Search

Die Diagnose bei komplexen Fehlfunktionen des unteren Harntraktes wird durch das Korrelieren von klinischer Symptomatik mit urodynamischen Daten gestellt. Es ist unbestritten, dass die urodynamischen Parameter einen direkten Einblick in die Funktion im unteren Harntrakt erlauben. Doch um festzustellen, was pathologisch ist, muss vorher definitert werden, was ein Normalbefund ist.

The short-term effect of the glucose-controlled insulin infusion system (GCIIS) Biostator on metabolic and hormonal responses was studied in 10 non-obese subjects with glucose intolerance and insulin low response to glucose. Glucose tolerance characterized by means of a 2 h glucose infusion test (12 mg/kg/min) primed by i.v. injection of 0.33 g glucose/kg body weight was completely normalized by GCIIS. Results provide further support that normalization of glucose tolerance by means of GCIIS is accompanied by peripheral hyperinsulinaemia if compared with 33 non-obese healthy controls. Glucose-induced endogenous insulin secretion (C-peptide) was significantly reduced during the GCIIS study possibly due to inhibition of insulin secretion by exogenous insulin and/or by lower blood glucose concentration after normalization of glucose tolerance. Acute normalization of glucose tolerance in these patients failed to alter pancreatic glucagon, NEFA and glycerol responses but normalized paradoxical growth hormone response to glucose.

Using the micro-scale modification of a newly developed RIA kit for insulin, we established methods for the determination of free and total insulin in serum of insulin-treated diabetics. Precipitation with polyethylene glycol 6000 or acid alcohol extraction of sera was carried out to remove or to dissociate antibody-bound insulin. Both assays permit precise and accurate measurement of either serum insulin fraction. In 50 diabetic sera with tracer insulin binding of 0—97%, free (after equilibration of the sera at 37 °C) and total insulin levels as well as insulin antibody binding parameters were determined. There was a good correlation of free to total insulin levels with maximally 10-fold higher values of total insulin. Both free and total insulin were found to be correlated with the ability of the serum to bind insulin. In detail, binding affinities (i.e. the reciprocal of equilibrium dissociation constants) and binding site concentrations were evaluated which were shown to be positively correlated with free and total insulin levels as well. From these data we conclude that insulin antibodies in the serum may accumulate therapeutic insulin and function as a depot for delivering insulin in insulinopenic episodes (Keilacker et al., 1982 and 1986). Measurement of Insulin in Human Sera Using a New RIA Kit. 1. Insulin Determination in the Absence of Insulin Antibodies — Conventional Assay and Micro Modification

In this study the in vivo relevance of spleen cell anti-islet cytotoxicity measured in vitro was examined by transplantation of 1,200 syngeneic islets into the spleen of rats receiving 0.5 ml complete Freund's adjuvant (CFA) 24 h before 25 mg/kg body weight streptozotocin (STZ) was given. Control rats receiving CFA or STZ alone remained normoglycaemic whereas 12 out of 21 CFA/STZ-treated rats developed a severe hyperglycaemia after three combined treatments. After the first and second combined treatment splenocytes showed a significant cytotoxicity (p less than 0.01) against syngeneic islets measured by 51Cr-release. This cytotoxicity was not detectable after the third combined treatment. The CFA/STZ-induced diabetes with a residual pancreatic insulin content of only 5% was permanently reversed by intrasplenic islet isografts, but, surprisingly, syngeneic islets survived too, if transplanted at the time when an anti-islet cytotoxicity was measured in vitro. From our results we conclude that the polyclonal activation by complete Freund's adjuvant potentiates the beta cell-toxic effect of a low dose of streptozotocin and induced a transient splenocyte-mediated anti-islet cytotoxicity not recurrent after islet transplantation. Furthermore, our findings reveal a discrepancy between organ-specific immune reactions measured in vitro and those affecting the beta cells in vivo.

A sensitive and versatile radioimmunoassay (RIA) for insulin was established using human insulin standard, a specific guinea pig anti-insulin antiserum and rabbit anti-guinea pig serum. Radioiodination was performed according to a modified chloramine T method. Tracer preparations were used for as long as 6 weeks after iodination. The standard curve ranges from 0.044 to 1.2 nmol/l. The intra-assay coefficient of variation (CV) was 3-5% and the inter-assay CV was 6-9% in the optimal range between 0.4 and 0.9 nmol/l. The average recovery of human insulin added to plasma or serum samples was 100.2 +/- 2.0% (n = 38) and 100.1 +/- 1.9% (n = 42), respectively. In addition to human insulin, porcine, canine, rabbit and bovine insulin can also be determined but not rat or mouse insulin. The cross-reactivity of the antiserum with porcine proinsulin was found to be 40% on the molar basis. The range of mean fasting plasma insulin concentrations in healthy subjects and under various pathological conditions were estimated.

The specific genes causing type 1 diabetes susceptibility in any species are unknown. Serological HLA studies have shown susceptibility to type 1 diabetes is linked to HLA DR3 and DR4 allels, whereas DR2 and DR5 alleles contain protective elements. DR4 chromosomes can be divided into diabetes prone or resistant by restriction fragment length polymorphism analyses with cDNA probes for DQ beta-gene. No type 1 diabetes-specific environmental factors have been revealed to be convincingly implicated in human type 1 diabetes. Congenital rubella, by its lasting influence on T cells creates susceptibility to many organ-specific autoimmune diseases. Certain dietary proteins shown in BB rats as well as hyperglycemia during the prenatal period increase the later incidence of type 1 diabetes. Human type 1 diabetes results from a progressive probably autoimmune loss of the pancreatic beta cells. The immunologic hallmarks of type 1 diabetes is the lymphocytic infiltration of pancreatic islets, the hyperexpression of class I MHC on all islet cells and the abarrent class II MHC expression on beta cells within inflamed islets, the increased frequency of activated T cells in islet and circulation. It is generally accepted that cellular immunity plays the major role in the pathogenesis of type 1 diabetes. The heightened autoimmune reactivity being detectable during the preclinical period, lasting months to years, has been proved by antibodies directed against cytoplasmic islet cell antigens (ICA), beta cell surface antigens (ICSA), insulin (IAA), and with a lower frequency against non-islet cell antigens. The presence of IgG insulin autoantibodies and complement fixing ICA confers increased risk for future type 1 diabetes development in genetically predisposed individuals than the presence of either marker alone. For ICSA a more specific and quantitative assay is needed. 90% of children developing type 1 diabetes were detected positive for ICA and/or IAA. By the time of clinical onset if type 1 diabetes some 90% of the insulin secretory beta cell mass has already been destroyed. For this reason, new approaches are needed to address the causes of diabetes and not just the consequences. The development of insulin-dependent diabetes may be reversible, or even preventable by early detection coupled with the judicious use of immunotherapy.

For the purpose of monitoring the yield of the insulin extraction procedure from animal pancreas three methods of insulin determination were compared, i.e. the mouse convulsion test, a radioreceptor assay (RRA) on rat fat cells and a radioimmunoassay (RIA) which was especially laid out for high insulin concentrations. In samples containing actually insulin in general all three methods provided comparable results. Notable differences were only found in proinsulin-containing material. Because of its simplicity and high reproducibility as well as the good agreement of its results with those obtained with the other assays, the RIA turned out to be the most suitable assay. On the other hand, the RRA should be useful in detecting molecular differences between the investigated insulin-like preparations and standard insulin.

A radioimmunoassay for the detection of monoclonal islet cell antibodies was developed using rat insulinoma cells as antigen carriers and 125I-labeled affinity-chromatographically purified anti-mouse Ig antibodies for detecting cell-bound mouse Ig. Prior to the assay cells had been attached to glass tubes by poly-dimethyl-diallyl ammonium chloride thus allowing to perform the assay as easy as a solid-phase immunoassay. Incubation protocol and cell number were chosen to ensure a high sensitivity of the assay. Results compared well with immunofluorescence findings. Of seven monoclonal islet cell antibodies tested for crossreactivity only one was displaceable by islet cell surface antibodies from diabetic sera. This antibody was induced by immunization with human islets whereas all others were from mice which had been autoimmunized with streptozotocin and complete Freund's adjuvant.

Autoantibodies against insulin, C-peptide, and glucagon were determined by radio-binding assay in 63 new-onset Type 1 (insulin-dependent) diabetic patients as well as in 70 controls. Plasma peptide binding was determined by means of 125I-labeled peptides and charcoal-dextran separation technique. Binding values exceeding the mean plus three standard deviations of the controls were considered as antibody-positive. Sixteen patients (25%) were positive for IAA, as 6 (10%) were positive for CAA and 2 (3%) for GAA. Of all control subjects, none were positive for either IAA or CAA, whereas 2 (2%) had GAA. The mean 125I-glucagon binding in the patients' group was, however, slightly enhanced and could be suppressed to normal values by excess unlabeled glucagon. The presence of IAA and/or CAA was significantly associated with more severe symptoms at diabetes manifestation. These results indicate that in new-onset Type 1 diabetics autoimmunity arises against all the insular peptides tested but is predominantly directed against those antigens secreted from the beta cells. Nevertheless, extremely low-binding GAA seem to be common in these patients. The determination of IAA/CAA might be useful in detecting a possible heterogeneity of Type 1 diabetes with regard to its clinical mode of manifestation.

The presence of islet cell cytoplasmic antibodies (ICA) and islet cell surface antibodies (ICSA) at the time of diagnosis of type 1 (insulin-dependent) diabetes mellitus has been taken as evidence that autoimmune mechanisms are involved in the pathogenesis of the disease. The demonstration that ICSA in the presence of complement are preferentially lytic for beta-cells may be important in defining the role of these autoantibodies in the pathogenesis of type 1 diabetes. Because of the polyclonality of the immune response, the ICA and ICSA molecules of diabetic patient vary enormously in their binding parameters. For this reason we have generated monoclonal antibodies (MC-Ab) to islet cell antigens. In this study we investigate the effect of the two MC-Ab K28 A1 and K28 D6 resulted from the same fusion of the P3-X63-Ag8 murine myeloma cell line with the spleen cells of a Balb/c mouse immunized with rat islet cells on the hormone release of isolated rat islet in co-culture with the antibody-secreting hybridomas. The MC-Ab K28 D6 binds to both islet cell cytoplasmic and surface antigens, the K28 A1 is only reactive with cytoplasmic antigens. Surprisingly, in contrast to the monoclonal antibody K28 A1, K28 D6 enhanced the glucagon content and diminished the insulin secretion of the islets. Either the K28 D6 is directed to an epitope occurring on the beta- as well as alpha-cells or the antibody-mediated inhibition of the glucagon release results in a significantly reduced insulin secretion.

In human type 1 diabetes (T1D) autoantibodies to insulin precede clinical disease, while little is known about the contribution of insulin-specific T lymphocytes-in particular, T helper (Th) subsets. Here we have studied the in vivo primed cytokine response to preproinsulin in peripheral blood mononuclear cells (PBMCs) and two major Th cell subsets-CD45RO+ memory cells and CD45RA+ naive/resting cells-in 35 individuals with HLA-DRB1*04, DQB1*0302 diabetes risk marker: 12 patients with T1D, 12 autoantibody-positive (Ab+) individuals, and 11 healthy controls. Cytokine secretion (TNF-alpha, IFN-gamma, IL-2, IL-4, IL-5, and IL-10) was measured in the supernatants of the cultures stimulated with 21 overlapping preproinsulin peptides as well as proinsulin and insulin. In Ab+ individuals our results reveal higher IL-4 levels in CD45RO+ memory cells and higher IL-5 levels in CD45RA+ naive/resting cells, while higher IL-2 production was found in PBMCs. In contrast, in PBMCs of T1D patients higher IFN-gamma and IL-10 secretion was found. Our data delineate characteristic cytokine patterns in peripheral T lymphocytes from patients at different stages of the T1D development.

Antibodies, due to their high specificities and retention, represent potential beta cell imaging agents, however their slow clearance from the blood may preclude their use. Antibody fragments (Fabs) have much higher clearance and if they can be made with similar binding characteristics, would be more efficacious agents. An existing beta cell specific antibody (K14D10) and its Fab were evaluated with a previously developed screening assay. The Fab and the intact immunoglobulin (IgG) had similar affinities (6 - 20 nM), binding sites (300 000 - 700 000 sites/cell), and binding kinetics (t (1/2) = 8 - 18 minutes) for beta cells. However, the cellular specificity was far below the estimated requisite values needed to overcome the very low beta cell mass in the pancreas. The Fab cleared the blood twice as fast as the IgG, but did not preferentially accumulate into pancreas. Thus, generation of Fabs from IgGs with high beta cell binding and blood clearance appears feasible, but in order for molecules to be useful for tracking beta cell mass, antibodies of greater cellular specificity will have to be used.

Recent studies of rare cases of pT3a renal cell carcinoma extending directly into the adrenal gland showed worse survival than in other pT3a cases and recategorization as stage pT4 was suggested. We assessed the prognostic validity of a stage pT3a diagnosis based on perirenal fat infiltration.: The records of 1,794 patients with renal cell carcinoma who underwent surgical resection between 1975 and 2000 at our institution were analyzed retrospectively. Focusing on pT3a tumors, as defined by perirenal fat infiltration, numerous clinical and histopathological parameters were investigated by univariate and multivariate statistical methods with cancer specific survival as the primary end point.: We identified 237 of 1,794 patients with perirenal fat infiltration, classified as having pT3a disease. In patients with pT3a tumors tumor size was a significant parameter predicting survival. The most significant cutoff value for tumor size in pT3a disease was 7 cm. Patients with distant metastasis had a worse prognosis independent of T classification. Therefore, to assess the prognostic value of the current T classification in regard to T3a tumors we excluded patients with tumor stage cM+ for further subgroup analysis. Survival comparison of pT1 pNall, cM0 (744 of 1,794 cases) and pT3a pNall, cM0 7 cm or less (100 of 237) as well as pT2 pNall, cM0 (265 of 1,794) and pT3a pNall, cM0 greater than 7 cm (93 of 237) yielded similar results. After splitting pT3a into a modified T1/T2 classification a significant difference in 5-year survival analysis for a modified T1/T2 stage was found (pT1 plus pT3a less than 7 cm 90% vs pT2 plus pT3a greater than 7 cm 73%, p0.001). Subsequently multivariate analysis in all 1,794 patients showed that modified T stage was an independent significant predictor of cancer specific survival.: We suggest revising the current pT3a classification based on perirenal fat infiltration but rendering a modified pT1/pT2 classification, which resolves pT3a cases without the loss of prognostic validity. Perirenal fat infiltration should not be used to assign T category. Tumors directly infiltrating the adrenal gland should be reclassified as T4.

This study attempts to assess the prevalence of diabetes-associated autoantibodies in a general population in the northeastern part of Germany, with emphasis on autoantibodies against glutamic acid decarboxylase (GADA), protein tyrosine phosphatase (IA-2A), and insulin (IAA) by radioassays >/= 98th percentile, and AAbs binding on pancreatic sections (ICA) by immunofluorescence >/= 10 Juvenile Diabetes Foundation units. From a total of 11,840 schoolchildren tested for all four AAbs, 821 (6.9%) children were positive for single AAbs, whereas 83 (0.7%) had multiple AAbs. If the primary screening were performed by testing GADA/IA-2A/IAA, 94% of probands with single AAbs and all with multiple AAbs would be identified. The combinations of GADA/IA-2A, GADA/IAA, and IA-2A/IAA would identify 97.6, 98.8, and 85.5% of probands with multiple AAbs, respectively. Thus, combined AAb screening in the general population identifies those probands at risk for diabetes.

Purpose: Routine removal of the ipsilateral adrenal gland in patients with renal cell carcinoma who undergo nephrectomy has been a matter of dispute. In a retrospective study we screened for subgroups of patients with renal cell carcinoma from a large single center patient population who may have benefited from ipsilateral adrenalectomy. Materials and Methods: Radical nephrectomy was performed in 1,635 patients at a single institution between 1980 and 2000. A total of 1,010 patients underwent radical nephrectomy plus ipsilateral adrenalectomy, whereas in 625 no simultaneous adrenalectomy was performed. Numerous clinical and histopathological parameters were investigated by univariate and multivariate statistical methods for their predictive value in regard to cancer specific survival. Results: Metastases in the adrenal gland were found in 5.5% of patients (56 of 1,010) undergoing nephrectomy with adrenalectomy. Of 30 patients with adrenal metastasis and preoperative computerized tomography/magnetic resonance imaging 23 were found to have histological evidence of cancer, approaching a false-negative rate of 23.3%. All patients with false-negative computerized tomography/magnetic resonance imaging had a primary tumor of greater than 4 cm. Patients with adrenal metastases predominately had pT3 or greater tumor stage (82%). Cancer specific survival rates (75% vs 73% for adrenalectomy vs no adrenalectomy) and postoperative complications rates (7% vs 8%) did not differ significantly between the 2 groups. The prognosis in patients with a solitary adrenal metastasis (18 of 56) was more favorable than in patients with additional metastatic sites (38 of 56). Conclusions: Adrenal metastases from primary renal cell carcinoma were found significantly more often in patients with advanced tumor stages. Ipsilateral adrenalectomy should be recommended for all resectable renal cell carcinoma with a primary tumor of greater than 4 cm or with nonorgan confined tumor stages (T3 or greater) since a false-negative rate of about 20% can be expected with current imaging techniques.

Preproinsulin is a target T cell autoantigen in human Type 1 diabetes. This study analyses the phenotype and epitope recognition of preproinsulin reactive T cells in subjects with a high genetic risk of diabetes [HLA-DRB1*04, DQ8 with Ab+ (autoantibody-positive) or without islet autoantibodies (control subjects)], and in HLA-matched diabetic patients.A preproinsulin peptide library approach was used to screen for cytokine profiles and epitope specificities in human peripheral blood lymphocytes, and CD4(+)CD45RA(-) and CD4(+)CD45RA(+) T cell subfractions, representing memory and naive and recently primed T cells respectively.In CD4(+) T cell subsets we identified immunodominant epitopes and cytokine production patterns that differed profoundly between patients, Ab+ subjects and non-diabetic HLA-matched control subjects. In Ab+ subjects, a C-peptide epitope C13-29 and insulin B-chain epitope B11-27 were preferentially recognised, whereas insulin-treated Type 1 diabetic patients reacted to native insulin and B-chain epitope B1-16. In peripheral blood lymphocytes of Ab+ subjects, an increase in T helper (Th) 1 (IFNgamma, IL-2) and Th2 (IL-4) cytokines was detectable, wheras in CD45RA(+) and CD45RA(-) subsets, IL-4 and IL-10 phenotypes dominated, compatible with the contribution of non-CD4 cells to IFNgamma content. In insulin-treated Type 1 diabetic patients, naive and recently primed CD4(+) cells were characterised by increasd IFNgamma, TNFalpha, and IL-5.Our data show that T cell reactivity to preproinsulin in CD45RA subsets is Th2-dominant in Ab+ subjects, challenging the Th1 paradigm in Type 1 diabetes. Characteristic immunodominant epitopes and cytokine patterns distinguish diabetic patients and Ab+ subjects from HLA-matched healthy individuals. This could prove useful in monitoring of T-cell immunity in clinical diabetes intervention trials.

Um Hinweise fur eine mogliche pathologische Bedeutung niedriger Serumspiegel des Hormons Ostradiol (E2) beim Mann zu gewinnen, wurde eine Normalbereichsbestimmung bei 91 gesunden Mannern (Alter 20–75 Jahre) mit hohem und niedrigem Beschwerdeindex (klassifiziert nach testpsychologischem Fragebogen Beschwerdeliste B-L) vorgenommen. Die statistische Aufarbeitung beider Gruppen ergab jedoch bezuglich des E2 keine Signifikanz hinsichtlich des Alters oder des Beschwerdeindex, wahrend das gleichzeitig mitbestimmte Gesamttestosteron (T) mit dem Beschwerdeindex (p

The importance of ultrasonography in early detection of renal cell carcinoma was analyzed for 1854 patients, who were operated from 1975 to 1997. The 5-year survival rate of all patients amounts to 75%, the 10- and 20-year survival rate was 68% and 64%. While from 1975 to 1986 tumor symptoms like hematuria (30%), abdominal pain (19%) and palpable mass (3%) lead to diagnosis of renal cell carcinoma in 56% of all cases, there were only 26% from 1987 to 1997. 83% of asymptomatical tumors from 1987 to 1997 were accidentally detected by means of ultrasonography in a kidney independent examination. These tumors are significantly smaller (5.5 cm) than the tumors of symptomatical patients (7.8 cm) and show often a significantly lower local tumor stage, a better tumor grade, frequently lymph nodes, which are free of tumor infiltration and more rarely distant metastasis. The 5-year survival rate of patients with incidental tumors, detected by ultrasonography (82%) was significantly better (log rank < 0.001) in comparison with the symptomatical patients (72%). These results verify 1. The effectivity of ultrasonography in early diagnosis of renal cell carcinoma and 2. The advantage of survival on patients with early tumor detection. That's why asymptomatic patients, who selected under risk factors should be examinated by ultrasonography consistently too.

The composition of sesquiterpene hydrocarbons of distilled lime oils of different geographic origin was analyzed in detail. Gas chromatography on capillary columns of varied polarity was employed for the optimal separation of the components in GC/MS. This led to the unambiguous identification of a number of sesquiterpenes. α-Santalene, α-amorphene, epi-β-santalene, β-sesquiphellandrene, 4(14),7(11)-selinadiene and (E)-α-bisabolene were confirmed as so far unknown constituents of distilled lime oil. 4,7(11)-Selinadiene was isolated in NMR purity and unequivocally assigned within the sesquiterpene fraction.

Bisher stehen keine komplett inerten Biomaterialien zur Verfugung und es existiert kein universeller Test zur Objektivierung der Biokompatibilitat. Dies resultiert aus der individuellen Variabilitat des Empfangerorganismus, insbesondere hinsichtlich der entzundlichen Reaktionsbereitschaft. Auch nach Implantation von Gefasprothesen aus polymeren Biomaterialien kommt es zu einem chronischen Entzundungsprozes. Dieser fuhrt ursachlich durch Hydrolyse oder Autoxidation zur Biodegradation des Implantats. Mit unseren Untersuchungen galt es, eine moglicherweise bestehende, spezifische humorale Immunantwort nach Implantation von Segmenten einer kollagenimpragnierten Polyesterprothese (Dacron) in einem Tiermodell darzulegen. Balb/c-Mausen wurde am 1., 18., 38. und 290. Versuchstag ein Prothesensegment intraperitoneal implantiert. Die Bestimmung der Serumantikorper erfolgte mit einem modifizierten Enzymimmunoassay unter Verwendung der Prothese als Target. Spezifische Antikorper gegen Polymere wurden nach wiederholter Implantation bei allen Tieren bis zum 322. Versuchstag nachgewiesen. Dabei konnte eine Antikorperbildung gegen die Kollagenimpragnierung ausgeschlossen werden. Die Antikorperbildung wurde durch den Zusatz von komplettem Freund-Adjuvans in Verbindung mit der ersten Implantation verstarkt. Der Nachweis von spezifischen Antikorpern gegen Polymere konnte zukunftig ein Parameter zur Testung der Biokompatibilitat darstellen.

In the last years two European projects – DISTIMA and PANORAMA – were working on stereoscopic and three-dimensional (3-D) video. While DISTIMA made it possible to transmit stereoscopic video compatible to MPEG 2 in real time, PANORAMA develops a 3-D video system: viewpoint adaptive visualisation of scenes providing look-around-capability. This paper describes selected parts of the work performed in the two projects: the DISTIMA real-time hardware for the MPEG2 compatible transmission of stereoscopic video, the DISTIMA activities in the area of region and object-based stereoscopic coding, the PANORAMA real-time hardware development for 3-D video based on disparity estimation and disparity compensated interpolation of intermediate views and the PANORAMA software development for 3-D video based on 3-D reconstruction and 3-D computer graphics.

Laparoscopy and magnetic resonance imaging (MRI) are competetive tools in the diagnostic of non-palpable testis. Advantages and disadvantages of this methods will be demonstrate. 29 boys investigated for this indication with MRI. In case MRI failed to locate the testis laparoscopy was performed with a new miniaturized set of pediatric instruments (1.9 mm optic). The aim of laparoscopy was the identification of the spermatic duct and vessels and their topographic relation to the internal inguinal ring. All findings were verified by open surgical procedures. MRI revealed 10 inguinal and 7 abdominal testis. There was no false positive finding. In 12 boys MRI showed no testis. 4 cases were correct negative, 8 cases were false negative (32 %). In these 8 MRI-negative patients laparoscopy revealed 7 inguinal and 1 abdominal testis. The optical quality of the mini-telescope was sufficient for a 100 % correct diagnosis. Laparoscopy related complications did not occur. Laparoscopy proved to be a powerful low risk diagnostic method in non- palpable testis with high senitivity and specifity (100 % correct positive, 0 % false negative). Therefore lapraroscopy is recommended as primary diagnostic access for this indication. In the same anesthesia a optimal therapy is possible. Nevertheless a positive MRI-finding locates the testis reliably, whereas a negative finding always needs further exploration because testis might have been missed.

Autoantibodies to glutamic acid decarboxylase (GAD) are an important marker of the autoimmune-mediated beta-cell destruction in insulin-dependent (Type I) diabetes. However, these autoantibodies are also found in patients with Stiff-man syndrome (SMS) without onset of diabetes and some diabetic patients who initially present as non-insulin dependent (Type II) diabetes later becoming insulin-dependent, called as latent autoimmune diabetes in adults (LADA). To study the immune response to GAD in these LADA patients a competitive radiobinding assay based on murine monoclonal antibodies recognizing three different GAD regions was performed. The monoclonal antibodies against GAD recognize two different linear epitopes localized at the N- (amino acids 4-17) and C-terminus (amino acids 572-585) and one conformation-dependent epitope region (amino acids 221-442 IDDM-E1) known to be immunodominant for diabetes-associated autoantibodies. All LADA sera (20/20) reduced substantially the 125I-GAD binding of the monoclonal antibodies reactive with the conformation-dependent epitope region IDDM-E1 and only 20% of these sera additionally diminished the 125I-GAD65 binding by those monoclonals reactive with the both linear epitopes. The SMS sera completely abolished the GAD binding of all three monoclonals, reflecting a broader repertoire including an immune response against the IDDM-E1, a conformation-dependent GAD65 epitope region, also revealed if the SMS sera are diluted to equivalent antibody concentrations. In summary, our results show that diabetes-associated GAD autoantibodies even in adult patients with a late autoimmune process preferentially recognize a conformation-dependent middle GAD65 region. An immune response to all three GAD epitope regions is seldom in these LADA patients and only detectable in association with high antibody titres.

Current developments of object-based coders target small image formats, low bit-rate and videophone applications with head-and-shoulders scenes. An object-based coder which can be used for any type of scene and can provide better picture quality than MPEG-2 at the same bit-rate is proposed in this paper. It is a high-quality object-based coder which aims to introduce the concept of object-based coding in quality-picture applications. The coder uses motion and stereo information throughout for image analysis and synthesis, and object ordering. The coder can be extended to a stereoscopic coder with only minor modifications. Results using CCIR 601 stereoscopic image sequences shot within RACE DISTIMA are presented.

To study the immune response to glutamic acid decarboxylase (GAD) in insulin-dependent diabetes mellitus, monoclonal GAD antibodies after fusion of splenocytes from a nondiabetes-susceptible BALB/c mouse immunized with human recombinant GAD65 were generated. Of the 44 monoclonals, 35 are specific for the GAD65 isoform, whereas 9 also react with GAD67. Some 37 monoclonals, including all GAD65/67 reactive antibodies, react with GAD by Western blot analysis. The remaining 7 GAD65 monoclonals bind GAD only in an immunoprecipitation assay, which implies that they target epitopes dependent on the conformation of the GAD molecule. The 125I-GAD binding of the GAD65 monoclonals reactive on Western blotting was significantly diminished by all 3 sera from Stiff-man syndrome patients but only by 3/30 (10%) sera from type 1 diabetic patients. In contrast, the 7 monoclonal antibodies reactive with a conformation-dependent GAD epitope were competitive with 83% of GAD-autoantibody-positive sera from these diabetic patients. Using chimeric GAD65/67 proteins, the epitope region targeted by these monoclonals was mapped to the middle of GAD65 (amino acids 221-442). This central conformation-dependent GAD region was also targeted by sera from patients with type 1 diabetes. In conclusion, our data show that even after common immunization of a nondiabetes-susceptible mouse strain, monoclonal were obtained which preferentially react with the GAD65 linear amino-terminus (amino acids 4-17) and a conformation-dependent region located in the middle of GAD targeted by autoantibodies, indicating that this GAD region is not restricted to the autoimmune response associated with the Stiff-man syndrome and the beta-cell destruction in type 1 diabetes mellitus.

We report a case of primary renal osteosarcoma diagnosed during the patient's life. A review of the literature revealed only 10 cases of primary osteogenic renal sarcoma. Differential diagnoses and possible treatment are discussed.

Lühder F, Woltanski K-P, Mauch L, Haubruck H, Kohnert K-D, Rjasanowski I, Michaelis D, Ziegler M. Detection of autoantibodies to the 65-kD isoform of glutamate decarboxylase by radioimmunoassay. Eur J Endocrinol 1994:130:575–80. ISSN 0804–4643 Autoantibodies (AAb) to glutamate decarboxylase (GAD) occur with a high prevalence in sera of newly diagnosed type I (insulin-dependent) diabetic patients. The aim of this study was to establish a GAD-AAb radioimmunoassay using 125I-labelled GAD65 and to evaluate this assay in a cross-sectional study with newly diagnosed type I diabetic patients (diabetes duration < 6 weeks). Furthermore, subjects at high risk of developing type I diabetes and individuals suffering from other autoimmune diseases were examined in this assay. For GAD-AAb detection, 125I-labelled GAD65 was incubated with 10 μl of human serum overnight on ice. Thirty of 51 (59%) type I diabetic patients but none of the 54 healthy blood donors tested were found to be positive. A displacement step using 100 000 g supernatant from rat brain containing or not containing GAD showed the specificity of the binding of 125I-GAD65. Concerning the individuals at high risk of developing diabetes, 9/12 (75%) islet cell antibody (ICA)-positive non-diabetic and 4/34 (12%) ICA-negative subjects with metabolic abnormalities were GAD-AAb positive. These results show the association between type I (insulin-dependent) diabetes mellitus and the occurrence of GAD65-AAb, which possibly predicts a risk of developing the disease. F Lühder, Department of Immunochemistry, Institute of Diabetes "Gerhardt Katsch", Greifswalder Str. I la, D-17495 Karlsburg, Germany

The enzyme glutamate decarboxylase (GAD) is considered one of the major Beta cell antigens in Type 1 diabetes mellitus. The GAD autoantibody (GAD-AAb) prevalence in newly diagnosed Type 1 diabetic patients has been described up to 80%, depending on the detection method used. The aim of this study was to evaluate a simple, specific, and sensitive radioimmunoassay (RIA) method for detection of AAb against both isoforms of the enzyme, GAD65 and GAD67, in a cross-sectional study using sera from newly diagnosed Type 1 diabetic patients and in a longitudinal study using sera from prediabetic patients and individuals at risk of developing the disease. The 125I-labelled full-length human recombinant proteins of GAD65 and GAD67 expressed in SF9 cells were used as the antigen source. The prevalence of GAD65-AAb in newly diagnosed Type 1 diabetic patients was found to be 73% (112/153), in contrast to 19% (14/72) of GAD67-AAb. Only one patient produced AAb restricted to GAD67. Furthermore, GAD65-AAb could also be detected in 73% (11/15) of prediabetic patients (up to 122 months before clinical manifestation of the disease), whereas only 27% (4/15) of them were positive for GAD67-AAb. In the group at risk of developing Type 1 diabetes, these prevalences were 77% (10/13) and 46% (6/13), respectively. In all GAD67-AAb-positive patients investigated in the longitudinal study, AAb to GAD65 were detectable. In 47% of patients positive for both GAD65-AAb and ICA, the GAD65-AAb appeared by up to 46 months before the occurrence of ICA was detected. The data illustrated that GAD65 is the main immunogenic isoform of the enzyme in the preclinical and clinical stages. The RIA detecting AAb against this isoform may facilitate the screening for individuals at risk of developing the disease.

Enzymatically isolated smooth muscle cells of the corpora cavernosa obtained from open biopsies of 15 patients, clinically nonresponding to papaverine/phentolamine and prostaglandin E1 (PGE1) and classified by cavernosometry, were examined using the patch-clamp technique in the whole-cell configuration mode simultaneously monitoring the intracellular calcium concentration by means of the Ca(2+)-sensitive fluorescence dye FURA-II. It could be demonstrated that extracellularly applied PGE1 induces smooth muscle relaxation by inhibition of voltage-dependent L-type Ca2+ currents (58 +/- 8%). Compared to intact cavenous tissue (n = 5), the smooth muscle cells of 14/15 PGE1 nonresponders had no evidence of functional disturbance. Due to intact smooth muscle cells in most cases, etiology of venoocclusive dysfunction remains unclear.