Background— Assessment of risk and appropriate management of patients with acute pulmonary embolism (PE) remains a challenge. Cardiac troponins I (cTnI) and T (cTnT) are reliable indicators of myocardial injury and may be associated with right ventricular dysfunction in PE. Methods and Results— The present prospective study included 106 consecutive patients with confirmed acute PE. cTnI was elevated (≥0.07 ng/mL) in 43 patients (41%), and cTnT (≥0.04 ng/mL) was elevated in 39 (37%). Elevation of cTnI or cTnT was significantly associated with echocardiographically detected right ventricular dysfunction ( P =0.001 and P <0.05, respectively). Moreover, a significant correlation was found between elevation of cTnI or cTnT and the two major end points overall mortality and complicated in-hospital course. The negative predictive value of cardiac troponins for major clinical events was 92% to 93%. Importantly, there was obvious escalation of in-hospital mortality, the rate of complications, and the incidence of recurrent PE, when patients with high troponin concentrations (cTnI >1.5; cTnT >0.1 ng/mL) were compared with those with only moderately elevated levels (cTnI, 0.07 to 1.5; cTnT, 0.04 to 0.1 ng/mL). Logistic regression analysis confirmed that the mortality risk (OR) was significantly elevated only in patients with high cTnI ( P =0.019) or cTnT ( P =0.038) levels. Furthermore, the risk of a complicated in-hospital course was almost 5 times higher (15.47 versus 3.16) in the high-cTnI group compared with patients with moderate cTnI elevation. Conclusions— Our results indicate that cTnI and cTnT may be a novel, particularly useful tool for optimizing the management strategy in patients with acute PE.

Annexins are a family of calcium-dependent phospholipid-binding proteins, which have been implicated in a variety of biological processes including membrane trafficking. The annexin 6/lgp120 prelysosomal compartment of NRK cells was loaded with low-density lipoprotein (LDL) and then its transport from this endocytic compartment and its degradation in lysosomes were studied. NRK cells were microinjected with the mutated annexin 6 (anx6(1-175)), to assess the possible involvement of annexin 6 in the transport of LDL from the prelysosomal compartment. The results indicated that microinjection of mutated annexin 6, in NRK cells, showed the accumulation of LDL in larger endocytic structures, denoting retention of LDL in the prelysosomal compartment. To confirm the involvement of annexin 6 in the trafficking and the degradation of LDL we used CHO cells transfected with mutated annexin 6(1-175). Thus, in agreement with NRK cells the results obtained in CHO cells demonstrated a significant inhibition of LDL degradation in CHO cells expressing the mutated form of annexin 6 compared to controls overexpressing wild-type annexin 6. Therefore, we conclude that annexin 6 is involved in the trafficking events leading to LDL degradation.

BACKGROUND AND STUDY AIMS:The results of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in focal pancreatic lesions are less impressive than those in the mediastinum. The aim of this prospectively randomized study was to compare two commercially available needle assemblies with regard to handling and cytopathological yield.PATIENTS AND METHODS:A total of 30 patients (19 men, 11 women; mean age 61) with focal pancreatic lesions underwent EUS-FNA with each of the two needles (GIP, Wilson-Cook). The sequence was randomized for the examiner and blinded for the cytologist. Three patients had to be excluded because of the impossibility of sample assignment or patient follow-up. EUS-FNA was performed using the standard technique with linear echo endoscopes.RESULTS:None of the characteristics evaluated by the examiner differed significantly between either of the needles. Inadequate results were obtained in 11% using the GIP needle, but in none with the Wilson-Cook needle. GIP needle cytology revealed malignancy in 11 patients (sensitivity, specificity, and accuracy were 55%, 100%, and 65%, respectively, including inadequate results). The aspirates obtained with the Wilson-Cook needle identified malignancy in 16 patients (sensitivity, specificity, and accuracy were 85%, 100%, and 89%, respectively).CONCLUSIONS:No statistically significant differences were detected in the handling of either of the two needle assemblies. No complications were reported using the GIP needles. However, in four procedures breakages of the outer Teflon sheath of the Wilson-Cook needle occurred, and in another four cases re-insertion of the stylet was impossible. Nevertheless, cytopathologic results were significantly better with the Wilson-Cook needle.

We have recently described a novel recycling pathway of triglyceride-rich lipoprotein (TRL)-associated apolipoprotein (apo) E in human hepatoma cells. We now demonstrate that not only TRL-derived apoE but also lipoprotein lipase (LPL) is efficiently recycled in vitro and in vivo. Similar recycling kinetics of apoE and LPL in normal and low density lipoprotein receptor-negative human fibroblasts also indicate that the low density lipoprotein receptor-related protein seems to be involved. Intracellular sorting mechanisms are responsible for reduced lysosomal degradation of both ligands after receptor-mediated internalization. Immediately after internalization in rat liver, TRLs are disintegrated, and apoE and LPL are found in endosomal compartments, whereas TRL-derived phospholipids accumulate in the perinuclear region of hepatocytes. Subsequently, substantial amounts of both proteins can be found in purified recycling endosomes, indicating a potential resecretion of these TRL components. Pulse-chase experiments of perfused rat livers with radiolabeled TRLs demonstrated a serum-induced release of internalized apoE and LPL into the perfusate. Analysis of the secreted proteins identified similar to 80% of the recycled TRL-derived proteins in the high density lipoprotein fractions. These results provide the first evidence that recycling of TRL-derived apoE and LPL could play an important role in the modulation of lipoproteins in vivo.

Annexin VI is an abundant calcium- and phospholipid-binding protein whose intracellular distribution and function are still controversial. Using a highly specific antibody, we have studied the distribution of annexin VI in NRK fibroblasts and the polarized hepatic cell line WIF-B by confocal microscopy. In NRK cells, annexin VI was almost exclusively found associated with endocytic compartments, which were defined by their ability to receive fluid-phase marker internalized from the cell surface. However, extensive colocalization of annexin VI and the endocytic marker was only observed after about 45 min, indicating that annexin VI was primarily in late endocytic compartments or (pre)lysosomes. Consistent with this, annexin VI was predominantly seen on structures that contained the lysosomal protein lgp120, although not on dense core lysosomes by electron microscopy. Two major populations of annexin VI-containing structures were present in polarized WIF-B hepatocytes. One correlated to lgp120-positive (pre)lysosomes and was still observed after treatment with brefeldin A (BFA), while the other appeared to be partially associated with Golgi membranes and was BFA-sensitive. The striking association with prelysosomal compartments in NRK and WIF-B cells suggests that annexin VI could play a role in fusion events in the late endocytic pathway, possibly by acting as a tether between membranes.

BACKGROUND AND STUDY AIMS:Optical coherence tomography (OCT) is a new technique for high-resolution cross-sectional imaging using infrared light. It has over 10 times the resolution of the currently available ultrasonography. Although in vitro studies have suggested its potential for gastrointestinal imaging, in vivo studies have not been possible so far on account of technical limitations.PATIENTS AND METHODS:We describe here the first clinical study of OCT during routine endoscopy obtaining high resolution images of the normal esophageal, gastric, and colonic mucosa. Portable OCT equipment and a fiberoptic-based flexible probe for endoscopic use have been developed by the authors.RESULTS:Differences in the optical properties of epithelium, lamina propria, muscularis mucosae, and submucosa enabled distinction of the mucosal architecture. Owing to the low penetration depth (1 mm) and high resolution (10 microm), OCT images may become comparable to mucosal histological findings. Image acquisition time was 1.5 seconds, and the entire procedure was completed within 5 minutes. Endoscopic OCT images of colonic adenoma and carcinoma were also studied and compared with the corresponding histology.CONCLUSIONS:The newly developed portable OCT equipment and flexible fiberoptic probe makes OCT a promising method for endoscopic "optical biopsy".

Annexins are calcium-binding proteins with a wide distribution in most polarized and nonpolarized cells that participate in a variety of membrane-membrane interactions. At the cell surface, annexin VI is thought to remodel the spectrin cytoskeleton to facilitate budding of coated pits. However, annexin VI is also found in late endocytic compartments in a number of cell types, indicating an additional important role at later stages of the endocytic pathway. Therefore overexpression of annexin VI in Chinese hamster ovary cells was used to investigate its possible role in endocytosis and intracellular trafficking of low density lipoprotein (LDL) and transferrin. While overexpression of annexin VI alone did not alter endocytosis and degradation of LDL, coexpression of annexin VI and LDL receptor resulted in an increase in LDL uptake with a concomitant increase of its degradation. Whereas annexin VI showed a wide intracellular distribution in resting Chinese hamster ovary cells, it was mainly found in the endocytic compartment and remained associated with LDL-containing vesicles even at later stages of the endocytic pathway. Thus, data presented in this study suggest that after stimulating endocytosis at the cell surface, annexin VI remains bound to endocytic vesicles to regulate entry of ligands into the prelysosomal compartment.

Background: Up to 10 % of patients with Barrett's esophagus develop adenocarcinoma of the distal esophagus. Endoscopic surveillance is recommended. We studied the potential of Argon plasma coagulation (APC) for eradication of Barrett's esophagus. Methods: Indication for APC was the histologic evidence of columnar epithelium with a length of greater than or equal to 2 cm, located proximal of the cardia and with the presence of goblet cells. Endoscopic therapy was performed using an Argonbeamer (Beamer 2, Erbe Company, Tubingen, Germany) under i.v. sedation and repeated in intervals of 2-3 weeks with the aim of complete eradication of Barrett's epithelium. One month after macroscopic Barrett eradication, superficial and deep biopsies were obtained every 2 cm in 4 quadrant technique to confirm the endoscopic aspect of complete eradication. Results: We report our results (follow-up median: 12 mths., 3-25) in the first 12 patients (8m/4f, median age 57 yrs., 42-69) in which treatment was completed. In one case there was evidence of moderate dysplasia. A mean of 5 (4-11) sessions were required for complete Barrett eradication in 11 patients (median size of Barrett-segment: 4 cm, range 2-11), in one patient partial regression of 50 % was observed treatment was discountinued after 17 sessions while only. Deep biopsies showed subepithelial columnar epithelium islands in one case, recurrence of Barrett occurred in 2 cases after 3 and 6 months. Under APC-treatment, 11/12 patients complained about retrosternal pain and odynophagia. No other complications were observed. Conclusion: Our preliminary results indicate that APC is safe and effective to eradicate Barrett's epithelium. Follow-up in a larger number of patients is necessary to assess longterm results (Barrett recurrence, decrease in the incidence of the adenocarcinoma), before APC may generally be recommended.

La ligature endoscopique de varices (LEV) s’est avérée être un traitement efficace des hémorragies par rupture de varices œsophagiennes avec un faible taux de complications. En cas d’hémorragie massive de varices œsophagiennes ou gastriques, l’injection de N-butyl(2)-cyanoacrylate est considérée comme le traitement le plus efficase aussi bien pour obtenir l’hémostase primaire que pour obtenir une réduction du taux de récidives.

Background: Endoscopic ultrasound is increasingly used for evaluation of pancreatic cancer. The potential of sonographic morphology to differentiate histology type and biological behaviour of pancreatic lesions is doubtful. Methods: We prospectively studied 115 patients with focal pancreatic lesions on endoscopic ultrasound. Morphology was assessed using Olympus UM3/20/200 echoendoscopes. Histologic confirmation of diagnosis was obtained in all patients. Results: Endoscopic ultrasound correctly diagnosed 18/34 benign and 77/81 malignant lesions. Sensitivity, specificity, accuracy, PPV and NPV for diagnosing malignancy were 95%, 53%, 83%, 83% and 82%, respectively. Endosonographic diagnosis of the lesions (% correct) were: pancreatic cancer, 84 (63.3%); chronic pancreatitis, 14 (71.4%); ampullary cancer, 9 (77.8%); cystadenoma, 5 (80%); ampullary adenoma, 2 (50%); acute pancreatitis, 1 (0). In 13 patients of chronic pancreatitis, diagnosed as cancer, diagnosis was based on absence of sonographic features of chronic pancreatitis (7) or suspected involvement of adjacent structures (6). In 3 patients malignancy was missed owing to features of chronic pancreatitis. Non-suspected neuroendocrine tumours were misjudged in all 10 cases using morphologic criteria as pancreatic cancer (8), cystadenoma and chronic pancreatitis. Accuracy for prediction of metastatic lymph nodes and an advanced pancreatic cancer stage (TxN1 or T3Nx) was 61% and 75%, respectively. On retrospective analysis, a lesion >2 cm, vessel ingrowth, absence of cystic spaces and absence of diffuse pancreatitis were associated with pancreatic cancer. Conclusions: While overall sensitivity was high, specificity of endoscopic ultrasound for diagnosis of malignancy was low, especially in presence of chronic pancreatitis. In addition, endosonography had only a limited potential to predict the histological type of lesions.

Endosonography and endosonography-guided fine-needle aspiration (EUS-FNA) are now established diagnostic techniques, which are performed electively in endoscopy suites. We report here the bedside use of EUS-FNA in three critically ill patients in an intensive-care unit, with a significant impact on the outcome. A mediastinal abscess after percutaneous dilational tracheotomy was aspirated in one patient, leading to appropriate antibiotic therapy and complete recovery. A paratracheal hematoma compressing the right main bronchus was aspirated in a patient with polytrauma, relieving the pressure effects. The third patient, who had end-stage dilated cardiomyopathy and was being evaluated for cardiac transplantation, was found to have an apical lung lesion suspicious for bronchogenic carcinoma. EUS was performed to exclude mediastinal metastasis and allow simultaneous resection at the time of transplantation. Although a metastasis was excluded by EUS-FNA, the patient died while awaiting surgery. We conclude that bedside EUS-FNA is a feasible procedure, and in experienced hands it can offer an alternative in life-threatening situations.

BACKGROUND Up to 10% of patients with Barrett's esophagus develop adenocarcinoma of the distal esophagus. Endoscopic surveillance is recommended. We studied the potential of Argon plasma coagulation (APC) for eradication of Barrett's esophagus. METHODS Indication for APC was the histologic evidence of columnar epithelium with a length of > or = 2 cm, located proximal of the cardia and with the presence of goblet cells. Endoscopic therapy was performed using an Argonbeamer (Beamer 2, Erbe Company, Tübingen, Germany) under i.v. sedation and repeated in intervals of 2-3 weeks with the aim of complete eradication of Barrett's epithelium. One month after macroscopic Barrett eradication, superficial and deep biopsies were obtained every 2 cm in 4 quadrant technique to confirm the endoscopic aspect of complete eradication. RESULTS We report our results (follow-up median: 12 mths., 3-25) in the first 12 patients (8m/4f, median age 57 yrs., 42-69) in which treatment was completed. In one case there was evidence of moderate dysplasia. A mean of 5 (4-11) sessions were required for complete Barrett eradication in 11 patients (median size of Barrett-segment: 4 cm, range 2-11), in one patient partial regression of 50% was observed treatment was discontinued after 17 sessions while only. Deep biopsies showed subepithelial columnar epithelium islands in one case, recurrence of Barrett occurred in 2 cases after 3 and 6 months. Under APC-treatment, 11/12 patients complained about retrosternal pain and odynophagia. No other complications were observed. CONCLUSION Our preliminary results indicate that APC is safe and effective to eradicate Barrett's epithelium. Follow-up in a larger number of patients is necessary to assess longterm results (Barrett recurrence, decrease in the incidence of the adenocarcinoma), before APC may generally be recommended.

Background and Study Aims: Dilation of high grade strictures of pancreatic or biliary ducts using dilating or balloon catheters may fail. We evaluated the efficacy of the 7-Fr Soehendra Stent Retriever used as a dilator.Patients ann Methods: Following sphincterotomy, the stricture was first negotiated with a 260 cm long 0.032-inch J-type Terumo wire. Dilation was then attempted using a 7-Fr dilating catheter, If the stricture could not be traversed, the 7-Fr Stent Retriever aas inserted over the Terumo wire to dilate the stricture. Between May 1996 and January 1997, the Stent Retriever was used for dilation in 32 patients with biliary or pancreatic duet strictures.Results: The indication for therapeutic endoscopic retrograde cholangiopancreatography, (ERCP) was symptomatic chronic pancreatitis in 21 patients (twelve men, nine women; mean age 45.7, range 26-70), The mean length (+/- SD) of the pancreatic duct strictures was 20 mm +/- 10 (range 3-55) with a prestenotic ductal diameter of 9 mm +/- 2 (range 2-15), Out of 21 patients, nine suffered from pancreaticolithiasis and were treated with extracorporeal shock wave lithotripsy. All but three patients underwent successful stenting in the same session. Another 11 patients (four men, seven women; mean age 67.4, range 47-85) had cholestasis because of benign or malignant bile duct strictures. The mean length of the strictures was 20 mm +/- 5 (range 3-40), and the mean prestenotic diameter was 10 mm +/- 5 (range 4-21), Stenting was easily done in ail of these patients in the same session. Symptom relief was observed within the first week after stenting in all patients with a biliary or pancreatic stricture. In seven cases, material for cytological examination was obtained from the bile duct, which revealed malignancy in two cases. There was no complication associated with the use of the Stent Retriever. One subcapsular liver perforation was caused by the guide wire and occurred prior to the use of the Retriever.Conclusions: Tight pancreatic and bile duct strictures can be dilated successfully with the Stent Retriever. The procedure is of low risk, In addition, tissue sampling is possible in some eases.

The endocytic compartment is a complex intracellular heterogeneous organelle, which consists of an extensive network of tubulo-vesicular membranes extending from the cell surface to the perinuclear area. It is involved in the uptake, sorting, and processing of nutrients, metabolites, hormones, and growth factors; the maintenance of the characteristic distribution of the plasma membrane functional domains in polarized epithelial cells; and the recycling of receptors and ligands. Although the boundaries of the endocytic compartment are not completely defined, several probes, marker proteins, subcellular fractionation, and accurate morphological information have topologically delimited and characterized the ‘‘early/sorting’’ as well as the multivesicular ‘‘late’’ endosomes. However, the ‘‘recycling endosomes,’’ characterized by the enrichment in recycling receptors and depletion of ligands that are routed to lysosomes for degradation, lack a clear-cut definition and intracellular location. Recently, using isolated endosomes, progress has been made towards the biochemical and functional dissection of the endocytic compartment of the rat liver. The compartment of recycling emerges as a very complex fraction containing structures involved in recycling, transcytosis, and the caveolin cycle. The aim of this review is to emphasize the complexity of the ‘‘receptor-recycling’’ endocytic compartment in the hepatic trafficking pathways and put together the latest molecular data, which suggest that structures contained in this compartment might be also committed to shuttling the signal transduction machinery from the cell surface to the sorting endosomes. The hepatic cell is a useful experimental epithelial-tissue model for studying the endocytic pathways for 2 reasons: first, hepatocytes are highly active metabolically and contain