indicated excellent survival. Independent risk factors for progression of fibrosis at 1 year were HCV genotype 1 and 4 (P=0.01) and donor age>33 years (P=0.01), whereas risk factors for development of cirrhosis (30/183 recipients (16%)) were donor age (P=0.002) and multiple steroid pulses (P=0.05). CONCLUSIONS: These data provide information on the course of recurrent hepatitis C and may be helpful to individualize the treatment of transplanted patients.

Adult↗