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J Klempnauer

Publications and source records attributed to J Klempnauer.

At least 127 records · Page 7Linked to original sources
PubMed1995

[Requirements for a surgical documentation system and its realization].

Adequate documentation of all surgical procedures is now essential. High demands in terms of quality and quantity mean that computerized databases and evaluation procedures are required. In the Department of Abdominal and Transplantation Surgery within Hanover Medical School a standardized but individually adaptable documentation system has been greated using standard hardware and software. A hierarchical code system has been established for surgical procedures, and this also offers the options of automatic online coding and translation into the coding used in the International Classification of Procedures in Medicine. The advantages and limitations of this system are discussed.

Database Management Systems↗
PubMed1995

Insulin and GLUT2 glucose transporter immunoreactivity in B-cells of whole pancreas isografts and allografts in the streptozotocin-diabetic rat.

The preservation of pancreatic B-cells is essential to ensure normal endocrine function of whole pancreas transplants. At present, however, it is unknown whether or not pancreatic B-cells in allografts display intercellular variations in insulin immunoreactivity and ultrastructure. It is also not clear whether the GLUT2 glucose transporter immunoreactivity is maintained in the plasma membrane after transplantation, as in B-cells under normal conditions. Therefore, pancreatic tissue of isografts and allografts, with or without signs of chronic rejection, was examined in streptozotocin-diabetic rats 10 to 100 days after transplantation by means of immunocytochemistry and electron microscopy. In isografts with preserved exocrine secretion pancreatic B-cells of larger islets exhibited normal heterogeneities in insulin immunoreactivity and in the number of secretory granules, whereas in isografts with suppressed exocrine secretion the heterogeneity was altered or abolished depending on the stage of islet dissociation. Differences in insulin immunoreactivity and ultrastructure were also observed in B-cells of tolerated allografts or those with signs of chronic rejection. In contrast to the localization of the GLUT2 glucose transporter under physiological conditions, GLUT2 glucose transporter immunoreactivity was not restricted to the pancreatic B-cell membrane but was also detected in the cytoplasm after transplantation. The cytoplasmic GLUT2 glucose-transporter localization developed in a time-dependent manner. It was evident 10 days after transplantation in isografts and was detectable still 100 days after transplantation in tolerated as well as in chronically rejected allografts. Interestingly, B-cells in the allografts with a dense insulin immunoreactivity exhibited GLUT2 glucose transporter expression in both localizations, whereas B-cells with a faint insulin immunoreactivity exhibited GLUT2 glucose transporter only in the plasma membrane. This may indicate a relation between the functional state of the pancreatic B-cells and the distribution of the GLUT2 glucose transporter in the cell. The heterogeneity between B-cells in pancreatic isografts and allografts implicates differences in the functional state of the B-cells with respect to insulin storage and release.

Animals↗
PubMed1995

Insulin cells in rat whole-pancreas isografts display heterogeneous immunoreactivities and ultrastructure.

It has already been shown that insulin cells studied under experimental conditions exhibit differences in insulin immunoreactivity and insulin release. The aim of this study, therefore, was to investigate whether insulin cells themselves exhibit morphological abnormalities after transplantation. Insulin cells in rat pancreas isografts with preserved or suppressed exocrine secretion were studied immunocytochemically and ultrastructurally and compared with those of unoperated rats. In isografts with preserved exocrine secretion, cortical insulin cells connected to the exocrine parenchyma or to glucagon or somatostatin cells expressed mostly dense immunoreactivities for insulin and amylin. In addition, medullary insulin cells connected only to other insulin cells displayed faint immunoreactivities for both constituents as found in unoperated animals. After duct ligation, however, pancreatic ducts and elongated capillaries extended into the islets. Corresponding to the stages of islet fragmentation, the heterogeneity among insulin cells underwent changes and was finally abolished. Ultrastructurally, differences in the number of secretory granules paralleled the heterogeneity in insulin immunoreactivity. It is interesting to note that the heterogeneity among insulin cells is preserved after transplantation, indicating that this phenomenon might be of physiological relevance. The heterogeneity may implicate differences in insulin storage and release as found in insulin cells under normal conditions.

Amyloid↗
PubMed1995

Back pain in patients with ductal pancreatic cancer. Its impact on resectability and prognosis after resection.

BACKGROUND: Back pain is a frequent and often ominous clinical sign in patients with ductal pancreatic cancer. METHODS: From 1971 to 1993 a pancreatic carcinoma could be resected in 192 patients, whereas 261 patients underwent either probatory laparotomy alone or palliative bypass procedures. In a retrospective study including uni- and multi-variate survival analysis we have determined the impact of preoperative back pain on both resectability and long-term prognosis after resection. RESULTS: Among the presenting symptoms of patients with ductal pancreatic cancer back pain was a predictive sign of irresectability. In the presence of preoperative back pain the long-term prognosis after resection of the tumour was also significantly impaired. In a multivariate analysis it could be demonstrated that the prognostic impact of back pain was as strong as the influence of residual tumour, tumour grading, and tumour size. CONCLUSIONS: Back pain often indicates irresectability of ductal pancreatic carcinoma and also impairs the long-term prognosis even after curative resection.

Adult↗
PubMed1994

[Symptomatic compression of the vena cava caused by a small liver hemangioma].

Occasioned by a recurrent urinary infection, ultrasonography was performed on a 41-year-old otherwise healthy woman. There were no abnormal renal findings, but a 4.5 x 4.5 cm space-occupying lesion with the echo-typical pattern of an haemangioma was found in the right lobe of the liver. Magnetic resonance imaging and dynamic computed tomography demonstrated compression of the vena cava by the tumour which was localized to the caudate lobe. The T2-weighed pictures suggested a cavernous haemangioma which extended from the vena cava at the diaphragm to the portal vein bifurcation. Obstruction to flow became evident 10 months later as oedema of the lower legs, giving the indication for surgical removal of the haemangioma. The benign tumour was enucleated under total vascular occlusion without significant blood loss pre- and post-operatively. The patient was discharged symptom-free on the 13th postoperative day.

Adult↗
PubMed1994

Genetic requirements for the development of the GVH reaction following small-bowel transplantation.

The genetic requirements for the development of graft-versus-host (GVH) disease have been investigated in a model of semiallogenic, heterotopic small-bowel transplantation in the rat. Following semiallogenic MHC-incompatible small-bowel transplantation, all graft recipients showed characteristic signs of GVH disease and died within 14 days. On autopsy the transplanted bowel was normal, while the recipient's bowel was dilated and distended with gas. Histology showed a generalized cell infiltration of the connective tissue with macrophages and lymphocytes. After semiallogenic, RT1.A-incompatible, small-bowel transplantation, the graft recipients developed mild and temporary symptoms of GVH disease between days 25 and 40. Only two of the six animals died, while the remaining animals survived the observation period. Small-bowel transplantation across an isolated RT1.C barrier was unable to induce GVH reaction. These results indicate that the development of GVH disease after small-bowel transplantation is controlled genetically by the MHC. Class II MHC incompatibility is necessary for the induction of an acute and lethal GVH reaction.

Animals↗
PubMed1994

Influence of formalin fixation on the detection of cytomegalovirus by polymerase chain reaction in immunocompromised patients and correlation to in situ hybridization, immunohistochemistry, and serological data.

The possibility of detecting cytomegalovirus (CMV) in formalin-fixed tissues by polymerase chain reaction (PCR) was evaluated in necroposies from lung tissues in a total of 24 patients who either had received organ transplants or were immunocompromised. PCR using two different pairs of primers for amplification of the major immediate early antigen of CMV was performed on fresh tissues and tissues fixed for 24, 48, and 72 h in neutral buffered formalin and compared to immunohistochemistry (IHC) and in situ hybridization (ISH). The fresh tissues of nine patients with serological evidence for acute CMV infection were all positive for CMV by PCR. After formalin fixation, the majority of the patients failed to show distinct signals with one or both pairs of primers as measured by densitometry. In contrast to this, fresh tissues of 15 patients without signs of an acute CMV infection were found either negative or weakly positive by PCR. Using IHC or ISH, positive results were observed only in five of nine and four of nine patients with acute CMV infection, respectively. These data demonstrate that, if only formalin-fixed tissue is available, PCR for CMV detection should be performed using two pairs of primers and should be supported by IHC.

Adolescent↗
PubMed1994

[Primary and secondary interventions--a concept in surgical documentation].

Nowadays systematic documentation of surgical procedures is absolutely necessary in all departments of surgery and will soon be required by law. Therefore code systems are essential. Amongst numerous systems the ICPM-GE classification has been chosen as basis. In the department for abdominal and transplantation surgery at Hanover Medical School the ICPM-GE classification has been extended by a concept of coding main and suboperations. This concept considers the fact that in an individual patient the surgical procedure may consist of different and standardized suboperations. This concept widens and simplifies the possibility of documentation considerably.

Cholecystectomy↗
PubMed1993

The role of histocompatibility antigens in transplantation of isolated islets of Langerhans in the rat.

In a model of congenic and intra-MHC recombinant rat strains, the differential role of various histocompatibility antigens in renal subcapsular transplantation of purified islets of Langerhans is evaluated. Class I MHC antigens of the RT1.A region, expressed on the endocrine cells of the islets themselves, do not induce graft rejection on their own. MHC class I antigens as encoded by the RT1.C region do not induce rejection either. MHC class II antigens as encoded by the RT1.B/D region are not expressed on the endocrine pancreas, not even during rejection. Although interstitial dendritic cells situated within the islets express these antigens, an isolated RT1.B/D incompatibility of islets is associated with prolonged survival in contrast to rapid rejection of fully MHC-mismatched grafts. Unlike other organs, islets matched for all MHC antigens, but incompatible at minor histocompatibility antigens, undergo rejection early after transplantation.

Animals↗
PubMed1993

Diagnostic value of color Doppler sonography in primary liver tumors--a trend study.

In order to investigate the diagnostic value in differential diagnosis of primary liver tumors, color Doppler sonography was used preoperatively in 30 patients. Without difference, tumor hypervascularization was found in patients with hepatocellular carcinoma (2 of 4), cholangiocellular carcinoma (4 of 4), hemangioma (3 of 8), focal nodular hyperplasia (8 of 8), adenoma (3 of 4), and neuroendocrine tumor (n = 1). No vascular signal could be detected in 1 case of adenomatous hyperplasia and 2 cases of hepatocellular carcinoma, one after previous chemoembolization. Hemangioma appeared hypo- or even avascular in 5 of 8 patients. Therefore, according to our experience, the yield of color Doppler sonography is rather low for differential diagnosis and prediction of the tumor dignity. With regard to the surgical procedure, valuable information about tumor extension can be obtained particularly in central lesions close to hilar structures or liver vein confluence. Further indications result from follow-up of tumor vascularization after chemoembolization and chemotherapy.

Adenoma, Liver Cell↗
PubMed1992

Differential response of kidney and pancreas rejection to cyclosporine immunosuppression.

Immunological interferences between kidney and pancreas transplants were investigated in a genetically defined rat model of combined kidney and pancreas transplantation. Kidney and whole-pancreas grafts were transplanted microsurgically either as individual grafts or in a combined technique. Whole pancreas grafts were grafted into streptozotocin diabetic recipients (55 mg/kg bodyweight i.v.) three days after induction of diabetes. The exocrine secretion was suppressed by duct ligation. Rejection of the grafts was defined by recurrence of diabetes in pancreas-grafted recipients and renal failure after kidney transplantation. There were marked differences in the efficacy of identical short-term cyclosporine immunosuppression (15 mg/kg intramuscularly for 14 days): DA kidneys survived indefinitely in LEW rats (MST greater than 100 days), while DA pancreas allografts underwent prolonged but not permanent survival (P less than 0.01) either as individual grafts (MST 27.3 +/- 1,9 days) or when transplanted simultaneously together with the kidney (44 +/- 16 days) (P less than 0.01). LEW rats carrying a DA kidney for 100 days also rejected a subsequent donor-specific pancreas transplant within 30 days. The histological alterations in the kidney were more pronounced than after cyclosporine-induced DA kidney long-term survival alone. By contrast to the rejecting subsequently transferred pancreas, a metachronous second DA kidney was permanently accepted (greater than 100 days) without further immunosuppression after removal of the first graft, while unrelated LEW. 1U kidneys were acutely rejected. In summary, the results indicate that there are not only quantitative differences of kidney and pancreas allograft survival but also differences concerning the state of immunological unresponsiveness induced by identical cyclosporine immunosuppression. While CsA induces donor-specific immunological unresponsiveness after kidney transplantation, pancreas transplants are all eventually rejected after some differential prolongation of survival. Further investigations on the effects of different MHC and minor alloantigens may provide more insight into the complex immunological situation of individual and combined kidney and pancreas transplantation.

Animals↗