Gastrointestinal stromal tumor in a patient with undiagnosed neurofibromatosis type I: an uncommon cause of extrahepatic cholestasis.

In this case report we present a 61-year-old patient with obstructive jaundice. Bile duct obstruction was caused by a tumor at the duodenal papilla and bile flow was restored by a plastic stent. Using endoscopic ultrasound and computed tomography imaging two additional tumors of the same morphology were found in the stomach wall and the pelvic region suggesting a multilocular gastrointestinal stroma tumor (GIST). Diagnosis of GIST was confirmed cytologically from the gastric lesion. Based on typical cutaneous manifestations (café-au-lait spots, several tiny dermal neurofibromata and Lisch nodules in the iris), a thus far unidentified neurofibromatosis type I was diagnosed which is known to promote multilocular GIST formation. Tumor resection failed because of cardiac decompensation due to a Takotsubo cardiomyopathy during induction of anesthesia. The patient has been started on imatinib instead and shows so far a stable disease over 6 months.

[Hereditary hyperferritinemia cataract syndrome--the first family in Germany]. / Das hereditäre Hyperferritinämie-Katarakt-Syndrom--die erste Familie in Deutschland.

We report on a 23-year-old woman who presented with elevated serum ferritin values at our department. She had undergone cataract surgery at the age of 14 and her family pedigree showed hereditary autosomal-dominant cataract. The combination of isolated hyperferritinemia with autosomal-dominant hereditary cataract led to the diagnosis of the hereditary hyperferritinemia cataract syndrome (HHCS) which we now describe in a German family for the first time. HHCS was confirmed by detection of a causal mutation at position 32 within the iron responsive element (IRE) of L-ferritin leading to a guanine to adenine exchange and the pathognomonic star-shaped cataract. This mutation interrupts the post-transcriptional control of L-ferritin. It prevents binding of the iron regulatory protein 1 (IRP1) to the 5alpha untranslated region of L-ferritin resulting in uncontrolled L-ferritin synthesis and high serum ferritin levels independent of the body iron stores. Premature cataract is eventually caused by deposition of L-ferritin crystals in the lens of the eye. Our family shows the typical autosomal-dominant inheritance of HHCS over four generations affecting a total of 17 family members. The causal mutation, star-shaped cataract and typical laboratory configuration were confirmed in five patients. Thus, in gastroenterological practice, HHCS should be added as a differential diagnosis of hyperferritinemia in Germany. Importantly, patients with HHCS can be spared from invasive diagnostics such as liver biopsy.

The GOX/CAT system: a novel enzymatic method to independently control hydrogen peroxide and hypoxia in cell culture.

The increasing demand in studying cellular functions in cultured cells under various levels of oxygen and hydrogen peroxide (H2O2) is only partly fulfilled by conventional approaches such as hypoxia chambers, bolus additions of H2O2 or redox-cycling drugs. This article describes the recently developed enzymatic GOX/CAT system consisting of glucose oxidase (GOX) and catalase (CAT) that allows the independent control and maintenance of both H2O2 and hypoxia in cell culture. In contrast to hypoxia chambers, the GOX/CAT system more rapidly induces hypoxia within minutes at a defined rate. The degree of hypoxia is dependent on the GOX activity and the diffusion distance of oxygen from the medium surface to the adherent cells. In contrast, H2O2 levels are solely controlled by the ratio of GOX and CAT activities. They can be adjusted at non-toxic or toxic dosages over 24 hours. Thus, the GOX/CAT system mimics a non-phosphorylating respiratory chain and allows to adjust H2O2 levels under hypoxic conditions truly simulating H2O2 release e.g. by inflammatory cells or intracellular sources. GOX/CAT can be employed to address many questions ranging from redox signaling to ischemia/reperfusion studies in transplantation medicine. Factors such as HIF1 alpha that respond both to hypoxia and H2O2 are an especially attractive target for the novel methodology. Several applications are discussed in detail to demonstrate the technical requirements and potentials. In addition, simplified protocols are presented for cell or molecular biology labs without dedicated biophysical equipment.

A new ensemble-based algorithm for identifying breath gas marker candidates in liver disease using ion molecule reaction mass spectrometry.

MOTIVATION: Alcoholic fatty liver disease (AFLD) and non-AFLD (NAFLD) can progress to severe liver diseases such as steatohepatitis, cirrhosis and cancer. Thus, the detection of early liver disease is essential; however, minimal invasive diagnostic methods in clinical hepatology still lack specificity. RESULTS: Ion molecule reaction mass spectrometry (IMR-MS) was applied to a total of 126 human breath gas samples comprising 91 cases (AFLD, NAFLD and cirrhosis) and 35 healthy controls. A new feature selection modality termed Stacked Feature Ranking (SFR) was developed to identify potential liver disease marker candidates in breath gas samples, relying on the combination of different entropy- and correlation-based feature ranking methods including statistical hypothesis testing using a two-level architecture with a suggestion and a decision layer. We benchmarked SFR against four single feature selection methods, a wrapper and a recently described ensemble method, indicating a significantly higher discriminatory ability of up to 10-15% for the SFR selected gas compounds expressed by the area under the ROC curve (AUC) of 0.85-0.95. Using this approach, we were able to identify unexpected breath gas marker candidates in liver disease of high predictive value. A literature study further supports top-ranked markers to be associated with liver disease. We propose SFR as a powerful tool for biomarker search in breath gas and other biological samples using mass spectrometry. AVAILABILITY: The algorithm SFR and IMR-MS datasets are available under http://biomed.umit.at/page.cfm?pageid=526.

Coil embolization of internal mammary artery injured during central vein catheter and cardiac pacemaker lead insertion.

PURPOSE: This study describes several cases of endovascular coil embolization of the proximal internal mammary artery injured by blind approach to the subclavian vein for central venous catheter or pacemaker lead insertion. MATERIALS AND METHODS: We conducted a retrospective analysis of five patients with iatrogenic arterial lesions of the internal mammary artery (IMA). The lesions occurred in three patients from a puncture of the subclavian vein during insertion of a central venous catheter and in two patients from a puncture of the subclavian vein for insertion of a pacemaker lead. Four patients had acute symptoms of bleeding with mediastinal hematoma and hematothorax and one patient was investigated in a chronic stage. A pseudoaneurysm was detected in all five patients. All four acute and hemodynamic unstable patients required hemodynamic support. RESULTS: In all patients, embolization was performed using a coaxial catheter technique, and a long segment of the IMA adjacent distally and proximally to the source of bleeding was occluded with pushable microcoils. In one patient, additional mechanically detachable microcoils were used at the very proximal part of the IMA. Microcoil embolization of the IMA was successful in all patients, and the source of bleeding was eliminated in all patients. CONCLUSION: Transarterial coil embolization is a feasible and efficient method in treating acute bleeding and pseudoaneurysm of the IMA and should be considered if mediastinal hematoma or hemathorax occurs after blind puncture of the subclavian vein.

Direct interaction of the extracellular matrix protein DANCE with apolipoprotein(a) mediated by the kringle IV-type 2 domain.

Lipoprotein(a) [Lp(a)] consists of LDL and apolipoprotein(a), and has been shown to be a major, independent, risk factor for arteriosclerosis and thrombosis in humans. To further elucidate the (patho)physiological function(s) of Lp(a)/apo(a), we searched for new protein ligands, using the yeast two-hybrid system and employing the highly repetitive kringle IV type 2 (KIV-2) sequence from apo(a) as bait. The extracellular matrix protein DANCE [developmental arteries and neural crest epidermal growth factor (EGF)-like] recently implicated in atherogenesis was identified as an interactor. A direct physical interaction between DANCE and apo(a) was confirmed by co-purification of both recombinant proteins derived from culture supernatants of transiently transfected COS-1 cells. Furthermore, binding of human plasma-derived Lp(a) to recombinant DANCE was also observed. Finally, when monoclonal anti-apo(a) and polyclonal anti-DANCE antibodies were applied to tissue slices of atherosclerotic carotid artery, the two proteins were found to be co-localized in endothelial and smooth muscle cells, suggesting that they occur together in the arterial wall. However, as yet, the in vivo relevance and the possible functional role of this newly identified DANCE:Lp(a)/apo(a) interaction remains speculative.

Atherosclerosis as an autoimmune disease: an update.

Immunoinflammatory processes are discussed increasingly as possible pathogenic factors for the development of atherosclerosis. Here, we summarize the data on which we have built our immunological hypothesis of atherogenesis. This concept is based on the observation that almost all humans have cellular and humoral immune reactions against microbial heat-shock protein 60 (HSP60). Because a high degree of antigenic homology exists between microbial (bacterial and parasitic) and human HSP60, the 'cost' of immunity to microbes might be the danger of cross-reactivity with human HSP60 expressed by the endothelial cells of stressed arteries. Genuine autoimmunity against altered autologous HSP60 might trigger this process also.

The vascular-associated lymphoid tissue: a new site of local immunity.

Recent data suggest that atherosclerosis might be a systemic (auto)immune reaction against heat shock protein 60, first occurring at notorious local predilection sites, i.e. the intima at arterial branching points. The local infiltration of mononuclear cells, mainly macrophage-derived foam cells, T cells and smooth-muscle cells in atheromatous plaques, have long been described. During the past few years, research has been concentrated on the early stages in the development of atherosclerosis, and on healthy arteries from young individuals unaffected by arterial disease. In this review, we summarize data characterizing pre-existing mononuclear cell infiltrations in healthy arteries from children and teenagers. These arterial accumulations at regions known to be predilection sites for the later development of atherosclerosis consist mostly of activated T cells, macrophages and dendritic cells, with only a few mast cells and virtually no B or natural killer cells. In analogy to the mucosa-associated lymphoid tissue, we termed these accumulations 'vascular-associated lymphoid tissue', and assumed a similar function as a local immunosurveillance system, monitoring the bloodstream for potentially harmful endogenous or exogenous antigens. In addition to the remarkable accumulation of mononuclear cells, the vascular-associated lymphoid tissue regions are characterized by a typical distribution of extracellular matrix proteins: collagen type I, collagen type III, fibronectin and tenascin are expressed preferentially in the vascular-associated lymphoid tissue region, whereas collagen type IV, collagen type V, collagen type VI and laminin show a homogenous distribution throughout all regions of the intima. Vascular adhesion molecules type 1, intercellular adhesion molecules type 1 and P-selectin are already present on the healthy endothelial cells of young children. Interactions between adhesion molecules, extracellular matrix components and cellular elements of the vascular-associated lymphoid tissue may provide the basis for the cellular accumulations in the vascular-associated lymphoid tissue regions and the possible development of atherosclerotic lesions later in life.

Network of vascular-associated dendritic cells in intima of healthy young individuals.

In earlier studies, our group has established a new "immunological" hypothesis for atherogenesis supported by experimental and clinical studies showing that inflammatory immunological reactions against heat shock protein 60 initiate the development of atherosclerosis. In the present study, we describe the discovery of a so-far-unknown network of dendritic cells in the innermost layer of arteries, the intima, but not veins of healthy humans and rabbits. The number of these dendritic cells is comparable to that of Langerhans cells in the skin, and dendritic cells show a similar phenotype (CD1a(+) S-100(+) lag(+) CD31(-) CD83(-) CD86(-) and no staining for von Willebrand factor or smooth muscle cell myosin). These vascular-associated dendritic cells accumulate most densely in those arterial regions that are subjected to major hemodynamic stress by turbulent flow conditions and are known to be predisposed for the later development of atherosclerosis. These results open new perspectives for the activation of the immune system within the arterial wall.

Ultrastructural study of gonads in the complete and incomplete feminization syndrome.

The gonads of two individuals with complete and one with incomplete testicular feminization were examined by light and electron microscopy. In the seminiferous tubules of the complete forms, clear, intermediate, and dark-type Sertoli cells could be distinguished. These are immature elements which had assumed, under the influence of hormones, different morphology. Leydig cells were also immature, at varying stages of differentiation. In the complete form Sertoli and Leydig cells had an almost normal fine structure; the lamina basalis of the tubules, however, was considerably thickened.