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U T Hopt

Publications and source records attributed to U T Hopt.

At least 73 records · Page 4Linked to original sources
PubMed2001

Ischemia/reperfusion-induced pancreatitis in rats: a new model of complete normothermic in situ ischemia of a pancreatic tail-segment.

Ischemia/reperfusion injury plays an important role in the development of graft pancreatitis and thrombosis after pancreas transplantation. Up to now there are few therapeutic options for this severe complication because very little is known about pancreatic ischemia/reperfusion injury. The same pathomechanisms may also be involved in the induction and determination of the course of acute pancreatitis. We observed the effect of 2 h of warm in situ ischemia on the postischemic tissue oxygenation, histological organ damage, and pancreatic enzymes. Experiments were performed in 21 male Wistar rats. In sham-operated animals without ischemia, the pancreas was not dissected. In the ischemia/reperfusion group a pancreatic tail-segment was carefully separated from the head, and ischemia was induced by clamping the splenic vessels for 2 h, after flushing the pancreatic tail-segment with heparinized saline. Animals treated similarly, but with opening of the clamps some seconds after induction of ischemia, served as controls. The animals were observed for 2 h after reperfusion. Tissue oxygenation was monitored by a PO2-sensitive probe (LICOX, GMS, Kiel, Germany) which was implanted into the pancreatic tissue. Blood samples were taken before, 5 min, 60 min, and 120 min after reperfusion. At the end of the experiment the pancreatic tail was excised for histological examination; biopsies froin the non-ischemic pancreatic head served as intraindividual control to exclude side effects on the nonischemic pancreatic head. In the ischemia/reperfusion group, PO2ti was significantly lower 1 h (18.0+/-1.7 mmHg) and 2 h (16.4+/-1.6 mmHg) after reperfusion compared with baseline conditions (32.8+/-5.2 mmHg) and the control group (1 h 30.6+/-1.9 mmHg, 2 h 32.4+/-2.4 mmHg). Histological injury score and plasma lipase activity were significantly higher in the ischemia/reperfusion group compared with the control group. Thus we describe a new experimental model of complete normothermic in situ ischemia of a pancreatic tail-segment with the possibility of flushing the pancreatic tail-segment and selective local application of drugs to the pancreas.

Animals↗
PubMed2001

[Network of surgical wound centers using a new electronic data processing documentation system].

UNLABELLED: Care of chronic wounds is of enormous medical, social and economic importance. Nevertheless there is a lack of epidemiological and economical data. A network of ten wound care centers was created and data were documented in a new computerized wound documentation system. METHODS: Treatment was performed according to a comprehensive and standardized wound care protocol. The new documentation system is a network-capable solution. Digital images and planimetry as well as patient and wound related data are recorded. RESULTS: During the first year the ten centers treated and documented already 3281 wounds. There is a wide spectrum of different chronic wounds treated in the participating centers. Despite of long wound duration of several wounds with a median of 5 weeks (range 0-62 years), the healing rate was 80% within 455 days. CONCLUSION: Large amounts of data can be collected and scientifically evaluated in the wound net. This is realized by a new computerized documentation system, which was integrated into the clinical routine and enables clear and standardized documentation. Therefore even large multicenter therapy studies may be performed easily in the wound net and economical data could be collected.

Chronic Disease↗
PubMed2001

[Pyoderma gangrenosum after TAPP hernioplasty. A rare differential necrotizing wound infection diagnosis].

Pyoderma gangrenosum is an aseptic skin disease that occasionally complicates operative incisions and mimics postoperative necrotising wound infection. So far there are only a few case reports about bacterial necrotising infections following laparoscopy; no report exists about postoperative pyoderma gangrenosum after minimally invasive surgery. Differential diagnosis of both these diseases with potentially high morbidity and mortality is, however, essential, as they require opposite therapeutic regimens. Here we present the case of a patient who developed pyoderma gangrenosum after laparoscopic hernioplasty. Pathophysiological, clinical and therapeutic aspects of the disease are discussed.

Aged↗
PubMed2001

The penetration of ciprofloxacin into human pancreatic and peripancreatic necroses in acute necrotizing pancreatitis.

BACKGROUND: Antibiotic prophylaxis in necrotizing pancreatitis has recently gained acceptance. Published studies, however, used different antibiotic regimes and some antibiotics penetrated pancreatic tissue or pancreatic necroses only poorly. The aim of this study was to assess the penetration of ciprofloxacin (CIP) into necrotic pancreatic and peripancreatic tissue. PATIENTS AND METHODS: Serum, pancreatic necroses, peripancreatic fat tissue necroses and infected omental fluid levels of CIP were measured after 51 operations in 14 patients. RESULTS: The median penetration ratio of CIP was 137.5% (range 11-196%) in infected omental bursa fluid, 59.6% (3-214%) in pancreatic necroses and 67.1% (1-250%) in peripancreatic necroses. Chemotherapeutical ratios of CIP as a marker for antimicrobial potency were high against most relevant pathogens in necrotizing pancreatitis. CONCLUSION: Due to its antimicrobial spectrum and the good penetration into the relevant compartments, CIP may be useful in preventing local infection in necrotizing pancreatitis.

Adult↗
PubMed2001

[Distal pancreatic resection--indications, techniques and complications].

AIM: Description of the indications, surgical technique and postoperative complications of distal pancreatic resection. METHODS: We analyzed the prospectively documented perioperative data of 41 patients undergoing distal pancreatectomy between 1994 and 2001. Indications for resection were chronic pancreatitis (n = 21), malignant or benign tumors (n = 19) and others (n = 1). RESULTS: Median operation time was 4.5 hours, a Y-Roux-pancreaticojejunostomy was performed in 66 %. Further organs were resected in 93 %, most frequently in form of splenectomy. A malignant vascular invasion led to positive resection margins in three patients. Mortality was 2 %. Postoperative complications occurred in 41 % with 15 % revealing pancreatic leakage. A relaparotomy was carried out in 20 %. Pancreatic leakage was more frequently seen in the first part of the study period and after oversewing of the pancreatic stump. A new onset diabetes occurred postoperatively in 6 % of the patients. CONCLUSIONS: Distal pancreatectomy can be carried out with low mortality, despite a high complication rate. The probability of postoperative diabetes is low. The frequency of pancreatic leakage may be reduced significantly by increasing hospital experience. The management of the pancreatic stump by pancreatojejunostomy should be considered in patients with a high risk of pancreatic leakage.

Adenocarcinoma↗
PubMed2001

[Progress in operative techniques in pancreas transplantation].

Progress in operative techniques in pancreas transplantation.Pancreas transplantation has become a clinically established therapeutic procedure. The astonishing clinical success of pancreas transplantation resulted not only from new immunosuppressive strategies, but also from a remarkable progress in operative techniques. Pancreas segmental transplantation has been replaced by whole pancreas/duodenal transplantation. The exocrine secretion of the pancreas graft is not drained anymore into the bladder, but into the small intestine. Drainage of the venous blood from the graft containing high amounts of insulin is restored more and more not directly into the systemic venous circulation, but rather into the portal venous system. Thus, pancreas transplantation with enteral and portal drainage can be regarded as an operative technique which guarantees for the first time a totally physiologic situation in respect to the exocrine as well as endocrine secretions of the pancreas graft.

Duodenum↗
PubMed2001

p53 and K-ras mutations in pancreatic juice samples from patients with chronic pancreatitis.

BACKGROUND: Mutations in p53 and ras genes are frequent in pancreatic carcinoma. Several ras mutations are consistently detected in the pancreatic juice from patients with chronic pancreatitis. The p53 gene mutations have been detected occasionally in chronic pancreatitis tissue. It was the aim of this study to evaluate the presence and clinical significance of p53 and ras mutations in clinical pancreatic juice samples from patients with chronic pancreatitis. METHODS: Pancreatic juice was obtained from 66 patients with chronic pancreatitis and no evidence of pancreatic carcinoma (51 men, 15 women; age 17-86 years [mean 49.6 +/- 12.9]). Patients were followed prospectively for 26 +/- 3 (4-54) months. Detection of p53 gene mutations was by temperature gradient gel electrophoresis (TGGE) and single strand conformation polymorphism (SSCP) for exons 5-8. Analysis of ras mutations was performed by SSCP/polymerase chain reaction, restriction fragment length polymorphism/polymerase chain reaction. All mutations were confirmed by sequencing. RESULTS: Five of 66 (7.5%) pancreatic juice samples contained p53 mutations, and ras mutations were detected in 6 cases (9%). Cytology was negative in all cases. No pancreatic carcinoma developed during follow-up and neither cancer cells nor preneoplastic lesions could be detected histologically in resected specimens. Although no correlation between p53 mutations and duration of pancreatitis or drinking habits was found, K-ras mutations correlated with both heavy smoking and severity of the disease. CONCLUSION: p53 and ras mutations can be detected in a minority of pancreatic juice samples from patients with chronic pancreatitis in the absence of malignancy.

Adolescent↗
PubMed2001

[New developments in immunosuppressive therapy].

A highly effective immunosuppressive therapy with as few side effects as possible can only be achieved by a reliable drug monitoring. For neoral monitoring of the C2 level is essential while for tacrolimus measuring of the trough level is sufficient. Due to the different immunogenicity of the organ transplants the type and intensity of the immunosuppressive therapy should be organ-specific. Sirolimus is highly effective in combination with calcineurin antagonists in immunologically high-risk patients. In addition in case of severe side effects sirolimus can substitute for the calcineurin antagonists. Il-2 receptor antibodies are characterized by minimal side effects and have been shown to be a highly effective new therapeutic principle for immunosuppressive induction therapy.

Antibodies↗
PubMed2000

[First results of neoadjuvant simultaneious radiochemotherapy in advanced rectal carcinoma].

PURPOSE: In locally advanced rectal cancer tumor-negative margins often cannot be obtained by surgery alone. Nevertheless only patients with complete tumor resection can be cured. Due to the poor prognosis of patients with R1/R2 resection the "Deutsche Krebsgesellschaft" recommends concurrent preoperative radiochemotherapy for patients with locally advanced rectal cancer. PATIENTS AND METHODS: Between May 1997 and November 1999 22 patients were treated with preoperative radiochemotherapy. A total dose of 45 Gy with a small-volume boost of 5.4 Gy was delivered in conventional fractionation (single dose 1.8 Gy). On days 1 to 5 and 29 to 33 patients received concurrently 5-fluorouracil (5-FU) as continuous infusion of 1,000 mg/m2. If there was any sign of cardiac toxicity chemotherapy was changed to 5-FU/folinic acid or ralitrexed. RESULTS: Surgery following radiochemotherapy was performed in 19/22 patients. Resections with negative margins were achieved in 16/19 (84%) patients. Sphincter-conserving surgery was possible in 9/19 (47%) patients. A downstaging of at least 1 T category was found in 12/19 (63%) patients. With a median follow-up of 16 months no locoregional recurrences occurred in patients who underwent surgery. Two-year disease-free survival of resected patients is 62%, 2-year overall survival is 89%, of the whole population 76%. CONCLUSION: Preoperative radiochemotherapy followed by surgery is able to achieve clear resection margins in more than 70% of patients with locally advanced rectal cancer and may improve the rate of sphincter-conserving surgery.

Adult↗
PubMed2000

Pancreas organ transplantation. Short and long-term results in terms of diabetes control.

Diabetes mellitus is a very common and dreadful disease which cannot be cured by exogenous insulin substitution. Many of the patients suffer from recurrent, and sometimes rather dangerous, hypo- or hyperglycemias and, in the long term, from the well-known secondary diabetic complications. At the moment, pancreas transplantation is the only known therapy to reliably reestablish endogenous insulin secretion responsive to normal feed back controls. Within the last decade, pancreas transplantation has evolved as a clinically well-established procedure. Nevertheless, the perioperative risk after pancreas/kidney transplantation is still higher than after isolated kidney transplantation. However, the benefits of a functioning pancreas graft for the patients are enormous. Ten-year survival of type-I diabetic patients with combined pancreas/ kidney grafts is dramatically better than of those with an isolated kidney graft. Long-term function of the pancreas grafts is excellent, reaching more than 60% after 10 years. Contrary to kidney transplantation, chronic rejection does not seem to be a major problem. Blood glucose levels in the fasting state, after glucose challenge, and in the postprandial state are completely normalized. A significant peripheral hyperinsulinemia, however, is found when the pancreas graft is connected to the systemic venous circulation. Thus, portal venous drainage of the pancreas graft, which is already being performed by a few transplant centers routinely, might be the procedure of choice for the future. Beneficial effects on secondary diabetic lesions can only be expected after a rather long observation period. In addition, for all secondary diabetic complications, there is a point of no return. Nevertheless, significant improvement of diabetic polyneuropathy, diabetic nephropathy, and the disturbed microcirculation has been convincingly demonstrated. The effect on diabetic retinopathy, however, is still controversial. One of the most impressive effects for the pancreas graft recipients seems to be the enormous improvement in quality of life, which is reported unanimously by almost all patients. Thus, simultaneous pancreas/kidney transplantation can be regarded as the optimal and only causal therapy for type-I diabetic patients with end-stage renal disease.

Animals↗
PubMed2000

Liver support by extracorporeal blood purification: a clinical observation.

Liver failure associated with excretory insufficiency and jaundice results in an endogenous accumulation of toxins involved in the impairment of cardiovascular, kidney, and cerebral function. Moreover, these toxins have been shown to damage the liver itself by inducing hepatocellular apoptosis and necrosis, thus creating a vicious cycle of the disease. We report a retrospective cohort study of 26 patients with acute or chronic liver failure with intrahepatic cholestasis (bilirubin level > 20 mg/dL) who underwent a new extracorporeal blood purification treatment. A synthetic hydrophilic/hydrophobic domain-presenting semipermeable membrane (pore size < albumin size, 100-nm thick) was used for extracorporeal blood detoxification using dialysis equipment. The opposite side was rinsed with ligandin-like proteins as molecular adsorbents that were regenerated online using a chromatography-like recycling system (molecular adsorbent recirculating system [MARS]). Bile acid and bilirubin levels, representing the previously described toxins, were reduced by 16% to 53% and 10% to 90% of the initial concentration by a single treatment of 6 to 8 hours, respectively. Toxicity testing of patient plasma onto primary rat hepatocytes by live/dead fluorescence microscopy showed cell-damaging effects of jaundiced plasma that were not observed after treatment. Patients with a worsening of Child-Turcotte-Pugh (CTP) index before the treatments showed a significant improvement of this index during a period of 2 to 14 single treatments with an average of 14 days. After withdrawal of MARS treatment, this improvement was sustained in all long-term survivors. Ten patients represented a clinical status equivalent to the United Network for Organ Sharing (UNOS) status 2b (group A1), and all survived. Sixteen patients represented a clinical status equivalent to UNOS status 2a, and 7 of these patients survived (group A2), whereas 9 patients (group B) died. We conclude that in acute excretory failure caused by a chronic liver disease, this treatment provides a therapy option to remove toxins involved in multiorgan dysfunction secondary to liver failure.

Adult↗
PubMed1999

Critical islet mass for successful porcine islet autotransplantation.

A major reason for the failure of clinical islet transplantations may be a limited islet mass. The aim of this study was to determine the critical islet mass necessary for normalization of glucose metabolism in a porcine model. Diabetes was induced by total pancreatectomy. The splenic lobe of the pancreas was intraductally distended with UW-solution containing 2.67-3.33 mg/ml collagenase, and the distended pancreas was digested in a continuous digestion filtration device. The islets were purified on a isoosmotic Ficoll-sodium-diatrizoate gradient. The survival period of the diabetic recipients in group 2 and 3 receiving, respectively, a low (2.14+/-0.39 microL/kg body weight) and a high (4.99+/-0.83 microL/kg body weight) islet mass was significantly prolonged compared to that of diabetic recipients in group 1 receiving no islet transplantation. However, the survival period of the recipients in group 2 was not significantly different to that in group 3. Three recipients of an islet mass of >5 microl/kg body weight became normoglycemic (fasting blood glucose <100 mg/dl) for more than two months. Furthermore, the glucose and insulin release reactions to the glucose challenge were comparable to that before pancreatectomy. Contrarily, another five diabetic recipients of an islet mass of <4 microL/kg body weight became a fasting blood glucose level of <200 mg/dl. The glucose and insulin release reactions to the glucose challenge were improved only, but not normalized compared to that before pancreatectomy. The data presented in this study demonstrate that metabolic normalization in pancreatectomized diabetic minipigs can be established by autotransplantation of an islet mass of >5 microl/kg body weight.

Animals↗
PubMed1999

First clinical application of a newly developed device for intragastric surgery for the treatment of pancreatic pseudocysts.

BACKGROUND: Instruments that have been used during GI endoscopy have always been confined to the accessory channel of the endoscope. We have therefore developed a device that allows transabdominal manipulation in the stomach under gastroscopic control. Here we report the first clinical application of this device, which was used for the drainage of pancreatic pseudocysts. METHODS: The device is similar to a PEG tube and consists of a 7 mm polyethylene tube that is inserted by the "thread pull through" method. A trocar valve is mounted at the external tip of the tube. Four pseudocysts were treated in three patients. The retrogastric pseudocysts were punctured through the device under endoscopic (n = 2) and CT (n = 2) guidance. External drainage was used for 3 to 5 days; thereafter the drain was cut and internalized. The device was also cut and sealed. After 10 days it was removed as with a standard PEG tube. RESULTS: No complications related to the device occurred. In two patients the pseudocysts resolved completely. One patient had to undergo pseudocystojejunostomy for an infected pseudocyst containing large amounts of necrotic material. CONCLUSIONS: We believe that our new device is valuable to the further development of intragastric surgery and can be used to safely perform pseudocystogastrostomy.

Adult↗
PubMed1999

Differential gene expression after implantation of biomaterials into rat gastrointestine.

Two biodegradable materials, polyglycolide-copoly(L)-lactide/poly-dioxanone composite and poly(3-hydroxybutyrate), have been employed for surgery in the gastrointestine of laboratory rats. The tissue response was analyzed at distinct time intervals up to 2 months by differential mRNA display. Two specific PCR fragments were transiently present 7 and 14 days after contact with poly(3-hydroxybutyrate). Both fragments represent distinct rat lipases which might play a role in poly(3-hydroxybutyrate) degradation.

Journal Article↗
PubMed1999

Molecular adsorbent recycling system (MARS): clinical results of a new membrane-based blood purification system for bioartificial liver support.

The use of xenogenic or genetically engineered cell types in bioartificial liver support systems requires separation methods between the patients' blood and the liver support bioreactors that guarantee the sufficient transfer of pathophysiologically relevant substances but prevent complications. The present paper describes a new membrane separation system that is nearly impermeable to proteins but enables the exchange of water soluble and protein bound toxins by a special membrane and a recycled protein containing dialysate. Because the full range of toxins in hepatic failure has still not been identified, the value of this membrane separation method was evaluated clinically. Thirteen patients suffering from life threatening hepatic failure who had not responded to state of the art therapy were treated with this device, the molecular adsorbent recycling system (MARS). The overall survival rate was 69%. All patients showed positive response to the therapy, indicating that the presented membrane separator combines therapeutic effectivity with the highest safety criteria for the patient by cutting the exchange of substances below the level of proteins.

Adsorption↗
PubMed1999

[Secondary diabetes in pancreatic carcinoma and after pancreatectomy: pathophysiology, therapeutic peculiarities and prognosis].

Diabetes and pancreatic cancer are known to be associated. The relative risk for pancreatic carcinoma is dependent on the time after onset of diabetes. Diabetes in patients with pancreatic carcinoma is frequently of recent onset and partially caused by the tumor. Diabetes in a patient without obesity, no family history and unusual requirement for aggressive management including a rapid start of insulin treatment, may be early symptoms of pancreatic cancer. Recognition of atypical diabetes as an early symptom of pancreatic cancer may lead to earlier diagnosis and improved survival in these patients. Pancreatic carcinoma and chronic pancreatitis with untractable, incapacitating pain are the main reasons for (partial) pancreas resection. Pancreas resection may lead to a deterioration of pancreatic endocrine function. In healthy humans, hemipancreatectomy leads to impaired glucose tolerance after oral stimulation in 25% of the patients. To reduce morbidity resulting from operation, several operation techniques have been developed. Postoperative glucose metabolism is primarily dependent on the degree of preexisting endocrine function and on the amount of pancreatic tissue being resected. Early surgical intervention may, on the other hand, prevent the progression of endocrine insufficiency in the course of chronic pancreatitis. Good results of resective procedures now allow earlier operation. Any operative technique should aim on stopping the inflammatory process while preserving as much pancreatic tissue as possible. The choice of operation to be performed is dependent of morphological changes and individual local complications of the patient.

Diabetes Mellitus, Type 1↗