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X Rogiers

Publications and source records attributed to X Rogiers.

At least 73 records · Page 4Linked to original sources
PubMed1999

Long-term insulin-secretory function of islets of Langerhans encapsulated with a layer of confluent chondrocytes for immunoisolation.

Islet transplantation is a potential cure for diabetes mellitus. The major problem for broad clinical application remains the prevention of transplant rejection without major side effects. Immunoisolation is an experimental strategy to prevent rejection by separating the transplanted cells from the host immune system using a barrier device. Current methods use artificial, not completely inert materials as barrier devices and induce an unwanted foreign-body (FB) reaction. Using the recipients of own cells for encapsulation, the FB reaction could be prevented. This study describes a new method of encapsulation of islets of Langerhans within a capsule of chondrocytes, which may serve as an immunoisolation barrier utilizing the immunoprivileged properties of the chrondrocyte matrix, and demonstrates the functional survival of the encapsulated islets in vitro.

Animals↗
PubMed1999

Heterotopic hepatocyte transplantation utilizing pancreatic islet cotransplantation for hepatotrophic stimulation: morphologic and morphometric evaluation.

Hepatocyte transplantation using three-dimensional (3D) matrices is under evaluation as an alternative therapy for liver diseases. It is known that hepatotropic stimulation optimizes hepatocyte engraftment. We investigated hepatotrophic stimulation by portocaval shunt operation (PCS) or pancreatic islet cotransplantation (ICT) over a period of 6 months. Lewis rats served as donors and recipients, respectively. One week prior to hepatocyte implantation PCS (group A) or a sham operation (groups B-D) was performed. Four polyvinyl-alcohol matrices, each containing 1.25 x 10(7) hepatocytes (groups A and C), 1.25 x 10(7) hepatocytes and 500 islets (group B), or cell-free culture medium (group D, control) were implanted between recipients' small-bowel mesenteric leaves. One, 3, and 6 months after implantation eight polymers from each group were harvested and analyzed by morphometry, PAS reaction, and immunohistochemistry for insulin, glucagon, and bromodesoxyuridine. Morphologically healthy-appearing hepatocytes were found in all cell transplantation groups at all times. Stimulation by either PCS or ICT significantly increased hepatocyte area at 1 and 6 months compared to unstimulated specimens (group C). Over time, an increase in hepatocyte area was noted in all groups. There were no significant differences in proliferation ratios between the three experimental groups. The initially reduced PAS reaction became normal after 3 months. 3D matrices provided a sufficient environment for transplanted hepatocytes and islets. Hepatocytes proliferated and maintained differentiation independent of hepatotrophic stimulation for at least 6 months when 3D matrices were utilized. ICT efficiently stimulated transplanted hepatocytes by means of hepatocyte area. These results justify further research on hepatocyte transplantation and ICT with regard to clinical application.

Animals↗
PubMed1999

Living-donor liver transplantation in children.

INTRODUCTION: Living-related liver transplantation (LRLT) for paediatric recipients was developed 10 years ago to overcome the high mortality on the waiting list. Since then, liver transplantation programs around the world have begun to employ this method with encouraging results. This review describes the actual status of LRLT in children, aspects of donor selection, donor risks, and surgical technique, as well as an update of the results of the leading LRLT programs in the world. The donor operation has matured to the stage of being a standardised, teachable procedure with a low risk of morbidity or mortality. However, there is a percentage of potential donations that have to be declined for medical or socio-psychological reasons. LRLT provides grafts of excellent quality and short cold ischemic times. A major advantage is the fact that the optimal moment for the transplantation procedure can be chosen. Together with split-liver techniques, LRLT has a positive effect on the general situation of the paediatric waiting list for liver transplantation, with a reduction of pre-transplant mortality to nearly 0%.

Child↗
PubMed1999

Interaction of hepatocytes and pancreatic islets cotransplanted in polymeric matrices.

Heterotopic hepatocyte transplantation (HcTx) in polymeric matrices may become an alternative to liver transplantation for metabolic disorders. Hepatotrophic stimulation by means of a portocaval shunt operation is an established, but invasive, procedure used to optimize hepatocyte engraftment in matrices. We evaluated hepatocyte and pancreatic islet cotransplantation (ICT) as an alternative noninvasive approach to hepatotrophic stimulation. Lewis rats served as donors and recipients. Hepatocytes and islets were isolated using collagenase digestion and seeded into polyvinylalcohol matrices. HcTx and ICT were compared with HcTx plus portocaval shunt and HcTx without stimulation. Matrices were investigated at 1, 3, and 6 months after implantation: the test methods applied were trichrome staining, PAS, immunohistochemistry for insulin, glucagon and incorporated BrdU, and in situ hybridization for albumin RNA. Hepatocytes expressed albumin RNA and formed conglomerates without atypias in all animals. ICT and portocaval shunting increased the number of hepatocytes and BrdU uptake. Alpha cells migrated into the islet-surrounding hepatocytes, whereas beta cells remained immobile. It is concluded that ICT and portocaval shunting supported engraftment of hepatocytes in polymeric matrices equally well. ICT did not interfere with recipient glucose metabolism and did not induce hyperproliferative premalignant foci within the transplanted hepatocytes. The technique is an attractive approach to hepatotrophic stimulation of bioartificial liver equivalents.

Animals↗
PubMed1999

Hemostasis with the ultrasonically activated scalpel. Effective substitute for electrocautery in surgical patients with pacemakers.

In patients with implanted pacemaker/cardioverter defibrillator (ICD), the use of electrocautery can lead to serious pacemaker dysfunction. The ultrasonically activated scalpel, however, which has been introduced mainly for the use in laparoscopic surgery, could potentially avoid the outlined problem, since no electrical current flows while in use. This hypothesis was tested in a pacemaker patient undergoing laparoscopic cholecystectomy. During the procedure, no abnormal rhythms or ECG interferences were detected while working in close vicinity to the device. Thus, the ultrasonically activated scalpel provides adequate hemostasis and does not bear the risk of pacemaker dysfunction.

Cholecystectomy, Laparoscopic↗
PubMed1999

Surgical treatment of chronic pancreatitis and quality of life after operation.

In conclusion, surgical therapy in patients with chronic pancreatitis may be characterized as follows: 1. Independently, several investigators have found intraductal and intraparenchymatous hypertension in patients with chronic pancreatitis. Decompression of the ductal system as the main principle of surgical therapy achieves clinical pain relief in most patients with chronic pancreatitis. The precondition is a consequent drainage of the main pancreatic duct and tributary ducts of second and third order up to the prepapillary region. The presence of an inflammatory tumor in the head of the pancreas or ductal abnormalities in the prepapillary region or a pancreas divisum requires performance of an extended drainage operation (LPJ-LPHE) to achieve pain relief and an improved quality of life. An extended drainage operation effectively manages complications arising from adjacent organs, such as distal common bile duct stenosis, segmental duodenal stenosis, and internal pancreatic fistulas. The extent of decompression has to be tailored to the anatomic and morphologic situation of the patient. 2. In patients with chronic pancreatitis, the main pancreatic duct is usually dilated. A small duct (3-5 mm) is only small for the surgeon. For the sclerosing entity of chronic pancreatitis with a truly small duct, that is, less than 3 mm in diameter ("small duct disease"), a longitudinal V-shaped excision of the ventral pancreas, as opposed to left resection, provides a new perspective for a sufficient drainage. 3. In the presence of segmental portal hypertension, a simple or extended drainage operation does not result in a normalization of the portal venous blood flow; however, how often relevant upper gastrointestinal hemorrhage develops from segmental portal hypertension is unclear. Therefore, the clinical relevance of this special problem needs further evaluation. 4. Postoperative morbidity of LPJ-LPHE is significantly lower in comparison to resectional procedures, such as PD, PPPD, and DPRHP. A lower perioperative mortality rate is not justified anymore as a relevant criterion in favor of drainage procedures because resectional procedures are burdened by a minimal or no mortality in experienced centers; however, PD and PPPD are greatly hampered by a significantly decreased postoperative global quality of life as opposed to the LPJ-LPHE. This is reflected by a significantly lower rate of social and professional rehabilitation. 5. The incidence of exocrine and endocrine organ dysfunction is lower after LPJ-LPHE compared with PD or PPPD, but not compared with DPRHP. Preservation of the gastroduodenal passage and the continuity of the bile duct with its associated feedback mechanisms of exocrine pancreatic secretion and glucose metabolism seem to be responsible for this phenomenon. 6. An early surgical or endoscopic interventional drainage of the hypertensive pancreatic duct system possibly offers the chance to favorably manipulate the natural course of chronic pancreatitis with regard to a delayed onset of exocrine or endocrine insufficiency. 7. Late mortality reflects continued alcohol abuse rather than the effect of an operative procedure.

Chronic Disease↗
PubMed1999

Systemic effects and side effects of interstitial techniques used in liver tissue.

BACKGROUND: Percutaneous ethanol injection (PEI) and cryosurgery are increasingly used for the treatment of liver malignancies. To create a safety margin and to destroy completely diffusely growing tumors, the precise destruction of healthy liver tissue is necessary. Little is known about the effects of operating on this type of tissue. This study evaluated the effects and side effects of PEI and cryosurgery when applied to normal parenchyma of the liver. STUDY DESIGN: Two groups of six minipigs each were treated with either PEI or cryosurgery to create necrosis in the liver. During and after the procedures, vital signs were monitored and necrotic areas were observed by ultrasonography. Standard and immunohistochemistry stains were made from samples of the necrosis, the liver, and the lung. RESULTS: In the PEI group, thromboembolic complications occurred in all animals (fatality rate 50%). Hematogenous spread of hepatocytes was demonstrated by immunohistochemistry and was a cause of pulmonary embolism. In the cryosurgery group, neither specific complications nor signs of cell spillage occurred. Because of an isolating effect of blood perfusion, hepatocytes close to the portal triads were less damaged, vital cells were present in the periphery, and the necroses were smaller than the induced lesions. CONCLUSIONS: The effect of PEI in healthy liver tissue is unpredictable. This makes the creation of a safety margin or the treatment of a diffusely infiltrating tumor impossible. PEI always introduces the risk of hematogenous cell spread. Effects of cryosurgery are less dependent on tissue qualities. In both techniques, the real extent of complete tissue destruction cannot be visualized by ultrasonography.

Animals↗
PubMed1999

Transmission of malaria tertiana by multi-organ donation.

In this report, transmission of malaria via a liver, a kidney, and possibly a heart allograft from a single donor is described. The donor had immigrated from Cameroon to Germany 18 months before, but had no clinical signs of active malaria infection. The liver transplant recipient and one of the two kidney transplant patients developed febrile illness with the appearance of Plasmodium vivax in blood smears 5 and 6 wk after transplantation, respectively. In the heart transplant recipient, a subclinical malaria infection was suspected based on a rise of malaria antibodies late after transplantation, whereas the recipient of the second kidney allograft had no clinical or laboratory evidence of malaria. Both liver and kidney recipients with active malaria responded to medical treatment. However, the liver transplant patient developed progressive cholestasis and died 5 months after transplantation from liver failure possibly due to side effects of the malaria medication. Other cases of malaria in solid organ recipients are briefly reviewed.

Adult↗
PubMed1999

Influence of pancreatic islets on growth and differentiation of hepatocytes in co-culture.

Improvement of cell culture conditions in hepatic tissue engineering may permit cell/tissue banking and the generation of liver tissue equivalents for transplantation. In these systems, continuous hepatotrophic stimulation is still necessary. We investigated the stimulatory effects of pancreatic islets on hepatocytes in co-culture and characterized the stimulatory mechanisms. Hepatocytes and pancreatic islets were harvested from Lewis rats. Cells were cultured on collagen dishes either with nonstimulated media (controls and co-cultures with low or high islet rate) or stimulated media (controls and co-cultures). To characterize stimulatory mechanisms, additional co-cultures with membrane separation, with antiinsulin, antiglucagon, and with both antibodies were examined. Hepatocyte numbers, albumin secretion rate by enzyme-linked immunoadsorbent assay, and monoethylglycinxylidid biotransformation values by fluorescence polarization immunoassay were assessed. A radioimmunoassay measured insulin and glucagon concentrations. In groups with nonstimulated media, cell number was higher in co-cultures with low islet rate, and albumin secretion rate was increased in co-cultures with high islet rate compared to controls. MEGX biotransformation was decreased in co-cultures. In groups with stimulated media, co-culture had no impact on cell number or albumin secretion rate. Hepatocyte numbers and albumin secretion rates were not changed in co-cultures after membrane separation. Islet effects on hepatocytes were reduced in co-cultures with antiinsulin, antiglucagon, or both antibodies. Pancreatic islets provide stimulation for hepatocytes in vitro. Islet effects were mediated by soluble factors, and are dependent on insulin and glucagon. These results permit further investigations towards three-dimensional transplantable hepatocyte-islet devices for continuous in vitro and in vivo stimulation.

Albumins↗
PubMed1999

Liver transplantation for acute liver failure.

Under conservative management, the mortality rate of acute liver failure is very high. Liver transplantation is an established life-saving therapy, offering survival rates between 60 and 90%. The decision for liver transplantation should be based on prognostic criteria, including patient's age, aetiology of liver disease, degree and onset of encephalopathy, serum bilirubin, prothrombin time or international normalized ratio (INR), serum creatinine, factor V level and arterial pH. Auxiliary liver transplantation is becoming an attractive treatment modality, allowing temporary bridging of liver function until recovery of the native liver. For children with acute liver failure, living related transplantation represents an additional option. In adult patients, living donation is not yet established since the maximum extent of liver resection safely tolerated and the amount of liver tissue necessary for sufficient graft function is still a matter of debate.

Adolescent↗
PubMed1999

Rupture of the spleen associated with Enterobacter cloacae.

A 58-year-old male, with abdominal pain but no signs of sepsis, was admitted as a medical emergency. During hospitalization, spontaneous splenic rupture was diagnosed and splenectomy successfully performed. A smear revealed presence of Enterobacter cloacae on the splenic surface; histopathology demonstrated granulocytous infiltration of the spleen.

Enterobacter cloacae↗
PubMed1998

[Is resection of colorectal liver metastases still justified in very elderly patients?].

Between 1987 and 1996 302 patients were treated for colorectal liver metastases. Out of this pool 252 completely documented cases were analysed. Forty-five patients (18%) of this population were 70 years or older at time of admission. In this population 17 major resections and 8 minor liver resections were performed. In 9 patients irresectable metastases were diagnosed during treatment of the primary tumor. In 3 cases laparotomy had to be finished as exploration. Eight patients were treated without surgery. Mortality after liver resection was 4%, morbidity 28%. The 5-year-survival-rate (Kaplan-Meier) of the R0 resected patients (n = 21) was 44%. Comparison between the elderly patients and the younger population shows no significant differences in type and extent of treatment or in stage of disease. Survival, morbidity and mortality after liver resection also show no significant differences. These results show that even in elderly patients liver resection for colorectal metastases can be performed efficently and with a curative intention.

Adult↗
PubMed1998

Treatment of liver metastases in patients with neuroendocrine tumors.

BACKGROUND: Hepatic metastases of neuroendocrine tumors demand differentiated therapeutic management due to the unique natural course and hormone secretion of the tumors. AIM: The purpose of the prospective nonrandomized study was to review the institutional experience with surgical treatment of hepatic neuroendocrine metastases. PATIENTS AND METHODS: From September 1992 until March 1996 29 consecutive patients with neuroendocrine tumors have been evaluated for surgical treatment of liver metastases. Of them, 11 (37.9%) fulfilled criteria for surgical treatment of hepatic secondary tumors. Extensive preoperative workup was carried out. Patients were divided in groups for curative or palliative resection. Liver transplantation was carried out in selected patients with disseminated liver metastases. RESULTS: Of 29 patients 4 (13.7%) underwent curative resection and in 3 patients (10.3%) palliative resection was performed. The patients who underwent curative resection are all biochemically and clinically tumor free at a mean postoperative follow-up of 22.3 months. Two patients who underwent palliative resection are alive at 40 and 29 months, respectively. From 12 patients evaluated for liver transplantation 4 were considered as suitable candidates. CONCLUSIONS: Liver resection can be recommended in patients with hepatic metastases of neuroendocrine tumors in terms of potential survival prolongation and palliation. Liver transplantation is generally acceptable treatment in highly selected group of these patients. Long-term results have to be awaited before definitive proof of the beneficial effect of surgical treatment.

Adult↗